KR20140013515A - Organic light emitting display apparatus and the manufacturing method thereof - Google Patents

Abstract

Disclosed are an organic light emitting display device and a method of manufacturing the same, which can effectively block moisture penetration into an organic light emitting device. The disclosed organic light emitting diode display has an active region divided into an active first region in which an organic light emitting diode is disposed and an active second region adjacent to a sealant region, and a structure in which a pixel definition layer is removed between the active first region and the active second region. Have According to this structure, since moisture does not penetrate the organic light emitting device by riding on the pixel definition layer, it is possible to solve the problem of deterioration of the organic light emitting device prematurely by water.

Description

Organic light emitting display apparatus and method for manufacturing same

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic light emitting display device and a method of manufacturing the same, and more particularly, to an organic light emitting display device having an improved structure so as to suppress moisture penetration into an active region and a method of manufacturing the same.

2. Description of the Related Art Generally, an organic light emitting display includes a thin film transistor and an organic light emitting diode. The organic light emitting diode emits light by receiving a proper driving signal from the thin film transistor, thereby realizing a desired image.

The thin film transistor has a structure in which an active layer, a gate electrode, a source and drain electrode, and the like are stacked on a substrate. Accordingly, when a current is supplied to the gate electrode through the wiring formed on the substrate, a current flows to the source / drain electrode via the active layer, and a current flows to the pixel electrode of the organic light emitting device connected to the source / drain electrode.

The organic light emitting element includes the pixel electrode, a facing electrode facing the pixel electrode, and a light emitting layer interposed between the two electrodes. When a current flows to the pixel electrode through the thin film transistor as described above, an appropriate voltage is formed between the counter electrode and the pixel electrode, so that light is emitted from the light emitting layer, thereby realizing an image.

However, in particular, the light emitting layer of the organic light emitting device has a very weak characteristic to moisture. Therefore, in order to maintain the performance of the organic light emitting diode display for a long time, a structure capable of sufficiently suppressing moisture penetration from the outside is required. Of course, the sealant is applied around the active area on the substrate including the organic light emitting element and the thin film transistor and covers the glass substrate to block outside air and moisture, but it is more frequent because moisture is frequently introduced through the sealant. Preparedness is required.

Embodiments of the present invention provide an organic light emitting display device and a method of manufacturing the same, which have a function of suppressing moisture penetration into an active region.

An organic light emitting diode display according to an exemplary embodiment of the present invention includes an active region in which an organic light emitting element and a pixel definition layer defining a light emitting region of the organic light emitting element are formed on a substrate, and a sealant is provided to seal the active region with an encapsulation substrate. And a sealant region to be coated, wherein the active region is divided into an active first region in which the organic light emitting diode is disposed and an active second region between the sealant region and the active first region, and the active first region and the active region. The pixel definition layer is removed between the active second regions.

A liquid getter may be provided in the active second region of the active region.

The organic light emitting diode may include a pixel electrode, a light emitting layer formed in a light emitting region partitioned by the pixel definition layer on the pixel electrode, and an opposing electrode formed on the light emitting layer and the pixel definition layer. It may be formed on the counter electrode in the active second region.

The active region may include an active layer, a gate electrode, and a source drain electrode to be connected to the organic light emitting diode.

The active region further includes a first wiring layer formed on the same layer as the gate electrode, and a second wiring layer formed on the same layer as the source drain electrode through an insulating layer on the first wiring layer and covered by the pixel definition layer. The second wiring layer may be connected via the first wiring layer via a bridge between the active first region and the active second region from which the pixel definition layer is removed.

Further, a method of manufacturing an organic light emitting display device according to an embodiment of the present invention includes an active forming step of forming an active region including an organic light emitting element and a pixel definition layer partitioning a light emitting region of the organic light emitting element on a substrate; And a sealing step of applying a sealant to the sealant area around the active area and covering the encapsulation substrate, wherein the active forming step includes: an active first area in which the organic light emitting element is disposed; And removing the pixel defining layer between the active first region and the active second region so as to be divided into an active second region between the sealant regions.

The method may further include forming a liquid getter in the active second region of the active region.

The organic light emitting diode may include a pixel electrode, a light emitting layer formed in a light emitting region partitioned by the pixel defining layer on the pixel electrode, and an opposing electrode formed on the light emitting layer and the pixel definition layer. The second electrode may be formed on the counter electrode.

The active region may include a thin film transistor having an active layer, a gate electrode, and a source drain electrode connected to the organic light emitting diode.

The active region further includes a first wiring layer formed on the same layer as the gate electrode, and a second wiring layer formed on the same layer as the source drain electrode through an insulating layer on the first wiring layer and covered by the pixel definition layer. The second wiring layer may be connected to the first wiring layer via the bridge between the active first region and the active second region from which the pixel definition layer is removed.

As described above, the organic light emitting diode display and the method of manufacturing the same may remove the pixel definition layer, which may be a moisture penetration path, around the active region in which the organic light emitting diode is located, thereby preventing moisture from penetrating into the organic light emitting diode. Therefore, by using this, it is possible to solve the problem that the organic light emitting device is degraded early by moisture.

1 is a cross-sectional view illustrating an organic light emitting display according to an embodiment of the present invention.
2A through 2H are cross-sectional views sequentially illustrating a manufacturing process of the OLED display illustrated in FIG. 1.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Like reference numbers in the drawings denote like elements. In the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

In the drawings illustrating embodiments of the present invention, some layers or regions are shown in enlarged thickness for clarity of the description. Also, when a section of a layer, film, region, plate, or the like is referred to as being "on" another section, it includes not only the case where it is "directly on" another part but also the case where there is another part in the middle.

1 is a cross-sectional view schematically illustrating a portion of a bottom emission organic light emitting display device according to an exemplary embodiment of the present invention.

Referring to FIG. 1, an organic light emitting diode display according to an exemplary embodiment of the present invention provides an active region A in which a thin film transistor TFT, an organic light emitting element EL, and the like are formed, and an encapsulation substrate 70 on a substrate 10. A sealant region S for applying the sealant 60 is provided.

First, referring to the structure of the active region A, the thin film transistor TFT includes an active layer 21, a gate electrode 20, a source / drain electrode 27/29, and the like. The gate electrode 20 includes a gate lower electrode 23 and a gate upper electrode 25, and the gate lower electrode 23 is formed of a transparent conductive material. A gate insulating layer 15 (hereinafter referred to as a first insulating layer) is disposed between the gate electrode 20 and the active layer 21 to insulate them. In addition, a source / drain region in which a high concentration of impurities are injected is formed at both edges of the active layer 21, so that the source / drain electrodes 27/29 are connected to the active layer 21.

The organic light emitting element EL includes a pixel electrode 31 connected to one of the source / drain electrodes 27/29 of the thin film transistor TFT, an opposite electrode 35 serving as a cathode, and the pixel electrode ( 31 and the light emitting layer 33 interposed between the counter electrode 35.

Reference numerals 22 and 28 denote first and second wiring layers used for power supply wiring and signal wiring, respectively.

Reference numeral 55 denotes a pixel definition layer that partitions the emission region of the organic light emitting element EL. The pixel defining layer 55 is formed to cover the active region A as a whole except for the light emitting region. At the point close to the sealant region S, the pixel defining layer 55 is removed to remove the valley 55a. This formed site is present. If the bone 55a is made in this way, it becomes an effective structure for preventing the penetration of moisture from the outside. That is, the active region A is formed into an active first region A1 including the organic light emitting element EL and a thin film transistor TFT, and an active second region A2 close to the sealant region S. In other words, the valley 55a in which the pixel defining layer 55 is broken is formed between the active first region A1 and the active second region A2. The reason why the pixel defining layer 55 is cut off is that it serves as a path for moisture penetration of the pixel defining layer 55. That is, when moisture passes through the sealant 60 and enters the active region A, moisture may penetrate through the pixel definition layer 55 to the organic light emitting element EL. Of course, although a moisture absorbent such as the liquid getter 61 is provided to remove moisture, since it is disposed above the pixel definition layer 55, moisture entering through the side adjacent to the sealant region S may be prevented. it's difficult. In addition, if the liquid getter 61 is formed to cover the side surface of the pixel definition layer 55 to prevent this, the moisture blocking ability may be improved, but the dead space is widened. However, when the active first region A1 and the active second region A2 of the pixel definition layer 55 are disconnected as in the present embodiment, the penetration path of moisture is blocked, thereby making the structure complicated. The moisture barrier can be further improved without modification. Only one side of the active region A is shown in the drawing. In fact, the valley 55a is formed by rotating the periphery of the active region A, and the pixel defining layer 55 is removed, and the valley 55a is formed. It is assumed that the inside of the inside becomes the active first area A1 and the outside becomes the active second area A2.

Hereinafter, a method of manufacturing an organic light emitting display device having such a structure will be described with reference to the drawings.

2A through 2H are cross-sectional views sequentially illustrating a manufacturing process of the organic light emitting diode display illustrated in FIG. 1.

First, referring to FIG. 2A, a buffer layer 11 is formed on the substrate 10 to block smoothness of the substrate 10 and penetration of impurity elements.

The substrate 10 may be formed of a transparent glass material having SiO2 as a main component. The substrate 10 is not limited thereto, and various substrates such as a transparent plastic material or a metal material can be used.

An active layer 21 of a thin film transistor (TFT) is formed on the buffer layer 11. The active layer 21 may be formed of a polycrystalline silicon material and is patterned by a mask process using a first mask (not shown). Thereafter, a first insulating layer 15 is formed on the patterned active layer 21. The first insulating layer 15 may deposit an inorganic insulating film such as SiNx or SiOx by a PECVD method, an APCVD method, or an LPCVD method. The first insulating layer 15 is interposed between the active layer 21 of the thin film transistor TFT and the gate electrode 20 to serve as a gate insulating film of the thin film transistor TFT.

Subsequently, as illustrated in FIG. 2B, the first conductive layer 17 and the second conductive layer 19 are sequentially deposited on the first insulating layer 15, and then the pixel electrode 31 of the organic light emitting element EL is formed. ), The gate electrode 20 and the first wiring layer 22 of the thin film transistor TFT are patterned.

The first conductive layer 17 may include one or more materials selected from transparent materials such as ITO, IZO, ZnO, or In2O3. The second conductive layer 19 may include at least one selected from the group consisting of Ag, Mg, Al, Pt , Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, Mo, Ti, W, MoW and Al / Cu.

The first conductive layer 17 and the second conductive layer 19 are sequentially stacked on the entire surface of the substrate 10, and then patterned by a mask process using a second mask (not shown) to form the gate electrode 20 and the gate electrode 20. The pixel electrode 31 and the first wiring layer 22 are formed.

The gate electrode 20 corresponds to the center of the active layer 21. In this state, when the active layer 21 is doped with an n-type or p-type impurity using the gate electrode 20 as a mask, A channel portion is formed in the active layer 21 region, and a source drain portion is formed in an edge not covered.

2C, the second insulating layer 50 is deposited on the entire surface of the substrate 10 on which the gate electrode 20 is formed, and the openings H1 are formed through a mask process using a third mask (not shown). , H2, H3, H4, H5, H6).

The second insulating layer 50 may be formed by spin coating at least one organic insulating material selected from the group consisting of polyimide, polyamide, acrylic resin, benzocyclobutene and phenol resin, and the first insulating layer described above. It is formed thicker than 15 so as to serve as an interlayer insulating film between the gate electrode 20 and the source / drain electrodes 27/29 of the thin film transistor. Meanwhile, the second insulating layer 50 may be formed of an inorganic insulating material such as the first insulating layer 15 as well as the organic insulating material as described above, and may be formed by alternating an organic insulating material and an inorganic insulating material. You may.

The second insulating layer 50 is patterned by a third mask process so that openings H1 exposing the source drain portion, which is an edge of the active layer 21, and a portion of the pixel electrode 31 and the first wiring layer 22 are exposed. , H2, H3, H4, H5, H6).

Subsequently, referring to FIG. 2D, a third conductive layer is deposited on the entire surface of the substrate 10 on the second insulating layer 50, and patterned by a fourth mask process to form the source drain electrodes 27 and 29 and the second. The wiring layer 28 is formed.

The third conductive layer may be selected from the same conductive materials as the first or second conductive layers 17 and 19, or may be formed of a Mo / Al / Mo material.

The third conductive layer 53 is patterned to form source drain electrodes 27 and 29 and a second wiring layer 28, wherein the pixel electrode 31 is etched to expose the first conductive layer 17. do. Meanwhile, although not shown in the cross-sectional view, one electrode 29 of the source drain electrodes 27 and 29 is connected to the pixel electrode 31. The second wiring layer 28 is not connected to the straight lines in the active region A in a straight line, but is connected in a bridge structure via the first wiring layer 22. The reason for this is because the valley 55a from which the pixel definition film 55 is removed as described above is directly formed on the bridge structure in the next step. If the second wiring layer 28 is formed without a bridge connection in this way, as the valleys 55a are formed, the second wiring layer 28 is immediately exposed, and the counter electrode 35 to be formed later. Since short circuits can occur, make a bridge connection to prevent them.

Next, referring to FIG. 2E, the pixel define layer (PDL) 55 is now formed on the substrate 10. The pixel defining layer 55 may be formed by one or more organic insulating materials selected from the group consisting of polyimide, polyamide, acrylic resin, benzocyclobutene, and phenol resin by spin coating.

The pixel defining layer 55 is patterned through a fifth mask process to expose the central portion of the pixel electrode 31, that is, the light emitting region, and as described above, the active first region A1 and the active second region ( A valley 55a that divides A2) is formed. Accordingly, the pixel defining layer 55 is cut between the active second region A2 adjacent to the sealant region S and the active first region A1 including the organic light emitting element EL. Therefore, even if moisture enters from the outside, the organic light emitting element EL cannot penetrate through the pixel definition layer 55.

Thereafter, as shown in FIG. 2F, the light emitting layer 33 is formed in the light emitting region on the pixel electrode 31, and then the counter electrode 35 is formed.

The emission layer 33 is an organic emission layer (EML), a hole transport layer (HTL), a hole injection layer (HIL), an electron transport layer (ETL), and Any one or more layers of a functional layer such as an electron injection layer (EIL) may be formed by stacking a single or a complex structure.

The counter electrode 35 is deposited on the entire surface of the substrate 10.

Subsequently, as shown in FIG. 2G, the liquid getter 61, which is a moisture absorbent, is formed on the counter electrode 35 on the active second region A2. Moisture that has penetrated from the outside and does not fall into the active first region A1 and remains in the active second region A2 is absorbed and removed by the liquid getter 61. And, the liquid getter 61 is not preferably formed on the valley (55a). Since the gap between the counter electrode 35 and the first wiring layer 22 is very narrow in the valley 55a region, if the liquid getter 61 is formed also on the valley 55a, the calcium oxide in the liquid getter 61 is opposed. A short may be generated by pressing the electrode 35. Accordingly, the liquid getter 61 is formed on the counter electrode 35 of the active second region A2 except for the valley 55a region.

Thereafter, as shown in FIG. 2H, the sealant 60 is coated and the sealing substrate 70 is bonded thereon to seal the active region A. As shown in FIG.

Through such a process, it is possible to implement a structure that can easily and effectively block moisture infiltration into the organic light emitting device (EL).

Therefore, according to the organic light emitting diode display and the manufacturing method thereof according to the embodiment of the present invention, the pixel definition layer which may be a moisture penetration path is removed around the active region in which the organic light emitting element is located, so that moisture does not penetrate to the organic light emitting element. Because it prevents the blocking, it can solve the problem that the organic light emitting device is deteriorated early by moisture.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation and that those skilled in the art will recognize that various modifications and equivalent arrangements may be made therein. It will be possible. Accordingly, the true scope of protection of the present invention should be determined only by the appended claims.

10 ... substrate 11 ... buffer layer
20 gate electrode 31 pixel electrode
33 Light emitting layer 35 Counter electrode
55 ... Pixel Justice 60 ... Sealant
61.Liquid getter 70 ... Bar board
22 ... first wiring layer 28 ... second wiring layer
A ... active area A1 ... active first area
A2 ... active second area S ... silent area

Claims (10)

An organic light emitting element and a pixel definition layer for partitioning a light emitting region of the organic light emitting element include an active region formed on a substrate, and a sealant region to which a sealant is applied to seal the active region with a sealing substrate;
The active region is divided into an active first region in which the organic light emitting diode is disposed, and an active second region between the sealant region and the active first region, and the pixel between the active first region and the active second region. An organic light emitting display device with a positive layer removed. The method of claim 1,
And a liquid getter in the active second area of the active area. 3. The method of claim 2,
The organic light emitting diode includes a pixel electrode, a light emitting layer formed in a light emitting region partitioned by the pixel definition film on the pixel electrode, and an opposite electrode formed on the light emitting layer and the pixel definition film,
The liquid getter is formed on the counter electrode in the active second region. The method of claim 1,
And a thin film transistor having an active layer, a gate electrode, and a source drain electrode connected to the organic light emitting diode in the active region. 5. The method of claim 4,
The active region further includes a first wiring layer formed on the same layer as the gate electrode, and a second wiring layer formed on the same layer as the source drain electrode through an insulating layer on the first wiring layer and covered by the pixel definition layer. ,
And a second wiring layer connected between the active first region and the active second region from which the pixel definition layer is removed via the first wiring layer via a bridge. An active forming step of forming an active region including an organic light emitting element and a pixel definition layer partitioning a light emitting region of the organic light emitting element on a substrate, and a sealing step of applying a sealant to the sealant region around the active region and covering the encapsulation substrate. Including;
In the active forming step, the active first region and the active agent are divided into an active first region in which the organic light emitting element is disposed and an active second region between the active first region and the sealant region. And removing the pixel definition layer between two regions. The method according to claim 6,
And forming a liquid getter in the active second region of the active region. 8. The method of claim 7,
The organic light emitting diode includes a pixel electrode, a light emitting layer formed in a light emitting region partitioned by the pixel definition film on the pixel electrode, and an opposite electrode formed on the light emitting layer and the pixel definition film,
And forming the liquid getter on the counter electrode in the active second region. The method according to claim 6,
And a thin film transistor having an active layer, a gate electrode, and a source drain electrode connected to the organic light emitting element in the active region. 10. The method of claim 9,
The active region further includes a first wiring layer formed on the same layer as the gate electrode, and a second wiring layer formed on the same layer as the source drain electrode through an insulating layer on the first wiring layer and covered by the pixel definition layer. ,
And manufacturing the second wiring layer via the first wiring layer via a bridge between the active first region and the active second region from which the pixel definition layer is removed.

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