KR102681639B1 - Display device - Google Patents

Abstract

A display device according to an example of the present application includes a substrate having a first sub-pixel and a second sub-pixel adjacent to the first sub-pixel, a first sub-electrode provided on the substrate and provided in the first sub-pixel, and a second sub-pixel. A first electrode including a second sub-electrode provided in a sub-pixel, an organic light-emitting layer including a first organic light-emitting layer disposed on the first sub-electrode, and a second organic light-emitting layer disposed on the second sub-electrode, on the organic light-emitting layer It includes a second electrode disposed in and a first bank provided between the first sub-electrode and the second sub-electrode to distinguish the first sub-pixel and the second sub-pixel, and the first organic light-emitting layer is on the light-emitting layer and the light-emitting layer. It includes a first hole transport layer disposed, wherein the first hole transport layer includes a first sub hole transport layer and a second sub hole transport layer, and the first sub hole transport layer of the first hole transport layer is between the light emitting layer and the second sub hole transport layer. By being provided to cover the light-emitting layer, it is possible to prevent the organic light-emitting layer from being damaged by an exposure process or a solution process, thereby reducing the defect rate of the finished display device.

Description

Display device {DISPLAY DEVICE}

This application relates to a display device that displays images.

As the information society develops, the demand for display devices for displaying images is increasing in various forms. Accordingly, recently, various display devices such as liquid crystal display devices, light emitting display devices, organic light emitting display devices, micro light emitting display devices, quantum dot light emitting display devices, etc. have been used.

Organic light emitting display devices can produce small and medium-sized panels due to mask shadows due to the problem of sagging of the deposition mask when using FMM technology when forming red, green, and blue pixels of the organic light emitting layer, but application to large areas is difficult. In addition, even when producing a panel using FMM, there is a limit to reducing the size of each pixel, making it difficult to apply ultra-high resolution.

The technical task of this application is to provide a display device that can prevent the device characteristics of the organic light-emitting layer from being deteriorated.

A display device according to an embodiment of the present application includes a substrate having a first sub-pixel and a second sub-pixel adjacent to the first sub-pixel, a first sub-electrode provided on the substrate and provided in the first sub-pixel, and a second sub-pixel. A first electrode including a second sub-electrode provided in 2 sub-pixels, an organic light-emitting layer including a first organic light-emitting layer disposed on the first sub-electrode and a second organic light-emitting layer disposed on the second sub-electrode, an organic light-emitting layer It includes a second electrode disposed on the first sub-electrode and a first bank provided between the first sub-electrode and the second sub-electrode to distinguish the first sub-pixel and the second sub-pixel, and the first organic emission layer is formed on the emission layer and the emission layer. It includes a first hole transport layer disposed in, wherein the first hole transport layer includes a first sub hole transport layer and a second sub hole transport layer, and the first sub hole transport layer of the first hole transport layer is between the light emitting layer and the second sub hole transport layer. It may be provided to cover the light emitting layer.

The display device according to the present application includes a first sub hole transport layer to cover the light emitting layer of the organic light emitting layer, thereby preventing the organic light emitting layer from being damaged by the exposure process or solution process, thereby reducing the defect rate of the finished display device. .

In addition to the effects of the present application mentioned above, other features and advantages of the present application are described below, or can be clearly understood by those skilled in the art from such description and description.

1 is a schematic cross-sectional view of a display device according to a first embodiment of the present application.
2A to 2P are schematic cross-sectional views of the manufacturing process of the display device according to the first embodiment of the present application.
Figure 3 is a schematic structural diagram of part A of Figure 1.
FIG. 4 is a graph showing the ratio of oxygen contained in the first sub hole transport layer and the second sub hole transport layer of FIG. 3.
Figure 5 is a schematic structural diagram of part B of Figure 3.
Figure 6 is a graph showing the voltage change according to driving of the organic light emitting layer of the display device according to the first embodiment of the present application.
Figure 7 is a graph showing improvement in the lifespan of the organic light emitting layer of the display device according to the first embodiment of the present application.
Figure 8 is a schematic cross-sectional view of a display device according to a second embodiment of the present application.
Figure 9 is a schematic cross-sectional view of a display device according to a third embodiment of the present application.
10A to 10J are schematic cross-sectional views of the manufacturing process of the display device according to the third embodiment of the present application.
Figure 11 is a schematic cross-sectional view of a display device according to a fourth embodiment of the present application.
12A to 12P are schematic cross-sectional views of the manufacturing process of a display device according to a fourth embodiment of the present application.
Figure 13 is a graph showing improvement in the lifespan of the organic light emitting layer of the display device according to the fourth embodiment of the present application.
Figure 14 is a schematic cross-sectional view of a display device according to a fifth embodiment of the present application.
15A to 15P are schematic cross-sectional views of the manufacturing process of the display device according to the fifth embodiment of the present application.
16A to 16C relate to a display device according to a sixth embodiment of the present application, which relates to a head mounted display (HMD) device.

The advantages and features of the present application and methods for achieving them will become clear by referring to the examples described in detail below along with the accompanying drawings. However, the present application is not limited to the examples disclosed below and will be implemented in various different forms. These examples only serve to ensure that the disclosure of the present application is complete and to those skilled in the art to which the present application pertains. It is provided to fully inform the scope of the invention, and the present application is defined only by the scope of the claims.

The shape, size, ratio, angle, number, etc. disclosed in the drawings for explaining examples of the present application are illustrative, and the present application is not limited to the matters shown. Like reference numerals refer to like elements throughout the specification. Additionally, in describing the present application, if it is determined that a detailed description of related known technology may unnecessarily obscure the gist of the present application, the detailed description will be omitted. When 'comprises', 'has', 'consists of', etc. mentioned in the present application are used, other parts may be added unless 'only' is used. In cases where a component is expressed in the singular, the plural is included unless specifically stated otherwise.

When interpreting a component, it is interpreted to include the margin of error even if there is no separate explicit description.

In the case of a description of a positional relationship, for example, if the positional relationship of two parts is described as 'on top', 'on the top', 'on the bottom', 'next to', etc., 'immediately' Alternatively, there may be one or more other parts placed between the two parts, unless 'directly' is used.

Although first, second, etc. are used to describe various components, these components are not limited by these terms. These terms are merely used to distinguish one component from another. Accordingly, the first component mentioned below may also be the second component within the technical spirit of the present application.

In describing the components of this application, terms such as first, second, etc. may be used. These terms are only used to distinguish the component from other components, and the nature, sequence, order, or number of the components are not limited by the term. When a component is described as being “connected,” “coupled,” or “connected” to another component, that component may be directly connected or connected to that other component, but there are no other components between each component. It should be understood that may be “interposed” or that each component may be “connected,” “combined,” or “connected” through other components.

Each feature of the various examples of the present application can be partially or entirely combined or combined with each other, and various technological interconnections and operations are possible, and each example may be implemented independently of each other or together in a related relationship. .

Hereinafter, an example of a display device according to the present application will be described in detail with reference to the attached drawings. In adding reference numerals to components in each drawing, identical components may have the same reference numerals as much as possible even if they are shown in different drawings.

FIG. 1 is a schematic cross-sectional view of a display device according to a first embodiment of the present application, and FIGS. 2A to 2P are schematic cross-sectional views of a manufacturing process of a display device according to a first embodiment of the present application.

1 to 2P, the display device 1 according to the first embodiment of the present application includes a substrate 2, a circuit element layer 3, a first electrode 4, a first bank 5, It includes an organic light-emitting layer (6), a second electrode (7), an encapsulation layer (8), and a second bank (9). The organic light-emitting layer 6 includes a light-emitting layer and a first hole transport layer, the first hole transport layer includes a first sub-hole transport layer and a second sub-hole transport layer, and the first sub-hole transport layer includes the light-emitting layer and the second hole transport layer. It is disposed between the two sub hole transport layers to cover the light emitting layer.

The substrate 2 may be a plastic film, a glass substrate, or a semiconductor substrate such as silicon. The substrate 2 may be made of a transparent material or an opaque material.

A first sub-pixel 21, a second sub-pixel 22, and a third sub-pixel 23 are provided on the substrate 2. The second sub-pixel 22 according to one example may be disposed adjacent to one side of the first sub-pixel 21. The third sub-pixel 23 according to one example may be disposed adjacent to one side of the second sub-pixel 22. Accordingly, the first sub-pixel 21, the second sub-pixel 22, and the third sub-pixel 23 may be sequentially arranged on the substrate 2.

The first sub-pixel 21 emits red (R) light, the second sub-pixel 22 emits green (G) light, and the third sub-pixel 23 emits blue (B) light. It may be equipped to emit light, but is not necessarily limited thereto, and may emit light of various colors including white. Additionally, the arrangement order of each sub-pixel 21, 22, and 23 may be changed in various ways.

Each of the first sub-pixel 21, the second sub-pixel 22, and the third sub-pixel 23 includes a first electrode 4, an organic light-emitting layer 6, and a second electrode 7. It may be provided to do so. Here, the first electrode 4 may be a cathode electrode. And, the second electrode 7 may be an anode electrode. Accordingly, the display device 1 according to the first embodiment of the present application may be provided in a structure in which the cathode electrode is disposed at the bottom and the anode electrode is disposed at the top. The first electrode 4 may include a first sub-electrode 41, a second sub-electrode 42, and a third sub-electrode 43.

The display device 1 according to the first embodiment of the present application is made of a so-called top emission method in which the emitted light is emitted toward the top, and therefore, the material of the substrate 2 includes not only a transparent material but also a transparent material. Opaque materials may be used.

The circuit element layer 3 is provided on one side of the substrate 2.

The circuit element layer 3 is provided with circuit elements including a plurality of thin film transistors 31, 32, and 33, various signal wires, and capacitors for each sub-pixel 21, 22, and 23. The signal wires may include a gate line, a data line, a power line, and a reference line, and the thin film transistors 31, 32, and 33 may include a switching thin film transistor, a driving thin film transistor, and a sensing thin film transistor. there is. The sub-pixels 21, 22, and 23 are defined by an intersection structure of gate lines and data lines.

The switching thin film transistor switches according to a gate signal supplied to the gate line and serves to supply the data voltage supplied from the data line to the driving thin film transistor.

The driving thin film transistor switches according to the data voltage supplied from the switching thin film transistor to generate a data current from the power supplied from the power line and supplies it to the first electrode 4.

The sensing thin film transistor serves to sense the threshold voltage deviation of the driving thin film transistor, which causes deterioration of image quality, and controls the current of the driving thin film transistor in response to a sensing control signal supplied from the gate line or a separate sensing line. is supplied to the reference line.

The capacitor serves to maintain the data voltage supplied to the driving thin film transistor for one frame, and is connected to the gate terminal and source terminal of the driving thin film transistor, respectively.

The first transistor 31, the second transistor 32, and the third transistor 33 are arranged for each individual sub-pixel 21, 22, and 23 within the circuit element layer 3. The first transistor 31 according to an example is connected to the first sub-electrode 41 disposed on the first sub-pixel 21 and driven to emit light of the color corresponding to the first sub-pixel 21. Voltage can be applied.

The second transistor 32 according to an example is connected to the second sub-electrode 42 disposed on the second sub-pixel 22 and driven to emit light of the color corresponding to the second sub-pixel 22. Voltage can be applied.

The third transistor 33 according to an example is connected to the third sub-electrode 43 disposed on the third sub-pixel 23 and driven to emit light of the color corresponding to the third sub-pixel 23. Voltage can be applied.

According to one example, each of the first sub-pixel 21, the second sub-pixel 22, and the third sub-pixel 23 receives a gate signal from a gate line using respective transistors 31, 32, and 33. If possible, a predetermined current is supplied to the organic light emitting layer according to the data voltage of the data line. Due to this, the organic light emitting layer of each of the first sub-pixel 21, the second sub-pixel 22, and the third sub-pixel 23 can emit light with a predetermined brightness according to a predetermined current.

The first electrode 4 is formed on the circuit element layer 3. The first electrode 4 according to one example includes aluminum, a stacked structure of aluminum and titanium (Ti/Al/Ti), a stacked structure of aluminum and ITO (ITO/Al/ITO), an APC alloy, and a stacked structure of APC alloy and ITO. It can be formed by including a highly reflective metal material such as a laminated structure (ITO/APC/ITO). APC alloy is an alloy of silver (Ag), palladium (Pb), and copper (Cu). The first electrode 4 may be a cathode. The first electrode 4 may include a first sub-electrode 41, a second sub-electrode 42, and a third sub-electrode 43.

The first sub-electrode 41 may be provided in the first sub-pixel 21. The first sub-electrode 41 may be formed on the circuit element layer 3. The first sub-electrode 41 is connected to the source electrode of the first transistor 31 through a contact hole penetrating the circuit element layer 3.

The second sub-electrode 42 may be provided in the second sub-pixel 22. The second sub-electrode 42 may be formed on the circuit element layer 3. The second sub-electrode 42 is connected to the source electrode of the second transistor 32 through a contact hole penetrating the circuit element layer 3.

The third sub-electrode 43 may be provided in the third sub-pixel 23. The third sub-electrode 43 may be formed on the circuit element layer 3. The third sub-electrode 43 is connected to the source electrode of the third transistor 33 through a contact hole penetrating the circuit element layer 3.

Here, the first to third transistors 31, 32, and 33 may be N-type TFTs.

If the first to third transistors 31, 32, and 33 are provided as P-type TFTs, each of the first to third sub-electrodes 41, 42, and 43 is the first to third transistors 31, 32, and 33. The transistors 31, 32, and 33 may be connected to their respective drain electrodes.

That is, each of the first to third sub-electrodes 41, 42, and 43 may be connected to a source electrode or a drain electrode depending on the type of the first to third transistors 31, 32, and 33.

The display device 1 according to the first embodiment of the present application is made of a top emission type, and therefore, the first to third sub-electrodes 41, 42, and 43 emit light emitted from the organic light emitting layer 6. It may include a reflective material to reflect upward. In this case, the first to third sub-electrodes 41, 42, and 43 may have a stacked structure of a transparent electrode made of a transparent conductive material and a reflective electrode made of the reflective material. Although not shown, a separate transparent electrode is additionally provided below the reflective electrode, so that each of the first to third sub-electrodes 41, 42, and 43 is a separate transparent electrode, a reflective electrode, and a transparent electrode in that order. It may be composed of a stacked three-layer structure.

At this time, the reflective electrode provided in the first sub-pixel 21, the reflective electrode provided in the second sub-pixel 22, and the reflective electrode provided in the third sub-pixel 23 are all made of the same material. It can be formed to have the same thickness.

Likewise, the transparent electrode provided in the first sub-pixel 21, the transparent electrode provided in the second sub-pixel 22, and the transparent electrode provided in the third sub-pixel 23 are all made of the same material. It can be formed to have a thickness. However, it is not necessarily limited to this, and the thickness of the transparent electrodes provided in each sub-pixel (21, 22, 23) is used to adjust the separation distance of each sub-electrode (41, 42, 43) with respect to the second electrode (7). may be different from each other. For example, when a display device is implemented using microcavity characteristics, the thickness of the transparent electrodes may be different. The micro cavity characteristic is such that the distance between the reflective electrode of the first electrode 4 and the second electrode 7 is equal to the half wavelength (λ/2) of the light emitted from each sub-pixel 21, 22, and 23. When the number is an integer multiple, constructive interference occurs and the light is amplified. When the above reflection and re-reflection process is repeated, the degree of light amplification continues to increase, which is a characteristic that improves the external extraction efficiency of light. When the display device is implemented to have micro cavity characteristics, the second electrode 7 may include a translucent electrode.

In order to implement the micro cavity characteristics as described above, the display device 1 according to the first embodiment of the present application adjusts the thickness of the first sub hole transport layer of the organic light emitting layer to the first to third sub pixels 21, 22, 23) By providing different electrodes, the distance between the first electrode 4 and the second electrode 7 can be adjusted differently. A detailed description of this will be provided in the display device 1 according to the second embodiment of the present application, which will be described later.

Referring again to FIG. 1, the first bank 5 is provided between the first sub-electrode 41 and the second sub-electrode 42. The first bank 5 according to one example is used to distinguish the first sub-pixel 21 and the second sub-pixel 22. The first bank 5 is provided to cover the edges of each of the first sub-electrode 41 and the second sub-electrode 42, thereby distinguishing the first sub-pixel 21 and the second sub-pixel 22. You can. The first bank 5 serves to define a sub-pixel, that is, a light emitting unit. Additionally, the area where the first bank 5 is formed does not emit light and can therefore be defined as a non-emission area. The first bank 5 may be formed of an organic film such as acryl resin, epoxy resin, phenolic resin, polyamise resin, or polyimide resin. You can. An organic light-emitting layer 6 is formed on the first electrode 4 and the first bank 5.

Referring to FIG. 1, the first bank 5 may include an upper surface 51 and an inclined surface 52. The inclined surface 52 may include a first inclined surface 521 and a second inclined surface 522.

The upper surface 51 of the first bank 5 is a surface located on the upper side of the first bank 5.

The first inclined surface 521 of the first bank 5 is a surface extending from the upper surface 51 to the upper surface 41a of the first sub-electrode 41. Accordingly, the first inclined surface 521 and the upper surface 41a of the first sub-electrode 41 may form a predetermined angle. The predetermined angle may be greater than 50° and less than 90° as the width of the bank narrows as display devices are implemented with high resolution. The width of the bank may narrow as the spacing between sub-pixels narrows.

The second inclined surface 522 of the first bank 5 is a surface extending from the upper surface 51 to the upper surface 42a of the second sub-electrode 42. Accordingly, the second inclined surface 522 and the upper surface 42a of the second sub-electrode 42 may form a predetermined angle. The angle formed by the second inclined surface 522 and the upper surface 42a of the second sub-electrode 42 is the angle formed by the first inclined surface 521 and the upper surface 41a of the first sub-electrode 41 and may be the same.

Referring to FIG. 1, the display device 1 according to the first embodiment of the present application may further include a second bank 9.

The second bank 9 is provided between the second sub-electrode 42 and the third sub-electrode 43. The second bank 9 according to an example is provided to cover the edges of each of the second sub-electrode 42 and the third sub-electrode 43, so that the second sub-pixel 22 and the third sub-pixel 23 can be distinguished. The second bank 9 serves to define a sub-pixel, that is, a light emitting unit. Additionally, the area where the second bank 9 is formed does not emit light and can therefore be defined as a non-emission area. The second bank 9 may be formed of the same material as the first bank 5. An organic light-emitting layer 6 is formed on the first electrode 4 and the second bank 9.

Referring to FIG. 1, the second bank 9 may include an upper surface 91 and an inclined surface 92. The inclined surface 92 may include a first inclined surface 921 and a second inclined surface 922.

The upper surface 91 of the second bank 9 is a surface located on the upper side of the second bank 9.

The first inclined surface 921 of the second bank 9 is a surface extending from the upper surface 91 to the upper surface 42a of the second sub-electrode 42. Accordingly, the first inclined surface 921 and the upper surface 42a of the second sub-electrode 42 may form a predetermined angle. The predetermined angle may be greater than 50° and less than 90° as the width of the bank narrows as display devices are implemented with high resolution.

The second inclined surface 922 of the second bank 9 is a surface extending from the upper surface 91 to the upper surface 43a of the third sub-electrode 43. Accordingly, the second inclined surface 922 and the upper surface 43a of the third sub-electrode 43 may form a predetermined angle. The angle formed by the second inclined surface 922 and the upper surface 43a of the third sub-electrode 43 is the angle formed by the first inclined surface 921 and the upper surface 42a of the second sub-electrode 42 and may be the same.

The organic light-emitting layer 6 is disposed on the first electrode 4. The organic light-emitting layer 6 according to one example includes an electron injection layer (EIL), an electron transporting layer (ETL), a light emitting layer (EML), a hole transporting layer (HTL), And it may include a hole injection layer (HIL). The hole transport layer (HTL) includes a first sub hole transport layer disposed on the upper surface of the light emitting layer (EML) and a second sub hole transport layer disposed on the upper surface of the first sub hole transport layer, and the first sub hole transport layer. It may be provided as a second hole transport layer disposed on the upper surface of the hole transport layer. The electron injection layer (EIL) may include both a layer composed of an EIL material and a layer doped in ETL and having electron injection characteristics. The layer doped in the ETL and having electron injection characteristics may be an N-doped electron transport layer. The N-doped electron transport layer is an electron transport layer plated with a metal material such as lithium, cesium, magnesium, etc. The N-doped electron transport layer may function as an electron injection layer (EIL). Accordingly, the display device 1 according to the first embodiment of the present application may be provided with an N-doped electron transport layer instead of the electron injection layer (EIL).

The hole injection layer (HIL), hole transport layer (HTL), electron transport layer (ETL), and electron injection layer (EIL) of the organic light emitting layer 6 are for improving the luminous efficiency of the light emitting layer (EML), and the hole transport layer ( The HTL) and electron transport layer (ETL) are for balancing electrons and holes, and the hole injection layer (HIL) and electron injection layer (EIL) are for strengthening the injection of electrons and holes.

More specifically, the hole injection layer (HIL) can facilitate hole injection by lowering the injection energy barrier of holes injected from the anode material, that is, the second electrode 7. The hole transport layer (HTL) serves to transport holes injected from the anode to the light emitting layer without loss.

The light emitting layer (EML) is a layer that emits light through the recombination of holes injected from the anode and electrons injected from the cathode. It can emit red, blue, and green light depending on the binding energy in the light emitting layer, and is composed of a plurality of light emitting layers. It is also possible to form a white light-emitting layer. The electron injection layer (EIL) serves to facilitate injection of electrons from the cathode, that is, the first electrode 4, by lowering the potential barrier during electron injection. The electron transport layer (ETL) serves to transport electrons injected from the electron injection layer (EIL) to the light emitting layer (EML).

When a high-potential voltage is applied to the first electrode 4 and a low-potential voltage is applied to the second electrode 7, holes and electrons move to the light-emitting layer through the hole transport layer and electron transport layer, respectively, and combine with each other in the light-emitting layer to emit light. do. Here, since the first electrode 4 is a cathode electrode, a negative voltage can be applied.

The organic emission layer 6 may include a first organic emission layer 61, a second organic emission layer 62, and a third organic emission layer 63.

The first organic light-emitting layer 61 may be disposed on the first sub-electrode 41. The first organic light emitting layer 61 may be formed on the first sub-electrode 41 after the first electrode 4, the first bank 5, and the second bank 9 are formed.

As shown in FIG. 1, the first organic light-emitting layer 61 includes an electron injection layer 611, an electron transport layer 612, a light-emitting layer 613, a first sub-hole transport layer 6141, and a second sub-hole transport layer ( It may be provided including a first hole transport layer 614, a second hole transport layer 615, and a hole injection layer 616 including 6142). A first hole transport layer 614 including the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, the first sub hole transport layer 6141, and the second sub hole transport layer 6142, The second hole transport layer 615 and the hole injection layer 616 may be formed sequentially in the first sub-pixel 21.

Here, in the display device 1 according to the first embodiment of the present application, the first sub hole transport layer 6141 of the first hole transport layer 614 of the first organic light emitting layer 61 is connected to the light emitting layer 613 and the second hole transport layer 6141. It may be provided to cover the light emitting layer 613 between the sub hole transport layers 6142.

Since the patterning process is performed so that the first sub hole transport layer 6141 and the light emitting layer 613 are disposed only in the first sub pixel 21 while the first sub hole transport layer 6141 covers the light emitting layer 613, The first sub hole transport layer 6141 can prevent the light emitting layer 613 from being damaged by UV light used in the exposure process of the patterning process, etching gas used in the dry etching process, and stripper solution used in the strip process. there is.

The display device 1 according to the first embodiment of the present application has a first sub-hole transport layer between the light-emitting layer 613 and the second sub-hole transport layer 6142 or between the light-emitting layer 613 and the second hole transport layer 615. A layer other than the sub hole transport layer 6141 may be disposed, but in this case, the energy level difference increases compared to the case where the first sub hole transport layer 6141 is disposed, so the luminous efficiency of the light emitting layer 613 may be lowered. .

Meanwhile, in the display device 1 according to the first embodiment of the present application, the second sub hole transport layer 6142, the second hole transport layer 615, and the hole injection layer 616 of the first organic light emitting layer 61 ) may be deposited on the entire surface of the first sub-pixel 21 as well as the second sub-pixel 22 and the third sub-pixel 23. That is, the second sub hole transport layer 6142, the second hole transport layer 615, and the hole injection layer 616 of the first organic light emitting layer 61 are the second sub hole transport layers of the second organic light emitting layer 62. , the second hole transport layer, and the hole injection layer are each connected to each other, and the second sub hole transport layer, the second hole transport layer, and the hole injection layer of the second organic light-emitting layer 62 are the same as the second hole transport layer of the third organic light-emitting layer 63. 2 It may be connected to each of the sub hole transport layer, the second hole transport layer, and the hole injection layer.

Accordingly, the second sub hole transport layer 6142, the second hole transport layer 615, and the hole injection layer 616 of the first organic light emitting layer 61 are of the second organic light emitting layer 62, as shown in FIG. It may be a second sub hole transport layer, a second hole transport layer, and a hole injection layer, and may be a second sub hole transport layer, a second hole transport layer, and a hole injection layer of the third organic light emitting layer 63. As a result, the second sub hole transport layer 6142, the second hole transport layer 615, and the hole injection layer 616 of the first organic light emitting layer 61 are the display device 1 according to the first embodiment of the present application. It can be placed on a common floor.

The second sub-hole transport layer 6142, the second hole transport layer 615, and the hole injection layer 616 of the first organic light-emitting layer 61 are disposed as a common layer, thereby forming the first sub-pixel 21 and the second sub-pixel 21. Not only can it cover the upper surface 51 and the inclined surface 52 of the first bank 5 disposed between the sub-pixels 22, but also can be disposed between the second sub-pixel 22 and the third sub-pixel 23. The upper surface 91 and the inclined surface 92 of the second bank 9 can be covered.

As a result, the display device 1 according to the first embodiment of the present application has a second sub hole transport layer, a second hole transport layer, and a hole injection layer of the first to third organic light emitting layers 61, 62, and 63, respectively. It can be provided to reduce the number of manufacturing processes compared to the case of patterning each of the first to third sub-pixels 21, 22, and 23.

Meanwhile, both ends of the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, and the first sub hole transport layer 6141 disposed in the first sub pixel 21 may be provided to coincide with each other. .

More specifically, the light-emitting layer 613 of the first organic light-emitting layer 61 is formed by depositing the entire surface of the electron injection layer 611 and the electron transport layer 612 of the first organic light-emitting layer 61 as a common layer, and then forming the first to the first organic light-emitting layer 61. It can be entirely deposited over three sub-pixels (21, 22, and 23). Next, the first sub hole transport layer 6141 is entirely deposited on the upper surface of the light emitting layer 613 of the first organic light emitting layer 61, and then the electron injection layer 611 and the electron transport layer 612 of the first organic light emitting layer 61. ), the light emitting layer 613, and the first sub hole transport layer 6141 may be patterned to be disposed only in the first sub pixel 21.

In this way, the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, and the first sub-hole transport layer 6141 of the first organic light-emitting layer 61 are patterned simultaneously, so that the first organic light-emitting layer ( Both ends of the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, and the first sub hole transport layer 6141 of 61) may be implemented to match each other as shown in FIG. 1. Therefore, the display device 1 according to the first embodiment of the present application includes the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, and the first sub hole transport layer ( 6141) at the same time, not only can the number of manufacturing processes be reduced compared to the case of patterning the electron injection layer, electron transport layer, light emitting layer, and first sub hole transport layer separately, but also the exposure, exposure, and It can be provided to prevent the overall luminous efficiency of the first organic light-emitting layer 61 from being reduced by reducing the degree of exposure to etching gas and strip solution.

Next, the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, and the first sub hole transport layer 6141 of the first organic light-emitting layer 61 patterned on the first sub-pixel 21 are covered. As shown, the second sub hole transport layer 6142, the second hole transport layer 615, and the hole injection layer 616 of the first organic light emitting layer 61 may be sequentially deposited as a common layer. Therefore, the second sub hole transport layer 6142 of the first organic light-emitting layer 61 is formed on the top and both sides of the first sub hole transport layer 6141, both sides of the light-emitting layer 613, and both sides of the electron transport layer 612. , and both sides of the electron injection layer 611 may be covered.

Here, the second sub hole transport layer 6142 of the first organic light emitting layer 61 is made of the same material as the first sub hole transport layer 6141 disposed on the uppermost side among the layers in which the patterning process was performed, thereby performing the patterning process. It is possible to compensate for the loss of the first sub hole transport layer 6141. Here, the meaning of compensating may mean forming a second sub hole transport layer 6142 equal to the thickness of the first sub hole transport layer 6141 lost by the patterning process, and the second sub hole transport layer 6142 whose energy level has been changed by the patterning process may be formed. This may mean reducing the energy level difference with the 1 sub hole transport layer (6141).

Referring again to FIG. 1, the second organic emission layer 62 may be disposed on the second sub-electrode 42. Like the first organic emission layer 61, the second organic emission layer 62 is formed by forming the second sub-electrode 42 after the first electrode 4, the first bank 5, and the second bank 9 are formed. ) can be formed on The second organic emission layer 62 may be formed after the first organic emission layer 61 is formed, but is not necessarily limited thereto.

The second organic light-emitting layer 62 includes an electron injection layer 621, an electron transport layer 622, a light-emitting layer 623, a first hole transport layer including a first sub-hole transport layer 6241 and a second sub-hole transport layer, 2 It may be provided including a hole transport layer and a hole injection layer. The first hole transport layer including the electron injection layer 621, the electron transport layer 622, the light emitting layer 623, the first sub hole transport layer 6241 and the second sub hole transport layer of the second organic light emitting layer 62, 2 A hole transport layer and a hole injection layer are sequentially formed in the second sub-pixel 22, and as described above, the second sub-hole transport layer, the second hole transport layer, and the hole injection layer of the second organic light-emitting layer 62 are It may be connected to each of the second sub hole transport layer 6142, the second hole transport layer 615, and the hole injection layer 616 of the first organic light emitting layer 61 and disposed as a common layer. Therefore, as shown in FIG. 1, the second sub-pixel 22 includes the second sub-hole transport layer 6142, the second hole transport layer 615, and the hole injection layer 616 of the first organic light-emitting layer 61. By being disposed in this common layer, it can perform the functions of the second sub hole transport layer, the second hole transport layer, and the hole injection layer of the second organic light emitting layer 62.

The electron injection layer 621, the electron transport layer 622, the light emitting layer 623, and the first sub hole transport layer 6241 of the second organic light emitting layer 62 disposed in the second sub pixel 22 have both ends. They can be provided to match each other.

More specifically, the light-emitting layer 623 of the second organic light-emitting layer 62 is formed by depositing the entire surface of the electron injection layer 621 and the electron transport layer 622 of the second organic light-emitting layer 62 as a common layer, and then forming the first to the first organic light-emitting layer 62. It can be entirely deposited over three sub-pixels (21, 22, and 23). Next, the first sub hole transport layer 6241 is entirely deposited on the upper surface of the light emitting layer 623 of the second organic light emitting layer 62, and then the electron injection layer 621 and the electron transport layer 622 of the second organic light emitting layer 62. ), the light emitting layer 623, and the first sub hole transport layer 6241 may be patterned to be disposed only in the second sub pixel 22.

In this way, the electron injection layer 621, the electron transport layer 622, the light emitting layer 623, and the first sub hole transport layer 6241 of the second organic light emitting layer 62 are patterned simultaneously, so the second organic light emitting layer ( Both ends of the electron injection layer 621, the electron transport layer 622, the light emitting layer 623, and the first sub hole transport layer 6241 of 62) may be implemented to match each other as shown in FIG. 1. Therefore, the display device 1 according to the first embodiment of the present application includes the electron injection layer 621, the electron transport layer 622, the light emitting layer 623, and the first sub hole transport layer ( 6241) at the same time, not only can the number of manufacturing processes be reduced compared to the case of patterning the electron injection layer, electron transport layer, light emitting layer, and first sub hole transport layer separately, but also the exposure, exposure, and It can be provided to prevent the overall luminous efficiency of the second organic light emitting layer 62 from being reduced by reducing the degree of exposure to etching gas and strip solution.

Next, the electron injection layer 621, the electron transport layer 622, the light emitting layer 623, and the first sub hole transport layer 6241 of the second organic light-emitting layer 62 patterned on the second sub-pixel 22 are covered. As shown, the second sub hole transport layer, the second hole transport layer, and the hole injection layer of the second organic light emitting layer 62 may be deposited sequentially. Here, the second sub hole transport layer, the second hole transport layer, and the hole injection layer of the second organic emission layer 62 are the second sub hole transport layer 6142 and the second hole injection layer of the first organic emission layer 61, as described above. Since it is connected to the hole transport layer 615 and the hole injection layer 616, the second sub-pixel 22 includes the second sub-hole transport layer 6142, the second hole transport layer 615, and the like of the first organic light-emitting layer 61. and a hole injection layer 616 may be disposed. Accordingly, the second sub hole transport layer 6142 of the first organic light emitting layer 61 is the top and both sides of the first sub hole transport layer 6241 of the second organic light emitting layer 62, both sides of the light emitting layer 623, It may be provided in a structure that covers both sides of the electron transport layer 622 and both sides of the electron injection layer 621.

Here, the second sub hole transport layer 6142 of the first organic light emitting layer 61 is the first sub hole transport layer 6142 of the second organic light emitting layer 62 disposed on the uppermost side among the layers on which the patterning process was performed in the second sub pixel 22. By being made of the same material as the hole transport layer 6241, it is possible to compensate for the first sub hole transport layer 6241 lost by the patterning process. Here, compensation means forming the second sub hole transport layer 6142 of the first organic light emitting layer 61 by the thickness of the first sub hole transport layer 6241 of the second organic light emitting layer 62 lost by the patterning process. This may mean that the energy level difference with the first sub hole transport layer 6241 whose energy level has been changed by the patterning process is reduced.

The third organic light-emitting layer 63 may be disposed on the third sub-electrode 43. The third organic light-emitting layer 63, like the first organic light-emitting layer 61 and the second organic light-emitting layer 62, has a first electrode 4, a first bank 5, and a second bank 9. After being formed, it may be formed on the third sub-electrode 43. The third organic emission layer 63 may be formed after the first organic emission layer 61 and the second organic emission layer 62 are formed, but is not necessarily limited thereto.

The third organic light-emitting layer 63 includes an electron injection layer 631, an electron transport layer 632, a light-emitting layer 633, a first hole transport layer including a first sub-hole transport layer 6341 and a second sub-hole transport layer, and a second sub-hole transport layer. 2 It may be provided including a hole transport layer and a hole injection layer. A first hole transport layer including the electron injection layer 631, the electron transport layer 632, the light emitting layer 633, the first sub hole transport layer 6341, and the second sub hole transport layer of the third organic light emitting layer 63, 2 The hole transport layer and the hole injection layer may be formed sequentially in the third sub-pixel 23. Here, the second sub hole transport layer, the second hole transport layer, and the hole injection layer of the third organic light emitting layer 63 are the second sub hole transport layer, the second hole transport layer, and the hole injection layer of the second organic light emitting layer 62, respectively. can be connected to As a result, the third sub-pixel 23 includes the second sub-hole transport layer 6142, the second hole transport layer 615, and the hole injection layer 616 of the first organic light-emitting layer 61, as shown in FIG. ) is disposed as a common layer and can perform the functions of the second sub hole transport layer, the second hole transport layer, and the hole injection layer of the third organic light emitting layer 63.

The electron injection layer 631, the electron transport layer 632, the light emitting layer 633, and the first sub hole transport layer 6341 of the third organic light-emitting layer 63 disposed in the third sub-pixel 23 have both ends connected to each other. It can be provided in a consistent manner.

More specifically, the light-emitting layer 633 of the third organic light-emitting layer 63 is formed by depositing the entire surface of the electron injection layer 631 and the electron transport layer 632 of the third organic light-emitting layer 63 as a common layer, and then forming the first to first layers. It can be entirely deposited over three sub-pixels (21, 22, and 23). Next, the first sub hole transport layer 6341 is entirely deposited on the upper surface of the light emitting layer 633 of the third organic light emitting layer 63, and then the electron injection layer 631 and the electron transport layer 632 of the third organic light emitting layer 63. ), the light emitting layer 633, and the first sub hole transport layer 6341 may be patterned to be disposed only in the third sub pixel 23.

In this way, the electron injection layer 631, the electron transport layer 632, the light emitting layer 633, and the first sub hole transport layer 6341 of the third organic light-emitting layer 63 are patterned simultaneously, so that the third organic light-emitting layer ( Both ends of the electron injection layer 631, the electron transport layer 632, the light emitting layer 633, and the first sub hole transport layer 6341 of 63) may be implemented to match each other as shown in FIG. 1. Therefore, the display device 1 according to the first embodiment of the present application includes the electron injection layer 631, the electron transport layer 632, the light emitting layer 633, and the first sub hole transport layer ( 6341) at the same time, not only can the number of manufacturing processes be reduced compared to the case of patterning the electron injection layer, electron transport layer, light emitting layer, and first sub hole transport layer separately, but also the exposure, exposure, and It can be provided to prevent the overall luminous efficiency of the third organic light-emitting layer 63 from being reduced by reducing the degree of exposure to etching gas and strip solution.

Next, the electron injection layer 631, the electron transport layer 632, the light emitting layer 633, and the first sub hole transport layer 6341 of the third organic light-emitting layer 63 patterned on the third sub-pixel 23 are covered. As shown, the second sub hole transport layer, the second hole transport layer, and the hole injection layer of the third organic light emitting layer 63 may be deposited sequentially. Here, the second sub hole transport layer, the second hole transport layer, and the hole injection layer of the third organic light emitting layer 63 are, as described above, the second sub hole transport layer, the second hole transport layer, and the hole injection layer of the second organic light emitting layer 62. and the hole injection layer, the second sub hole transport layer 6142, the second hole transport layer 615, and the hole injection layer 616 of the first organic light emitting layer 61 are disposed in the third sub pixel 23. It can be. Accordingly, the second sub hole transport layer 6142 of the first organic light emitting layer 61 is the top and both sides of the first sub hole transport layer 6341 of the third organic light emitting layer 63, both sides of the light emitting layer 633, Both sides of the electron transport layer 632 and both sides of the electron injection layer 631 may be covered.

Here, the second sub hole transport layer of the third organic light emitting layer 63, that is, the second sub hole transport layer 6142 of the first organic light emitting layer 61, is the uppermost layer among the layers on which the patterning process was performed in the third sub pixel 23. By being made of the same material as the first sub hole transport layer 6341 of the third organic light emitting layer 63 disposed, it is possible to compensate for the first sub hole transport layer 6341 lost by the patterning process. Here, compensation means forming the second sub hole transport layer 6142 of the first organic light emitting layer 61 by the thickness of the first sub hole transport layer 6341 of the third organic light emitting layer 63 lost by the patterning process. This may mean that the energy level difference with the first sub hole transport layer 6341 whose energy level has been changed by the patterning process is reduced.

As a result, the display device 1 according to the first embodiment of the present application includes the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, and the first sub hole transport layer of the first organic light emitting layer 61. (6141) is formed by patterning in the first sub-pixel 21, and the electron injection layer 621, the electron transport layer 622, the light-emitting layer 623, and the first sub hole transport layer ( 6241) is formed by patterning in the second sub-pixel 22, and the electron injection layer 631, electron transport layer 632, light-emitting layer 633, and first sub-hole transport layer 6341 of the third organic light-emitting layer 63 ) is patterned and formed in the third sub-pixel 23, the second sub-hole transport layer 6142, the second hole transport layer 615, and the hole injection layer 616 of the first organic light-emitting layer 61 are formed as a common layer. It can be provided by being sequentially deposited.

Accordingly, the display device 1 according to the first embodiment of the present application includes an electron injection layer 611, 621, 631 and an electron transport layer patterned and disposed in each of the first to third sub-pixels 21, 22, and 23. (612, 622, 632), the light emitting layer (613, 623, 633), and the first sub hole transport layer (6141, 6241, 6341) are provided to be spaced apart from each other, so that the second sub hole transport layer, the second hole transport layer, and the hole Even if the injection layer is provided as a common layer that connects the sub-pixels 21, 22, and 23, each of the first to third sub-pixels 21, 22, and 23 can emit light of different colors. For example, the first sub-pixel 21 emits red (R) light, the second sub-pixel 22 emits green (G) light, and the third sub-pixel 23 emits blue (B) light. It may be provided to emit light. However, it is not necessarily limited to this and may be equipped to emit light of various colors.

The first organic emission layer 61, the second organic emission layer 62, and the third organic emission layer 63 each emit red (R) light, green (G) light, and blue (B) light. When provided, the arrangement order of the first to third organic light-emitting layers 61, 62, and 63 with respect to the first sub-electrodes 41, 42, and 43 can be combined in various ways. The first organic emission layer 61, the second organic emission layer 62, and the third organic emission layer 63 each emit red (R) light, green (G) light, and blue (B) light. Accordingly, the display device 1 according to the first embodiment of the present application may not use a color filter, and thus the effect of reducing manufacturing costs can be expected.

As described above, the first to third organic light emitting layers 61, 62, and 63 each have an electron injection layer (611, 621, 631), an electron transport layer (612, 622, 632), and a light emitting layer (613, 623, 633). ), and the first sub hole transport layers 6141, 6241, and 6341 may be formed by patterning each of the first to third sub pixels 21, 22, and 23. More specifically, each of the electron injection layers (611, 621, 631), the electron transport layer (612, 622, 632), the light emitting layer (613, 623, 633), and the first sub hole transport layer (6141, 6241, 6341) A shield layer (SL) and a photoresist (PR) are deposited over the entire surface of the first to third sub-pixels 21, 22, and 23, and then deposited on the entire surface of the hole blocking layer 614, 624, 634. After sequentially stacking, each sub-pixel 21, 22, and 23 can be patterned and formed through an exposure process, a dry etching process, and a strip process using a stripper solution.

Here, in the exposure process of exposing the photoresist (PR) disposed on the upper side of each of the first to third organic light emitting layers 61, 62, and 63 to UV light, each light emitting layer 613, There may be a problem that 623, 633) are damaged due to heat caused by UV light, and the display device 1 according to the first embodiment of the present application has a first layer in contact with the upper surface of each of the light emitting layers 613, 623, and 633. By providing sub hole transport layers 6141, 6241, and 6341, respectively, the first sub hole transport layers 6141, 6241, and 6341 can be provided to protect the light emitting layers 613, 623, and 633 from UV light. Therefore, the display device 1 according to the first embodiment of the present application can prevent the light emitting layers 613, 623, and 633 from being damaged by UV light, thereby reducing the defect rate of the finished display device. .

In addition, in the display device 1 according to the first embodiment of the present application, each of the first sub hole transport layers 6141, 6241, and 6341 is disposed on the upper surface of each of the light emitting layers 613, 623, and 633, thereby forming a shield layer SL. ) to prevent the etching gas or stripper solution from penetrating into the light-emitting layer (613, 623, 633), thereby preventing the light-emitting layer (613, 623, 633) from being damaged by the etching gas or stripper solution. Here, the stripper solution may be at least one of a fluorine-based stripper solution and an aqueous stripper solution.

Referring again to FIG. 1, the second electrode 7 is disposed on the organic light-emitting layer 6. The second electrode 7 according to one embodiment may be an anode electrode, and is commonly formed in the first sub-pixel 21, the second sub-pixel 22, and the third sub-pixel 23. It is a common floor. The second electrode 7 is made of a transparent metal material (TCO, Transparent Conductive Material) such as ITO or IZO that can transmit light, or magnesium (Mg), silver (Ag), or magnesium (Mg) and silver (ag). It can be formed of a semi-transmissive conductive material such as an alloy.

An encapsulation layer 8 may be formed on the second electrode 7. The encapsulation layer 8 serves to prevent oxygen or moisture from penetrating into the organic light emitting layer 6 and the second electrode 7. To this end, the encapsulation layer 8 may include at least one inorganic layer and at least one organic layer.

For example, the encapsulation layer 8 may include a first inorganic layer, an organic layer, and a second inorganic layer. In this case, the first inorganic film is formed to cover the second electrode 7. The organic film is formed to cover the first inorganic film. The organic layer is preferably formed with a sufficient length to prevent particles from penetrating the first inorganic layer and entering the organic light-emitting layer 6 and the second electrode 7. The second inorganic film is formed to cover the organic film.

In Figure 1, for convenience of explanation, only the encapsulation layer 8 disposed on the second electrode 7 is shown. When the organic light emitting layer includes red, green, and blue light emitting layers that emit red (R), green (G), and blue (B) light, the red, green, and blue color filters are formed on the encapsulation layer (8). may not be placed in .

2A to 2P are schematic cross-sectional views of the manufacturing process of the display device according to the first embodiment of the present application. The display device 1 according to the first embodiment of the present application includes the electron injection layers 611, 621, 631 and the electron transport layer of the first to third organic light emitting layers 61, 62, and 63 through the following manufacturing process. 612, 622, 632), the light emitting layer (613, 623, 633), and both ends of the first sub hole transport layer (6141, 6241, 6341) can be aligned, and on the upper surface of each light emitting layer (613, 623, 633) By arranging the first sub hole transport layers 6141, 6241, and 6341, respectively, the first sub hole transport layers 6141, 6241, and 6341 protect each light emitting layer 613, 623, and 633 from UV light, etching gas, and stripper solution. It may be provided to do so.

2A to 2D, a first electrode 4, a first bank 5, and a second bank 9, which are cathode electrodes, are formed on the substrate 2 and the circuit element layer 3. In this state, the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, and the first sub hole transport layer 6141 of the first organic light emitting layer 61 are connected to the first to third sub pixels 21 and 22. After sequentially depositing the entire surface over , 23), a shield layer (SL) and a PR layer are sequentially coated on the upper surface of the first sub hole transport layer 6141, and a mask (M) is applied on the area of the first organic light-emitting layer 61. ) is placed, then an exposure process is performed to expose the PR layer in the remaining area to UV light. Accordingly, the characteristics of the PR layer except for the first organic light-emitting layer 61 region may be changed to be etched by the developer. The area of the first organic light-emitting layer 61 includes the electron injection layer 611, the electron transport layer 612, the light-emitting layer 613, and an area for forming the first sub hole transport layer 6141, which may be smaller than the width of the first sub electrode 41. The light emitting layer 613 of the first organic light emitting layer 61 may emit red (R) light, but is not limited thereto.

In the process of exposing the PR layer, the first sub hole transport layer 6141 disposed on the upper surface of the light-emitting layer 613 may block UV light from penetrating into the light-emitting layer 613. Accordingly, the display device 1 according to the first embodiment of the present application can prevent damage to the light emitting layer 613 caused by UV light used during the exposure process.

Next, referring to FIGS. 2E and 2F, a first removal process of removing the PR layer in the remaining area excluding the first organic light-emitting layer 61 area, and the shield layer in the remaining area excluding the first organic light-emitting layer 61 area. A secondary removal process is performed to remove (SL), the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, and the first sub hole transport layer 6141. The first removal process and the second removal process may be performed using at least one of etching gas, developer solution, and stripper solution. The PR layer can be corroded and removed by immersing it in a developer.

In the secondary removal process, the first organic light-emitting layer 61 and the shield layer (SL) of the remaining area, including the PR layer, on the first organic light-emitting layer 61 area may be removed using an etching gas or a stripper solution. The secondary removal process can remove a larger amount of organic matter including the shield layer (SL) than the first removal process by extending the exposure time to the etching gas or stripper solution compared to the first removal process. . Through this process, the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, and the first sub electrode 61 of the first organic light-emitting layer 61 are formed only on the top surface 41a of the first sub-electrode 41. The hole transport layer 6141 remains, and the remaining area includes the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, the first sub hole transport layer 6141, and the shield layer ( SL) and PR layers can be removed. The remaining area includes the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, and the first sub hole of the first organic light-emitting layer 61 on the upper surface 41a of the first sub-electrode 41. The area excluding the patterned portion of the transport layer 6141 may be an area containing the first bank 5, the second sub-pixel 22, the second bank 9, and the third sub-pixel 23. .

In the manufacturing process of the display device 1 according to the first embodiment of the present application, the first sub hole transport layer 6141 is disposed on the upper surface of the light emitting layer 613, and then the exposure process and removal process, that is, the patterning process, are performed as above. Therefore, the first sub hole transport layer 6141 can protect the light emitting layer 613 from UV light, etching gas, and stripper solution, thereby preventing damage to the light emitting layer 613 of the display device 1.

Next, referring to FIGS. 2G to 2J , a portion of the second organic emission layer 62 may be formed in the second sub-pixel 22 by repeating the processes of FIGS. 2B to 2F described above.

More specifically, the electron injection layer 621, the electron transport layer 622, the light emitting layer 623, and the first sub pixel of the second organic light-emitting layer 62 over the first to third sub-pixels 21, 22, and 23. After sequentially depositing the hole transport layer 6241 on the entire surface, a shield layer (SL) and a PR layer are sequentially coated on the upper surface of the first sub hole transport layer 6241, and a mask ( After positioning M), an exposure process is performed to expose the PR layer in the remaining area to UV light. Accordingly, the characteristics of the PR layer except for the second organic light-emitting layer 62 area may be changed to be etched by the developer. The area of the second organic light emitting layer 62 includes the electron injection layer 621, the electron transport layer 622, the light emitting layer 623, and an area for forming the first sub hole transport layer 6241, which may be smaller than the width of the second sub electrode 42. The light emitting layer 623 of the second organic light emitting layer 62 may emit green (G) light, but is not limited thereto.

In the process of exposing the PR layer, the first sub-hole transport layer 6241 disposed on the upper surface of the light-emitting layer 623 blocks UV light and protects the light-emitting layer 623 according to the above-described first organic light-emitting layer 61. The first sub hole transport layer 6141 protects the light emitting layer 613 from UV light. Accordingly, the display device 1 according to the first embodiment of the present application can prevent the light-emitting layer 623 of the second organic light-emitting layer 62 from being damaged by UV light used during the exposure process.

In this state, as shown in FIG. 2I, the PR layer in the remaining area except for the PR layer on the second organic light-emitting layer 62 area is removed using a developer, and a dry etching process or strip process is performed as shown in FIG. 2J. An electron injection layer 621, an electron transport layer 622, a light emitting layer 623, and a first sub electrode laminated on the area of the second organic light emitting layer 62, that is, on the upper surface 42a of the second sub electrode 42. A third removal process is performed to remove everything except the hole transport layer (6241). The electron injection layer 621 of the second organic light-emitting layer 62, which was disposed on the first sub-hole transport layer 6141 of the first organic light-emitting layer 61 in the first sub-pixel 21 by the third removal process, The electron transport layer 622, the light emitting layer 623, and the first sub hole transport layer 6241 may be removed. Here, the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, and the first sub hole transport layer 6141 of the first organic light-emitting layer 61 already formed in the first sub-pixel 21 are shown in FIG. 2J. As shown in , what may remain without being etched is that the dry etching process is completely performed with the PR layer remaining only in the second sub-pixel 22, and the second sub-pixel 22 with the PR layer remaining. Except for the shield layer (SL), the electron injection layer 621, the electron transport layer 622, the light emitting layer 623, and the first sub hole transport layer 6241 of the second organic light emitting layer 62 have the same thickness. Since it is deposited, if the dry etching process time is the same, it is etched to the same thickness, so the electron injection layer 611, electron transport layer 612, and light emitting layer 613 of the first organic light-emitting layer 61 already formed in the first sub-pixel 21. ), and the first sub hole transport layer 6141 may remain without being etched as shown in FIG. 2J.

Meanwhile, in the manufacturing process of the display device 1 according to the first embodiment of the present application, the first sub hole transport layer 6241 is disposed on the upper surface of the light emitting layer 623 of the second organic light emitting layer 62, and then exposed as above. Since the process, removal process, that is, the patterning process is performed, the first sub hole transport layer 6241 can protect the light emitting layer 623 from UV light, etching gas, and stripper solution, thereby protecting the light emitting layer 623 of the display device 1. Damage can be prevented.

Next, referring to FIGS. 2K to 2N , a portion of the third organic emission layer 63 may be formed in the third sub-pixel 23 by repeating the processes of FIGS. 2B to 2F described above.

More specifically, the electron injection layer 631, the electron transport layer 632, the light emitting layer 633, and the first sub pixel of the third organic light-emitting layer 63 over the first to third sub-pixels 21, 22, and 23. After sequentially depositing the hole transport layer 6341 on the entire surface, a shield layer (SL) and a PR layer are sequentially coated on the upper surface of the first sub hole transport layer 6341, and a mask ( After positioning M), an exposure process is performed to expose the PR layer in the remaining area to UV light. Accordingly, the characteristics of the PR layer except for the third organic light-emitting layer 63 area may be changed to be etched by the developer. The area of the third organic light-emitting layer 63 includes the electron injection layer 631, the electron transport layer 632, the light-emitting layer 633, and an area for forming the first sub hole transport layer 6341, which may be smaller than the width of the third sub electrode 43. The light emitting layer 633 of the third organic light emitting layer 63 may emit blue (B) light, but is not limited thereto.

In the process of exposing the PR layer, the first sub-hole transport layer 6341 disposed on the upper surface of the light-emitting layer 633 blocks UV light and protects the light-emitting layer 633 by using the first and second organic light-emitting layers described above. It is the same as the first sub hole transport layers (6141, 6241) of (61, 62) protecting the light emitting layers (613, 623) from UV light. Accordingly, the display device 1 according to the first embodiment of the present application can prevent damage to the light-emitting layer 633 of the third organic light-emitting layer 63 due to UV light used during the exposure process.

In this state, as shown in FIG. 2M, the PR layer in the remaining area except for the PR layer on the third organic light-emitting layer 63 area is removed using a developer, and a dry etching process or strip process is performed as shown in FIG. 2N. The electron injection layer 631, the electron transport layer 632, and the light-emitting layer of the third organic light-emitting layer 63 are stacked on the area of the third organic light-emitting layer 63, that is, on the upper surface 43a of the third sub-electrode 43. (633), and a fourth removal process is performed to remove everything except the first sub hole transport layer (6341). The electron injection layer 631 of the third organic light-emitting layer 63, which was disposed on the first sub-hole transport layer 6141 of the first organic light-emitting layer 61 in the first sub-pixel 21 by the fourth removal process, The electron transport layer 632, the light emitting layer 633, and the first sub hole transport layer 6341 may be removed. Likewise, the electron injection layer 631 of the third organic light-emitting layer 63 was disposed on the first sub-hole transport layer 6241 of the second organic light-emitting layer 62 in the second sub-pixel 22 by the fourth removal process. ), the electron transport layer 632, the light emitting layer 633, and the first sub hole transport layer 6341 can also be removed at the same time.

The manufacturing process of the display device 1 according to the first embodiment of the present application includes disposing the first sub hole transport layer 6341 on the upper surface of the light emitting layer 633 of the third organic light emitting layer 63, followed by the exposure process as above, Since the removal process, that is, the patterning process, is performed, the first sub hole transport layer 6341 can protect the light-emitting layer 633 from UV light, etching gas, and stripper solution, thereby preventing damage to the light-emitting layer 633 of the display device 1. It can be prevented.

As a result, the display device 1 according to the first embodiment of the present application has a first sub hole transport layer on the upper surface of each of the light emitting layers 613, 623, and 633 of the first to third organic light emitting layers 61, 62, and 63. By arranging (6141, 6241, and 6341) respectively, the light emitting layers (613, 623, and 633) can be protected from UV light, etching gas, and stripper solution used during the patterning process of each organic light emitting layer (61, 62, and 63). It is possible to prevent the device characteristics of the light emitting layers 613, 623, and 634 from being deteriorated.

Next, referring to FIGS. 2O and 2P, the electron injection layer 611, the electron transport layer 612, of the first organic light-emitting layer 61 are patterned for each of the first to third sub-pixels 21, 22, and 23, respectively. The light emitting layer 613, the first sub hole transport layer 6141, the electron injection layer 621 of the second organic light emitting layer 62, the electron transport layer 622, the light emitting layer 623, the first sub hole transport layer 6241, and The second sub hole transport layer of the first organic light emitting layer 61 covers the electron injection layer 631, the electron transport layer 632, the light emitting layer 633, and the first sub hole transport layer 6341 of the third organic light emitting layer 63. By sequentially depositing the entire surface (6142), the second hole transport layer 615, the hole injection layer 616, the second electrode 7, and the encapsulation layer 8, the manufacturing process can be partially completed.

Here, the second sub-hole transport layer 6142, the second hole transport layer 615, and the hole injection layer 616 of the first organic light-emitting layer 61 are connected to the first sub-pixel 21, the second sub-pixel 22, And since it is a common layer deposited on the entire surface of the third sub-pixel 23, it can be the second sub hole transport layer, the second hole transport layer, and the hole injection layer of the second organic light-emitting layer 62, and the third organic light-emitting layer ( 63) may be the second sub hole transport layer, the second hole transport layer, and the hole injection layer.

Accordingly, the second sub hole transport layer 6142 deposited on the entire surface of the first to third sub pixels 21, 22, and 23 is formed on the top and side surfaces of each of the first sub hole transport layers 6141, 6241, and 6341, and the light emitting layer. It can cover the side surfaces of (613, 623, 633), the side surfaces of the electron transport layer (612, 622, 632), and the side surface of the electron injection layer (611, 621, 631).

The display device 1 according to the first embodiment of the present application includes the second sub hole transport layer 6142, the second hole transport layer 615, and the hole injection layer 616 of the organic light emitting layer 6. By arranging a common layer that covers all of the sub-pixels 21, 22, and 23, the number of manufacturing processes can be reduced compared to the case of forming a second sub-hole transport layer, a second hole transport layer, and a hole injection layer for each sub-pixel. This can have the effect of reducing the tact time of the display device.

Meanwhile, as shown in Figure 2p, the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, and the first sub hole transport layer 6141 of the first organic light emitting layer 61 are the second organic light emitting layer. It may be arranged to be spaced apart from each of the electron injection layer 621, the electron transport layer 622, the light emitting layer 623, and the first sub hole transport layer 6241 of (62). Accordingly, even if an electric field is formed between the first sub-electrode 41 and the second electrode 7, no leakage current is generated toward the second sub-pixel 22, so the second sub-pixel 22 does not emit light. You can. Likewise, even if an electric field is formed between the second sub-electrode 42 and the second electrode 7, no leakage current occurs toward the first sub-pixel 21, so the first sub-pixel 21 may not emit light. there is.

In addition, the electron injection layer 631, the electron transport layer 632, the light emitting layer 633, and the first sub hole transport layer 6341 of the third organic light-emitting layer 63 are the electron injection layers of the second organic light-emitting layer 62. 621, the electron transport layer 622, the light emitting layer 623, and the first sub hole transport layer 6241 may be arranged to be spaced apart from each other. Accordingly, even if an electric field is formed between the third sub-electrode 43 and the second electrode 7, no leakage current occurs toward the second sub-pixel 22, so the second sub-pixel 22 does not emit light. You can.

As a result, the display device 1 according to the first embodiment of the present application includes the first to third organic light emitting layers 61, 62, and 63, each of the electron injection layers 611, 621, and 631, and the electron transport layer 612. 622, 632, light emitting layers 613, 623, 633, and first sub hole transport layers 6141, 6241, 6341 are provided to be spaced apart from each other, so that color mixing occurs between adjacent sub pixels emitting light of different colors. can be prevented.

Figure 3 is a schematic structural diagram of part A of Figure 1, Figure 4 is a graph showing the ratio of oxygen contained in the first sub hole transport layer and the second sub hole transport layer of Figure 3, and Figure 5 is part B of Figure 3. It is a schematic structural diagram, and FIG. 6 is a graph showing the voltage change according to driving of the organic light emitting layer of the display device according to the first embodiment of the present application.

3 to 6, in the display device 1 according to the first embodiment of the present application, the first sub hole transport layers 6141, 6241, and 6341 each have upper surfaces of the light emitting layers 613, 623, and 633, respectively. Since the patterning process including exposure and etching processes is performed in the covered state, the energy level of the second sub hole transport layer 6142 disposed in a common layer with the first sub hole transport layer 6141, 6241, and 6341, that is, the energy Level differences may occur.

3 shows the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, and the first sub-pixel 21 of the first organic light-emitting layer 61 that emits red (R) light. A first hole transport layer 614 including a hole transport layer 6141 and a second sub hole transport layer 6142, a second hole transport layer 615, and a hole injection layer 616, and their respective energy levels are schematically It is shown. As shown in FIG. 3, the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, the first sub hole transport layer 6141, and the second sub hole transport layer constituting the first organic light emitting layer 61. 6142, the second hole transport layer 615, and the hole injection layer 616 each have different energy levels.

More specifically, the LUMO energy level of the electron transport layer 612 may be greater than the LUMO energy level of the electron injection layer 611, and the HOMO energy level of the electron transport layer 612 may be greater than the HOMO energy level of the electron injection layer 611. It can be big. The LUMO energy level of the light-emitting layer 613 may be smaller than the LUMO energy level of the electron transport layer 612, and the HOMO energy level of the light-emitting layer 613 may be greater than the HOMO energy level of the electron transport layer 612. The LUMO energy level of the first sub hole transport layer 6141 may be greater than the LUMO energy level of the light emitting layer 613, and the HOMO energy level of the first sub hole transport layer 6141 may be greater than the HOMO energy level of the light emitting layer 613. there is. The LUMO energy level of the second sub hole transport layer 6142 may be greater than the LUMO energy level of the first sub hole transport layer 6141, and the HOMO energy level of the second sub hole transport layer 6142 may be greater than that of the first sub hole transport layer 6141. ) may be larger than the HOMO energy level of ). The LUMO energy level of the second hole transport layer 615 may be smaller than the LUMO energy level of the second sub hole transport layer 6142, and the HOMO energy level of the second hole transport layer 615 may be lower than that of the second sub hole transport layer 6142. It can be larger than the HOMO energy level. The LUMO energy level of the hole injection layer 616 may be lower than the LUMO energy level of the second hole transport layer 615, and the HOMO energy level of the hole injection layer 616 may be lower than the HOMO energy level of the second hole transport layer 615. It can be small.

Here, the difference in LUMO energy level at the boundary of each layer may affect the driving voltage of the electron injection layer 611, electron transport layer 612, and light emitting layer 613, which are the electron moving parts, and the hole moving part The hole injection layer 616, the second hole transport layer 615, the second sub hole transport layer 6142, the first sub hole transport layer 6141, and the light emitting layer 613 have HOMO energy levels at the boundaries of each layer. The difference may affect the driving voltage. Therefore, if the difference between the LUMO energy levels of each layer in the electron movement part is large, the driving voltage may increase because the electrons cannot move smoothly toward the light-emitting layer 613, and the difference in the LUMO energy levels of each layer in the electron movement part is small. If so, electrons can move smoothly toward the light emitting layer 613, so the driving voltage can be reduced. Likewise, if the difference in HOMO energy levels of each layer is large in the hole movement portion, the driving voltage may increase because the holes cannot move smoothly toward the light-emitting layer 613, and the difference in HOMO energy levels of each layer in the hole movement portion is small. If so, holes can move smoothly toward the light emitting layer 613, so the driving voltage can be reduced.

In the display device 1 according to the first embodiment of the present application, a patterning process such as an exposure process, a dry etching process, etc. is performed after the first sub hole transport layer 6141 is disposed on the upper surface of the light emitting layer 613, so that the first sub hole transport layer 6141 is disposed on the upper surface of the light emitting layer 613. The hole transport layer 6141 blocks UV light to prevent deterioration of the light-emitting layer 613, thereby preventing damage to the light-emitting layer 613 as well as preventing damage to the light-emitting layer 613 from etching gas or stripper solution. The device 1 is provided as seen in the above-described manufacturing process.

Meanwhile, since the exposure process is performed on the first sub hole transport layer 6141, the first sub hole transport layer 6141 may be deteriorated. Accordingly, the LUMO energy level of the first sub hole transport layer 6141 may increase and the HOMO energy level may decrease. That is, as shown in FIG. 3, the first sub hole transport layer 6141 can expand in the upward and downward directions. Accordingly, the energy level difference between the first sub hole transport layer 6141 and the layer disposed on the top surface of the first sub hole transport layer 6141 may increase.

However, the display device 1 according to the first embodiment of the present application arranges a second sub hole transport layer 6142 made of the same material on the upper surface of the first sub hole transport layer 6141 on which the patterning process was performed, Compared to the case where a layer made of another material is disposed on the upper surface of the first sub hole transport layer 6141, the energy gap between the first sub hole transport layer 6141 and the second sub hole transport layer 6142 can be reduced.

More specifically, the difference between the LUMO energy level of the first sub hole transport layer 6141 and the LUMO energy level of the second sub hole transport layer 6142 may be 0.2 eV or more and 0.5 eV or less. Additionally, the difference between the HOMO energy level of the first sub hole transport layer 6141 and the HOMO energy level of the second sub hole transport layer 6142 may be 0.2 eV or more and 0.5 eV or less.

In addition, the display device 1 according to the first embodiment of the present application arranges a second sub hole transport layer 6142 made of the same material on the upper surface of the first sub hole transport layer 6141, thereby performing the patterning process. By compensating for the lost first sub-hole transport layer 6141, the luminous efficiency of the first organic light-emitting layer 61 can be prevented from being reduced.

Referring again to FIG. 3, the second hole transport layer 615 disposed to cover the second sub hole transport layer 6142 may be made of a different material from the second sub hole transport layer 6142. The second hole transport layer 615 is a material necessary for device characteristics, and may be a material that can effectively inject holes into the second sub hole transport layer 6142.

More specifically, as shown in FIG. 3, the second hole transport layer 615 is disposed between the hole injection layer 616 and the second sub hole transport layer 6142 and is disposed on the upper surface of the second sub hole transport layer 6142. do. Here, the HOMO energy level of the second hole transport layer 615 has a difference of about 0.11 eV from the LUMO energy level of the hole injection layer 616, and the HOMO energy level of the second sub hole transport layer 6142 and the hole injection layer 616 ) It can be seen that the LUMO energy levels differ by about 0.35 eV. That is, when the second hole transport layer 615 is made of the same material as the second sub-hole transport layer 6142, an energy level difference of about 0.35 eV occurs with the hole injection layer 616, as described above, and this energy level difference occurs. is larger than the energy level difference of about 0.11 eV when the second hole transport layer 615 is made of a different material from the second sub hole transport layer 6142. If the energy level difference is large, holes cannot move smoothly from the hole injection layer to the second hole transport layer, so holes are accumulated between the interface of the hole injection layer and the second hole transport layer, which can increase the driving voltage of the entire organic light-emitting layer. . If the driving voltage of the organic light-emitting layer increases, the lifespan of the light-emitting device may be shortened.

As a result, the display device 1 according to the first embodiment of the present application arranges the second hole transport layer 615 with a different material from the second sub hole transport layer 6142, thereby reducing the energy between the hole injection layer 616 and the second hole transport layer 615. Since the level difference can be reduced, holes are smoothly moved from the hole injection layer 616 to the second sub hole transport layer 6142 through the second hole transport layer 615, thereby preventing the lifespan of the light emitting device from being shortened. It can be.

Referring to FIG. 4, in the display device 1 according to the first embodiment of the present application, the first sub hole transport layer 6141 is placed on the upper surface of the light emitting layer 613 and then subjected to a patterning process such as an exposure process and a dry etching process. Since this is provided so that the first sub hole transport layer 6141 is exposed to air, the first sub hole transport layer 6141 may contain oxygen (O ₂ ) in the air.

Accordingly, the ratio of oxygen (O ₂ ) contained inside the first sub hole transport layer 6141 and the second sub hole transport layer 6142 of the display device 1 according to the first embodiment of the present application is equal to that of the first sub hole transport layer 6142. It can be higher than when the hole transport layer and the second sub-hole transport layer are continuously deposited in a vacuum without a patterning process. For example, when the first sub hole transport layer and the second sub hole transport layer are continuously deposited in a vacuum condition without a patterning process, the ratio of oxygen (O ₂ ) contained within the first sub hole transport layer and the second sub hole transport layer is 2. While it is less than %, the ratio of oxygen (O ₂ ) contained inside the first sub hole transport layer 6141 and the second sub hole transport layer 6142 of the display device 1 according to the first embodiment of the present application is It can be between 3% and 16%. Figure 4 shows this graphically.

In Figure 4, the horizontal axis represents the thickness of the first hole transport layer, that is, the combined thickness of the first sub hole transport layer and the second sub hole transport layer, and the vertical axis represents the ratio of oxygen (O ₂ ) contained in the first hole transport layer. indicates. Here, L1 is a graph showing the ratio of oxygen (O ₂ ) in the first hole transport layer when the first sub hole transport layer and the second sub hole transport layer are continuously deposited in a vacuum condition without a patterning process, and L2 is the graph of the first sub hole transport layer of the present application. 1 This is a graph showing the ratio of oxygen (O ₂ ) in the first hole transport layer 614 of the display device 1 according to the embodiment. As shown in FIG. 4, since the first sub-hole transport layer and the second sub-hole transport layer of L1 are continuously deposited in a vacuum state, the proportion of oxygen (O ₂ ) in the first hole transport layer is barely about 1%. On the other hand, in L2, the proportion of oxygen (O ₂ ) in the first hole transport layer 614 is about 3% to 16%, which is higher than L1, and in particular, 100 Å or more close to the top surface of the first sub hole transport layer 6141. The highest oxygen (O ₂ ) ratio is shown below 200 Å.

In this way, the display device 1 according to the first embodiment of the present application confirms the ratio of oxygen (O ₂ ) contained in the first hole transport layer 614, and thus determines the first sub-hole transport layer 6141 made of the same material. ) and the second sub hole transport layer 6142. The ratio of oxygen (O ₂ ) contained in the first hole transport layer 614 can be confirmed through an analysis method such as EDS.

In addition, as shown in FIG. 4, the display device 1 according to the first embodiment of the present application has a surface closer to the center of the first hole transport layer 614 than the interface formed by the first hole transport layer 614 and other layers. It can be provided to increase the oxygen content.

Meanwhile, referring to FIG. 3, the display device 1 according to the first embodiment of the present application has the thickness (T1, shown in FIG. 3) of the first sub hole transport layer 6141 and the second sub hole transport layer 6142. The thickness (T2, shown in FIG. 3) may be provided to be the same. For example, if the conventional hole transport layer is provided as one and its thickness is 400 Å, the present display device 1 is configured so that the combined thickness of the first sub hole transport layer 6141 and the second sub hole transport layer 6142 is 400 Å. It can be provided. That is, the present display device 1 can be formed by dividing one conventional hole transport layer into two. Accordingly, the thickness T1 of the first sub hole transport layer 6141 may be 200 Å, and the thickness T2 of the second sub hole transport layer 6142 may be 200 Å. However, it is not necessarily limited to this, and the thickness T1 of the first sub hole transport layer 6141 may be 100 Å or more, and the thickness T2 of the second sub hole transport layer 6142 may be 300 Å or less. If the thickness T1 of the first sub hole transport layer 6141 is less than 100 Å, the effect of protecting the light emitting layer 613 from UV light, etching gas, and stripper solution used in the patterning process is reduced.

In the display device 1 according to the first embodiment of the present application, the combined thickness of the first sub hole transport layer and the second sub hole transport layer for each of the first to third sub pixels 21, 22, and 23 is the same at 400 Å. It is provided so that the thickness (T2) of the second sub hole transport layer (6142) varies depending on the thickness (T1) of the first sub hole transport layer (6141).

If the combined thickness of the first sub hole transport layer 6141 and the second sub hole transport layer 6142 is different for each sub pixel (21, 22, 23), the gap between the first electrode 4 and the second electrode 7 is sub This is because different electric fields are formed for each sub-pixel. When different electric fields are formed for each sub-pixel, only the luminance of a specific color increases, which may cause the problem of non-uniform luminance when viewed as a whole.

Therefore, in the display device 1 according to the first embodiment of the present application, the combined thickness of the first sub hole transport layer 6141 and the second sub hole transport layer 6142 is the same for each sub pixel 21, 22, and 23. By configuring it, it can be provided to prevent the overall luminance from becoming non-uniform.

5 shows that the first sub hole transport layer 6141 and the second sub hole transport layer 6142 are made of the same material, so that holes are formed between the interface of the first sub hole transport layer 6141 and the second sub hole transport layer 6142. This shows that it moves smoothly without accumulating.

As described above, since the patterning process proceeds with the first sub hole transport layer 6141 deposited on the upper surface of the light emitting layer 613, the first sub hole transport layer 6141 expands due to exposure to air, thereby forming the first sub hole transport layer 6141. 1 Injection of holes into the sub hole transport layer 6141 may become difficult. If a layer having a different material is disposed on the upper surface of the first sub hole transport layer, holes may accumulate between the interface of the first sub hole transport layer and the other material layer, which may cause a problem of increasing the driving voltage for light emission.

However, in the display device 1 according to the first embodiment of the present application, the second sub hole transport layer 6142 of the same material is disposed on the upper surface of the first sub hole transport layer 6141, so that the driving voltage is reduced almost over time. The state can be maintained the same as the initial driving voltage without change. Figure 6 shows this graphically.

In Figure 6, the horizontal axis represents time, and the vertical axis represents change in driving voltage. Here, L3 is a graph showing the change in driving voltage over time when a patterning process is performed on the light-emitting layer, the light-emitting layer is exposed to the air, and a hole transport layer is deposited on the upper surface of the light-emitting layer, and L4 is a graph according to the first embodiment of the present application. A patterning process is performed with the first sub hole transport layer 6141 deposited on the upper surface of the light emitting layer 613 of the display device 1, and a second sub hole transport layer of the same material is deposited on the upper surface of the first sub hole transport layer 6141. This is a graph showing the change in driving voltage over time when the transport layer 6142 is deposited. As shown in FIG. 6, in L3, the light-emitting layer is exposed to the air and a hole transport layer made of a different material from the light-emitting layer is deposited. As described above, holes accumulate at the interface between the light-emitting layer and the hole transport layer made of a different material over time. It can be seen that the driving voltage increases. On the other hand, in L4, even if the first sub hole transport layer 6141 is exposed to the air, the second sub hole transport layer 6142 of the same material is disposed on the upper surface of the first sub hole transport layer 6141, so the second sub hole transport layer 6142 ) to the first sub hole transport layer 6141, the movement of holes is smooth, so it can be seen that there is almost no change in driving voltage over time.

As a result, the display device 1 according to the first embodiment of the present application has a second sub hole transport layer 6142 made of the same material even if the first sub hole transport layer 6141 is exposed to the air. ), it is possible to prevent holes from accumulating at the interface of the first sub hole transport layer 6141 and the second sub hole transport layer 6142, thereby preventing the driving voltage from increasing, thereby preventing the light emitting layer 613 ) can be provided to prevent the device lifespan from being shortened.

Figure 7 is a graph showing improvement in the lifespan of the organic light emitting layer of the display device according to the first embodiment of the present application.

In Figure 7, the horizontal axis represents time, and the vertical axis represents initial luminance converted to 100%. Here, L5 is a graph showing the lifespan of the light-emitting layer when a patterning process is performed on the upper surface of the light-emitting layer and the hole transport layer is provided as one layer and deposited on the upper surface of the light-emitting layer, and L6 is a graph according to the first embodiment of the present application. The patterning process is performed with the first sub hole transport layer 6141 of the display device 1 covering the light emitting layer 613, and the second sub hole transport layer 6142 made of the same material covers the first sub hole transport layer 6142. This is a graph showing the lifespan of the light emitting layer when covered. As shown in Figure 7, when the luminance of L5 is about 78%, the device life of the light emitting layer is about 1 hour, while for L6, when the luminance is about 78%, the device life of the light emitting layer is about 50 hours.

As a result, in the display device 1 according to the first embodiment of the present application, the patterning process is performed with the first sub hole transport layer 6141 covering the light emitting layer 613, and the first sub hole transport layer 6141 and The second sub hole transport layer 6142 of the same material is disposed to cover the first sub hole transport layer 6141, compared to the case where the patterning process is performed on the upper surface of the light-emitting layer and a hole transport layer of a different material is disposed on the upper surface of the light-emitting layer. The device lifespan of the light emitting layer 613 can be improved.

Figure 8 is a schematic cross-sectional view of a display device according to a second embodiment of the present application.

Referring to FIG. 8, the display device 1 according to the second embodiment of the present application includes the first sub hole transport layers 6142, 6121, and 6341 of each of the first to third organic light emitting layers 61, 62, and 63. It is the same as the display device 1 according to FIG. 1 described above except that the thickness is different. Accordingly, the same reference numerals are assigned to the same components, and only the different components will be described below.

In the case of the display device according to FIG. 1 described above, the first sub hole transport layers 6142, 6121, and 6341 of each of the first to third organic light emitting layers 61, 62, and 63 are formed to have the same thickness.

On the other hand, in the case of the display device according to FIG. 8, the thickness of the first sub hole transport layer 6142 of the first organic light emitting layer 61 is the same as that of the second sub hole transport layer 6241 of the second organic light emitting layer 62. 3 It is thicker than the thickness of the third sub hole transport layer 6341 of the organic light emitting layer 63, and the thickness of the second sub hole transport layer 6241 of the second organic light emitting layer 62 is thicker than the thickness of the third sub hole transport layer 6341 of the third organic light emitting layer 63. It is provided thicker than the thickness of the sub hole transport layer 6341. Accordingly, the display device 1 according to the second embodiment of the present application can implement micro cavity characteristics for each of the first to third sub-pixels 21, 22, and 23.

Meanwhile, the second sub holes of the first organic light emitting layer 61 are disposed as a common layer on the upper side of the first sub hole transport layers 6142, 6241, and 6341 of each of the first to third organic light emitting layers 61, 62, and 63. The transport layer 6142, the second hole transport layer 615, and the hole injection layer 616 are the first sub hole transport layers 6141, 6241, and 6341 of the first to third organic light emitting layers 61, 62, and 63, respectively. As they are provided with different thicknesses, there may be a step along the profile of the first sub hole transport layer (6141, 6241, 6341).

The first organic light-emitting layer 61 may emit red light, the second organic light-emitting layer 62 may emit green light, and the third organic light-emitting layer 63 may emit blue light, but is necessarily limited to this. It doesn't work. However, the thickness of the first sub hole transport layer disposed on the organic light emitting layer that emits long wavelength light, such as red light, may be thicker than the thickness of the first sub hole transport layer disposed on the organic light emitting layer that emits short wavelength light, such as blue light. You can.

FIG. 9 is a schematic cross-sectional view of a display device according to a third embodiment of the present application, and FIGS. 10A to 10J are schematic cross-sectional views of a manufacturing process of a display device according to a third embodiment of the present application.

Referring to FIGS. 9 to 10J, the display device 1 according to the third embodiment of the present application includes the first to third organic light emitting layers 61, 62, and 63 and each of the electron injection layers 611, 621, and 631. , It is the same as the display device 1 according to FIG. 1 described above, except that the structures of the electron transport layers 612, 622, and 632, and the first sub hole transport layers 6141, 6241, and 6341 are changed. Accordingly, the same reference numerals are assigned to the same components, and only the different components will be described below.

In the case of the display device according to FIG. 1 described above, the first to third organic light-emitting layers 61, 62, and 63 each have electron injection layers 611, 621, and 631 and electron transport layers 612, 622, and 632 in each sub. Each pixel 21, 22, and 23 is arranged to be spaced apart from each other. In addition, the first sub hole transport layers 6141, 6241, and 6341 of each of the first to third organic light emitting layers 61, 62, and 63 are provided to coincide with both ends of the light emitting layers 613, 623, and 633, respectively, to form a light emitting layer ( 613, 623, 633) are disposed only on the upper surface of each, and do not contact the electron transport layers 612, 622, and 632 disposed on the lower surface of the light emitting layers 613, 623, and 633.

On the other hand, in the case of the display device according to the third embodiment of FIG. 9, the first to third organic light emitting layers 61, 62, and 63 each have electron injection layers 611, 621, 631 and electron transport layers 612, 622, 632) are provided to be connected to each other. Therefore, the display device 1 according to the third embodiment of the present application includes the electron injection layer 611, the electron transport layer 612, the second sub-hole transport layer 6142, and the second hole transport layer of the first organic light-emitting layer 61. The transport layer 615 and the hole injection layer 616 are the electron injection layer 621, the electron transport layer 622, the second sub-hole transport layer, the second hole transport layer, and the hole injection layer of the second organic light-emitting layer 62, respectively. and are connected to each other, and the electron injection layer 621, the electron transport layer 622, the second sub hole transport layer, the second hole transport layer, and the hole injection layer of the second organic light emitting layer 62 are of the third organic light emitting layer 63. It may be provided to be connected to each of the electron injection layer 631, the electron transport layer 632, the second sub hole transport layer, the second hole transport layer, and the hole injection layer. Here, the second sub hole transport layer 6142, the second hole transport layer 615, and the hole injection layer 616 of the first organic light emitting layer 61 are the first to third sub hole transport layers 6142, 615, and 616 of the first organic light emitting layer 61. Since it is a common layer formed across the pixels 21, 22, and 23, it can be the second sub hole transport layer, the second hole transport layer, and the hole injection layer of the second organic light emitting layer 62, as shown in FIG. 9, It may be a second sub hole transport layer, a second hole transport layer, and a hole injection layer of the third organic light emitting layer 63.

As a result, the display device 1 according to the third embodiment of the present application includes electron injection layers 611, 621, 631 and electron transport layers 612, respectively, of the first to third organic light emitting layers 61, 62, and 63. By forming the elements 622 and 632 to be connected to each other, the number of manufacturing processes can be reduced compared to the case where the electron injection layer and the electron transport layer are formed separately for each sub-pixel 21, 22, and 23, thereby reducing the tact time of the completed display device. It can have a certain effect.

Meanwhile, the display device 1 according to the third embodiment of the present application includes electron injection layers 611, 621, 631, and electron transport layers 612 and 622 of the first to third organic light emitting layers 61, 62, and 63. 632), the second sub hole transport layer (6142, 6242, 6342), the second hole transport layer, and the hole injection layer are connected to each other, so that the light emitting layer ( 613, 623, and 633) and the first sub hole transport layer 6141, 6241, and 6341 may be arranged to be spaced apart from each other. Accordingly, the display device 1 according to the third embodiment of the present application includes the light emitting layers 613, 623, 633 of the first to third organic light emitting layers 61, 62, and 63 and the first sub hole transport layers 6141 and 6241. , 6341) are arranged to be spaced apart from each other for each of the first to third sub-pixels 21, 22, and 23, so that each of the first to third sub-pixels 21, 22, and 23 is equipped to emit light of different colors. You can.

Referring again to FIG. 9, in the display device 1 according to the third embodiment of the present application, the first sub hole transport layer 6141 of the first organic light-emitting layer 61 is the light-emitting layer 613 of the first organic light-emitting layer 61. ) and may be provided to contact the upper surface of the electron transport layer 612 disposed on the lower surface of the first organic light-emitting layer 61 while covering the upper and side surfaces of the first organic light-emitting layer 61.

In the case of the display device of FIG. 1 described above, the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, and the first sub hole transport layer 6141 are sequentially deposited and then patterned using a dry etching process. On the other hand, in the case of the display device of FIG. 9, the electron injection layer 611, the electron transport layer 612, the shield layer (SL), and the PR layer are sequentially deposited, and then the shield layer (SL) and PR layer are removed. , Since the light emitting layer 613 and the first sub hole transport layer 6141 are deposited in the removed groove and then the remaining shield layer (SL) and PR layer are removed using a lift-off process, such structural differences may occur. That is, the display device in FIG. 1 is a display device manufactured using a dry etching process, and the display device in FIG. 9 is a display device manufactured using a lift-off process, so the first sub hole transport layer 6141 is the light emitting layer 613. ) or the first sub hole transport layer 6141 covers both the top and side surfaces of the light-emitting layer 613.

Hereinafter, the display device 1 according to the third embodiment of the present application shown in FIG. 9 will be combined with the manufacturing process of the display device 1 according to the third embodiment of the present application shown in FIGS. 10A to 10J. The above differences will be explained in detail.

First, referring to FIGS. 10A to 10B, the first electrode 4, the first bank 5, and the second bank 9 are formed on the substrate 2 and the circuit element layer 3. In, after sequentially applying the electron injection layer 611, the electron transport layer 612, the shield layer (SL), and the PR layer of the first organic light-emitting layer 61, the first deposition hole (H1, shown in Figure 10c) A mask (M, shown in FIG. 10B) is placed in the area where the mask is to be formed, and then the remaining part is exposed. Accordingly, the characteristics of the remaining areas of the PR layer, excluding the area where the first deposition hole H1 will be formed, may be changed so that they are not etched by the developer.

Since the electron injection layer 611 and the electron transport layer 612 of the first organic light-emitting layer 61 are entirely deposited as a common layer as described above, the electron injection layer 621 and the electron transport layer of the second organic light-emitting layer 62 (622), may be the electron injection layer 631 and the electron transport layer 632 of the third organic light-emitting layer 63. That is, the electron injection layer 611 and the electron transport layer 612 of the first organic light-emitting layer 61 are the electron injection layer 621 and the electron transport layer 622 of the second organic light-emitting layer 62, and the third organic light-emitting layer 62. It may be connected to each of the electron injection layer 631 and the electron transport layer 632 of the light emitting layer 63.

The first deposition hole (H1) is a hole for forming the light-emitting layer 613 and the first sub-hole transport layer 6141 of the first organic light-emitting layer 61, and will ultimately become the upper surface of the electron transport layer 612. You can. The PR layer may be a photoresist layer. The light-emitting layer 613 may be a red light-emitting layer that emits red (R) light when an electric field is generated.

Next, referring to FIG. 10C, a first removal process is performed in which the PR layer located in the area where the first deposition hole H1 is to be formed is removed using a developer. The PR layer removed by the developer can be corroded and removed by being immersed in the developer.

Next, referring to FIG. 10D, a secondary removal process is performed in which the shield layer SL located in the area where the first deposition hole H1 is to be formed is removed using a developer. At this time, in the second removal process, the time for immersion in the developer is increased compared to the first removal process, thereby increasing the volume of the shield layer (SL) removed compared to the first removal process, resulting in a so-called undercut. UC) area can be formed. Accordingly, the width of the shield layer SL removed by the second removal process may be wider than the width of the PR layer removed by the first removal process.

Next, referring to FIG. 10E, the light emitting layer 613 of the first organic light emitting layer 61 is formed on the electron transport layer 612 disposed in the first deposition hole H1. For example, the light-emitting layer 613 of the first organic light-emitting layer 61 can be formed by supplying and depositing organic materials in various ways from outside the PR layer toward the electron transport layer 612 and the upper surface of the PR layer. At this time, the light emitting layer 613 may be deposited on the upper surface of the electron transport layer 612 through the first deposition hole (H1). Meanwhile, due to this process, the light emitting layer 613 can also be deposited on the PR layer.

Next, referring to FIG. 10F, a first sub hole transport layer 6141 is deposited to surround the light emitting layer 613 of the first organic light emitting layer 61. More specifically, the first sub hole transport layer 6141 may contact each of the top surface 6131 and the side surface 6132 of the light emitting layer 613 through the first deposition hole H1. At this time, since the first sub hole transport layer 6141 is deposited after the light emitting layer 613 is formed, it can cover the light emitting layer 613 and also contact the top surface of the electron transport layer 612. Meanwhile, the first sub hole transport layer 6141 may be deposited on the light emitting layer 613 using a sputter method to have a thickness of 100 Å or more. Accordingly, the first sub hole transport layer 6141 can protect the light emitting layer 613 of the first organic light emitting layer 61 from being damaged by the etchant used in the subsequent process.

Next, referring to FIG. 10g, the light emitting layer 613 of the first organic light emitting layer 61 and the first sub hole transport layer 6141 surrounding the light emitting layer 613 of the first organic light emitting layer 61 are removed. Perform the third removal process. The third removal process is performed except for the light-emitting layer 613 and the first sub-hole transport layer 6141 of the first organic light-emitting layer 61 formed on the upper surface of the electron transport layer 612 in the first sub-pixel 21. The shield layer (SL) applied on the banks including the first bank 5 and the second bank 9, the second sub-electrode 42, and the third sub-electrode 43 is subjected to a strip process. This can be achieved by lift-off through . Accordingly, in the first sub-pixel 21, only the light-emitting layer 613, whose top surface 6131 and side surface 6132 are protected by the first sub hole transport layer 6141, may remain on the top surface of the electron transport layer 612. . Therefore, the first sub hole transport layer 6141 prevents the etchant used in the subsequent process from contacting the light-emitting layer 613 of the first organic light-emitting layer 61, so that the light-emitting layer ( 613) can be prevented from being damaged.

Next, referring to FIG. 10H, the display device 1 according to the third embodiment of the present application has the electron transport layer of the second sub-pixel 22 by repeatedly performing the processes of FIGS. 10B to 10G. A light-emitting layer 623 of the second organic light-emitting layer 62 is formed on the upper surface, the top surface and sides of which are protected by the first sub-hole transport layer 6241 of the second organic light-emitting layer 62, and the third sub-pixel 23 A light-emitting layer 633 of the third organic light-emitting layer 63 may be formed on the top surface of the electron transport layer, with the top and side surfaces protected by the first sub-hole transport layer 6341 of the third organic light-emitting layer 63.

As a result, the display device 1 according to the third embodiment of the present application has the first sub hole transport layer 6141 of the first organic light-emitting layer 61 protecting the light-emitting layer 613 of the first organic light-emitting layer 61. In this state, an etching process is performed to pattern the light-emitting layer 623 of the second organic light-emitting layer 62 and the light-emitting layer 633 of the third organic light-emitting layer 63, so that the light-emitting layer 613 of the first organic light-emitting layer 61 is formed previously. ) can be prevented from being damaged by the etchant used in the subsequent process.

Likewise, in the display device 1 according to the third embodiment of the present application, the first sub hole transport layer 6241 of the second organic light-emitting layer 62 is subjected to an etching process of the light-emitting layer 633 of the third organic light-emitting layer 63. It is possible to prevent the light emitting layer 623 of the second organic light emitting layer 62 from being damaged by the etchant used. The first sub hole transport layer 6341 of the third organic light-emitting layer 63 can prevent the light-emitting layer 633 of the third organic light-emitting layer 63 from being damaged by the etchant of the strip process used in the third removal process. there is.

Meanwhile, although not shown, in the display device 1 according to the third embodiment of the present application, each of the first sub hole transport layers 6141, 6241, and 6341 protects the light emitting layers 613, 623, and 633, respectively. Since the etching process is carried out in , 633) can be prevented from being damaged. Therefore, the display device 1 according to the third embodiment of the present application can prevent foreign substances including the residual shield layer from remaining in the organic light-emitting layer 6, and thus the luminous efficiency of the organic light-emitting layer 6 is reduced due to the foreign substances. Deterioration can be prevented.

Next, referring to FIGS. 10i and 10j, the display device 1 according to the third embodiment of the present application includes a first sub hole transport layer 6141 surrounding the light emitting layer 613 of the first organic light emitting layer 61, After the first sub hole transport layer 6241 surrounding the light emitting layer 623 of the second organic light emitting layer 62 and the first sub hole transport layer 6341 surrounding the light emitting layer 633 of the third organic light emitting layer 63 are formed, the first sub hole transport layer 6241 is formed. The second sub hole transport layer 6142, the second hole transport layer 615, the hole injection layer 616, the second electrode 7, and the encapsulation layer 8 of the organic light emitting layer 61 are sequentially deposited on the entire surface, The manufacturing process may be partially completed.

Here, the second sub-hole transport layer 6142, the second hole transport layer 615, and the hole injection layer 616 of the first organic light-emitting layer 61 are connected to the first sub-pixel 21, the second sub-pixel 22, And since it is a common layer deposited on the entire surface of the third sub-pixel 23, it can be the second sub hole transport layer, the second hole transport layer, and the hole injection layer of the second organic light-emitting layer 62, and the third organic light-emitting layer ( 63) may be the second sub hole transport layer, the second hole transport layer, and the hole injection layer.

As a result, the first sub hole transport layer 6141 of the first organic light emitting layer 61, the first sub hole transport layer 6241 of the second organic light emitting layer 62, and the first sub hole transport layer of the third organic light emitting layer 63 Each of the transport layers 6341 is inside each of the first organic light-emitting layer 61, the second organic light-emitting layer 62, and the third organic light-emitting layer 63. More specifically, between the electron transport layer 612 and the second sub hole transport layer 6142, it contacts the top and side surfaces of the light emitting layers 613, 623, and 633 of each organic light emitting layer 61, 62, and 63, and the electrons The light emitting layers 613, 623, and 633 can be sealed and protected by contacting the upper surface of the transport layer 612.

Although not shown, the display device 1 according to the third embodiment of the present application has a first sub hole transport layer 6141 of the first to third organic light emitting layers 61, 62, and 63, like the display device of FIG. 8 described above. , 6241, 6341), by providing different thicknesses, micro cavity characteristics can be implemented for each of the first to third sub-pixels 21, 22, and 23.

Meanwhile, the display device 1 according to the first to third embodiments of the present application described above includes electron injection layers 611, 621, 631 between the first electrode 4 and the electron transport layers 612, 622, and 632. Although this arrangement has been described, it is not limited to this and an N-doped electron transport layer may be provided instead of the electron injection layer (611, 621, 631).

FIG. 11 is a schematic cross-sectional view of a display device according to a fourth embodiment of the present application, and FIGS. 12A to 12P are schematic cross-sectional views of a manufacturing process of a display device according to a fourth embodiment of the present application.

Referring to FIGS. 11 to 12P, the display device 1 according to the fourth embodiment of the present application is between the first sub hole transport layer 6141 and the second sub hole transport layer 6142 of the first organic light emitting layer 61. A first lifespan improvement layer (LIL1) disposed in, a second lifespan improvement layer (LIL2) disposed between the first sub hole transport layer 6241 and the second sub hole transport layer of the second organic light emitting layer 62, and a third lifespan improvement layer (LIL2) disposed in The display device 1 according to FIG. 1 described above, except that it further includes a third lifespan improvement layer (LIL3) disposed between the first sub hole transport layer 6341 and the second sub hole transport layer of the organic light emitting layer 63. Same as Accordingly, the same reference numerals are assigned to the same components, and only the different components will be described below. And, in the display device 1 according to the fourth embodiment of the present application, the first lifespan improvement layer (LIL1), the second lifespan improvement layer (LIL2), and the third lifespan improvement layer (LIL3) are It may be a shield layer (SL) used in the manufacturing process of the display device according to the first embodiment, and this shield layer (SL) is not completely removed and remains in the manufacturing process of the display device according to the first embodiment, It may be disposed on the light emitting layer. In addition, the display device 1 according to the fourth embodiment is electrophilic because the shield layer SL used in the manufacturing process of the display device according to the first embodiment includes materials such as F, O, N, etc., which will be described later. It can be provided so that the hole injection property is high and the hole injection property is high.

In the case of the display device according to FIG. 1 described above, a second hole provided on the second sub hole transport layer of each of the first to third organic light emitting layers 61, 62, and 63 is made of a different material from the second sub hole transport layer. By disposing the transport layer 615, it is possible to prevent shortening of the lifespan of the light emitting device by ensuring that holes are well injected into the second sub hole transport layer.

On the other hand, in the case of the display device according to the fourth embodiment of FIG. 11, the first to third organic light emitting layers 61, 62, and 63 each have first sub hole transport layers 6141, 6241, and 6341 and second sub hole transport layers 6141, 6241, and 6341, respectively. By arranging the first lifespan improvement layer (LIL1), the second lifespan improvement layer (LIL2), and the third lifespan improvement layer (LIL3) between the hole transport layers, holes are transported from the second sub hole transport layer to the first sub hole transport layer. In addition to increasing the penetration, the first electrode 4, which is a cathode electrode disposed below the light emitting layer 613, 623, 633, the electron injection layer 611, 621, 631, and the electron transport layer 612, 622, 632), by pulling electrons from at least one of the light emitting layers 613, 623, and 633, the exciton generation efficiency can be increased and the lifespan of the organic light emitting layer 6 can be increased.

More specifically, each of the first to third lifespan improvement layers LIL1, LIL2, and LIL3 may be made of a polymer containing fluorine (F), oxygen (O), and nitrogen (N). When the first to third lifespan improvement layers (LIL1, LIL2, LIL3) contain the atoms described above, electron affinity can be increased by having an Electron Withdrawing Group (EWG). The EWG is a functional group with high electronegativity and has the property of pulling electrons mainly through pi bonds. For example, the EWG may be Halides (-F, -CL), Cyano Groups (-CN), Nitro Group (-NO ₂ ), etc.

In addition, each of the first to third lifespan improvement layers (LIL1, LIL2, LIL3) is made of a polymer containing fluorine (F), oxygen (O), and nitrogen (N), thereby enabling hole injection. can be strengthened. Therefore, the first to third lifespan improvement layers (LIL1, LIL2, LIL3) are the second electrode 7, which is an anode electrode disposed on each of the first to third lifespan improvement layers (LIL1, LIL2, LIL3). , Holes moving from the hole injection layer 616, the second hole transport layer 615, and the second sub hole transport layer 6142 toward the light emitting layer (613, 623, 633) are transferred to the light emitting layer (613, 623, 633). By injecting well, the exciton generation efficiency in the light-emitting layer (613, 623, 633) can be increased, thereby increasing the lifespan of the organic light-emitting layer (6).

Meanwhile, the first to third lifespan improvement layers (LIL1, LIL2, LIL3) may each have a thickness of 1 nm or more and 10 nm or less. If the thickness of each of the first to third lifespan improvement layers (LIL1, LIL2, LIL3) is less than 1 nm, the electron pulling property and hole injection property may be so low that the effect of improving the lifespan of the organic light-emitting layer 6 may not appear. . On the other hand, when the thickness of each of the first to third lifespan improvement layers (LIL1, LIL2, LIL3) exceeds 10 nm, the first to third lifespan improvement layers (LIL1, LIL2, LIL3) are the first sub hole transport layer 6141. , 6241, 6341) and the second sub-hole transport layer, a problem of lowering hole injection into the light-emitting layer 613, 623, 633 may occur. Accordingly, the display device 1 according to the fourth embodiment of the present application has the first to third lifespan improvement layers LIL1, LIL2, and LIL3 each having a thickness of 1 nm to 10 nm, so that the first sub-hole By minimizing the barrier function between the transport layer (6141, 6241, 6341) and the second sub hole transport layer, the electron pulling and hole injection properties are increased to the light emitting layer (613, 623, 633). The lifespan of the organic light-emitting layer 6 can be increased by increasing the exciton generation efficiency.

Referring again to FIG. 11, in the display device 1 according to the fourth embodiment of the present application, the first lifespan improvement layer LIL1 is the first sub hole transport layer 6141 of the first organic light emitting layer 61. ), the second lifespan improvement layer (LIL2) is disposed only on the top surface of the first sub hole transport layer 6241 of the second organic light-emitting layer 62, and the third lifespan improvement layer (LIL3) is It may be disposed only on the top surface of the first sub hole transport layer 6341 of the third organic light emitting layer 63. This is because the first to third organic light emitting layers 61, 62, and 63 of the display device 1 according to the fourth embodiment of the present application are formed through a dry etching process. A detailed description of this will be provided in the manufacturing process of FIGS. 12A to 12P.

Since the first lifespan improvement layer (LIL1) is disposed only on the top surface of the first sub hole transport layer 6141 of the first organic light-emitting layer 61, both ends of the first lifespan improvement layer (LIL1) are connected to the first organic light-emitting layer. It may be provided to coincide with both ends of each of the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, and the first sub hole transport layer 6141 of (61).

Likewise, the second lifespan improvement layer (LIL2) is disposed only on the top surface of the first sub hole transport layer 6241 of the second organic light-emitting layer 62, so that both ends of the second lifespan improvement layer (LIL2) are connected to the second lifespan improvement layer (LIL2). It may be provided to coincide with both ends of the electron injection layer 621, the electron transport layer 622, the light emitting layer 623, and the first sub hole transport layer 6241 of the organic light emitting layer 62, and a third lifespan improvement layer. (LIL3) is disposed only on the top surface of the first sub hole transport layer 6341 of the third organic light-emitting layer 63, so that both ends of the third lifespan improvement layer (LIL3) are exposed to electrons of the third organic light-emitting layer 63. It may be provided to coincide with both ends of each of the injection layer 631, the electron transport layer 632, the light emitting layer 633, and the first sub hole transport layer 6341.

12A to 12P are schematic cross-sectional views of the manufacturing process of a display device according to a fourth embodiment of the present application.

The display device 1 according to the fourth embodiment of the present application includes the first sub hole transport layers 6141, 6241, and 6341 of each of the first to third organic light emitting layers 61, 62, and 63 through the following manufacturing process. By arranging the first lifespan improvement layer (LIL1), the second lifespan improvement layer (LIL2), and the third lifespan improvement layer (LIL3) between the second sub hole transport layers, respectively, electrons to the light emitting layers 613, 623, and 633 Since the attraction and hole injection properties can be increased, the exciton generation efficiency of the light-emitting layers 613, 623, and 633 can be increased, thereby increasing the lifespan of the organic light-emitting layer 6.

In the manufacturing process of FIGS. 2A to 2P described above, the shield layer (SL) was used in the patterning process to form the first to third organic light emitting layers 61, 62, and 63, but in the manufacturing process of FIGS. 12A to 12P, By using a lifespan improvement layer instead of the shield layer SL, the lifespan improvement layer can be disposed between the first sub hole transport layer and the second sub hole transport layer. Here, the lifespan improvement layer may refer to the first to third lifespan improvement layers LIL1, LIL2, and LIL3. Therefore, except for the above differences, FIGS. 12A to 12P are mostly the same as the manufacturing process of FIGS. 2A to 2P described above. Therefore, only the different manufacturing processes will be described below.

FIGS. 12A to 12E are the same except that the first lifespan improvement layer LIL1 is used instead of the shield layer SL of FIGS. 2A to 2E, and detailed description thereof will be omitted.

Next, referring to FIG. 12f, a first removal process of removing the PR layer in the remaining area excluding the first organic light-emitting layer 61 area, and the first lifespan improvement layer in the remaining area excluding the first organic light-emitting layer 61 area. A secondary removal process is performed to remove (LIL1), the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, and the first sub hole transport layer 6141. The first removal process and the second removal process may be performed using at least one of etching gas, developer solution, and stripper solution. The PR layer can be corroded and removed by immersing it in a developer.

In the secondary removal process, the first organic light-emitting layer 61 and the first lifespan improvement layer (LIL1) of the remaining area including the PR layer on the first organic light-emitting layer 61 area are removed using an etching gas or a stripper solution. You can. The secondary removal process removes a larger amount of organic matter containing the first lifespan improvement layer (LIL1) compared to the first removal process by extending the exposure time to the etching gas or stripper solution compared to the first removal process. can do. At this time, the secondary removal process can be performed only until a portion of the first lifespan improvement layer LIL1 remains on the upper surface of the first sub hole transport layer 6141 with a thickness of 1 nm to 10 nm.

Through this process, the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, and the first sub hole of the first organic light-emitting layer 61 are formed only on the top surface 41a of the first sub-electrode 41. The transport layer 6141 and the first lifespan improvement layer (LIL1) remain, and the remaining area includes the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, and the first sub-layer of the first organic light-emitting layer 61. The hole transport layer 6141, the first lifespan improvement layer (LIL1), and the PR layer may be removed. The remaining area includes the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, and the first sub hole transport layer of the first organic light-emitting layer 61 on the upper surface 41a of the first sub-electrode 41. (6141), and an area excluding the patterned portion of the first lifespan improvement layer (LIL1), including the first bank 5, the second sub-pixel 22, the second bank 9, and the third sub-pixel ( 23) may be an area included.

Meanwhile, the first lifespan improvement layer (LIL1) is disposed on the first sub hole transport layer 6141, and the electron injection layer 611, the electron transport layer 612, and the light emitting layer ( 613), and are dry-etched together with the first sub hole transport layer 6141. Therefore, as shown in FIG. 12F, both ends of the first lifespan improvement layer (LIL1) include the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, and the electron injection layer 611 of the first organic light-emitting layer 61. and may be provided to coincide with both ends of each of the first sub hole transport layers 6141.

The manufacturing process of the display device 1 according to the fourth embodiment of the present application is the same exposure process as above after disposing the first sub hole transport layer 6141 and the first lifespan improvement layer LIL1 on the upper surface of the light emitting layer 613. , Since the removal process, that is, the patterning process, is performed, the first sub hole transport layer 6141 and the first lifespan improvement layer (LIL1) can prevent the light emitting layer 613 from being damaged by UV light, etching gas, and stripper solution. .

Next, referring to FIGS. 12G to 12J, the process of FIGS. 12B to 12F described above is repeated to form a portion of the second organic light emitting layer 62 and the second lifespan improvement layer LIL2 in the second sub-pixel 22. can do. Since the manufacturing process of FIGS. 12G to 12J is the same as that of FIGS. 2G to 2J except that the second lifespan improvement layer (LIL2) is used instead of the shield layer (SL), detailed descriptions are omitted. However, in FIG. 12J, it is mentioned in FIG. 12E that the removal process is performed only until a portion of the second lifespan improvement layer (LIL2) remains on the top surface of the first sub hole transport layer 6241 with a thickness of 1 nm to 10 nm. It is the same as what was said.

Therefore, as shown in FIG. 12J, the electron injection layer 621, the electron transport layer 622, the light emitting layer 623, The first sub hole transport layer 6241 and the second lifespan improvement layer LIL2 may remain. In addition, both ends of the second lifespan improvement layer (LIL2) include the electron injection layer 621, the electron transport layer 622, the light emitting layer 623, and the first sub hole transport layer 6241 of the second organic light-emitting layer 62. ) Can be provided to match both ends of each.

The manufacturing process of the display device 1 according to the fourth embodiment of the present application is to place the first sub hole transport layer 6241 and the second lifespan improvement layer LIL2 on the upper surface of the light emitting layer 623, followed by an exposure process and removal. As the process is performed, the first sub hole transport layer 6241 and the second lifespan improvement layer LIL2 can prevent the light emitting layer 623 from being damaged by UV light, etching gas, and stripper solution.

Next, referring to FIGS. 12K to 12N, the above-described processes of FIGS. 12B to 12F are repeated to form a portion of the third organic light-emitting layer 63 and the third lifespan improvement layer LIL3 in the third sub-pixel 23. can do. Since the manufacturing process of FIGS. 12K to 12N is the same as that of FIGS. 2K to 2N except that the third lifespan improvement layer (LIL3) is used instead of the shield layer (SL), detailed descriptions are omitted. However, in FIG. 12K, it is mentioned in FIG. 12E that the removal process is performed only until a portion of the third lifespan improvement layer (LIL3) remains on the top surface of the first sub hole transport layer 6341 with a thickness of 1 nm to 10 nm. It is the same as what was said.

Therefore, as shown in FIG. 12n, the electron injection layer 631, the electron transport layer 632, the light emitting layer 633, The first sub hole transport layer 6341 and the third lifespan improvement layer LIL3 may remain. In addition, both ends of the third lifespan improvement layer (LIL3) include the electron injection layer 631, the electron transport layer 632, the light emitting layer 633, and the first sub hole transport layer 6341 of the third organic light-emitting layer 63. ) Can be provided to match both ends of each.

The manufacturing process of the display device 1 according to the fourth embodiment of the present application is to place the first sub hole transport layer 6341 and the third lifespan improvement layer (LIL3) on the upper surface of the light emitting layer 633, followed by an exposure process and removal. As the process is performed, the first sub hole transport layer 6341 and the third lifespan improvement layer LIL3 can prevent the light emitting layer 633 from being damaged by UV light, etching gas, and stripper solution.

Next, referring to FIGS. 12o and 12p, the electron injection layer 611, the electron transport layer 612 of the first organic light-emitting layer 61 are patterned for each of the first to third sub-pixels 21, 22, and 23, respectively. The light-emitting layer 613, the first sub-hole transport layer 6141, and the first lifespan improvement layer (LIL1), and the electron injection layer 621, the electron transport layer 622, and the light-emitting layer 623 of the second organic light-emitting layer 62. , the first sub hole transport layer 6241, and the second lifespan improvement layer (LIL2), the electron injection layer 631 of the third organic light-emitting layer 63, the electron transport layer 632, the light-emitting layer 633, and the first sub A second sub-hole transport layer 6142, a second hole transport layer 615, and a hole injection layer 616 of the first organic light-emitting layer 61 to cover the hole transport layer 6341 and the third lifespan improvement layer (LIL3), By sequentially depositing the second electrode 7 and the encapsulation layer 8 on the entire surface, the manufacturing process can be partially completed.

Here, the second sub-hole transport layer 6142, the second hole transport layer 615, and the hole injection layer 616 of the first organic light-emitting layer 61 are connected to the first sub-pixel 21, the second sub-pixel 22, And since it is a common layer deposited on the entire surface of the third sub-pixel 23, it can be the second sub hole transport layer, the second hole transport layer, and the hole injection layer of the second organic light-emitting layer 62, and the third organic light-emitting layer ( 63) may be the second sub hole transport layer, the second hole transport layer, and the hole injection layer.

Accordingly, the second sub hole transport layer 6142 deposited on the entire surface of the first to third sub pixels 21, 22, and 23 is formed on the upper surface of each of the first to third lifespan improvement layers LIL1, LIL2, and LIL3. Side, each side of the first sub hole transport layer (6141, 6241, 6341), side of the light emitting layer (613, 623, 633), side of the electron transport layer (612, 622, 632), and electron injection layer (611, 621, 631) can cover the sides.

The display device 1 according to the fourth embodiment of the present application includes the second sub hole transport layer 6142, the second hole transport layer 615, and the hole injection layer 616 of the organic light emitting layer 6. By arranging a common layer that covers all of the sub-pixels 21, 22, and 23, the number of manufacturing processes can be reduced compared to the case of forming a second sub-hole transport layer, a second hole transport layer, and a hole injection layer for each sub-pixel. This can have the effect of reducing the tact time of the display device.

Meanwhile, as shown in FIG. 12p, the electron injection layer 611, the electron transport layer 612, the light emitting layer 613, the first sub hole transport layer 6141, and the first lifespan of the first organic light-emitting layer 61 are improved. The layer (LIL1) includes the electron injection layer 621, the electron transport layer 622, the light emitting layer 623, the first sub hole transport layer 6241, and the second lifespan improvement layer (LIL2) of the second organic light-emitting layer 62, respectively. and may be arranged to be spaced apart from each other. Accordingly, even if an electric field is formed between the first sub-electrode 41 and the second electrode 7, no leakage current is generated toward the second sub-pixel 22, so the second sub-pixel 22 does not emit light. You can. Likewise, even if an electric field is formed between the second sub-electrode 42 and the second electrode 7, no leakage current occurs toward the first sub-pixel 21, so the first sub-pixel 21 may not emit light. there is.

In addition, the electron injection layer 631, the electron transport layer 632, the light emitting layer 633, the first sub hole transport layer 6341, and the third lifespan improvement layer (LIL3) of the third organic light-emitting layer 63 are the second layer. It may be arranged to be spaced apart from each of the electron injection layer 621, the electron transport layer 622, the light emitting layer 623, the first sub hole transport layer 6241, and the second lifespan improvement layer (LIL2) of the organic light emitting layer 62. there is. Accordingly, even if an electric field is formed between the third sub-electrode 43 and the second electrode 7, no leakage current occurs toward the second sub-pixel 22, so the second sub-pixel 22 does not emit light. You can.

As a result, the display device 1 according to the fourth embodiment of the present application includes the first to third organic light emitting layers 61, 62, and 63, each of the electron injection layers 611, 621, and 631, and the electron transport layer 612. 622, 632, the light emitting layer (613, 623, 633), the first sub hole transport layer (6141, 6241, 6341), and the first to third lifespan improvement layers (LIL1, LIL2, LIL3) are provided to be spaced apart from each other. It is possible to prevent color mixing between adjacent sub-pixels that emit light of different colors.

Figure 13 is a graph showing improvement in the lifespan of the organic light emitting layer of the display device according to the fourth embodiment of the present application.

In Figure 13, the horizontal axis represents time, and the vertical axis represents initial luminance converted to 100%. Here, L7 is a graph showing the lifespan of the light-emitting layer when the patterning process is performed in a state in which the electron injection layer, electron transport layer, light-emitting layer, and hole transport layer are sequentially deposited in a vacuum condition without a lifespan improvement layer, and L8 is a graph showing the lifespan of the light-emitting layer in the fourth of the present application. A patterning process is performed with the first sub hole transport layer 6141 and the first lifespan improvement layer (LIL1) of the display device 1 according to the embodiment covering the light emitting layer 613, and the second sub hole transport layer is made of the same material. This is a graph showing the lifespan of the light emitting layer when 6142 covers the first sub hole transport layer 6141. As shown in FIG. 13, it can be estimated that the device lifespan of the light-emitting layer for L7 is about 380 hours, while the device lifespan of the light-emitting layer for L8 is about 440 hours.

As a result, in the display device 1 according to the fourth embodiment of the present application, the patterning process is performed with the first sub hole transport layer 6141 and the first lifespan improvement layer LIL1 covering the light emitting layer 613, The second sub hole transport layer 6142 made of the same material as the first sub hole transport layer 6141 is arranged to cover the first sub hole transport layer 6141, so that the electron injection layer, electron transport layer, and light emitting layer are formed in a vacuum without a lifespan improvement layer. , the device lifespan of the light-emitting layer 613 can be improved compared to the case where the patterning process was performed with the hole transport layers sequentially deposited.

FIG. 14 is a schematic cross-sectional view of a display device according to a fifth embodiment of the present application, and FIGS. 15A to 15P are schematic cross-sectional views of a manufacturing process of a display device according to a fifth embodiment of the present application.

Referring to FIGS. 14 to 15P, the display device 1 according to the fifth embodiment of the present application is between the first sub hole transport layer 6141 and the second sub hole transport layer 6142 of the first organic light emitting layer 61. It further includes a first lifespan improvement layer (LIL1) disposed in and a second lifespan improvement layer (LIL2) disposed between the first sub hole transport layer 6241 and the second sub hole transport layer of the second organic light emitting layer 62. It is the same as the display device 1 according to FIG. 3 described above except for this. Accordingly, the same reference numerals are assigned to the same components, and only the different components will be described below. And, in the display device 1 according to the fifth embodiment of the present application, the first lifespan improvement layer LIL1 and the second lifespan improvement layer LIL2 are formed through the manufacturing process of the display device according to the third embodiment. It may be a shield layer (SL) used in , and this shield layer (SL) is not completely removed in the manufacturing process of the display device according to the third embodiment and remains, so that it may be disposed on the light emitting layer. In addition, the display device 1 according to the fifth embodiment is electrophilic because the shield layer SL used in the manufacturing process of the display device according to the third embodiment includes materials such as F, O, N, etc., which will be described later. It can be provided so that the hole injection property is high and the hole injection property is high.

In the case of the display device according to FIG. 3 described above, the electron injection layers 611, 621, 631 and the electron transport layers 612, 622, and 632 of each of the first to third organic light emitting layers 61, 62, and 63 are connected to each other. By forming the electron injection layer and the electron transport layer for each sub-pixel 21, 22, and 23, the number of manufacturing processes can be reduced, so not only can the tact time of the completed display device be reduced, but the first By disposing a second hole transport layer 615 made of a different material from the second sub hole transport layer on each of the second sub hole transport layers of the to third organic light emitting layers 61, 62, and 63, the second sub hole transport layer 615 is formed of a different material from the second sub hole transport layer. By ensuring that holes are well injected into the transport layer, shortening the lifespan of the light emitting device can be prevented.

On the other hand, in the case of the display device according to the fifth embodiment of FIG. 14, between the first sub hole transport layers 6141 and 6241 and the second sub hole transport layers of the first and second organic light emitting layers 61 and 62, respectively. By arranging the first lifespan improvement layer (LIL1) and the second lifespan improvement layer (LIL2) respectively, not only can the hole injection property be improved from the second sub hole transport layer to the first sub hole transport layer, but also the light emitting layer (613, 623) By pulling electrons from at least one of the first electrode 4, the electron injection layer 611, 621, 631, and the electron transport layer 612, 622, 632 disposed on the lower side of the light emitting layer 613, 623, 633 ), the lifespan of the organic light-emitting layer 6 can be increased by increasing the exciton generation efficiency. This effect is the same as that of the display device according to the fourth embodiment described above.

However, unlike the display device according to the fourth embodiment, the display device 1 according to the fifth embodiment of the present application has a space between the first sub hole transport layer 6341 and the second sub hole transport layer of the third organic light emitting layer 63. The third lifespan improvement layer (LIL3) is not disposed.

In addition, in the display device 1 according to the fifth embodiment of the present application, unlike the display device according to the fourth embodiment, the first lifespan improvement layer LIL1 is the first sub hole transport layer ( 6141), and the second lifespan improvement layer LIL2 is disposed on the top and side surfaces of the first sub-hole transport layer 6241 of the second organic light-emitting layer 62.

The reason why the display device according to the fifth embodiment is different from the display device according to the fourth embodiment is that the display device according to the fourth embodiment uses a dry-etching process to While the light emitting layers 61, 62, and 63 are formed, the display device according to the fifth embodiment uses a lift-off process to form the first to third organic light emitting layers 61, 62, and 63. Because.

Due to this difference in process, the display device 1 according to the fifth embodiment of the present application improves the lifespan between the first sub hole transport layer 6341 and the second sub hole transport layer of the third organic light emitting layer 63. The layer (LIL3) is not disposed, the first lifespan improvement layer (LIL1) is disposed on the top and side surfaces of the first sub hole transport layer 6141 of the first organic light-emitting layer 61, and the second lifespan improvement layer (LIL2) The second organic light emitting layer 62 may be disposed on the top and side surfaces of the first sub hole transport layer 6241.

Hereinafter, the display device 1 according to the fifth embodiment of the present application shown in FIG. 14 will be combined with the manufacturing process of the display device 1 according to the fifth embodiment of the present application shown in FIGS. 15A to 15P. The above differences will be explained in detail.

First, referring to FIGS. 15A to 15B, the first electrode 4, the first bank 5, and the second bank 9 are formed on the substrate 2 and the circuit element layer 3. In, after sequentially applying the electron injection layer 611, the electron transport layer 612, the shield layer (SL), and the PR layer of the first organic light-emitting layer 61, the first deposition hole (H1, shown in Figure 15c) A mask (M, shown in FIG. 15B) is placed in the area where the mask is to be formed, and then the remaining portion is exposed. Accordingly, the characteristics of the remaining areas of the PR layer, excluding the area where the first deposition hole H1 will be formed, may be changed so that they are not etched by the developer.

Since the electron injection layer 611 and the electron transport layer 612 of the first organic light-emitting layer 61 are entirely deposited as a common layer, the electron injection layer 621 and the electron transport layer 622 of the second organic light-emitting layer 62, It may be the electron injection layer 631 and the electron transport layer 632 of the third organic light-emitting layer 63.

The first deposition hole (H1) is a hole for forming the light-emitting layer 613, the first sub-hole transport layer 6141, and the first lifespan improvement layer (LIL1) of the first organic light-emitting layer 61, and is ultimately It may be the top surface of the electron transport layer 612. The PR layer may be a photoresist layer. The light-emitting layer 613 may be a red light-emitting layer that emits red (R) light when an electric field is generated.

Next, referring to FIG. 15C, a first removal process is performed in which the PR layer located in the area where the first deposition hole H1 is to be formed is removed using a developer. The PR layer removed by the developer can be corroded and removed by being immersed in the developer.

Next, referring to FIG. 15D, a secondary removal process is performed in which the shield layer SL located in the area where the first deposition hole H1 is to be formed is removed using a developer. At this time, in the second removal process, the time for immersion in the developer is increased compared to the first removal process, thereby increasing the volume of the shield layer (SL) removed compared to the first removal process, resulting in a so-called undercut. UC) area can be formed. Accordingly, the width of the shield layer SL removed by the second removal process may be wider than the width of the PR layer removed by the first removal process.

Next, referring to FIG. 15E, the light emitting layer 613 of the first organic light emitting layer 61 is formed on the electron transport layer 612 disposed in the first deposition hole H1. For example, the light-emitting layer 613 of the first organic light-emitting layer 61 can be formed by supplying and depositing organic materials in various ways from outside the PR layer toward the electron transport layer 612 and the upper surface of the PR layer. At this time, the light emitting layer 613 may be deposited on the upper surface of the electron transport layer 612 through the first deposition hole (H1). Meanwhile, due to this process, the light emitting layer 613 can also be deposited on the PR layer.

Next, referring to FIG. 15F, a first sub hole transport layer 6141 is deposited to surround the light emitting layer 613 of the first organic light emitting layer 61. More specifically, the first sub hole transport layer 6141 may contact each of the top surface 6131 and the side surface 6132 of the light emitting layer 613 through the first deposition hole H1. At this time, since the first sub hole transport layer 6141 is deposited after the light emitting layer 613 is formed, it can cover the light emitting layer 613 and also contact the top surface of the electron transport layer 612. Meanwhile, the first sub hole transport layer 6141 may be deposited on the light emitting layer 613 using a sputter method to have a thickness of 100 Å or more. Therefore, the first sub hole transport layer 6141 can protect the light emitting layer 613 of the first organic light emitting layer 61 from being damaged by the etchant used in the subsequent process.

Next, referring to FIG. 15g, the rest except the light-emitting layer 613 of the first organic light-emitting layer 61 and the first sub-hole transport layer 6141 surrounding the light-emitting layer 613 of the first organic light-emitting layer 61 are removed. Perform the third removal process. The third removal process is performed except for the light-emitting layer 613 and the first sub-hole transport layer 6141 of the first organic light-emitting layer 61 formed on the upper surface of the electron transport layer 612 in the first sub-pixel 21. The shield layer (SL) applied on the banks including the first bank 5 and the second bank 9, the second sub-electrode 42, and the third sub-electrode 43 is subjected to a strip process. This can be achieved by lift-off through . Accordingly, in the first sub-pixel 21, only the light-emitting layer 613, whose top surface 6131 and side surface 6132 are protected by the first sub hole transport layer 6141, may remain on the top surface of the electron transport layer 612. . Therefore, the first sub hole transport layer 6141 prevents the etchant used in the subsequent process from contacting the light-emitting layer 613 of the first organic light-emitting layer 61, so that the light-emitting layer ( 613) can be prevented from being damaged.

Next, referring to FIG. 15H, after sequentially applying the first lifespan improvement layer (LIL1) and the PR layer, the mask (M) is placed where the second deposition hole (H2, shown in FIG. 15I) will be formed. The remaining part is exposed. Accordingly, the characteristics of the remaining areas of the PR layer, excluding the area where the second deposition hole H2 will be formed, may be changed so that they are not etched by the developer.

The second deposition hole (H2) is a hole for forming the light emitting layer 623 and the first sub hole transport layer 6241 of the second organic light emitting layer 62, and will ultimately become the upper surface of the electron transport layer 612. You can. The light-emitting layer 623 may be a green light-emitting layer that emits green (G) light when an electric field is generated.

Next, referring to FIG. 15I, a first removal process is performed to remove the PR layer located in the area where the second deposition hole H2 is to be formed using a developer. The PR layer removed by the developer can be corroded and removed by being immersed in the developer.

Next, referring to FIG. 15J, a secondary removal process is performed in which the first lifespan improvement layer LIL1 located in the area where the first deposition hole H1 is to be formed is removed using a developer. At this time, in the second removal process, the time for immersion in the developer is increased compared to the first removal process, thereby increasing the volume of the first lifespan improvement layer (LIL1) removed compared to the first removal process, resulting in undercut (UC) ) area can be formed. Accordingly, the width of the first lifespan improvement layer LIL1 removed by the second removal process may be wider than the width of the PR layer removed by the first removal process.

Next, referring to FIG. 15K, the light emitting layer 623 of the second organic light emitting layer 62 is formed on the electron transport layer 612 disposed in the second deposition hole H2. For example, the light-emitting layer 623 of the second organic light-emitting layer 62 can be formed by supplying and depositing organic materials in various ways from outside the PR layer toward the electron transport layer 612 and the upper surface of the PR layer. At this time, the light emitting layer 623 may be deposited on the upper surface of the electron transport layer 612 through the second deposition hole (H2). Meanwhile, due to this process, the light emitting layer 623 can also be deposited on the PR layer.

Next, referring to FIG. 15L, a first sub hole transport layer 6141 is deposited to surround the light emitting layer 623 of the second organic light emitting layer 62. More specifically, the first sub hole transport layer 6141 may contact each of the top surface 6231 and the side surface 6232 of the light emitting layer 623 through the second deposition hole H2. At this time, since the first sub hole transport layer 6141 is deposited after the light emitting layer 623 is formed, it can cover the light emitting layer 623 and also contact the top surface of the electron transport layer 612. Meanwhile, the first sub hole transport layer 6141 may be deposited on the light emitting layer 623 using a sputter method to have a thickness of 100 Å or more. Accordingly, the first sub hole transport layer 6141 can protect the light emitting layer 623 of the second organic light emitting layer 62 from being damaged by the etchant used in the subsequent process.

Next, referring to FIG. 15M, a third removal process is performed to remove the light-emitting layer 623 of the second organic light-emitting layer 62 and the first sub-hole transport layer 6241 surrounding the light-emitting layer 613. . The third removal process is performed except for the light emitting layer 623 and the first sub hole transport layer 6241 of the second organic light emitting layer 62 formed on the upper surface of the electron transport layer 612 in the second sub pixel 22. 1 The first lifespan improvement layer LIL1 applied on the sub-pixel 21, the banks including the first bank 5 and the second bank 9, and the third sub-electrode 43 is formed into a strip ( This can be achieved by lift-off through a strip process. At this time, in the first sub-pixel 21, only a portion of the first lifespan improvement layer LIL1 arranged to cover the top and side surfaces of the first sub hole transport layer 6141 of the first organic light-emitting layer 61 remains. A third removal process may be performed.

Accordingly, in the second sub-pixel 22, only the light-emitting layer 623, whose top surface 6231 and side surface 6232 are protected by the first sub hole transport layer 6241, may remain on the top surface of the electron transport layer 612. Therefore, the first sub hole transport layer 6241 prevents the etchant used in the subsequent process from contacting the light-emitting layer 623 of the second organic light-emitting layer 62, so that the light-emitting layer ( 623) can be prevented from being damaged.

Meanwhile, through the third removal process, the first lifespan improvement layer LIL1 may be disposed to cover the top and side surfaces of the first sub hole transport layer 6141, which covers the top and side surfaces of the light emitting layer 613.

As a result, the manufacturing process of the display device according to the fifth embodiment of the present application is to form the first lifespan improvement layer LIL1 when forming a part of the second organic light emitting layer 62 in the second sub-pixel 22. It can be formed in 1 sub-pixel 21.

Next, referring to FIG. 15N, by repeating the processes of FIGS. 15H to 15M described above, the first sub of the third organic light-emitting layer 63 is formed on the upper surface of the electron transport layer 612 of the third sub-pixel 23. A light-emitting layer 633 of the third organic light-emitting layer 63 is formed whose top and side surfaces are protected by a hole transport layer 6341, and a second organic light-emitting layer is formed on the top surface of the electron transport layer 612 of the second sub-pixel 22. A light emitting layer 623 whose top and side surfaces are protected by the first sub hole transport layer 6241 of (62) and a second lifespan improvement layer (LIL2) to cover the top and side surfaces of the first sub hole transport layer 6241. can be placed.

As a result, the manufacturing process of the display device according to the fifth embodiment of the present application is such that the first sub hole transport layer 6141 and the first lifespan improvement layer LIL1 of the first organic light emitting layer 61 are formed in the first organic light emitting layer 61. ), a lift-off process is performed to form the light-emitting layer 623 of the second organic light-emitting layer 62 and the light-emitting layer 633 of the third organic light-emitting layer 63 in a state in which the top and side surfaces of the light-emitting layer 613 are double protected. Therefore, it is possible to prevent the light emitting layer 613 of the first organic light emitting layer 61 formed previously from being damaged by the etchant used in the subsequent process.

Likewise, the manufacturing process of the display device according to the fifth embodiment of the present application is such that the first sub hole transport layer 6241 and the second lifespan improvement layer (LIL2) of the second organic light emitting layer 62 are formed by forming the second organic light emitting layer 62. The light emitting layer 623 of the second organic light emitting layer 62 is removed from the etchant used in the lift-off process when forming the light emitting layer 633 of the third organic light emitting layer 63 while the top and side surfaces of the light emitting layer 623 are double protected. This can prevent damage.

Meanwhile, in the third sub-pixel 23, the first sub hole transport layer 6341 of the third organic light-emitting layer 63 is lifted off while protecting the top and side surfaces of the light-emitting layer 633 of the third organic light-emitting layer 63. Since the process is performed, it is possible to prevent the light emitting layer 633 of the third organic light emitting layer 63 from being damaged by the etchant used in the lift-off process.

As seen above, the manufacturing process of the display device according to the fifth embodiment of the present application involves forming a part of the second organic light-emitting layer 62 in the second sub-pixel 22. 1 The lifespan improvement layer LIL1 is formed, and when a part of the third organic light-emitting layer 63 is formed in the third sub-pixel 23, the second lifespan improvement layer LIL2 is formed in the second sub-pixel 22. Therefore, the third lifespan improvement layer cannot be formed in the third sub-pixel 23. Accordingly, in the manufacturing process of the display device according to the fifth embodiment of the present application, the remaining common layers can be formed in the state as shown in FIG. 15N.

Meanwhile, although not shown, in the manufacturing process of the display device according to the fifth embodiment of the present application, the first sub hole transport layer 6141 and the first lifespan improvement layer (LIL1) protect the light emitting layer 613, and the first sub hole transport layer 6141 protects the light emitting layer 613. Since the lift-off process is performed while the hole transport layer 6241 and the second lifespan improvement layer (LIL2) protect the light-emitting layer 623 and the first sub-hole transport layer 6341 protects the light-emitting layer 633, the lift-off process is performed. Even if an additional rinsing process is performed to more reliably remove residual substances on the structure after the process, each of the light emitting layers 613, 623, and 633 can be prevented from being damaged by the cleaning solution used in the rinsing process. .

Next, referring to FIGS. 15o and 15p, the second sub hole transport layer 6142, the second hole transport layer 615, the hole injection layer 616, the second electrode 7, of the first organic light emitting layer 61. and the encapsulation layer 8 are sequentially deposited on the entire surface, thereby partially completing the manufacturing process.

Here, the second sub-hole transport layer 6142, the second hole transport layer 615, and the hole injection layer 616 of the first organic light-emitting layer 61 are connected to the first sub-pixel 21, the second sub-pixel 22, And since it is a common layer deposited on the entire surface over the third sub-pixel 23, it can be the second sub hole transport layer, the second hole transport layer, and the hole injection layer of the second organic light-emitting layer 62, and the third organic light-emitting layer ( 63) may be the second sub hole transport layer, the second hole transport layer, and the hole injection layer.

As a result, the first sub hole transport layer 6141 and the first lifespan improvement layer (LIL1) of the first organic light emitting layer 61, and the first sub hole transport layer 6241 and the second lifespan of the second organic light emitting layer 62 are improved. The first sub-hole transport layer 6341 of the layer LIL2 and the third organic light-emitting layer 63 are each of the first organic light-emitting layer 61, the second organic light-emitting layer 62, and the third organic light-emitting layer 63. ) inside each. More specifically, between the electron transport layer 612 and the second sub hole transport layer 6142, it contacts the top and side surfaces of the light emitting layers 613, 623, and 633 of each organic light emitting layer 61, 62, and 63, and the electrons The light emitting layers 613, 623, and 633 can be sealed and protected by contacting the upper surface of the transport layer 612.

Meanwhile, the first lifespan improvement layer (LIL1) pulls electrons to the light-emitting layer 613 of the first organic light-emitting layer 61 and simultaneously enhances hole injection to increase the exciton generation efficiency of the light-emitting layer 613. The service life is increased by reducing voltage reduction, and the second lifespan improvement layer (LIL2) pulls electrons to the light-emitting layer 623 of the second organic light-emitting layer 62 and at the same time strengthens hole injection to reduce exciton ( As described above, the service life is increased by reducing the driving voltage reduction by increasing the exciton generation efficiency.

However, in the display device 1 according to the fifth embodiment of the present application, the first lifespan improvement layer LIL1 is disposed on the top and side surfaces of the light-emitting layer 613, so that electrons are pulled and holes are drawn toward the side of the light-emitting layer 613. Injection may be strengthened, but since the first electrode 4 and the second electrode 7 are disposed above and below the light emitting layer 613, electron pulling and hole injection can be mainly performed in the upward and downward direction, which is the direction of electric field formation. This can be equally applied to the second lifespan improvement layer LIL2 disposed in the second sub-pixel 22.

In summary, the display device 1 according to the fifth embodiment of the present application does not have a third lifespan improvement layer formed in the third sub-pixel 23 due to a manufacturing process different from that of the display device according to the fourth embodiment, A first lifespan improvement layer (LIL1) may be formed in the first sub-pixel 21, and a second lifespan improvement layer (LIL2) may be formed in the second sub-pixel 22. And, unlike the display device according to the fourth embodiment, the first lifespan improvement layer LIL1 of the display device 1 according to the fifth embodiment may cover both the top and side surfaces of the first sub hole transport layer 6141. Since the second lifespan improvement layer (LIL2) can cover both the top and side surfaces of the first sub hole transport layer 6241, the top and side surfaces of the light emitting layer 613 of the first organic light emitting layer 61 and the second organic light emitting layer 61 Since the top and side surfaces of the light emitting layer 623 of the light emitting layer 62 can be double protected, the light emitting layers 613 and 623 can be more safely protected from the etchant compared to the fourth embodiment.

In this specification, the first lifespan improvement layer (LIL1), the second lifespan improvement layer (LIL2), and the third lifespan improvement layer (LIL3) are the first sub hole transport layers (6141, 6241, 6341) and the first lifespan improvement layer (LIL3). Although it is described as being disposed between the 2 sub hole transport layers 6142, it is not necessarily limited to this and the first lifespan improvement layer (LIL1), the second lifespan improvement layer (LIL2), and the third lifespan improvement layer (LIL3) If it does not contact the light emitting layer (613, 623, 633) between the light emitting layer (613, 623, 633) and the second electrode (7), it may be placed in another position. For example, the first lifespan improvement layer (LIL1), the second lifespan improvement layer (LIL2), and the third lifespan improvement layer (LIL3) are between the first hole transport layer and the second hole transport layer 615, and the second lifespan improvement layer (LIL2). It may be installed either between the hole transport layer 615 and the hole injection layer 616, or between the hole injection layer 616 and the second electrode 7. As another example, the first lifespan improvement layer (LIL1), the second lifespan improvement layer (LIL2), and the third lifespan improvement layer (LIL3) include a first hole transport layer and a second hole transport layer as one single layer. It may be disposed on the upper or lower side of the hole transport layer.

16A to 16C relate to a display device according to a sixth embodiment of the present application, which relates to a head mounted display (HMD) device. FIG. 16A is a schematic perspective view, FIG. 16B is a schematic plan view of a VR (Virtual Reality) structure, and FIG. 16C is a schematic cross-sectional view of an AR (Augmented Reality) structure.

As can be seen in FIG. 16A, the head-mounted display device according to the present application includes a storage case 10 and a head-mounted band 12.

The storage case 10 stores components such as a display device, a lens array, and an eyepiece lens therein.

The head mounting band 12 is fixed to the storage case 10. The head mounting band 12 is illustrated as being formed to surround the upper surface and both sides of the user's head, but is not limited thereto. The head mounting band 12 is used to secure the head mounted display to the user's head, and can be replaced with a structure in the form of a glasses frame or a helmet.

As can be seen in FIG. 16b, the head-mounted display device 1 with a VR (Virtual Reality) structure according to the present application includes a display device 2a for the left eye, a display device 2b for the right eye, a lens array 11, and a display device 2 for the left eye. It may include an eyepiece lens (20a) and a right eyepiece lens (20b).

The display device 2a for the left eye and the display device 2b for the right eye, the lens array 11, and the left eyepiece 20a and the right eyepiece 20b are stored in the storage case 10 described above. .

The display device 2a for the left eye and the display device 2b for the right eye can display the same image, and in this case, the user can watch the 2D image. Alternatively, the display device 2a for the left eye can display the left eye image and the display device 2b for the right eye can display the right eye image. In this case, the user can view a three-dimensional image. Each of the left eye display device 2a and the right eye display device 2b may be a display device according to the above-described FIGS. 1 to 14 . For example, the display device 2a for the left eye and the display device 2b for the right eye may each be an organic light emitting display device.

Each of the left-eye display device 2a and the right-eye display device 2b includes a plurality of sub-pixels, a circuit element layer 3, a first electrode 4, a first bank 5, an organic light-emitting layer 6, It may include a second electrode 7, an encapsulation layer 8, and a second bank 9, and various images can be displayed by combining the colors of light emitted from each sub-pixel in various ways.

The lens array 11 may be provided between the left eyepiece lens 20a and the left eye display device 2a while being spaced apart from each of the left eyepiece lens 20a and the left eye display device 2a. That is, the lens array 11 may be located in front of the left-eye eyepiece 20a and behind the left-eye display device 2a. In addition, the lens array 11 may be provided between the right eyepiece 20b and the right eye display device 2b while being spaced apart from each of the right eyepiece 20b and the right eye display device 2b. there is. That is, the lens array 11 may be located in front of the right eyepiece 20b and behind the right eye display device 2b.

The lens array 11 may be a micro lens array. The lens array 11 can be replaced with a pin hole array. Due to the lens array 11, the image displayed on the left-eye display device 2a or the right-eye display device 2b may be enlarged and visible to the user.

The user's left eye (LE) may be located in the left eyepiece lens 20a, and the user's right eye (RE) may be located in the right eyepiece lens 20b.

As can be seen in FIG. 16C, the head-mounted display device with an AR (Augmented Reality) structure according to the present invention includes a left-eye display device (2a), a lens array (11), a left-eye eyepiece (20a), and a transmission reflector (13). , and a transmission window 14. In Figure 16c, only the left inner configuration is shown for convenience, and the right inner configuration is also the same as the left inner configuration.

The left-eye display device 2a, lens array 11, left eyepiece 20a, transmission reflector 13, and transmission window 14 are stored in the storage case 10 described above.

The left-eye display device 2a may be disposed on one side, for example, on the upper side of the transmission reflection portion 13 without blocking the transmission window 14. Accordingly, the left-eye display device 2a can provide an image to the transmission reflector 13 without blocking the external background seen through the transmission window 14.

The display device 2a for the left eye may be made of the electroluminescence display device according to the above-described FIGS. 1 to 14. At this time, the upper portion corresponding to the surface on which the image is displayed in FIGS. 1 to 14, for example, the encapsulation layer 8 or the color filter layer (not shown), faces the transmission and reflection portion 13.

The lens array 11 may be provided between the left eyepiece lens 20a and the transmission reflector 13.

The user's left eye is located in the left eyepiece 20a.

The transmission reflector 13 is disposed between the lens array 11 and the transmission window 14. The transmission reflection part 13 may include a reflection surface 13a that transmits part of the light and reflects another part of the light. The reflective surface 13a is formed so that the image displayed on the left-eye display device 2a progresses to the lens array 11. Accordingly, the user can see both the external background and the image displayed by the left eye display device 2a through the transparent window 14. In other words, since the user can view the real background and the virtual image as one image by overlapping them, Augmented Reality (AR) can be implemented.

The transmission window 14 is disposed in front of the transmission reflection portion 13.

The present application described above is not limited to the above-described embodiments and the accompanying drawings, and it is common in the technical field to which this application belongs that various substitutions, modifications, and changes are possible without departing from the technical spirit of the present application. It will be clear to those who have the knowledge of. Therefore, the scope of the present application is indicated by the claims described later, and the meaning and scope of the claims and all changes or modified forms derived from the equivalent concept should be interpreted as being included in the scope of the present application.

1: display device
2: Substrate 3: Circuit element layer
4: first electrode 5: bank
6: organic light emitting layer 7: second electrode
8: Encapsulation layer 9: Second bank
10: Storage case 11: Lens array
12: Head mounting band

Claims (22)

a substrate having a first sub-pixel and a second sub-pixel adjacent to the first sub-pixel;
a first electrode provided on the substrate and including a first sub-electrode provided in the first sub-pixel and a second sub-electrode provided in the second sub-pixel;
an organic light-emitting layer including a first organic light-emitting layer disposed on the first sub-electrode and a second organic light-emitting layer disposed on the second sub-electrode;
a second electrode disposed on the organic light-emitting layer; and
a first bank provided between the first sub-electrode and the second sub-electrode to distinguish the first sub-pixel and the second sub-pixel;
The first organic light-emitting layer includes a light-emitting layer and a first hole transport layer disposed on the light-emitting layer,
The first hole transport layer of the first organic light-emitting layer includes a first sub-hole transport layer and a second sub-hole transport layer,
A first sub hole transport layer of the first hole transport layer of the first organic light emitting layer covers the light emitting layer between the light emitting layer and the second sub hole transport layer,
The second organic light-emitting layer includes a light-emitting layer and a first hole transport layer disposed on the light-emitting layer,
The first hole transport layer of the second organic light-emitting layer includes a first sub-hole transport layer and a second sub-hole transport layer,
The second sub hole transport layer of the first organic light emitting layer is connected to the second sub hole transport layer of the second organic light emitting layer. According to claim 1,
The first organic light-emitting layer includes an electron injection layer and an electron transport layer disposed below the light-emitting layer, and a second hole transport layer and a hole injection layer disposed above the second sub-hole transport layer,
Both ends of the electron injection layer, the electron transport layer, the light emitting layer, and the first sub hole transport layer of the first organic light emitting layer coincide with each other. According to claim 2,
The second organic light-emitting layer includes an electron injection layer, an electron transport layer, a first hole transport layer including the light-emitting layer, the first sub-hole transport layer, and the second sub-hole transport layer, a second hole transport layer, and a hole injection layer,
The electron injection layer, the electron transport layer, the light-emitting layer, and the first sub-hole transport layer of the first organic light-emitting layer are the electron injection layer, the electron transport layer, the light-emitting layer, and the first sub-hole transport layer of the second organic light-emitting layer. A display device spaced apart from the transport layer. According to claim 2,
The second organic light-emitting layer includes an electron injection layer, an electron transport layer, a first hole transport layer including the light-emitting layer, the first sub-hole transport layer, and the second sub-hole transport layer, a second hole transport layer, and a hole injection layer,
The second hole transport layer and the hole injection layer of the first organic light-emitting layer are connected to the second hole transport layer and the hole injection layer of the second organic light-emitting layer. According to claim 3,
The substrate has a third sub-pixel adjacent to one side of the second sub-pixel,
The first electrode is provided on the substrate and includes a third sub-electrode provided in the third sub-pixel,
The organic light-emitting layer includes a third organic light-emitting layer disposed on the third sub-electrode,
The third organic light-emitting layer includes an electron injection layer, an electron transport layer, a light-emitting layer, a first hole transport layer including a first sub-hole transport layer and a second sub-hole transport layer, a second hole transport layer, and a hole injection layer,
A display device wherein the first sub hole transport layer of the third organic emission layer covers the emission layer of the third organic emission layer between the emission layer of the third organic emission layer and the second sub hole transport layer of the third organic emission layer. According to claim 1,
The first organic light-emitting layer includes an electron injection layer and an electron transport layer disposed below the light-emitting layer, and a second hole transport layer and a hole injection layer disposed above the second sub-hole transport layer,
The second organic light-emitting layer includes an electron injection layer, an electron transport layer, a first hole transport layer including the light-emitting layer, the first sub-hole transport layer, and the second sub-hole transport layer, a second hole transport layer, and a hole injection layer,
The electron injection layer, the electron transport layer, the second hole transport layer, and the hole injection layer of the first organic light-emitting layer include the electron injection layer, the electron transport layer, the second hole transport layer, and the A display device connected to each hole injection layer. According to claim 6,
The first sub hole transport layer of the first organic light emitting layer covers the top and side surfaces of the light emitting layer of the first organic light emitting layer and is in contact with the electron transport layer of the first organic light emitting layer. According to claim 6,
The display device wherein the light emitting layer and the first sub hole transport layer of the first organic light emitting layer are spaced apart from each other of the light emitting layer and the first sub hole transport layer of the second organic light emitting layer. According to claim 5,
The first sub hole transport layer of the first organic emission layer, the first sub hole transport layer of the second organic emission layer, and the first sub hole transport layer of the third organic emission layer are each provided with different thicknesses. According to claim 5,
a first lifespan improvement layer disposed between the first sub hole transport layer and the second sub hole transport layer of the first organic light emitting layer;
a second lifespan improvement layer disposed between the first sub hole transport layer and the second sub hole transport layer of the second organic light emitting layer; and
Comprising a third lifespan improvement layer disposed between the first sub hole transport layer and the second sub hole transport layer of the third organic light emitting layer,
The first lifespan improvement layer enhances electron pulling and hole injection into the light-emitting layer of the first organic light-emitting layer,
The second lifespan improvement layer enhances electron pulling and hole injection into the light emitting layer of the second organic light emitting layer,
The third lifespan improvement layer enhances electron pulling and hole injection into the light emitting layer of the third organic light emitting layer,
Each of the first lifespan improvement layer, the second lifespan improvement layer, and the third lifespan improvement layer is formed of a polymer containing fluorine (F), oxygen (O), and nitrogen (N). According to claim 10,
The first lifespan improvement layer is disposed only on the upper surface of the first sub hole transport layer of the first organic light-emitting layer,
The second lifespan improvement layer is disposed only on the upper surface of the first sub hole transport layer of the second organic light emitting layer,
The third lifespan improvement layer is disposed only on the top surface of the first sub hole transport layer of the third organic light emitting layer. According to claim 10,
The first lifespan improvement layer, the second lifespan improvement layer, and the third lifespan improvement layer are polymers containing F, O, and N. According to claim 10,
The display device wherein each of the first lifespan improvement layer, the second lifespan improvement layer, and the third lifespan improvement layer has a thickness of 1 nm to 10 nm. According to claim 6,
a first lifespan improvement layer disposed between the first sub hole transport layer and the second sub hole transport layer of the first organic light emitting layer; and
Comprising a second lifespan improvement layer disposed between the first sub hole transport layer and the second sub hole transport layer of the second organic light emitting layer,
The first lifespan improvement layer enhances electron pulling and hole injection into the light-emitting layer of the first organic light-emitting layer,
The second lifespan improvement layer enhances electron pulling and hole injection into the light-emitting layer of the second organic light-emitting layer,
Each of the first lifespan improvement layer and the second lifespan improvement layer is formed of a polymer containing fluorine (F), oxygen (O), and nitrogen (N). According to claim 14,
The first lifespan improvement layer is disposed on the top and side surfaces of the first sub hole transport layer of the first organic light-emitting layer,
The second lifespan improvement layer is disposed on the top and side surfaces of the first sub hole transport layer of the second organic light emitting layer. The method according to any one of claims 1 to 15,
A display device further comprising a lens array spaced apart from the substrate, and a storage case for storing the substrate and the lens array. The method according to any one of claims 1 to 15,
The first electrode is a cathode electrode, and the second electrode is an anode electrode,
The first electrode is connected to the source electrode or drain electrode of the transistor. The method according to any one of claims 1 to 15,
The display device wherein the first sub hole transport layer of the first organic light emitting layer and the second sub hole transport layer of the first organic light emitting layer are made of the same material. According to claim 2 or 6,
The display device wherein the second sub hole transport layer of the first organic emission layer and the second hole transport layer of the first organic emission layer are made of different materials. The method according to any one of claims 1 to 8,
The difference between the LUMO energy level of the first sub hole transport layer of the first organic emission layer and the LUMO energy level of the second sub hole transport layer of the first organic emission layer is 0.2 eV or more and 0.5 eV or less,
The display device wherein the difference between the HOMO energy level of the first sub hole transport layer of the first organic emission layer and the HOMO energy level of the second sub hole transport layer of the first organic emission layer is 0.2 eV or more and 0.5 eV or less. According to claim 1,
A display device wherein the ratio of oxygen contained in the first sub hole transport layer and the second sub hole transport layer is 3% or more and 16% or less. According to claim 10,
The first lifespan improvement layer, the second lifespan improvement layer, and the third lifespan improvement layer are arranged to be spaced apart from each other.

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