Self-emitting panel and method for manufacturing the same

Abstract

To provide a self-luminous panel that forms a functional layer by a wet process, and can improve the luminous efficiency and life by making the film thickness of the functional layer uniform regardless of the definition and size of the panel, and a manufacturing method thereof.SOLUTION: A self-luminous panel includes a substrate, a drive circuit layer arranged on the substrate, an interlayer insulation layer arranged on the drive circuit layer, and a light emitting element layer arranged on the interlayer insulating layer and including a plurality of light emitting elements, the drive circuit layer includes a projecting portion protruding toward the interlayer insulating layer, and the light emitting element layer includes a plurality of pixel electrodes formed for each light emitting element, a functional layer composed of a coating film arranged on each of the pixel electrodes, a counter electrode arranged on the functional layer, and an intrapixel insulating layer arranged between at least a part of the pixel electrodes and the counter electrode, and when the light emitting element including the intrapixel insulating layer is viewed in a plan view, a region where the insulating layer in the pixel exists includes the entire region not above the projecting portion.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to a self-luminous panel using light-emitting elements that utilize the electroluminescence phenomenon or the quantum dot effect, and a manufacturing method thereof. [Background technology]

[0002] In recent years, self-luminous panels using light-emitting elements such as organic electroluminescence (EL) elements that utilize the electroluminescence phenomenon of organic materials and QLEDs that utilize the quantum dot effect have become increasingly popular.

[0003] The light-emitting element has a structure in which at least a light-emitting layer is sandwiched between an anode and a cathode. Currently, as a method for efficiently forming a functional layer including a light-emitting layer, a wet process is used to apply an ink containing a functional material. In the wet process, the manufacturing equipment can be made smaller than a vacuum deposition device, and there is no need to use a shadow mask used when depositing a functional material. Therefore, there is no need for work such as aligning the shadow mask, and it is easy to produce a large panel or a large substrate with a mixed panel size considering mass production, and it has a feature suitable for efficient panel production. In addition, unlike the deposition method, the wet process improves the efficiency of use of functional materials such as expensive light-emitting materials, thereby making it possible to reduce panel production costs.

[0004] In addition, in these self-emitting panels, in order to facilitate control of each self-emitting element, it is common to form a driving circuit using a TFT (Thin Film Transistor) or the like as a thin film, and stack the driving circuit layer and the light-emitting element layer in the film thickness direction of the self-emitting panel to make an electrical connection through a contact hole (see, for example, Patent Documents 1, 2 and 3). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2016-40764 A [Patent Document 2] International Publication No. 2015 / 118598 [Patent Document 3] JP 2016-167400 A Summary of the Invention [Problem to be solved by the invention]

[0006] When a light emitting element layer is laminated on a driving circuit layer, the lower surface of the light emitting element layer is flattened by an interlayer insulating layer made of an insulating material in order to provide electrical insulation and flatten the physical unevenness. However, if the unevenness of the driving circuit layer is large, the flatness of the upper surface of the interlayer insulating layer may not be sufficient. In addition, when the functional layer of the light emitting element is formed by a wet process, the tolerance margin for unevenness of the upper surface of the interlayer insulating layer becomes smaller due to the improvement of the resolution and increase in size of the panel. Therefore, there is a problem that it is difficult to achieve both the improvement of the resolution and increase in size of the panel and the improvement of the light emitting efficiency and lifespan by the uniform film thickness of the functional layer.

[0007] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a self-emitting panel in which a functional layer is formed by a wet process, which can improve luminous efficiency and lifespan by making the film thickness of the functional layer uniform regardless of the resolution or size of the panel, and a manufacturing method thereof. [Means for solving the problem]

[0008] A self-emitting panel according to one embodiment of the present disclosure comprises a substrate, a driving circuit layer arranged on the substrate, an interlayer insulating layer arranged on the driving circuit layer, and a light-emitting element layer arranged on the interlayer insulating layer and including a plurality of light-emitting elements, the driving circuit layer including wiring and a semiconductor circuit corresponding to the light-emitting element and having a protrusion protruding toward the interlayer insulating layer, the light-emitting element layer including a plurality of pixel electrodes formed for each of the light-emitting elements, a functional layer consisting of a coating film arranged above each of the plurality of pixel electrodes, a counter electrode arranged above the functional layer, and an intra-pixel insulating layer arranged between at least some of the pixel electrodes and the counter electrode, when the light-emitting element including the intra-pixel insulating layer is viewed in a plan view, the light-emitting element includes at least a portion of the region above the protrusion as a light-emitting region, and the region of the intra-pixel insulating layer, which is a non-light-emitting region, includes the entire region not above the protrusion. Effect of the Invention

[0009] In the self-emitting panel according to one embodiment of the present disclosure, the region above the pixel electrode that is not above the protrusion is a non-emitting region, and a portion of the region above the protrusion is a emitting region. Therefore, it is sufficient to make the film thickness of the functional layer uniform in the emitting region that is a portion above the protrusion, and it is not necessary to homogenize the film thickness of the functional layer between the emitting region that is a portion above the protrusion and the other non-emitting regions. In other words, even if the upper surface of the insulating layer or the upper surface of the pixel electrode is not flat due to the protrusion, it is possible to easily achieve a uniform film thickness of the functional layer in the emitting region, thereby improving the luminous efficiency and lifespan. [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic diagram of a display device 1 including a self-emission panel 10 according to an embodiment. [Diagram 2] 2 is a schematic diagram showing a circuit configuration of each sub-pixel of a self-emission panel 10 according to an embodiment. FIG. [Diagram 3] 1 is a schematic plan view of a self-emission panel 10 according to an embodiment. [Figure 4] 4 is a partial cross-sectional view of the self-emission panel 10 according to the first embodiment, which corresponds to the cross-section AA in FIG. [Diagram 5] 1 is a schematic transparent plan view showing the positional relationship between a pixel electrode 13, an intra-pixel insulating layer 30, and a protrusion 1121 in an organic EL element 2 according to the first embodiment. [Figure 6] 1A is a photograph of a comparative example of a self-emitting panel not having an intra-pixel insulating layer 30 when in operation, and FIG. 1B is a graph showing the functional layer thickness distribution of an organic EL element of a comparative example not having an intra-pixel insulating layer 30. [Figure 7] 1A is a scatter plot showing the relationship between chromaticity and efficiency of an organic EL element according to a comparative example that does not have an intra-pixel insulating layer 30; FIG. 1B is a graph showing the filter characteristics and external light reflection spectrum of an organic EL element according to a comparative example that does not have an intra-pixel insulating layer 30; FIG. 1C is a graph showing the degree of current concentration of an organic EL element according to a comparative example that does not have an intra-pixel insulating layer 30; and FIG. 1D is a graph showing the lifetime of an organic EL element according to a comparative example that does not have an intra-pixel insulating layer 30. [Figure 8] 13(a) and 13(b) are cross-sectional photographs of a self-emitting panel according to a comparative example that does not have an intra-pixel insulating layer 30. [Figure 9] FIG. 1 is a partial cross-sectional view showing a schematic diagram of a part of a manufacturing process of an organic EL panel according to a first embodiment, in which (a) shows a state in which a TFT layer and an interlayer insulating layer are formed on a substrate, (b) shows a state in which a pixel electrode material is formed on the interlayer insulating layer, (c) shows a state in which a pixel electrode is formed, (d) shows a state in which a pixel insulating material layer is formed on the interlayer insulating layer and the pixel electrode, and (e) shows a state in which a pixel insulating layer is formed on the pixel electrode. [Figure 10] FIG. 1 is a partial cross-sectional view showing a schematic diagram of a part of a manufacturing process of an organic EL panel according to a first embodiment, in which (a) shows a state in which a partition material layer is formed on an interlayer insulating layer, a pixel electrode, and an intra-pixel insulating layer, (b) shows a state in which a partition is formed, (c) shows a state in which a hole injection layer is formed on a pixel electrode, and (d) shows a state in which a hole transport layer is formed on the hole injection layer. [Figure 11]FIG. 1 is a partial cross-sectional view showing a schematic diagram of a part of a manufacturing process of an organic EL panel according to a first embodiment, in which (a) shows a state in which a light-emitting layer is formed on a hole-transport layer, (b) shows a state in which an electron-transport layer is formed on the light-emitting layer and the partition layer, and (c) shows a state in which an electron-injection layer is formed on the electron-transport layer. [Figure 12] 1A and 1B are partial cross-sectional views each showing a schematic diagram of a part of a manufacturing process of an organic EL panel according to embodiment 1. FIG. 1A is a partial cross-sectional view showing a state in which a counter electrode is formed on an electron injection layer, and FIG. 1B is a partial cross-sectional view showing a state in which a sealing layer is formed on the counter electrode. [Figure 13] 4 is a flowchart showing a manufacturing process of the organic EL panel according to the first embodiment. [Figure 14] 4 is a partial cross-sectional view of a self-emission panel 10A according to the second embodiment, which corresponds to the cross-section AA in FIG. [Figure 15] 1 is a schematic transparent plan view showing the positional relationship between a pixel electrode 13, an intra-pixel insulating layer 30, and a protrusion 1121 in an organic EL element 2A according to Embodiment 2. FIG. [Figure 16] FIG. 11 is a partial cross-sectional view showing a schematic diagram of a part of a manufacturing process of an organic EL panel according to embodiment 2, in which (a) shows a state in which an intra-pixel insulating material layer is formed on an interlayer insulating layer and a pixel electrode, and (b) shows a state in which an intra-pixel insulating layer is formed on the pixel electrode. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] <<How one aspect of the present disclosure was arrived at>> In a self-emitting panel having a plurality of light-emitting elements such as a display panel or an illumination panel, a multi-layer structure is generally used in which a driving circuit layer using TFTs or the like is formed on a substrate, and a light-emitting element layer is formed above the driving circuit layer. With such a configuration, it is possible to simplify the control wiring for connecting the self-emitting panel to a control circuit outside the panel, without the need to provide control wiring for each light-emitting element. In particular, by adopting a configuration in which a corresponding driving circuit is disposed below the light-emitting element, the electrical connection between the driving circuit and the light-emitting element can be achieved by simple wiring in the film thickness direction such as a contact hole, which makes the design easier and simplifies the manufacturing process.

[0012] On the other hand, in order to electrically insulate the driving circuit layer from the light emitting element layer, an interlayer insulating layer is required between the driving circuit layer and the light emitting element layer. In addition, since the light emitting element layer is formed on the interlayer insulating layer, the upper surface of the interlayer insulating layer needs to be flat. Therefore, in the past, the interlayer insulating layer was formed of a resin layer having a thickness of about several μm in order to maintain the flatness of its upper surface.

[0013] When the functional layer of the light-emitting element is formed by a wet process, the film shape of the functional layer is affected by the top surface shape of the interlayer insulating layer, and the higher the flatness of the top surface shape of the interlayer insulating layer, the more uniform the film thickness of the functional layer becomes, and current concentration and the like are suppressed, improving the light-emitting efficiency and life of the light-emitting element. However, the inventors have found a problem that the flatness of the interlayer insulating layer may be insufficient when the definition or size of the self-emitting panel is improved. When the definition of the self-emitting panel is improved, the area of ​​each light-emitting element becomes smaller, so the area over which the ink for forming the functional layer wets and spreads becomes smaller, and the film thickness of the functional layer may not be averaged. In addition, when the size of the self-emitting panel increases, the vapor pressure of the solvent contained in the ink is likely to be uneven between the center and periphery of the panel during the drying process of the ink for forming the functional layer, and the film thickness of the functional layer may be biased. In other words, when the definition or size of the self-emitting panel is improved, a higher flatness is required on the top surface of the interlayer insulating layer in order to uniform the film thickness of the functional layer. On the other hand, the upper surface of the interlayer insulating layer is affected by the unevenness of the upper surface of the drive circuit layer, and in particular, the arrangement and shape of the electrodes and wiring at the top of the drive circuit layer affect the shape of the upper surface of the drive circuit layer. Therefore, when the definition or size of the self-emitting panel is improved, the insufficient flatness of the interlayer insulating layer causes unevenness in the film thickness of the functional layer, which can lead to reduced luminous efficiency and reduced lifespan due to current concentration, etc.

[0014] Therefore, the inventors have investigated techniques for improving the uniformity of the film thickness of the functional layer, regardless of the resolution or size of the self-emitting panel, and have arrived at the aspects of the present disclosure.

[0015] <Mode of Disclosure> A self-emitting panel according to at least one embodiment of the present disclosure comprises a substrate, a driving circuit layer arranged on the substrate, an interlayer insulating layer arranged on the driving circuit layer, and a light-emitting element layer arranged on the interlayer insulating layer and including a plurality of light-emitting elements, wherein the driving circuit layer includes wiring and a semiconductor circuit corresponding to the light-emitting element and has a protrusion protruding toward the interlayer insulating layer, and the light-emitting element layer includes a plurality of pixel electrodes formed for each of the light-emitting elements, a functional layer made of a coating film arranged above each of the plurality of pixel electrodes, a counter electrode arranged above the functional layer, and an intra-pixel insulating layer arranged between at least some of the pixel electrodes and the counter electrode, wherein when the light-emitting element including the intra-pixel insulating layer is viewed in a plane, the light-emitting element includes at least a portion of the area above the protrusion as a light-emitting area, and the area of ​​the intra-pixel insulating layer, which is a non-light-emitting area, includes the entire area not above the protrusion.

[0016] A method for manufacturing a self-emitting panel according to at least one aspect of the present disclosure includes forming a drive circuit layer on a substrate, forming an insulating layer on the drive circuit layer, forming a plurality of pixel electrodes, forming an intra-pixel insulating layer in a first region above the pixel electrodes but not above the protrusion, forming a functional layer by application above the pixel electrodes including above the intra-pixel insulating layer, and forming a counter electrode above the functional layer.

[0017] In the self-emitting panel according to at least one embodiment of the present disclosure, or the self-emitting panel according to the method for manufacturing the self-emitting panel, the region above the pixel electrode that is not above the protrusion is a non-emitting region, and a part of the region above the protrusion is a emitting region. Therefore, it is sufficient to make the film thickness of the functional layer uniform in the emitting region that is a part above the protrusion, and it is not necessary to homogenize the film thickness of the functional layer between the emitting region that is a part above the protrusion and the other non-emitting regions. In other words, even if the upper surface of the insulating layer or the upper surface of the pixel electrode is not flat due to the protrusion, it is possible to easily achieve a uniform film thickness of the functional layer in the emitting region, thereby improving the luminous efficiency and lifespan.

[0018] Furthermore, at least one other self-emitting panel of the present disclosure comprises a substrate, a driving circuit layer arranged on the substrate, an interlayer insulating layer arranged on the driving circuit layer, and a light-emitting element layer arranged on the interlayer insulating layer and including a plurality of light-emitting elements, the driving circuit layer including wiring and a semiconductor circuit corresponding to the light-emitting element and having a protrusion protruding toward the interlayer insulating layer, the light-emitting element layer including a plurality of pixel electrodes formed for each of the light-emitting elements, a functional layer consisting of a coating film arranged above each of the plurality of pixel electrodes, a counter electrode arranged above the functional layer, and an intra-pixel insulating layer arranged between at least some of the pixel electrodes and the counter electrode, when the light-emitting element including the intra-pixel insulating layer is viewed in a plan view, the light-emitting element includes at least a portion of the region not above the protrusion as a light-emitting region, and the presence region of the intra-pixel insulating layer, which is a non-light-emitting region, includes the entire area above the protrusion.

[0019] Furthermore, at least one other method for manufacturing a self-emitting panel of the present disclosure includes forming a drive circuit layer on a substrate, forming an insulating layer on the drive circuit layer, forming a plurality of pixel electrodes, forming an intra-pixel insulating layer in a second region above the pixel electrodes and above the protrusion, forming a functional layer by application above the pixel electrodes including above the intra-pixel insulating layer, and forming a counter electrode above the functional layer.

[0020] In the self-emitting panel according to at least one embodiment of the present disclosure, or the self-emitting panel according to the method for manufacturing the self-emitting panel, the region above the protrusion above the pixel electrode is a non-emitting region, and a part of the region not above the protrusion is a emitting region. Therefore, it is sufficient to make the film thickness of the functional layer uniform in the emitting region that is not a part above the protrusion, and it is not necessary to homogenize the film thickness of the functional layer between the emitting region that is not a part above the protrusion and the other non-emitting regions. In other words, even if the upper surface of the insulating layer or the upper surface of the pixel electrode is not flat due to the protrusion, it is possible to easily achieve a uniform film thickness of the functional layer in the emitting region, thereby improving the luminous efficiency and lifespan.

[0021] In addition, in the self-emitting panel according to at least one aspect of the present disclosure, the drive circuit layer may be composed of a plurality of layers, and the protrusion may be a layer of the drive circuit layer on the opposing electrode side.

[0022] As a result, when the control circuit layer is made up of multiple layers, there is little need to address the lower layers, which have little effect on the top surface shape of the insulating portion, so it is possible to address only the upper layers, which have a large effect on the top surface shape of the insulating portion.

[0023] Furthermore, the self-emitting panel according to at least one aspect of the present disclosure may include a coating film between the intra-pixel insulating layer and the counter electrode, the coating film being made of the same material as the functional layer.

[0024] This allows the ink to be applied across the light-emitting region and the non-light-emitting region where the pixel insulating layer is present during the formation of the functional layer, eliminating the need to exclude the pixel insulating layer from the region where the functional layer is formed, thereby facilitating the formation of the functional layer.

[0025] Furthermore, the self-emitting panel according to at least one aspect of the present disclosure may further include a plurality of elongated partition walls arranged on the interlayer insulating layer and juxtaposed between the pixel electrodes, and the functional layer may be arranged in the gap between a pair of adjacent partition walls.

[0026] This makes it possible to easily form the functional layer using the partition wall.

[0027] In the self-emission panel according to at least one aspect of the present disclosure, the intra-pixel insulating layer and the partition wall may be formed from the same material.

[0028] This makes it possible to simultaneously manufacture the partition walls and the insulating layer within the pixels in a single process, facilitating the manufacture of self-emitting panels.

[0029] In addition, in a self-emitting panel according to at least one aspect of the present disclosure, the liquid repellency of the material of the pixel insulating layer to the material ink of the functional layer may be lower than the liquid repellency of the material of the partition to the material ink of the functional layer.

[0030] This ensures high liquid repellency of the partition when the functional layer is formed, and prevents the film thickness of the functional layer from becoming non-uniform due to liquid repellency at the outer edge of the intra-pixel insulating layer on the pixel electrode.

[0031] Furthermore, the self-emitting panel according to at least one aspect of the present disclosure may further include a plurality of pixel regulating layers arranged on the interlayer insulating layer and juxtaposed between the pixel electrodes in the gaps between a pair of adjacent partitions, and the pixel insulating layer and the pixel regulating layers may be formed from the same material.

[0032] This allows the functional layer to be formed as a coating film spanning multiple light-emitting elements, which improves the uniformity of the functional layer's thickness and makes it possible to simultaneously form the pixel regulation layer and intra-pixel insulation layer in a single process, simplifying the manufacturing process.

[0033] First Embodiment Hereinafter, an embodiment of a display device using an organic EL panel as a self-emitting panel according to the present disclosure (hereinafter simply referred to as a "display device") will be described.

[0034] <Display device configuration> (1) Circuit configuration of display device 1 FIG. 1 is a block diagram showing a circuit configuration of a display device 1. As shown in FIG.

[0035] As shown in FIG. 1, the display device 1 includes an organic EL panel 10 and a drive control circuit section 200 connected thereto.

[0036] The organic EL panel 10 is an organic EL (Electro Luminescence) panel that utilizes the electroluminescence phenomenon of organic materials, and is configured such that a plurality of organic EL elements are arranged, for example, in a matrix (rows and columns).

[0037] The drive control circuit section 200 is made up of four drive circuits 210 and a control circuit 220.

[0038] (2) Circuit configuration of organic EL panel 10 In the organic EL 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 sub-pixels 100se that emit light in three colors, R (red), G (green), and B (blue). The circuit configuration of each sub-pixel 100se will be described with reference to FIG. 2.

[0039] FIG. 2 is a circuit diagram showing a circuit configuration in an organic EL element 2 corresponding to each sub-pixel 100se of an organic EL panel 10 used in the display device 1. As shown in FIG.

[0040] 2, in the organic EL panel 10 according to the present embodiment, each sub-pixel 100se includes two transistors Tr1 and Tr2, one capacitor C, and an organic EL element portion EL as a light-emitting portion. The transistor Tr1 is a drive transistor, and the transistor Tr2 is a switching transistor.

[0041] The gate G2 of the switching transistor Tr2 is connected to the scan line Vscn, the source S2 is connected to the data line Vdat, and the drain D2 of the switching transistor Tr2 is connected to the gate G1 of the driving transistor Tr1.

[0042] The drain D1 of the driving transistor Tr1 is connected to a power supply line Va, and the source S1 is connected to a pixel electrode (anode) of the organic EL element unit EL. A common electrode (counter electrode: cathode) in the organic EL element unit EL is connected to a ground line Vcat.

[0043] A first terminal 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 a second terminal of the capacitor C is connected to the power supply line Va.

[0044] In the organic EL panel 10, a single unit pixel 100e is formed by combining a plurality of adjacent sub-pixels 100se (for example, three sub-pixels 100se emitting red (R), green (G), and blue (B) light), and the unit pixels 100e are distributed to form a pixel region.

[0045] A gate line is drawn from the gate G2 of each subpixel 100se and connected to a scan line Vscn connected from outside the organic EL panel 10. Similarly, a source line is drawn from the source S2 of each subpixel 100se and connected to a data line Vdat connected from outside the organic EL panel 10.

[0046] Furthermore, the power supply line Va of each sub-pixel 100se and the ground line Vcat of each sub-pixel 100se are aggregated and connected to the power supply line and ground line of the display device 1.

[0047] The drive circuit for each organic EL element is not limited to the above, and may have another configuration.

[0048] (3) Structure of OLED panel 10 3 is a schematic plan view of an enlarged portion of an organic EL panel 10. The organic EL panel 10 is partitioned in a matrix by partition walls (column banks) 14 that partition the substrate in the row direction (X direction) and define coating regions, and pixel restriction layers (row banks) 141 that partition the substrate in the column direction (Y direction). The regions partitioned by the partition walls 14 and the pixel restriction layers 141 respectively constitute sub-pixels 100R, 100G, and 100B, and the sub-pixels 100R, 100G, and 100B constitute a pixel P. The sub-pixels 100R, 100G, and 100B are formed in coating regions CR, CG, and CB that are partitioned by two partition walls 14 adjacent to each other in the X direction, respectively.

[0049] (4) Structure of organic EL element 2 Fig. 4 is a schematic cross-sectional view of a portion of the organic EL panel 10, corresponding to the cross section taken along line AA in Fig. 3. Each of the sub-pixels 100R, 100G, and 100B of the organic EL panel 10 is composed of an organic EL element 2(R), 2(G), and 2(B), which is a self-luminous element. Hereinafter, when there is no need to distinguish between the organic EL elements 2(R), 2(G), and 2(B), they will be described as the organic EL element 2.

[0050] The organic EL panel 10 includes, in order from the bottom, a substrate 11, an interlayer insulating layer 12, and a partition wall 14. In an opening 14a defined by two partition walls adjacent in the X direction, a pixel electrode 13, an intra-pixel insulating layer 30, a hole injection layer 15, a hole transport layer 16, and a light-emitting layer 17 are provided, and an electron transport layer 18, an electron injection layer 19, a counter electrode 20, and a sealing layer 21 are provided as common layers. The substrate 11 includes a TFT layer 112 formed as a multilayer structure on a base material 111, and the boundary between the top layer and the interlayer insulating layer 12 is not flat, and a protruding portion 1121, which is an upper portion of the TFT, a wiring or an electrode, protrudes toward the interlayer insulating layer 12. Of these, the portion from the pixel electrode 13 to the counter electrode 20 constitutes an organic EL element 2.

[0051] <Components of an organic EL element> (1) Circuit Board The substrate 11 includes a base material 111 made of an insulating material and a TFT (Thin Film Transistor) layer 112. A driving circuit is formed in the TFT layer 112 for each subpixel. The TFT layer 112 has a multi-layer structure and a structure having a gap, and the interlayer insulating layer 12 protrudes downward into the gap. That is, the interface between the substrate 11 and the interlayer insulating layer 12 is not flat, and the protruding portion of the substrate 11 and the recessed portion of the interlayer insulating layer 12 are engaged with each other without any gaps. The substrate 111 may be, for example, a glass substrate, a quartz substrate, a silicon substrate, a metal substrate such as molybdenum sulfide, copper, zinc, aluminum, stainless steel, magnesium, iron, nickel, gold, or silver, a semiconductor substrate such as gallium arsenide, or a plastic substrate.

[0052] As the plastic material, either a thermoplastic resin or a thermosetting resin may be used.

[0053] (2) Interlayer insulation layer The interlayer insulating layer 12 is formed on the substrate 11. The interlayer insulating layer 12 is made of a resin material and serves to flatten steps on the upper surface of the TFT layer 112. Examples of the resin material include a positive-type photosensitive material. Examples of such photosensitive materials include acrylic resin, polyimide resin, siloxane resin, and phenol resin. As described above, the boundary between the interlayer insulating layer 12 and the TFT layer 112 is not flat, and the top layer of the TFT layer 112 protrudes toward the pixel electrode 13 as a protrusion 1121. Although not shown in the cross-sectional view of FIG. 3, the interlayer insulating layer 12 has a contact hole formed for each subpixel.

[0054] (3) Pixel electrode The pixel electrode 13 includes a metal layer made of a light-reflective metal material, and is formed on the interlayer insulating layer 12. The pixel electrode 13 is provided for each sub-pixel, and is electrically connected to the TFT layer 112 through a contact hole (not shown).

[0055] In this embodiment, the pixel electrode 13 functions as an anode.

[0056] Specific examples of metal materials having light reflectivity include Ag (silver), Al (aluminum), aluminum alloys, Mo (molybdenum), APC (an alloy of silver, palladium, and copper), ARA (an alloy of silver, rubidium, and gold), MoCr (an alloy of molybdenum and chromium), MoW (an alloy of molybdenum and tungsten), and NiCr (an alloy of nickel and chromium).

[0057] The pixel electrode 13 may be composed of a metal layer alone, or may have a laminated structure in which a layer made of a metal oxide such as ITO (indium tin oxide) or IZO (indium zinc oxide) is laminated on a metal layer.

[0058] (4) Intra-pixel insulation layer The pixel insulating layer 30 is interposed between the pixel electrode 13 and the hole injection layer 15 in the area other than above the protrusion 1121 and in its vicinity, and is intended to make the area where the pixel insulating layer 30 exists in a planar view a non-light-emitting area.

[0059] 5 is a schematic plan view showing the relationship between the pixel insulating layer 30 and the pixel electrode 13, the protrusion 1121, the partition wall 14, and the pixel restriction layer 141, and shows only the pixel electrode 13, the protrusion 1121, the partition wall 14, and the pixel restriction layer 141 in a see-through state as viewed from the top surface side (sealing layer 21 side) of the organic EL panel 10. As shown in FIG. 5(a), a part of the periphery of the pixel electrode 13 is covered by the partition wall 14 and the pixel restriction layer 141, and the opening 13a is exposed. As shown in FIG. 5(b), the pixel insulating layer 30 is formed so as to cover the entire first region 13ap of the opening 13a that is not on the protrusion 1121, and the region of the second region 13aq that is on the protrusion 1121 and is in contact with the first region 13ap. 4, on the upper surface of the interlayer insulating layer 12, the second region 13aq on the protruding portion 1121 and its periphery have a shape convex upward relative to the first region 13ap not on the protruding portion 1121. The intra-pixel insulating layer 30 has a function of making the film thickness uniform within the light-emitting region by making the first region 13ap and its periphery a non-light-emitting region within the light-emitting element and making only the second region 13aq on the protruding portion 1121 a light-emitting region.

[0060] The upper surface of the intra-pixel insulating layer 30 is lower than the upper surface of the partition wall 14 and is preferably at the same height as the upper surface of the intra-pixel regulation layer 141 or lower than the upper surface of the intra-pixel regulation layer 141 .

[0061] The material of the pixel insulating layer 30 has insulating properties. The material of the pixel insulating layer 30 may have lyophilicity with respect to the ink for forming the functional layer. The pixel insulating layer 30 is made of, for example, an insulating organic material, such as acrylic resin, polyimide resin, siloxane resin, or phenolic resin. The material of the pixel insulating layer 30 may contain a dye or pigment that absorbs the light emitted by the organic EL element 2. The pixel insulating layer 30 absorbs light of the same wavelength as the light emitted by the organic EL element 2, so that the non-light-emitting region in which the pixel insulating layer 30 is disposed can suppress a decrease in color purity of the organic EL panel 10 caused by reflection of external light or reflection of light emitted by the light-emitting layer 17.

[0062] The intra-pixel insulating layer 30 and the pixel regulating layer 141 may be made of the same material, and may be formed at the same time.

[0063] (5) Partition wall and pixel control layer The partitions 14 partition the pixel electrodes 13 arranged for each sub-pixel above the substrate 11 into columns in the X direction (see FIG. 3), and have a line bank shape extending in the Y direction between the sub-pixel columns CR, CG, and CB arranged in the X direction. The partitions 14 are insulating, and at least their surfaces are liquid-repellent with respect to the ink for forming the functional layer. The partitions 14 are made of, for example, an insulating organic material (for example, an acrylic resin, a polyimide resin, a siloxane resin, a phenolic resin, etc.). In this embodiment, a phenolic resin is used. The partitions 14 may contain an additive that has liquid repellency, such as a fluorine-based surfactant, or may be surface-treated. The organic EL elements 2 are formed in the openings 14a defined by two partitions 14 adjacent to each other in the X direction.

[0064] The pixel regulating layer 141 divides the pixel electrodes 13 adjacent to each other in the Y direction in the opening 14a, and serves to suppress discontinuity of the light emitting layer 17 in the subpixel columns CR, CG, and CB, and to improve electrical insulation between the pixel electrodes 13 and the counter electrode 20. The pixel regulating layer 141 is insulating. The material of the pixel regulating layer 141 may have lyophilicity with respect to the ink for forming the functional layer. The pixel regulating layer 141 is made of, for example, an insulating organic material, such as acrylic resin, polyimide resin, siloxane resin, or phenol resin. As described above, the intra-pixel insulating layer 30 and the pixel regulating layer 141 may be made of the same material, or may be formed simultaneously.

[0065] (6) Hole injection layer The hole injection layer 15 is provided on the pixel electrode 13 for the purpose of promoting the injection of holes from the pixel electrode 13 to the light emitting layer 17. The hole injection layer 15 is a layer containing, for example, a low molecular weight organic compound such as copper phthalocyanine (CuPc) or a polymer material such as polyethylenedioxythiophene / polystyrenesulfonic acid (PEDOT / PSS). In the present embodiment, the hole injection layer 15 is a coating film formed by a wet method. In addition, when other functional layers included in the organic EL element 2 are coating films, the hole injection layer 15 may be a vapor deposition film, and may be, for example, a layer containing an oxide of a transition metal such as Ag (silver), Mo (molybdenum), Cr (chromium), V (vanadium), W (tungsten), Ni (nickel), or Ir (iridium). In this case, each of the intra-pixel insulating layer 30, the pixel regulating layer 141, and the partition wall 14 may be formed on the hole injection layer 15. The hole injection layer 15 may have a multi-layer structure in which a coating layer containing an organic material is laminated on a deposition layer containing an oxide of a transition metal. In this case, the pixel insulating layer 30, the pixel regulating layer 141, and the partition 14 may each be on the deposition layer, and the pixel insulating layer 30 may be formed between the deposition layer and the coating layer.

[0066] (7) Hole transport layer The hole transport layer 16 has a function of transporting holes injected from the hole injection layer 15 to the light emitting layer 17. In the present embodiment, the hole transport layer 16 is a coating film. Examples of materials for the hole transport layer 16 include arylamine derivatives, fluorene derivatives, spiro derivatives, carbazole derivatives, pyridine derivatives, pyrazine derivatives, pyrimidine derivatives, triazine derivatives, quinoline derivatives, phenanthroline derivatives, phthalocyanine derivatives, porphyrin derivatives, silole derivatives, oligothiophene derivatives, condensed polycyclic aromatic derivatives, and metal complexes.

[0067] (8) Light-emitting layer The light-emitting layer 17 is formed in the opening 14a, and has a function of emitting light of each color R, G, and B by recombination of holes and electrons. Known materials can be used as the material of the light-emitting layer 17.

[0068] When the light-emitting element 2 is an organic EL element, examples of the organic light-emitting material contained in the light-emitting layer 17 include oxinoid compounds, perylene compounds, coumarin compounds, azacoumarin compounds, oxazole compounds, oxadiazole compounds, perinone compounds, pyrrolopyrrole compounds, naphthalene compounds, anthracene compounds, 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, and the like. Fluorescent substances such as fluorescein compounds, stilbene compounds, diphenylquinone compounds, styryl compounds, butadiene compounds, dicyanomethylenepyran compounds, dicyanomethylenethiopyran compounds, fluorescein compounds, pyrylium compounds, thiapyrylium compounds, selenapyrylium compounds, telluropyrylium compounds, aromatic aldadiene compounds, oligophenylene compounds, thioxanthene compounds, cyanine compounds, acridine compounds, metal complexes of 8-hydroxyquinoline compounds, metal complexes of 2-bipyridine compounds, complexes of Schiff salts and group III metals, oxine metal complexes, and rare earth complexes can be used. Also, known phosphorescent substances such as phosphorescent metal complexes such as tris(2-phenylpyridine)iridium can be used. Also, the light-emitting layer 17 may be formed using polymer compounds such as polyfluorene and its derivatives, polyphenylene and its derivatives, or polyarylamine and its derivatives, or a mixture of the low molecular weight compounds and the polymer compounds. The light-emitting element 2 may be a quantum-dot light-emitting element (QLED; Quantum-dot Light Emitting Diode), and the light-emitting layer 17 may be made of a material having a quantum dot effect.

[0069] In this embodiment, the light emitting layer 17 is a coating film formed by coating with ink.

[0070] (9)Electron transport layer The electron transport layer 18 has a function of transporting electrons from the counter electrode 20 to the light emitting layer 17. The electron transport layer 18 is made of an organic material having high electron transport properties.

[0071] Examples of the organic material used for the electron transport layer 18 include π-electron low molecular weight organic materials such as oxadiazole derivatives (OXD), triazole derivatives (TAZ), and phenanthroline derivatives (BCP, Bphen).

[0072] (10)Electron injection layer The electron injection layer 19 is provided on the electron transport layer 18 in common to a plurality of pixels, and has the function of promoting the injection of electrons from the counter electrode 20 to the light emitting layer 17 .

[0073] The electron injection layer 19 is formed, for example, by doping an organic material having electron transport properties with a metal material that improves electron injection properties. Here, doping refers to dispersing metal atoms or metal ions of the metal material approximately evenly in the organic material, and more specifically, to forming a single phase containing the organic material and a trace amount of the metal material. For example, an alkali metal, an alkaline earth metal, or a rare earth metal is selected as the metal material. In this embodiment, Yb is selected.

[0074] The electron injection layer 19 is formed by, for example, forming a film of a material such as an oxadiazole derivative, a triazole derivative, or a phenanthroline derivative, and a metal material by co-evaporation in common to a plurality of pixels.

[0075] (11) Counter electrode The counter electrode 20 is formed on the electron injection layer 19 and is common to a plurality of pixels, and functions as a cathode.

[0076] In this embodiment, the counter electrode 20 has both translucency and electrical conductivity, and includes at least one of a metal layer made of a metal material and a metal oxide layer made of a metal oxide. To ensure translucency, the thickness of the metal layer is about 1 nm to 50 nm. Examples of materials for the metal layer include Ag, a silver alloy mainly composed of Ag, Al, and an Al alloy mainly composed of Al.

[0077] The counter electrode 20 may be composed of a metal layer alone or a metal oxide layer alone, or may have a laminated structure in which a metal oxide layer is laminated on a metal layer, or a laminated structure in which a metal layer is laminated on a metal oxide layer.

[0078] (12) Sealing layer A sealing layer 21 is provided on the counter electrode 20. The sealing layer 21 has a function of preventing impurities (water, oxygen) from penetrating into the counter electrode 20, the electron injection layer 19, the electron transport layer 18, the light emitting layer 17, etc. from the opposite side of the substrate 11, and suppressing deterioration of these layers due to impurities. The sealing layer 21 is formed using a light-transmitting material such as silicon nitride (SiN) or silicon oxynitride (SiON). In addition, a sealing resin layer made of a resin material such as an acrylic resin or an epoxy resin may be provided on a layer formed using a material such as silicon nitride (SiN) or silicon oxynitride (SiON).

[0079] In the present embodiment, since the organic EL panel 10 is of a top emission type, the sealing layer 21 needs to be made of a light-transmitting material.

[0080] (13)Other 4, a color filter or a polarizing sheet having a glass substrate as a base material may be attached via an adhesive onto the sealing layer 21. By attaching these, the hole transport layer 16, the light emitting layer 17, the electron transport layer 18, and the electron injection layer 19 can be further protected from external moisture, air, and the like.

[0081] <Uniformity of film thickness> The effect of the protrusion 1121 on the film thickness of the functional layer will be described in detail below.

[0082] (1) Emission intensity and film thickness FIG. 6(a) is a photograph of the luminance of each element in a light-emitting state in one pixel of an organic EL panel (hereinafter, referred to as "Comparative Example") manufactured without providing an intra-pixel insulating layer 30 with respect to the arrangement of structural members shown in FIG. 5(a). As shown in FIG. 6(a), in the Comparative Example, the emission luminance is higher in the region (region 13aq) on the protrusion 1121 than in the region (region 13ap) not on the protrusion 1121. This is because the film thickness of the functional layer is smaller in the region 13aq on the protrusion 1121 than in the region 13ap not on the protrusion 1121. FIG. 6(b) is a graph showing the difference values ​​of the film thickness of the light-emitting layer 17 at positions A, B, C, and D in FIG. 6(a), with the film thickness at position A set to 0. Incidentally, "Hole injection layer + hole transport layer - 5 nm" corresponds to Comparative Example 1 in which the total thickness of the hole injection layer and the hole transport layer is 5 nm smaller than that of a conventional organic EL panel (hereinafter referred to as "Comparative Example 3") that is not affected by the protrusion 1121, and "Hole injection layer + hole transport layer + 5 nm" corresponds to Comparative Example 2 in which the total thickness of the hole injection layer and the hole transport layer is 5 nm larger than that of a conventional organic EL panel. As shown in FIG. 6(b), regardless of the value of the total thickness of the hole injection layer and the hole transport layer, the thickness of the light-emitting layer is about 15 to 30 nm larger at positions C and D than at positions A and B. This is considered to be because the height of the upper surface of the interlayer insulating layer 12 when the lower surface of the substrate 11 is used as a reference is different between positions A and B and positions C and D. That is, since positions A and B are above the protrusion 1121, the upper surface of the interlayer insulating layer 12 is raised and is higher than positions C and D that are not directly above the protrusion 1121. Therefore, when the functional layer is formed by the coating method, the ink used to form the functional layer is biased, and the functional layer is thick at the smaller height positions C and D, and thin at the larger height positions A and B. When the organic EL element emits light, the same voltage is applied to all of positions A to D, so current is concentrated at positions A and B, where the functional layer is thin and has low electrical resistance, and the brightness at positions A and B is higher than the brightness at positions C and D.

[0083] (2) Luminescence characteristics and life span FIG. 7(a) is a scatter plot in which the horizontal axis is the CIE X value of the emitted color and the vertical axis is the efficiency for the organic EL elements according to Comparative Examples 1, 2, and 3. In FIG. 7(a), the emission intensity and color characteristics of the organic EL element according to Comparative Example 3 are shown as data 301, and the emission intensity and color characteristics of the organic EL elements according to Comparative Examples 1 and 2 are shown as data 302. As shown in FIG. 7(a), the efficiency values ​​of Comparative Examples 1 and 2 are smaller for the same CIE X value than Comparative Example 3, and in particular, the efficiency is almost halved at a CIE X value of about 0.27. That is, the light-emitting element according to Comparative Example 1 or 2 requires about twice the emission intensity to obtain the same chromaticity as the light-emitting element of Comparative Example 3, and the light extraction efficiency is reduced.

[0084] FIG. 7(b) is a graph showing the relationship between the transmission spectrum of the color filter used for the green light emitting element and the external light reflection spectrum of the green light emitting organic EL elements according to Comparative Example 3 and Comparative Example 1. In FIG. 7(b), the external light reflection spectrum of the organic EL element according to Comparative Example 3 is shown as data 311, and the external light reflection spectrum of the organic EL element according to Comparative Example 1 is shown as data 312. As shown in FIG. 7(b), in the external light reflection spectrum of the organic EL element according to Comparative Example 3, the reflectance is at its lowest near 520 nm where the transmittance of the color filter is high, so that the external light reflection is sufficiently suppressed. In contrast, in the external light reflection spectrum of the organic EL element according to Comparative Example 1, the wavelength at which the reflectance is at its minimum is about 650 nm, which is shifted to the longer wavelength side than the transmittance peak of the color filter, so that the external light reflection cannot be sufficiently suppressed. The reason for this is thought to be that in Comparative Example 1, the film thickness of the functional layer is not uniform within the organic EL element, and therefore the optical path length from the pixel electrode 13 to the counter electrode 20 is not constant, resulting in a mixture of areas in which the optical resonator structure exhibits the effect of suppressing light reflection as designed, and areas in which the effect of suppressing light reflection is exhibited at longer wavelengths than designed due to a deviation in the optical path length.

[0085] FIG. 7(c) is a graph showing the spatial bias of the current in the light-emitting element, and shows the degree of current concentration above the protrusion 1121. Specifically, data 321, 322, and 323 show the current value per area above the protrusion 1121 as a relative value in Comparative Example 3, Comparative Example 1, and Comparative Example 2, respectively. As shown in FIG. 7(c), in Comparative Example 1 and Comparative Example 2, the current concentrates in the thin film portion of the functional layer above the protrusion 1121. Therefore, as shown in FIG. 7(d), the luminance is reduced and the deterioration is large, as shown in the life curve 332 corresponding to Comparative Example 1 and Comparative Example 2, compared to the life curve 331 corresponding to Comparative Example 3.

[0086] 8(a) and (b) are cross-sectional photographs of organic EL panels according to Comparative Example 1 and Comparative Example 2. As shown in Fig. 8(a) and (b), it can be seen that the upper surface of the interlayer insulating layer 12 and the upper surface of the pixel electrode 13 have a region 13aq above the protrusion 1121 that protrudes upward relative to a region 13ap that does not above the protrusion 1121. It can also be seen that in the region 13aq, the distance between the pixel electrode 13 and the counter electrode 20 is shorter than in the region 13ap, that is, the film thickness of the functional layer in the region 13aq is smaller than the film thickness of the functional layer in the region 13ap.

[0087] As described above, if the protrusion 1121 reduces the uniformity of the upper surface of the interlayer insulating layer 12, this will increase the non-uniformity of the film thickness of the functional layer, resulting in a decrease in light-emitting efficiency, a decrease in optical properties, and a shortened lifespan.

[0088] In contrast, in the self-emitting panel according to the embodiment, the region 13ap where the functional layer has a large thickness and its periphery are made non-luminous by the intra-pixel insulating layer 30, not above the protrusion 1121. Therefore, only the region 13aq where the functional layer has a uniform thickness above the protrusion 1121 is made luminous, so that current concentration does not occur in the functional layer, and the deterioration of the functional layer can be prevented from progressing non-uniformly, thereby making it possible to extend the life of the element. In addition, in designing the light-emitting element, it is sufficient to optimize the thickness of each functional layer in the region 13aq, which makes it easy to improve the light-emitting efficiency and the light extraction efficiency. Furthermore, when the light-emitting element has a resonator structure, it is sufficient to design the resonator structure taking into consideration only the thickness of the functional layer in the region 13aq, and it is possible to prevent color shifts and the like caused by light emitted from the region 13ap with different optical lengths.

[0089] <Self-emission panel manufacturing method> Hereinafter, a method for manufacturing an organic EL panel as a method for manufacturing a self-emission panel according to one embodiment of the present disclosure will be described with reference to the drawings. Figures 9(a) to 12(b) are schematic cross-sectional views showing the states in each step in the manufacture of an organic EL panel.

[0090] In an organic EL panel, the pixel electrode (lower electrode) functions as an anode of the organic EL element, and the counter electrode (upper electrode, common electrode) functions as a cathode of the organic EL element.

[0091] (1) Formation of Substrate 11 and Interlayer Insulating Layer 12 First, the TFT layer 112 is formed on the base material 111 to form the substrate 11 (step S10). The TFT layer 112 can be formed by a known method for manufacturing a TFT.

[0092] 9(a), an interlayer insulating layer 12 is formed on the substrate 11 (step S20). The interlayer insulating layer 12 can be formed by laminating layers using, for example, a plasma CVD method, a sputtering method, or the like.

[0093] Next, a contact hole is formed by dry etching at a location on the source electrode of the TFT layer in the interlayer insulating layer 12. The contact hole is formed so that the surface of the source electrode is exposed at the bottom thereof.

[0094] Next, a connection electrode layer is formed along the inner wall of the contact hole. A part of the upper part of the connection electrode layer is disposed on the interlayer insulating layer 12. The connection electrode layer can be formed by, for example, a sputtering method, and after forming a metal film, it is patterned by using a photolithography method and a wet etching method.

[0095] (2) Formation of pixel electrode 13 9(b), a pixel electrode material layer 130 is formed on the interlayer insulating layer 12 (step S31). The pixel electrode material layer 130 can be formed by using, for example, a vacuum deposition method, a sputtering method, or the like. 9(c), the pixel electrode material layer 130 is patterned by etching to form a plurality of pixel electrodes 13 partitioned into sub-pixels (step S32). The pixel electrodes 13 function as anodes of the respective organic EL elements.

[0096] The method for forming the pixel electrode 13 is not limited to the above-mentioned method. For example, the pixel electrode 13 and the hole injection layer 15 may be formed together by forming the hole injection material layer 150 on the pixel electrode material layer 130 and patterning the pixel electrode material layer 130 and the hole injection material layer 150 by etching.

[0097] (3) Formation of the Intra-Pixel Insulating Layer 30 Next, as shown in FIG. 9(d), a resin for an insulating layer, which is a material for the intra-pixel insulating layer 30, is applied onto the pixel electrode 13 and the interlayer insulating layer 12 to form an intra-pixel insulating material layer 300. The intra-pixel insulating material layer 300 is formed by uniformly applying a solution in which an acrylic resin, which is a resin for an insulating layer, is dissolved in a solvent onto the pixel electrode 13 and the interlayer insulating layer 12 by using a spin coating method or the like (step S41). Then, the intra-pixel insulating material layer 300 is subjected to pattern exposure and development to form the intra-pixel insulating layer 30 (FIG. 7(d), step S42), and the intra-pixel insulating layer 30 is baked. For example, the photomask used for patterning the top layer of the TFT layer 112 corresponding to the protrusion 1121 can be used as a photomask for pattern exposure. Note that depending on the patterning method for the top layer of the TFT layer 112 and whether the resin for the insulating layer is negative or positive, negative-positive inversion of the photomask may be required. Also, when the resin for the insulating layer is a negative photoresist, the opening of the photomask may be enlarged, or when the resin for the insulating layer is a positive photoresist, the opening of the photomask may be reduced. In this way, the intra-pixel insulating layer 30 can be formed to cover the area other than above the protrusion 1121 and its vicinity. The intra-pixel insulating layer is baked, for example, at a temperature of 150° C. to 210° C. for 60 minutes.

[0098] Note that when forming the intra-pixel insulating layer 30, the intra-pixel insulating layer 30 and the pixel regulating layer 141 may be integrally molded using the same resin material. Alternatively, for example, before or after the formation of the intra-pixel insulating layer 30, the pixel regulating layer 141 may be formed by the same manufacturing process.

[0099] (4) Formation of partition wall 14 Next, as shown in FIG. 10(a), a partition resin, which is a material for the partition 14, is applied onto the pixel electrode 13, the pixel insulating layer 30, and the interlayer insulating layer 12 to form a partition material layer 140. The partition material layer 140 is formed by uniformly applying a solution of a phenol resin, which is a partition layer resin, dissolved in a solvent (e.g., a mixed solvent of ethyl lactate and GBL) onto the pixel electrode 13, the pixel insulating layer 30, and the interlayer insulating layer 12 by a spin coating method or the like (step S51). Then, the partition material layer 140 is subjected to pattern exposure and development to form the partition 14 as shown in FIG. 10(b) (step S52), and the partition 14 is baked. As a result, an opening 14a, which is a region for forming the light-emitting layer 17, is defined. The partition 14 is baked, for example, at a temperature of 150° C. or higher and 210° C. or lower for 60 minutes.

[0100] In the process of forming the partition wall 14, the surface of the partition wall 14 may be further subjected to surface treatment with a predetermined alkaline solution, water, an organic solvent, or the like, or may be subjected to plasma treatment. This is performed for the purpose of adjusting the contact angle of the partition wall 14 with respect to the ink (solution) applied to the openings 14a, or for the purpose of imparting water repellency to the surface.

[0101] (5) Formation of hole injection layer 15 Next, as shown in FIG. 10(c), ink containing a constituent material of the hole injection layer 15 is ejected from the nozzle of the inkjet head 401 into the opening 14a defined by the partition 14 to apply it onto the pixel electrode 13 in the opening 14a, and then baked (dried) to form the hole injection layer 15 (step S60).

[0102] (6) Formation of hole transport layer 16 Next, as shown in FIG. 10(d), ink containing a constituent material of the hole transport layer 16 is ejected from the nozzle of the inkjet head 402 into the opening 14a defined by the partition 14 to apply it onto the hole injection layer 15 in the opening 14a, and then baked (dried) to form the hole transport layer 16 (step S70).

[0103] (7) Formation of light-emitting layer 17 Next, as shown in FIG. 11(a), ink containing the constituent material of the light-emitting layer 17 is ejected from the nozzle of the inkjet head 403 and applied onto the hole transport layer 16 in the opening 14a, and then baked (dried) to form the light-emitting layer 17 (step S80).

[0104] (8) Formation of electron transport layer 18 11(b), the electron transport layer 18 is formed on the light emitting layer 17 and the partition wall 14 (step S90). The electron transport layer 18 is formed, for example, by forming a film of an organic compound, which is the material of the electron transport layer 18, in common to each subpixel by a vapor deposition method.

[0105] (9) Formation of electron injection layer 19 11(c), the electron injection layer 19 is formed on the electron transport layer 18 (step S100). The electron injection layer 19 is formed by, for example, depositing an organic material with electron transport properties and a doped metal or a compound thereof in common to each subpixel by a co-evaporation method.

[0106] (10) Formation of Counter Electrode 20 12(a), a counter electrode 20 is formed on the electron injection layer 19 (step S110). The counter electrode 20 is formed by depositing ITO, IZO, silver, aluminum, or the like by a sputtering method or a vacuum deposition method. The counter electrode 20 functions as a cathode for each organic EL element.

[0107] (11) Formation of sealing layer 21 12(b), the sealing layer 21 is formed on the counter electrode 20 (step S120). The sealing layer 21 can be formed by depositing SiON, SiN, or the like by a sputtering method, a CVD method, or the like. Note that a sealing resin layer may be further formed on the inorganic film such as SiON or SiN by coating and baking.

[0108] A color filter and an upper substrate may be placed on and bonded to the sealing layer 21 .

[0109] Second Embodiment In the first embodiment, a case has been described in which the intra-pixel insulating layer 30 is used to make the first region 13ap not on the protrusion 1121 and its periphery a non-light-emitting region in the light-emitting element, and only the second region 13aq on the protrusion 1121 a light-emitting region, thereby making the film thickness uniform within the light-emitting region. However, although the first region 13ap not on the protrusion 1121 and the second region 13aq on the protrusion 1121 have different functional layer film thicknesses, the film thickness of the functional layer is uniform within each region, so either may be used as the light-emitting region.

[0110] In the second embodiment, a case will be described in which the intra-pixel insulating layer 30 defines the second region 13aq on the protrusion 1121 and its periphery as a non-light-emitting region in the light-emitting element, and defines only the first region 13ap not on the protrusion 1121 as a light-emitting region. Note that the organic EL panel according to the second embodiment differs from the organic EL panel according to the first embodiment only in the position of the intra-pixel insulating layer 30, and therefore only the position of the intra-pixel insulating layer 30 will be described and other configurations will be omitted.

[0111] (1) Structure of organic EL element 2A Fig. 14 is a schematic cross-sectional view of a portion of the organic EL panel 10A, corresponding to the cross section taken along line AA in Fig. 3. Each of the sub-pixels 100R, 100G, and 100B of the organic EL panel 10A is composed of organic EL elements 2A(R), 2A(G), and 2A(B), which are self-luminous elements. Hereinafter, when there is no need to distinguish between the organic EL elements 2A(R), 2A(G), and 2A(B), they will be described as organic EL element 2A.

[0112] <Components of organic EL elements> (1) Intra-pixel insulation layer The intra-pixel insulating layer 30 is interposed between the pixel electrode 13 and the hole injection layer 15 above and in the vicinity of the protrusion 1121, and serves to make the area where the intra-pixel insulating layer 30 exists a non-light-emitting area in plan view.

[0113] FIG. 15 is a schematic plan view showing the relationship between the pixel insulating layer 30, the pixel electrode 13, the protruding portion 1121, the partition wall 14, and the pixel restricting layer 141. As shown in FIG. 15(a), a part of the periphery of the pixel electrode 13 is covered by the partition wall 14 and the pixel restricting layer 141, and the opening 13a is exposed. As shown in FIG. 15(b), the pixel insulating layer 30 is formed so as to cover the entire second region 13aq on the protruding portion 1121 of the opening 13a and the region of the first region 13ap not on the protruding portion 1121 that is in contact with the second region 13aq. As shown in FIG. 14, on the upper surface of the interlayer insulating layer 12, the second region 13aq on the protruding portion 1121 and its periphery have a shape convex upward from the first region 13ap not on the protruding portion 1121. The pixel insulating layer 30 has the function of making the film thickness uniform within the effective range by making only the first region 13ap that is not on the protrusion 1121 the effective range of the functional layer, by making the second region 13aq and its surrounding area a non-light-emitting region within the light-emitting element.

[0114] The upper surface of the intra-pixel insulating layer 30 is lower than the upper surface of the partition wall 14 and is preferably at the same height as the upper surface of the pixel regulating layer 141 or lower than the upper surface of the pixel regulating layer 141 .

[0115] The material of the pixel insulating layer 30 has insulating properties. The material of the pixel insulating layer 30 may have lyophilicity with respect to the ink for forming the functional layer. The pixel insulating layer 30 is made of, for example, an insulating organic material, such as an acrylic resin, a polyimide resin, a siloxane resin, or a phenol resin.

[0116] The intra-pixel insulating layer 30 and the pixel regulating layer 141 may be made of the same material, and may be formed at the same time.

[0117] <Self-emission panel manufacturing method> Hereinafter, a method for manufacturing an organic EL panel as a method for manufacturing a self-emitting panel according to one embodiment of the present disclosure will be described with reference to the drawings. Note that the method for manufacturing a self-emitting panel according to embodiment 2 is characterized only in the method for manufacturing the intra-pixel insulating layer 30, and is otherwise similar to the method for manufacturing a self-emitting panel according to embodiment 1. Therefore, only the method for manufacturing the intra-pixel insulating layer 30 will be described, and other descriptions will be omitted.

[0118] (1) Formation of the intra-pixel insulating layer 30 After performing steps S10 to S32 in the first embodiment to form the pixel electrode 13 as shown in Fig. 9(c), as shown in Fig. 15(a), an insulating layer resin, which is a material for the intra-pixel insulating layer 30, is applied onto the pixel electrode 13 and the interlayer insulating layer 12 to form an intra-pixel insulating material layer 300. The intra-pixel insulating material layer 300 is formed by uniformly applying a solution in which an acrylic resin, which is the insulating layer resin, is dissolved in a solvent onto the pixel electrode 13 and the interlayer insulating layer 12 by using a spin coating method or the like. Then, the intra-pixel insulating material layer 300 is subjected to pattern exposure and development to form the intra-pixel insulating layer 30 (FIG. 15(b)), and the intra-pixel insulating layer 30 is baked. As a photomask for pattern exposure, for example, the photomask used for patterning the top layer of the TFT layer 112 corresponding to the protrusion 1121 can be used. Note that depending on the patterning method for the top layer of the TFT layer 112 and whether the insulating layer resin is a negative type or a positive type, negative-positive inversion of the photomask may be required. If the insulating layer resin is a negative type photoresist, the opening of the photomask may be enlarged, or if the insulating layer resin is a positive type photoresist, the opening of the photomask may be reduced. In this way, the intra-pixel insulating layer 30 that covers the entire area of ​​the protrusion 1121 and its vicinity can be formed. The intra-pixel insulating layer is baked, for example, at a temperature of 150° C. to 210° C. for 60 minutes.

[0119] The following steps are the same as steps S51 to S120 according to the first embodiment, and therefore the description thereof will be omitted.

[0120] <Summary> In the self-emitting panel according to the second embodiment, the region 13aq where the functional layer has a small thickness and its periphery are made into a non-emitting region by the pixel insulating layer 30. Therefore, since only the region 13ap where the functional layer has a uniform thickness is made into a emitting region, current concentration does not occur in the functional layer, and the deterioration of the functional layer is prevented from progressing non-uniformly, and the element can be made to have a long life. In addition, in designing the light-emitting element, it is sufficient to optimize the thickness of each functional layer in the region 13ap, which makes it easy to improve the light-emitting efficiency and the light extraction efficiency. Furthermore, when the light-emitting element has a resonator structure, it is sufficient to design the resonator structure taking into consideration only the thickness of the functional layer in the region 13ap, and it is possible to prevent color shifts and the like caused by light emitted from the region 13aq with different optical lengths.

[0121] <<Variations>> Although an organic EL panel as a self-emitting panel and a manufacturing method for an organic EL panel have been described above as one embodiment of the present disclosure, the present invention is not limited to the above description except for its essential characteristic components. Below, a modified example that is another embodiment of the present invention will be described.

[0122] (1) In the above first and second embodiments, the pixel electrode is an anode, the counter electrode is a cathode, and the organic EL element is a top emission type. However, for example, the pixel electrode may be a cathode, and the counter electrode may be an anode. Also, for example, the organic EL element may be a bottom emission type. In this case, the pixel electrode is formed of a light-transmitting conductive material, and the counter electrode is formed of a light-reflective conductive material. Also, at least a portion of the substrate 11 that is to be a layer below the pixel electrode is light-transmitting.

[0123] The self-luminous element is not limited to an organic EL element, but may be another element such as a QLED.

[0124] (2) In the above first and second embodiments, the hole injection layer 15, the hole transport layer 16, and the light emitting layer 17 are all formed by a coating process. However, the light emitting element only needs to include at least one coating film, and the other layers may be formed by a deposition method, a sputtering method, or the like. In this case, the pixel insulating layer only needs to be located above the pixel electrode and below the coating film, and does not need to be located directly above the pixel electrode. Alternatively, for example, one or more of the electron transport layer 18 and the electron injection layer 19 may be formed by a coating process.

[0125] (3) In the above first and second embodiments, the intra-pixel insulating layer 30 is formed of the same material as the pixel regulating layer 141, but it is sufficient that the intra-pixel insulating layer 30 is formed of a material having insulating properties, and may be formed of, for example, the same material as the partition wall 14. For example, in the case of a so-called pixel bank in which each light-emitting element is partitioned by a partition wall, by forming the intra-pixel insulating layer 30 and the partition wall 14 of the same material, the intra-pixel insulating layer 30 and the partition wall 14 can be formed simultaneously.

[0126] (4) In the above first and second embodiments, the organic EL element 2 has a configuration including the electron transport layer 18, the electron injection layer 19, the hole injection layer 15, and the hole transport layer 16, but is not limited thereto. For example, the organic EL element may not have the electron transport layer 18, or the hole transport layer 16. Also, for example, instead of the hole injection layer 15 and the hole transport layer 16, a single hole injection transport layer may be provided. Also, for example, an intermediate layer made of any one of an alkali metal, an alkaline earth metal, and a rare earth, or a fluoride thereof, may be provided between the light-emitting layer 17 and the electron transport layer 18.

[0127] Furthermore, the emission colors of the light-emitting layer 17 are not limited to two colors or three colors of red, green, and blue, but may be four or more colors including yellow and purple, and the combinations of the three colors are not limited to those mentioned above.

[0128] (5) In the above embodiment, the ink is a solution containing a functional material as a solute. However, the present invention is not limited to this and may be a colloidal solution or suspension in which a functional material is dispersed in a mixed solvent.

[0129] (6) As long as it is possible to apply ink with high precision through a nozzle, the apparatus is not limited to the inkjet apparatus in the above embodiment, and a dispenser type application apparatus that continuously ejects ink onto a substrate may be used.

[0130] (7) In the above embodiment, the self-emitting panel is a display panel; however, the use of the self-emitting panel is not limited to this. For example, the self-emitting panel may be a lighting panel or a panel for a functional device that is optically transparent when not in operation. [Industrial Applicability]

[0131] The present invention is ideal as a method for achieving uniform film thickness and improving luminous efficiency, light extraction efficiency, and life span in a self-emission panel equipped with light-emitting elements in which functional layers are formed by a wet process. [Explanation of symbols]

[0132] 1 Display device 10, 10A Self-luminous panel (organic EL panel) 2. 2A Light-emitting element (organic EL element) 11 Substrate 111 Base material 112 TFT layers 1121 Protrusion 12 Interlayer insulation layer 13 Pixel electrode 13a opening 13ap area 13aq area 30 Intra-pixel insulation layer 14 Bulkhead 141 Pixel Control Layer 15 Hole injection layer 16 Hole transport layer 17 Emitting layer 18 Electron transport layer 19 Electron injection layer 20 Counter electrode 21 Sealing layer

Claims

1. A substrate; A drive circuit layer disposed on the substrate; an interlayer insulating layer disposed on the drive circuit layer; a light emitting element layer including a plurality of light emitting elements disposed on the interlayer insulating layer; Equipped with the drive circuit layer includes wiring and a semiconductor circuit corresponding to a light emitting element, and has a protruding portion protruding toward the interlayer insulating layer; the light-emitting element layer includes a plurality of pixel electrodes formed for each of the light-emitting elements, a functional layer made of a coating film disposed above each of the plurality of pixel electrodes, a counter electrode disposed above the functional layer, and an intra-pixel insulating layer disposed between at least a portion of the pixel electrodes and the counter electrode; a region above the protruding portion on the upper surface of the interlayer insulating layer is convex upward relative to a region not above the protruding portion, When the light-emitting element including the intra-pixel insulating layer is viewed in plan, the light-emitting element includes at least a part of an area above the protrusion as a light-emitting area, and an area where the intra-pixel insulating layer is present as a non-light-emitting area includes the entire area not above the protrusion. Self-luminous panel.

2. A substrate; A drive circuit layer disposed on the substrate; an interlayer insulating layer disposed on the drive circuit layer; a light emitting element layer including a plurality of light emitting elements disposed on the interlayer insulating layer; Equipped with the drive circuit layer includes wiring and a semiconductor circuit corresponding to a light emitting element, and has a protruding portion protruding toward the interlayer insulating layer; the light-emitting element layer includes a plurality of pixel electrodes formed for each of the light-emitting elements, a functional layer made of a coating film disposed above each of the plurality of pixel electrodes, a counter electrode disposed above the functional layer, and an intra-pixel insulating layer disposed between at least a portion of the pixel electrodes and the counter electrode; a region above the protruding portion on the upper surface of the interlayer insulating layer is convex upward relative to a region not above the protruding portion, When the light-emitting element including the intra-pixel insulating layer is viewed in plan, the light-emitting element includes at least a part of the region that is not above the protrusion as a light-emitting region, and the region where the intra-pixel insulating layer is present, which is a non-light-emitting region, includes the entire region above the protrusion. Self-luminous panel.

3. The drive circuit layer is composed of a plurality of layers, and the protrusion is a layer of the drive circuit layer on the opposing electrode side. The self-emission panel according to claim 1 .

4. A coating film made of the same material as the functional layer is provided between the pixel insulating layer and the counter electrode. The self-emission panel according to claim 1 .

5. a plurality of elongated partition walls disposed on the interlayer insulating layer and arranged in parallel between the pixel electrodes; The functional layer is disposed in a gap between a pair of adjacent partition walls. The self-emission panel according to claim 1 .

6. A substrate; A drive circuit layer disposed on the substrate; an interlayer insulating layer disposed on the drive circuit layer; a light emitting element layer including a plurality of light emitting elements disposed on the interlayer insulating layer; Equipped with the drive circuit layer includes wiring and a semiconductor circuit corresponding to a light emitting element, and has a protruding portion protruding toward the interlayer insulating layer; the light-emitting element layer includes a plurality of pixel electrodes formed for each of the light-emitting elements, a functional layer made of a coating film disposed above each of the plurality of pixel electrodes, a counter electrode disposed above the functional layer, and an intra-pixel insulating layer disposed between at least a portion of the pixel electrodes and the counter electrode; When a light-emitting element including the intra-pixel insulating layer is viewed in plan, the light-emitting element includes at least a part of a region above the protrusion as a light-emitting region, and a region of the intra-pixel insulating layer that is a non-light-emitting region includes the entire region not above the protrusion, a plurality of elongated partition walls disposed on the interlayer insulating layer and arranged in parallel between the pixel electrodes; the functional layer is disposed in a gap between a pair of adjacent partition walls, The pixel insulating layer and the partition wall are formed from the same material. Self-luminous panel.

7. A substrate; A drive circuit layer disposed on the substrate; an interlayer insulating layer disposed on the drive circuit layer; a light emitting element layer including a plurality of light emitting elements disposed on the interlayer insulating layer; Equipped with the drive circuit layer includes wiring and a semiconductor circuit corresponding to a light emitting element, and has a protruding portion protruding toward the interlayer insulating layer; the light-emitting element layer includes a plurality of pixel electrodes formed for each of the light-emitting elements, a functional layer made of a coating film disposed above each of the plurality of pixel electrodes, a counter electrode disposed above the functional layer, and an intra-pixel insulating layer disposed between at least a portion of the pixel electrodes and the counter electrode; When a light-emitting element including the intra-pixel insulating layer is viewed in plan, the light-emitting element includes at least a part of a region that is not above the protrusion as a light-emitting region, and a region in which the intra-pixel insulating layer is present, which is a non-light-emitting region, includes the entire region above the protrusion, a plurality of elongated partition walls disposed on the interlayer insulating layer and arranged in parallel between the pixel electrodes; the functional layer is disposed in a gap between a pair of adjacent partition walls, The pixel insulating layer and the partition wall are formed from the same material. Self-luminous panel.

8. The liquid repellency of the material of the intra-pixel insulating layer to the ink material of the functional layer is lower than the liquid repellency of the material of the partition wall to the ink material of the functional layer. The self-emitting panel according to claim 5 .

9. a pixel regulation layer disposed on the interlayer insulating layer and juxtaposed between the pixel electrodes in a gap between a pair of adjacent partition walls; The pixel insulating layer and the pixel regulation layer are formed from the same material. The self-emitting panel according to claim 5 .

10. forming a driving circuit layer on the substrate; forming an insulating layer on the driving circuit layer; forming a plurality of pixel electrodes; forming an intra-pixel insulating layer in a first region above the pixel electrode; forming a functional layer by coating above the pixel electrode including above the pixel insulating layer; forming a counter electrode above the functional layer; the drive circuit layer includes wiring and a semiconductor circuit corresponding to a light-emitting element, and has a protruding portion protruding toward the insulating layer; a region above the protrusion on the upper surface of the insulating layer is convex upward relative to a region not above the protrusion, The first region is the entire region above the pixel electrode but not above the protrusion. A method for manufacturing a self-emitting panel.

11. forming a driving circuit layer on the substrate; forming an insulating layer on the driving circuit layer; forming a plurality of pixel electrodes; forming an intra-pixel insulating layer in a second region above the pixel electrode; forming a functional layer by coating above the pixel electrode including above the pixel insulating layer; forming a counter electrode above the functional layer; the drive circuit layer includes wiring and a semiconductor circuit corresponding to a light-emitting element, and has a protruding portion protruding toward the insulating layer; a region above the protrusion on the upper surface of the insulating layer is convex upward relative to a region not above the protrusion, The second region is the entire region above the pixel electrode and above the protrusion. A method for manufacturing a self-emitting panel.

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