KR20090094692A - Organic Light Emitting Display - Google Patents

Abstract

An organic electro luminescent display device is provided to prevent the drop of a common voltage supplied to a second electrode by bonding a first substrate with a second substrate having an auxiliary electrode. An organic electro luminescent display device includes a first substrate(110), a plurality of sub pixels, a second substrate(180), and an auxiliary electrode(190). A plurality of sub pixels are arranged on the first substrate in a matrix shape. Each sub pixel includes a first electrode(140), a light emitting layer, and a second electrode(170). The second substrate is boned to the first substrate. The auxiliary electrode is positioned on the second substrate. A part of the auxiliary electrode is contacted with the second electrode. The auxiliary electrode includes a metal electrode, a spacer, an insulating layer, and a common electrode. The metal electrode, the spacer, the insulating layer, and the common electrode are successively stacked on the second substrate.

Description

Organic Light Emitting Display

The present invention relates to an organic light emitting display device.

An organic light emitting display device used in an organic light emitting display device is a self-light emitting device in which a light emitting layer is formed between two electrodes positioned on a substrate.

In addition, the organic light emitting display device may include a top-emission method, a bottom-emission method, or a dual-emission method according to a direction in which light is emitted. According to the driving method, it is divided into a passive matrix type and an active matrix type.

The conventional organic light emitting display device may include a transistor array, a first electrode connected to a source or a drain of the transistor array, an organic light emitting layer formed on the first electrode, and a second electrode formed on the organic light emitting layer.

In the organic light emitting display device having such a structure, when a scan signal, a data signal, a power supply voltage, and the like are supplied to a plurality of sub pixels arranged in a matrix form, the selected sub pixel emits light, thereby displaying an image.

On the other hand, the conventional organic light emitting display device has a problem that a resistance difference occurs depending on the position of the panel due to the resistance characteristics of the electrode material to which the common voltage is supplied. In this case, the display quality is degraded. Such a problem causes a lot of difficulties in realizing the large area of the panel, so it is urgent to prepare a way to solve the problem.

SUMMARY OF THE INVENTION An object of the present invention for solving the above problems of the background art is to prevent the drop of the common voltage supplied to the electrode and to solve the problem that the luminance difference occurs in the panel to improve the display quality organic light emitting display device To provide.

The present invention as a means for solving the above problems, the first substrate; A subpixel including a first electrode, a light emitting layer, and a second electrode on the first substrate and disposed in a matrix; A second substrate spaced apart from the first substrate and bonded to the first substrate; And a protruding auxiliary electrode disposed on the second substrate and partially contacting the second electrode.

At least one auxiliary electrode may be formed on the second substrate so as to be positioned between the subpixels.

The auxiliary electrode may be formed in one direction on the second substrate so as to be positioned between the subpixels.

The auxiliary electrode may be formed in a net shape on the second substrate so as to be positioned between the subpixels.

The auxiliary electrode may include a metal electrode positioned on the second substrate, a spacer positioned on the metal electrode, an insulating layer positioned on the spacer, and a common electrode positioned on the insulating layer.

The auxiliary electrode may include an extension electrode extending from the common electrode and positioned on the second substrate.

The thickness of the extension electrode may be thinner than the thickness of the spacer.

The extension electrode is a transparent electrode and may have a different thickness depending on the region of the second substrate.

The second substrate may include a bonding region bonded to the first substrate, and the extension electrode may be located in all regions inside the bonding region.

The subpixel may include a transistor array positioned on the first substrate and connected to the first electrode.

According to the present invention, an auxiliary electrode in contact with an electrode is formed on a second substrate and the first substrate and the second substrate are bonded to each other to prevent the drop of the common voltage supplied to the electrode and to solve the problem that luminance difference occurs in the panel. There is an effect of providing an organic light emitting display device that can improve the. In addition, the present invention has an effect suitable for large area panel implementation.

Hereinafter, with reference to the accompanying drawings, the specific content for the practice of the present invention will be described.

First Embodiment

FIG. 1A is a schematic plan view of an organic light emitting display device according to a first embodiment of the present invention, FIG. 1B is a cross-sectional view of region XX of FIG. 1A, and FIG. 1C is a plan view of the second substrate shown in FIG. 1A. 1D is another cross-sectional view of region XX of FIG. 1A.

Referring to FIG. 1A, the organic light emitting display device may include a plurality of sub pixels P positioned on the first substrate 110. The plurality of sub pixels P positioned on the first substrate 110 may be driven by the driver 115 to represent an image. Since the plurality of subpixels P disposed on the first substrate 110 are vulnerable to moisture or oxygen, an adhesive material such as a sealant is formed in the adhesive region SL, and the first substrate 110 and the second substrate 180 are formed. ) Can be joined.

The first substrate 110 and the second substrate 180 may be selected as an opaque material such as metal or a transparent material such as glass, but are not limited thereto. In this case, the first substrate 110 and the second substrate 180 shown in the drawing are examples of selecting a transparent material such as glass.

The driver 115 may receive a signal and power required for driving from an external device. The driver 115 may include a scan driver and a data driver for supplying scan signals and data signals to the plurality of subpixels P, which may be separately located. In this case, the illustrated driving unit 115 illustrates that the scan driving unit and the data driving unit are formed as one example.

Hereinafter, a plurality of sub pixels P located on the first substrate 110 will be described in more detail with reference to FIG. 1B.

The transistor array 120 may be located on the first substrate 110. The transistor array 120 may include a semiconductor layer, an interlayer insulating layer, a gate, a gate insulating layer, a source, and a drain. The transistor array 120 will be described in more detail as follows.

The semiconductor layer may be located on the first substrate 110. The semiconductor layer may comprise amorphous silicon or crystallized polycrystalline silicon. In addition, the semiconductor layer may include a source region and a drain region including p-type or n-type impurities, and may include channel regions other than the source region and the drain region.

An interlayer insulating layer may be positioned on the semiconductor layer. The interlayer insulating film may be a silicon oxide film (SiOx), a silicon nitride film (SiNx), or a multilayer thereof, but is not limited thereto.

A gate may be positioned on the interlayer insulating layer corresponding to the semiconductor layer. The gate is any one selected from the group consisting of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd) and copper (Cu) It may be made of an alloy of, but is not limited thereto. In addition, the gate is any one selected from the group consisting of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd) and copper (Cu). Or it may be a multilayer consisting of alloys thereof, but is not limited thereto. In addition, the gate may be a double layer of molybdenum / aluminum-neodymium or molybdenum / aluminum, but is not limited thereto.

On the other hand, the scan wiring to which the scan signal is supplied and the lower electrode of the capacitor to store the data voltage may be located on the same layer as the gate, but is not limited thereto. Scan wiring is any one selected from the group consisting of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd) and copper (Cu) or It may be made of an alloy thereof, but is not limited thereto. In addition, the scan wiring is any one selected from the group consisting of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd) and copper (Cu). It may be, but is not limited to, multiple layers of one or an alloy thereof. In addition, the scan wiring may be a double layer of molybdenum / aluminum-neodymium or molybdenum / aluminum, but is not limited thereto.

The gate insulating layer may be located on the first substrate 110 including the gate. The gate insulating layer may have a via hole through which a portion of the semiconductor layer may be exposed. The gate insulating layer may be, but is not limited to, a silicon oxide layer (SiOx), a silicon nitride layer (SiNx), or a multilayer thereof. When the scan wiring and the lower electrode of the capacitor are positioned on the same layer as the gate, the gate insulating layer may be positioned on the first substrate 110 including the gate, the scan wiring and the lower electrode of the capacitor.

The source and drain may be located on the gate insulating film. The source and the drain are in contact with the source region and the drain region of the semiconductor layer through via holes formed in the gate insulating film. Electrode " 121 " shown in Fig. 1B represents a source or a drain.

The source or drain 121 may be made of a single layer or multiple layers. When the source or drain 121 is a single layer, molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu) It may be made of any one or alloy thereof selected from the group consisting of, but is not limited thereto. In addition, when the source or drain 121 is a multilayer, it may be composed of a double layer of molybdenum / aluminum-neodymium, or a triple layer of molybdenum / aluminum / molybdenum or molybdenum / aluminum-neodymium / molybdenum. On the other hand, the data wiring and the upper electrode and the power wiring of the capacitor may be located on the same layer as the source or drain 121, but is not limited thereto.

The upper upper insulating layer 130 may be positioned on the source or drain 121 of the transistor array 120 described above. The upper insulating layer 130 may have a plurality of contact holes 135 exposing the source or drain 121 of the transistor array 120. The upper insulating layer 130 may be a planarization layer or a protective layer for alleviating the step difference of the lower structure. When the upper insulating layer 130 is a planarization layer, it is a SOG which is coated with an organic material or silicon oxide such as polyimide, benzocyclobutene series resin, acrylate, and the like in a liquid form and then cured. It may be formed of an inorganic material such as (spin on glass), but is not limited thereto. On the other hand, when the upper insulating film 130 is a protective film, this may be a silicon nitride film (SiNx), a silicon oxide film (SiOx) or a multilayer thereof, but is not limited thereto.

A plurality of first electrodes 140 connected to the source or drain 121 of the transistor array 120 may be disposed on the upper insulating layer 130 through a plurality of contact holes 135. The first electrode 140 may be an anode or a cathode, or may be a transparent electrode or a reflective electrode. The material of the first electrode 140 may be selected according to the light emitting direction. For example, when the emission direction is the rear or double-sided light emission, the first electrode 140 may be a transparent electrode, and may be any one of indium tin oxide (ITO), indium zinc oxide (IZO), or zinc oxide (ZnO). But it is not limited thereto.

The bank layer 150 may be positioned on the first electrode 140 and the upper insulating layer 130. The bank layer 150 may have an opening 151 exposing a plurality of first electrodes 140. Here, the opening 151 may be located on the light emitting area AA, and the remaining area except for the opening 151 may be the non-light emitting area NA.

The emission layers 160, 161, and 162 may be positioned on the plurality of first electrodes 140 exposed through the openings 151 formed in the bank layer 150. The emission layers 160, 161, and 162 may be disposed on the lower common layer 160 and the organic emission layer 161 and the organic emission layer 161 on the lower common layer 160. It may include an upper common layer 162 located in.

The second electrode 170 may be positioned on the bank layer 150 including the emission layers 160, 161, and 162. The second electrode 170 may be a cathode or an anode. For example, when the second electrode 170 is a cathode, the work electrode may be made of magnesium (Mg), calcium (Ca), aluminum (Al), silver (Ag), or an alloy thereof, but is not limited thereto.

Hereinafter, the auxiliary electrode positioned on the second substrate 180 will be described in more detail with reference to FIGS. 1B and 1C. An area "PA" displayed on the second substrate 180 of FIG. 1C represents an area corresponding to the plurality of sub pixels P formed on the first substrate 110.

The auxiliary electrode 190 positioned on the second substrate 180 protrudes so that a part of the auxiliary electrode 190 contacts the second electrode 170 positioned between the plurality of sub pixels P formed on the first substrate 110. . When the point where the auxiliary electrode 190 and the second electrode 170 contact each other is set as an area, the auxiliary electrode 190 is an area in which the opening 151 is formed on the first substrate 110, that is, light emission. At least one may be formed on the second substrate 180 to be in contact with the second electrode 170 positioned on the non-light emitting area NA except for the area AA.

The auxiliary electrode 190 will be described in more detail as follows.

The auxiliary electrode 190 includes a metal electrode 191a positioned on the second substrate 180, a spacer 191b positioned on the metal electrode 191a, an insulating layer 191c disposed on the spacer 191b, and an insulating layer. It may include a common electrode 191d positioned on the 191c.

Here, the metal electrode 191a may be a metal having low reflectivity, such as aluminum, molybdenum, titanium, etc., which have relatively high conductivity, but are not limited thereto. The spacer 191b may be formed by patterning an inorganic material or an organic material, but is not limited thereto. The insulating film 191c may be formed by patterning an inorganic material or an organic material, but is not limited thereto and may be omitted if necessary. Here, the insulating film 191c may also have an effect for minimizing the amount of out gassing that may occur in the spacer 191b. In the case of the common electrode 191d, a transparent low resistance material, aluminum, molybdenum, or the like may be used, which may vary depending on the material of the second electrode 170 positioned on the first substrate 110.

The auxiliary electrode 190 may include an extension electrode 192 extending from the common electrode 191d and positioned on the second substrate 180. The thickness of the extension electrode 192 may be thinner than the thickness of the spacer 191b. Here, if the thickness of the extension electrode 192 is different for each region where a plurality of sub pixels P are located, a micro cavity may be realized.

Here, the auxiliary electrode 190 illustrated in FIG. 1C is formed of the extension electrode 192 and the metal electrode 191a, the spacer 191b, the insulating layer 191c, and the common electrode 191d included in the auxiliary electrode 190. In order to facilitate the division, the protruding portion 191 including the metal electrode 191a, the spacer 191b, the insulating layer 191c, and the common electrode 191d may be referred to collectively.

Meanwhile, materials of the common electrode 191d and the extension electrode 192 may vary depending on the material of the second electrode 170. If the material of the second electrode 170 is aluminum and the image is displayed in the direction of the first substrate 110, the material of the common electrode 191d and the extension electrode 192 is made of the same aluminum as the second electrode 170. Similar metals may be employed. In addition, if the material of the second electrode 170 is ITO and the image is displayed in the direction of the second substrate 110, the material of the common electrode 191d and the extension electrode 192 may have the same ITO as the second electrode 170. Can be adopted. However, the present invention is not limited thereto, and various materials may be selected according to the positions of the common electrode 191d and the extension electrode 192.

Here, the material of the first electrode 140 included in the plurality of sub-pixels P included in the organic light emitting display device is an opaque metal such as aluminum, and the material of the second electrode 170 is low such as transparent ITO. Assuming that the resistive oxide is a top emission type that displays an image in the direction of the second substrate 180, the auxiliary electrode can be configured as follows.

A bonding area SL adopting the material of the common electrode 191d positioned on the second substrate 180 as the same ITO as the material of the second electrode 170 and adhering the extension electrode 192 to the first substrate 110. It is formed in the whole inside of the). In this case, since the extension electrode 192 occupies a wide area on the second substrate 180, the common voltage supplied to the second electrode 170 is dropped, thereby reducing the display quality.

However, the present invention is particularly effective for the top emission type organic light emitting display device in which the second electrode 170 is thinly formed of a material such as aluminum. This is because the auxiliary electrode 190 can compensate for the problem that the specific resistance is lowered by the thinly formed second electrode 170 and the common voltage supplied through the second electrode 170 is dropped.

In this case, the material of the second electrode 170 is advantageous to the top emission type organic light emitting display device using a transparent electrode such as ITO. On the other hand, in the case of the bottom emission type organic light emitting display device using an opaque electrode such as aluminum, the material of the second electrode 170 is a limitation when forming the auxiliary electrode 190 on the second substrate 180. Since this is relatively small, there is an advantage in that the configuration of the auxiliary electrode 190 is free.

Meanwhile, referring to FIG. 1D, when the first substrate 110 and the second substrate 180 are bonded to each other, the auxiliary electrode positioned on the second electrode 170 and the second substrate 180 positioned on the first substrate 110 may be provided. In other words, between the protrusions 191 of the electrode 190, a conductive adhesive 195 may be formed between the common electrode 191d and the second electrode 170 to solve a problem in which a short circuit occurs.

In the organic light emitting display device according to the first embodiment of the present invention, the auxiliary electrode 190 is disposed on the second substrate 180 and is included in the auxiliary electrode 190 and the plurality of sub-pixels P. The common voltage (eg, VDD or GND) supplied to the second electrodes 170 of the plurality of subpixels P on the first substrate 110 is dropped by contacting the electrode 170. It can be effective. Therefore, the organic light emitting display device has an effect of providing a uniform display quality and a structure capable of implementing a large area organic light emitting display device.

Second Embodiment

2 is a schematic plan view of an organic light emitting display device according to a second embodiment of the present invention. An area "PA" displayed on the second substrate 280 of FIG. 2 represents an area corresponding to a plurality of sub pixels formed on the first substrate.

The second embodiment of the present invention is similar in configuration to the first embodiment described above. However, since the structure of the auxiliary electrode is different from that of the first embodiment, only the second substrate and the auxiliary electrode will be described in order to avoid duplication of explanation.

The auxiliary electrode 290 of the organic light emitting display device according to the second embodiment may be formed in one direction on the second substrate 280 so as to be positioned in a region between subpixels. In other words, it may be formed in one direction between an area between scan lines to which a scan signal is supplied or between a plurality of subpixels and a corresponding area PA on the second substrate 280.

Here, the auxiliary electrode 290 protrudes so that a part of the auxiliary electrode 290 contacts the second electrode positioned between the plurality of sub pixels formed on the first substrate as in the first embodiment. Therefore, the auxiliary electrode 290 will be described in brief as follows.

The auxiliary electrode 290 may include a metal electrode positioned on the second substrate 280, a spacer positioned on the metal electrode, an insulating layer positioned on the spacer, and a common electrode positioned on the insulating layer. The auxiliary electrode 290 may include an extension electrode 292 extending from the common electrode and positioned on the second substrate 280. The thickness of the extension electrode 292 may be thinner than the thickness of the spacer. The extension electrode 292 may be formed on the entire inner side of the bonding area SL bonded to the first substrate.

Here, the auxiliary electrode 290 illustrated in FIG. 2 is a metal electrode, a spacer, an insulating film in order to facilitate the separation between the extension electrode 292 and the metal electrode, the spacer, the insulating film, and the common electrode included in the auxiliary electrode 290. And a protrusion 291 including a common electrode.

In the second embodiment, unlike the first embodiment, since the length of the metal electrode included in the protrusion 291 is extended, there is an effect of further reducing the problem that the common voltage supplied through the auxiliary electrode 290 is dropped. .

In addition, in the second embodiment, since the extension electrode 292 occupies a large area of the second substrate 280, the common voltage supplied to the second electrode 270 is dropped, thereby reducing the display quality. You can add effects. However, the extension electrode 292 may be omitted as necessary.

In addition, in the second embodiment, when the first substrate and the second substrate are bonded together, the second electrode positioned on the first substrate and the protrusion 291 of the auxiliary electrode 290 positioned on the second substrate 280 will be described differently. In addition, a problem may occur that a short circuit occurs by forming a conductive adhesive between the common electrode and the second electrode.

Third Embodiment

3 is a schematic plan view of an organic light emitting display device according to a third embodiment of the present invention. An area “PA” displayed on the second substrate 380 of FIG. 3 represents an area corresponding to a plurality of sub pixels formed on the first substrate.

The third embodiment of the present invention is similar in configuration to the first embodiment described above. However, since the structure of the auxiliary electrode is different from that of the first embodiment, only the second substrate and the auxiliary electrode will be described in order to avoid duplication of explanation.

The auxiliary electrode 390 of the organic light emitting display device according to the third embodiment may be formed in a net shape on the second substrate 380 so as to be positioned in a region between subpixels. In other words, it can be described that a net shape can be formed between the area between the scan lines to which the scan signal is supplied or between the plurality of subpixels and the corresponding area PA on the second substrate 380. .

Here, the auxiliary electrode 390 protrudes so that a part of the auxiliary electrode 390 contacts the second electrode positioned between the plurality of sub pixels formed on the first substrate as in the first embodiment. Therefore, the auxiliary electrode 390 will be briefly described as follows.

The auxiliary electrode 390 may include a metal electrode on the second substrate 380, a spacer on the metal electrode, an insulating layer on the spacer, and a common electrode on the insulating layer. The auxiliary electrode 390 may include an extension electrode 392 extending from the common electrode and positioned on the second substrate 380. The thickness of the extension electrode 392 may be thinner than the thickness of the spacer. The extension electrode 392 may be formed on the entire inner side of the bonding area SL bonded to the first substrate.

Here, the auxiliary electrode 390 shown in FIG. 3 is a metal electrode, a spacer, an insulating film in order to facilitate the separation between the extension electrode 392 and the metal electrode, spacer, insulating film, and common electrode included in the auxiliary electrode 390. And a protrusion 391 including a common electrode.

In the third embodiment, unlike the first embodiment, since the length of the metal electrode included in the protrusion 391 extends to the entire area of the second substrate 380, the common voltage supplied through the auxiliary electrode 390 is dropped. There is an effect that can further reduce the problem.

In addition, in the third embodiment, since the extension electrode 392 is formed to occupy a large area of the second substrate 380, the common voltage supplied to the second electrode is dropped, thereby reducing the display quality. You can add However, the extension electrode 392 may be omitted as necessary.

In addition, in the third embodiment, when the first substrate and the second substrate 380 are bonded to each other, the protrusion 391 of the second electrode positioned on the first substrate and the auxiliary electrode 390 positioned on the second substrate 380, In other words, a short circuit may be solved by forming a conductive adhesive between the common electrode and the second electrode.

As described above, each embodiment of the present invention prevents the drop of the common voltage supplied to the electrode by forming an auxiliary electrode in contact with the electrode on the second substrate and joining the first substrate and the second substrate, thereby preventing the luminance difference in the panel. There is an effect to provide an organic electroluminescent display device that can be solved to improve the display quality. In addition, the present invention has an effect suitable for large area panel implementation.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the technical configuration of the present invention described above may be modified in other specific forms by those skilled in the art to which the present invention pertains without changing its technical spirit or essential features. It will be appreciated that it may be practiced. Therefore, the embodiments described above are to be understood as illustrative and not restrictive in all aspects. In addition, the scope of the present invention is shown by the claims below, rather than the above detailed description. Also, it is to be construed that all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts are included in the scope of the present invention.

1A is a schematic plan view of an organic light emitting display device according to a first embodiment of the present invention;

FIG. 1B is a sectional view of the X-X region of FIG. 1A; FIG.

1C is a plan view of the second substrate shown in FIG. 1A.

1D is another cross-sectional view of the X-X region of FIG. 1A;

2 is a schematic plan view of an organic light emitting display device according to a second embodiment of the present invention;

3 is a schematic plan view of an organic light emitting display device according to a third embodiment of the present invention;

<Explanation of symbols on main parts of the drawings>

110: first substrate 120: transistor array

130: upper insulating film 140: first electrode

150: bank layer 170: second electrode

180: second substrate 190: auxiliary electrode

Claims (10)

A first substrate; A subpixel including a first electrode, a light emitting layer, and a second electrode on the first substrate and disposed in a matrix; A second substrate spaced apart from and bonded to the first substrate; And An organic light emitting display device comprising a protruding auxiliary electrode positioned on the second substrate and partially contacting the second electrode. The method of claim 1, The auxiliary electrode, To be located between the sub-pixels At least one organic light emitting display device, characterized in that formed on the second substrate. The method of claim 1, The auxiliary electrode, To be located between the sub-pixels The organic light emitting display device is formed on the second substrate in one direction. The method of claim 1, The auxiliary electrode, To be located between the sub-pixels An organic light emitting display device, characterized in that formed on the second substrate in the form of a net. The method of claim 1, The auxiliary electrode, And a metal electrode positioned on the second substrate, a spacer disposed on the metal electrode, an insulating layer disposed on the spacer, and a common electrode disposed on the insulating layer. The method of claim 5, The auxiliary electrode, An organic light emitting display device comprising: an extension electrode extending from the common electrode and positioned on the second substrate. The method of claim 6, The thickness of the extension electrode, An organic light emitting display device, characterized in that thinner than the thickness of the spacer. The method of claim 6, The extension electrode, An organic light emitting display device, characterized in that the transparent electrode has a different thickness according to the region of the second substrate. The method of claim 6, The second substrate includes a bonding area bonded to the first substrate, And the extension electrode is located in every area of the bonding area. The method of claim 1, The sub pixel is, An organic light emitting display device comprising a transistor array on the first substrate and connected to the first electrode.

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