WO2012001728A1

WO2012001728A1 - Organic el display panel, display device provided with organic el display panel, and method for manufacturing organic el display panel

Info

Publication number: WO2012001728A1
Application number: PCT/JP2010/004265
Authority: WO
Inventors: 年代健一
Original assignee: パナソニック株式会社
Priority date: 2010-06-28
Filing date: 2010-06-28
Publication date: 2012-01-05

Abstract

Disclosed is an organic EL display panel which includes: a substrate; a lower electrode (103) formed on the substrate; an auxiliary electrode (104) which is formed in a region on the substrate, said region being spaced apart from the lower electrode in the direction along the main surface of the substrate; a barrier rib (106) which is formed above the substrate, from a lower electrode side portion on the side that faces the auxiliary electrode to a predetermined position between the lower electrode and the auxiliary electrode; an organic light emitting layer (108) which is formed above the lower electrode; a charge intermediate layer (109), which is formed on the organic light emitting layer, on the barrier rib, in the region above the substrate, said region being between the auxiliary electrode and the barrier rib, and on the auxiliary electrode; and an upper electrode (110) which is formed on the charge intermediate layer. The film thickness of the auxiliary electrode is more than that of the charge intermediate layer, and the side surface of the auxiliary electrode has a region that is exposed from the charge intermediate layer in the region between the auxiliary electrode and the barrier rib, and the upper electrode is in contact with the region, which is the side surface of the auxiliary electrode, and is exposed from the charge intermediate layer.

Description

Organic EL display panel, display device including organic EL display panel, and method of manufacturing organic EL display panel

The present invention relates to an organic EL display panel, a display device including the organic EL display panel, and a method for manufacturing the organic EL display panel.

In recent years, organic EL display panels that have been researched and developed are display panels that utilize the electroluminescence phenomenon of organic materials. The panel has a structure in which an organic light emitting layer is interposed between a pair of electrodes of a lower electrode (anode) and an upper electrode (cathode).

Top emission type organic EL display panels generally use ITO (indium tin oxide) or IZO (indium zinc oxide), which are light transmissive materials, as the upper electrode. Since these are higher in resistance than Al (aluminum) used for the lower electrode, for example, the organic EL display panel causes variations in luminance due to a voltage drop at the upper electrode. Specifically, the portion (center portion of the organic EL display panel) far from the terminal is darker than the vicinity of the upper electrode terminal (end portion of the organic EL display panel). In particular, in recent years, the organic EL display panel has been increased in size, and accordingly, the variation in luminance has become remarkable.

Therefore, in an organic EL display panel, a configuration in which an auxiliary electrode for supplying voltage to the upper electrode is arranged in order to reduce variation in luminance due to a voltage drop (see, for example, Patent Document 1).

An example of the configuration of an organic EL display panel in which auxiliary electrodes are arranged will be described. FIG. 18 is a partial cross-sectional view showing an example of the configuration of the organic EL display panel 1000 in which auxiliary electrodes are arranged. As shown in FIG. 18, in the organic EL display panel 1000, a planarization layer 202 is formed on a substrate 201 on which a TFT (thin film transistor) (not shown) or the like is formed, and the planarization layer 202 is formed on the planarization layer 202. A lower electrode 203 and an auxiliary electrode 204 are formed at positions separated from each other along the surface of the activating layer 202. In the organic EL display panel 1000, the region where the lower electrode 203 is formed is the pixel portion 1000a, and the region where the auxiliary electrode 204 is formed is the non-pixel portion 1000b. A bank 206 is formed between the pixel portion 1000 a and the non-pixel portion 1000 b, and the bank 206 rides on the upper surfaces of the side electrodes of the lower electrode 203 and the auxiliary electrode 204.

In the pixel portion 1000a, in the region defined by the bank 206, a hole transport layer 207 that is a charge intermediate layer having hole transport properties, an organic light emitting layer 208, and a charge intermediate layer having electron transport properties are formed on the lower electrode 203. An electron transport layer 209 and an upper electrode 210 are sequentially stacked. The electron transport layer 209 and the upper electrode 210 are continuously formed in the adjacent non-pixel portion 1000b over the bank 206. In the non-pixel portion 1000 b, the upper electrode 210 is in contact with the upper surface portion of the auxiliary electrode 204 that is not covered by the bank 206 via the electron transport layer 209.

In the organic EL display panel 1000, the cathode 210 is covered with a sealing layer 211.

JP 2002-352963 A

By the way, the reason why the auxiliary electrode 204 is in contact with the upper electrode 210 through the electron transport layer 209 is that the electron transport layer 209 is collectively formed on the entire display panel so as not to increase the manufacturing process and the manufacturing cost. Therefore, there is no technical significance that the electron transport layer 209 is interposed between the auxiliary electrode 204 and the upper electrode 210. Rather, from the viewpoint of the role of the auxiliary electrode 204, the electron transport layer 209 formed on the auxiliary electrode 204 is unnecessary. Because the electron transport layer 209 is a high-resistance semiconductor material, the electron transport layer 209 is interposed between the auxiliary electrode 204 and the upper electrode 210, so that the space between the auxiliary electrode 204 and the upper electrode 210 is reduced. This is because the electrical resistance increases.

In order to reduce the electrical resistance between the auxiliary electrode 204 and the upper electrode 210, patterning may be performed so that the electron transport layer 209 is not formed on the auxiliary electrode 204 in the manufacturing process of the organic EL display panel. This method is not preferable because it causes an increase in cost.

The present invention eliminates the charge intermediate layer on the auxiliary electrode, that is, forms the charge intermediate layer on the entire display panel, and reduces the electric resistance when supplying voltage to the upper electrode. The purpose is to provide a panel.

In order to solve the above problems, an organic EL display panel according to an aspect of the present invention includes a substrate, a lower electrode formed on the substrate, and the substrate, which is along the main surface of the substrate. An auxiliary electrode formed in a region away from the lower electrode in a direction, and between the lower electrode and the auxiliary electrode from the side of the lower electrode on the side facing the auxiliary electrode above the substrate. A partition formed over a predetermined position, an organic light emitting layer formed above the lower electrode, a region between the auxiliary electrode and the partition on the organic light emitting layer, on the partition, and above the substrate And a charge intermediate layer formed on the auxiliary electrode, and an upper electrode formed on the charge intermediate layer, wherein the auxiliary electrode has a thickness greater than that of the charge intermediate layer, The side surface of the auxiliary electrode is between the auxiliary electrode and the partition wall. Has a region exposed from the charge intermediate layers present in the area, the upper electrode is a side of the auxiliary electrode, it was in contact with the exposed from the charge interlayer region.

In the organic EL display panel according to an aspect of the present invention, the partition wall is formed from a side portion of the lower electrode facing the auxiliary electrode to a predetermined position between the lower electrode and the auxiliary electrode. A charge intermediate layer is formed in a region between the auxiliary electrode and the partition above the substrate.

Therefore, the side surface of the auxiliary electrode is not covered with the partition wall, and the charge intermediate layer comes into contact with the side surface of the auxiliary electrode.

Further, since the auxiliary electrode is thicker than the charge intermediate layer, a region exposed from the charge intermediate layer is formed on the side surface of the auxiliary electrode, and the upper electrode is in direct contact with this region. is doing.

Since the side surface of the auxiliary electrode is in direct contact with the upper electrode without passing through the charge intermediate layer, even when a charge intermediate layer is formed on the auxiliary electrode, electric resistance when supplying a voltage to the upper electrode Can be reduced.

As described above, in the organic EL display panel according to this aspect, the upper electrode is in contact with the side surface of the auxiliary electrode, so that the charge intermediate layer formed on the auxiliary electrode is not excluded by patterning, that is, The reduction in electrical resistance can be realized without increasing the number of manufacturing steps.

1 is a block diagram schematically showing an overall configuration of a display device 1 according to a first embodiment. 1 is a partial cross-sectional view illustrating a configuration of an organic EL display panel 10 according to a first embodiment. FIG. 2 is a diagram schematically showing an arrangement relationship between an anode 103, an auxiliary electrode 104, and a bank 106 in the organic EL display panel 10 according to the first embodiment. FIG. 3 is a diagram illustrating an example of a manufacturing process of the organic EL display panel 10 according to the first embodiment. FIG. 5 is a diagram illustrating an example of a part subsequent to the process illustrated in FIG. 4 in the manufacturing process of the organic EL display panel 10 according to the first embodiment. It is a figure which shows an example of the part following the process shown in FIG. 5 among the manufacturing processes of the organic electroluminescent display panel 10 of Embodiment 1. FIG. It is a figure which shows the formation method of the cathode 110 using a sputtering method. 10 is a partial cross-sectional view showing a configuration of an organic EL display panel 10 of Modification 1-1. FIG. FIG. 10 is a partial cross-sectional view and a partially enlarged view showing a configuration of an organic EL display panel 10 of Modification 1-2. 11 is a diagram illustrating an example of a manufacturing process of the organic EL display panel 10 of Modification 1-2. FIG. FIG. 10 is a partial cross-sectional view showing a configuration of an organic EL display panel 10 of Modification 1-3. FIG. 10 is a diagram schematically showing an arrangement relationship of an anode 103, an auxiliary electrode 104, and a bank 106 in an organic EL display panel 10 of Modification 1-4. 10 is a partial cross-sectional view showing a configuration of an organic EL display panel 10 of Modification 1-4. FIG. FIG. 10 is a diagram schematically showing an arrangement relationship between an anode 103, an auxiliary electrode 104, and a bank 141 in an organic EL display panel 10 of Modification 1-5. FIG. 10 is a partial cross-sectional view showing a configuration of an organic EL display panel 10 of Modification 1-5. FIG. 11 is a partial cross-sectional view showing a configuration of an organic EL display panel 10 of Modification 1-6. 1 is an external perspective view showing an external appearance of a display device 1. FIG. It is a fragmentary sectional view showing an example of composition of organic EL display panel 1000 by which an auxiliary electrode is arranged.

[Aspect]
An organic EL display panel according to an aspect of the present invention includes a substrate, a lower electrode formed on the substrate, and the substrate on the substrate and separated from the lower electrode in a direction along the main surface of the substrate. An auxiliary electrode formed in a region, and a partition wall formed from a side of the lower electrode on the side facing the auxiliary electrode to a predetermined position between the lower electrode and the auxiliary electrode. And an organic light emitting layer formed above the lower electrode, a region on the organic light emitting layer, on the partition, a region between the auxiliary electrode and the partition above the substrate, and on the auxiliary electrode A charge intermediate layer formed on the charge intermediate layer; and an upper electrode formed on the charge intermediate layer, wherein the auxiliary electrode is thicker than the charge intermediate layer, and the side surface of the auxiliary electrode is The charge intermediate existing in the region between the electrode and the partition Has a region exposed from the upper electrode is a side of the auxiliary electrode, was in contact with the exposed from the charge interlayer region.

By the way, for example, aluminum or an aluminum alloy is suitable as a lower electrode of an organic EL display panel because of its low electric resistance. However, when the lower electrode is made of aluminum or an aluminum alloy, for example, in the manufacturing process, the lower electrode An aluminum oxide film or an aluminum alloy oxide film having a high electric resistance is formed on the side surface and surface of the film.

Therefore, as another aspect of the present invention, the auxiliary electrode is made of aluminum or an aluminum alloy, and at least a region of the side surface of the auxiliary electrode exposed from the charge intermediate layer has a side surface of the auxiliary electrode. A conductive metal oxide film that prevents oxidation may be formed.

In the organic EL display panel of this aspect, the conductive metal oxide film is formed at least in a region exposed from the charge intermediate layer on the side surface of the auxiliary electrode. With this conductive metal oxide film, oxidation of the side surface of the auxiliary electrode made of aluminum or aluminum alloy can be suppressed.

In the organic EL display panel according to this aspect, the upper electrode is in electrical contact with the side surface of the auxiliary electrode via a conductive metal oxide film formed on the side surface of the auxiliary electrode. Therefore, the electrical resistance on the side surface of the auxiliary electrode can be reduced.

Here, as another aspect of the present invention, the auxiliary electrode is made of an aluminum alloy containing at least one of nickel and cobalt, and the side surface of the auxiliary electrode has nickel included in the aluminum alloy, or A precipitate containing cobalt may be formed.

In the organic EL display panel of this embodiment, a precipitate containing nickel or cobalt contained in the aluminum alloy is formed on the side surface of the auxiliary electrode.

Here, a precipitate containing nickel or cobalt has a low electric resistance and has a characteristic that it is less likely to be oxidized than aluminum or an aluminum alloy, and also has conductivity even when oxidized.

In the organic EL display panel according to this aspect, the upper electrode is in electrical contact with the side surface of the auxiliary electrode via a precipitate containing nickel or cobalt having a low electrical resistance formed on the side surface of the auxiliary electrode. As a result, the electrical resistance on the side surface of the auxiliary electrode can be reduced.

Here, as another aspect of the present invention, the precipitate may be particles.

In the organic EL display panel of this aspect, the precipitate is a particle. Since the particles are formed on the side surface of the auxiliary electrode, the side surface of the auxiliary electrode has an uneven shape. Accordingly, the contact area between the upper electrode and the side surface of the auxiliary electrode can be increased, so that the contact resistance between the upper electrode and the side surface of the auxiliary electrode can be reduced.

Here, as another aspect of the present invention, a second charge intermediate layer is formed on the upper surface of the lower electrode and the auxiliary electrode, and the second charge intermediate layer is formed on the lower electrode and the lower electrode. It may be interposed between the organic light emitting layer and interposed between the auxiliary electrode and the charge intermediate layer on the auxiliary electrode.

At this time, the second charge intermediate layer further exists in a region between the auxiliary electrode and the partition wall, and the charge intermediate layer is formed on the second charge intermediate layer in the region, and the auxiliary charge layer is formed. The thickness of the electrode is thicker than the total thickness of the charge intermediate layer and the second charge intermediate layer, and the side surface of the auxiliary electrode is a region exposed from the stacked portion of the charge intermediate layer and the second charge intermediate layer. The upper electrode may be in contact with a side surface of the auxiliary electrode that is exposed from a stacked portion of the charge intermediate layer and the second charge intermediate layer.

In the organic EL display panel according to one aspect of the present invention, the second charge intermediate layer further exists in a region between the auxiliary electrode and the partition wall, and the second charge intermediate layer is disposed on the second charge intermediate layer in the region. The charge intermediate layer is formed.

Therefore, the charge intermediate layer and the second charge intermediate layer come into contact with the side surface of the auxiliary electrode.

In addition, since the auxiliary electrode has a thickness greater than the total thickness of the charge intermediate layer and the second charge intermediate layer, the side surface of the auxiliary electrode is separated from the charge intermediate layer and the second charge intermediate layer. An exposed area is formed, and the upper electrode is in direct contact with this area.

Since the side surface of the auxiliary electrode is in direct contact with the upper electrode without the charge intermediate layer and the second charge intermediate layer, the charge intermediate layer and the second charge intermediate layer are formed on the auxiliary electrode. In addition, it is possible to reduce electrical resistance when supplying a voltage to the upper electrode.

As described above, in the organic EL display panel according to this aspect, the upper electrode is in contact with the side surface of the auxiliary electrode. Therefore, the charge intermediate layer and the second charge intermediate layer formed on the auxiliary electrode are patterned. A reduction in electrical resistance can be realized without exclusion, that is, without increasing the number of manufacturing steps.

Here, as another aspect of the present invention, the side portion of the lower electrode on which the partition wall is formed may include an upper surface of the lower electrode within a predetermined range formed on a side surface of the lower electrode.

Here, as another aspect of the present invention, the thickness of the side surface of the auxiliary electrode exposed from the charge intermediate layer may be smaller than the thickness of the upper electrode.

In the organic EL display panel of this aspect, since the thickness of the region exposed from the charge intermediate layer on the side surface of the auxiliary electrode is smaller than the film thickness of the upper electrode, the upper electrode is formed of the auxiliary electrode. It is formed without interruption from the side surface to the upper surface.

Since the entire region exposed from the charge intermediate layer on the side surface of the auxiliary electrode is in contact with the upper electrode, the electric resistance when a voltage is supplied to the upper electrode can be further reduced.

Here, as another aspect of the present invention, the thickness of the side surface of the auxiliary electrode exposed from the charge intermediate layer may be larger than the thickness of the upper electrode.

In the organic EL display panel of this aspect, the thickness of the region exposed from the charge intermediate layer on the side surface of the auxiliary electrode is thicker than the film thickness of the upper electrode. Will contact the side surface of the auxiliary electrode. Therefore, the electrical resistance can be further reduced.

Here, as another aspect of the present invention, an inner angle formed between the side surface of the auxiliary electrode and the substrate may be 90 degrees or more.

In the organic EL display panel according to this aspect, since the inner angle formed between the side surface of the auxiliary electrode and the substrate is 90 degrees or more, the charge intermediate layer is likely to be disconnected at the side surface of the auxiliary electrode. Therefore, it becomes easy to form a region exposed from the charge intermediate layer on the side surface of the auxiliary electrode. That is, it becomes easier to bring the upper electrode into contact with the side surface of the auxiliary electrode, which is exposed from the charge intermediate layer.

Here, as another aspect of the present invention, an internal angle formed between the side surface of the partition wall and the substrate may be less than 90 degrees.

Here, as another aspect of the present invention, the auxiliary electrode may be thicker than the lower electrode.

By the way, in the organic EL display panel, the partition wall is formed from the side of the lower electrode on the side facing the auxiliary electrode to a predetermined position between the lower electrode and the auxiliary electrode. In this case, an area where the partition wall adheres to the substrate is reduced as compared with a case where the partition wall is formed so as to run on the upper surface of the side portion of the auxiliary electrode. In particular, in an organic EL display panel, there is a desire to increase the formation area of the organic light emitting layer in order to further increase the luminance, and as a result, the bonding area between the partition and the substrate is reduced, and the partition The adhesion strength to the substrate is reduced. For this reason, when the formation area of the organic light emitting layer is enlarged and the partition is formed at a predetermined position between the lower electrode and the auxiliary electrode, the partition may be peeled off from the substrate. Occurs.

Therefore, as another aspect of the present invention, a substrate, a first lower electrode formed on the substrate, and the first lower electrode on the substrate in a direction along the main surface of the substrate are separated from each other. An auxiliary electrode formed in the region, and a second lower electrode formed on the substrate and on the opposite side of the formation position of the first lower electrode with the auxiliary electrode interposed therebetween, separated from the auxiliary electrode And the side of the first lower electrode on the side facing the auxiliary electrode, the upper part of the auxiliary electrode, and the side of the second lower electrode on the side facing the auxiliary electrode. A partition formed over the first lower electrode, a first organic light emitting layer formed above the first lower electrode, a second organic light emitting layer formed above the second lower electrode, and the first organic light emitting layer A charge intermediate layer formed on the barrier ribs and on the second organic light emitting layer And an upper electrode formed on the charge intermediate layer, the partition wall having an opening for exposing a part of the auxiliary electrode on an upper surface of the partition wall. The charge intermediate layer is formed on the auxiliary electrode exposed from the opening, and the auxiliary electrode is thicker than the charge intermediate layer. The side surface of the auxiliary electrode exposed from the side has a region exposed from the charge intermediate layer, and the upper electrode may be in contact with the side surface of the auxiliary electrode and exposed from the charge intermediate layer. Good.

In the organic EL display panel of this aspect, the side of the first lower electrode facing the auxiliary electrode, the side of the first lower electrode, the upper portion of the auxiliary electrode, and the auxiliary electrode of the second lower electrode The partition formed over the side part on the opposite side is configured to have an opening.

Therefore, even when the width of the partition is reduced in order to increase the formation area of the organic light emitting layer, it is possible to suppress a decrease in the area where the partition adheres to the substrate, so that the adhesion strength of the partition to the substrate is reduced. Can be suppressed. As a result, the partition can be prevented from peeling off from the substrate.

In addition, a side surface of the auxiliary electrode exposed from the opening has a region exposed from the charge intermediate layer, and the upper electrode is in contact with a region exposed from the charge intermediate layer on the side surface of the auxiliary electrode. is doing. Therefore, it is possible to reduce the electric resistance when supplying a voltage to the upper electrode.

In this way, by adopting a configuration in which the partition wall has an opening, and the upper electrode and the side surface of the auxiliary electrode are in contact with each other in this opening portion, suppression of a decrease in the bonding area between the partition wall and the substrate, It is possible to achieve both reduction in electric resistance when supplying voltage to the upper electrode.

Here, as another aspect of the present invention, a part of the auxiliary electrode exposed by the opening is a region on the first lower electrode side of the auxiliary electrode, and the auxiliary electrode exposed from the opening A side surface of the first lower electrode side region has a region exposed from the charge intermediate layer, and the upper electrode is a side surface of the auxiliary electrode side region of the first lower electrode side, It may be in contact with the area exposed from the layer.

In the organic EL display panel according to this aspect, a part of the auxiliary electrode exposed by the opening is a region on the first lower electrode side of the auxiliary electrode. Reduction can be suppressed. Further, since the upper electrode is in contact with a side surface of the auxiliary electrode on the side of the first lower electrode and exposed from the charge intermediate layer, an electric resistance when a voltage is supplied to the upper electrode Can be reduced.

Here, as another aspect of the present invention, a part of the auxiliary electrode exposed by the opening is formed on a region of the auxiliary electrode on the first lower electrode side and on the second lower electrode side of the auxiliary electrode. Each side surface of the region on the first lower electrode side and the region on the second lower electrode side of the auxiliary electrode exposed from the opening has a region exposed from the charge intermediate layer, and The electrode may be in contact with a region exposed from the charge intermediate layer on each side surface of the region on the first lower electrode side and the region on the second lower electrode side of the auxiliary electrode.

In the organic EL display panel of this aspect, the region on the first lower electrode side and the region on the second lower electrode side of the auxiliary electrode are exposed from the opening. The side surfaces of these regions have regions exposed from the charge intermediate layer, and the upper electrodes are in contact with the exposed regions.

Since it is in direct contact with the upper electrode on both side surfaces of the auxiliary electrode, the electric resistance can be further reduced.

Here, as another aspect of the present invention, a display device including the organic EL display panel according to one aspect of the present invention may be used.

Here, as another aspect of the present invention, a first step of preparing a substrate, a second step of forming a lower electrode on the substrate, a direction on the substrate and along the main surface of the substrate A third step of forming an auxiliary electrode in a region separated from the lower electrode; and from the side of the lower electrode on the side facing the auxiliary electrode, the lower electrode and the auxiliary electrode, A fourth step of forming a partition wall in a predetermined region between the first electrode, a fifth step of forming an organic light emitting layer above the lower electrode, and on the organic light emitting layer, on the partition wall, and above the substrate. And a sixth step of forming a charge intermediate layer on the region between the auxiliary electrode and the partition and the auxiliary electrode, and a seventh step of forming an upper electrode on the charge intermediate layer, The electrode is formed to be thicker than the charge intermediate layer. A region exposed from the charge intermediate layer existing in a region between the auxiliary electrode and the partition wall is formed on a side surface of the auxiliary electrode, and the upper electrode is a side surface of the auxiliary electrode, and the charge The region exposed from the intermediate layer may be in contact.

Here, as another aspect of the present invention, the upper electrode may be formed by a sputtering method.

In the organic EL display panel of this aspect, the upper electrode is formed by sputtering. Since the sputtering method has better wraparound of the electrode material constituting the upper electrode to the side surface of the auxiliary electrode than the vacuum vapor deposition method or the plasma vapor deposition method, the upper electrode is disposed on the side surface of the auxiliary electrode. It becomes easy to deposit.

Here, as another aspect of the present invention, in the sputtering method, the upper electrode forming target member disposed opposite to the substrate is disposed on the back surface of the surface facing the substrate in the sputtering apparatus in which the substrate is disposed. In addition, a magnet member may be arranged, and sputtering may be performed while moving and scanning the magnet member with respect to the target member during the seventh step.

In the organic EL display panel of this aspect, the upper electrode is formed by performing the sputtering while moving and scanning the magnet member with respect to the target member during the sputtering in the seventh step. Therefore, the angle at which the sputtered particles are incident on the side surface of the auxiliary electrode and exposed from the charge intermediate layer is gentler than the incident angle when the magnet is not moved and scanned. As a result, the sputtered particles are likely to be incident on a side surface of the auxiliary electrode that is exposed from the charge intermediate layer, so that the sputtered particles can be more easily deposited on the side surface of the auxiliary electrode. it can.

Here, as another aspect of the present invention, the auxiliary electrode is formed of an aluminum alloy containing at least one of nickel and cobalt, and the auxiliary electrode is interposed between the third step and the fourth step. A step of forming a precipitate containing nickel or cobalt on the side surface of the auxiliary electrode by heating the auxiliary electrode may be provided.

Here, as another aspect of the present invention, a step of forming a second charge intermediate layer on the upper surface of the lower electrode and the auxiliary electrode is provided between the third step and the fourth step, In the fifth step, the organic light emitting layer is formed on the second charge intermediate layer, and in the sixth step, the charge intermediate layer is formed on the organic light emitting layer, the partition, and the auxiliary electrode. The auxiliary electrode has a thickness greater than the total thickness of the charge intermediate layer and the second charge intermediate layer, and the auxiliary electrode has a side surface in a region between the auxiliary electrode and the partition wall. A region exposed from the charge intermediate layer and the second charge intermediate layer is formed, and the upper electrode is on a side surface of the auxiliary electrode and exposed to the region exposed from the charge intermediate layer and the second charge intermediate layer. It may be in contact.

[Embodiment 1]
<Overall configuration of display device 1>
The overall configuration of the display device 1 according to the present embodiment will be described with reference to FIG. FIG. 1 is a block diagram schematically showing the overall configuration of the display device 1.

As shown in FIG. 1, the display device 1 includes an organic EL display panel 10 and a drive control unit 20 connected thereto. The organic EL display panel 10 is a top emission type organic EL display panel using an electroluminescence phenomenon of an organic material.

The drive control unit 20 includes four drive circuits 21 to 24 and a control circuit 25.

In the actual display device 1, the arrangement of the drive control unit 20 with respect to the organic EL display panel 10 is not limited to this.
<Configuration of organic EL display panel 10>
(Schematic configuration of the organic EL display panel 10)
The configuration of the organic EL display panel 10 will be described in detail. FIG. 2 is a partial cross-sectional view (cross section along AA ′ in FIG. 3) showing the configuration of the organic EL display panel 10 of the first embodiment. As shown in FIG. 2, in the organic EL display panel 10, an interlayer insulating film 102 is formed on the surface of the TFT substrate 101 on the upper side in the Z-axis direction. In the organic EL display panel 10, the pixel portion 10a and the non-pixel portion 10b exist on the XY plane (see FIGS. 1 and 3), and the anode 103 is formed on the interlayer insulating film 102 in the pixel portion 10a. The auxiliary electrode 104 is formed on the interlayer insulating film 102 in the non-pixel portion 10b. In the present embodiment, the anode 103 and the auxiliary electrode 104 are formed from the same material and have the same film thickness.

The auxiliary electrode 104 formed in the non-pixel portion 10b serves to supply a voltage to the cathode 110, and the auxiliary electrode 104 suppresses variations in luminance due to a voltage drop at the cathode 110. Further, the inner angle ang1 formed between the side surface of the auxiliary electrode 104 and the interlayer insulating film 102 is 90 degrees or more.

A hole injection layer 105 is formed on the anode 103 and the auxiliary electrode 104, on the interlayer insulating film 102, and in a region between the anode 103 and the auxiliary electrode 104.

Since the role of the hole injection layer 105 is to improve hole injection properties, from the viewpoint, the hole injection layer 105 only needs to exist on the anode 103, but does not increase the manufacturing process and manufacturing cost. In addition, the hole injection layer 105 is formed collectively on the entire panel. Therefore, as described above, the hole injection layer 105 is also formed in a region other than on the anode 103.

A bank 106 is formed between the anode 103 and the auxiliary electrode 104. In the pixel portion 10a, a hole transport layer 107, an organic light emitting layer 108, an electron transport layer 109, and a cathode 110 are formed in this order on the hole injection layer 105 defined by the bank 106.

Among these, the electron transport layer 109 and the cathode 110 are formed continuously over the upper surface of the bank 106 and also in the non-pixel portion 10b.

Since the role of the electron transport layer 109 is to enhance the electron transport property, from this point of view, the electron transport layer 109 only needs to exist on the organic light emitting layer 108, but the hole injection layer 105 is formed. As in the case, the electron transport layer 109 is collectively formed on the entire panel so as not to increase the manufacturing process and the manufacturing cost. Therefore, as described above, the electron transport layer 109 is also formed in a region other than on the organic light emitting layer 108.

Since the electron transport layer 109 and the cathode 110 are continuously formed also in the non-pixel portion 10b, the electron transport layer 109 and the cathode 111 are also formed in this order on the hole injection layer 105 formed on the upper surface of the auxiliary electrode 104. Has been.

A sealing layer 111 is formed on the cathode 110.

(Detailed configuration of organic EL display panel 10)
Next, the detailed configuration of the organic EL display panel 10 will be described focusing on the configuration of the non-pixel portion 10b.

--Formation position of bank 106--
As described above, the bank 106 is formed between the anode 103 and the auxiliary electrode 104. One end of the bank 106 rides on the upper surface of the side portion of the anode 103, whereas the other end is the auxiliary electrode. It does not reach 104 and is located between the anode 103 and the auxiliary electrode 104. Therefore, the side surface of the auxiliary electrode 104 is not covered with the bank 106.

-Arrangement of anode 103, auxiliary electrode 104, and bank 106-
The arrangement of the anode 103, the auxiliary electrode 104, and the bank 106 in the organic EL display panel 10 will be described in detail. FIG. 3 is a diagram schematically showing the arrangement relationship between the anode 103, the auxiliary electrode 104, and the bank 106 in the organic EL display panel 10. As shown in FIG. 3, in the organic EL display panel 10 according to the present embodiment, a plurality of banks 106 are formed in a line shape in the Y-axis direction (so-called line banks). In the portion corresponding to the pixel portion, the anode 103 is formed in units of pixels between the banks 106 adjacent to each other in the X-axis direction, and in the portion corresponding to the non-pixel portion, auxiliary lines are assisted between the banks 106 adjacent in the X-axis direction. An electrode 104 is formed.

In addition, one pixel (pixel) is configured by a combination of three sub-pixels adjacent in the X-axis direction, and the auxiliary electrode 104 is formed for each pixel.

In the anode 103 in the figure, a region drawn with diagonal lines is a region exposed from the bank 106, and a region drawn with broken lines is a region covered with the bank 106. As apparent from FIG. 3, the side of the anode 103 is covered with the bank 106, whereas the bank 106 does not reach the side of the auxiliary electrode 104, and the side of the auxiliary electrode 104 is 106 is not covered.

--Area between auxiliary electrode 104 and bank 106--
Returning to FIG. 2, as described above, the electron transport layer 109 and the cathode 110 are continuously formed not only in the pixel portion 10a but also in the non-pixel portion 10b. Therefore, the electron transport layer 110 and the cathode 111 are also formed in this order on the hole injection layer 105 between the bank 106 and the auxiliary electrode 104. Here, the film thickness of the auxiliary electrode 104 is larger than the total film thickness of the hole injection layer 105 and the electron transport layer 109. Therefore, the side surface of the auxiliary electrode 104 not covered by the bank 106 is in contact with the hole injection layer 105 and the electron transport layer 109, and there is a region exposed from the hole injection layer 105 and the electron transport layer 109. The cathode 110 is in contact.

Further, the thickness of the portion exposed from the hole injection layer 105 and the electron transport layer 109 on the side surface of the auxiliary electrode 104, that is, the length th1 of the exposed region in the thickness direction is thinner than the thickness of the cathode 110. The film thickness of the cathode 110 here is the film thickness of the cathode 110 formed on the electron transport layer 108 and in a flat portion (for example, the film thickness th1 in FIG. 2).

Since the film thickness of the exposed portion is thinner than the film thickness of the cathode 110, the cathode 110 is formed without interruption from the side surface to the upper surface of the auxiliary electrode 104. Therefore, all portions exposed from the hole injection layer 105 and the electron transport layer 109 on the side surface of the auxiliary electrode 104 are in contact with the cathode 110.

Further, the cathode 111 is continuously formed from the side surface to the upper surface of the auxiliary electrode 104, whereas the electron transport layer 109 is formed discontinuously from the side surface to the upper surface of the auxiliary electrode 104 (hereinafter referred to as “step break”). It is said).

According to the configuration described above, the auxiliary electrode 104 is electrically connected to the cathode 110 via the hole injection layer 105 and the electron transport layer 109 on the upper surface thereof, and at the same time, directly connected to the cathode 110 on the side surface. It is connected.

Since it is directly connected to the cathode 110 on the side surface of the auxiliary electrode 104, the electric resistance when supplying voltage to the cathode 110 can be reduced.

For example, when the width of the auxiliary electrode 104 is 20 μm, the film thickness is 200 nm, and the contact area between the auxiliary electrode 104 and the cathode 110 is 6.7E + 3 μm ² , the electrical resistance between the auxiliary electrode 104 and the cathode 110 is 2 Although it is about 0.0E + 6Ω, with the configuration shown in this embodiment mode, since the side surface of the auxiliary electrode 104 is directly connected to the cathode 110, the electrical resistance can be reduced to about 1/1000 to 1/100. .

Further, since the inner angle ang1 formed between the side surface of the auxiliary electrode 104 and the interlayer insulating film 102 is 90 degrees or more, the electron transport layer 109 is likely to be disconnected at the side surface of the auxiliary electrode 104. Therefore, it becomes easy to form a region exposed from the hole injection layer 105 and the electron transport layer 109 on the side surface of the auxiliary electrode. That is, the cathode 110 can be easily brought into contact with the side surface of the auxiliary electrode 104 and exposed from the hole injection layer 105 and the electron transport layer 109.

--Formation position of the other end of the bank 106--
The range in which the other end of the bank 106 is located between the anode 103 and the auxiliary electrode 104 will be described. First, how close the other end of the bank 106 can be in the direction of the anode 103 will be described. At least the side portion of the anode 103 needs to be covered with the bank 106. Therefore, the other end of the bank 106 can be brought close to the anode 103 within a range that satisfies the condition.

To explain how close the other end of the bank 106 can be in the direction of the auxiliary electrode 104, the other end of the bank 106 and the side surface of the auxiliary electrode 104 may be in contact with each other. However, in that case, the film thickness of the bank 106, the film thickness of the hole injection layer 105, and the total film thickness of the electron transport layer 109 to be described later are the film thickness of the auxiliary electrode 104 in the portion in contact with the side surface of the auxiliary electrode 104. It must be thinner than the thickness. This is because a region for directly contacting the cathode 110 described later is required on the side surface of the auxiliary electrode 104.

Further, the inner angle ang2 formed between the side surface at the other end of the bank 106 and the interlayer insulating film 102 is less than 90 degrees. In FIG. 2, the other end of the bank 106 is drawn with the inner angle ang2 close to 90 degrees, but it is actually about 30 to 60 degrees and is very gentle. Therefore, even if the side surface of the auxiliary electrode 104 and the other end of the bank 106 are in contact with each other, the total film thickness described above can be smaller than the film thickness of the auxiliary electrode 104.

Hereinafter, materials of each part in the organic EL display panel 10 will be described in detail.

<Configuration of each part>
The TFT substrate 101 is, for example, alkali-free glass, soda glass, non-fluorescent glass, phosphoric acid glass, boric acid glass, quartz, acrylic resin, styrene resin, polycarbonate resin, epoxy resin, polyethylene, polyester, and silicone. A TFT, a wiring member, and a passivation film (not shown) for covering the TFT are formed on a substrate body of an insulating material such as resin or alumina. The substrate body may be an organic resin film.

The interlayer insulating film 102 is provided to adjust the surface step of the TFT substrate 101 to be flat, and is made of an insulating material such as polyimide resin or acrylic resin.

The anode 103 and the auxiliary electrode 104 are made of Al (aluminum) or an aluminum alloy. The anode 103 is made of, for example, Ag (silver), an alloy of silver, palladium, and copper, an alloy of silver, rubidium, and gold, MoCr (alloy of molybdenum and chromium), NiCr (alloy of nickel and chromium), or the like. It may be formed. Since the organic EL display panel 10 according to the first embodiment is a top emission type, the anode 103 is preferably formed of a light reflective material. The width of the auxiliary electrode 104 is preferably 10-50 μm and the film thickness is preferably 50-300 nm.

The hole injection layer 105 is made of MoOx (molybdenum oxide), WOx (tungsten oxide) or MoxWyOz (molybdenum-tungsten oxide). The hole injection layer 105 only needs to be formed of a material that performs a hole injection function. Examples of such a material include metal oxide, metal nitride, and metal oxynitride. The film thickness of the hole injection layer 105 is preferably 40 nm-80 nm.

The bank 106 is made of an organic material such as resin and has an insulating property. Examples of organic materials include acrylic resins, polyimide resins, novolac type phenol resins, and the like. The bank 106 preferably has organic solvent resistance. Furthermore, since the bank 106 may be subjected to an etching process, a baking process, or the like, it is preferable that the bank 106 be formed of a highly resistant material that does not excessively deform or alter the process.

The hole transport layer 107 has a function of blocking electrons from being transported from the organic light emitting layer 108 to the hole injection layer 105, a function of efficiently transporting holes to the organic light emitting layer 108, and the like.

The hole transport layer 107 includes, for example, a triphenyldiamine derivative (TPD), a porphyrin compound such as porphine, tetraphenylporphine copper, phthalocyanine, copper phthalocyanine, titanium phthalocyanine oxide, 1,1-bis [4- (di-P -Tolylamino) phenyl] cyclohexane, 4,4 ', 4 "-trimethyltriphenylamine, N, N, N', N'-tetrakis (P-tolyl) -P-phenylenediamine, 1- (N, N-di -P-tolylamino) naphthalene, 4,4'-bis (dimethylamino) -2-2'-dimethyltriphenylmethane, N, N, N ', N'-tetraphenyl-4,4'-diaminobiphenyl, N N'-diphenyl-N, N'-di-m-tolyl-4, 4'-diaminobiphenyl, N-phenylcarbazole And stilbene compounds such as 4-di-P-tolylaminostilbene, 4- (di-P-tolylamino) -4 ′-[4- (di-P-tolylamino) styryl] stilbene, , Triazole derivatives, oxazizazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, annealed amine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives Fluorenone derivatives, hydrazone derivatives, silazane derivatives, polysilane derivatives, polysilane aniline copolymers, polymer oligomers, styrinamine compounds, aromatic dimethylidin compounds, poly-3,4 ethylene diene. Oxythio E emissions (PEDOT), tetra Hye click sill fluorenyl phenyl (TFB), or is formed using an organic material such as a polythiophene derivative such as poly-3-methylthiophene (pMET).

In addition to the above, the hole transport layer 107 can be formed by using a polymer dispersion material in which an organic material for a low molecular hole transport layer is dispersed in a polymer such as polycarbonate. Inorganic materials such as MoO ₃ , V ₂ O ₅ , WO ₃ , TiO ₂ , SiO ₂ , and MgO can also be used.

The organic light emitting layer 108 includes, for example, an oxinoid compound, a perylene compound, a coumarin compound, an azacoumarin compound, an oxazole compound, an oxadiazole compound, a perinone compound, a pyrrolopyrrole compound, a naphthalene compound, and an anthracene compound described in JP-A-5-163488. , Fluorene compounds, fluoranthene compounds, tetracene compounds, pyrene compounds, coronene compounds, quinolone compounds and azaquinolone compounds, pyrazoline derivatives and pyrazolone derivatives, rhodamine compounds, chrysene compounds, phenanthrene compounds, cyclopentadiene compounds, stilbene compounds, diphenylquinone compounds, styryl compounds , Butadiene compounds, dicyanomethylenepyran compounds, dicyanomethylenethiopyran compounds, fluorescein compounds, Lilium compound, thiapyrylium compound, serenapyrylium compound, telluropyrylium compound, aromatic aldadiene compound, oligophenylene compound, thioxanthene compound, cyanine compound, acridine compound, metal complex of 8-hydroxyquinoline compound, metal complex of 2-bipyridine compound, It is preferably formed of a fluorescent material such as a complex of a Schiff salt and a group III metal, an oxine metal complex, or a rare earth complex.

The electron transport layer 109 has a function of transporting electrons injected from the cathode 110 to the organic light emitting layer 108. For example, a nitro-substituted fluorenone derivative, a thiopyrandioxide derivative, a diphequinone described in JP-A-5-163488. Derivatives, perylene tetracarboxyl derivatives, anthraquinodimethane derivatives, fluorenylidenemethane derivatives, anthrone derivatives, oxadiazole derivatives, perinone derivatives, and quinoline complex derivatives are preferable. The film thickness of the electron transport layer 109 is preferably 20 nm-80 nm.

The cathode 110 is made of, for example, ITO (indium tin oxide) or IZO (indium zinc oxide). Since the organic EL display panel 10 is a top emission type, the cathode 110 is preferably formed of a light transmissive material. The film thickness of the cathode 110 is preferably about 100 nm.

The sealing layer 111 has a function of preventing the organic light emitting layer 108 or the like from being exposed to moisture or air, for example, SiO (silicon oxide), SiN (silicon nitride), SiON (acidic). It is made of a material such as silicon nitride), SiC (silicon carbide), SiOC (carbon-containing silicon oxide), AlN (aluminum nitride), Al2O3 (aluminum oxide). Since the organic EL display panel 10 is a top emission type, the sealing layer 111 is preferably formed of a light transmissive material.

<Manufacturing method>
Then, the manufacturing process of the organic electroluminescence display panel 10 is illustrated. FIG. 4-6 is a diagram illustrating an example of the manufacturing process of the organic EL display panel 10.

First, as shown in FIG. 4A, an interlayer insulating film 102 is formed on the TFT substrate 101.

Next, for example, an Al thin film or an aluminum alloy thin film is formed by sputtering, and the Al thin film or the aluminum alloy thin film is patterned by, for example, photolithography and etching. The auxiliary electrode 104 is formed. At that time, the anode 103 and the auxiliary electrode 104 are formed thicker than the total thickness of the hole injection layer 105 and the electron transport layer 108 to be formed in the subsequent process. In addition, due to side etching during etching, the formed auxiliary electrode 104 has an internal angle of 90 degrees or more formed between the side surface and the interlayer insulating film 102.

The Al thin film or the aluminum alloy thin film may be formed by vacuum deposition or the like.

Next, as shown in FIG. 4C, a hole injection layer 105 of WOx or MoxWyOz is formed by a technique such as vacuum deposition or sputtering using a target composition containing WOx or MoxWyOz.

Next, a film made of an insulating organic material is formed on the hole injection layer 105, and a photoresist is uniformly applied thereon. A mask having an opening (a pattern of a bank to be formed) having a predetermined shape for removing a part of the insulating organic material layer and exposing a part of the hole injection layer 105 is overlaid on the applied photoresist. . Then, it is exposed from above the mask to form a resist pattern. Thereafter, excess insulating organic material and uncured photoresist are washed out with an aqueous or non-aqueous etching solution (peeling agent). Thereby, patterning of the insulating organic material is completed. Thereafter, the photoresist (resist residue) on the patterned insulating organic material is removed by washing with pure water. Thus, the bank 106 is completed (see FIG. 4D). One end of the bank 106 rides on the anode 103 and the other end is positioned between the anode 103 and the auxiliary electrode 104.

Next, as shown in FIG. 5A, a hole transport layer 107 is formed on the anode 103 in each region partitioned by the bank 106.

Next, as shown in FIG. 5B, a composition ink (hereinafter simply referred to as “ink”) containing an organic EL material is dropped into each region partitioned by the bank 106 by, for example, an ink jet method. The organic light emitting layer 108 is formed by drying the ink. The organic light emitting layer 108 may be formed by a dispenser method, a nozzle coating method, a spin coating method, intaglio printing, letterpress printing, or the like.

Next, as shown in FIG. 5C, the electron transport layer 109 is formed by, for example, vacuum deposition. Since the inner angle of the auxiliary electrode 104 formed between the side surface and the interlayer insulating film 102 is 90 degrees or more, the electron transport layer 109 is disconnected.

Next, as shown in FIG. 6A, an ITO thin film to be the cathode 110 is formed. Here, the cathode 110 is formed, for example, by sputtering. FIG. 7 is a diagram illustrating a method of forming the cathode 110 using a sputtering method. As shown in FIG. 7, in a sputtering apparatus (not shown), a target member 122 is fixed above the substrate, and a magnet 121 is disposed on the fixed target member 122. The magnet 121 moves (scans) along the surface of the target member 122. When a voltage is applied between the target member 122 and the substrate, the ions 123 collide with the target member 122. At that time, the ions 123 are attracted to the magnet 121 and collide with a target portion under the magnet 121. Target particles ejected by the colliding ions adhere to the substrate. Some of the ejected target particles are incident in a direction perpendicular to the substrate, while others are incident in an oblique direction. That is, the particle group generated in the target portion under the magnet 121 has a predetermined incident distribution 124 with respect to the substrate. When the magnet 121 is scanned, a particle group having such an incident distribution is generated in the entire target, so that the particles are easily incident on the substrate from an oblique direction. Therefore, ITO easily adheres to the side surface of the auxiliary electrode 104.

Even when the magnet 121 is not used, the sputtering method is more likely to adhere to the side surface of the auxiliary electrode 104 due to the wraparound than the vacuum vapor deposition method or the plasma vapor deposition method, but by using the magnet 121, The incident angle of the particles with respect to the substrate becomes gentler. Therefore, the particles are more easily incident on the side surface of the auxiliary electrode 104, and the particles are more easily attached.

The scanning of the magnet 121 is repeated until the formed ITO has a predetermined film thickness.

Once the cathode 110 is formed, a sealing layer 111 is then formed on the cathode 110 as shown in FIG.

According to the method of manufacturing the organic EL display panel 10 according to the present embodiment, since the side surface of the auxiliary electrode 104 is in direct contact with the cathode 110, the hole injection layer 105 and the electron transport layer formed on the auxiliary electrode 104 are used. The electrical resistance can be reduced without eliminating 109 by patterning, that is, without increasing the number of manufacturing steps.

[Modification 1-1]
A modification in which a known conductive metal oxide film 131 is provided on the surface of the auxiliary electrode 104 will be described.

The conductive metal oxide film 131 functions as a protective layer that prevents the anode 103 and the auxiliary electrode 104 from spontaneously oxidizing immediately after the formation of the anode 103 and the auxiliary electrode 104 in the manufacturing process. The material of the conductive metal oxide film 131 may be formed of a conductive material having sufficient translucency with respect to the light generated in the organic light emitting layer 108. For example, ITO or IZO is preferable. This is because good conductivity can be obtained even if the film is formed at room temperature.

FIG. 8 is a partial cross-sectional view showing the configuration of the organic EL display panel 10 of Modification 1-1. As shown in FIG. 8, the conductive metal oxide film 131 is interposed between the anode 103 and the hole injection layer 105 and between the auxiliary electrode 104 and the hole injection layer 105 to improve the bondability. Yes. The conductive metal oxide film 131 is also formed on the side surfaces of the anode 103 and the auxiliary electrode 104 continuously from the upper surface.

Therefore, in the organic EL display panel 10 according to the modified example 1-1, the side surface of the auxiliary electrode 104 is in contact with the cathode 110 via the conductive metal oxide film 131. Since the conductive metal oxide film 131 has a lower electric resistance than an oxide of aluminum or aluminum alloy, the electric resistance on the side surface of the auxiliary electrode 104 can be further reduced.

The conductive metal oxide film 131 is formed on the interlayer insulating film 102 and also in a region where the anode 103 and the auxiliary electrode 104 are not formed, in a state of being continuous from their side surfaces.

[Modification 1-2]
A modification in which the auxiliary electrode 104 is formed of an aluminum alloy containing nickel will be described.

In this modification, nickel is deposited on at least a part of the surface of the anode 103 and the auxiliary electrode 104, and the surface of the deposited nickel is oxidized to form a nickel oxide layer.

FIG. 9 is a partial cross-sectional view and a partially enlarged view showing the configuration of the organic EL display panel 10 of Modification 1-2. In the partially enlarged view, the side surface of the auxiliary electrode 104 of the organic display panel 10 and its peripheral portion are extracted. As shown in FIG. 9, a precipitate containing nickel is formed on the surface of the side surface of the aluminum (Al) layer 1040 as the main component (deposited nickel 1041).

The deposited nickel 1041 has low electrical resistance and is less susceptible to oxidation than aluminum or an aluminum alloy, and also has conductivity even when oxidized.

Further, the deposited nickel 1041 is not deposited on the entire surface of the side surface of the auxiliary electrode 104, but is deposited on a part of the surface. A nickel oxide layer 1043 is formed on the deposited portion of the surface of the deposited nickel 1041.

Also, an aluminum oxide layer 1042 is formed on the surface of the aluminum layer 1040 where the deposited nickel 1041 does not exist.

In the organic EL display panel 10 of this modification, the cathode 110 is in electrical contact with the side surface of the auxiliary electrode 104 via the deposited nickel 1041 formed on the side surface of the auxiliary electrode 104. It is possible to further reduce the electrical resistance on the side surface.

Furthermore, the above-described deposited nickel 1041 is a particle. Since the nickel particles are formed on the side surface of the auxiliary electrode 104, the side surface of the auxiliary electrode 104 has an uneven shape. Thereby, the contact area between the cathode 110 and the side surface of the auxiliary electrode 104 can be increased, and the contact resistance between the cathode 110 and the side surface of the auxiliary electrode 104 can be reduced.

Note that the nickel oxide layer 1043 formed on the surface of the deposited nickel 1041 has a hole injection property, and the anode 103 has a hole injection property. Therefore, in this modification, the hole injection layer is not separately formed.

The fact that the nickel oxide layer 1043, which is an oxide layer of a transition metal, has hole injecting properties has also been confirmed in the following references.

(Reference) “Enhanced hole injections in organic light-emitting devices by developing nickel oxide on indium tin oxide nano, I-Min Chan, Tsun Y. Hong, “2002 American Institute of Physics, Applied Physics Letters, volume 81, number 10”.
Even when the auxiliary electrode 104 is formed of an aluminum alloy containing cobalt, the same effects as described above can be obtained.

<Manufacturing method>
Then, the manufacturing process of the organic electroluminescence display panel 10 of this modification is illustrated. FIG. 10 is a diagram illustrating an example of a manufacturing process of the organic EL display panel 10 of the present modification. 10 (a) and 10 (b) are the same as FIGS. 4 (a) and 4 (b), and the description thereof is omitted here.

After the anode 103 and the auxiliary electrode 104 are formed, the anode 103 and the auxiliary electrode 104 are baked in an oxygen atmosphere. The firing conditions were a firing temperature of 230 [° C.] or higher and a firing time of 30 [min. ] That's it. By firing the anode 103 and the auxiliary electrode 104 in this way, nickel is deposited on a part of the surface of the aluminum layer 1041 (deposited nickel 1042), as shown in the partially enlarged view of FIG. The surface of the nickel 1042 is oxidized to form a nickel oxide layer 1044. Further, the surface of the aluminum layer 1041 is also oxidized to form an aluminum oxide layer 1043, and the fired anode 103 and auxiliary electrode 104 are completed.

[Modification 1-3]
A modification in which the auxiliary electrode 104 is formed thicker than the anode 103 will be described. FIG. 11 is a partial cross-sectional view showing the configuration of the organic EL display panel 10 of Modification 1-3. As shown in FIG. 11, the auxiliary electrode 104 is formed thicker than the anode 103. Thereby, since the contact area with the cathode 110 can be increased on the side surface of the auxiliary electrode 104, the electrical resistance can be further reduced.

[Modification 1-4]
FIG. 12 is a diagram schematically illustrating an arrangement relationship of the anode 103, the auxiliary electrode 104, and the bank 106 in the organic EL display panel 10 of Modification 1-4. As shown in FIG. 12, in the organic EL display panel 10 of Modification 1-4, a plurality of banks 106 are formed in a line shape in the Y-axis direction, and a bank adjacent to the X-axis direction in a portion corresponding to the pixel portion. The anode 103 is formed between the pixels 106 in units of pixels, and the auxiliary electrode 104 is formed in a line shape in a portion corresponding to the non-pixel portion. These points are the same as in FIG. However, in the organic EL display panel 10 according to the present modification, as shown in FIG. 12, the bank 106 in the portion corresponding to the non-pixel portion has a plurality of openings at the top, and each opening has a plurality of openings. A part of the auxiliary electrode 104 is exposed. In the auxiliary electrode 104 in the figure, a region drawn with diagonal lines indicates a region exposed from the bank 106, and a region drawn with broken lines shows a region covered with the bank 106. As apparent from FIG. 12, in the auxiliary electrode 104 exposed from each opening, the bank runs on the upper surface of one side, whereas the bank 106 does not reach the other side, These sides are not covered by the bank 106.

Here, in the auxiliary electrode 104 exposed from each opening, it is not unified which side upper surface of the auxiliary electrode 104 is on the bank, but the bank 106 is on the upper surface of one side. It may be a configuration.

Further, the opening 106 adjacent in the Y-axis direction is covered with the bank 106.

Subsequently, FIG. 13 is a partial cross-sectional view (B-B ′ cross-section of FIG. 3) showing the configuration of the organic EL display panel 10 of Modification 1-4. Here, the difference from FIG. 2 will be mainly described. As shown in FIG. 13, in the organic EL display panel 10 of Modification 1-4, a bank 106 rides on the upper surface of one side of the auxiliary electrode 104. Accordingly, the side face on which the bank 106 rides cannot directly contact the cathode 110. However, since the bank 106 rides on the upper surface of one side of the auxiliary electrode 104, the contact area between the bank 106 and the hole injection layer 105 can be increased.

Therefore, for example, even when the width of the bank 106 is narrowed in the X-axis direction in order to increase the formation area of the organic light emitting layer 108, it is possible to suppress a decrease in the area where the bank 106 adheres to the hole injection layer 105. As a result, a decrease in the adhesion strength of the bank 106 to the hole injection layer 105 can be suppressed, so that the bank 106 can be prevented from peeling from the hole injection layer 105.

On the other hand, the side surface on which the bank 106 is not mounted has a region exposed from the hole injection layer 105 and the electron transport layer 109 as described above, and thus directly contacts the cathode 110 in the region. can do.

As described above, compared with the case where the both sides of the auxiliary electrode 104 are in direct contact with the cathode 110, the structure is in contact with the cathode 110 on one side, so the electrical resistance increases, but the width of the bank 106 is increased. be able to.

Therefore, it is possible to achieve both the suppression of the decrease in the bonding area between the bank 106 and the hole injection layer 105 and the reduction in the electric resistance when supplying a voltage to the cathode 110.

[Modification 1-5]
Next, a modification in which the form of the bank 106 is different will be described.

FIG. 14 is a diagram schematically showing the arrangement relationship of the anode 103, the auxiliary electrode 104, and the bank 141 in the organic EL display panel 10 of Modification 1-5.

As shown in FIG. 14, the bank 141 of the organic EL display panel 10 according to this modification has a so-called pixel in which a portion 141a extending in the X-axis direction and a portion 141b extending in the Y-axis direction are integrally formed. It is a bank. In the organic EL display panel 10 according to this modification, subpixels adjacent in the X-axis direction are partitioned by a portion 141b, and subpixels adjacent in the Y-axis direction are partitioned by a portion 141a. An anode 103 is formed in each region defined by the portion 141a and the portion 141b. In the portion corresponding to the non-pixel portion, the auxiliary electrode 104 is formed in a line shape for each pixel. In order to correspond to the auxiliary electrode 104, the bank 141b has a plurality of openings at the top of each pixel, and a part of the auxiliary electrode 104 is exposed from each opening. In the auxiliary electrode 104 in FIG. 14, similarly to FIG. 12, the hatched area indicates the area exposed from the bank 106, and the broken line area is covered by the bank 106. Is shown. As is apparent from FIG. 14, the auxiliary electrode 104 exposed from the intersection of the portion 141a and the portion 141b does not reach the sides 141b and is not covered with the portion 141b.

On the other hand, both sides of the auxiliary electrode 104 exposed from the portion 141a between the anodes 103 are covered with the portion 141a.

Subsequently, FIG. 15 is a partial cross-sectional view (cross-section C-C ′ of FIG. 14) showing the configuration of the organic EL display panel 10 of Modification 1-5. As shown in FIG. 15, both side surfaces of the auxiliary electrode 104 are exposed without being covered by the bank 106, and the exposed both side surfaces have regions exposed from the hole injection layer 105 and the electron transport layer 108. is doing. In that region, the cathode 110 is in direct contact.

14, both sides of the auxiliary electrode 104 exposed from the portion 141a between the anodes 103 are covered with the portion 141a, whereas the auxiliary electrode 104 exposed from the intersection of the portion 141a and the portion 141b in FIG. Both side surfaces are exposed and are in direct contact with the cathode 110.

[Modification 1-6]
A modification in which the thickness of the region exposed from the hole injection layer 105 and the electron transport layer 108 on the side surface of the auxiliary electrode 104 is thicker than the thickness of the cathode 110 will be described.

FIG. 16 is a partial cross-sectional view showing the configuration of the organic EL display panel 10 of Modification 1-6. As shown in FIG. 16, the thickness th3 of the region exposed from the hole injection layer 105 and the electron transport layer 108 on the side surface of the auxiliary electrode 104 is thicker than the film thickness th4 of the cathode 110.

For this reason, the entire thickness of the cathode 110 is in contact with the side surface of the auxiliary electrode 104. Therefore, the electrical resistance can be further reduced.
(Supplement)
As described above, the organic EL display panel 10 according to the present invention has been described based on the embodiment, but the present invention is not limited to the above embodiment.
(1) In the above embodiment, MoOx, WOx or MoxWyOz is used as the material constituting the hole injection layer 105. However, even when a metal other than Mo (molybdenum) or W (tungsten) is used, the present embodiment is used. By applying the embodiment, a similar effect can be obtained.
(2) Although the external appearance of the display device 1 is not shown in the above embodiment, for example, it may have an external appearance as shown in FIG.
(3) In the above embodiment, the side portion of the anode 103 on which the bank 106 is formed is a region including the upper surface of the anode 103 within a predetermined range formed on the side surface of the anode 103. Here, the predetermined range will be described. There is no particular limitation on the center direction of the anode 103. However, from the viewpoint of securing the formation area of the organic light emitting layer 108, it is desirable that the area of the bank 106 formed on the upper surface of the anode 103 is as small as possible. In the side direction of the anode 103, the formation position of the bank 106 can be brought closer to the side direction of the anode 103 as long as the side surfaces of the anode 103 and the hole injection layer 105 are not exposed. However, considering the accuracy of photolithography, it is desirable to form the bank 106 at a position where it is guaranteed that the side surfaces of the anode 103 and the hole injection layer 105 are not exposed even if the formation position is shifted.
(4) In the above modified example 1-4, the bank 106 rides on the upper surface of one side of the auxiliary electrode 104, and the other side is not covered with the bank 106. A configuration in which both sides are not covered by the bank 106 may be employed. Thereby, electrical resistance can be further reduced.
(5) The above embodiment and the above modifications may be combined.

The present invention can be used, for example, for home or public facilities, various display devices for business use, television devices, displays for portable electronic devices, and the like.

DESCRIPTION OF SYMBOLS 1 Display apparatus 10 Organic EL display panel 20 Drive control part 21-24 Drive circuit 25 Control circuit 101 TFT substrate 102 Interlayer insulation film 103 Anode 104 Auxiliary electrode 105 Hole injection layer 106 Bank 107 Hole transport layer 108 Organic light emitting layer 109 Electron transport layer 110 Cathode 111 Sealing layer

Claims

A substrate,
A lower electrode formed on the substrate;
An auxiliary electrode formed on the substrate and in a region separated from the lower electrode in a direction along the main surface of the substrate;
A partition formed above the substrate and from a side of the lower electrode facing the auxiliary electrode to a predetermined position between the lower electrode and the auxiliary electrode;
An organic light emitting layer formed above the lower electrode;
A charge intermediate layer formed on the organic light emitting layer, on the barrier ribs, above the substrate, between the auxiliary electrode and the barrier ribs, and on the auxiliary electrode;
An upper electrode formed on the charge intermediate layer,
The auxiliary electrode is thicker than the charge intermediate layer,
The side surface of the auxiliary electrode has a region exposed from the charge intermediate layer present in a region between the auxiliary electrode and the partition wall,
The organic EL display panel, wherein the upper electrode is in contact with a region exposed from the charge intermediate layer on a side surface of the auxiliary electrode.
The auxiliary electrode is made of aluminum or an aluminum alloy,
The organic EL display according to claim 1, wherein a conductive metal oxide film that prevents oxidation of the side surface of the auxiliary electrode is formed at least in a region exposed from the charge intermediate layer on the side surface of the auxiliary electrode. panel.
The auxiliary electrode is made of an aluminum alloy containing at least one of nickel and cobalt,
The organic EL display panel according to claim 1, wherein a precipitate containing nickel or cobalt contained in the aluminum alloy is formed on a side surface of the auxiliary electrode.
The organic EL display panel according to claim 3, wherein the precipitate is a particle.
A second charge intermediate layer is formed on upper surfaces of the lower electrode and the auxiliary electrode;
The second charge intermediate layer is interposed between the lower electrode and the organic light emitting layer on the lower electrode,
The organic EL display panel according to any one of claims 1 to 4, wherein the organic EL display panel is interposed between the auxiliary electrode and the charge intermediate layer on the auxiliary electrode.
The second charge intermediate layer is further present in a region between the auxiliary electrode and the partition wall, and the charge intermediate layer is formed on the second charge intermediate layer in the region,
The auxiliary electrode is thicker than the total thickness of the charge intermediate layer and the second charge intermediate layer,
The side surface of the auxiliary electrode has a region exposed from a stacked portion of the charge intermediate layer and the second charge intermediate layer,
The organic EL display panel according to claim 5, wherein the upper electrode is in contact with a side surface of the auxiliary electrode, which is exposed from a stacked portion of the charge intermediate layer and the second charge intermediate layer.
The organic EL display according to any one of claims 1 to 5, wherein a side portion of the lower electrode on which the partition wall is formed includes an upper surface of the lower electrode within a predetermined range formed on a side surface of the lower electrode. panel.
The organic EL display panel according to any one of claims 1 to 7, wherein a thickness of a region exposed from the charge intermediate layer on a side surface of the auxiliary electrode is thinner than a film thickness of the upper electrode.
The organic EL display panel according to any one of claims 1 to 7, wherein a thickness of a region exposed from the charge intermediate layer on a side surface of the auxiliary electrode is thicker than a film thickness of the upper electrode.
The organic EL display panel according to any one of claims 1 to 9, wherein an inner angle formed between a side surface of the auxiliary electrode and the substrate is 90 degrees or more.
The organic EL display panel according to any one of claims 1 to 10, wherein an inner angle formed by a side surface of the partition wall and the substrate is less than 90 degrees.
The organic EL display panel according to claim 1, wherein a film thickness of the auxiliary electrode is larger than a film thickness of the lower electrode.
A substrate,
A first lower electrode formed on the substrate;
An auxiliary electrode formed on the substrate and in a region separated from the first lower electrode in a direction along the main surface of the substrate;
A second lower electrode formed on the substrate opposite to the formation position of the first lower electrode across the auxiliary electrode and spaced from the auxiliary electrode;
Formed over the substrate and on the side of the first lower electrode facing the auxiliary electrode, the upper part of the auxiliary electrode, and the side of the second lower electrode facing the auxiliary electrode A partition wall,
A first organic light emitting layer formed above the first lower electrode;
A second organic light emitting layer formed above the second lower electrode;
A charge intermediate layer formed on the first organic light emitting layer, on the partition, and on the second organic light emitting layer;
An upper electrode formed on the charge intermediate layer,
The barrier rib has an opening exposing a part of the auxiliary electrode on the upper surface of the barrier rib,
A portion of the exposed auxiliary electrode includes at least a side surface thereof;
The charge intermediate layer is formed on the auxiliary electrode exposed from the opening,
The auxiliary electrode is thicker than the charge intermediate layer,
The side surface of the auxiliary electrode exposed from the opening has a region exposed from the charge intermediate layer,
The organic EL display panel, wherein the upper electrode is in contact with a side surface of the auxiliary electrode that is exposed from the charge intermediate layer.
A part of the auxiliary electrode exposed by the opening is a region on the first lower electrode side of the auxiliary electrode,
The side surface of the region on the first lower electrode side of the auxiliary electrode exposed from the opening has a region exposed from the charge intermediate layer,
The organic EL display panel according to claim 13, wherein the upper electrode is in contact with a side surface of a region of the auxiliary electrode on the first lower electrode side and exposed from the charge intermediate layer.
A part of the auxiliary electrode exposed by the opening is a region on the first lower electrode side of the auxiliary electrode and a region on the second lower electrode side of the auxiliary electrode,
Each side surface of the region on the first lower electrode side and the region on the second lower electrode side of the auxiliary electrode exposed from the opening has a region exposed from the charge intermediate layer,
The upper electrode is in contact with a region exposed from the charge intermediate layer on each side surface of the region on the first lower electrode side and the region on the second lower electrode side of the auxiliary electrode. Organic EL display panel.
A display device comprising the organic EL display panel according to any one of claims 1 to 15.
A first step of preparing a substrate;
A second step of forming a lower electrode on the substrate;
A third step of forming an auxiliary electrode on the substrate in a region separated from the lower electrode in a direction along the main surface of the substrate;
A fourth step of forming a partition wall in a region extending from the side of the lower electrode facing the auxiliary electrode to a predetermined position between the lower electrode and the auxiliary electrode, above the substrate;
A fifth step of forming an organic light emitting layer above the lower electrode;
A sixth step of forming a charge intermediate layer on the organic light emitting layer, on the partition, above the substrate, between the auxiliary electrode and the partition, and on the auxiliary electrode;
A seventh step of forming an upper electrode on the charge intermediate layer,
The auxiliary electrode is formed to have a film thickness that is greater than the planned film thickness of the charge intermediate layer,
A region exposed from the charge intermediate layer present in a region between the auxiliary electrode and the partition is formed on a side surface of the auxiliary electrode,
The method for manufacturing an organic EL display panel, wherein the upper electrode is in contact with a region exposed from the charge intermediate layer on a side surface of the auxiliary electrode.
The method for manufacturing an organic EL display panel according to claim 17, wherein the upper electrode is formed by a sputtering method.
In the sputtering method,
In the sputtering apparatus for arranging the substrate, a magnet member is arranged on the back surface of the upper electrode forming target member arranged to face the substrate, the surface facing the substrate,
The method of manufacturing an organic EL display panel according to claim 18, wherein sputtering is performed while moving and scanning the magnet member with respect to the target member during the seventh step.
The auxiliary electrode is formed of an aluminum alloy containing at least one of nickel and cobalt,
The organic EL according to claim 17, wherein a step of forming a precipitate containing nickel or cobalt on a side surface of the auxiliary electrode by heating the auxiliary electrode is provided between the third step and the fourth step. Manufacturing method of display panel.
A step of forming a second charge intermediate layer on the upper surface of the lower electrode and the auxiliary electrode between the third step and the fourth step;
In the fifth step, the organic light emitting layer is formed on the second charge intermediate layer,
In the sixth step, the charge intermediate layer is formed on the organic light emitting layer, on the partition, and on the auxiliary electrode,
The auxiliary electrode is formed to be thicker than the total thickness of the charge intermediate layer and the second charge intermediate layer,
On the side surface of the auxiliary electrode, a region exposed from the charge intermediate layer and the second charge intermediate layer present in a region between the auxiliary electrode and the partition is formed,
The organic material according to any one of claims 17 to 20, wherein the upper electrode is in contact with a region exposed from the charge intermediate layer and the second charge intermediate layer on a side surface of the auxiliary electrode. Manufacturing method of EL display panel.