JP2018181460A - Organic EL Display Panel and Method of Manufacturing Organic EL Display Panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic EL display panel which realizes low resistance of a common electrode, improves luminous efficiency and suppresses luminance unevenness. SOLUTION: A first auxiliary electrode layer 135 containing a first metal (for example, tungsten) as a main component is formed above a substrate 100x, and a second metal (for example, for example) is formed on an upper layer of the first auxiliary electrode layer 135. The second auxiliary electrode layer 200 containing (aluminum alloy) as a main component is formed. The surface area of the first auxiliary electrode layer 135 is larger than the surface area of the second auxiliary electrode layer 200. Further, the resistance of the surface layer of the second auxiliary electrode layer 200 is larger than the resistance of the surface layer of the first auxiliary electrode layer 135. The common electrode layer 125 comes into contact with the first auxiliary electrode layer 135 (excluding the portion on which the second auxiliary electrode layer 200 is formed) and the second auxiliary electrode layer 200. [Selection diagram] Fig. 5

Description

  The present disclosure relates to an organic EL display panel using an organic EL (Electro Luminescence) element utilizing an electroluminescence phenomenon of an organic material, and a method of manufacturing the same.

In recent years, as a display panel used for a display device such as a digital television, an organic EL display panel in which a plurality of organic EL elements are arranged in a matrix on a substrate has been put to practical use.
In the organic EL display panel, generally, the light emitting layer of each organic EL element and the adjacent organic EL element are separated by an insulating layer made of an insulating material. In an organic EL display panel for color display, organic EL elements form sub-pixels emitting light of each color of RGB, and adjacent RGB sub-pixels are combined to form a unit pixel in color display.

The organic EL element has a basic structure in which a light emitting layer containing an organic light emitting material is disposed between a pair of electrodes, and when driven, a voltage is applied between the pair of electrodes and holes injected into the light emitting layer Emits light as it recombines with the electron.
The top emission type organic EL element has an element structure in which a pixel electrode, an organic layer (including a light emitting layer) and a common electrode layer are sequentially provided on a substrate. The light from the light emitting layer is reflected by the pixel electrode made of the light reflective material, and is emitted upward from the common electrode layer made of the light transmissive material.

The common electrode layer described above is often deposited over the entire surface of the substrate, and when the electrical resistance of the common electrode layer is large, the voltage is not sufficiently supplied due to the voltage drop in the portion far from the power supply portion. Uneven luminance may occur due to this.
Then, the method of providing an auxiliary electrode for the resistance reduction of a common electrode layer is proposed (for example, patent document 1). According to Patent Document 1, the auxiliary electrode layer is formed in the same layer as the pixel electrode, and the auxiliary electrode layer is electrically connected to the common electrode layer while being electrically insulated from the pixel electrode.

JP 2002-318556 A JP-A-5-163488

However, when a metal such as aluminum, copper, silver or the like is used for the auxiliary electrode layer, an oxide film is formed on the surface of the auxiliary electrode layer, and the formed oxide film forms an electrical resistance between the auxiliary electrode layer and the common electrode layer. There is a problem that
The present disclosure solves the above problems, reduces the electrical resistance in the electrical connection between the common electrode layer and the auxiliary electrode layer, improves the light emission efficiency, and suppresses the luminance unevenness, and the organic EL display panel An object of the present invention is to provide a manufacturing method suitable for manufacturing an EL display panel.

  In order to achieve this object, in the organic EL display panel according to one aspect of the present disclosure, a plurality of pixel electrodes are arranged in a matrix on a substrate, and a light emitting layer including an organic light emitting material is arranged on each pixel electrode. An organic EL display panel comprising: a substrate; a plurality of pixel electrodes arranged in a matrix above the substrate; and a gap of at least one of the gaps between the adjacent pixel electrodes above the substrate. A first feeding auxiliary electrode layer extending in a row or row direction, and a partial region on the first feeding auxiliary electrode layer extending in the same direction as the first feeding auxiliary electrode layer A second power feeding auxiliary electrode layer, a plurality of light emitting layers disposed on the plurality of pixel electrodes, an upper surface excluding the partial region of the first power feeding auxiliary electrode layer above the plurality of light emitting layers, and A common electrode disposed continuously covering the upper surface of the second feeding auxiliary electrode layer And the first power feeding auxiliary electrode layer mainly contains a first metal, and the second power feeding auxiliary electrode layer mainly contains a second metal different from the first metal. The resistance of the surface layer of the second power supply auxiliary electrode layer is higher than the resistance of the surface layer of the first power supply auxiliary electrode layer.

  The organic EL display panel according to an aspect of the present disclosure can reduce the electrical resistance in the electrical connection between the common electrode layer and the auxiliary electrode layer, improve the light emission efficiency, and suppress the luminance unevenness.

FIG. 1 is a schematic block diagram showing a circuit configuration of an organic EL display device 1 according to an embodiment. FIG. 5 is a schematic circuit diagram showing a circuit configuration in each sub-pixel 100se of the organic EL display panel 10 used for the organic EL display device 1. FIG. 2 is a schematic plan view showing a part of the organic EL display panel 10; It is a schematic cross section cut | disconnected by A1-A1 in FIG. It is an enlarged view of the 2nd auxiliary electrode layer 200 periphery shown in FIG. (A), (b) shows the state in each process in manufacture of the organic electroluminescent display panel 10. FIG. It is a schematic cross section cut | disconnected by A1-A1 in FIG. (C) and (d) show the state of each step in the manufacture of the organic EL display panel 10. It is a schematic cross section cut | disconnected by A2-A2 in FIG. (A)-(d) shows the state in each process in manufacture of the organic electroluminescent display panel 10. FIG. It is a schematic cross section cut | disconnected by A1-A1 in FIG. (A)-(d) shows the state in each process in manufacture of the organic electroluminescent display panel 10. FIG. It is a schematic cross section cut | disconnected by A1-A1 in FIG. (A)-(g) show the state in each process in manufacture of the organic electroluminescence display panel 10. FIG. It is a schematic cross section cut | disconnected by A1-A1 in FIG. (A)-(b) shows the state in each process in manufacture of the organic electroluminescent display panel 10. FIG. It is a schematic cross section cut | disconnected by A1-A1 in FIG. FIG. 16 is a schematic view showing a sputtering apparatus 600 used for manufacturing the common electrode layer 125.

<< Summary of Embodiment for Carrying Out the Invention >>
The organic EL display panel according to the aspect of the present disclosure is an organic EL display panel in which a plurality of pixel electrodes are arranged in a matrix on a substrate, and a light emitting layer containing an organic light emitting material is arranged on each pixel electrode. And extends in a row or row direction within at least one of the gaps between the adjacent pixel electrodes, the substrate, the plurality of pixel electrodes arranged in a matrix above the substrate, and the gap above the substrate. A first feeding auxiliary electrode layer disposed in a second direction, and a second feeding auxiliary electrode layer extended in the same direction as the first feeding auxiliary electrode layer in a partial region on the first feed auxiliary electrode layer; A plurality of light emitting layers disposed on the plurality of pixel electrodes, an upper surface of the plurality of light emitting layers, an upper surface excluding the partial region of the first power feeding auxiliary electrode layer, and the second power feeding auxiliary electrode layer And a common electrode layer disposed continuously over the upper surface, The auxiliary electrode layer mainly contains a first metal, and the second power feeding auxiliary electrode layer mainly contains a second metal different from the first metal, and the second power feeding auxiliary electrode layer The surface layer resistance is higher than the surface layer resistance of the first feeding auxiliary electrode layer.

With this configuration, it is possible to reduce the electrical resistance in the electrical connection between the common electrode layer and the auxiliary electrode layer, to improve the light emission efficiency and to suppress the luminance unevenness.
Here, a metal oxide film may be formed on the surface layer of the second power feeding auxiliary electrode layer.
Further, the sheet resistance of the first power feeding auxiliary electrode layer may be higher than the sheet resistance of the second power feeding auxiliary electrode layer.

Further, the contact resistance between the first feed auxiliary electrode layer and the common electrode layer may be lower than the contact resistance between the second feed auxiliary electrode layer and the common electrode layer.
Further, the surface area of the first power feeding auxiliary electrode layer may be larger than the surface area of the second power feeding auxiliary electrode layer.
The first metal may be tungsten or molybdenum, and the second metal may be aluminum.

  Further, in the method of manufacturing an organic EL display panel according to the aspect of the present disclosure, an organic EL formed by arranging a plurality of pixel electrodes in a matrix on a substrate and arranging a light emitting layer containing an organic light emitting material on each pixel electrode. A method of manufacturing a display panel, comprising the steps of: forming a plurality of pixel electrodes arranged in a matrix above the substrate by a vapor deposition method; and, of the gaps of the adjacent pixel electrodes above the substrate Forming a first feed auxiliary electrode layer extending in the column or row direction in at least one of the gaps by vapor deposition, and forming the first feed auxiliary electrode layer on a part of the first feed auxiliary electrode layer; (1) forming a second feeding auxiliary electrode layer, which is extended in the same direction as the feeding auxiliary electrode layer, by vapor deposition, and forming a plurality of light emitting layers on the plurality of pixel electrodes by a wet film formation method And the first step above the plurality of light emitting layers, Forming a common electrode layer continuously by a sputtering method or a CVD (Chemical Vapor Deposition) method covering the upper surface excluding the partial region of the auxiliary electrode layer and the upper surface of the second power supply auxiliary electrode layer; Including.

According to this method, it is possible to manufacture an organic EL display panel capable of reducing the electric resistance in the electrical connection between the common electrode layer and the auxiliary electrode layer, improving the light emission efficiency and suppressing the unevenness in luminance.
Embodiment 1
1.1 Circuit Configuration of Display Device 1 Hereinafter, the circuit configuration of the organic EL display device 1 (hereinafter, referred to as “display device 1”) according to the first embodiment will be described with reference to FIG.

As shown in FIG. 1, the display device 1 is configured to include an organic EL display panel 10 (hereinafter referred to as “display panel 10”) and a drive control circuit unit 20 connected thereto.
The display panel 10 is an organic EL (Electro Luminescence) panel utilizing an electroluminescence phenomenon of an organic material, and a plurality of organic EL elements are arranged and configured in, for example, a matrix. The drive control circuit unit 20 is configured of four drive circuits 21 to 24 and a control circuit 25.

In the display device 1, the arrangement of the circuits of the drive control circuit unit 20 with respect to the display panel 10 is not limited to the one shown in FIG. 1.
1.2 Circuit Configuration of Display Panel 10 In the display panel 10, a plurality of unit pixels 100e are arranged in a matrix to form a display area. Each unit pixel 100e is composed of three organic EL elements, that is, three subpixels 100se that issue three colors of R (red), G (green), and B (blue). The circuit configuration of each sub-pixel 100se will be described with reference to FIG.

FIG. 2 is a circuit diagram showing a circuit configuration of the organic EL element 100 corresponding to each sub-pixel 100se of the display panel 10 used for the display device 1.
As shown in FIG. 2, in the display panel 10 according to the present embodiment, each subpixel 100se includes two transistors Tr1 and Tr2, one capacitor C, and an organic EL element portion EL as a light emitting portion. It is done. The transistor Tr1 is a drive transistor, and the transistor Tr2 is a switching transistor.

The gate G2 of the switching transistor Tr2 is connected to the scan line Vscn, and the source S2 is connected to the data line Vdat. The drain D2 of the switching transistor Tr2 is connected to the gate G1 of the drive transistor Tr1.
The drain D1 of the drive transistor Tr1 is connected to the power supply line Va, and the source S1 is connected to the pixel electrode (anode) of the organic EL element unit EL. The common electrode layer (cathode) in the organic EL element unit EL is connected to the ground line Vcat. Further, a first auxiliary electrode layer 135 and a second auxiliary electrode layer 200 described later are also connected to the ground line Vcat, and the common electrode layer, the first auxiliary electrode layer 135 and the second auxiliary electrode layer 200 are mutually connected. There is.

The first end of the capacitor C is connected to the drain D2 of the switching transistor Tr2 and the gate G1 of the drive transistor Tr1, and the second end of the capacitor C is connected to the power supply line Va.
In the display panel 10, a plurality of adjacent sub-pixels 100se (for example, three sub-pixels 100se of emission colors of red (R), green (G) and blue (B)) are combined to form one unit pixel 100e. The unit pixels 100 e are arranged to be distributed to constitute a pixel area. Then, gate lines are respectively drawn from the gates G 2 of the respective sub-pixels 100 se and connected to the scanning lines Vscn connected from the outside of the display panel 10. Similarly, a source line is drawn from the source S2 of each sub-pixel 100se and connected to a data line Vdat connected from the outside of the display panel 10.

Further, the power supply line Va of each sub-pixel 100se and the ground line Vcat of each sub-pixel 100se are integrated and connected to the power supply line and the ground line of the display device 1.
1.3 Overall Configuration of Display Panel 10 The display panel 10 according to the present embodiment will be described using the drawings. The drawings are schematic diagrams, and the scale may be different from the actual one.

FIG. 3 is a schematic plan view showing a part of the display panel according to the embodiment.
The display panel 10 is an organic EL display panel utilizing an electroluminescence phenomenon of an organic compound, and a plurality of organic ELs arranged in a matrix on a substrate 100x (TFT substrate) on which thin film transistors (TFT: Thin Film Transistor) are formed. The element 100 has a top emission type configuration that emits light from the top surface. Here, in the present specification, the X direction, the Y direction, and the Z direction in FIG. 3 are taken as the row direction, the column direction, and the thickness direction in the display panel 10, respectively.

  In the display area of the display panel 10, unit pixels 100e composed of a plurality of organic EL elements 100 are arranged in a matrix. In each unit pixel 100e, 100aR emitting red light, 100aG emitting green light, and 100aB emitting blue light, which are regions emitting light by an organic compound (hereinafter, 100aR, 100aG, and 100aB are not distinguished from each other, “100a The three types of self-light emitting regions 100a are formed. That is, three sub-pixels 100se corresponding to the respective self-emission areas 100aR, 100aG, and 100aB arranged in the row direction (hereinafter, “blue sub-pixel 100seB”, “green sub-pixel 100seG”, and “red The pixel 100seR ′ ′ is one set to constitute a unit pixel 100e in color display.

  In the display panel 10, a plurality of auxiliary pixel electrodes 150 (FIG. 4) and a plurality of pixel electrodes 119 are arranged in a matrix on the substrate 100x at predetermined distances in the row and column directions. The plurality of auxiliary pixel electrodes 150 and the pixel electrode 119 have a rectangular shape in plan view, and are made of a light reflecting material. The three auxiliary pixel electrodes 150 and three pixel electrodes 119 arranged in order in the row direction correspond to the three self-light emitting regions 100aR, 100aG and 100aB arranged in order in the row direction.

  Further, as shown in FIG. 3 and FIG. 4, in the display panel 10, a plurality of first auxiliary electrode layers 135 are continuously arranged in the column direction between unit pixels 100e on the substrate 100x. The first auxiliary electrode layer 135 is made of a light reflecting material different from the pixel electrode 119. In addition, on each first auxiliary electrode layer 135, the second auxiliary electrode layer 200 is continuously disposed in the column direction between unit pixels 100e on the substrate 100x. The second auxiliary electrode layer 200 is made of the same light reflecting material as the pixel electrode 119. The width of the first auxiliary electrode layer 135 in the row direction is wider than the width of the second auxiliary electrode layer 200 in the row direction.

Between the adjacent pixel electrodes 119, banks extending in a line shape of insulating layer type are provided. Further, also between the adjacent pixel electrode 119 and the first auxiliary electrode layer 135, a bank extending in a line shape of insulating layer type is provided.
The pixel electrode 119 and the pixel electrode 119 adjacent thereto are insulated from each other. The pixel electrode 119 and the second auxiliary electrode layer 200 or the first auxiliary electrode layer 135 adjacent to the pixel electrode 119 are insulated from each other.

  Between one pixel electrode 119 and the pixel electrode 119 adjacent thereto in the row direction (that is, the outer edge 119a3 of the one pixel electrode 119 in the row direction), and the pixel electrode 119 adjacent to the pixel electrode 119 in the row direction. Between the row-direction outer edge 119a4), one pixel electrode 119 and the first auxiliary electrode layer 135 adjacent thereto in the row direction (ie, the row-direction outer edge 119a3 of one pixel electrode 119) Between the first auxiliary electrode layer 135 adjacent to the pixel electrode 119 in the row direction and the outer edge 119 a 4 of the one pixel electrode 119 in the row direction, and the pixel electrode 119 in the row direction Column banks 522 extend in the column direction (Y direction in FIG. 3) above the region on the substrate 100 x located between the adjacent first auxiliary electrode layers 135 and the outer edge 200 a 1 in the row direction). There are multiple Retsunami set. Therefore, the row direction outer edge of the self light emitting area 100a is defined by the row direction outer edge of the column bank 522Y.

  On the other hand, between one pixel electrode 119 and a pixel electrode 119 adjacent thereto in the column direction (that is, an outer edge 119a2 of the one pixel electrode 119 in the column direction) and a pixel electrode adjacent to the pixel electrode 119 in the column direction Above the region on the substrate 100x positioned between the outer edge 119a1 in the column direction 119), a plurality of row banks 122X are arranged in parallel, each row extending in the row direction (X direction in FIG. 3). The region where the row bank 122X is formed becomes the non-self light emitting region 100b because organic electroluminescence does not occur in the light emitting layer 123 above the pixel electrode 119. Therefore, the outer edge in the column direction of the light emitting region 100a is defined by the outer edge in the column direction of the row bank 122X.

  When the space between adjacent row banks 522Y is defined as a space 522z, a red space 522zR corresponding to the self light emitting area 100aR, a green space 522zG corresponding to the self light emitting area 100aG, and a blue space corresponding to the self light emitting area 100aB 522zB, an auxiliary gap 522zA corresponding to a region where the first auxiliary electrode layer 135 is disposed (hereinafter, the gap 522zR, the gap 522zG, the gap 522zB, and the gap 522zA are referred to as “gap 522z” when not distinguished), The display panel 10 has a configuration in which a large number of column banks 522Y and gaps 522z are alternately arranged.

  In the display panel 10, the plurality of self light emitting areas 100a and the non self light emitting areas 100b are alternately arranged in the column direction along the gaps 522zR, the gaps 522zG, and the gaps 522zB. The non-self light emitting region 100 b has a connection recess (contact hole, not shown) connecting the pixel electrode 119 and the source S 1 of the TFT, and is provided on the pixel electrode 119 for electrical connection to the pixel electrode 119. A contact area (contact window, not shown) is provided.

In one sub-pixel 100se, the column bank 522Y provided in the column direction and the row bank 122X provided in the row direction are orthogonal to each other, and the self light emitting region 100a corresponds to the row bank 122X and the row bank 122X in the column direction. It is located between adjacent row banks 122X.
1.4 Configuration of Each Part of Display Panel 10 The configuration of the organic EL element 100 in the display panel 10 will be described with reference to FIGS. 4 and 5. FIG. 4 is a schematic cross-sectional view taken along line A1-A1 in FIG. FIG. 5 is an enlarged view of the periphery of the second auxiliary electrode layer 200 shown in FIG.

In the display panel 10 according to the present embodiment, a substrate (TFT substrate) on which thin film transistors are formed in the lower side in the Z-axis direction is formed, and an organic EL element portion is formed thereon.
1.4.1 Substrate (1) Substrate 100x
The substrate 100x is a support member for the display panel 10, and has a base (not shown) and a thin film transistor (TFT) layer (not shown) formed on the base.

The base material is a support member of the display panel 10 and is flat. As a material of the substrate, a material having electrical insulation, such as a glass material, a resin material, a semiconductor material, a metal material coated with an insulating layer, or the like can be used.
The TFT layer is composed of a plurality of TFTs formed on the upper surface of the substrate and a plurality of wirings including a plurality of TFTs (the source S1 of the TFT is connected to the corresponding pixel electrode 119). The TFT electrically connects the pixel electrode 119 corresponding to itself to an external power supply in response to a drive signal from the external circuit of the display panel 10, and has a multilayer structure of an electrode, a semiconductor layer, an insulating layer, etc. . The wirings electrically connect the TFT, the pixel electrode 119, an external power supply, an external circuit, and the like.

(2) Interlayer insulating layer 118
An interlayer insulating layer 118 is provided on the substrate and on the upper surface of the TFT layer. The interlayer insulating layer 118 located on the upper surface of the substrate 100x is for planarizing the upper surface of the substrate 100x in which unevenness is present by the TFT layer. Further, the interlayer insulating layer 118 fills in between the wiring and the TFT, and electrically insulates between the wiring and the TFT.

In the interlayer insulating layer 118, in order to connect the pixel electrode 119 and the wiring connected to the source S1 of the corresponding pixel, a contact hole (shown in the drawing) is provided corresponding to the pixel electrode 119. Not) has been established.
When the upper limit film thickness of the interlayer insulating layer 118 is 10 μm or more, the film thickness variation at the time of manufacturing becomes larger, and control of the bottom line width becomes difficult. The upper limit of the film thickness of the interlayer insulating layer 118 is preferably 7 μm or less from the viewpoint of productivity decrease due to increase in tact. In addition, it is necessary to make the film thickness of the interlayer insulating layer 118 and the bottom line width approximately the same, and when the film thickness of the interlayer insulating layer 118 becomes thin, the resolution particularly when the lower limit film thickness of the interlayer insulating layer 118 is 1 μm or less It becomes difficult to obtain the desired bottom line width due to In the case of a general exposure apparatus for flat panel display, the lower limit film thickness of the interlayer insulating layer 118 is 2 μm. Therefore, the thickness of the interlayer insulating layer 118 is preferably, for example, 1 μm to 10 μm, and more preferably 2 μm to 7 μm.

1.4.2 Organic EL Element Section (1) Auxiliary Pixel Electrode 150 and Pixel Electrode 119
As shown in FIGS. 4 and 5, on the interlayer insulating layer 118 positioned on the upper surface of the substrate 100x, the auxiliary pixel electrode 150 is provided in units of sub-pixels 100se. Furthermore, the pixel electrode 119 is stacked on the auxiliary pixel electrode 150.

  The auxiliary pixel electrode 150 and the pixel electrode 119 are for supplying carriers to the light emitting layer 123, and for example, when functioning as an anode, holes are supplied to the light emitting layer 123. Further, since the display panel 10 is a top emission type, the pixel electrode 119 has light reflectivity. The shape of the auxiliary pixel electrode 150 and the pixel electrode 119 is a rectangular plate. The auxiliary pixel electrode 150 and the pixel electrode 119 are arranged in the row direction with an interval δX1 between the adjacent first auxiliary electrode layer 135. In addition, the auxiliary pixel electrode 150 and the pixel electrode 119 are disposed in the row direction with an interval δX2 between the adjacent auxiliary pixel electrode 150 and the pixel electrode 119. A connection recess (contact hole; not shown) of the pixel electrode 119 in which a part of the pixel electrode 119 is recessed in the direction of the substrate 100 x is formed on the contact hole (not shown) of the interlayer insulating layer 118 At the bottom of the connection recess, the pixel electrode 119 is connected to the wiring connected to the source S1 of the corresponding pixel.

By forming the auxiliary pixel electrode 150 over the interlayer insulating layer 118, adhesion is enhanced and hydrogen can be prevented from entering the lower layer than the interlayer insulating layer 118.
Note that the auxiliary pixel electrode 150 may not be formed on the interlayer insulating layer 118.
(2) First auxiliary electrode layer 135 and second auxiliary electrode layer 200
As shown in FIGS. 4 and 5, a first auxiliary electrode layer 135 is provided on the interlayer insulating layer 118 located on the upper surface of the substrate 100x. As shown in FIG. 5, the first auxiliary electrode layer 135 is disposed between the adjacent pixel electrodes 119 with a space δX1 in the row direction. Further, as shown in FIG. 5, the first auxiliary electrode layer 135 is disposed between the base portion 140 of the adjacent bank 522 with an interval W3 in the row direction.

Note that the first auxiliary electrode layer 135 may be in contact with the base 140 of the adjacent bank 522 without leaving the space W3.
Here, the thickness of the first auxiliary electrode layer 135 is, for example, 50 nm.
Further, as shown in FIGS. 4 and 5, the second auxiliary electrode layer 200 is stacked on the first auxiliary electrode layer 135. The width W1 of the second auxiliary electrode layer 200 in the row direction is smaller than the width W2 of the first auxiliary electrode layer 135 in the row direction. That is, the surface area of the second auxiliary electrode layer 200 is smaller than the surface area of the first auxiliary electrode layer 135.

(3) Hole injection layer 120
As shown in FIG. 4, the hole injection layer 120 is stacked on the pixel electrode 119. The hole injection layer 120 has a function of transporting holes injected from the pixel electrode 119 to the hole transport layer 121.
The hole injection layer 120 includes a lower layer 120A of metal oxide formed on the pixel electrode 119 and an upper layer 120B of organic material stacked on at least the lower layer 120A sequentially from the substrate 100x side. Lower layers 120A provided in the blue sub-pixel, the green sub-pixel, and the red sub-pixel are referred to as a lower layer 120AB, a lower layer 120AG, and a lower layer 120AR, respectively. In addition, upper layers 120B provided in the blue sub-pixel, the green sub-pixel, and the red sub-pixel are referred to as an upper layer 120BB, an upper layer 120BG, and an upper layer 120BR, respectively.

In the present embodiment, in the gaps 522zR, the gaps 522zG, and the gaps 522zB described later, the upper layer 120B is linearly provided so as to extend in the column direction. However, the upper layer 120B may be formed only on the lower layer 120A formed on the pixel electrode 119, and may be intermittently provided in the column direction in the gap 522z.
(4) Bank 122
As shown in FIGS. 4 and 5, a bank made of an insulator is formed to cover the edge of the pixel electrode 119, the hole injection layer 120, the first auxiliary electrode layer 135, and the second auxiliary electrode layer 200. . The banks include column banks 522Y extending in the column direction and arranged in parallel in the row direction, and row banks 122X extending in the row direction and arranged in parallel in the column direction. As shown in FIG. 3, the column banks 522Y are provided along the row direction orthogonal to the row banks 122X, and the column banks 522Y and the row banks 122X form a lattice (hereinafter row banks). 122X, column bank 522 Y is referred to as “bank 122” when not distinguished from each other).

  The shape of the row bank 122X is linear extending in the row direction, and the cross section cut in parallel to the column direction is a forward tapered trapezoidal shape whose upper side is tapered. The row banks 122X are provided along the row direction orthogonal to the column direction so as to penetrate each column bank 522Y, and each has an upper surface at a position lower than the upper surface 522Yb of the column bank 522Y. Therefore, an opening corresponding to the self light emitting area 100a is formed by the row bank 122X and the column bank 522Y.

  The row bank 122 </ b> X is for controlling the flow in the column direction of the ink containing the organic compound to be the material of the light emitting layer 123. Therefore, the row bank 122X needs to have a lyophilic property with respect to the ink equal to or more than a predetermined value. With such a configuration, fluctuation of the ink application amount between the sub-pixels is suppressed. The pixel electrode 119 is not exposed by the row bank 122X, does not emit light in the region where the row bank 122X exists, and does not contribute to the luminance.

The row bank 122 </ b> X is present above the outer edges 119 a 1 and a 2 in the column direction of the pixel electrode 119.
The row bank 122X prevents electrical leakage with the common electrode layer 125 and defines the outer edge of the light emitting region 100a of each sub pixel 100se in the column direction.
The shape of the column bank 522Y is linear extending in the column direction, and the cross section cut parallel to the row direction is a forward tapered trapezoidal shape whose upper side is tapered. The column bank 522Y defines the row direction outer edge of the light emitting layer 123 which is formed by blocking the flow in the row direction of the ink containing the organic compound to be the material of the light emitting layer 123.

  The column bank 522Y has its base in the row direction defined by the upper side of the outer edges 119a3 and a4 in the row direction of the pixel electrodes 119 and the outer edges 200a1 and a2 in the row direction of the first auxiliary electrode layer 135. The column bank 522Y prevents electrical leakage with the common electrode layer 125, and defines the outer edge of the light emitting region 100a of each subpixel 100se in the row direction. The column bank 522Y needs to have the liquid repellency to ink equal to or more than a predetermined value.

(5) Hole transport layer 121
As shown in FIG. 4, the hole transport layer 121 is stacked on the hole injection layer 120 in the gaps 522zR, 522zG, 522zB. In addition, the hole transport layer 121 is stacked also on the hole injection layer 120 in the row bank 122X (not shown). The hole transport layer 121 is in contact with the upper layer 120 B of the hole injection layer 120. The hole transport layer 121 has a function of transporting holes injected from the hole injection layer 120 to the light emitting layer 123. The hole transport layers 121 provided in the gaps 522zR, 522zG, and 522zB are respectively referred to as a hole transport layer 121R, a hole transport layer 121G, and a hole transport layer 121B.

In the present embodiment, the hole transport layer 121 is linearly provided so as to extend in the column direction in the gap 522z described later, as in the upper layer 120B. However, the hole transport layer 121 may be provided intermittently in the column direction in the gap 522z.
(6) Light emitting layer 123
As shown in FIG. 4, the light emitting layer 123 is stacked on the hole transport layer 121. The light emitting layer 123 is a layer made of an organic compound, and has a function of emitting light by the recombination of holes and electrons inside. In the gaps 522zR, the gaps 522zG, and the gaps 522zB defined by the column banks 522Y, the light emitting layers 123 are linearly provided so as to extend in the column direction. Red gap 522zR corresponding to self-emission area 100aR in red sub-pixel 100seR, green space 522zG corresponding to self-emission area 100aG in green sub-pixel 100seG, blue space 522zB corresponding to self-emission area 100aB in blue sub-pixel 100seB The light emitting layers 123R, 123G, and 123B which respectively emit light of each color are formed on the

  In the light emitting layer 123, only a portion to which carriers are supplied from the pixel electrode 119 emits light, so that the electroluminescent phenomenon of the organic compound does not occur in the range where the row bank 122X which is an insulator is present between the layers. Therefore, in the light emitting layer 123, only the portion without the row bank 122X emits light, and this portion becomes the self light emitting region 100a, and the outer edge in the column direction of the self light emitting region 100a is defined by the column direction outer edge of the row bank 122X .

A portion of the light emitting layer 123 above the side surface and the top surface of the row bank 122X does not emit light, and this portion becomes a non-self light emitting region. The light emitting layer 123 is located on the top surface of the hole transport layer 121 in the self light emitting region, and is located on the top surface and the top surface of the hole transport layer 121 on the side surface of the row bank 122X in the non self light emitting region 100b (not shown).
The light emitting layer 123 is continuously extended not only to the self light emitting area 100 a but also to the adjacent non self light emitting area. Thus, when the light emitting layer 123 is formed, the ink applied to the self light emitting area 100a can flow in the column direction through the ink applied to the non-self light emitting area, and the film thickness is equalized between the pixels in the column direction. Can be However, in the non-self light emitting area, the flow of ink is moderately suppressed by the row bank 122X. Therefore, large film thickness unevenness in the column direction is less likely to occur, and luminance unevenness in each pixel is improved.

(7) Electron transport layer 124
As shown in FIGS. 3, 4 and 5, the electron transport layer 124 is formed in a stacked manner so as to cover the gaps 522 z defined by the column banks 522 Y and the column banks 522 Y. The electron transport layer 124 is formed continuously to the entire display panel 10.
The electron transport layer 124 is formed on the light emitting layer 123 as shown in FIG. 4 and FIG. The electron transport layer 124 has a function of transporting electrons from the common electrode layer 125 to the light emitting layer 123 and restricting electron injection to the light emitting layer 123.

  As shown in FIGS. 4 and 5, the electron transport layer 124 includes a first auxiliary electrode layer 135 (except for the portion on the first auxiliary electrode layer 135 where the second auxiliary electrode layer 200 is formed) and the second auxiliary electrode layer 135. It is also formed on the electrode layer 200. The electron transport layer 124 is missing (cut off) at the end of the first auxiliary electrode layer 135 and the end of the second auxiliary electrode layer 200. In the missing parts 136 and 139, the first auxiliary electrode layer 135 and the common electrode layer 125 are in direct contact with each other. In addition, in the missing portions 137 and 138, the first auxiliary electrode layer 135 and the common electrode layer 125 are in direct contact, and the second auxiliary electrode layer 200 and the common electrode layer 125 are in direct contact.

(8) Common electrode layer 125
As shown in FIGS. 4 and 5, the common electrode layer 125 is formed on the electron transport layer 124. The common electrode layer 125 is formed over the entire surface of the display panel 10 and serves as a common electrode for each light emitting layer 123.
The common electrode layer 125 is also formed in a region above the pixel electrode 119 on the electron transport layer 124, as shown in FIG. The common electrode layer 125 forms a current path by pairing the light emitting layer 123 with the pixel electrode 119 to supply a carrier to the light emitting layer 123. For example, when it functions as a cathode, the light emitting layer 123 is used. Supply the electron.

  The common electrode layer 125 is, as shown in FIGS. 4 and 5, the first auxiliary electrode layer 135 (except for the portion on the first auxiliary electrode layer 135 where the second auxiliary electrode layer 200 is formed) and the second auxiliary electrode layer 135. A region above the electrode layer 200 is also formed. The common electrode layer 125 is formed to be in direct contact with the first auxiliary electrode layer 135 and the second auxiliary electrode layer 200 in the missing parts 136, 137, 138, 139 of the electron transport layer 124.

(9) Sealing layer 126
A sealing layer 126 is stacked to cover the common electrode layer 125. The sealing layer 126 is for suppressing the light emitting layer 123 from being exposed to moisture, air, or the like and deteriorating. The sealing layer 126 is provided over the entire surface of the display panel 10 so as to cover the upper surface of the common electrode layer 125.

(10) Bonding layer 127
A color filter substrate 131 on which a color filter layer 128 is formed on the main surface of the upper substrate 130 below the Z-axis direction is disposed above the sealing layer 126 in the Z-axis direction. There is. The bonding layer 127 has a function to prevent the layers from being exposed to moisture or air, as well as bonding the color filter substrate 131 to the back panel consisting of the layers from the substrate 100 x to the sealing layer 126.

(11) Upper substrate 130
On the bonding layer 127, a color filter substrate 131 in which the color filter layer 128 is formed on the upper substrate 130 is installed and bonded. For the upper substrate 130, since the display panel 10 is a top emission type, for example, a light transmitting material such as a cover glass or a transparent resin film is used. In addition, the upper substrate 130 can improve the rigidity of the display panel 10 and prevent entry of moisture, air, and the like.

(12) Color filter layer 128
A color filter layer 128 is formed on the upper substrate 130 at a position corresponding to each color self-emission area 100 a of the pixel. The color filter layer 128 is a transparent layer provided to transmit visible light of wavelengths corresponding to R, G and B, and has a function of transmitting light emitted from each color pixel and correcting its chromaticity. Have. For example, in this example, the red, green, and blue filter layers 128R and 128G above the self-emission area 100aR in the red gap 522zR, the self-emission area 100aG in the green gap 522zG, and the self-emission area 100aB in the blue gap 522zB. , 128B are respectively formed.

(13) Light shielding layer 129
A light shielding layer 129 is formed on the upper substrate 130 at a position corresponding to the boundary between the light emitting regions 100 a of the respective pixels. The light shielding layer 129 is a black resin layer provided to prevent transmission of visible light of wavelengths corresponding to R, G, and B, and is made of, for example, a resin material containing a black pigment excellent in light absorption and light shielding.

1.4.3 Constituent materials of each part An example is shown about the constituent material of each part shown in FIG.3, FIG4 and FIG.5.
(1) Substrate 100x (TFT substrate)
Examples of the substrate include glass substrates, quartz substrates, silicon substrates, metal substrates such as molybdenum sulfide, copper, zinc, aluminum, stainless steel, magnesium, iron, nickel, gold and silver, semiconductor substrates such as gallium arsenide, plastics A substrate or the like can be employed. Further, as the plastic material having flexibility, any resin of thermoplastic resin and thermosetting resin may be used. As the material, a material having electrical insulation, for example, a resin material can be used. Known materials can be used for the gate electrode, the gate insulating layer, the channel layer, the channel protective layer, the source electrode, the drain electrode, and the like that constitute the TFT. As the gate electrode, for example, a laminate of copper (Cu) and molybdenum (Mo) is employed. As the gate insulating layer, any of known organic materials and inorganic materials can be used as long as it is a material having electrical insulation such as silicon oxide (SiO ₂ ), silicon nitride (SiN x), or the like. As the channel layer, an oxide semiconductor containing at least one selected from indium (In), gallium (Ga), and zinc (Zn) can be employed. As the channel protective layer, for example, silicon oxynitride (SiON), silicon nitride (SiNx), or aluminum oxide (AlOx) can be used. As the source electrode and the drain electrode, for example, a stacked body of copper manganese (CuMn), copper (Cu), and molybdenum (Mo) can be employed.

For example, silicon oxide (SiO ₂ ), silicon nitride (SiN), silicon oxynitride (SiON), silicon oxide (SiO) or silicon oxynitride (SiON) can be used as the insulating layer on the top of the TFT. As a connection electrode layer of a TFT, for example, a laminate of molybdenum (Mo), copper (Cu), and copper manganese (CuMn) can be employed. In addition, as a material used for the structure of a connection electrode layer, it is not limited to this, It is possible to select suitably from the material which has electroconductivity.

As a material of the interlayer insulating layer 118 located on the upper surface of the substrate 100x, for example, an organic compound such as polyimide resin, acrylic resin, siloxane resin, or novolac phenol resin can be used.
(2) Pixel electrode 119, auxiliary pixel electrode 150, second auxiliary electrode layer 200, and first auxiliary electrode layer 135
The pixel electrode 119 is made of a metal material. In the case of the display panel 10 according to the top emission type in this embodiment, the thickness is optimally set and the optical resonator structure is adopted to adjust the chromaticity of the emitted light to increase the luminance. The surface portion of the pixel electrode 119 needs to have high reflectivity. In the display panel 10 according to the present embodiment, the pixel electrode 119 may have a structure in which a plurality of films selected from a metal layer, an alloy layer, and a transparent conductive film are stacked. The metal layer can be made of, for example, a metal material containing silver (Ag) or aluminum (Al). As the alloy layer, use, for example, APC (silver, palladium, copper alloy), ARA (silver, rubidium, gold alloy), MoCr (molybdenum and chromium alloy), NiCr (nickel and chromium alloy), etc. Can. As a constituent material of the transparent conductive layer, for example, indium tin oxide (ITO) or indium zinc oxide (IZO) can be used.

The second auxiliary electrode layer 200 is formed of the same material as the pixel electrode 119.
The first auxiliary electrode layer 135 is formed of, for example, a metal material such as tungsten (W), molybdenum (Mo), nickel (Ni), copper (Cu), lanthanum (La), indium (In) or the like.
The auxiliary pixel electrode 150 is formed of the same material as the first auxiliary electrode layer 135.

(3) Hole injection layer 120
The lower layer 120A of the hole injection layer 120 is, for example, an oxide such as silver (Ag), molybdenum (Mo), chromium (Cr), vanadium (V), tungsten (W), nickel (Ni), iridium (Ir) or the like. It is a layer consisting of When the lower layer 120A is made of a transition metal oxide, it can take a plurality of levels because it takes a plurality of oxidation numbers, as a result, hole injection becomes easy and drive voltage is reduced. Can. In the present embodiment, the lower layer 120A is configured to include an oxide of tungsten (W). At this time, since the tungsten (W) oxide has a larger ratio (W ⁵⁺ / W ^{6 +} ) of hexavalent tungsten atoms of pentavalent tungsten atoms, the driving voltage of the organic EL element becomes lower. It is preferable to include more atoms than a predetermined value.

As described above, the upper layer 120B of the hole injection layer 120 can use, for example, a coating film made of an organic polymer solution of a conductive polymer material such as PEDOT (a mixture of polythiophene and polystyrene sulfonic acid).
(4) Bank 122
The bank 122 is formed using an organic material such as a resin and has insulating properties. Examples of the organic material used to form the bank 122 include acrylic resins, polyimide resins, and novolac phenolic resins. The bank 122 preferably has organic solvent resistance. More preferably, it is desirable to use an acrylic resin. This is because the refractive index is low and suitable as a reflector.

Alternatively, in the case where the bank 122 uses an inorganic material, it is preferable to use, for example, silicon oxide (SiO) from the viewpoint of the refractive index. Alternatively, for example, an inorganic material such as silicon nitride (SiN) or silicon oxynitride (SiON) is used.
Furthermore, since the banks 122 may be subjected to etching processing, baking processing and the like during the manufacturing process, they should be formed of a highly resistant material that does not excessively deform or deteriorate the processing. Is preferred.

In addition, in order to make the surface water repellant, the surface can also be fluorinated. Alternatively, a material containing fluorine may be used to form the bank 122. Also, in order to lower the water repellency of the surface of the bank 122, the bank 122 may be irradiated with ultraviolet light, or may be baked at a low temperature.
(5) Hole transport layer 121
The hole transport layer 121 is made of, for example, polyfluorene or a derivative thereof, a polymer compound such as polyarylamine which is an amine-based organic polymer or a derivative thereof, or TFB (poly (9,9-di-n-octylfluorene- For example, alt- (1, 4-phenylene-((4-sec-butylphenyl) imino) -1, 4-phenylene)) can be used.

(6) Light emitting layer 123
As described above, the light emitting layer 123 has a function of generating an excited state and emitting light by the holes and the electrons being injected and recombined. As a material used for forming the light emitting layer 123, it is necessary to use a light emitting organic material which can be formed into a film by a wet printing method.
Specifically, for example, an oxinoid compound, a perylene compound, a coumarin compound, an azquamarin compound, an oxazole compound, an oxadiazole compound, a perinone compound, a pyrrolopyrrole described in a patent publication (Japanese Patent Application Laid-Open No. 5-163488). Compounds, naphthalene compounds, anthracene compounds, fluorene compounds, fluorene 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, fluorene In compounds, pyrilium compounds, thiapyrilium compounds, selenapyrilium compounds, telluropyrilium compounds, aromatic aldadiene compounds, oligophenylene compounds, thioxanthene compounds, anthracene compounds, cyanine compounds, acridine compounds, metal complexes of 8-hydroxyquinoline compounds, 2- It is preferable to be formed of a fluorescent substance such as a metal complex of a bipyridine compound, a complex of a Schiff salt and a Group III metal, an oxine metal complex, a rare earth complex and the like.

(7) Electron transport layer 124
The electron transport layer 124 is made of an organic material having high electron transportability. Examples of the organic material used for the electron transport layer 124 include π electron low molecular weight organic materials such as oxadiazole derivative (OXD), triazole derivative (TAZ), and phenanthroline derivative (BCP, Bphen). In addition, the electron transporting layer 124 may include a layer formed by doping an organic material with high electron transporting property with a doped metal selected from an alkali metal or an alkaline earth metal. In addition, the electron transport layer 124 may include a layer formed of sodium fluoride. Specifically, the alkali metal is Li (lithium), Na (sodium), K (potassium), Rb (rubidium), Cs (cesium), Fr (francium). Specifically, the alkaline earth metal is Ca (calcium), Sr (strontium), Ba (barium), or Ra (radium).

(8) Common electrode layer 125
The common electrode layer 125 is made of a light-transmitting conductive material. For example, indium tin oxide (ITO) or indium zinc oxide (IZO) is used. Alternatively, an electrode in which silver (Ag) or aluminum (Al) or the like is thinned may be used.
(9) Sealing layer 126
The sealing layer 126 has a function of suppressing exposure of an organic layer such as the light emitting layer 123 to moisture or air, and may be, for example, silicon nitride (SiN), silicon oxynitride (SiON), or the like. It forms using the translucent material. In addition, a sealing resin layer made of a resin material such as an acrylic resin or a silicon resin may be provided on a layer formed using a material such as silicon nitride (SiN) or silicon oxynitride (SiON).

In the case of the display panel 10 according to the present embodiment, which is a top emission type, the sealing layer 126 needs to be formed of a light transmitting material.
(10) Bonding layer 127
The material of the bonding layer 127 is made of, for example, a resin adhesive. The bonding layer 127 can employ a light-transmitting material resin material such as an acrylic resin, a silicon resin, or an epoxy resin.

(11) Upper substrate 130
As the upper substrate 130, for example, a translucent material can be employed for a glass substrate, a quartz substrate, a plastic substrate, and the like.
(12) Color filter layer 128
As the color filter layer 128, a known resin material (for example, a commercially available product, a color resist manufactured by JSR Corporation) or the like can be adopted.

(13) Light shielding layer 129
The light shielding layer 129 is made of a resin material which is mainly made of an ultraviolet curable resin (for example, ultraviolet curable acrylic resin) material and to which a black pigment is added. As the black pigment, for example, a light shielding material such as a carbon black pigment, a titanium black pigment, a metal oxide pigment, and an organic pigment can be adopted.

1.5 Method of Manufacturing Display Panel 10 A method of manufacturing the display panel 10 will be described with reference to FIGS.
(1) Preparation of Substrate 100x A substrate 100x on which a plurality of TFTs and wirings are formed is prepared. The substrate 100x can be manufactured by a known TFT manufacturing method (FIG. 6A).

(2) Formation of interlayer insulating layer 118 An interlayer insulating layer is formed by applying the above-mentioned constituent material (photosensitive resin material) of the interlayer insulating layer 118 as a photoresist so as to cover the substrate 100x and planarizing the surface. 118 is formed (FIG. 6 (b)).
After the interlayer insulating layer 118 is formed, a photomask having a predetermined opening is overlaid, and ultraviolet light is irradiated from above to expose the interlayer insulating layer 118, thereby transferring the pattern of the photomask (FIG. 6 (c )).

Thereafter, development is performed to form an interlayer insulating layer 118 in which the contact holes 118a are patterned (FIG. 6 (d)). The wiring on the substrate 100x is exposed at the bottom of the contact hole 118a.
In this embodiment mode, the interlayer insulating layer 118 is formed using a positive type photoresist, but the interlayer insulating layer 118 may be formed using a negative type photoresist.

(3) Formation of the auxiliary pixel electrode 150 and the first auxiliary electrode layer 135 After the interlayer insulating layer 118 in which the contact hole 118a is opened is formed, the auxiliary pixel electrode 150 and the first auxiliary electrode layer 135 are formed (FIG. a)).
The auxiliary pixel electrode 150 and the first auxiliary electrode layer 135 are formed by forming a metal film using a sputtering method or the like, and then patterning using a photolithographic method and an etching method. At this time, a connection recess of the auxiliary pixel electrode 150 is formed by forming a metal film along the inner wall of the contact hole 118a.

The auxiliary pixel electrode 150 is in direct contact with the wiring on the substrate 100x exposed at the bottom of the contact hole 118a, and is in a state of being electrically connected to the electrode of the TFT.
(4) Formation of Pixel Electrode 119 and Second Auxiliary Electrode Layer 200 After the auxiliary pixel electrode 150 and the first auxiliary electrode layer 135 are formed, the pixel electrode is formed on the auxiliary pixel electrode 150 and the first auxiliary electrode layer 135, respectively. 119 and the second auxiliary electrode layer 200 are formed (FIG. 7A).

The pixel electrode 119 and the second auxiliary electrode layer 200 are formed by forming a metal film using a sputtering method or the like, and then patterning using a photolithographic method and an etching method.
(5) Formation of lower layer 120A of hole injection layer 120 After forming the pixel electrode 119 and the second auxiliary electrode layer 200, the lower layer 120A of the hole injection layer 120 is formed on the pixel electrode 119 (FIG. 7). (B).

The lower layer 120A is formed by forming a film made of metal (for example, tungsten) by vapor deposition such as sputtering or vacuum evaporation, and then oxidizing the film by baking, and using photolithography and etching to form each pixel unit. It is formed by patterning.
(6) Formation of Bank 122 After the lower layer 120A of the hole injection layer 120 is formed, the bank 122 is formed so as to cover the lower layer 120A (FIG. 7C).

In the formation of the banks 122, the row banks 122X are formed first, and then the column banks 522Y are formed so as to form the gaps 522Z.
To form the bank 122, first, a film made of the constituent material (for example, photosensitive resin material) of the bank 122 is laminated and formed on the lower layer 120A using a spin coating method or the like. Then, the resin film is patterned to form a row bank 122X and a column bank 522Y in order. The patterning of the row bank 122X and the column bank 522Y is performed by performing exposure using a photomask above the resin film and performing a development step and a baking step (about 230 ° C., about 60 minutes).

  Specifically, in the step of forming the row bank 122X, first, a photosensitive resin film made of an organic photosensitive resin material, for example, an acrylic resin, a polyimide resin, a novolac phenol resin, etc., is formed and then dried. After the solvent is volatilized to some extent, a photo mask provided with a predetermined opening is overlaid, and ultraviolet light is irradiated from above to expose a photoresist made of a photosensitive resin or the like, and the photo mask has the photo mask. Transfer the pattern. Next, the photosensitive resin is developed to form an insulating layer in which the row bank 122X is patterned. Generally, a photoresist called positive type is used. In the positive type, exposed portions are removed by development. The portions of the mask pattern that are not exposed remain without being developed.

  In the step of forming the column bank 522Y, first, a film made of a constituent material (for example, a photosensitive resin material) of the column bank 522Y is laminated and formed by spin coating or the like. Then, the resin film is patterned to open a gap 522z to form a column bank 522Y. The formation of the gap 522z is performed by arranging a mask above the resin film, exposing it, and then developing it. The column banks 522Y extend in the column direction, and are arranged side by side in the row direction with a gap 522z.

(7) Formation of Organic Functional Layer The upper layer 120B of the hole injection layer 120 is formed on the lower layer 120A of the hole injection layer 120 formed in the gap 522z defined by the column bank 522Y including the upper side of the row bank 122X. The hole transport layer 121 and the light emitting layer 123 are sequentially laminated (FIG. 7 (d), FIG. 8 (a)).

  The upper layer 120B uses an inkjet method to apply an ink containing a conductive polymer material such as PEDOT (a mixture of polythiophene and polystyrene sulfonic acid) into the gap 522z defined by the row bank 522Y, and then evaporates the solvent. Let Or it is made by baking. Thereafter, patterning may be performed on each pixel unit using a photolithography method and an etching method.

  The hole transport layer 121 applies the ink containing the constituent material in the gap 522z defined by the row bank 522Y using a wet process by an ink jet method or a gravure printing method, and then evaporates and removes the solvent. Or it is made by baking. The method of applying the ink of the hole transport layer 121 in the gap 522z is the same as the method of the upper layer 120B described above. Alternatively, it is formed by depositing a film made of metal (eg, tungsten) using a sputtering method and oxidizing it by firing. Thereafter, patterning may be performed on each pixel unit using a photolithography method and an etching method.

  The formation of the light emitting layer 123 is performed by applying an ink containing the constituent material in the gap 522z defined by the row bank 522Y using an inkjet method, and then firing. Specifically, in this step, ink 123RI, 123GI, and 123BI containing the material of the organic light emitting layer of any one of R, G, and B are filled and filled in the gaps 522z serving as sub-pixel formation regions by the inkjet method. The ink is dried under reduced pressure and baked to form the light emitting layers 123R, 123G, and 123B. At this time, in the application of the ink for the light emitting layer 123, first, a solution for forming the light emitting layer 123 is applied using a droplet discharge device. When the application of the ink for forming any of the red light emitting layer, the green light emitting layer, and the blue light emitting layer on the substrate 100x is finished, the ink of another color is then applied to the substrate, and then the substrate is The step of applying the third color ink is repeated, and the three color inks are applied sequentially. Thus, the red light emitting layer, the green light emitting layer, and the blue light emitting layer are repeatedly formed side by side in the lateral direction of the drawing sheet on the substrate 100x. The details of the method of applying the ink of the light emitting layer 123 in the gap 522z are the same as the method in the upper layer 120B described above.

The method of forming the upper layer 120B of the hole injection layer 120, the hole transport layer 121, and the light emitting layer 123 is not limited to the above method, and methods other than the inkjet method and the gravure printing method, for example, dispenser method, nozzle coating method, spin coating The ink may be dropped and applied by a known method such as printing method, intaglio printing, letterpress printing and the like.
(8) Formation of Electron Transport Layer 124 After the light emitting layer 123 is formed, the electron transport layer 124 is formed on the entire surface of the display panel 10 by vacuum evaporation or the like (FIG. 8B). The electron transport layer 124 is also formed on the second auxiliary electrode layer 200 and the first auxiliary electrode layer 135 (except for the portion on the first auxiliary electrode layer 135 where the second auxiliary electrode layer 200 is formed). . At that time, a drop (step break) is intentionally generated at the end of the second auxiliary electrode layer 200 and the end of the first auxiliary electrode layer 135, and the missing portions 136, 137, 138, 139 (FIG. 5) The film formation is performed so that the end of the second auxiliary electrode layer 200 and the end of the first auxiliary electrode layer 135 are exposed.

(9) Formation of Common Electrode Layer 125 After forming the electron transport layer 124, the common electrode layer 125 is formed by a CVD (Chemical Vapor Deposition) method, sputtering method or the like so as to cover the electron transport layer 124 (see FIG. 8 (c). The common electrode layer 125 is formed of the second auxiliary electrode layer 200 and the first auxiliary electrode layer 135 on the electron transport layer 124 (except for the portion on the first auxiliary electrode layer 135 where the second auxiliary electrode layer 200 is formed). It is also formed in the upper region. At that time, the common electrode layer 125 wraps around the missing parts 136, 137, 138, 139 (FIG. 5) of the electron transporting layer 124, and the end of the second auxiliary electrode layer 200 exposed in the missing part of the electron transporting layer 124. The film is formed to be in direct contact with the portion and the end of the first auxiliary electrode layer 135.

Here, the method of forming the common electrode layer 125 will be further described.
First, the schematic configuration of the sputtering apparatus 600 will be described with reference to FIG. The sputtering apparatus 600 includes a substrate delivery chamber 610, a film forming chamber 620, and a load lock chamber 630. In the film forming chamber 620, sputtering is performed by a magnetron sputtering method. A sputtering gas is introduced into the film forming chamber 620. An inert gas such as Ar (argon) is used as the sputtering gas. In the present embodiment, Ar is used.

  The carrier 621 in the sputtering apparatus 600 is provided with a substrate 622 to be deposited. The substrate 622 is mounted on the carrier 621 by the substrate push-up mechanism 611 in the substrate transfer chamber 610. The carrier 621 mounted with the substrate 622 linearly moves on the transport path 601 at a constant speed from the substrate delivery chamber 610 to the load lock chamber 630 via the deposition chamber 620. In the present embodiment, the moving speed of the carrier 621 is 30 mm / s. Note that the substrate 622 is not heated, and sputtering is performed at normal temperature.

In the film forming chamber 620, a rod-shaped target 623 extending in a direction orthogonal to the transfer path 601 is installed. In the present embodiment, the target 623 is ITO. The target 623 does not have to be rod-like, and may be, for example, powder.
The power supply 624 applies a voltage to the target 623. Although the power supply 624 in FIG. 11 is an AC power supply, it may be a DC power supply or a hybrid power supply of DC / AC.

  The inside of the sputtering apparatus 600 is exhausted by the exhaust system 631, and the sputtering gas is introduced into the film forming chamber 620 by the gas supply system 632. When a voltage is applied to the target 623 by the power supply 624, a plasma of a sputtering gas is generated to sputter the surface of the target 623. Then, a film is formed by depositing atoms of the sputtered target 623 on the substrate 622.

The gas pressure of Ar as a sputtering gas is, for example, 0.6 Pa, and the flow rate is 100 sccm.
(10) Formation of Sealing Layer 126 After forming the common electrode layer 125, the sealing layer 126 is formed to cover the common electrode layer 125 (FIG. 8D). The sealing layer 126 can be formed by a CVD method, a sputtering method, or the like.

(11) Formation of Color Filter Substrate 131 Next, a manufacturing process of the color filter substrate 131 will be illustrated.
A transparent upper substrate 130 is prepared, and a material of a light shielding layer 129 formed by adding a black pigment to an ultraviolet curable resin (for example, an ultraviolet curable acrylic resin) material as a main component is added to one surface of the transparent upper substrate 130 Apply (FIG. 9 (a)).

A pattern mask PM provided with a predetermined opening is superimposed on the upper surface of the applied light shielding layer 129, and ultraviolet irradiation is performed from above (FIG. 9 (b)).
Thereafter, the pattern mask PM and the uncured light shielding layer 129 are removed, developed, and cured to complete the light shielding layer 129 having a rectangular cross-sectional shape (FIG. 9C).
Next, on the surface of the upper substrate 130 on which the light shielding layer 129 is formed, a material 128G of a color filter layer 128 (for example, G) mainly composed of an ultraviolet curable resin component is applied (FIG. 9 (d)) The mask PM is placed, and ultraviolet irradiation is performed (FIG. 9 (e)).

Thereafter, curing is performed, and the pattern mask PM and the uncured paste 128R are removed and developed to form a color filter layer 128 (G) (FIG. 9 (f)).
The color filter layers 128 (R) and 128 (B) are formed by repeating the steps of FIGS. 9 (d), (e) and (f) in the same manner for the color filter material of each color (FIG. 9 (g)). ). In addition, you may utilize the color filter product marketed instead of using the paste 128R.

Thus, the color filter substrate 131 is formed.
(12) Bonding of color filter substrate 131 and rear panel Next, a rear panel consisting of layers from substrate 100x to sealing layer 126 is mainly made of ultraviolet curable resin such as acrylic resin, silicon resin, epoxy resin, etc. The material of the bonding layer 127 to be used is applied (FIG. 10 (a)).

Subsequently, the applied material is irradiated with ultraviolet light, and the two substrates are bonded together in a state where the relative positional relationship between the back panel and the color filter substrate 131 is matched. At this time, be careful not to let gas enter between the two. Thereafter, when the sealing process is completed by firing both substrates, the display panel 10 is completed (FIG. 10 (b)).
1.6 Summary When a metal such as aluminum, copper or silver is used as the material of the auxiliary electrode layer, an oxide film is formed on the surface (surface layer) of the auxiliary electrode layer, and the auxiliary electrode layer and the common electrode layer The contact resistance of the

  In order to solve this problem, in the display panel 10, a plurality of pixel electrodes 119 are arranged in a matrix on the substrate 100x, and a light emitting layer 123 containing an organic light emitting material is formed on each pixel electrode 119. . The display panel 10 includes a substrate 100x, a plurality of pixel electrodes 119 arranged in a matrix above the substrate 100x, and a column above at least one of the gaps between the adjacent pixel electrodes 119 above the substrate 100x. Or a first auxiliary electrode layer 135 extended in the row direction, and a second auxiliary electrode extended in the same direction as the first auxiliary electrode layer 135 in a partial region on the first auxiliary electrode layer 135 The upper surface excluding the layer 200, the plurality of light emitting layers 123 disposed on the plurality of pixel electrodes 119, the plurality of light emitting layers 123, and the partial area of the first auxiliary electrode layer 135, and the second auxiliary electrode layer 200 And a common electrode layer 125 disposed continuously over the upper surface. Here, the first auxiliary electrode layer 135 mainly contains a first metal, and the second auxiliary electrode layer 200 mainly contains a second metal different from the first metal. The resistance of the surface layer of the second auxiliary electrode layer 200 is higher than the resistance of the surface layer of the first auxiliary electrode layer 135.

  According to this configuration, the common electrode layer 125 contacts the first auxiliary electrode layer 135 (except for the partial region described above), and the first auxiliary electrode layer 135 contacts the second auxiliary electrode layer 200. That is, the common electrode layer 125 contacts the second auxiliary electrode layer 200 via the first auxiliary electrode layer 135. For this reason, even when an oxide film is formed on the surface layer of the second auxiliary electrode layer 200, the electrical connection between the common electrode layer and the second auxiliary electrode layer can be achieved by interposing the first auxiliary electrode layer 135. It is possible to reduce the electrical resistance in connection. As a result, it is possible to improve the light emission efficiency and to suppress the uneven brightness.

Here, when tungsten or molybdenum is used as the material of the first auxiliary electrode layer 135, an oxide film is formed on the surface of the first auxiliary electrode layer 135 because these metals are chemically stable at room temperature. I will not.
The contact resistance between the second auxiliary electrode layer 200 and the common electrode layer 125 is higher than a first predetermined value, and the resistance between the first auxiliary electrode layer 135 and the common electrode layer 125 is a first predetermined value. Lower.

The sheet resistance of the second auxiliary electrode layer 200 is lower than the second predetermined value, and the sheet resistance of the first auxiliary electrode layer 135 is higher than the sheet resistance of the second auxiliary electrode layer 200, and the sheet of the common electrode layer 125 is The resistance is higher than a second predetermined value.
By bringing the common electrode layer 125 into contact with the first auxiliary electrode layer 135 (excluding the portion on which the second auxiliary electrode layer 200 is formed), the space between the common electrode layer 125 and the second auxiliary electrode layer 200 is obtained. The resistance can be reduced more than the contact resistance of.

Further, since the sheet resistance of the second auxiliary electrode layer 200 is smaller than the sheet resistance of the first auxiliary electrode layer 135, the first auxiliary electrode layer 135 and the second auxiliary electrode layer 200 as a whole are made of a first metal (for example, Compared to the case where tungsten is used, the overall sheet resistance of the first auxiliary electrode layer 135 and the second auxiliary electrode layer 200 can be reduced.
In addition, as shown in FIG. 5, in the electron transport layer 124, a drop (cut) occurs at the end of the second auxiliary electrode layer 200 and the end of the first auxiliary electrode layer 135, and the drop portion 136 At 137, 138, and 139, since the common electrode layer 125 and the first auxiliary electrode layer 135 are in direct contact, and the common electrode layer 125 and the second auxiliary electrode layer 200 are in direct contact, resistance can be reduced. Become.

1.7 Modifications Although the display panel 10 according to the first embodiment has been described, the present disclosure is not limited at all to the above embodiments except for the essential characteristic components. For example, an embodiment obtained by applying various modifications to those skilled in the art to the embodiment, and an embodiment realized by arbitrarily combining components and functions in each embodiment without departing from the spirit of the present invention. Are also included in the present disclosure. Below, the modification of the display panel 10 is demonstrated as an example of such a form.

(1) In the missing portions 136, 137, 138, and 139 shown in FIG. 5, the thin film of the electron transport layer 124 may be formed without the occurrence of missing (step disconnection).
In the electron transport layer 124, at least a part of the missing parts 136, 137, 138, and 139 shown in FIG. 5 can not be lost, but the thinned part is partially thinned to a film thickness of 1 nm or less (Not shown) may be formed. With such a configuration, a portion of the electron transport layer 124 is not lost, but the common electrode layer 125 has a lower electrical resistance in the thinned portion of the electron transporting layer 124 than in the portion other than the thinned portion. A structure electrically connected to the second auxiliary electrode layer 200 or the first auxiliary electrode layer 135 can be realized. As a result, the electrical resistance in the electrical connection between the common electrode layer 125 and the second auxiliary electrode layer 200 or the common electrode layer 125 and the first auxiliary electrode layer 135 is reduced, and the light emission efficiency is improved and the luminance unevenness is suppressed. be able to.

(2) In the display panel 10, the light emitting layer 123 is configured to extend continuously in the column direction on the row bank. However, in the above configuration, the light emitting layer 123 may be configured to be interrupted for each pixel on the row bank.
(3) In the display panel 10, the color of the light emitted from the light emitting layer 123 of the sub-pixel 100se arranged in the gap 522z between the column banks 522Y adjacent in the row direction is different from each other, and the row banks 122X adjacent in the column direction The color of the light emitted from the light emitting layer 123 of the sub pixel 100se disposed in the gap is the same. However, in the above configuration, the light emitted from the light emitting layers 123 of the subpixels 100se adjacent in the row direction has the same color, and the light emitted from the light emitting layers 123 of the subpixels 100se adjacent in the column direction has different colors. It is also good. Further, the light emitted from the light emitting layers 123 of the adjacent sub-pixels 100se in both of the matrix directions may be different from each other in color.

(4) In the display panel 10 according to the embodiment, the sub pixel 100se includes three types of red pixel, green pixel, and blue pixel, but the present invention is not limited to this. For example, the light emitting layer may be of one type, or the light emitting layer may be of four types of emitting light of red, green, blue and yellow.
(5) In the above embodiment, the unit pixels 100e are arranged in a matrix, but the present invention is not limited to this. For example, when the spacing between the pixel regions is one pitch, the effect is obtained even for a configuration in which the pixel regions are shifted by half a pitch in the column direction between adjacent gaps. In a display panel in which high definition is in progress, some misalignment in the column direction is difficult to visually distinguish, and even if film thickness unevenness is lined up on a straight line (or a zigzag) having a certain width, it becomes a belt shape on visual observation. Therefore, also in such a case, it is possible to improve the display quality of the display panel by suppressing the uneven brightness from being arranged in a zigzag manner.

  (6) In the above embodiment, the hole injection layer 120, the hole transport layer 121, the light emitting layer 123, and the electron transport layer 124 exist between the pixel electrode 119 and the common electrode layer 125, but the present invention Is not limited to this. For example, instead of using the hole injection layer 120, the hole transport layer 121, and the electron transport layer 124, only the light emitting layer 123 may be present between the pixel electrode 119 and the common electrode layer 125. In addition, for example, a configuration including a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, or the like, or a configuration including a plurality or all of them simultaneously may be used. Further, these layers do not have to be all made of an organic compound, and may be made of an inorganic material or the like.

  (7) In the above embodiment, the light emitting layer 123 is formed using a wet film forming process such as a printing method, a spin coating method, or an inkjet method. However, the present invention is not limited to this. For example, a dry film formation process such as vacuum evaporation, electron beam evaporation, sputtering, reactive sputtering, ion plating, or vapor deposition can also be used. Furthermore, well-known materials can be suitably adopted as the material of each component.

  (8) In the above embodiment, the pixel electrode 119 which is the anode is disposed below the EL element portion, and the pixel electrode 119 is connected to the wiring connected to the source electrode of the TFT. It is also possible to adopt a configuration in which the common electrode layer is disposed at the lower part and the anode is disposed at the upper part. In this case, the cathode disposed below is connected to the drain of the TFT.

(9) In the above embodiment, the configuration in which two transistors Tr1 and Tr2 are provided for one subpixel 100se is adopted, but the present invention is not limited to this. For example, one sub-pixel may have one transistor or three or more transistors.
(10) In the above embodiment, although the top emission type EL display panel is taken as an example, the present invention is not limited to this. For example, the present invention can also be applied to a bottom emission display panel or the like. In such a case, appropriate changes can be made to each configuration.

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Each of the embodiments described above represents a preferable specific example of the present invention. The numerical values, shapes, materials, components, arrangement positions and connection forms of the components, steps, order of steps, and the like shown in the embodiments are merely examples, and are not intended to limit the present invention. Further, among the constituent elements in the embodiment, steps not described in the independent claim indicating the highest concept of the present invention are described as arbitrary constituent elements constituting a more preferable embodiment.

In addition, the order in which the above steps are performed is for illustrating the present invention specifically, and may be an order other than the above. In addition, part of the above steps may be performed simultaneously (in parallel) with other steps.
Further, in order to facilitate understanding of the invention, the scale of components in the drawings referred to in the above embodiments may be different from the actual ones. Further, the present invention is not limited by the description of each of the above embodiments, and can be appropriately modified without departing from the scope of the present invention.

In addition, at least a part of the functions of the embodiments and the modification may be combined.
Furthermore, the present invention also includes various modifications in which modifications within the scope of those skilled in the art can be made to the present embodiment.

  The organic EL display panel and the organic EL display device according to the present invention can be widely used for devices such as a television set, a personal computer, a mobile phone, and various other electronic devices having a display panel.

1 organic EL display device 10 organic EL display panel 100 organic EL element 100 e unit pixel 100 se sub pixel 100 a self light emitting area 100 b non self light emitting area 100 x substrate (TFT substrate)
118 interlayer insulating layer 119 pixel electrode 135 second auxiliary electrode layer 150 auxiliary pixel electrode 200 first auxiliary electrode layer 120 hole injection layer 120 A lower layer 120 B upper layer 121 hole transport layer 122 bank 122 X row bank 522 Y column bank 123 light emitting layer 124 electron Transport layer 125 common electrode layer 126 sealing layer 127 bonding layer 128 color filter layer 130 upper substrate 131 color filter substrate

Claims (7)

An organic EL display panel comprising a plurality of pixel electrodes arranged in a matrix on a substrate, and a light emitting layer containing an organic light emitting material arranged on each pixel electrode.
A substrate,
A plurality of pixel electrodes arranged in a matrix above the substrate;
A first feeding auxiliary electrode layer extended in the column or row direction in the gap of at least one of the gaps of the adjacent pixel electrodes above the substrate;
A second feeding auxiliary electrode layer extended in the same direction as the first feeding auxiliary electrode layer in a partial area on the first feeding auxiliary electrode layer;
A plurality of light emitting layers disposed on the plurality of pixel electrodes;
A common electrode layer is provided continuously covering the upper surface of the plurality of light emitting layers, the upper surface excluding the partial region of the first power supply auxiliary electrode layer, and the upper surface on the second power supply auxiliary electrode layer. ,
The first power feeding auxiliary electrode layer mainly contains a first metal, and the second power feeding auxiliary electrode layer mainly contains a second metal different from the first metal,
An organic EL display panel, wherein the resistance of the surface layer of the second power supply auxiliary electrode layer is higher than the resistance of the surface layer of the first power supply auxiliary electrode layer. The organic EL display panel according to claim 1, wherein a metal oxide film is formed on a surface layer of the second power feeding auxiliary electrode layer. The organic EL display panel according to claim 1, wherein a sheet resistance of the first power feeding auxiliary electrode layer is higher than a sheet resistance of the second power feeding auxiliary electrode layer. The organic EL display panel according to claim 1, wherein the contact resistance between the first feed auxiliary electrode layer and the common electrode layer is lower than the contact resistance between the second feed auxiliary electrode layer and the common electrode layer. . The organic EL display panel according to claim 1, wherein a surface area of the first power supply auxiliary electrode layer is larger than a surface area of the second power supply auxiliary electrode layer. The first metal is tungsten or molybdenum
The organic EL display panel according to claim 1, wherein the second metal is aluminum. A method of manufacturing an organic EL display panel, comprising a plurality of pixel electrodes arranged in a matrix on a substrate, and a light emitting layer containing an organic light emitting material arranged on each pixel electrode.
Forming a plurality of pixel electrodes arranged in a matrix above the substrate by vapor deposition;
Forming a first power supply auxiliary electrode layer, which is extended in the column or row direction, in the gap of at least one of the gaps of the adjacent pixel electrodes above the substrate by vapor deposition;
Forming a second feeding auxiliary electrode layer, which is extended in the same direction as the first feeding auxiliary electrode layer, in a partial region on the first feeding auxiliary electrode layer by a vapor deposition method;
Forming a plurality of light emitting layers on the plurality of pixel electrodes by a wet film formation method;
Over the plurality of light emitting layers, the upper surface excluding the partial region of the first feeding auxiliary electrode layer and the upper surface on the second feeding auxiliary electrode layer continuously covering the common electrode layer by sputtering or CVD ( And a step of forming by a Chemical Vapor Deposition method.

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