KR20150112447A - Organic light emitting display display device and method for manufacturing the same - Google Patents

Abstract

Provided are an organic light emitting display device and a method for manufacturing the same. The method for manufacturing an organic light emitting display device may include the following steps: forming a substrate which includes a white sub-pixel, red sub-pixel, green sub-pixel, and blue sub-pixel, each of which includes a light emitting area and a device area; arranging multiple thin film transistors which include at least one switching thin film transistor in each device region, and a driving thin film transistor connected to the switching thin film transistor; forming an organic light emitting device in each light emitting region; and forming a cutting pattern in the light emitting region of the white sub-pixel, wherein the cutting pattern is for separating non-emitting parts from the white sub-pixel.

Description

TECHNICAL FIELD [0001] The present invention relates to an organic light emitting diode (OLED) display device and a method of manufacturing the same.

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an organic light emitting display and a method of manufacturing the same, and more particularly, to an organic light emitting display capable of preventing pixel defects due to foreign substances and a method of manufacturing the same.

As the era of informationization becomes full-scale, the display field for visually displaying electrical information signals is rapidly developing. Accordingly, studies have been continuing to develop performance such as thinning, light weight, and low power consumption for various flat display devices.

Typical examples of such flat panel display devices include a liquid crystal display device (LCD), a plasma display panel (PDP), a field emission display (FED) An electro-luminescence display device (ELD), an electro-wetting display device (EWD), and an organic light emitting display device (OLED).

Meanwhile, an active matrix driving mode flat panel display device includes a cell array for independently driving a plurality of pixel regions.

The cell array includes a plurality of switching elements which are formed so as to correspond to a plurality of pixel regions in a crossing region of a gate line and a data line and a gate line and a data line which are arranged to cross each other to define a plurality of pixel regions.

Further, the organic light emitting display device basically includes an anode and a cathode, and a light emitting layer interposed between the two electrodes. By applying a voltage to the anode and the cathode, holes and electrons move to the light emitting layer, and holes and electrons moved to the light emitting layer combine to emit light.

At this time, a so-called dark spot which does not emit light even when a voltage is applied to the positive electrode and the negative electrode due to the shorting of the positive electrode and the negative electrode may occur.

Specifically, a dark spot may be generated by particles generated at the time of forming the light emitting layer or the cathode. In this case, dark pixels which do not emit light among the pixels of the organic light emitting display device are generated, which may lead to defects of the organic light emitting display device.

Therefore, a short circuit between the anode and the cathode at the local site causes a defect in a dark spot where a specific pixel does not emit light. Such a defect in the dark point may reduce the reliability of the organic light emitting display device and cause the organic light emitting display device to lose its quality and be discarded. Accordingly, there is a limitation in improving the yield of a flat panel display device such as an organic light emitting display device.

In addition, when a defect in a dark spot occurs after a flat panel display device is commercialized as a display module, a manufacturing cost and a manufacturing time for commercialization of the flat panel display device are unnecessarily consumed.

 [Related Technical Literature]

1. Method for manufacturing flat panel display (Patent Application No. 10-2012-0152803)

2. Organic electroluminescence display device and method of manufacturing the same (Patent Application No. 10-2005-0080331)

In recent years, products with high quality display such as full HD (full HD) or UHD have been released, and customers have improved eye level of organic light emitting display devices, There is a demand for a product which requires a product or minimizes the number of darkened pixels to, for example, 5 or less.

Since the display region of the organic light emitting diode display device has tens to tens of millions of pixel regions, the failure cost is greatly increased in manufacturing all of the pixel regions so as not to cause defects, thereby increasing the manufacturing cost have. In particular, in a WRGB type organic light emitting display device using a white sub-pixel, a red sub-pixel, a green sub-pixel and a blue sub-pixel, the occurrence of a dark spot in a white sub-pixel can be more easily seen.

The inventors of the present invention invented a method of manufacturing an organic light emitting display device capable of improving the yield by repairing defect of a defect in a dark spot generated in a display area in an organic light emitting display device.

Accordingly, an object of the present invention is to provide an OLED display device having a WRGB sub-pixel structure, in which a defective display region does not emit light when a dark point defect occurs in a white sub-pixel, .

The solutions according to one embodiment of the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

There is provided an organic light emitting display device in which a defect of a dark spot is removed in a display region of a white sub-pixel according to an embodiment of the present invention and a manufacturing method thereof

A red sub-pixel, a green sub-pixel, and a blue sub-pixel, each of which is provided with a light emitting region, a light emitting region, and an element region. A plurality of thin film transistors including at least one switching thin film transistor and one driving thin film transistor connected thereto are arranged in each element region. An organic light emitting element is formed in each light emitting region. A cut pattern is formed in the light emitting region of the white sub-pixel. And the cut pattern is for separating the non-light emitting portion from the white sub-pixel.

According to another aspect of the present invention, a plurality of thin film transistors are characterized by being a coplanar structure sequentially formed in order of active, gate, and source / drain.

According to another aspect of the present invention, the cut pattern is the same material as the source electrode and the drain electrode.

According to another aspect of the present invention, an organic light emitting device includes a pixel electrode, an organic light emitting layer, and a cathode electrode.

According to still another aspect of the present invention, the pixel electrode is formed of ITO.

According to still another aspect of the present invention, the cut pattern is the same material as the pixel electrode.

According to another aspect of the present invention, an organic light emitting diode display includes an insulating layer on a substrate.

According to another aspect of the present invention, the insulating layer includes an opening in a part of the white sub-pixel, and the cut-out pattern is directly connected to the pixel electrode in the opening.

According to another aspect of the present invention, an organic light emitting diode display includes a planarization layer on a substrate.

According to another aspect of the present invention, the planarization layer includes an opening in a portion of the white sub-pixel, and the cut-off pattern is directly connected to the pixel electrode through the opening.

According to still another aspect of the present invention, the organic light emitting element has a non-emission region in a part of the white sub-pixel.

According to another aspect of the present invention, an OLED display further includes a bank layer in a non-emission region, and the bank layer covers a cut pattern in a white sub-pixel.

According to another aspect of the present invention, the white sub-pixel has a larger area than the red sub-pixel, the blue sub-pixel, and the green sub-pixel.

A manufacturing method of a flexible display device according to an embodiment of the present invention is provided.

A plurality of thin film transistors corresponding to white subpixels, red subpixels, green subpixels, and blue subpixels, each having a light emitting region and an element region, are formed on one surface of a substrate. And an organic light emitting element is formed in each light emitting region. A cut pattern is formed in the light emitting region of the white sub-pixel of the substrate. The laser beam of the first wavelength range is selectively irradiated to the cut pattern to repair the defect of the dark spot of the white sub-pixel.

According to another aspect of the present invention, the step of forming the organic light emitting device includes sequentially forming the pixel electrode, the organic light emitting layer, and the upper electrode.

According to another aspect of the present invention, the step of forming a cut pattern includes the step of forming a cut pattern on the same layer as the pixel electrode.

According to another aspect of the present invention, a method of fabricating an organic light emitting display further includes forming a passivation layer on the substrate and forming an opening in the passivation layer in the white sub-pixel emission region.

According to another aspect of the present invention, a method of fabricating an organic light emitting display includes forming a planarization layer on a substrate, and forming an opening in the planarization layer in the emission region of the white sub-pixel .

According to still another aspect of the present invention, the step of forming a plurality of thin film transistors includes the step of sequentially forming an active layer, a gate electrode, a source electrode, and a drain electrode.

According to still another aspect of the present invention, the step of forming a cut pattern includes the step of forming a cut pattern of the same material as the source electrode and the drain electrode in the opening portion of the white sub pixel emission region.

According to another aspect of the present invention, there is provided a method of manufacturing an organic light emitting display, comprising: checking whether a dark pixel of a white sub-pixel of a substrate is generated; And laser repairing the cut pattern located in the light emitting region of the light emitting region.

The details of other embodiments are included in the detailed description and drawings.

FIG. 1 is a plan view of a WRGB-type organic light emitting display including a cutting pattern according to an embodiment of the present invention.
2A and 2B are schematic plan views illustrating a cutting pattern located in a white sub-pixel according to an embodiment of the present invention.
FIGS. 3A and 3B are cross-sectional views of the cutting pattern of FIGS. 2A and 2B taken along the cutting lines IIIa-IIIa 'and IIIb-IIIb', respectively.
4 is a flowchart illustrating a method of manufacturing an OLED display according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and the manner of achieving them, will be apparent from and elucidated with reference to the embodiments described hereinafter in conjunction with the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims.

The shapes, sizes, ratios, angles, numbers, and the like disclosed in the drawings for describing the embodiments of the present invention are illustrative, and thus the present invention is not limited thereto. Like reference numerals refer to like elements throughout the specification. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail. Where the terms "comprises", "having", "done", and the like are used in this specification, other portions may be added unless "only" is used. Unless the context clearly dictates otherwise, including the plural unless the context clearly dictates otherwise.

In interpreting the constituent elements, it is construed to include the error range even if there is no separate description.

In the case of a description of the positional relationship, for example, if the positional relationship between two parts is described as 'on', 'on top', 'under', and 'next to' Or " direct " is not used, one or more other portions may be located between the two portions.

An element or layer is referred to as being another element or layer "on ", including both intervening layers or other elements directly on or in between.

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

Like reference numerals refer to like elements throughout the specification.

The sizes and thicknesses of the individual components shown in the figures are shown for convenience of explanation and the present invention is not necessarily limited to the size and thickness of the components shown.

It is to be understood that each of the features of the various embodiments of the present invention may be combined or combined with each other, partially or wholly, and technically various interlocking and driving are possible, and that the embodiments may be practiced independently of each other, It is possible.

Various embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

1 is a plan view of a WRGB organic light emitting display device including a cutting pattern according to an embodiment of the present invention.

Referring to FIG. 1, an OLED display 100 includes a display substrate 110 defined by a plurality of pixels 120 having a light emitting region 130 and a device region 140. In FIG. 1, the light emitting region 130 is shown by a dot-dash line and the device region 140 is shown by a dotted line.

The display substrate 110 is a substrate for supporting and protecting various elements of the OLED display 100. A flexible substrate having flexibility capable of being bent by the display substrate 110 can be used.

The display substrate 110 includes a plurality of pixels. In FIG. 1, only one pixel 120 of the OLED display 100 is shown for convenience of explanation.

For convenience of description, a region where the organic light emitting element is formed in each pixel 110 is referred to as a light emitting region 130, and a region where a switching and driving thin film transistor and a storage capacitor Cst are formed is defined as an element region 140 Respectively.

The pixel 120 includes a light emitting region 130 and an element region 140 for driving the pixel.

The light emitting region 130 includes a red sub-pixel 130R, a white sub-pixel 130W, a blue sub-pixel 130B, and a green sub-pixel 130G. The luminescent region 130 has a rectangular shape and is an upper region within the pixel 120 indicated by the one-dot chain line in Fig.

The device region 140 includes thin film transistors and is the lower region within the pixel 120 indicated by the dotted line in Fig.

Referring to FIG. 1, the white sub-pixel 130W and the blue sub-pixel 130B may be designed to have a larger area than the remaining sub-pixels. Each pixel has a different lifetime, luminance, and color temperature. In particular, the luminance of the blue sub-pixel 130B is lower than that of the other sub-pixels. Therefore, in order to increase the lifetime of the blue sub-pixel 130B, it is necessary to make the area of the blue sub-pixel 130B larger than that of the other sub-pixels. In order to increase the brightness of all the pixels, it is necessary to make the area of the white sub-pixel 130W larger than that of the other sub-pixels. However, by designing the area to be large, the defect of the dark point (DP) in the white sub-pixel 130W and the blue sub-pixel 130B is increased relative to the other sub-pixels relatively different from each other.

 In Fig. 1, the white sub-pixel 130W of the pixel seems to generate the dark point (DP) more easily than in the other sub-pixels. This is because the white sub-pixel 130W has relatively good visibility. Therefore, in the OLED display 100 according to the embodiment of the present invention, a repair structure is introduced to minimize the defect of the dark point (DP) of the white sub-pixel 130W.

A cut pattern 150 is formed in a part of the white sub-pixel 130W of the pixel 120. [ The white sub-pixel 130W which is not emitted due to the defect of the dark spot DP can be repaired using the cut pattern 150 when a dark point DP is generated in a part of the white sub-pixel 130W. That is, if the cutting pattern 150 located in a part of the white sub-pixel 130W in which the dark spot DP is generated is cut using a laser, only the partial area due to the defect in the dark point DP in the white sub-pixel 130W It is possible to prevent the white sub-pixel 130W from emitting light as a whole.

2A and 2B are schematic plan views for illustrating a cutting pattern located in a white sub-pixel according to an embodiment of the present invention.

Referring to FIGS. 2A and 2B, scan lines 220a and 220b and scan lines 220a and 220b, which are insulated from and intersect with data lines 210a and 210b and data lines 210a and 210b arranged in one direction, Common power supply voltage lines 230a and 230b intersecting and insulated from each other are positioned in parallel to the data lines 210a and 210b. Unit pixels are defined by the data lines 210a and 210b, the scan lines 220a and 220b, and the common power supply voltage lines 230a and 230b. The unit pixels shown in Figs. 2A and 2B are white sub-pixels 200a and 200b. The arrangement of the various lines shown in Figs. 2A and 2B is arbitrary, and each line may be arranged in a different arrangement as long as each function is maintained.

The white sub-pixels 200a and 200b include switching thin film transistors 240a and 240b, driving thin film transistors 250a and 250b, capacitors 260a and 260b, organic light emitting elements 270a and 270b, , And a bank. The switching thin film transistors 240a and 240b are driven by scan signals applied to the scan lines 220a and 220b and transfer data signals applied to the data lines 210a and 210b to the drive thin film transistors 250a and 250b It plays a role. The driving thin film transistors 250a and 250b may include a gate electrode, an active layer, a source electrode, and a drain electrode. The driving thin film transistors 250a and 250b may include data signals transmitted from the switching thin film transistors 240a and 240b, The amount of current flowing through the organic light emitting elements 270a and 270b is determined by a voltage difference between the gate electrode and the source electrode.

The capacitors 260a and 260b store the data signal transmitted through the switching thin film transistors 240a and 240b for one frame.

The organic light emitting devices 270a and 270b include at least pixel electrodes 271a and 271b, an organic light emitting layer, and an upper electrode. The organic light emitting devices 270a and 270b are spaced apart from each other in a part of the white sub-pixels 200a and 200b.

The cut patterns 280a and 280b are formed in a part of the white sub-pixels 200a and 200b. However, there is a difference in the method of forming the cut pattern 280a of FIG. 2A and the cut pattern 280b of FIG. 2B. 2A is formed on the same plane by the same process as the pixel electrode 271a of the organic light emitting diode 270a. The cutting pattern 280a of FIG. 2A may be formed of an indium-tin-oxide (ITO) material. The cut pattern 280a in FIG. 2A has a width narrower than that of the pixel electrode 271a in a part of the white sub-pixel 200a.

The cutting pattern 280b of FIG. 2B is formed on the same plane as the source electrode or the drain electrode of the driving thin film transistor 250b in the same process in a part of the white sub-pixel 200b. The cut pattern 280b electrically contacts the pixel electrode 271b of the organic light emitting element 270b spaced apart from each other in the white sub pixel 200b.

The bank defines each sub-pixel while being positioned between the white sub-pixels 200a and 200b and other adjacent sub-pixels. The bank covers the portions of the white sub-pixels 200a and 200b excluding the light emitting region including the cut patterns 280a and 280b.

FIGS. 3A and 3B are cross-sectional views of the cutting pattern of FIGS. 2A and 2B taken along the cutting lines IIIa-IIIa 'and IIIb-IIIb', respectively. 3A and 3B, the organic light emitting display 300a and 300b includes a substrate, light-shielding layers 310a and 310b, insulating layers 320a and 320b, driving thin film transistors 330a and 330b, planarization layers 340a and 340b ), Bank layers 350a and 350b, organic light emitting devices 360a and 360b, and cut patterns 370a and 370b.

The substrate is a substrate for supporting and protecting various elements of the organic light emitting display devices 300a and 300b. The substrate may be composed of an insulating material, for example, glass or plastic, but not limited thereto, and may be formed of various materials. In the present specification, the substrate is made of glass for convenience of explanation.

When the organic light emitting display 300a or 300b is a flexible organic light emitting display, the substrate may be formed of an insulating material having flexibility. Here, transparent insulating materials having usable flexibility include polyimide (PI), polyetherimide (PEI), polyethyleneterephthalate (PE), polycarbonate (PC) (PMMA), polystyrene (PS), styrene acrylonitrile polymer (SAN), silicone-acrylic resin, and the like.

The OLED display devices 300a and 300b may include a plurality of pixel regions. The plurality of pixel regions are regions for displaying one color, and may include a plurality of sub pixel regions. Each of the plurality of pixel regions may include a red sub-pixel region, a green sub-pixel region, and a blue sub-pixel region, and may further include a white sub-pixel region for lowering power consumption and improving brightness. In the present specification, the pixel region may be referred to as a pixel, and the sub pixel region may be referred to as a sub-pixel.

Shading layers 310a and 310b are formed on the substrate. The characteristics of the driving thin film transistors 330a and 330b may be affected when light is incident from the outside. The driving thin film transistors 330a and 330b are formed in the driving region DA. The driving thin film transistors 330a and 330b include gate electrodes 331a and 331b, active layers 332a and 332b, source and drain electrodes 333a and 333b, and driving thin film transistors 330a and 330b Will be described later with reference to Figs. 3A and 3B. The light shielding layers 310a and 310b are light blocking layers for preventing a change in characteristics of the driving thin film transistors 330a and 330b. The light shielding layers 310a and 310b are formed to be wider than the widths of the active layers 332a and 332b of the driving thin film transistors 330a and 330b. It is sufficient that the light shielding layers 310a and 310b can block or reflect light. The light shielding layers 310a and 310b may be made of metal or the like.

Insulating layers 320a and 320b are formed on the substrate. As shown in FIGS. 3A and 3B, the insulating layers 320a and 320b include buffer layers 321a and 321b, gate insulating layers 322a and 322b, interlayer insulating layers 323a and 323b, and passivation layers 324a and 324b ).

Buffer layers 331a and 331b are formed on the substrate including the light shielding layers 310a and 310b. The buffer layers 331a and 331b prevent penetration of moisture or impurities through the substrate, and can flatten the surface of the substrate. However, the buffer layers 331a and 331b are not necessarily required, and may be adopted depending on the substrate type and the type of the thin film transistor used in the organic light emitting display devices 300a and 300b.

The material to be applied to the buffer layers 331a and 331b may be selected according to the interface characteristics with the active layers 332a and 332b depending on the structure of the thin film transistor. For example, as shown in FIGS. 3A and 3B, when the driving thin film transistors 330a and 330b are thin film transistors of a coplanar structure, it is preferable to use a silicon oxide film in accordance with the interface characteristics with the active layers 332a and 332b It may be advantageous in terms of the efficiency of the thin film transistor. The buffer layers 331a and 331b may be formed as a single layer as described above, or may be formed of a plurality of layers. When the buffer layers 331a and 331b are formed of a plurality of layers, the buffer layers 331a and 331b may be formed by alternately stacking a silicon oxide film and a silicon nitride film.

Referring to FIGS. 3A and 3B, gate insulating films 332a and 332b are formed on a substrate. The gate insulating film 132A insulates the active layers 332a and 332b from the gate electrodes 331a and 331b. The gate insulating films 332a and 332b may be formed of a silicon oxide film, a silicon nitride film, or a multi-layer thereof. However, the gate insulating films 332a and 332b may be formed of various materials. Since the gate insulating films 332a and 332b only have to insulate the active layers 332a and 332b and the gate electrodes 331a and 331b from each other, the gate insulating films 332a and 332b are formed only on the active layer 121A .

Interlayer insulating films 333a and 333b are formed on the substrate. The interlayer insulating films 333a and 333b may be formed of the same material as the gate insulating films 332a and 332b and may be formed of a silicon oxide film, a silicon nitride film, or a multilayer thereof. However, have. The interlayer insulating films 333a and 333b may be formed to have contact holes that open partial areas of the active layers 332a and 332b and contact holes may be formed in the source and drain regions of the active layers 332a and 332b It can be opened.

Passivation films 324a and 324b may be formed over the entire surface of the substrate including the source and drain electrodes 333a and 333b. The passivation films 324a and 324b may be formed of the same material as the interlayer insulating films 333a and 333b and / or the gate insulating films 332a and 332b as a protective layer and may be formed of a single Layer or a multi-layer thereof, but may be formed of various materials without limitation. Referring to FIG. 3B, the passivation film 324b may be formed to have a contact hole for opening a part of the cut pattern 370b. The cut pattern 370b is formed on the same plane as the source electrode or the drain electrode of the driving thin film transistor 250b in a part of the white sub-pixel 200b in the same process as described with reference to FIG. 2B. The cut patterns 370a and 370b will be described later.

In general, a switching thin film transistor and a driving thin film transistor 330a and 330b are used to emit the organic light emitting layers 362a and 362b according to image information of a data signal inputted according to a scan signal.

The driving thin film transistors 330a and 330b transmit a current transmitted through the power supply line to the pixels 361a and 361b by the data signal received from the switching thin film transistor and are supplied to the pixel electrodes 361a and 361b And controls the light emission of the organic light-emitting layers 362a and 362b of the corresponding pixel or sub-pixel.

3A and 3B, only the driving thin film transistors 330a and 330b among various thin film transistors that can be included in the organic light emitting display devices 300a and 300b are illustrated for convenience of explanation.

The driving thin film transistors 330a and 330b may be formed on the substrate to emit the organic light emitting layers 362a and 362b. The driving thin film transistors 330a and 330b include gate electrodes 331a and 331b, active layers 332a and 332b and source and drain electrodes 333a and 333b as described above. The driving thin film transistors 330a and 330b may be classified into an inverted-staggered structure and a coplanar structure depending on the positions of the elements constituting the driving thin film transistors 330a and 330b. The driving thin film transistors 330a and 330b of the inverted staggered structure are structured such that the gate electrodes 331a and 331b are located on the opposite sides of the source and drain electrodes 333a and 333b with respect to the active layers 332a and 332b And the driving thin film transistors 330a and 330b having a coplanar structure refer to driving thin film transistors 330a and 330b having gate electrodes 331a and 331b on the source and drain electrodes 331a and 331b on the basis of the active layers 332a and 332b, 333a, and 333b on the same side as the driving thin film transistors 330a and 330b. In this specification, the driving thin film transistors 330a and 330b having the coplanar structure are shown for convenience of explanation, but the driving thin film transistors 330a and 330b having the inverted staggered structure can also be used.

Gate electrodes 331a and 331b are formed on the gate insulating films 332a and 332b. The gate electrodes 331a and 331b are at least partially overlapped with the active layers 332a and 332b and overlap with the channel regions of the active layers 332a and 332b in particular. The gate electrodes 331a and 331b may be formed of one selected from the group consisting of Mo, Al, Cr, Au, Ti, Or alloys thereof, but it is not limited thereto and may be formed of various materials. The gate electrodes 331a and 331b may be formed of at least one selected from the group consisting of Mo, Al, Cr, Au, Or an alloy of any one selected from the group consisting of the above.

Source electrodes and drain electrodes 333a and 333b are formed on the interlayer insulating films 333a and 333b. Each of the source and drain electrodes 333a and 333b is electrically connected to the source and drain regions of the active layers 332a and 332b through contact holes formed in the interlayer insulating films 333a and 333b and / or the gate insulating films 332a and 332b, And can be electrically connected. The source and drain electrodes 333a and 333b may be formed of one selected from the group consisting of Mo, Al, Cr, Au, Ti, Ni, But may be formed of various materials, including, but not limited to, any one or an alloy thereof. The source and drain electrodes 333a and 333b may be formed of at least one selected from the group consisting of Mo, Al, Cr, Au, Ti, ), Or an alloy thereof.

Overcoat layers 340a and 340b are formed over the entire surface of the substrate. Overcoat layers 340a and 340b may also be referred to as planarization films. When the passivation films 324a and 324b are formed, the overcoat layers 340a and 340b may be formed on the passivation film. Overcoat layer 134A flattenes the top of the substrate. The overcoat layers 340a and 340b may be formed to have contact holes exposing the source and drain electrodes 333a and 333b. Further, referring to FIG. 3B, the overcoat layer 340b may be formed to have a contact hole for opening a part of the cut pattern 370b.

In an organic light emitting display device using a white organic light emitting layer and a color filter as in the transparent organic light emitting display devices 300a and 300b according to an embodiment of the present invention, a red sub pixel region, a green sub pixel region, The white organic emission layers 362a and 362b may be formed on the pixels 361a and 361b of the green sub pixel region and the organic emission layers 362a and 362b formed in the red sub pixel region, May be formed over the entire surface of the substrate, or may be separately formed in the light emitting region of each sub pixel region.

On the substrate, organic light emitting elements 360a and 360b including pixel electrodes 361a and 361b, organic light emitting layers 362a and 362b, and an upper electrode are formed. The organic light emitting devices 360a and 360b are formed by combining the holes supplied from the pixel electrodes 361a and 361b and the electrons supplied from the upper electrode by the organic light emitting layers 362a and 362b, Thereby forming an image. The organic light emitting display devices 300a and 300b are independent driving display devices and are driven for each sub-pixel. Therefore, the driving thin film transistors 330a and 330b and the organic light emitting elements 360a and 360b are disposed for each sub-pixel, and the driving thin film transistors 330a and 330b disposed in the respective sub- 360a, and 360b can be independently driven.

The pixel electrodes 361a and 361b are formed on the overcoat layers 340a and 340b. The pixel electrodes 361a and 361b may also be referred to as an anode electrode or a first electrode. The pixel electrodes 361a and 361b are connected to the source electrodes of the driving thin film transistors 330a and 330b through the contact holes formed in the overcoat layers 340a and 340b, And may be connected to the drain electrode depending on the type. Referring to FIG. 3A, the pixel electrode 361a may be used as a cut pattern 370a in a part of the white sub-pixel 200a as described with reference to FIG. 2A. Is formed on the same plane by the same process as the cut pattern 370a. The cut pattern 370a will be described later.

The pixel electrodes 361a and 361b are formed of a conductive material having a high work function because holes must be supplied. The pixel electrodes 361a and 361b may include a transparent conductive layer having a high work function and the transparent conductive layer may be formed of a transparent conductive oxide (TCO), for example, indium tin oxide (ITO) , Indium zinc oxide (IZO), indium tin zinc oxide (ITZO), zinc oxide, and tin oxide.

Bank layers 350a and 350b are formed on the overcoat layers 340a and 340b. The bank layers 350a and 350b serve to distinguish adjacent sub-pixels. Accordingly, the bank layers 350a and 350b are disposed between adjacent sub-pixels. The bank layers 350a and 350b may be formed to open a part of the pixel electrodes 361a and 361b. And the organic light emitting layers 362a and 362b emit light in the opened regions.

Referring to Figures 3a and 3b, bank layers 350a and 350b are formed on the cut patterns 370a and 370b in a portion of the white sub-pixel. The bank layers 350a and 350b are formed so as to cover the cut patterns 370a and 370b in the white sub-pixel partial regions. Therefore, the bank layers 350a and 350b formed in the regions of the organic light emitting elements 360a and 360b of the white sub-pixel separate the non-emitting region from the white sub-pixel. That is, the bank layers 350a and 350b may serve to distinguish the repair region from the non-emission region in one white sub-pixel region. The non-emission region is a region in which a portion of one white sub-pixel region can not emit light due to the occurrence of a dark spot. The repair area RA is an area where the cut patterns 370a and 370b are formed.

The bank layers 350a and 350b may be formed of any one of organic insulating materials, for example, polyimide, photo acryl, and benzocyclobutene (BCB). The bank layers 350a and 350b may be formed in a taper shape. When forming the bank layers 350a and 350b in a tapered shape, the bank layer 135A may be formed using a positive type photoresist.

Referring to FIGS. 3A and 3B, cut patterns 370a and 370b are formed on a substrate including white sub-pixels. The cut patterns 370a and 370b are located in a part of the white sub-pixel. The cut patterns 370a and 370b are patterns that are cut by a laser when a dark spot occurs in a part of white sub-pixels. The cut patterns 370a and 370b can separate areas where non-light emission occurs due to the occurrence of dark points in white sub-pixels. The same material as the source and drain electrodes 333a and 333b or the pixel electrodes 361a and 361b may be used as the cut patterns 370a and 370b.

3A, the case of using the same material as the pixel electrode 361a of the organic light emitting element 360a as the cut pattern 370a will be described.

A pixel electrode 361a is formed on the overcoat layer 340a in the white sub-pixel. The pixel electrode 361a may be formed to have a narrow width in a part of the light emitting region EA of the white sub-pixel. The bank layer 350a is formed on the narrow pixel electrode 361a, that is, the cut pattern 370a, and the bank layer 350a protects and insulates the cut pattern 370a. The organic light emitting layer 360a is formed over the entire surface of the substrate. In some areas of the white sub-pixel where the cut pattern 370a is located, the organic light emitting layer 360a does not emit light due to the bank layer 350a. When a dark spot is generated in the white sub-pixel and the organic light emitting element 360a does not emit light, the cut pattern 370a of the light emitting area EA of the white sub-pixel is broken by laser to separate the non-light emitting area.

It is preferable that the width of the cutout pattern 370a in the light emitting region EA of the white sub-pixel is 5 mu m or less. Thereby, when the cut pattern 370a is cut by the laser, the damage of the peripheral area of the cut pattern 370a can be minimized.

It is preferable that the width of the bank layer 350a that protects the cut pattern 370a is formed so as to minimize the interval between the light emitting regions EA of the white sub-pixels. This is because if the spacing distance is widened, the aperture ratio of the repaired white pixel is reduced, and the luminous efficiency may be lowered.

Referring to FIG. 3B, the case where the source and drain electrodes 333b of the driving thin film transistor 330b are used as the cutout pattern 370b will be described.

Interlayer insulating layers 323a and 323b are formed over the entire surface of the substrate. The cut patterns 370a and 370b may be formed on the interlayer insulating layers 323a and 323b in a part of the white sub-pixel. The cut pattern 370b is electrically connected to the pixel electrode 361b of the organic light emitting element 360b in the contact hole of the passivation film 324b and the overcoat layer 340b. The cut patterns 370a and 370b may be formed on the same plane as the source and drain electrodes 333a and 333b.

When a dark spot occurs in the light emitting area EA of the white sub-pixel, the laser cuts off the cut pattern 370b connected to the light emitting area EA of the white sub-pixel to separate the non-light emitting area.

It is also preferable to form the cutout pattern 370b so that the area of the cutout pattern 370b in the light emitting area EA of the white sub-pixel is minimized. Thereby, when the cut pattern 370a is cut by the laser, the damage of the peripheral area of the cut pattern 370a can be minimized.

4 is a flowchart illustrating a method of manufacturing a transparent organic light emitting display according to an embodiment of the present invention.

First, a plurality of thin film transistors corresponding to the white sub-pixel, the red sub-pixel, the green sub-pixel, and the blue sub-pixel, each having a light emitting region and an element region, are formed on one side of a substrate (S40).

A buffer layer is formed on the entire surface of the substrate. After forming the buffer layer, an active layer, a gate insulating film, and a gate electrode are sequentially formed in the element region, and then an interlayer insulating film is formed on the gate electrode. After forming the interlayer insulating film, source and drain electrodes are formed to form a plurality of thin film transistors.

Subsequently, an organic light emitting element is formed in each light emitting region on the substrate (S41).

A passivation layer and an overcoat layer are formed over the entire surface of the substrate including the source electrode and the drain electrode. The passivation layer and the overcoat layer in the white sub pixel emission region are formed with openings, the passivation layer and the overcoat layer are formed in the white sub pixel device region by contact holes, and the pixel electrode, the organic emission layer, A light emitting element is formed.

Subsequently, a cut pattern is formed in white sub-pixels of the substrate (S43)

The cut pattern may be formed on the same plane as the source and the drain in a part of the white sub-pixel, and may be formed on the same plane as the pixel electrode of the organic light emitting element.

Subsequently, the laser beam of the first wavelength range is selectively irradiated to the cut pattern to repair the defect of the dark spot of the white sub-pixel (S43).

A laser beam having a wavelength band capable of disconnecting only the source and drain electrode materials or the pixel electrode material from the opposite direction in which the thin film transistor and the organic light emitting element of the substrate are formed is irradiated.

When a part of the white sub-pixel is broken by irradiating the laser beam, the white sub-pixel part where the dark point is generated is separated. As a result, the remaining white sub-pixel portion can emit light.

Although the embodiments of the present invention have been described in detail with reference to the accompanying drawings, it is to be understood that the present invention is not limited to those embodiments and various changes and modifications may be made without departing from the scope of the present invention. . Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. Therefore, it should be understood that the above-described embodiments are illustrative in all aspects and not restrictive. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

100, 200a, 200b, 300a, 300b: organic light emitting display
110: Display substrate
120: pixel
130: light emitting region
140:
150, 280a, 280b: cutting pattern
210a and 210b:
220a and 220b:
230a, 230b: a common power supply voltage line
240a and 240b: switching thin film transistors
250a, 250b, 330a, and 330b: a driving thin film transistor
260a and 260b: capacitors
270a and 270b: organic light emitting element
271a, 271b: anode
310a, 310b: Shading layer
320a, 320b: insulating layer
321a and 321b:
322a, 322b: gate insulating layer
323a and 323b: an interlayer insulating layer
324a, 324b: passivation layer
331a and 331b: gate electrodes
332a, 332b: an active layer
333a and 333b: a source electrode and a drain electrode
340a, 340b: planarization layer
350a, 350b: bank layer
360a, 360b: organic light emitting element
361a and 361b:
362a and 362b: organic light-
370a, 370b: cutting pattern

Claims (21)

A substrate including a white sub-pixel, a red sub-pixel, a green sub-pixel, and a blue sub-pixel each having a light emitting region and an element region;
A plurality of thin film transistors including at least one switching thin film transistor in each of the element regions and one driving thin film transistor connected to the switching thin film transistor;
An organic light emitting element formed in each of the light emitting regions; and
A light emitting region of the white sub-pixel including a cut pattern,
Wherein the cut pattern is for separating the non-light emitting portion in the light emitting region of the white sub-pixel. The method according to claim 1,
Wherein the plurality of thin film transistors are a Coplanar structure sequentially formed in order of active, gate, and source / drain. 3. The method of claim 2,
Wherein the cut pattern is the same material as the source electrode and the drain electrode. The method according to claim 1,
Wherein the organic light emitting device includes a pixel electrode, an organic light emitting layer, and a cathode electrode. 5. The method of claim 4,
Wherein the pixel electrode is made of ITO. 5. The method of claim 4,
Wherein the cut pattern is the same material as the pixel electrode. The method according to claim 1,
Further comprising an insulating layer on the substrate. 8. The method of claim 7,
Wherein the insulating layer includes an opening in a portion of the white sub-pixel,
And the cutout pattern is directly connected to the pixel electrode in the opening. The method according to claim 1,
Further comprising a planarization layer on the substrate. 10. The method of claim 9,
Wherein the planarization layer includes an opening in a portion of the white sub-pixel,
And the cutout pattern is directly connected to the pixel electrode through the opening. The method according to claim 1,
Wherein the organic light emitting device has a non-emission region in a part of the white sub-pixel. 12. The method of claim 11,
Further comprising a bank layer in the non-emission region,
And the bank layer covers the cut pattern in the white sub-pixel. The method according to claim 1,
Wherein the white sub-pixel has a larger area than the red sub-pixel, the blue sub-pixel, and the green sub-pixel. Forming a plurality of thin film transistors corresponding to each of a white sub-pixel, a red sub-pixel, a green sub-pixel, and a blue sub-pixel, each having a light emitting region and an element region on one surface of a substrate;
Forming an organic light emitting element in each of the light emitting regions;
Forming a cut pattern in the light emitting region of the white sub-pixel; And
And a step of selectively irradiating the cut pattern with a laser beam of a first wavelength region to repair a defect of a dark spot in the white sub-pixel. 15. The method of claim 14,
Wherein the forming of the organic light emitting device comprises sequentially forming a pixel electrode, an organic light emitting layer, and an upper electrode. 16. The method of claim 15,
Wherein the forming of the cut pattern includes forming the cut pattern on the same layer as the pixel electrode. 15. The method of claim 14,
Forming a passivation layer on the substrate; And
And forming an opening in the passivation layer in the white sub pixel emission region. 15. The method of claim 14,
Forming a planarization layer on the substrate; And
And forming an opening in the planarization layer in the light emitting region of the white sub-pixel. 15. The method of claim 14,
Wherein the forming of the plurality of thin film transistors includes sequentially forming an active layer, a gate electrode, a source electrode, and a drain electrode. 20. The method of claim 19,
Wherein the forming of the cut pattern includes forming the cut pattern with the same material as the source electrode and the drain electrode in the opening of the white sub pixel emission region . 15. The method of claim 14,
Checking whether a dark pixel of the white sub-pixel of the substrate is generated; And
Further comprising laser repairing a cut pattern located in a light emitting region of the white sub-pixel when a dark spot is generated in the white sub-pixel.

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