Indication device

Abstract

The present invention provides a display device that can prevent color mixing and improve luminous efficiency. [Solution] The display device has a plurality of pixels and a plurality of apertures provided in the plurality of pixels, A display device comprising: a plurality of banks surrounding the plurality of openings; and an organic EL layer provided in each of the plurality of openings, wherein each of the plurality of banks has at least one first region and at least one second region, the first region having a cross-sectional shape of a first convex portion having a first end and a second end, the second region having a cross-sectional shape of a second convex portion having a third end and a fourth end, the first end and the second end being forward tapered, the third end being forward tapered, and the fourth end being inverse tapered.

Description

Technical Field

[0001] Embodiments of the present invention relate to a display device.

Background Art

[0002] A display device having an organic EL (Electro-Luminescence) layer has been developed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] This embodiment provides a display device that can prevent color mixing and improve luminous efficiency.

Means for Solving the Problems

[0005] A display device according to an embodiment includes: a plurality of pixels; a plurality of openings provided in the plurality of pixels; a plurality of banks surrounding the plurality of openings; an organic EL layer provided in each of the plurality of openings; and each of the plurality of banks has at least one first region and at least one second region, the first region has a cross-sectional shape of a first convex portion having a first end portion and a second end portion, the second region has a cross-sectional shape of a second convex portion having a third end portion and a fourth end portion, the first end portion and the second end portion have a tapered shape in sequence, The third end has a forward taper shape, The fourth end has an inverse tapered shape. [Brief explanation of the drawing]

[0006] [Figure 1] Figure 1 is an overall perspective view of the display device according to Embodiment 1. [Figure 2] Figure 2 is a partial plan view showing an example of a schematic configuration of a display device. [Figure 3] Figure 3 is a cross-sectional view showing the schematic cross-sectional structure of the display device along the line A1-A2 shown in Figure 2. [Figure 4] Figure 4 is a plan view showing an example of a schematic configuration of a display device. [Figure 5] Figure 5 is a cross-sectional view showing a schematic configuration of the display device along the line B1-B2 in Figure 4. [Figure 6] Figure 6 is a cross-sectional view showing a schematic configuration of the display device along the line C1-C2 in Figure 4. [Figure 7] Figure 7 is a cross-sectional view showing the manufacturing process of a display device. [Figure 8] Figure 8 is a cross-sectional view showing the manufacturing process of a display device. [Figure 9] Figure 9 is a cross-sectional view showing the manufacturing process of a display device. [Figure 10] Figure 10 is a cross-sectional view showing the manufacturing process of a display device. [Figure 11] Figure 11 is a cross-sectional view showing the manufacturing process of a display device. [Figure 12] Figure 12 is a cross-sectional view showing the manufacturing process of a display device. [Figure 13] Figure 13 is a cross-sectional view showing the manufacturing process of a display device. [Figure 14] Figure 14 is a cross-sectional view showing the manufacturing process of a display device. [Figure 15] Figure 15 is a cross-sectional view showing the manufacturing process of a display device. [Figure 16] Figure 16 is a cross-sectional view showing the manufacturing process of a display device. [Figure 17]FIG. 17 is a cross-sectional view showing a manufacturing process of a display device. [Figure 18] FIG. 18 is a cross-sectional view showing a manufacturing process of a display device. [Figure 19] FIG. 19 is a plan view showing an example of a schematic configuration of the display device according to Embodiment 1. [Figure 20] FIG. 20 is a cross-sectional view showing a schematic cross-sectional structure of the display device along line D1-D2 in FIG. 19. [Figure 21] FIG. 21 is a cross-sectional view showing a schematic cross-sectional structure of the display device along line E1-E2 in FIG. 19. [Figure 22] FIG. 22 is a cross-sectional view for explaining light emission in the display device shown in FIG. 5. [Figure 23] FIG. 23 is a cross-sectional view for explaining light emission in the display device shown in FIG. 6. [Figure 24] FIG. 24 is a partially enlarged view of FIG. 20. [Figure 25] FIG. 25 is a partially enlarged view of FIG. 21. [Figure 26] FIG. 26 is a plan view showing another configuration example of the display device in the embodiment. [Figure 27] FIG. 27 is a plan view showing another configuration example of the display device in the embodiment. [Figure 28] FIG. 28 is a plan view showing another configuration example of the display device in the embodiment. [Figure 29] FIG. 29 is a plan view showing another configuration example of the display device in the embodiment. [Figure 30] FIG. 30 is a plan view showing another configuration example of the display device in the embodiment. [Figure 31] FIG. 31 is a plan view showing another configuration example of the display device in the embodiment. [Figure 32] FIG. 32 is a plan view showing another configuration example of the display device in the embodiment.

MODE FOR CARRYING OUT THE INVENTION

[0007] The embodiments of the present invention will be described below with reference to the drawings. Note that the disclosure is merely an example, and modifications that can be easily conceived by those skilled in the art while maintaining the spirit of the invention are naturally included within the scope of the present invention. Furthermore, in order to clarify the explanation, the drawings may schematically represent the width, thickness, shape, etc., of each part compared to the actual embodiment, but these are merely examples and do not limit the interpretation of the present invention. In addition, in this specification and in each drawing, elements similar to those described above in previously shown drawings are denoted by the same reference numerals, and detailed explanations may be omitted as appropriate.

[0008] The embodiments described herein are not general in nature, but rather embodiments that illustrate the same or corresponding specific technical features of the present invention. A display device according to one embodiment will be described in detail below with reference to the drawings.

[0009] In this embodiment, the first direction X, the second direction Y, and the third direction Z are orthogonal to each other, but they may intersect at angles other than 90 degrees. The direction toward the tip of the arrow in the third direction Z is defined as up or upward, and the direction opposite to the direction toward the tip of the arrow in the third direction Z is defined as down or downward. The first direction X, the second direction Y, and the third direction Z may also be referred to as the X direction, the Y direction, and the Z direction, respectively.

[0010] Furthermore, when referring to "the second member above the first member" and "the second member below the first member," the second member may be in contact with the first member or may be located away from the first member. In the latter case, a third member may be interposed between the first member and the second member. On the other hand, when referring to "the second member above the first member" and "the second member below the first member," the second member is in contact with the first member.

[0011] Furthermore, assuming that there is an observation position for observing the display device on the tip side of the arrow in the third direction Z, viewing from this observation position toward the XY plane defined by the first direction X and the second direction Y is called a planar view. Viewing a cross-section of the display device in the XZ plane defined by the first direction X and the third direction Z, or in the YZ plane defined by the second direction Y and the third direction Z, is called a cross-sectional view.

[0012] [Embodiment 1] Figure 1 is an overall perspective view of the display device of Embodiment 1. The display device DSP has a display area DA and a peripheral area FA provided around the display area DA on a substrate SUB1. The display device DSP has a plurality of pixels PX arranged within the display area DA. In the display device DSP, light LT from the back surface is transmitted to the front surface, and vice versa.

[0013] The edge region EA of substrate SUB1 is located outside substrate SUB2. A wiring board PCS is provided in region EA. The wiring board PCS is equipped with a drive element DRV that outputs video signals and drive signals. Signals from the drive element DRV are input to the pixels PX of the display region DA via the wiring board PCS. Based on the video signal and various control signals, the pixels PX emit light.

[0014] Figure 2 is a partial plan view showing an example of the schematic configuration of a display device. Multiple pixels PX include pixels PXR that emit red light, pixels PXG that emit green light, and pixels PXB that emit blue light. Pixels PXR, PXG, and PXB are also referred to as the first pixel, second pixel, and third pixel, respectively.

[0015] Pixel PXR is positioned adjacent to pixel PXB along the first direction X. Pixel PXR is also positioned adjacent to pixel PXG along the second direction Y. Pixel PXG is positioned adjacent to pixel PXB along the first direction X. Pixel PXG is positioned adjacent to pixel PXR along the second direction Y. Pixel PXB is positioned adjacent to pixels PXR and PXG along the first direction. Pixel PXB is also positioned adjacent to other pixels PXB along the second direction Y.

[0016] Figure 3 is a cross-sectional view showing the schematic cross-sectional structure of the display device along the line A1-A2 shown in Figure 2. The base material BA1 may be made of glass or a resin material, for example. The resin material may be acrylic, polyimide, polyethylene terephthalate, polyethylene naphthalate, etc., and may be formed as a single layer or a laminate of multiple layers of any of these materials.

[0017] An insulating layer UC1 is provided on the substrate BA1. The insulating layer UC1 is formed, for example, by forming a single layer or a laminate of silicon oxide film and silicon nitride film.

[0018] A light-shielding layer BM may be provided on the insulating layer UC1, superimposed on the transistor Tr. The light-shielding layer BM suppresses changes in transistor characteristics caused by light penetration from the back surface of the transistor Tr's channel. If the light-shielding layer BM is formed of a conductive layer, it is also possible to impart a back-gate effect to the transistor Tr by applying a predetermined potential.

[0019] An insulating layer UC2 is provided, covering the insulating layer UC1 and the light-shielding layer BM. The insulating layer UC2 can be made of the same material as the insulating layer UC1. The insulating layer UC2 may be made of a different material than the insulating layer UC1. For example, silicon oxide can be used for the insulating layer UC1 and silicon nitride for the insulating layer UC2. The insulating layers UC1 and UC2 together constitute the insulating layer UC.

[0020] A transistor Tr is provided on the insulating layer UC. The transistor Tr has a semiconductor layer SC, an insulating layer GI, a gate electrode GE (scan line GL), an insulating layer ILI, a source electrode SE (signal line SL), and a drain electrode DE.

[0021] Amorphous silicon, polysilicon, or oxide semiconductor is used as the semiconductor layer SC. As the insulating layer GI, for example, silicon oxide or silicon nitride is provided as a single layer or in multiple layers.

[0022] For example, a molybdenum tungsten alloy (MoW) is used as the gate electrode (GE). The gate electrode (GE) may be integrally formed with the scan line (GL).

[0023] An insulating layer ILI is provided covering the semiconductor layer SC and the gate electrode GE. The insulating layer ILI is formed, for example, by a single layer or stacking of silicon oxide layers or silicon nitride layers.

[0024] A source electrode SE and a drain electrode DE are provided on the insulating layer ILI. The source electrode SE and the drain electrode DE are connected to the source region and drain region of the semiconductor layer SC, respectively, via contact holes provided in the insulating layer ILI and the insulating layer GI. The source electrode SE may be integrally formed with the signal line SL.

[0025] An insulating layer PAS is provided, covering the source electrode SE, the drain electrode DE, and the insulating layer ILI. An insulating layer PLL is provided, covering the insulating layer PAS.

[0026] The insulating layer PAS is formed using an inorganic insulating material. Examples of inorganic insulating materials include single-layer or multi-layer silicon oxide or silicon nitride. The insulating layer PLL is formed using an organic insulating material. Examples of organic insulating materials include photosensitive acrylic and polyimide. By providing the insulating layer PLL, the step created by the transistor Tr can be flattened.

[0027] In this embodiment, the structure from the substrate BA1 to the insulating layer PLL is a backplane BPS. Furthermore, the structure from the insulating layer UC1 to the insulating layer PLL is a backplane layer BPL.

[0028] Banks (also called protrusions or ribs) are provided on the insulating layer PLL. The same organic material as the insulating layer PLL is used for the banks. The region between adjacent banks is called an opening OP.

[0029] An opening provided in pixel PXR is denoted as opening OPR, an opening provided in pixel PXB as opening OPB, and an opening provided in pixel PXG as opening OPG. When there is no need to distinguish between openings OPR, OPB, and OPG, they are simply referred to as opening OP.

[0030] The edges of the opening OP preferably have a gently tapered shape in cross-section. If the edges of the opening OP have a steep shape, poor coverage will occur in the organic EL layer ELY that is formed later.

[0031] An anode AD is provided in the aperture OP. It can also be said that the anode AD is located between adjacent banks BK. The anode AD is connected to the drain electrode DE via contact holes provided in the insulating layer PAS and PLL. The anode provided in pixel PXR is denoted as anode ADR, the anode provided in pixel PXB as anode ADB, and the anode provided in pixel PXG as anode ADG. When there is no need to distinguish between anode ADR, anode ADG, and anode ADB, they are simply called anode AD.

[0032] The anode AD may be formed, for example, as a laminate of a reflective electrode and a transparent electrode. The reflective electrode is formed using a highly reflective conductive material, such as silver (Ag) or molybdenum tungsten alloy (MoW). The transparent electrode is formed using, for example, indium tin oxide (ITO) or indium zinc oxide (IZO).

[0033] An organic EL layer ELY is provided superimposed on the anode AD and between it and the adjacent bank BK. The organic EL layer ELY includes a hole injection layer, a hole transport layer, an emissive layer, an electron transport layer, and an electron injection layer. The organic EL layer ELY may further include an electron blocking layer and a hole blocking layer if necessary.

[0034] The organic EL layer provided in pixel PXR is denoted as organic EL layer ELYR, the organic EL layer provided in pixel PXB is denoted as organic EL layer ELYB, and the organic EL layer provided in pixel PXG is denoted as organic EL layer ELYG. When there is no need to distinguish between organic EL layers ELYR, ELYG, and ELYB, they are simply called organic EL layer ELY.

[0035] A cathode CD is provided on the organic EL layer ELY. The cathode CD is formed using, for example, a magnesium-silver alloy (MgAg) film, a single layer of silver (Ag), or a laminate of silver (Ag) and a transparent conductive material. The transparent conductive material can be, for example, indium tin oxide (ITO) or indium zinc oxide (IZO).

[0036] An insulating layer SEY1 is provided covering the cathode CD. The insulating layer SEY1 is formed of a light-transmitting inorganic insulating material layer or an organic insulating material layer. The insulating layer SEY1 is a layer for adjusting the optical cavity (also called a microcavity) of the light-emitting layer in the organic EL layer ELY.

[0037] An insulating layer SEY2 is provided covering the insulating layer SEY1. The insulating layer SEY1 has the function of preventing moisture from entering the organic EL layer ELY from the outside, sealing the organic EL layer ELY, and planarizing the layer. The insulating layer SEY2 may be formed, for example, by sandwiching an organic insulating material layer between two inorganic insulating material layers.

[0038] The inorganic insulating material layer of the insulating layer SEY2 is preferably an insulating layer with high gas barrier properties in order to prevent the intrusion of external moisture. An inorganic insulating material layer with high gas barrier properties is formed from, for example, an inorganic insulating layer material containing nitrogen, more specifically, silicon nitride or aluminum nitride.

[0039] The organic insulating material layer of the insulating layer SEY2 has the function of sealing the organic EL layer ELY and planarizing it. Examples of materials for the organic insulating layer include acrylic resin, epoxy resin, and polyimide resin.

[0040] An insulating layer OCI is provided on the insulating layer SEY2. The insulating layer OCI may be formed using, for example, epoxy resin or silicone resin. However, in the display device DSP shown in Figure 3, the insulating layer OCI does not need to be provided.

[0041] A circular polarizer CPP is provided on the insulating layer OCI, or on the insulating layer SEY2 if the insulating layer OCI is not provided. The circular polarizer CPP serves to prevent reflections from external light.

[0042] The light emitted in the organic EL layer ELY is extracted upwards via the cathode CD. In other words, the display device DSP of this embodiment has a top emission structure.

[0043] The configuration from the base material BA1 to the insulating layer SEY2 corresponds to substrate SUB1 shown in Figure 1. The circular polarizer CPP and insulating layer OCI correspond to substrate SUB2 shown in Figure 1.

[0044] Figure 4 is a plan view showing an example of a schematic configuration of a display device. Figure 4 shows the planar structure of a pixel unit PXU that includes a red-emitting pixel PXR, a green-emitting pixel PXG, and a blue-emitting pixel PXB. In Embodiment 1, pixels PX (pixels PXR, PXG, and PXB) are sometimes referred to as sub-pixels, and the pixel unit PXU that includes pixels PXR, PXG, and PXB is sometimes referred to as a pixel.

[0045] In the display device DSP shown in Figure 4, pixels PXR, PXG, and PXB each have banks BKR, BKG, and BKB, respectively. When banks BKR, BKG, and BKB are not distinguished, they are simply referred to as bank BK.

[0046] The bank BK of pixels PX (pixels PXR, PXG, and PXB) has regions BKS and BKJ. It can be said that at least one region BKS and at least one region BKJ surround the aperture OP.

[0047] Region BKJ comprises multiple regions, for example, region BKJ1, region BKJ2, region BKJ3, and region BKJ4. Region BKJ (regions BKJ1, BKJ2, BKJ3, and BKJ4) are arranged to extend from the inside to the outside of the opening OP. Note that the number of region BKJ is not limited to four; at least one is sufficient.

[0048] In other words, for example, one edge OPX1 along the first direction X of the opening OP is tangent to regions BKJ1 and BKS1. For example, one edge OPY1 along the second direction Y of the opening OP is tangent to regions BKJ2 and BKS2. For example, another edge OPX2 along the first direction X of the opening OP is tangent to regions BKJ3 and BKS3. For example, another edge OPY2 along the second direction Y of the opening OP is tangent to regions BKJ4 and BKS4.

[0049] Let vertex VTX1 be the intersection of edge OPX1 and edge OPY1. Let vertex VTX2 be the intersection of edge OPY1 and edge OPX2. Let vertex VTX3 be the intersection of edge OPX2 and edge OPY2. Let vertex VTX4 be the intersection of edge OPY2 and edge OPX1.

[0050] Region BKJ1 is adjacent to vertex VTX1. Region BKJ2 is adjacent to vertex VTX2. Region BKJ3 is adjacent to vertex VTX3. Region BKJ4 is adjacent to vertex VTX4.

[0051] The end of region BKJ opposite the opening OP, the so-called outer end, is designated as end EDJ. The end EDJs of regions BKJ1, BKJ2, BKJ3, and BKJ4 are designated as end EDJ1, end EDJ2, end EDJ3, and end EDJ4, respectively.

[0052] The end of region BKJ on the opening OP side, the so-called inner end, is designated as the end EDI. The end EDIs of regions BKJ1, BKJ2, BKJ3, and BKJ4 are not distinguished from the end EDJ and are simply referred to as end EDI.

[0053] Of the ends of region BKS, the end opposite the opening OP, the so-called outer end, is designated as end EDS. Of the ends of region BKS, the end on the opening OP side, the so-called inner end, is designated as end EDI, similar to region BKJ.

[0054] Figure 5 is a cross-sectional view showing a schematic configuration of the display device along line B1-B2 in Figure 4. Figure 6 is a cross-sectional view showing a schematic configuration of the display device along line C1-C2 in Figure 4. Figure 5 can also be considered a cross-sectional view of pixel PX including region BKJ. Figure 6 can also be considered a cross-sectional view of pixel PX including region BKS.

[0055] As shown in Figure 5, regions BKJ (regions BKJ1 and BKJ4) of the bank BK are provided on the backplane BPS. An opening OP is provided between regions BKJ1 and BKJ4. In reality, the adjacent regions BKJ1 and BKJ4 are integrally formed, surrounding the opening OP, as shown in Figure 4.

[0056] The cross-sectional shape of region BKJ1 is a convex shape, more specifically, a shape in which a second trapezoidal shape, whose upper side is even shorter than the lower side, is integrally formed on a first trapezoidal shape, whose upper side is even shorter than the lower side. The cross-sectional shapes of the other regions BKJ (regions BKJ2, BKJ3, and BKJ4) are similar.

[0057] Region BKJ1 has an end EDI on the opening OP side (inner side) and an end EDJ1 on the opposite side of the opening OP (outer side). Ends EDI and EDJ1 are formed in a so-called forward taper shape.

[0058] Region BKJ4 has an end EDI on the opening OP side (inner side) and an end EDJ4 on the opposite side of the opening OP (outer side). Ends EDI and EDJ4 are formed in a so-called forward taper shape.

[0059] An anode AD is provided in the opening OP. The anode AD superimposes a portion of region BKJ1 and a portion of region BKJ4.

[0060] The anode AD, region BKJ1, and region BKJ4 are covered by an organic EL layer ELY. The cathode CD is provided, covering the organic EL layer ELY.

[0061] As shown in Figure 6, a bank region BKS is provided on the backplane BPS. An opening OP is provided between two adjacent regions BKS. In reality, the two regions BKS are integrally formed, surrounding the opening OP, as shown in Figure 4.

[0062] Region BKS has an end EDI on the opening OP side (inner side) and an end EDS on the opposite side of the opening OP (outer side). End EDI is formed in a so-called forward taper shape. On the other hand, end EDS is formed in a so-called reverse taper shape.

[0063] The cross-sectional shape of region BKS is the same as that of region BKJ, but with one end replaced by an inverse taper. In other words, the cross-sectional shape of region BKS can be described as having a shape in which a second trapezoidal shape, with a shorter top edge than the bottom edge, is integrally formed on a first trapezoidal shape, with a shorter bottom edge than the top edge.

[0064] An anode AD is provided in the opening OP. The anode AD is superimposed on a portion of each of the two adjacent regions BKS.

[0065] An organic EL layer ELY is provided covering the anode AD and region BKS. A cathode CD is provided covering the organic EL layer ELY.

[0066] Near the edge EDS of region BKS, an organic EL laminate ELT is provided on the backplane BPS. The organic EL laminate ELT has the same material as the organic EL layer ELY and the same material as the cathode CD. That is, the organic EL laminate ELT includes a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer. If the organic EL layer ELY includes an electron blocking layer and a hole blocking layer, then the organic EL laminate ELT also includes an electron blocking layer and a hole blocking layer. The organic EL laminate ELT does not emit light because it is not in contact with the anode AD and no current flows through it.

[0067] As shown in Figure 6, the BKS region prevents the anode AD, organic EL layer ELY, and cathode CD from connecting to adjacent pixels PX. The anode AD, organic EL layer ELY, and cathode CD extend across adjacent pixels PX only in the portion of the pixel PX where the BKJ region is located (see Figure 5). Therefore, the majority of each of the anode AD, organic EL layer ELY, and cathode CD are not connected to adjacent pixels PX. This makes it possible to prevent color mixing.

[0068] Figures 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, and 18 are cross-sectional views showing the manufacturing process of a display device.

[0069] First, a backplane BPS is formed. On the backplane BPS, a material layer BKM is formed, consisting of the material of the bank BK (see Figure 7). As mentioned above, the material layer BKM can be formed from an organic material such as photosensitive acrylic or polyimide.

[0070] The material layer BKM is photoetched to form a bank BK (see Figure 8). Figure 8 shows two adjacent bank BKs. However, as shown in Figure 4, these two bank BKs are integrally formed surrounding the opening OP.

[0071] Of the ends of the bank BK, the end on the opening OP side, the so-called inner end, is designated as end EDI. The end on the opposite side of the opening OP, the so-called outer end, is designated as end EDO. Ends EDI and EDO are formed in a so-called forward taper shape.

[0072] The backplane BPS and bank BK are covered to form the anode AD (see Figure 9). The anode AD is covered to form the resist RES1 (see Figure 10). The resist RES1 can be formed using, for example, a photosensitive resin material.

[0073] A portion of the resist RES1 is removed, exposing a portion of the anode AD (see Figure 11). Post-bake (heating) of resist RES1 improves its adhesion.

[0074] A portion of the exposed anode AD is removed by etching (see Figure 12). The bank BK, anode AD, and resist RES1 are covered with resist RES2 (see Figure 13). The material of resist RES2 can be the same as that of resist RES1. The adhesion of resist RES2 is improved by post-baking (heating).

[0075] Remove resists RES1 and RES2 (see Figure 14). This exposes the anode AD and a portion of the bank BK not covered by the anode AD. The bank BK corresponds to region BKJ (regions BKJ1 and BKJ4) shown in Figure 5. The end EDOs correspond to end EDJ1 of region BKJ1 and end EDJ4 of region BKJ4.

[0076] The organic EL layer ELY is formed by covering the anode AD and region BKJ (regions BKJ1 and BKJ4) (see Figure 15). The organic EL layer ELY is formed by depositing the material that will become the organic EL layer. For example, three deposition sources ELS may be arranged so that the deposition direction changes, and deposition may be performed. This makes it possible to form the organic EL layer ELY with a uniform film thickness.

[0077] The cathode CD is formed by covering the organic EL layer ELY. This allows us to obtain the cross-sectional configuration of the pixel PX, including regions BKJ1 and BKJ4 (see Figure 5).

[0078] The manufacturing method for the cross-sectional structure of pixel PX including region BKS is described below. The manufacturing process shown up to Figure 13 is the same as the manufacturing method for region BKJ. After forming resist RES2 (see Figure 13), a portion of resist RES2 is removed (see Figure 16). This exposes a portion of bank BK. The adhesion of resist RES2 is improved by post-baking (heating).

[0079] Using resists RES1 and RES2 as masks, the exposed portion of bank BK is removed by etching. This etching removes the forward-tapered end EDO. By etching the exposed portion of bank BK, a so-called reverse-tapered end EDS is formed.

[0080] On the other hand, the edge EDI of bank BK is covered with the anode AD, organic EL layer ELY, cathode CD, resist RES1, and resist RES2, and is not etched. Therefore, the edge EDI remains in its forward tapered shape. Bank BK that has been partially etched corresponds to the region BKS shown in Figure 6.

[0081] Remove resists RES1 and RES2 (see Figure 17). This exposes the anode AD and region BKS.

[0082] The organic EL layer ELY is formed by covering the anode AD and region BKS (see Figure 18). The manufacturing process shown in Figure 18 is the same as the manufacturing process shown in Figure 15. Next, the cathode CD is formed by covering the organic EL layer ELY.

[0083] On the backplane, in the region where region BKS is not provided, an organic EL laminate ELT is provided, containing the same material as the organic EL layer ELY and the same material as the cathode CD. In other words, the organic EL laminate ELT is the residue of the organic EL layer ELY and the cathode CD. As a result, a cross-sectional configuration of a pixel PX including region BKS can be obtained (see Figure 6).

[0084] Figure 19 is a plan view showing an example of a schematic configuration of the display device of Embodiment 1. In Figure 19, in addition to the pixels PXR, PXG, and PXB shown in Figure 4, the touch sensor wiring TL arranged between these pixels is shown.

[0085] Figure 20 is a cross-sectional view showing the schematic cross-sectional structure of the display device along line D1-D2 in Figure 19. Figure 21 is a cross-sectional view showing the schematic cross-sectional structure of the display device along line E1-E2 in Figure 19. Figure 20 can also be considered a cross-sectional view of a pixel PX including region BKJ, similar to Figure 5. Figure 21 can also be considered a cross-sectional view of a pixel PX including region BKS, similar to Figure 6.

[0086] In Figure 20, similar to Figure 5, the cathode CD is formed from the backplane BPS. Insulating layers SEY1 and SEY2 are provided covering the cathode CD. An insulating layer OCI is provided on insulating layer SEY2. Touch sensor wiring TL is provided on insulating layer OCI between adjacent pixels PX. A circular polarizer CPP is provided on insulating layer OCI and wiring TL (see Figure 3).

[0087] In Figure 21, the cathode CD is formed from the backplane BPS, similar to Figure 6. An insulating layer SEY1 is provided covering the cathode CD. An insulating layer SEY2 is provided covering the insulating layer SEY1 and filling the region between the end EDS of region BKS.

[0088] An insulating layer OCI is provided on the insulating layer SEY2. Touch sensor wiring TL is provided on the insulating layer OCI between adjacent pixels PX. A circular polarizing plate CPP is provided on the insulating layer OCI and wiring TL.

[0089] Figure 22 is a cross-sectional view illustrating light emission in the display device shown in Figure 5. Figure 23 is a cross-sectional view illustrating light emission in the display device shown in Figure 6.

[0090] The region BKJ (bank BK) shown in Figure 22 has integrally formed protrusions BKJa and BKJb. Protrusion BKJa has ends EDJ and EDI. Protrusion BKJb is positioned on top of protrusion BKJa. Of the ends of protrusion BKJb, the end on the opening OP side is designated as end EGI. The upper surface of protrusion BKJb is designated as surface TFJ. Of the ends of protrusion BKJb, the end opposite to the opening OP is designated as end EGJ.

[0091] The cross-sectional shape of the convex part BKJa can be described as a trapezoid with the upper side shorter than the lower side. The cross-sectional shape of the convex part BKJb can also be described as a trapezoid with the upper side shorter than the lower side.

[0092] The anode AD, organic EL layer ELY, and cathode CD cover the end EGJ, surface TFJ, end EGI, and end EDI. Of the light emitted from the light-emitting layer of organic EL layer ELY, photon LTa is emitted directly upwards. Of the light emitted from the light-emitting layer of organic EL layer ELY, photon LTb is reflected by the end EDI and end EGI and emitted upwards.

[0093] The region BKS (bank BK) shown in Figure 23 has integrally formed protrusions BKSa and BKSb. Protrusion BKSa has end EDS and end EDI. Protrusion BKSb is positioned on protrusion BKSa. Of the ends of protrusion BKSb, the end on the opening OP side is designated as end EGI. The upper surface of protrusion BKSb is designated as surface TFS. Of the ends of protrusion BKSb, the end opposite to the opening OP is designated as end EGS.

[0094] The cross-sectional shape of the convex portion BKSa can be described as a trapezoid with a shorter lower side than the upper side. However, the cross-sectional shape of the convex portion BKSa is not limited to this. Depending on the angle of the inverse tapered end EDS, the cross-sectional shape of the convex portion BKSa may also be a trapezoid with a shorter upper side than the lower side. The cross-sectional shape of the convex portion BKSb can also be described as a trapezoid with a shorter upper side than the lower side.

[0095] The anode AD, organic EL layer ELY, and cathode CD cover the edge EGS, surface TFS, edge EGI, and edge EDI. Of the light emitted from the light-emitting layer of organic EL layer ELY, optical light LTc is emitted directly upwards. Of the light emitted from the light-emitting layer of organic EL layer ELY, optical light LTd is reflected by the edge EDI and edge EGI and emitted upwards.

[0096] As shown in Figures 22 and 23, the organic EL layer ELY is also formed on the end EDJ and end EGJ, as well as on the end EDS and end EGS. This expands the light-emitting area. As a result, a wide angle of luminescence efficiency can be obtained, improving the viewing angle brightness.

[0097] Anode AD and cathode CD are also formed on the end EDJ and end EGJ, as well as on the end EDS and end EGS. This allows for a larger electrode area, thereby suppressing the rise in drive voltage. As a result, power consumption can be reduced and frontal efficiency can be improved.

[0098] By adjusting the base angles of the convex parts BKJa and BKJb, as well as BKSa and BKSb, the luminous efficiency and chromaticity fluctuations over a wide angle can be made to match the luminous efficiency and chromaticity at the front. This makes it possible to improve the viewing angle characteristics.

[0099] In Figure 22, the convex portions BKJa and BKJb are each defined as equilateral trapezoidal shapes. The base angle of convex portion BKJa is defined as angle ADJ. The base angle of convex portion BKJb is defined as angle AGJ.

[0100] In Figure 23, the bottom angle of the convex BKSa on the opening OP side, i.e., the angle formed by the end EDI and the bottom surface of the convex BKSa, is defined as angle ADS. The convex BKSb is defined as an equilateral trapezoid. The bottom angle of the convex BKSb is defined as angle AGS.

[0101] The angles ADJ and ADS are preferably between 20° and 60°. The angles AGJ and AGS may be the same as those of angles ADJ and ADS, respectively.

[0102] As shown in Figure 23, the end EDS has an inverse tapered shape. Within the organic EL layer ELY, layers commonly formed across pixels PXR, PXG, and PXB, such as the hole injection layer, hole transport layer, and light-emitting layer, can be separated. This reduces charge leakage and suppresses color mixing.

[0103] Figure 24 is a magnified view of a portion of Figure 20. Figure 25 is a magnified view of a portion of Figure 21. The insulating layer SEY2 above the opening OP has irregularities corresponding to the opening OP, and as a whole it is recessed in an arc shape. Light emitted from the light-emitting layer in the organic EL layer ELY provided in the opening OP is focused by the recessed arc-shaped insulating layer SEY2. This improves the luminous efficiency at the front.

[0104] Furthermore, by adjusting the thickness of the insulating layers SEY2 and OCI, it is possible to adjust the height of the wiring TL (the distance along the third direction Z from the substrate BA1). By adjusting the height of the wiring TL, it is possible to improve chromaticity and viewing angle.

[0105] <Configuration Example 1> Figure 26 is a plan view showing another configuration example of the display device in the embodiment. In the configuration example shown in Figure 26, the position of region BKJ is different compared to the configuration example shown in Figure 4.

[0106] In the display device DSP shown in Figure 26, four regions BKJ are provided in one pixel PX. These four regions BKJ are located in the upper left and lower right corners of the aperture OP.

[0107] Within region BKS, the regions along the first direction X are designated as region BKS1 and region BKS3. Within region BKS, the regions along the second direction Y are designated as region BKS2 and region BKS4. Region BKS2 is located between region BKS1 and region BKS3. Region BKS4 is located between region BKS3 and region BKS1. The number of regions BKS is not limited to these. Within bank BK, all regions other than region BKJ correspond to region BKS.

[0108] Region BKJ1 is located adjacent to region BKS1. Region BKJ2 is located adjacent to region BKS2. Region BKJ3 is located adjacent to region BKS3. Region BKJ4 is located adjacent to region BKS4. Regions BKJ1, BKJ2, BKJ3, and BKJ4 are arranged to extend from the inside to the outside of the opening OP.

[0109] In other words, for example, one edge OPX1 along the first direction X of the opening OP is tangent to regions BKJ1 and BKS1. For example, one edge OPY1 along the second direction Y of the opening OP is tangent to regions BKJ2 and BKS2. For example, another edge OPX2 along the first direction X of the opening OP is tangent to regions BKJ3 and BKS3. For example, another edge OPY2 along the second direction Y of the opening OP is tangent to regions BKJ4 and BKS4.

[0110] Regions BKJ1 and BKJ2 are adjacent to vertex VTX1. Regions BKJ3 and BKJ4 are adjacent to vertex VTX3. However, Configuration Example 1 is not limited to this. Regions BKJ1 and BKJ4 may be adjacent to vertex VTX4, and regions BKJ2 and BKJ3 may be adjacent to vertex VTX2. Configuration Example 1 also achieves the same effects as Embodiment 1.

[0111] <Configuration Example 2> Figure 27 is a plan view showing another configuration example of the display device in the embodiment. In the configuration example shown in Figure 27, the position of region BKJ is different compared to the configuration example shown in Figure 4.

[0112] In the display device DSP shown in Figure 27, regions BKJ are provided at the center of the edge extending in the first direction X and the center of the edge extending in the second direction Y of the opening OP. In other words, for example, one edge OPX1 along the first direction X of the opening OP is in contact with regions BKS1, BKJ1, and BKS1. For example, one edge OPY1 along the second direction Y of the opening OP is in contact with regions BKS2, BKJ2, and BKS2. For example, another edge OPX2 along the first direction X of the opening OP is in contact with regions BKS3, BKJ3, and BKS3. For example, another edge OPY2 along the second direction Y of the opening OP is in contact with regions BKS4, BKJ4, and BKS4.

[0113] Region BKJ1 is located between vertices VTX1 and VTX4. Region BKJ2 is located between vertices VTX1 and VTX2. Region BKJ3 is located between vertices VTX2 and VTX3. Region BKJ4 is located between vertices VTX3 and VTX4. Configuration Example 2 also achieves the same effects as Embodiment 1.

[0114] <Configuration Example 3> Figure 28 is a plan view showing another configuration example of the display device in the embodiment. In the configuration example shown in Figure 28, the position of region BKJ is different compared to the configuration example shown in Figure 4.

[0115] In the display device DSP shown in Figure 28, two regions BKJ are provided adjacent to the edges of the opening OP that extend in the second direction Y. In other words, for example, one edge OPY1 along the second direction Y of the opening OP is adjacent to regions BKJ1, BKS2, and BKJ2. For example, another edge OPY2 along the second direction Y of the opening OP is adjacent to regions BKJ3, BKS4, and BKJ4. No regions BKJ are provided on edges OPX1 and OPX2 along the first direction X of the opening OP. Configuration Example 3 also achieves the same effects as Embodiment 1.

[0116] <Configuration Example 4> Figure 29 is a plan view showing another configuration example of the display device in the embodiment. In the configuration example shown in Figure 29, the position of region BKJ is different compared to the configuration example shown in Figure 4.

[0117] In the display device DSP shown in Figure 29, a region BKS is provided surrounding the opening OP. Regions BKJ extend from each of the four corners of region BKS. Regions BKS1, BKS2, BKS3, and BKS4 are the regions BKS adjacent to edges OPX1, OPY1, OPX2, and OPY2 of the opening OP, respectively. The intersection of region BKS1 and region BKS2 is designated as intersection INT1. The intersection of region BKS2 and region BKS3 is designated as intersection INT2. The intersection of region BKS3 and region BKS4 is designated as intersection INT3. The intersection of region BKS4 and region BKS1 is designated as intersection INT4.

[0118] For example, region BKJ1 extends from the intersection point INT1 of regions BKS1 and BKS2 in directions inclined in the first direction X and the second direction Y, respectively. For example, region BKJ2 extends from the intersection point INT2 of regions BKS2 and BKS3 in directions inclined in the first direction X and the second direction Y, respectively. For example, region BKJ3 extends from the intersection point INT3 of regions BKS2 and BKS3 in directions inclined in the first direction X and the second direction Y, respectively. For example, region BKJ4 extends from the intersection point INT4 of regions BKS4 and BKS1 in directions inclined in the first direction X and the second direction Y, respectively.

[0119] The intersection point INT1 of regions BKS1 and BKS2 is tangent to vertex VTX1. The intersection point INT2 of regions BKS2 and BKS3 is tangent to vertex VTX2. The intersection point INT3 of regions BKS3 and BKS4 is tangent to vertex VTX3. The intersection point INT4 of regions BKS4 and BKS1 is tangent to vertex VTX4.

[0120] Regions BKJ1 and BKJ3 extend in opposite directions. Regions BKJ2 and BKJ4 extend in opposite directions. Configuration Example 4 also achieves the same effects as Embodiment 1.

[0121] <Configuration Example 5> Figure 30 is a plan view showing another configuration example of the display device in the embodiment. In the configuration example shown in Figure 30, the position of region BKJ is different from that of the configuration example shown in Figure 4. Also, in the configuration example shown in Figure 30, two regions BKJ are provided not only along the side of the opening OP along the second direction Y, but also along the side along the first direction X.

[0122] In the display device DSP shown in Figure 30, two regions BKJ are provided adjacent to the edge of the opening OP extending in the first direction X and the edge extending in the second direction Y. In other words, for example, one edge OPX1 along the first direction X of the opening OP is adjacent to regions BKJ1, BKS1, and BKJ2. For example, one edge OPY1 along the second direction Y of the opening OP is adjacent to regions BKJ3, BKS2, and BKJ4. For example, another edge OPX2 along the first direction X of the opening OP is adjacent to regions BKJ5, BKS3, and BKJ6. For example, another edge OPY2 along the second direction Y of the opening OP is adjacent to regions BKJ7, BKS4, and BKJ8. Configuration Example 5 also achieves the same effects as Embodiment 1.

[0123] <Configuration Example 6> Figure 31 is a plan view showing another configuration example of the display device in the embodiment. In the configuration example shown in Figure 31, the position of region BKJ is different compared to the configuration example shown in Figure 4.

[0124] In the display device DSP shown in Figure 31, region BKS is provided adjacent to the edge of the opening OP extending in the first direction X. On the other hand, region BKJ is provided adjacent to the edge of the opening OP extending in the second direction Y.

[0125] In other words, for example, one edge OPX1 extending in the first direction X of the opening OP is tangent to region BKS1. For example, one edge OPY1 extending in the second direction Y of the opening OP is tangent to region BKJ1. For example, another edge OPX2 extending in the first direction X of the opening OP is tangent to region BKS2. For example, another edge OPY2 extending in the second direction Y of the opening OP is tangent to region BKJ2.

[0126] In example configuration 6, region BKJ is adjacent only to edges OPY1 and OPY2, but it is not limited to this. Region BKJ may be adjacent to edges OPX1 and OPX2, but not to edges OPY1 and OPY2. Configuration Example 6 also achieves the same effects as Embodiment 1.

[0127] <Configuration Example 7> Figure 32 is a plan view showing another configuration example of the display device in the embodiment. In the configuration example shown in Figure 32, the position of region BKJ is different from that of the configuration example shown in Figure 4. Also, the configuration example shown in Figure 32 differs from that shown in Figure 31 in that region BKJ is provided in contact with only one side along the second direction Y of the opening OP.

[0128] In the display device DSP shown in Figure 32, region BKS is provided adjacent to two sides of the opening OP extending in the first direction X and one of the sides extending in the second direction Y. On the other hand, region BKJ is provided adjacent to the other side of the opening OP extending in the second direction Y.

[0129] In other words, for example, one edge OPX1 extending in the first direction X of the opening OP is tangent to region BKS1. For example, one edge OPY1 extending in the second direction Y of the opening OP is tangent to region BKS2. For example, another edge OPX2 extending in the first direction X of the opening OP is tangent to region BKS3. For example, another edge OPY2 extending in the second direction Y of the opening OP is tangent to region BKJ1.

[0130] In example configuration 7, region BKJ is adjacent only to edge OPY2, but this is not limited to that. Region BKJ may be adjacent to any one of the other edges (edges OPX1, OPY1, or OPX2) and not adjacent to the other three edges. Configuration Example 7 also achieves the same effects as Embodiment 1.

[0131] In this disclosure, region BKJ and region BKS are referred to as the first region and the second region, respectively. The ends EDI and EDJ of region BKJ are referred to as the first end and the second end, respectively. The ends EDI and EDS of region BKS are referred to as the third end and the fourth end, respectively.

[0132] In this disclosure, the edges OPX1, OPY1, OPX2, and OPY2 of the opening OP are defined as the first edge, second edge, third edge, and fourth edge, respectively. The vertices VTX1, VTX2, VTX3, and VTX4 are defined as the first vertex, second vertex, third vertex, and fourth vertex, respectively. The intersections INT1, INT2, INT3, and INT4 are defined as the first intersection, second intersection, third intersection, and fourth intersection, respectively.

[0133] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of Symbols]

[0134] BK...bank, BKJ...region, BKJa...protrusion, BKJb...protrusion, BKS...region, BKSa...protrusion, BKSb...protrusion, DSP...display device, EDI...end, EDJ...end, EDS...end, ELT...organic EL laminate, ELY...organic EL layer, OCI...insulating layer, OP...aperture, PX...pixel, SEY1...insulating layer, SEY2...insulating layer.

Claims

1. Multiple pixels, Multiple openings are provided in the aforementioned multiple pixels, A plurality of banks surrounding the plurality of openings, Each of the aforementioned multiple openings is provided with an organic EL layer, Equipped with, Each of the aforementioned multiple banks has at least one first region and at least one second region, The first region has a cross-sectional shape of a first convex portion having a first end and a second end, The second region has a cross-sectional shape of the second protrusion, with a third end and a fourth end. The first end and the second end have a forward taper shape, The third end has a forward taper shape, The fourth end of the display device has an inverse tapered shape.

2. The opening has a first side and a third side along the first direction, and a second side and a fourth side along the second direction intersecting the first direction. The display device according to claim 1, wherein one first region and one second region are provided adjacent to the first, second, third, and fourth sides, respectively.

3. The intersection of the first and second sides is the first vertex, the intersection of the second and third sides is the second vertex, the intersection of the third and fourth sides is the third vertex, and the intersection of the fourth and first sides is the fourth vertex. The first region tangent to the first edge is adjacent to the first vertex, The first region adjacent to the second edge is adjacent to the second vertex, The first region adjacent to the third edge is adjacent to the third vertex, The display device according to claim 2, wherein the first region tangent to the fourth edge is adjacent to the fourth vertex.

4. The intersection of the first and second sides is the first vertex, the intersection of the second and third sides is the second vertex, the intersection of the third and fourth sides is the third vertex, and the intersection of the fourth and first sides is the fourth vertex. The first region tangent to the first edge is adjacent to the first vertex, The first region adjacent to the second edge is adjacent to the first vertex, The first region adjacent to the third edge is adjacent to the third vertex, The display device according to claim 2, wherein the first region tangent to the fourth edge is adjacent to the third vertex.

5. The intersection of the first and second sides is the first vertex, the intersection of the second and third sides is the second vertex, the intersection of the third and fourth sides is the third vertex, and the intersection of the fourth and first sides is the fourth vertex. The first region adjacent to the first edge is provided in the center of the first edge. The first region adjacent to the second side is provided in the center of the second side. The first region adjacent to the third side is located in the center of the third side. The display device according to claim 2, wherein the first region adjacent to the fourth side is provided in the center of the fourth side.

6. The opening has a first side and a third side along the first direction, and a second side and a fourth side along the second direction intersecting the first direction. Two first regions and one second region are provided adjacent to the second and fourth sides, respectively. The display device according to claim 1, wherein one second region is provided adjacent to the first side and the third side, respectively.

7. The opening has a first side and a third side along the first direction, and a second side and a fourth side along the second direction intersecting the first direction. The second region is provided, adjacent to the first, second, third, and fourth sides, and surrounding the opening. The intersection of the second region touching the first side and the second region touching the second side is the first intersection, the intersection of the second region touching the second side and the second region touching the third side is the second intersection, the intersection of the second region touching the third side and the second region touching the fourth side is the third intersection, and the intersection of the second region touching the fourth side and the second region touching the first side is the fourth intersection. The display device according to claim 1, wherein one first region extends from each of the first, second, third, and fourth intersections.

8. The opening has a first side and a third side along the first direction, and a second side and a fourth side along the second direction intersecting the first direction. The display device according to claim 1, wherein two first regions and one second region are provided adjacent to the first, second, third, and fourth sides, respectively.

9. The opening has a first side and a third side along the first direction, and a second side and a fourth side along the second direction intersecting the first direction. A first region is provided adjacent to each of the second and fourth sides, The display device according to claim 1, wherein one second region is provided adjacent to the first side and the third side, respectively.

10. The opening has a first side and a third side along the first direction, and a second side and a fourth side along the second direction intersecting the first direction. One of the aforementioned first regions is provided adjacent to the aforementioned fourth side, The display device according to claim 1, wherein one second region is provided adjacent to each of the first, second, and third sides.

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