Display device and method of manufacturing display device

Abstract

A display device with high resolution or a display device with high aperture ratio is provided, comprising: a first light-emitting element; and a second light-emitting element. First and second pixel electrodes, first and second light-emitting layers, and a common electrode are sequentially stacked in the first and second light-emitting elements, respectively. A first layer and a second layer are included in the region between the first and second light-emitting elements. The first layer overlaps with the second light-emitting layer and contains the same material as the first light-emitting layer. The second layer overlaps with the first light-emitting layer and contains the same material as the second light-emitting layer. In the region between the first and second light-emitting elements, the ends of the first light-emitting layers are opposite to the ends of the first layer, and the ends of the second light-emitting layers are opposite to the ends of the second layer.

Description

Technical Field

[0001] One embodiment of the present invention relates to a display device. Another embodiment of the present invention relates to a method for manufacturing a display device.

[0002] Note that one embodiment of the present invention is not limited to the above-described technical fields. Examples of technical fields within the scope of one embodiment of the present invention disclosed in this specification include semiconductor devices, display devices, light-emitting devices, energy storage devices, memory devices, electronic devices, lighting equipment, input devices, input / output devices, driving methods for the aforementioned devices, and manufacturing methods for the aforementioned devices. A semiconductor device refers to any device capable of operating by utilizing the characteristics of semiconductors. Prior Technology

[0003] In recent years, high-definition display panels have been in high demand. Devices requiring high-definition display panels include smartphones, tablets, and laptops. Additionally, fixed display devices such as televisions and monitors are also experiencing a demand for higher resolution. Furthermore, devices requiring the highest definition include those used in virtual reality (VR) or augmented reality (AR) applications.

[0004] In addition, typical examples of display devices that can be applied to display panels include liquid crystal display devices, light-emitting devices that have light-emitting elements such as organic EL (Electro Luminescence) elements or light-emitting diodes (LEDs), and electronic paper that displays by electrophoresis or the like.

[0005] For example, Patent Document 1 discloses an example of a display device for VR that uses organic EL elements.

[0006] [Patent Document 1] International Publication No. 2018 / 087625 Summary of the Invention

[0007] One objective of one embodiment of the present invention is to provide a display device with high resolution. Another objective of one embodiment of the present invention is to provide a display device with high aperture ratio. Another objective of one embodiment of the present invention is to provide a display device with high brightness. Another objective of one embodiment of the present invention is to provide a display device with high contrast. Another objective of one embodiment of the present invention is to provide a display device with high reliability.

[0008] One objective of one embodiment of the present invention is to provide a display device with a novel structure. Another objective of one embodiment of the present invention is to provide a method for manufacturing a novel display device. Another objective of one embodiment of the present invention is to provide a method for manufacturing the aforementioned display device with high yield. Finally, another objective of one embodiment of the present invention is to improve at least one of the problems of the prior art.

[0009] Note that the description of these objectives does not preclude the existence of other objectives. Also note that one embodiment of the present invention does not need to achieve all of the above objectives. Furthermore, objectives other than those described above can be derived from the description in the specification, drawings, claims, etc.

[0010] One embodiment of the present invention is a display device, including a first light-emitting element and a second light-emitting element. The first light-emitting element has a first pixel electrode, a first light-emitting layer, and a common electrode sequentially stacked thereon. The second light-emitting element has a second pixel electrode, a second light-emitting layer, and a common electrode sequentially stacked thereon. A first layer and a second layer are included in the region between the first and second light-emitting elements. The first layer overlaps with the second light-emitting layer and contains the same material as the first light-emitting layer. The second layer overlaps with the first light-emitting layer and contains the same material as the second light-emitting layer. In the region between the first and second light-emitting elements, the ends of the first light-emitting layer are opposite to the ends of the first layer. In the region between the first and second light-emitting elements, the ends of the second light-emitting layer are opposite to the ends of the second layer.

[0011] Another embodiment of the present invention is a display device, including a first light-emitting element and a second light-emitting element. The first light-emitting element has a first pixel electrode, a first light-emitting layer, a first intermediate layer, a third light-emitting layer, and a common electrode stacked sequentially. The second light-emitting element has a second pixel electrode, a second light-emitting layer, a second intermediate layer, a fourth light-emitting layer, and a common electrode stacked sequentially. Between the first and second light-emitting elements are a first layer, a second layer, a third layer, and a fourth layer. The first layer overlaps with the second, second, second, and fourth light-emitting layers and contains the same material as the first light-emitting layer. The second layer overlaps with the first, first, first, and third light-emitting layers and contains the same material as the second light-emitting layer. The third layer overlaps with the first layer and contains the same material as the third light-emitting layer. The fourth layer overlaps with the second layer and contains the same material as the fourth light-emitting layer. In the region between the first and second light-emitting elements, the ends of the first light-emitting layers face each other. In the region between the first and second light-emitting elements, the ends of the second light-emitting layers face each other. In the region between the first and second light-emitting elements, the ends of the third light-emitting layers face each other. In the region between the first light-emitting element and the second light-emitting element, the end of the fourth light-emitting layer is opposite to the end of the fourth layer.

[0012] In the above-described display device, preferably, the first light-emitting layer and the third light-emitting layer comprise the same material, and the second light-emitting layer and the fourth light-emitting layer comprise the same material.

[0013] In any of the aforementioned display devices, a resin layer is preferably further included. This resin layer is preferably located in the region between the first light-emitting element and the second light-emitting element. Preferably, the ends of the first light-emitting layer are opposite to the ends of the first layer separated by the resin layer, and the ends of the second light-emitting layer are opposite to the ends of the second layer separated by the resin layer.

[0014] In any of the aforementioned display devices, a first insulating layer is preferably also included. This first insulating layer is preferably located in the region between the first light-emitting element and the second light-emitting element. Preferably, the first insulating layer contacts the ends of the first light-emitting layer, the ends of the second light-emitting layer, the ends of the first layer, and the ends of the second layer.

[0015] Another embodiment of the present invention is a method for manufacturing a display device, comprising: a first process of forming a first pixel electrode and a second pixel electrode in an arranged manner; a second process of forming an island-shaped first light-emitting layer on the first pixel electrode using a first metal mask; a third process of forming an island-shaped second light-emitting layer on the second pixel electrode using a second metal mask in a manner overlapping the end of the first light-emitting layer; a fourth process of dividing the first light-emitting layer and the second light-emitting layer respectively by etching in the region between the first pixel electrode and the second pixel electrode; and a fifth process of forming a common electrode by covering the first light-emitting layer and the second light-emitting layer.

[0016] In the above method, a sixth process is included after the fourth process and before the fifth process, in which a resin layer is formed within the slit formed by etching.

[0017] In the above method, a photosensitive organic resin is preferably used as the resin layer.

[0018] In any of the above methods, it is preferable to include a seventh process after the fourth process and before the sixth process, in which the first insulating layer is formed by contacting the side surfaces of the first light-emitting layer and the second light-emitting layer exposed by etching.

[0019] In the above method, an inorganic insulating film formed by atomic layer deposition is preferably used as the first insulating layer.

[0020] According to one embodiment of the present invention, a display device with high resolution can be provided. Additionally, according to one embodiment of the present invention, a display device with high aperture ratio can be provided. Furthermore, according to one embodiment of the present invention, a display device with high brightness can be provided. Furthermore, according to one embodiment of the present invention, a display device with high contrast ratio can be provided. Furthermore, according to one embodiment of the present invention, a display device with high reliability can be provided.

[0021] According to one embodiment of the present invention, a display device with a novel structure can be provided. Furthermore, according to one embodiment of the present invention, a method for manufacturing the novel display device can be provided. Additionally, according to one embodiment of the present invention, a method for manufacturing the aforementioned display device with high yield can be provided. According to one embodiment of the present invention, at least one of the problems of the prior art can be improved.

[0022] Note that the description of these effects does not preclude the existence of other effects. Also note that one embodiment of the present invention does not necessarily require all of the above-described effects. Furthermore, effects other than those described above can be derived from the description in the specification, drawings, claims, etc. Simple Explanation of the Diagram

[0023] Figures 1A to 1D are diagrams illustrating examples of the structure of a display device. Figures 2A to 2C are diagrams showing examples of the structure of a display device. Figures 3A and 3B are diagrams illustrating examples of the structure of a display device. Figures 4A and 4B are diagrams illustrating examples of the structure of a display device. Figures 5A and 5B are diagrams illustrating examples of the structure of a display device. [Figure 6A] and [Figure 6B] are diagrams showing examples of the structure of a display device. [Figure 7A] and [Figure 7B] are diagrams showing examples of the structure of a display device. Figures 8A to 8C are figures illustrating examples of manufacturing methods for display devices. Figures 9A to 9C are illustrations showing examples of manufacturing methods for display devices. Figures 10A to 10C are figures illustrating examples of manufacturing methods for display devices. Figures 11A to 11C are diagrams illustrating examples of manufacturing methods for display devices. Figures 12A to 12C are illustrations of examples of manufacturing methods for display devices. [Figure 13] is a perspective view showing an example of a display device. [Figure 14A] is a cross-sectional view showing an example of a display device. [Figure 14B] is a cross-sectional view showing an example of a transistor. Figures 15A to 15E are diagrams illustrating an example of pixels in a display device. Figures 16A through 16G are diagrams illustrating an example of pixels in a display device. Figures 17A to 17F are diagrams showing examples of the structure of a light-emitting device. Figures 18A to 18D are diagrams illustrating an example of a pixel in a display device. Figures 18E and 18F are diagrams illustrating an example of a circuit for a pixel in a display device. Figures 19A to 19J are diagrams showing examples of the structure of a display device. [Figure 20A] and [Figure 20B] are figures illustrating an example of an electronic device. Figures 21A through 21D are diagrams illustrating an example of an electronic device. Figures 22A through 22F are illustrations of an example of an electronic device. Figures 23A through 23F are illustrations of an example of an electronic device. [Figure 24] is a graph showing the relationship between the screen size and pixel density of a product. Implementation

[0024] The embodiments will now be described with reference to the accompanying drawings. However, those skilled in the art will readily understand that the embodiments can be implemented in many different forms, and their manner and details can be varied in various ways without departing from the spirit and scope of the invention. Therefore, the invention should not be construed as being limited to the contents described in the embodiments shown below.

[0025] Note that in the structure of the invention described below, the same element symbols are used in different figures to represent the same parts or parts with the same function, and repeated descriptions are omitted. Furthermore, when representing parts with the same function, the same shading lines are sometimes used without additional element symbols.

[0026] Note that in the various figures described in this specification, the size of components, the thickness of layers, and areas are sometimes exaggerated for clarity. Therefore, the invention is not limited to the dimensions shown in the figures.

[0027] The ordinal numbers such as "first" and "second" used in this specification are appended to avoid confusion of components, and are not intended to limit the number of components.

[0028] In this specification and other materials, the terms "film" and "layer" may be interchanged. For example, "conductive layer" may sometimes be replaced with "conductive film". Furthermore, for example, "insulating layer" may sometimes be replaced with "insulating film".

[0029] Note that in this specification, the EL layer refers to a layer disposed between a pair of electrodes of a light-emitting element and including at least a light-emitting material (also called a light-emitting layer) or a stack including a light-emitting layer.

[0030] In this specification and the like, the display panel of one embodiment of the display device refers to a panel capable of displaying (outputting) images, etc., on a display surface. Therefore, the display panel is one embodiment of the output device.

[0031] Furthermore, in this specification and the like, a structure in which connectors such as FPC (Flexible Printed Circuit) or TCP (Tape Carrier Package) are mounted on the substrate of the display panel, or a structure in which ICs (Integrated Circuits) are directly mounted on the substrate in the form of COG (Chip On Glass), is sometimes referred to as a display panel module or display module, or simply as a display panel, etc.

[0032] Implementation Method 1 In this embodiment, an example of the structure of a display device according to one embodiment of the present invention and an example of a method for manufacturing the display device are described.

[0033] One embodiment of the present invention is a display device including light-emitting elements (also called light-emitting devices). The display device includes at least two light-emitting elements that emit different colors. Each light-emitting element includes a pair of electrodes and an EL layer between the pair of electrodes. The light-emitting elements are preferably organic EL elements (organic electric field light-emitting elements). Two or more light-emitting elements emitting different colors each include an EL layer containing different materials. For example, a full-color display device can be realized by including three light-emitting elements that respectively emit red (R), green (G), or blue (B) light.

[0034] Here, it is known that when forming part or all of an EL layer between light-emitting elements of different colors, the layer is formed by vapor deposition using a shadow mask such as a fine metal mask (FMM). However, this method is not easy to achieve high resolution and high aperture ratio in display devices because the shape and position of the island-shaped organic film differ from the design due to various influences such as the precision of the FMM, the misalignment between the FMM and the substrate, the deflection of the FMM, and the enlargement of the outline of the deposited film caused by vapor scattering. Therefore, measures have been taken to improve resolution (also known as pixel density) by adopting special pixel arrangement methods such as Pentile arrangement.

[0035] In the manufacturing process using FMM (Foil-Modified Metal) films, to achieve high resolution and high aperture ratio, two adjacent island-shaped organic films can be partially overlapped. This significantly reduces the distance between the light-emitting areas compared to cases where the two island-shaped organic films do not overlap. However, when adjacent island-shaped organic films are formed in an overlapping manner, current leakage sometimes occurs between the two adjacent light-emitting elements through the overlapping organic films, resulting in unintended light emission. This leads to decreased brightness, decreased contrast, and a deterioration in display quality. Furthermore, power efficiency and power consumption decrease due to leakage current.

[0036] Therefore, in one embodiment of the present invention, each organic film is formed using an open-film mirror (FMM) by overlapping portions of the organic films between two adjacent light-emitting elements. Specifically, each organic film is formed using an FMM to contain at least one light-emitting organic compound (also called a light-emitting layer). In this case, other organic films constituting the light-emitting elements can use a common film and do not need to be formed separately. In the region between two adjacent light-emitting elements, there is an organic laminate film with at least two light-emitting layers and other organic films stacked on top of each other. Then, the portion of the organic laminate film located between two adjacent light-emitting elements is etched using photolithography, thereby separating the organic laminate film. This interrupts the leakage path (leakage channel) of current between two adjacent light-emitting elements. This results in improvements in brightness, contrast, power efficiency, or power consumption.

[0037] Furthermore, to protect the sides of the organic laminate film exposed by etching, it is preferable to form an insulating layer. This can improve the reliability of the display device.

[0038] Thus, according to one embodiment of the present invention, a display device with micro-light-emitting elements integrated into the display can be realized. For example, without employing a special pixel arrangement such as the Pentile method to improve clarity, a display device can be realized that employs a so-called stripe arrangement in which R, G, and B are arranged in a column and has a clarity of 300 ppi or more, 500 ppi or more, 700 ppi or more, or 1000 ppi or more. Furthermore, a display device with an effective light-emitting area ratio (aperture ratio) of 15% or more, 20% or more, or even 30% or more, and less than 100% can be realized.

[0039] Furthermore, according to one embodiment of the present invention, miniature light-emitting elements can be manufactured with high precision, thus enabling complex pixel arrangement methods. For example, in addition to stripe arrangements, various arrangement methods such as S-stripes, Bayer arrangements, and Delta arrangements can also be used.

[0040] In this specification, the effective light-emitting area ratio refers to the ratio of the area of ​​the region that can be considered as the light-emitting area within a pixel to the area of ​​a pixel calculated from the pixel pitch of the display device.

[0041] The following describes a more specific structural example and manufacturing method example of a display device according to one embodiment of the present invention with reference to the drawings.

[0042] [Structure Example 1] Figure 1A shows a top view of a display device 100 according to an embodiment of the present invention. The display device 100 includes a plurality of light-emitting elements 110R that emit red light, a plurality of light-emitting elements 110G that emit green light, and a plurality of light-emitting elements 110B that emit blue light. In Figure 1A, to simply distinguish each light-emitting element, the symbols R, G, and B are attached to the light-emitting area of ​​each light-emitting element.

[0043] Light-emitting elements 110R, 110G, and 110B are all arranged in a matrix. Figure 1A shows a so-called stripe arrangement in which light-emitting elements emitting the same color are arranged in one direction. Note that the arrangement of light-emitting elements is not limited to this; arrangements such as S-stripes, Delta, Bayer, or zigzag arrangements can be used, as well as Pentile arrangements.

[0044] Light-emitting elements 110R, 110G, and 110B are arranged in the X direction. Additionally, light-emitting elements emitting the same color are arranged in the Y direction, which intersects the X direction.

[0045] As light-emitting elements 110R, 110G, and 110B, it is preferable to use EL devices such as OLED (Organic Light Emitting Diode) or QLED (Quantum-dot Light Emitting Diode). Examples of light-emitting materials contained in EL devices include fluorescent materials, phosphorescent materials, and materials exhibiting thermally activated delayed fluorescence (TADF) materials. In addition to organic compounds, inorganic compounds (quantum dot materials, etc.) can also be used as light-emitting materials in EL devices.

[0046] Figure 1B is a cross-sectional view corresponding to the dashed line A1-A2 in Figure 1A, and Figure 1C is a cross-sectional view corresponding to the dashed line B1-B2.

[0047] Figure 1B shows cross-sections of light-emitting elements 110R, 110G, and 110B. Light-emitting element 110R includes a pixel electrode 111R, organic layers 115, 112R, 116, 114, and a common electrode 113. Light-emitting element 110G includes a pixel electrode 111G, organic layers 115, 112G, 116, 114, and a common electrode 113. Light-emitting element 110B includes a pixel electrode 111B, organic layers 115, 112B, 116, 114, and a common electrode 113. Light-emitting elements 110R, 110G, and 110B share organic layer 114 and the common electrode 113. Organic layer 114 can also be considered a common layer.

[0048] The organic layer 112R of the light-emitting element 110R contains a light-emitting organic compound that emits at least red light. The organic layer 112G of the light-emitting element 110G contains a light-emitting organic compound that emits at least green light. The organic layer 112B of the light-emitting element 110B contains a light-emitting organic compound that emits at least blue light. Organic layers 112R, 112G, and 112B may each be referred to as light-emitting layers.

[0049] Hereinafter, when describing the common features among light-emitting elements 110R, 110G, and 110B, they will sometimes be referred to as light-emitting element 110. Similarly, when describing the common features among components such as organic layers 112R, 112G, and 112B, which are distinguished by letters, symbols with omitted letters will sometimes be used.

[0050] The stacked film located between the pixel electrode and the common electrode 113 in each light-emitting element can be called the EL layer.

[0051] In each light-emitting element, organic layer 115 is located between organic layer 112 and pixel electrode 111. Additionally, organic layer 116 is located between organic layer 112 and organic layer 114. Organic layer 114 is located between organic layer 116 and common electrode 113.

[0052] Organic layers 115, 116, and 114 may each independently include one or more of an electron injection layer, an electron transport layer, a hole injection layer, and a hole transport layer. For example, the following structure may be adopted: organic layer 115 has a stacked structure including a hole injection layer and a hole transport layer from the pixel electrode 111 side, organic layer 116 includes an electron transport layer, and organic layer 114 includes an electron injection layer. Alternatively, the following structure may be adopted: organic layer 115 has a stacked structure including an electron injection layer and an electron transport layer from the pixel electrode 111 side, organic layer 116 includes a hole transport layer, and organic layer 114 includes a hole injection layer.

[0053] Note that regarding organic layers 112, 114, 115, and 116, which are located between a pair of electrodes in the light-emitting element, "organic layer" means the layer that constitutes the organic EL element and does not necessarily contain organic compounds. For example, organic layers 112, 114, 115, and 116 may not contain organic compounds and may use films containing only inorganic compounds or inorganic materials.

[0054] Pixel electrodes 111R, 111G, and 111B are provided for each light-emitting element. Furthermore, the common electrode 113 and the organic layer 114 are a single layer shared by all light-emitting elements. Either the pixel electrode or the common electrode 113 uses a conductive film that is transparent to visible light, while the other uses a reflective conductive film. By making each pixel electrode transparent and the common electrode 113 reflective, a bottom-emitting (bottom-emitting structure) display device can be realized. Conversely, by making each pixel electrode reflective and the common electrode 113 transparent, a top-emitting (top-emitting structure) display device can be realized. Furthermore, by making both the pixel electrode and the common electrode 113 transparent, a double-sided emitting (double-sided emitting structure) display device can be realized.

[0055] A protective layer 121 is provided on the common electrode 113 to cover the light-emitting elements 110R, 110G, and 110B. The protective layer 121 has the function of preventing water and other impurities from diffusing from above to each light-emitting element.

[0056] A slit 120 is provided between two adjacent light-emitting elements. The slit 120 corresponds to the portion of the organic layers 115, 112 and 116 located between the two adjacent light-emitting elements that has been etched.

[0057] An insulating layer 125 and a resin layer 126 are disposed in the slit 120. The insulating layer 125 is disposed along the sidewalls and bottom surface of the slit 120. The resin layer 126 is disposed on the insulating layer 125 and has the function of filling the recess of the slit 120 to flatten the top surface of the slit. By flattening the recess of the slit 120 by the resin layer 126, the coverage of the organic layer 114, the common electrode 113, and the protective layer 121 can be improved. In addition, the slit 120 can be formed at the same time as the opening of the external connection terminal such as the connecting electrode 111C, so that they can be formed without increasing the process. In addition, since the slit 120 includes the insulating layer 125 and the resin layer 126, it plays a role in preventing short circuits between the pixel electrode 111 and the common electrode 113. In addition, the resin layer 126 plays a role in improving the adhesion of the organic layer 114. In other words, by providing the resin layer 126, the adhesion of the organic layer 114 is improved, thus suppressing the peeling of the organic layer 114. Furthermore, the insulating layer 125 is provided in contact with the side surface of the organic layer (e.g., organic layer 115), so the organic layer does not need to contact the resin layer 126. When the organic layer contacts the resin layer 126, the organic layer may sometimes dissolve due to organic solvents contained in the resin layer 126. Therefore, as shown in this embodiment, by providing the insulating layer 125 between the organic layer and the resin layer 126, the side surface of the organic layer can be protected. Additionally, the slit 120 may have at least one or more of the following structures: a hole injection layer, a hole transport layer, an electron suppression layer, a light-emitting layer, a hole suppression layer, an electron transport layer, and an electron injection layer.

[0058] The insulating layer 125 can be an insulating layer containing inorganic materials. Inorganic insulating films such as oxide insulating films, nitride insulating films, oxynitride insulating films, and oxynitride insulating films can be used as the insulating layer 125. The insulating layer 125 can be a single-layer structure or a multilayer structure. Examples of oxide insulating films include silicon oxide films, aluminum oxide films, magnesium oxide films, indium gallium zinc oxide films, gallium oxide films, germanium oxide films, yttrium oxide films, zirconium oxide films, lanthanum oxide films, neodymium oxide films, hafnium oxide films, and tantalum oxide films. Examples of nitride insulating films include silicon nitride films and aluminum nitride films. Examples of oxynitride insulating films include silicon oxynitride films and aluminum oxynitride films. Examples of oxynitride insulating films include silicon oxynitride films and aluminum oxynitride films. In particular, by using inorganic insulating films such as alumina film, hafnium oxide film, and silicon oxide film formed by the ALD method for insulating layer 125, an insulating layer 125 with fewer pinholes and excellent protection of the EL layer can be formed.

[0059] In this specification, etc., "oxynitride" refers to a material in which the oxygen content is greater than the nitrogen content in its composition, while "nitrogen oxide" refers to a material in which the nitrogen content is greater than the oxygen content in its composition. For example, "silicon oxynitride" refers to a material in which the oxygen content is greater than the nitrogen content in its composition, while "silicon oxynitride" refers to a material in which the nitrogen content is greater than the oxygen content in its composition.

[0060] The insulating layer 125 can be formed using sputtering, CVD, PLD, ALD, or other methods. Preferably, the insulating layer 125 is formed using the ALD method, which has excellent coverage.

[0061] As resin layer 126, an insulating layer containing organic materials can be suitable. For example, acrylic resin, polyimide resin, epoxy resin, imide resin, polyimide resin, polyimide-polyamide resin, silicone resin, silicone resin, benzocyclobutene resin, phenolic resin, and precursors of the above resins can be used as resin layer 126. Alternatively, as resin layer 126, organic materials such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinylpyrrolidone, polyethylene glycol, polyglycerol, pullulan, water-soluble cellulose, or alcohol-soluble polyimide resin can also be used. Furthermore, photosensitive resin can also be used as resin layer 126. Photoresist can also be used as photosensitive resin. Positive or negative materials can also be used as photosensitive resin. Additionally, by using a colored material (e.g., a material containing black pigment) as resin layer 126, the function of suppressing color mixing by blocking stray light from adjacent pixels can be added. Alternatively, a reflective film (e.g., a metal film selected from one or more of silver, palladium, copper, titanium, and aluminum) can be provided between the insulating layer 125 and the resin layer 126 to add the function of reflecting the light emitted by the light-emitting layer and improving the light extraction efficiency.

[0062] The flatter the top surface of resin layer 126, the better, but sometimes it is a gently curved shape. Figure 1B shows an example of a wavy shape with concave and convex portions on the top surface of resin layer 126, but it is not limited to this. For example, the top surface of resin layer 126 can be a convex surface, a concave surface, or a plane.

[0063] The protective layer 121 can also be a laminate of an inorganic insulating film and an organic insulating film. For example, it is preferable to sandwich an organic insulating film between a pair of inorganic insulating films. Furthermore, the organic insulating film is preferably used as a planarization film. Therefore, the top surface of the organic insulating film can be flattened, thus improving the coverage of the inorganic insulating film thereon and thereby enhancing its barrier properties. Additionally, the flattened top surface of the protective layer 121 reduces the influence of the uneven shape of the underlying structure when structures (e.g., color filters, electrodes of touch sensors, or lens arrays) are placed above the protective layer 121, which is preferable.

[0064] The protective layer 121 may, for example, have a single-layer structure or a multilayer structure comprising at least an inorganic insulating film. Examples of inorganic insulating films include oxide films or nitride films such as silicon oxide films, silicon oxynitride films, silicon oxynitride films, silicon nitride films, aluminum oxide films, aluminum oxynitride films, and hafnium oxide films. Alternatively, semiconductor materials such as indium gallium oxide and indium gallium zinc oxide may be used as the protective layer 121.

[0065] As shown in Figure 1C, slits 120 can also be provided between light-emitting elements of the same color. By providing slits 120 between light-emitting elements of the same color, unintended light emission can be prevented from occurring due to current flowing through adjacent EL layers. This improves contrast, thus enabling a display device with high display quality.

[0066] In the Y direction, organic layers 112R, 112G, or 112B can also be formed into strips so that each organic layer 112R, 112G, or 112B is continuous between light-emitting elements of the same color. By forming organic layers 112R, etc., into strips, there is no need to divide their space, which can reduce the area of ​​non-light-emitting regions between light-emitting elements, thus increasing the aperture ratio.

[0067] Additionally, Figure 1A shows a connecting electrode 111C electrically connected to the common electrode 113. The connecting electrode 111C is supplied with a potential (e.g., anode potential or cathode potential) for supplying the common electrode 113. The connecting electrode 111C is disposed outside the display area where the light-emitting elements 110R, etc., are arranged. Furthermore, in Figure 1A, the common electrode 113 is indicated by a dashed line.

[0068] The connection electrode 111C can be provided along the outer periphery of the display area. For example, it can be provided along one side of the outer periphery of the display area, or can be provided across two or more sides of the outer periphery of the display area. That is, when the top surface shape of the display area is square, the top surface shape of the connection electrode 111C can be strip-shaped, L-shaped, "冂" - shaped (square bracket-shaped), or quadrangular, etc.

[0069] FIG. 1D is a schematic cross-sectional view corresponding to the dotted line C1 - C2 in FIG. 1A. FIG. 1D shows the connection portion 130 where the connection electrode 111C is electrically connected to the common electrode 113. In the connection portion 130, the common electrode 113 is provided on the connection electrode 111C with an organic layer 114 interposed therebetween. In addition, an insulating layer 125 is provided in contact with the side surface of the connection electrode 111C, and a resin layer 126 is provided on the insulating layer 125.

[0070] Note that the organic layer 114 may not be provided in the connection portion 130. At this time, in the connection portion 130, the common electrode 113 is provided in contact with the connection electrode 111C on the connection electrode 111C, and a protective layer 121 is provided to cover the common electrode 113.

[0071] FIGS. 2A, 2B, and 2C show examples of the case where the insulating layer 125 is not provided.

[0072] As shown in FIGS. 2A and 2B, the resin layer 126 is provided in contact with the side surfaces of the organic layer 115, the organic layer 112, and the organic layer 116. In addition, as shown in FIG. 2C, the resin layer 126 is provided in contact with the side surface of the connection electrode 111C.

[0073] Next, the suitable structure of the slit 120 and its vicinity will be described in detail. FIG. 3A is a schematic cross-sectional view including a part of the light-emitting element 110R in FIG. 1B, a part of the light-emitting element 110G, and the area therebetween.

[0074] As shown in FIG. 3A, the end portion of the pixel electrode 111 preferably has a tapered shape. Thereby, the step coverage of the organic layer 115, etc. can be improved. Note that in this specification, etc., "the end portion of an object has a tapered shape" means having the following cross-sectional shape: in the area of its end portion, the angle formed by the surface and the formed surface is greater than 0° and less than 90°; and its thickness gradually increases from the end portion. Although the case where the pixel electrode 111R, etc. has a single-layer structure is shown here, multiple layers may also be stacked.

[0075] An organic layer 115 is provided on the pixel electrode 111R. Additionally, an organic layer 115 is provided on the pixel electrode 111G. The organic layer 115 is formed by dividing a continuous film by a slit 120.

[0076] On the side where the light-emitting element 110R is positioned relative to slit 120, an organic layer 112R is provided on the organic layer 115. Additionally, on the side where the light-emitting element 110G is positioned relative to slit 120, a layer 135R is provided on the organic layer 115. Layer 135R can also be considered a fragment that, as part of the organic layer 112R, is separated by slit 120 and remains on the side of the light-emitting element 110G.

[0077] Furthermore, on the side where the light-emitting element 110G is disposed with reference to slit 120, an organic layer 112G is disposed on top of the organic layer 115. Additionally, on the side where the light-emitting element 110R is disposed with reference to slit 120, a layer 135G is disposed on the organic layer 112R. Layer 135G can also be considered as a fragment that, as part of the film of organic layer 112G, is separated by slit 120 and remains on the side of the light-emitting element 110R.

[0078] Note that, depending on the position and width of the slit 120, the position where the organic layer 112R is formed, and the position where the organic layer 112G is formed, sometimes one or both of layers 135R and 135G may not be formed. Specifically, if the end of the organic layer 112R before the formation of the slit 120 overlaps with the position where the slit 120 is formed, sometimes layer 135R may not be formed.

[0079] Organic layer 116 is provided on organic layers 112R and 135G. Similarly, organic layer 116 is provided on organic layers 112G and 135R. Like organic layer 115, organic layer 116 is formed by dividing a continuous film by slits 120.

[0080] An insulating layer 125 is disposed inside the slit 120 and is disposed in such a manner that it contacts the side surfaces of a pair of organic layers 115, the side surfaces of organic layers 112R, 112G, 135R, 135G, and a pair of organic layers 116. In addition, the insulating layer 125 is disposed in such a manner that it covers the top surface of the substrate 101.

[0081] The resin layer 126 is disposed in contact with the top and side surfaces of the insulating layer 125. The resin layer 126 has the function of planarizing the recesses on the surfaces where the organic layer 114 is formed.

[0082] An organic layer 114, a common electrode 113, and a protective layer 121 are sequentially formed on the top surface covering the organic layer 116, the insulating layer 125, and the resin layer 126. Note that the organic layer 114 can be omitted if not needed.

[0083] Here, layers 135R and 135G are portions located at the ends of the film that will become organic layer 112R or organic layer 112G. In the FMM deposition method, the thickness of the organic film tends to become thinner closer to the ends, so layers 135R and 135G have portions that are thinner than organic layer 112R or organic layer 112G. Sometimes layers 135R and 135G are so thin that they cannot be detected in cross-sectional observation. In addition, even if layers 135R or 135G are present, it is sometimes difficult to confirm the boundary between layer 135R and organic layer 112G, or the boundary between layer 135G and organic layer 112R, in cross-sectional observation.

[0084] On the other hand, layers 135R and 135G contain luminescent compounds (e.g., fluorescent materials, phosphorescent materials, or quantum dots), so by irradiating the plane with ultraviolet or visible light, photoluminescence can be obtained. The presence of layers 135R and 135G can be confirmed by observing this luminescence using an optical microscope. Specifically, because layer 135R overlaps with organic layer 112G in the portion where it is disposed, both light from layer 135R and light from organic layer 112G can be observed when ultraviolet light is irradiated onto that portion. Furthermore, based on the emission spectrum, wavelength, and color of the light emitted from layers 135R and 135G, it can be confirmed that layers 135R or 135G contain the same material as organic layer 112R or 112G. Additionally, the compounds contained in layers 135R and 135G can sometimes be inferred.

[0085] Note that this example illustrates the use of an FMM to form organic layers 112R and 112G separately, and other organic layers (organic layers 115 and 116) into a continuous film, but is not limited to this. For example, one or both of organic layers 115 and 116 can also be formed separately using an FMM. In this case, fragments of organic layer 115 or organic layer 116 may sometimes remain near slit 120, similar to those in layer 135R.

[0086] Figure 3B is a cross-sectional schematic diagram excluding the insulating layer 125. The resin layer 126 is disposed in such a way that it contacts the sides of a pair of organic layers 115, the sides of organic layer 112R, the sides of organic layer 112G, the sides of layer 135R, the sides of layer 135G, and the sides of a pair of organic layers 116.

[0087] At this time, sometimes a portion of the EL layer dissolves due to the solvent used in forming the film that will become the resin layer 126. Therefore, when the insulating layer 125 is not provided, it is preferable to use water, or alcohols such as ethyl alcohol, methyl alcohol, isopropyl alcohol (IPA), or glycerol as the solvent for the resin layer 126. Note that this is not a limitation; any solvent that does not dissolve or does not readily dissolve the EL layer may be used.

[0088] The enlarged views shown in Figures 3A and 3B illustrate the light-emitting elements 110R, 110G, and the area between them, but the same structure also exists between light-emitting elements 110R and 110B, and between light-emitting elements 110G and 110B.

[0089] [Structure Example 2] Compared to a single-layer light-emitting layer, stacking multiple light-emitting layers allows for higher brightness emission when the same current flows. Furthermore, it reduces the current density required to achieve the same brightness, thus improving reliability. An example of stacked light-emitting layers is described below.

[0090] Figure 4A is a schematic cross-sectional view of the display device illustrated below. The display device includes light-emitting element 110R, light-emitting element 110G, and light-emitting element 110B. The light-emitting elements 110R, 110G, and 110B shown in Figure 4A are all light-emitting elements with a so-called series structure, in which two light-emitting layers are stacked with a charge generation layer (also called an intermediate layer) in between.

[0091] Light-emitting element 110R has a structure in which an organic layer 115, an organic layer 112R1, an organic layer 116, a charge generation layer 117, an organic layer 118, an organic layer 112R2, an organic layer 119, an organic layer 114, and a common electrode 113 are stacked on a pixel electrode 111R. Similarly, light-emitting element 110G includes a pixel electrode 111G, an organic layer 115, an organic layer 112G1, an organic layer 116, a charge generation layer 117, an organic layer 118, an organic layer 112G2, an organic layer 119, an organic layer 114, and a common electrode 113. In addition, light-emitting element 110B includes a pixel electrode 111B, an organic layer 115, an organic layer 112B1, an organic layer 116, a charge generation layer 117, an organic layer 118, an organic layer 112B2, an organic layer 119, an organic layer 114, and a common electrode 113.

[0092] A slit 120 is provided between two adjacent light-emitting elements. The slit 120 is formed in a stacked structure that divides the region between the two pixel electrodes by organic layers 115 to 119. Furthermore, an insulating layer 125 and a resin layer 126 are provided inside the slit 120. Note that the insulating layer 125 may also be omitted.

[0093] Figure 4B is a cross-sectional schematic diagram including a portion of the light-emitting element 110R, a portion of the light-emitting element 110G, and the area between them, as shown in Figure 4A.

[0094] On the side where the light-emitting element 110R is disposed with reference to slit 120, a layer 135G1 is disposed between organic layer 115 and organic layer 116. In addition, a layer 135G2 is disposed between organic layer 118 and organic layer 119.

[0095] On the side where the light-emitting element 110G is disposed with reference to slit 120, a layer 135R1 is disposed between organic layer 115 and organic layer 116. In addition, a layer 135R2 is disposed between organic layer 118 and organic layer 119.

[0096] Layers 135R1 and 135R2 can also be considered as fragments that would become part of the film of organic layer 112R1 or organic layer 112R2, separated by slit 120 and remaining on the side of the light-emitting element 110G. Similarly, layers 135G1 and 135G2 can also be considered as fragments that would become part of the film of organic layer 112G1 or organic layer 112G2, separated by slit 120 and remaining on the side of the light-emitting element 110R.

[0097] The side of layer 135R1 faces the side of organic layer 112R1 across resin layer 126 (and insulating layer 125). The same applies to layer 135R2 and organic layer 112R2, layer 135G1 and organic layer 112G1, and layer 135G2 and organic layer 112G2, with each side facing each other across resin layer 126 (and insulating layer 125).

[0098] Note that sometimes more than one of the layers 135R1, 135R2, 135G1, and 135G2 is not set.

[0099] The stacking order of organic layer 112R1 and layer 135G1, the stacking order of organic layer 112R2 and layer 135G2, the stacking order of organic layer 112G1 and layer 135R1, and the stacking order of organic layer 112G2 and layer 135R2 each depend on the stacking order of organic layer 112R1 and organic layer 112G1 or the stacking order of organic layer 112R2 and organic layer 112G2, and there is no restriction on the order.

[0100] A charge generation layer 117 is disposed between the two light-emitting layers (organic layer 112R1 and organic layer 112R2) included in the light-emitting element. An organic layer 118 is disposed between the charge generation layer 117 and the organic layer 112R2. An organic layer 119 is disposed between the organic layer 112R2 and the organic layer 114. Organic layers 118 and 119 may each independently include one or more of an electron injection layer, an electron transport layer, a hole injection layer, and a hole transport layer.

[0101] The stacked structures of organic layers 115 to 116 and organic layers 118 to 114 can both be referred to as a light-emitting unit. The light-emitting element 110 shown in Figure 4A can be referred to as a light-emitting element having a series structure of two light-emitting units stacked with a charge-generating layer 117 separated by a charge generation layer.

[0102] [Example of variation] Figure 5A is a variation of Figure 3A. Figure 5A shows an example of a case where an insulating layer 131 is provided covering the end of the pixel electrode.

[0103] The insulating layer 131 has the function of planarizing the surface on which the organic layer 115 is formed. The ends of the insulating layer 131 are preferably tapered. Furthermore, by using an organic resin in the insulating layer 131, its surface can have a gentle curve. Therefore, the coverage of the film formed on the insulating layer 131 can be improved.

[0104] Materials that can be used for insulating layer 131 include, for example, acrylic resin, polyimide resin, epoxy resin, polyimide resin, polyimide resin, silicone resin, benzocyclobutene resin, phenolic resin, and precursors of these resins.

[0105] As shown in Figure 5A, the insulating layer 131 may also have a recess in the region overlapping with the slit 120. This recess is formed because a portion of the top of the insulating layer 131 is etched during the etching process used to form the slit 120. Because a portion of the insulating layer 125 is formed in this recess of the insulating layer 131, their adhesion can be improved.

[0106] The slit 120 is disposed in the region overlapping the insulating layer 131. In addition, layers 135R and 135G are also disposed in the region overlapping the insulating layer 131.

[0107] Figure 5B is an example of the case in Figure 4B above where insulating layer 131 is also used.

[0108] In Figure 5B, slit 120, layer 135R1, layer 135R2, layer 135G1 and layer 135G2 are all located in the region overlapping the insulating layer 131.

[0109] Figures 6A and 6B are examples of cases where an insulating layer 132 is provided on the insulating layer 131.

[0110] An insulating layer 132 overlaps the end of the pixel electrode 111, passing over an insulating layer 131. Furthermore, the insulating layer 132 covers the end of the insulating layer 131. Additionally, the insulating layer 132 has a portion that contacts the top surface of the pixel electrode 111.

[0111] The ends of the insulating layer 132 are preferably tapered. This improves the step coverage of films such as the EL layer formed on the insulating layer 132 that cover the ends of the insulating layer 132.

[0112] Furthermore, the thickness of insulating layer 132 is preferably thinner than that of insulating layer 131. By forming a thinner insulating layer 132, the step coverage of the film formed on insulating layer 132 can be improved.

[0113] As inorganic insulating materials that can be used in insulating layer 132, oxides or nitrides such as silicon oxide, silicon oxynitride, silicon oxynitride, silicon nitride, aluminum oxide, aluminum oxynitride, or hafnium oxide can be used. In addition, yttrium oxide, zirconium oxide, gallium oxide, tantalum oxide, magnesium oxide, lanthanum oxide, cerium oxide, and neodymium oxide can also be used.

[0114] Alternatively, the insulating layer 132 may also be laminated with a film containing the aforementioned inorganic insulating material. For example, a laminated structure in which a silicon oxide film or a silicon oxynitride film is laminated on a silicon nitride film, or a laminated structure in which a silicon oxide film or a silicon oxynitride film is laminated on an aluminum oxide film, etc. Silicon oxide film and silicon oxynitride film are films that are particularly difficult to etch, so they are preferably disposed on the upper side. In addition, silicon nitride film and aluminum oxide film are films that do not easily allow water, hydrogen, oxygen, etc. to diffuse, so by being disposed on the insulating layer 131 side, they are used as a barrier layer to prevent gases detached from the insulating layer 131 from diffusing into the light-emitting element.

[0115] The slit 120 is disposed in the region overlapping the insulating layer 132. In addition, layers 135R and 135G are also disposed in the region overlapping the insulating layer 132.

[0116] By providing the insulating layer 132, the top surface of the insulating layer 131 can be prevented from being etched when the slit 120 is formed.

[0117] Figure 6B is an example of the case in Figure 5B above where insulating layer 132 is also used.

[0118] In Figure 6B, slit 120, layer 135R1, layer 135R2, layer 135G1 and layer 135G2 are all located in the region overlapping the insulating layer 132.

[0119] [Structure Example 3] The following provides a more specific example of the structure.

[0120] Figure 7A is a cross-sectional schematic diagram of the display device illustrated below. Figure 7A shows a cross-section of the area including light-emitting element 110R, light-emitting element 110G, light-emitting element 110B, and connecting portion 130. In addition, Figure 7B is an enlarged cross-sectional schematic diagram of the slit 120 and its vicinity located between light-emitting element 110R and light-emitting element 110G.

[0121] In the structure shown in Figure 7A, a portion (fragment) of the organic layer 112B divided by the slit 120 is disposed near the light-emitting element 110R and near the light-emitting element 110G.

[0122] A conductive layer 161, a conductive layer 162, and a resin layer 163 are disposed below the pixel electrode 111.

[0123] A conductive layer 161 is disposed on an insulating layer 105. The conductive layer 161 has a portion penetrating the insulating layer 105 in an opening disposed in the insulating layer 105. The conductive layer 161 is used to electrically connect wiring, transistors, or electrodes (not shown) located below the insulating layer 105 to wiring or electrodes of the pixel electrode 111.

[0124] The portion of conductive layer 161 located at the opening of insulating layer 105 has a recess. Resin layer 163 is provided to fill the recess and serves as a planarization film. The flatter the top surface of resin layer 163, the better, but sometimes it is a gently curved shape. Figure 7A shows an example of a wavy shape with recesses and convexities on the top surface of resin layer 163, but it is not limited to this. For example, the top surface of resin layer 163 can be a convex surface, a concave surface, or a plane.

[0125] A conductive layer 162 is disposed on the conductive layer 161 and the resin layer 163. The conductive layer 162 is used as an electrode to electrically connect the conductive layer 161 and the pixel electrode 111.

[0126] Here, when the light-emitting element 110 is a top-emitting type light-emitting element, by using a film that is reflective to visible light as the conductive layer 162 and a film that is transmissive to visible light as the pixel electrode 111R, the conductive layer 162 can be used as a reflective electrode. Furthermore, since the conductive layer 162 and the pixel electrode 111 can be disposed on top of the opening (also called the contact portion) of the insulating layer 105 across the resin layer 163, the portion overlapping the contact portion can be used as the light-emitting area. Therefore, the aperture ratio can be improved.

[0127] Figures 7A and 7B show examples where the shape of resin layer 126 differs from that described above.

[0128] As shown in Figure 7B, the top of the resin layer 126 has a shape whose width is greater than the width of the slit 120. As described later, the insulating layer 125 is processed with the resin layer 126 as an etching mask, so a portion covered by the top of the resin layer 126 remains. Furthermore, a portion of the sacrificial layer 145 used in the manufacturing process of the display device also remains for the same reason. Specifically, the sacrificial layer 145 is provided on the organic layer 116 near the slit 120. Additionally, a portion of the insulating layer 125 is provided to cover the top surface of the sacrificial layer 145. Furthermore, the resin layer 126 is provided to cover both the sacrificial layer 145 and the insulating layer 125.

[0129] At this point, the ends of the insulating layer 125 and the sacrificial layer 145 are preferably tapered. This improves the step coverage of the organic layer 114, etc.

[0130] As shown in Figures 7A and 7B, layers 135R, 135G, and 135B are all in contact with insulating layer 125 and have regions that overlap with insulating layer 125, sacrificial layer 145, and resin layer 126.

[0131] [Example of manufacturing method] Hereinafter, an example of a method for manufacturing a display device according to an embodiment of the present invention will be described with reference to the drawings. The display device shown in FIG. 7A above will be used as an example for description. FIG. 8A to FIG. 11C are cross-sectional schematic diagrams of each process in the following example of the manufacturing method of the display device. Furthermore, a cross-sectional schematic diagram of the connecting portion 130 and its vicinity is also shown on the right side of FIG. 8A, etc.

[0132] Thin films (insulating films, semiconductor films, conductive films, etc.) constituting display devices can be formed using methods such as sputtering, chemical vapor deposition (CVD), vacuum evaporation, pulsed laser deposition (PLD), and atomic layer deposition (ALD). CVD methods include plasma-enhanced chemical vapor deposition (PECVD) and thermal CVD. Furthermore, metal-organic chemical vapor deposition (MOCVD) is one type of thermal CVD method.

[0133] In addition, the thin films (insulating films, semiconductor films, conductive films, etc.) constituting the display device can be formed using methods such as spin coating, dip coating, spray coating, inkjet coating, distributor coating, screen printing, flatbed printing, doctor knife coating, slot coating, roller coating, curtain coating, and doctor knife coating.

[0134] Furthermore, when processing the thin film constituting the display device, photolithography and other methods can be used. Besides the methods mentioned above, nanoimprinting, sandblasting, and peeling methods can also be used to process the thin film. Additionally, island-shaped thin films can be directly formed using shadow mask deposition methods such as metal masks.

[0135] Photolithography typically involves two methods. One method involves forming a photoresist mask on the film to be processed, then processing the film using etching or similar techniques, and finally removing the photoresist mask. The other method involves depositing a photosensitive film, followed by exposure and development to shape the film into the desired form.

[0136] In photolithography, the light used for exposure can be, for example, i-line (wavelength 365nm), g-line (wavelength 436nm), h-line (wavelength 405nm), or a mixture of these. Additionally, ultraviolet light, KrF lasers, or ArF lasers can also be used. Furthermore, immersion exposure techniques can be employed. Extreme ultraviolet (EUV) light or X-rays can also be used as the light for exposure. Alternatively, an electron beam can be used instead of the light used for exposure. Using EUV, X-rays, or electron beams allows for extremely fine processing and is therefore preferable. Note that when exposure is performed by scanning with a beam such as an electron beam, a photomask is not required.

[0137] As a method for etching thin films, dry etching, wet etching, and sandblasting can be used.

[0138] [Preparation of substrate 101] As substrate 101, a substrate with heat resistance sufficient to withstand subsequent heat treatment can be used. When using an insulating substrate as substrate 101, glass substrates, quartz substrates, sapphire substrates, ceramic substrates, organic resin substrates, etc., can be used. In addition, single-crystal semiconductor substrates or polycrystalline semiconductor substrates made of materials such as silicon or silicon carbide, compound semiconductor substrates made of materials such as silicon and germanium, SOI substrates, and other semiconductor substrates can also be used.

[0139] In particular, substrate 101 is preferably a substrate on which a semiconductor circuit including semiconductor elements such as transistors is formed on the aforementioned semiconductor substrate or insulating substrate. This semiconductor circuit is preferably, for example, a pixel circuit, a gate line drive circuit (gate driver), a source line drive circuit (gate driver), etc. In addition, it can also be configured as an arithmetic circuit, a memory circuit, etc.

[0140] An insulating layer 105 is provided at the top of the substrate 101. Multiple openings are provided in the insulating layer 105 to reach transistors, wiring, electrodes, etc. provided in the substrate 101. These openings can be formed by photolithography.

[0141] Inorganic or organic insulating materials can be used as the insulating layer 105.

[0142] [Formation of conductive layer 161, resin layer 163, conductive layer 162, and pixel electrode 111] A conductive film, which will become the conductive layer 161, is deposited on the insulating layer 105. At this time, a recess is formed in the conductive film due to the opening in the insulating layer 105.

[0143] Next, a resin layer 163 is formed on the recess of the conductive film.

[0144] Photosensitive resin is preferably used as resin layer 163. In this case, a resin film is first deposited, then exposed to light through a photomask, and then developed to form resin layer 163. The top of resin layer 163 can then be etched using methods such as ashing to adjust the height of the top surface of resin layer 163.

[0145] In addition, when a non-photosensitive resin is used as resin layer 163, after depositing the resin film, the top of the resin film is etched by ashing or the like until the surface of the conductive film that will become conductive layer 161 is exposed, so that the thickness of the resin layer is most suitable, thereby forming resin layer 163.

[0146] Next, a conductive film that will become conductive layer 162 is deposited on the conductive film that will become conductive layer 161 and the resin layer 163. Then, a photoresist mask is formed on the two conductive films by photolithography, and unwanted parts of the conductive films are removed by etching. Then, the photoresist mask is removed, thereby forming conductive layer 161 and conductive layer 162 in the same process.

[0147] Here, the same photomask is used to form conductive layer 161 and conductive layer 162 in the same process, but different photomasks can also be used to form conductive layer 161 and conductive layer 162 respectively.

[0148] Next, a conductive film is formed by covering conductive layers 161 and 162, and a portion of the conductive film is removed by etching, thereby forming pixel electrode 111 and connection electrode 111C (FIG. 8A). At this time, as shown in FIG. 8A, it is preferable to form pixel electrode 111 and connection electrode 111C by including conductive layers 161 and 162, so that conductive layers 161 and 162 are not exposed to the etching atmosphere during the formation of pixel electrode 111, etc.

[0149] [Formation of organic layer 115] Next, an organic layer 115 is deposited on the pixel electrode 111 (Figure 8B). The organic layer 115 is preferably deposited without using an FMM.

[0150] Note that FMM can also be used to form organic layer 115 separately. In this case, please refer to the description of organic layer 112R, etc. later.

[0151] The organic layer 115 is preferably formed using a vacuum evaporation method. Note that it is not limited to this method; it can also be formed using sputtering or inkjet printing. Furthermore, it is not limited to this method; the above-described deposition methods can be used appropriately.

[0152] [The formation of organic layer 112R, organic layer 112G, and organic layer 112B] Next, an island-shaped organic layer 112R is formed in such a way that it includes the region on the organic layer 115 and overlaps the pixel electrode 111R.

[0153] The organic layer 112R is preferably formed using vacuum evaporation via an FMM. Alternatively, island-shaped organic layers 112R can also be formed using sputtering or inkjet printing with an FMM.

[0154] Figure 8C shows the deposition of organic layer 112R using FMM151R. Figure 8C also shows the deposition process using a so-called facedown method, where the substrate is inverted with the surface to be formed facing down.

[0155] In methods such as evaporation using an open-circuit membrane (FMM), the evaporation layer is often deposited over an area larger than the opening pattern of the FMM. Therefore, as shown by the dashed line in FIG8C, even if an FMM151R with the same opening pattern as the pixel electrode 111R is used, the organic layer 112R can be deposited in the region between the pixel electrode 111R and the pixel electrode adjacent to the pixel electrode 111R.

[0156] Next, an organic layer 112G is formed on the pixel electrode 111G using an FMM151G (Figure 9A).

[0157] Similar to organic layer 112R, organic layer 112G can also be patterned to extend to the outside of pixel electrode 111G. As a result, as shown in region RG in FIG9A, a portion of organic layer 112G can be formed on organic layer 112R.

[0158] Next, an organic layer 112B is formed on the pixel electrode 111B using an FMM151B (Figure 9B).

[0159] Similar to organic layers 112R and 112G, organic layer 112B can also be patterned to extend to the outside of pixel electrode 111B. As a result, as shown in FIG9B, a region RB on organic layer 112R with organic layer 112B stacked on it and a region GB on organic layer 112G with organic layer 112B stacked on it can be formed.

[0160] Preferably, organic layers 112R, 112G, and 112B are not formed on the connecting electrode 111C.

[0161] Here, organic layer 112R, organic layer 112G, and organic layer 112B are formed in that order, but the formation order is not limited to this.

[0162] [Formation of organic layer 116] Next, organic layers 112R, 112G, and 112B are applied to form organic layer 116 (Figure 9C). Organic layer 116 can be formed in the same way as organic layer 115.

[0163] [Formation of sacrificial membrane 144] Next, an organic layer 116 is applied to form a sacrificial membrane 144.

[0164] The sacrificial film 144 can be a film with high resistance to etching of organic layers 115, 112, and 116, i.e., a film with a high etch selectivity. Furthermore, the sacrificial film 144 can be a film with a high etch selectivity compared to sacrificial films such as sacrificial film 146 described later. Moreover, the sacrificial film 144 is particularly preferably a film that can be removed by a wet etching method that causes minimal damage to organic layers 115, 112, and 116.

[0165] As the sacrificial film 144, inorganic films such as metal films, alloy films, metal oxide films, semiconductor films, and inorganic insulating films can be appropriately used. The sacrificial film 144 is formed by various deposition methods such as sputtering, evaporation, CVD, and ALD.

[0166] In particular, since the ALD method causes little damage to the deposited layer, the sacrificial film 144 formed directly on the organic layer 116 is preferably formed using the ALD method.

[0167] As the sacrificial film 144, for example, metallic materials such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, titanium, aluminum, yttrium, zirconium, and tantalum, or alloys containing such metallic materials, can be used. Low-melting-point materials such as aluminum or silver are particularly preferred.

[0168] Alternatively, metal oxides such as indium gallium zinc oxide (In-Ga-Zn oxide, also denoted as IGZO) can be used as the sacrificial film 144. Furthermore, indium oxide, indium zinc oxide (In-Zn oxide), indium tin oxide (In-Sn oxide), indium titanium oxide (In-Ti oxide), indium tin zinc oxide (In-Sn-Zn oxide), indium titanium zinc oxide (In-Ti-Zn oxide), and indium gallium tin zinc oxide (In-Ga-Sn-Zn oxide) can be used. Alternatively, silicon-containing indium tin oxide can also be used.

[0169] Note that this can also be applied to cases where element M (which is one or more of aluminum, silicon, boron, yttrium, tin, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, and magnesium) is used instead of gallium. In particular, M is preferably one or more of gallium, aluminum, and yttrium.

[0170] Furthermore, the sacrificial film 144 can be made of oxides such as alumina, hafnium oxide, and silicon oxide, nitrides such as silicon nitride and aluminum nitride, or oxynitrides such as silicon oxynitride. Such inorganic insulating materials can be formed using deposition methods such as sputtering, CVD, or ALD.

[0171] As the sacrificial film 144, a material soluble in a solvent that is chemically stable to at least the uppermost organic layer 116 of the EL layer can also be used. In particular, a material soluble in water or alcohol can be suitably used for the sacrificial film 144. When depositing the sacrificial film 144, it is preferable to coat the sacrificial film 144 by a wet deposition method in a solvent such as water or alcohol, and then perform a heat treatment to evaporate the solvent. At this time, it is preferable to perform the heat treatment under a reduced pressure atmosphere, thereby removing the solvent at a low temperature and for a short time, and reducing thermal damage to the EL layer.

[0172] Wet deposition methods used to form the sacrificial film 144 include spin coating, dip coating, spray coating, inkjet coating, dispenser coating, screen printing, flatbed printing, doctor knife coating, slot coating, roller coating, curtain coating, and doctor blade coating.

[0173] As the sacrificial membrane 144, organic materials such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinylpyrrolidone, polyethylene glycol, polyglycerol, pullulan, water-soluble cellulose, or alcohol-soluble polyamide resin can be used.

[0174] [Formation of sacrificial membrane 146] Next, a sacrificial membrane 146 is formed on the sacrificial membrane 144.

[0175] The sacrificial film 146 is used as a hard mask during subsequent etching of the sacrificial film 144. Furthermore, the sacrificial film 144 is exposed during the subsequent processing of the sacrificial film 146. Therefore, a combination of films with a greater etching selectivity is selected between the sacrificial films 144 and 146. Thus, the film suitable for use as the sacrificial film 146 can be selected based on the etching conditions of both the sacrificial film 144 and the sacrificial film 146.

[0176] The sacrificial film 146 can be selected from various materials depending on the etching conditions of the sacrificial film 144 and the sacrificial film 146. For example, it can be selected from films that can be used in the sacrificial film 144 described above.

[0177] For example, an oxide film can be used as the sacrificial film 146. Typically, oxide films or oxynitride films such as silicon oxide, silicon oxynitride, aluminum oxide, aluminum oxynitride, hafnium oxide, and hafnium oxynitride can also be used.

[0178] Additionally, a nitride film can be used as the sacrificial film 146, for example. Specifically, silicon nitride, aluminum nitride, hafnium nitride, titanium nitride, tantalum nitride, tungsten nitride, gallium nitride, germanium nitride, and other nitrides can be used.

[0179] For example, preferably, inorganic insulating materials such as alumina, hafnium oxide, and silicon oxide formed by the ALD method are used as sacrificial film 144, and indium-containing metal oxides such as indium gallium zinc oxide (also referred to as In-Ga-Zn oxide or IGZO) formed by sputtering are used as sacrificial film 146. Alternatively, metals such as tungsten, molybdenum, copper, aluminum, titanium, and tantalum, or alloys containing such metals, are preferably used as sacrificial film 146.

[0180] Alternatively, an organic film suitable for organic layers 115, 112, and 116 can be used as the sacrificial film 146. For example, the same organic film used for organic layers 115, 112, or 116 can be used as the sacrificial film 146. By using such an organic film, the deposition apparatus can be used together with organic layers 115, 112, and 116, which is preferable. Furthermore, when the subsequent sacrificial layer 147 is used as a mask to etch organic layers 115, 112, and 116, the sacrificial layer 147 can be removed simultaneously, thus simplifying the process.

[0181] [Formation of the light-blocking mask 143] Next, photoresist masks 143 are formed on the sacrificial film 146 at positions that overlap with pixel electrode 111R, pixel electrode 111G and pixel electrode 111B (Fig. 10A).

[0182] The photoresist mask 143 can be a photoresist material containing a photosensitive resin, such as a positive photoresist material or a negative photoresist material.

[0183] Here, when a photoresist mask 143 is formed on a sacrificial film 144 without the sacrificial film 146, if there are defects such as pinholes in the sacrificial film 144, the organic layers 115, 112, and 116 may dissolve due to the solvent of the photoresist material. By using the sacrificial film 146, this defect can be prevented.

[0184] Note that, in cases where the solvent used as the photoresist material is a material that does not dissolve organic layers 115, 112, and 116, a photoresist mask 143 may sometimes be formed directly on the sacrificial film 144 without using the sacrificial film 146.

[0185] [Etching of sacrificial film 146] Next, a strip-shaped sacrificial layer 147 is formed by etching away a portion of the sacrificial film 146 that is not covered by the photoresist mask 143.

[0186] When etching the sacrificial film 146, it is preferable to use etching conditions with a high selectivity to prevent the sacrificial film 144 from being removed by the etching. The etching of the sacrificial film 146 can be performed by wet etching or dry etching, but by using dry etching, the pattern shrinkage of the sacrificial layer 147 can be suppressed.

[0187] [Removal of photoresist mask 143] Next, remove the light-blocking mask 143.

[0188] The photoresist mask 143 can be removed using wet etching or dry etching. It is particularly preferred to remove the photoresist mask 143 using dry etching (also known as plasma ashing) that uses oxygen gas as the etching gas.

[0189] At this time, since the removal of the photoresist mask 143 is performed while the organic layer 116 is covered by the sacrificial film 144, the effects on the organic layers 115, 112, and 116 are suppressed. In particular, when the organic layers 115, 112, and 116 are exposed to oxygen, it can sometimes negatively affect their electrical properties, so this is preferable when performing etching using oxygen gases such as plasma ashing. Furthermore, when removing the photoresist mask 143 by wet etching, the organic layers 116 are not exposed to the chemical solution, thus preventing the organic layers 116 from dissolving.

[0190] [Etching of sacrificial film 144] Next, the sacrificial layer 147 is used as a hard mask and a portion of the sacrificial film 144 is removed by etching to form the sacrificial layer 145 (Fig. 10B).

[0191] The etching of the sacrificial film 144 can be performed using wet etching or dry etching, but dry etching is preferred, thereby suppressing pattern shrinkage.

[0192] [Etching of organic layers 116, 112, and 115] Next, a portion of the organic layers 116, 112, and 115 that are not sacrificed by the layer 145 are removed by etching to form the slit 120. At the same time, the top surface of the connecting electrode 111C is also exposed.

[0193] At this time, by etching a portion of organic layer 112R, organic layer 112G and organic layer 112B, layer 135R of fragments of organic layer 112R, layer 135G of fragments of organic layer 112G and layer 135B of fragments of organic layer 112B are formed.

[0194] In particular, the etching of organic layers 116, 112, and 115 is preferably performed using dry etching with an etching gas whose main component does not contain oxygen. This suppresses the deterioration of organic layers 116, 112, and 115, resulting in a display device with high reliability. Examples of etching gases whose main component does not contain oxygen include CF4, C4F8, SF6, CHF3, Cl2, H2O, BCl3, H2, or rare gases (He, etc.). Alternatively, a mixture of the above gases and an oxygen-free diluent gas can be used as the etching gas.

[0195] Note that the etching of organic layers 116, 112, and 115 is not limited to the methods described above. It can be performed using dry etching with other gases or wet etching.

[0196] Furthermore, when etching organic layers 116, 112, and 115 using an etching gas containing oxygen or dry etching with oxygen, the etching rate can be increased. This allows etching to be performed at low power while maintaining a sufficient etching rate, thus reducing etching-related damage. Additionally, defects such as the adhesion of reaction products during etching can be suppressed. For example, an etching gas in which oxygen is added to an etching gas whose main components do not contain oxygen can be used.

[0197] When organic layers 116, 112, and 115 are etched, insulating layer 105 is exposed. Therefore, it is preferable to use a film with high resistance to etching of organic layer 115 as insulating layer 105. Note that during etching of organic layer 115, sometimes the top of insulating layer 105 is etched and not partially thinned by organic layer 115.

[0198] Alternatively, the sacrificial layer 147 can be etched simultaneously with the etching of organic layers 116, 112, and 115. By etching organic layers 116, 112, 115, and 147 in the same process, the manufacturing process can be simplified, and the manufacturing cost of the display device can be reduced, which is therefore preferable.

[0199] [Removal of the sacrificial layer] Next, the sacrificial layer 147 is removed, exposing the top surface of the sacrificial layer 145 (Fig. 10C). At this point, the sacrificial layer 145 is preferably remaining. Alternatively, the sacrificial layer 147 may not be removed at this point.

[0200] [Formation of insulating film 125f] Next, an insulating film 125f is deposited over the sacrificial layer 145 and the slit 120.

[0201] The insulating film 125f is used as a barrier layer to prevent impurities such as water from diffusing into the EL layer. Preferably, the insulating film 125f is formed using the ALD method, which has excellent step coverage, thereby appropriately covering the sides of the EL layer.

[0202] The insulating film 125f is preferably made of the same material as the sacrificial layer 145, so that etching can be performed simultaneously in subsequent processes. For example, it is preferable to use inorganic insulating materials such as alumina, hafnium oxide, and silicon oxide formed by the ALD method for both the insulating film 125f and the sacrificial layer 145.

[0203] Note that the materials that can be used for insulating film 125f are not limited to this, and materials that can be used for the sacrificial film 144 described above can be used appropriately.

[0204] [Formation of resin layer 126] Next, a resin layer 126 (FIG. 11A) is formed in the region overlapping the slit 120. The resin layer 126 can be formed in the same way as the resin layer 163.

[0205] Here, an example is shown where the resin layer 126 is formed with its width greater than the width of the slit 120.

[0206] [Etching of insulating film 125f and sacrificial layer 145] Next, the portions of the insulating film 125f and the sacrificial layer 145 not covered by the resin layer 126 are removed by etching, exposing the top surface of the organic layer 116. At this time, the insulating layer 125 and the sacrificial layer 145 are simultaneously formed in the area covered by the resin layer 126 (Fig. 11B).

[0207] Preferably, the insulating film 125f and the sacrificial layer 145 are etched using the same process. In particular, the etching of the sacrificial layer 145 is preferably performed by wet etching, which causes less etch damage to the organic layer 116. For example, it is preferable to use wet etching with an aqueous solution of tetramethylammonium hydroxide (TMAH), dilute hydrofluoric acid, oxalic acid, phosphoric acid, acetic acid, nitric acid, or a mixture thereof.

[0208] Alternatively, it is preferable to remove either or both of the insulating film 125f and the sacrificial layer 145 by dissolving them in a solvent such as water or alcohol. Here, various alcohols such as ethanol, methanol, isopropanol (IPA), or glycerol can be used as the alcohol that can dissolve the insulating film 125f and the sacrificial layer 145.

[0209] To remove water contained within organic layers 115, 112, and 116, and water adsorbed on the surface, after removing the insulating film 125f and the sacrificial layer 145, a drying process is preferably performed. For example, heating is preferably performed under an inert gas atmosphere or a reduced-pressure atmosphere. During the heating process, the substrate temperature can be above 50°C and below 200°C, preferably above 60°C and below 150°C, and more preferably above 70°C and below 120°C. Using a reduced-pressure atmosphere allows for drying at a lower temperature, which is therefore preferable.

[0210] [Formation of organic layer 114] Next, an organic layer 114 is deposited, including an organic layer 116, an insulating layer 125, a sacrificial layer 145, and a resin layer 126.

[0211] Organic layer 114 can be deposited using the same method as organic layer 115. When depositing organic layer 114 using vapor deposition, shadow masking can also be used to prevent organic layer 114 from being deposited on the connecting electrode 111C.

[0212] [Formation of common electrode 113] Next, a common electrode 113 is formed by covering it with an organic layer 114.

[0213] The common electrode 113 can be formed by deposition methods such as vapor deposition or sputtering. Alternatively, a film formed by vapor deposition and a film formed by sputtering can be stacked.

[0214] The common electrode 113 is preferably formed in a manner that includes a region containing the deposited organic layer 114. That is, the end of the organic layer 114 may overlap with the common electrode 113. The common electrode 113 may also be formed using a shadow mask.

[0215] In the connection portion 130, an organic layer 114 is sandwiched between the connecting electrode 111C and the common electrode 113. Preferably, the organic layer 114 is made of a material with the lowest possible resistance. Alternatively, by forming it as thin as possible, it is preferable to reduce the resistance in the thickness direction of the organic layer 114. For example, by using an electron-injecting or hole-injecting material with a thickness of 1 nm or more and 5 nm or less, preferably 1 nm or more and 3 nm or less, as the organic layer 114, the resistance between the connecting electrode 111C and the common electrode 113 can sometimes be reduced to a negligible level.

[0216] [Formation of the protective layer] Next, a protective layer 121 is formed on the common electrode 113 (FIG. 11C). When depositing the inorganic insulating film for the protective layer 121, sputtering, PECVD, or ALD methods are preferred. In particular, ALD is preferred because it provides good step coverage and is less prone to defects such as pinholes. Alternatively, when depositing the organic insulating film, inkjet printing is preferred because it allows for uniform film formation in the desired area.

[0217] The display device shown in Figure 7A can be manufactured using the above process.

[0218] Note that the above example shows the resin layer 126 being formed with its width greater than the width of the slit 120, but the resin layer 126 may also be formed with its width matching the width of the slit 120.

[0219] Figure 12A is a cross-sectional view of the resin layer 126 formed after the insulating film 125f is formed.

[0220] For example, as shown in FIG12A, by forming a resin layer 126 whose width is greater than that of the slit 120 and then etching the top of the resin layer 126 using ashing or the like, the resin layer 126 can be formed only inside the slit 120. In this case, it is preferable to make the height of the top surface of the resin layer 126 as consistent as possible with the height of the top surface of the adjacent organic layer 116. This reduces the number of steps originating from the slit 120 and improves the step coverage of the organic layer 114, etc.

[0221] Next, the insulating film 125f and the sacrificial layer 145 are etched in the same manner as described above (Fig. 12B). At this time, because the portion of the sacrificial layer 145 not covered by the resin layer 126 is not covered, the sacrificial layer 145 is removed without leaving any fragments.

[0222] Next, by forming the organic layer 114, the common electrode 113, and the protective layer 121 in the same manner as described above, the display device can be manufactured as shown in FIG12C.

[0223] Additionally, Figure 12C shows an example where the organic layer 114 is not provided between the connecting electrode 111C and the common electrode 113. Because the connecting electrode 111C is in contact with the common electrode 113, the contact resistance between them can be minimized, thereby reducing power consumption.

[0224] The above is an explanation of an example of a manufacturing method for a display device.

[0225] At least a portion of this embodiment can be implemented in combination with other embodiments described in this specification.

[0226] Implementation Method 2 In this embodiment, an example of the structure of a display device according to one embodiment of the present invention is described.

[0227] The display device in this embodiment can be a high-resolution display device or a large-screen display device. Therefore, the display device in this embodiment can be used, for example, as a display unit for devices such as: electronic devices with large screens, such as televisions, desktop or laptop computers, monitors for computers, digital signage, large game consoles such as pinball machines, etc.; digital cameras; digital video cameras; digital photo frames; mobile phones; portable game consoles; smartphones; watch-type terminals; tablet terminals; portable information terminals; and audio playback devices.

[0228] [Light-emitting device 400] Figure 13 shows a perspective view of the light-emitting device 400, and Figure 14A shows a cross-sectional view of the light-emitting device 400.

[0229] The display device 400 has a structure that attaches substrate 452 and substrate 451. In FIG13, substrate 452 is indicated by dashed lines.

[0230] The display device 400 includes a display unit 462, circuitry 464, and wiring 465, etc. Figure 13 shows an example in which an IC 473 and an FPC 472 are installed in the display device 400. Therefore, the structure shown in Figure 13 can also be referred to as a display module including the display device 400, the IC (integrated circuit), and the FPC.

[0231] For example, a scan line drive circuit can be used as circuit 464.

[0232] Wiring 465 has the function of supplying signals and power to display unit 462 and circuit 464. The signals and power are input to wiring 465 from the outside via FPC 472 or IC 473.

[0233] Figure 13 shows an example of IC 473 being mounted on substrate 451 using COG (Chip On Glass) or COF (Chip On Film) methods. IC 473 can be, for example, an IC including scan line drive circuitry or signal line drive circuitry. Note that the display device 400 and display module do not necessarily need to have an IC mounted on them. Alternatively, the IC can be mounted on an FPC using COF or similar methods.

[0234] Figure 14A shows an example of a cross-section of a portion of the display device 400 including the FPC 472, a portion of the circuit 464, a portion of the display section 462, and a portion of the region including the connection section. Figure 14A particularly shows an example of a cross-section of the region of the display section 462 including the light-emitting element 430b emitting green light and the light-emitting element 430c emitting blue light.

[0235] The display device 400 shown in Figure 14A includes transistors 202 and 210, light-emitting elements 430b and 430c, etc., between substrates 453 and 454.

[0236] The light-emitting elements 430b and 430c can be the light-emitting elements illustrated in Embodiment 1.

[0237] Here, when a pixel of a display device includes three sub-pixels having light-emitting elements that emit light differently from each other, examples of these three sub-pixels include sub-pixels of three colors: red (R), green (G), and blue (B), and sub-pixels of three colors: yellow (Y), cyan (C), and magenta (M). When four of the above-mentioned sub-pixels are included, examples of these four sub-pixels include sub-pixels of four colors: R, G, B, and white (W), and sub-pixels of four colors: R, G, B, and Y.

[0238] Furthermore, the substrate 454 and the protective layer 416 are bonded together by the adhesive layer 442. The adhesive layer 442 overlaps with the light-emitting elements 430b and 430c respectively, and the display device 400 adopts a solid sealing structure.

[0239] Light-emitting elements 430b and 430c, serving as pixel electrodes, include conductive layers 411a, 411b, and 411c. Conductive layer 411b is reflective of visible light and is used as a reflective electrode. Conductive layer 411c is transmissive of visible light and is used as an optical adjustment layer.

[0240] The conductive layer 411a is electrically connected to the conductive layer 222b included in the transistor 210 through an opening provided in the insulating layer 214. The transistor 210 has the function of controlling the driving of the light-emitting element.

[0241] An EL layer 412G or EL layer 412B is provided over the pixel electrode. An insulating layer 421 is provided in contact with the side surfaces of EL layer 412G and EL layer 412B, and a resin layer 422 is provided to fill the recesses of the insulating layer 421. An organic layer 414, a common electrode 413, and a protective layer 416 are provided over EL layers 412G and EL layer 412B. In addition, layers 415B and 415G are provided in contact with the insulating layer 421. Layer 415B contains the same material as EL layer 412B, and layer 415G contains the same material as EL layer 412G.

[0242] The light-emitting element emits light onto one side of the substrate 452. The substrate 452 is preferably made of a material with high transmittance to visible light.

[0243] Transistor 202 and transistor 210 are both disposed on substrate 451. These transistors can be formed using the same material and the same process.

[0244] The substrate 453 and the insulating layer 212 are bonded together by the adhesive layer 455.

[0245] The manufacturing method of the display device 400 is as follows: First, a manufacturing substrate having an insulating layer 212, transistors, light-emitting devices, etc., disposed on it is bonded together with a substrate 454 having a light-shielding layer 417 using an adhesive layer 442; then, the manufacturing substrate is peeled off and bonded to the exposed substrate 453 to transfer the components formed on the manufacturing substrate to the substrate 453. The substrates 453 and 454 are preferably flexible. This improves the flexibility of the display device 400.

[0246] As insulating layer 212, an inorganic insulating film that can be used for insulating layers 211 and 215 can be used.

[0247] A connection portion 204 is provided in a region of substrate 453 that does not overlap with substrate 454. In the connection portion 204, wiring 465 is electrically connected to FPC 472 via conductive layer 466 and connection layer 242. Conductive layer 466 can be obtained by processing a conductive film identical to that of the pixel electrode. Therefore, the connection portion 204 can be electrically connected to FPC 472 via connection layer 242.

[0248] Transistors 202 and 210 include: a conductive layer 221 serving as a gate; an insulating layer 211 serving as a gate insulating layer; a semiconductor layer 231 including a channel forming region 231i and a pair of low-resistance regions 231n; a conductive layer 222a connected to one of the pair of low-resistance regions 231n; a conductive layer 222b connected to the other of the pair of low-resistance regions 231n; an insulating layer 225 serving as a gate insulating layer; a conductive layer 223 serving as a gate; and an insulating layer 215 covering the conductive layer 223. The insulating layer 211 is located between the conductive layer 221 and the channel forming region 231i. The insulating layer 225 is located between the conductive layer 223 and the channel forming region 231i.

[0249] Conductive layers 222a and 222b are connected to the low-resistance region 231n through openings provided in the insulating layer 215. One of the conductive layers 222a and 222b serves as a source, and the other serves as a drain.

[0250] Figure 14A shows an example of insulating layer 225 covering the top and side surfaces of semiconductor layer. Conductive layers 222a and 222b are connected to low-resistance region 231n through openings provided in insulating layers 225 and 215.

[0251] On the other hand, in the transistor 209 shown in FIG14B, the insulating layer 225 overlaps with the channel forming region 231i of the semiconductor layer 231 but does not overlap with the low-resistance region 231n. For example, the structure shown in FIG14B can be formed by processing the insulating layer 225 with the conductive layer 223 as a mask. In FIG14B, the insulating layer 215 covers the insulating layer 225 and the conductive layer 223, and the conductive layers 222a and 222b are respectively connected to the low-resistance region 231n through the opening of the insulating layer 215. Furthermore, an insulating layer 218 covering the transistor may also be provided.

[0252] There are no particular limitations on the transistor structure included in the display device of this embodiment. For example, planar transistors, interleaved transistors, or anti-interleaved transistors can be used. Furthermore, the transistors can have a top-gate structure or a bottom-gate structure. Alternatively, gates can be provided above and below the semiconductor layer forming the channel.

[0253] Transistors 202 and 210 employ a structure in which a semiconductor layer forming a channel is sandwiched between two gates. Alternatively, the two gates can be connected, and the transistor can be driven by supplying the same signal to both gates. Or, the threshold voltage of the transistor can be controlled by applying a potential to one of the two gates to control the threshold voltage and applying a potential to the other to drive it.

[0254] There are no particular restrictions on the crystallinity of the semiconductor material used for the semiconductor layer of the transistor; amorphous semiconductors, single-crystal semiconductors, or crystalline semiconductors other than single-crystal semiconductors (microcrystalline semiconductors, polycrystalline semiconductors, or semiconductors with crystalline regions in some of them) can be used. When using single-crystal semiconductors or crystalline semiconductors, the degradation of transistor characteristics can be suppressed, so it is preferable.

[0255] The semiconductor layer of the transistor is preferably made of metal oxide (oxide semiconductor). That is, the display device of this embodiment preferably uses a transistor (hereinafter, OS transistor) that contains metal oxide in the channel forming region.

[0256] The band gap of the metal oxide used in the semiconductor layer of the transistor is preferably 2 eV or higher, and more preferably 2.5 eV or higher. By using a metal oxide with a wider band gap, the off-state current of the OS transistor can be reduced.

[0257] The metal oxide preferably contains at least indium or zinc, and more preferably contains both indium and zinc. For example, the metal oxide preferably contains indium, M (M is selected from one or more of gallium, aluminum, yttrium, tin, silicon, boron, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, magnesium, and cobalt), and zinc. In particular, M is preferably selected from one or more of gallium, aluminum, yttrium, and tin, and more preferably gallium. Note that the metal oxide containing indium, M, and zinc is sometimes referred to below as an In-M-Zn oxide.

[0258] When using In-M-Zn oxide in metal oxides, the number of In atoms in the In-M-Zn oxide is preferably greater than or equal to the number of M atoms. Examples of atomic ratios of the metal elements in this In-M-Zn oxide include In:M:Zn = 1:1:1 or similar, In:M:Zn = 1:1:1.2 or similar, In:M:Zn = 2:1:3 or similar, In:M:Zn = 3:1:2 or similar, In:M:Zn = 4:2:3 or similar, In:M:Zn = 4:2:4.1 or similar, In:M:Zn = 5:1:3 or similar, In:M:Zn = 5:1:6 or similar, In:M:Zn = 5:1:7 or similar, In:M:Zn = 5:1:8 or similar, In:M:Zn = 6:1:6 or similar, In:M:Zn = 5:2:5 or similar, etc. Furthermore, "similar" composition includes a range of ±30% of the desired atomic ratio. By increasing the atomic ratio of indium in metal oxides, the on-state current or field-effect mobility of transistors can be improved.

[0259] For example, when the atomic number ratio is described as In:Ga:Zn = 4:2:3 or similar, the following cases are included: when the atomic number ratio of In is 4, the atomic number ratio of Ga is 1 or more and 3 or less, and the atomic number ratio of Zn is 2 or more and 4 or less. Furthermore, when the atomic number ratio is described as In:Ga:Zn = 5:1:6 or similar, the following cases are included: when the atomic number ratio of In is 5, the atomic number ratio of Ga is greater than 0.1 and less than 2, and the atomic number ratio of Zn is 5 or more and less than 7. Furthermore, when the atomic number ratio is described as In:Ga:Zn = 1:1:1 or similar, the following cases are included: when the atomic number ratio of In is 1, the atomic number ratio of Ga is greater than 0.1 and less than 2, and the atomic number ratio of Zn is greater than 0.1 and less than 2.

[0260] The atomic ratio of In in In-M-Zn oxides can also be less than the atomic ratio of M. Examples of such metallic atomic ratios in In-M-Zn oxides include In:M:Zn = 1:3:2 or similar, In:M:Zn = 1:3:3 or similar, In:M:Zn = 1:3:4 or similar, etc. By increasing the atomic ratio of M in the metal oxide, the band gap of the In-M-Zn oxide can be widened, thereby improving its resistance to optical negative bias stress testing. Specifically, this can reduce the change in critical voltage or drift voltage (Vsh) measured in the NBTIS (Negative Bias Temperature Illumination Stress) test of the transistor. Note that the drift voltage (Vsh) is defined as Vg at the intersection of the tangent line at the point where the slope of the transistor's drain current (Id) - gate voltage (Vg) curve is greatest and the straight line at Id = 1 pA.

[0261] Alternatively, the semiconductor layer of the transistor can also contain silicon. Examples of silicon include amorphous silicon and crystalline silicon (low-temperature polycrystalline silicon, monocrystalline silicon, etc.).

[0262] Alternatively, the semiconductor layer of a transistor can also have a layered material that serves as the semiconductor. Layered materials are a general term for a group of materials with a layered crystalline structure. A layered crystalline structure is a structure formed by layers of covalent or ionic bonds stacked together by bonds weaker than covalent or ionic bonds, such as van der Waals forces. Layered materials exhibit high conductivity per unit layer, that is, high two-dimensional conductivity. By using a material with high two-dimensional conductivity that serves as the semiconductor in the channel-forming region, transistors with high on-state current can be provided.

[0263] Examples of the aforementioned layered materials include graphene, silicon, and chalcogenides. Chalcogenides are compounds containing chalcogen elements (elements belonging to Group 16). Furthermore, examples of chalcogenides include transition metal chalcogenides and Group 13 chalcogenides. Specific examples of transition metal chalcogenides that can be used as semiconductor layers in transistors include molybdenum sulfide (typically MoS₂), molybdenum selenide (typically MoSe₂), molybdenum telluride (typically MoTe₂), tungsten sulfide (typically WS₂), tungsten selenide (typically WSe₂), tungsten telluride (typically WTe₂), hafnium sulfide (typically HfS₂), hafnium selenide (typically HfSe₂), zirconium sulfide (typically ZrS₂), and zirconium selenide (typically ZrSe₂).

[0264] The transistors included in circuit 464 and the transistors included in display unit 462 can have the same structure or different structures. The multiple transistors included in circuit 464 can have the same structure or two or more different structures. Similarly, the multiple transistors included in display unit 462 can have the same structure or two or more different structures.

[0265] Preferably, at least one of the insulating layers covering the transistor is made of a material that does not readily diffuse impurities such as water and hydrogen. This allows the insulating layer to function as a barrier layer. By employing this structure, the diffusion of impurities from the outside into the transistor can be effectively suppressed, thereby improving the reliability of the display device.

[0266] Inorganic insulating films are preferably used as insulating layers 211, 212, 215, 218, and 225. Examples of inorganic insulating films include silicon nitride films, silicon oxynitride films, silicon oxide films, silicon oxynitride films, aluminum oxide films, and aluminum nitride films. Additionally, hafnium oxide films, yttrium oxide films, zirconium oxide films, gallium oxide films, tantalum oxide films, magnesium oxide films, lanthanum oxide films, cerium oxide films, and neodymium oxide films can also be used. Furthermore, two or more of the above-mentioned inorganic insulating films can be laminated.

[0267] Here, the barrier properties of organic insulating films are often lower than those of inorganic insulating films. Therefore, it is preferable that the organic insulating film includes an opening near the end of the display device 400. This can prevent impurities from entering the display device 400 through the organic insulating film from the end. Alternatively, the organic insulating film can be formed with its end located inside the end of the display device 400, so that the organic insulating film is not exposed at the end of the display device 400.

[0268] The insulating layer 214 used as the planarization layer is preferably an organic insulating film. Materials suitable for use as organic insulating films include, for example, acrylic resins, polyimide resins, epoxy resins, polyimide resins, polyimide-polyimide resins, silicone resins, benzocyclobutene resins, phenolic resins, and precursors of the above resins.

[0269] Preferably, a light-shielding layer 417 is provided on the surface of the substrate 454 on the substrate 453 side. Furthermore, various optical components can be disposed on the outer side of the substrate 454. As optical components, polarizing plates, retardation plates, light diffusion layers (diffusion films, etc.), anti-reflection layers, and condensing films can be used. In addition, an antistatic film that inhibits dust adhesion, a water-repellent film that is not easily soiled, a hard coating film that inhibits damage during use, and an impact-absorbing layer can also be disposed on the outer side of the substrate 454.

[0270] By forming a protective layer 416 covering the light-emitting element, impurities such as water can be prevented from entering the light-emitting element, thereby improving the reliability of the light-emitting element.

[0271] Figure 14A shows the connection portion 228. In the connection portion 228, the common electrode 413 is electrically connected to the wiring. Figure 14A shows an example where the wiring adopts the same stacked structure as the pixel electrode.

[0272] Substrates 453 and 454 can be made of materials such as glass, quartz, ceramic, sapphire, and resin. The substrate on the side from which light is emitted from the light-emitting element uses a material that allows light to pass through. By using a flexible material for substrates 453 and 454, the flexibility of the display device can be improved. A polarizing plate can be used as substrate 453 or substrate 454.

[0273] The following materials can be used as substrates 453 and 454: polyester resins such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN), polyacrylonitrile resins, acrylic resins, polyimide resins, polymethyl methacrylate resins, polycarbonate (PC) resins, polyether ether (PES) resins, polyamide resins (nylon, aromatic polyamides, etc.), polysiloxane resins, cycloolefin resins, polystyrene resins, polyamide-imide resins, polyurethane resins, polyvinyl chloride resins, polyvinylidene chloride resins, polypropylene resins, polytetrafluoroethylene (PTFE) resins, ABS resins, and cellulose nanofibers, etc. Alternatively, one or both of substrates 453 and 454 can be made of glass with a flexible thickness.

[0274] When a circular polarizer is superimposed on a display device, it is preferable to use a substrate with high optical isotropy as the substrate included in the display device. The substrate with high optical isotropy has lower birefringence (or, in other words, less birefringence).

[0275] The absolute value of the retardation value of a substrate with high optical isotropy is preferably below 30 nm, more preferably below 20 nm, and even more preferably below 10 nm.

[0276] Examples of films with high optical isotropy include cellulose triacetate (also known as TAC), cyclic olefin polymer (COP) films, cyclic olefin copolymer (COC) films, and acrylic films.

[0277] When a thin film is used as a substrate, the display panel may experience shape changes such as wrinkles due to water absorption by the film. Therefore, it is preferable to use a thin film with a low water absorption rate as the substrate. For example, it is preferable to use a thin film with a water absorption rate of 1% or less, more preferably a thin film with a water absorption rate of 0.1% or less, and even more preferably a thin film with a water absorption rate of 0.01% or less.

[0278] As the adhesive layer, various curing adhesives can be used, including UV-curing adhesives, reaction-curing adhesives, thermosetting adhesives, and anaerobic adhesives. Examples of these adhesives include epoxy resins, acrylic resins, silicone resins, phenolic resins, polyimide resins, PVC (polyvinyl chloride) resins, PVB (polyvinyl butyral) resins, and EVA (ethylene vinyl acetate) resins. In particular, materials with low moisture permeability, such as epoxy resins, are preferred. Two-component mixed resins can also be used. Furthermore, adhesive sheets can also be used.

[0279] As the connecting layer 242, anisotropic conductive film (ACF) or anisotropic conductive paste (ACP) can be used.

[0280] Materials that can be used as gates, sources, and drains of transistors, as well as conductive layers such as wiring and electrodes in display devices, include metals such as aluminum, titanium, chromium, nickel, copper, yttrium, zirconium, molybdenum, silver, tantalum, or tungsten, or alloys with the above metals as the main component. Single layers or stacks of films containing these materials can be used.

[0281] Furthermore, as a transparent conductive material, conductive oxides such as indium oxide, indium tin oxide, indium zinc oxide, zinc oxide, and gallium-containing zinc oxide, or graphene, can be used. Alternatively, metallic materials such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, or titanium, or alloys containing such metallic materials, can be used. Alternatively, nitrides of the metallic materials (e.g., titanium nitride) can also be used. Furthermore, when using metallic or alloy materials (or their nitrides), it is preferable to form them thin enough to be transparent. Furthermore, a multilayer film of the above materials can be used as a conductive layer. For example, using a multilayer film of an alloy of silver and magnesium with indium tin oxide is preferred as it improves conductivity. The above materials can also be used as conductive layers constituting various wirings and electrodes in a display device, and as conductive layers included in light-emitting elements (conductive layers used as pixel electrodes or common electrodes).

[0282] Examples of insulating materials that can be used in various insulating layers include resins such as acrylic resin or epoxy resin, and inorganic insulating materials such as silicon oxide, silicon oxynitride, silicon oxynitride, silicon nitride, or aluminum oxide.

[0283] At least a portion of the structural examples shown in this embodiment and the corresponding diagrams can be appropriately combined with other structural examples or diagrams.

[0284] At least a portion of this embodiment can be implemented in combination with other embodiments described in this specification.

[0285] Implementation Method 3 The following describes an example of the structure of pixels in the display section of a display device.

[0286] The display device 100 shown in Figure 1A is an example of a striped arrangement. In Figure 1A, the striped arrangement consists of three sub-pixels, R, G, and B. Sub-pixels R, G, and B each include a light-emitting device with a different emitting color. For example, sub-pixels R, G, and B can be red, green, and blue sub-pixels, respectively.

[0287] Pixel 103 shown in Figure 15A uses an S-shaped stripe arrangement. Pixel 103 shown in Figure 15A is composed of three sub-pixels: R, G, and B.

[0288] The pixel 103 shown in Figure 15B includes a sub-pixel G with a roughly trapezoidal top surface shape with rounded corners, a sub-pixel R with a roughly triangular top surface shape with rounded corners, and a sub-pixel B with a roughly quadrilateral or roughly hexagonal top surface shape with rounded corners. Furthermore, the light-emitting area of ​​sub-pixel G is larger than that of sub-pixel R. Thus, the shape and size of each sub-pixel can be determined independently. For example, the size of a sub-pixel including a highly reliable light-emitting device can be smaller. For example, sub-pixels R, G, and B can be red, green, and blue sub-pixels, respectively.

[0289] Pixels 125a and 125b shown in Figure 15C are arranged in a Pentile pattern. Figure 15C shows an example of pixel 125a, which includes sub-pixels R and G, and pixel 125b, which includes sub-pixels G and B, arranged alternately. For example, sub-pixels R, G, and B can be red, green, and blue sub-pixels, respectively.

[0290] Pixels 125a and 125b shown in Figures 15D and 15E are arranged in a Delta pattern. Pixel 125a includes two sub-pixels (sub-pixels R and G) in the upper row (first row) and one sub-pixel (sub-pixel B) in the lower row (second row). Pixel 125b includes one sub-pixel (sub-pixel B) in the upper row (first row) and two sub-pixels (sub-pixels R and G) in the lower row (second row).

[0291] Figure 15D is an example of a sub-pixel having an approximately quadrilateral top surface shape with rounded corners, and Figure 15E is an example of a sub-pixel having a circular top surface shape.

[0292] In photolithography, the finer the pattern being processed, the more significant the effect of light diffraction becomes. Therefore, when transferring the pattern from the photomask through exposure, its fidelity decreases, making it difficult to process the photomask into the desired shape. Consequently, even if the photomask pattern is rectangular, it is easy to form a pattern with rounded corners. Thus, the top surface shape of subpixels sometimes takes the form of a polygon with rounded corners, an ellipse, or a circle.

[0293] Furthermore, in a method for manufacturing a display device according to one embodiment of the present invention, the EL layer is processed into an island shape using a photoresist mask. The photoresist film formed on the EL layer needs to be cured at a temperature lower than the heat resistance temperature of the EL layer. Therefore, depending on the heat resistance temperature of the EL layer material and the curing temperature of the photoresist material, the photoresist film is sometimes not fully cured. The insufficiently cured photoresist film sometimes takes on a shape far from the desired shape during processing. As a result, the top surface shape of the EL layer is sometimes a polygonal shape with rounded corners, an ellipse, or a circle, etc. For example, when a photoresist mask with a square top surface shape is to be formed, sometimes a photoresist mask with a circular top surface shape is formed and the top surface shape of the EL layer is circular.

[0294] To ensure the top surface of the EL layer has the desired shape, a technique called OPC (Optical Proximity Correction) can be used to pre-correct the mask pattern in a way that aligns with the design pattern and the transfer pattern. Specifically, in OPC, correction patterns are added to the corners and other parts of the pattern on the mask pattern.

[0295] The pixels 103 shown in Figures 16A to 16C are arranged in a stripe pattern. Pixel 103 in Figures 16A to 16C consists of four sub-pixels: R, G, B, and W. Sub-pixels R, G, B, and W each include a light-emitting device with a different emitted color. For example, sub-pixels R, G, B, and W can be red, green, blue, and white sub-pixels, respectively.

[0296] Figure 16A shows an example where each sub-pixel has a rectangular top surface shape; Figure 16B shows an example where each sub-pixel has a top surface shape connecting two semicircles and a rectangle; and Figure 16C shows an example where each sub-pixel has an elliptical top surface shape.

[0297] The pixels 103 shown in Figures 16D to 16F are arranged in a matrix. The pixels 103 shown in Figures 16D to 16F are composed of four sub-pixels: R, G, B, and W.

[0298] Figure 16D shows an example where each sub-pixel has a square top surface shape; Figure 16E shows an example where each sub-pixel has an approximately square top surface shape with rounded corners; Figure 16F shows an example where each sub-pixel has a circular top surface shape. Figure 16G shows an example including sub-pixels R, G, and B arranged in a stripe pattern, and three sub-pixels W.

[0299] Implementation Method 4 In this embodiment, a light-emitting element (also called a light-emitting device) of a display device that can be used in one embodiment of the present invention will be described.

[0300] In this specification, etc., devices manufactured using a metal mask or FMM (Fine Metal Mask) are sometimes referred to as devices having an MM (Metal Mask) structure. Furthermore, in this specification, etc., devices manufactured without a metal mask or FMM are sometimes referred to as devices having an MML (Metal Mask Less) structure.

[0301] Furthermore, in this specification, the structure in which light-emitting devices of each color (here, blue (B), green (G), and red (R)) are separately formed or coated with light-emitting layers is sometimes referred to as an SBS (Side By Side) structure. Additionally, in this specification, a light-emitting device capable of emitting white light is sometimes referred to as a white light-emitting device. A white light-emitting device, combined with a color layer (e.g., a color filter), can realize a full-color display device.

[0302] Furthermore, light-emitting devices can be broadly categorized into single-structure and series-structure devices. A preferred single-structure device has the following structure: a light-emitting unit is included between a pair of electrodes, and this light-emitting unit includes one or more light-emitting layers. To achieve white light emission with a single structure, the light-emitting layers are selected such that their emission colors are complementary. For example, by making the emission colors of the first and second light-emitting layers complementary, a structure in which the entire light-emitting device emits white light can be obtained. The same applies to light-emitting devices comprising three or more light-emitting layers.

[0303] A preferred structure for a series-connected device is one comprising two or more light-emitting units between a pair of electrodes, and each light-emitting unit comprising one or more light-emitting layers. By using light-emitting layers that emit light of the same color in each light-emitting unit, a light-emitting device with increased brightness per specified current and higher reliability than a single-structure device can be achieved. To obtain white light emission in a series-connected structure, a structure is used to combine the light emitted from the light-emitting layers of multiple light-emitting units to obtain white light emission. Note that the combination of light emission colors to obtain white light emission is the same as in a single-structure device. Furthermore, in a series-connected device, it is preferable to provide an intermediate layer such as a charge-generating layer between the multiple light-emitting units.

[0304] Furthermore, when comparing the aforementioned white light-emitting devices (single-structure or series-structure) and SBS structure light-emitting devices, the SBS structure light-emitting device exhibits lower power consumption than the white light-emitting device. Therefore, the SBS structure light-emitting device is preferable when power consumption reduction is desired. On the other hand, the manufacturing process for white light-emitting devices is simpler than that for SBS structure light-emitting devices, thereby reducing manufacturing costs or increasing manufacturing yield, making it a better choice.

[0305] <Examples of light-emitting device structures> As shown in Figure 17A, the light-emitting device includes an EL layer 786 between a pair of electrodes (lower electrode 772 and upper electrode 788). The EL layer 786 may be composed of multiple layers such as layer 4420, light-emitting layer 4411, and layer 4430. Layer 4420 may include, for example, a layer containing a substance with high electron injection capability (electron injection layer) and a layer containing a substance with high electron transport capability (electron transport layer). Light-emitting layer 4411 may, for example, contain a light-emitting compound. Layer 4430 may, for example, include a layer containing a substance with high hole injection capability (hole injection layer) and a layer containing a substance with high hole transport capability (hole transport layer).

[0306] The structure including layer 4420, light-emitting layer 4411 and layer 4430 disposed between a pair of electrodes can be used as a single light-emitting unit. In this specification, the structure of FIG17A is referred to as a single structure.

[0307] Figure 17B shows a modified example of the EL layer 786 included in the light-emitting device shown in Figure 17A. Specifically, the light-emitting device shown in Figure 17B includes layer 4430-1 on the lower electrode 772, layer 4430-2 on layer 4430-1, light-emitting layer 4411 on layer 4430-2, layer 4420-1 on light-emitting layer 4411, layer 4420-2 on layer 4420-1, and upper electrode 788 on layer 4420-2. For example, when the lower electrode 772 is used as the anode and the upper electrode 788 is used as the cathode, layer 4430-1 is used as the hole injection layer, layer 4430-2 is used as the hole transport layer, layer 4420-1 is used as the electron transport layer, and layer 4420-2 is used as the electron injection layer. Alternatively, when the lower electrode 772 is used as the cathode and the upper electrode 788 is used as the anode, layer 4430-1 is used as the electron injection layer, layer 4430-2 is used as the electron transport layer, layer 4420-1 is used as the hole transport layer, and layer 4420-2 is used as the hole injection layer. By employing the above layer structure, carriers can be efficiently injected into the light-emitting layer 4411, thereby improving the recombination efficiency of carriers within the light-emitting layer 4411.

[0308] Furthermore, as shown in Figures 17C and 17D, the structure with multiple light-emitting layers (light-emitting layers 4411, 4412, and 4413) disposed between layer 4420 and layer 4430 is also a variation of the single structure.

[0309] As shown in Figures 17E and 17F, the structure in which multiple light-emitting units (EL layers 786a and 786b) are connected in series with an intermediate layer (charge generation layer) 4440 is referred to as a series structure in this specification. While the structure shown in Figures 17E and 17F is referred to as a series structure in this specification, it is not limited to this; for example, a series structure may also be referred to as a stacked structure. By employing a series structure, a light-emitting device capable of emitting light with high brightness can be realized.

[0310] In Figure 17C, light-emitting layers 4411, 4412, and 4413 that emit light of the same color can also be used.

[0311] Alternatively, different luminescent materials can be used for luminescent layers 4411, 4412, and 4413. When the light emitted by each of luminescent layer 4411, 4412, and 4413 is in a complementary color relationship, white light emission can be obtained. Figure 17D shows an example of a color layer 785 used as a color filter. By allowing white light to pass through the color filter, light of the desired color can be obtained.

[0312] Alternatively, in Figure 17E, the same luminescent material can be used for both luminescent layers 4411 and 4412. Or, luminescent materials emitting different colors of light can be used for both luminescent layers 4411 and 4412. When the light emitted by luminescent layer 4411 and the light emitted by luminescent layer 4412 are complementary colors, white light emission can be obtained. Figure 17F shows an example where a color layer 785 is also provided.

[0313] Note that in Figures 17C, 17D, 17E and 17F, as shown in Figure 17B, layers 4420 and 4430 can also have a stacked structure consisting of two or more layers.

[0314] The structure in which light-emitting layers (blue (B), green (G) and red (R)) are formed separately for each light-emitting device is called an SBS (Side By Side) structure.

[0315] The color of light emitted by the light-emitting device can be red, green, blue, cyan, magenta, yellow, or white, depending on the material constituting the EL layer 786. Furthermore, when the light-emitting device has a microcavity structure, the color purity can be further improved.

[0316] White light-emitting devices preferably have a structure in which the light-emitting layer contains two or more light-emitting materials. To obtain white light emission, two or more light-emitting materials whose light emission is in a complementary color relationship can be selected. For example, by making the light emission color of the first light-emitting layer complementary to the light emission color of the second light-emitting layer, a light-emitting device that emits white light throughout the device can be obtained. Furthermore, the same applies to light-emitting devices that include three or more light-emitting layers.

[0317] The luminescent layer preferably comprises two or more luminescent materials, each exhibiting the spectral characteristics of R (red), G (green), B (blue), Y (yellow), and O (orange). Alternatively, it preferably comprises two or more luminescent materials, each exhibiting the spectral characteristics of R, G, and B.

[0318] Here, we illustrate a specific structural example of a light-emitting device.

[0319] A light-emitting device includes at least a light-emitting layer. In addition, as a layer other than the light-emitting layer, the light-emitting device may also include a layer containing a material with high hole injection capacity, a material with high hole transport capacity, a hole blocking material, a material with high electron transport capacity, an electron blocking material, a material with high electron injection capacity, or a bipolar material (a material with both high electron transport capacity and high hole transport capacity).

[0320] Light-emitting devices can use low-molecular-weight compounds or high-molecular-weight compounds, and may also include inorganic compounds. The layers constituting the light-emitting device can be formed by methods such as vapor deposition (including vacuum vapor deposition), transfer printing, printing, inkjet printing, and coating.

[0321] For example, in addition to the light-emitting layer, a light-emitting device may also include one or more of the following: a hole injection layer, a hole transport layer, a hole barrier layer, an electron barrier layer, an electron transport layer, and an electron injection layer.

[0322] The hole injection layer is a layer that injects holes from the anode into the hole transport layer and contains a material with high hole injection properties. Materials with high hole injection properties can include aromatic amine compounds, composite materials containing both hole transport materials and acceptor materials (electron acceptor materials), etc.

[0323] The hole transport layer is a layer that transports holes injected from the anode through the hole injection layer to the light-emitting layer. The hole transport layer contains a hole-transporting material. Preferably, the hole transporting material is a substance with a hole mobility of 1 × 10⁻⁶ cm² / Vs or higher. However, any substance other than those mentioned above can be used, as long as its hole transportability is higher than its electron transportability. Preferably, the hole transporting material is a π-electron-rich heteroaromatic compound (e.g., carbazole derivatives, thiophene derivatives, furan derivatives, etc.) or an aromatic amine (a compound containing an aromatic amine skeleton), which are materials with high hole transportability.

[0324] The electron transport layer is the layer that transports electrons injected from the cathode through the electron injection layer to the light-emitting layer. The electron transport layer contains an electron transport material. Preferably, the electron transport material is a substance with an electron mobility of 1 × 10⁻⁶ cm² / Vs or higher. However, any substance other than those mentioned above can be used, as long as its electron transport capability is higher than its hole transport capability. As electron transport materials, metal complexes with a quinoline skeleton, metal complexes with a benzoquinoline skeleton, metal complexes with an oxazole skeleton, metal complexes with a thiazole skeleton, etc., can be used. Materials with high electron transport capabilities, such as oxadiazole derivatives, triazole derivatives, imidazole derivatives, oxazole derivatives, thiazole derivatives, phenobarbital derivatives, quinoline derivatives with quinoline ligands, benzoquinoline derivatives, quinoline derivatives, dibenzoquinoline derivatives, pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, nitrogen-containing heteroaromatic compounds, and other π-electron-deficient heteroaromatic compounds, can also be used.

[0325] The electron injection layer is a layer containing a material with high electron injection capability, through which electrons are injected from the cathode into the electron transport layer. Alkali metals, alkaline earth metals, or compounds containing these substances can be used as materials with high electron injection capability. Composite materials containing both electron transport materials and donor materials (electron donor materials) can also be used as materials with high electron injection capability.

[0326] As an electron injection layer, alkali metals, alkaline earth metals, or their compounds can be used, such as lithium, cesium, lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF₂), lithium 8-(hydroxyoxoline) (Liq), lithium 2-(2-pyridyl)phenol (LiPP), lithium 2-(2-pyridyl)-3-hydroxypyridine (LiPPy), lithium 4-phenyl-2-(2-pyridyl)phenol (LiPPP), lithium oxide (LiO₂x), cesium carbonate, etc.

[0327] Furthermore, materials with electron transport properties can also be used as the aforementioned electron injection layer. For example, compounds with non-shared electron pairs and electron-deficient heteroaromatic rings can be used in materials with electron transport properties. Specifically, compounds containing at least one of pyridine rings, diazine rings (pyrimidine rings, pyrazine rings, pyrazine rings), and triazine rings can be used.

[0328] For organic compounds with non-shared electron pairs, the lowest unoccupied molecular orbital (LUMO) is preferably above -3.6 eV and below -2.3 eV. Furthermore, cyclic voltammetry (CV), photoelectron spectroscopy, optical absorption spectroscopy, and inverse photoelectron spectroscopy are generally used to estimate the highest occupied molecular orbital (HOMO) and LUMO levels of organic compounds.

[0329] For example, 4,7-diphenyl-1,10-phenanthroline (BPhen), 2,9-bis(naphthyl-2-yl)-4,7-diphenyl-1,10-phenanthroline (NBPhen), diquinoline[2,3-a:2',3'-c]phenazine (HATNA), and 2,4,6-tris[3'-(pyridin-3-yl)biphenyl-3-yl]-1,3,5-triazine (TmPPPyTz) can be used in organic compounds with non-shared electron pairs. Furthermore, compared to BPhen, NBPhen exhibits a higher glass transition temperature (Tg) and better heat resistance.

[0330] The luminescent layer is a layer containing a luminescent substance. The luminescent layer may contain one or more luminescent substances. Furthermore, substances exhibiting luminescent colors such as blue, purple, blue-violet, green, yellow-green, yellow, orange, and red are appropriately used as luminescent substances. Additionally, substances emitting near-infrared light may also be used as luminescent substances.

[0331] Examples of luminescent materials include fluorescent materials, phosphorescent materials, TADF materials, and quantum dot materials.

[0332] Examples of fluorescent materials include pyrene derivatives, anthracene derivatives, triphenylene derivatives, fumonisin derivatives, carbazole derivatives, dibenzothiophene derivatives, dibenzofuran derivatives, dibenzoquinoline derivatives, quinoline derivatives, pyridine derivatives, pyrimidine derivatives, phenanthrene derivatives, and naphthalene derivatives.

[0333] Examples of phosphorescent materials include organometallic complexes (especially iridium complexes) with 4H-triazole, 1H-triazole, imidazole, pyrimidine, pyrazine, and pyridine skeletons, organometallic complexes (especially iridium complexes) with phenylpyridine derivatives having electron-withdrawing groups as ligands, platinum complexes, and rare earth metal complexes.

[0334] In addition to the luminescent material (guest material), the luminescent layer may also contain one or more organic compounds (host material, auxiliary material, etc.). One or more organic compounds may be hole transport materials and electron transport materials, or both. Furthermore, bipolar materials or TADF materials may also be used as one or more organic compounds.

[0335] For example, the luminescent layer is preferably a combination of a phosphorescent material, a hole transport material that readily forms excited-state complexes, and an electron transport material. By employing such a structure, ExTET (Exciplex-Triplet Energy Transfer), which utilizes energy transfer from the excited-state complex to the luminescent material (phosphorescent material), can be efficiently obtained. By selecting a mixture of materials that forms excited-state complexes whose wavelengths overlap with the absorption band of the lowest energy side of the luminescent material, energy transfer can be facilitated, resulting in efficient luminescence. This structure enables the simultaneous achievement of high efficiency, low-voltage operation, and long lifetime in the luminescent device.

[0336] At least a portion of the structural examples shown in this embodiment and the corresponding diagrams can be appropriately combined with other structural examples or diagrams.

[0337] At least a portion of this embodiment can be implemented in combination with other embodiments described in this specification.

[0338] Implementation Method 5 In this embodiment, an example of a display device according to one embodiment of the present invention, including a light-receiving device, is described.

[0339] In the display device of this embodiment, a pixel may include multiple sub-pixels having light-emitting devices that emit light of different colors. For example, a pixel may include three types of sub-pixels. Examples of these three types of sub-pixels include sub-pixels of red (R), green (G), and blue (B), and sub-pixels of yellow (Y), cyan (C), and magenta (M). Alternatively, a pixel may include four types of sub-pixels. Examples of these four types of sub-pixels include sub-pixels of R, G, B, and white (W), and sub-pixels of R, G, B, and Y.

[0340] There are no particular restrictions on the arrangement of subpixels; various arrangement methods can be used. Examples of subpixel arrangements include stripe arrangement, S-stripe arrangement, matrix arrangement, Delta arrangement, Bayer arrangement, Pentile arrangement, etc.

[0341] Furthermore, examples of the top surface shape of a sub-pixel include triangles, quadrilaterals (including rectangles and squares), pentagons, rounded corners of the aforementioned polygons, ellipses, and circles. Here, the top surface shape of the sub-pixel corresponds to the top surface shape of the light-emitting area of ​​the light-emitting device.

[0342] In a display device according to one embodiment of the present invention, the pixel may also include a light-receiving device.

[0343] In a display device where pixels include both light-emitting and light-receiving devices, the pixels have a light-receiving function, so the display device can detect the contact or proximity of an object while displaying an image. For example, not only can all sub-pixels included in the display device display images, but some sub-pixels can emit light as a light source and cause other sub-pixels to display images.

[0344] In one embodiment of the present invention, the display unit of the display device has light-emitting devices arranged in a matrix, thereby enabling the display of images. Additionally, the display unit also has light-receiving devices arranged in a matrix, and in addition to image display, it possesses one or both of imaging and sensing functions. The display unit can be used as an image sensor or a touch sensor. That is, by detecting light from the display unit, images can be captured or the proximity or contact of an object (fingers, hands, or pens, etc.) can be detected. Furthermore, the display device of one embodiment of the present invention can use the light-emitting devices as the light source for the sensor. Therefore, it is not necessary to separately provide a light-receiving unit and a light source with the display device, thus reducing the number of components in the electronic device.

[0345] In a display device according to one embodiment of the present invention, when light emitted by a light-emitting device included in the display section is reflected (or scattered) by an object, a light-receiving device can detect the reflected light (or scattered light), thereby enabling the capture of images or the detection of touch even in the dark.

[0346] When a light-receiving device is used in an image sensor, the display device can capture images using the light-receiving device. For example, the display device of this embodiment can be used as a scanner.

[0347] For example, image sensors can be used to acquire data based on fingerprints, palm prints, etc. In other words, biometric sensors can be integrated into the display device. By integrating biometric sensors into the display device, compared to having separate display devices and biometric sensors, the number of parts in the electronic device can be reduced, thereby enabling miniaturization and weight reduction of the electronic device.

[0348] Furthermore, when a light-receiving device is used in a touch sensor, the display device can use the light-receiving device to detect the approach or contact of an object.

[0349] As a light-receiving device, for example, a pn-type or pin-type photodiode can be used. The light-receiving device is used as a photoelectric conversion device (also called a photoelectric conversion element) to generate charge by detecting light incident on it. The amount of charge generated by the light-receiving device depends on the amount of light incident on it.

[0350] In particular, organic photodiodes with a layer containing organic compounds are preferred as light-receiving devices. Organic photodiodes are easy to make thin, lightweight and large-area, and have high flexibility in shape and design, thus they can be applied to a wide variety of display devices.

[0351] In one embodiment of the present invention, an organic EL device is used as a light-emitting device, and an organic photodiode is used as a light-receiving device. The organic EL device and the organic photodiode can be formed on the same substrate. Therefore, the organic photodiode can be installed in a display device using an organic EL device.

[0352] The pixels shown in Figures 18A and 18B include sub-pixels G, B, R, and PS.

[0353] The pixels shown in Figure 18A are arranged in a stripe pattern. The pixels shown in Figure 18B are arranged in a matrix pattern.

[0354] The pixels shown in Figures 18C and 18D include sub-pixels G, B, R, PS, and IRS.

[0355] Figures 18C and 18D show examples of a pixel arranged in two rows and three columns. The upper row (first row) has three subpixels (subpixel G, subpixel B, and subpixel R). In Figure 18C, the lower row (second row) has three subpixels (one subpixel PS and two subpixels IRS). On the other hand, in Figure 18D, the lower row (second row) has two subpixels (one subpixel PS and one subpixel IRS). Note that the layout of the subpixels is not limited to the structures in Figures 18A to 18D.

[0356] Sub-pixel R includes a light-emitting device that emits red light. Sub-pixel G includes a light-emitting device that emits green light. Sub-pixel B includes a light-emitting device that emits blue light.

[0357] Both the sub-pixel PS and the sub-pixel IRS include light-receiving devices. There are no particular limitations on the wavelength of light detected by the sub-pixel PS and the sub-pixel IRS.

[0358] The light-receiving area of ​​a subpixel (PS) is smaller than that of a subpixel (IRS). A smaller light-receiving area results in a narrower imaging range, which helps suppress blurring and improve resolution. Therefore, by using a subpixel (PS), imaging can be performed with higher clarity or resolution compared to using a subpixel (IRS). For example, a subpixel (PS) can be used for personal identification using fingerprints, palm prints, irises, vein shapes (including vein and artery shapes), or faces.

[0359] The light-receiving device included in the sub-pixel PS preferably detects visible light, and more preferably detects one or more of the following colors: blue, purple, blue-violet, green, yellow-green, yellow, orange, and red. Additionally, the light-receiving device included in the sub-pixel PS can also detect infrared light.

[0360] Additionally, subpixel IRS can be used in touch sensors (also known as direct touch sensors) or air touch sensors (also known as hover sensors, levitating touch sensors, contactless sensors, or non-contact sensors). The wavelength of light detected by the subpixel IRS can be appropriately determined depending on the application. For example, a subpixel IRS is preferably designed to detect infrared light. This allows for touch detection even in darkness.

[0361] Here, a touch sensor or air touch sensor can detect the approach or contact of an object (finger, hand, or pen, etc.). A touch sensor can detect an object through direct contact between the display device and the object. Alternatively, an air touch sensor can detect an object even without direct contact. For example, preferably, the display device can detect the object within a distance of 0.1 mm to 300 mm, more preferably 3 mm to 50 mm, between the display device and the object. By employing this structure, operation can be performed without direct contact between the object and the display device; in other words, the display device can be operated in a non-contact (contactless) manner. By adopting the above structure, the risk of the display device becoming dirty or damaged can be reduced, or the display device can be operated without direct contact with dirt (e.g., garbage or viruses) adhering to it.

[0362] By setting two light-receiving devices in a single pixel, two additional functions can be added in addition to the display function, thus realizing the multi-functionality of the display device.

[0363] Because high-definition imaging is required, subpixels (PS) are preferably placed among all the pixels included in the display device. On the other hand, compared to subpixels (PS), subpixels (IRS) used for touch sensors or air touch sensors do not require high detection accuracy; therefore, subpixels (IRS) can be placed among only a portion of the pixels included in the display device. By making the number of subpixels (IRS) included in the display device less than the number of subpixels (PS), the detection speed can be improved.

[0364] Here, the structure of the light-receiving device that can be used for sub-pixel PS and sub-pixel IRS is explained.

[0365] The light-receiving device includes at least an active layer between a pair of electrodes, which serves as a photoelectric conversion layer. In this specification, one of the electrodes is sometimes referred to as the pixel electrode and the other as the common electrode.

[0366] One electrode of the pair of electrodes included in the light-receiving device is used as the anode, and the other electrode is used as the cathode. The following explanation uses the case where the pixel electrode is used as the anode and the common electrode is used as the cathode as an example. That is, by applying a reverse bias voltage between the pixel electrode and the common electrode to drive the light-receiving device, the light incident on the light-receiving device can be detected, a charge can be generated, and the charge can be extracted in the form of a current.

[0367] The light-receiving device can also be manufactured using the same method as the light-emitting device. The island-shaped active layer (also known as the photoelectric conversion layer) included in the light-receiving device is not formed by patterning a metal mask, but by depositing a film that will become the active layer on one side and then processing it. Therefore, the island-shaped active layer can be formed with a uniform thickness. In addition, by setting a sacrificial layer on the active layer, damage to the active layer during the manufacturing process of the display device can be reduced, thereby improving the reliability of the light-receiving device.

[0368] Note that layers shared by the light-receiving and light-emitting devices sometimes have different functions in the light-emitting and light-receiving devices. In this specification, components are sometimes referred to according to their function in the light-emitting device. For example, a hole injection layer is used as a hole injection layer in the light-emitting device and as a hole transport layer in the light-receiving device. Similarly, an electron injection layer functions as both an electron injection layer and an electron transport layer in both the light-emitting and light-receiving devices. Furthermore, layers shared by the light-receiving and light-emitting devices sometimes have the same function in both the light-emitting and light-receiving devices. For example, a hole transport layer is used as a hole transport layer in both the light-emitting and light-receiving devices, and an electron transport layer is used as an electron transport layer in both the light-emitting and light-receiving devices.

[0369] The active layer of the light-receiving device comprises a semiconductor. Examples of such semiconductors include inorganic semiconductors such as silicon and organic semiconductors containing organic compounds. In this embodiment, an example of using an organic semiconductor as the semiconductor contained in the active layer is shown. Because of the use of an organic semiconductor, the light-emitting layer and the active layer can be formed using the same method (e.g., vacuum evaporation), and the manufacturing equipment can be shared, which is preferable.

[0370] Examples of electron-accepting organic semiconductor materials that can be used as n-type semiconductors in the active layer include fullerenes (e.g., C60, C70, etc.) and fullerene derivatives. Fullerenes have a soccer ball shape, which is energy stable. Fullerenes have deep (low) HOMO and LUMO energy levels. Because of their deep LUMO energy level, fullerenes exhibit extremely high electron acceptor activity. Generally, when π-electron conjugation (resonance), as in benzene, expands in a plane, electron donor activity increases. On the other hand, fullerenes, with their spherical shape, exhibit high electron acceptor activity despite the extensive expansion of π-electrons. This high electron acceptor activity allows for rapid and efficient charge separation, which is beneficial for light-receiving devices. Both C60 and C70 have broad absorption bands in the visible light region, especially C70, which has a larger π-electron conjugation class than C60 and also exhibits a broad absorption band in the long-wavelength region, making it a preferred choice. In addition, examples of fullerene derivatives include methyl [6,6]-phenyl-C71-butyrate (abbreviated as PC70BM), methyl [6,6]-phenyl-C61-butyrate (abbreviated as PC60BM), and 1',1'',4',4''-tetrahydro-bis[1,4]methanenaphthaleno[1,2:2',3',56,60:2'',3''][5,6]fullerene-C60 (abbreviated as ICBA).

[0371] Materials that can be used as n-type semiconductors include metal complexes with a quinoline skeleton, metal complexes with a benzoquinoline skeleton, metal complexes with a chloroazole skeleton, metal complexes with a thiazole skeleton, chlorodiazole derivatives, triazole derivatives, imidazole derivatives, chloroazole derivatives, thiazole derivatives, phenoline derivatives, quinoline derivatives, benzoquinoline derivatives, quinoline derivatives, dibenzoquinoline derivatives, pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, naphthalene derivatives, anthracene derivatives, coumarin derivatives, rhodamine derivatives, triazine derivatives, quinone derivatives, etc.

[0372] Examples of p-type semiconductor materials containing active layers include copper(II) phthalocyanine (CuPc), tetraphenyldibenzoperiflanthene (DBP), zinc phthalocyanine (ZnPc), tin phthalocyanine (SnPc), and quinacridone, which are organic semiconductor materials with electronic donor properties.

[0373] In addition, examples of materials that can be used as p-type semiconductors include carbazole derivatives, thiophene derivatives, furan derivatives, and compounds with aromatic amine skeletons. Furthermore, examples of materials that can be used as p-type semiconductors include naphthalene derivatives, anthracene derivatives, pyrene derivatives, triphenylene derivatives, benzo[a]furan derivatives, benzo[a]thiophene derivatives, indole derivatives, dibenzo[a]furan derivatives, dibenzo[a]thiophene derivatives, indole-carbazole derivatives, violet derivatives, phthalocyanine derivatives, naphthylphthalocyanine derivatives, quinacridone derivatives, polyphenylene oxide derivatives, poly[a]benzene oxide derivatives, poly[a]benzene oxide derivatives, poly[a]benzene oxide derivatives, polyvinylcarbazole derivatives, or polythiophene derivatives.

[0374] The HOMO energy level of organic semiconductor materials with electron donor properties is preferably shallower (higher) than that of organic semiconductor materials with electron acceptor properties. Similarly, the LUMO energy level of organic semiconductor materials with electron donor properties is preferably shallower (higher) than that of organic semiconductor materials with electron acceptor properties.

[0375] Preferably, spherical fullerenes are used as organic semiconductor materials with electron-accepting properties, and even more preferably, organic semiconductor materials with shapes similar to planar structures are used as organic semiconductor materials with electron-donating properties. Molecules with similar shapes tend to aggregate easily, and when the same type of molecules aggregate, the carrier transport can be improved because the energy levels of the molecular orbitals are similar.

[0376] For example, it is preferable to co-deposit an n-type semiconductor and a p-type semiconductor to form the active layer. Alternatively, an n-type semiconductor and a p-type semiconductor can be stacked to form the active layer.

[0377] The light-receiving device may also include layers other than the active layer, such as layers containing materials with high hole transport, materials with high electron transport, or bipolar materials (materials with both high electron and hole transport). Furthermore, it is not limited to these; it may also include layers containing materials with high hole injection, hole blocking materials, materials with high electron injection, or electron blocking materials.

[0378] Light-receiving devices can use low-molecular-weight compounds or high-molecular-weight compounds, and may also contain inorganic compounds. The layers constituting the light-receiving device can be formed by methods such as vapor deposition (including vacuum vapor deposition), transfer printing, printing, inkjet printing, and coating.

[0379] For example, polymers such as poly(3,4-ethylenedioxythiophene) / poly(styrene sulfonic acid) (PEDOT / PSS) and inorganic compounds such as molybdenum oxide and copper iodide (CuI) can be used as hole transport materials. Additionally, inorganic compounds such as zinc oxide (ZnO) can be used as electron transport materials.

[0380] Alternatively, the active layer can also use polymers such as poly[[4,8-bis[5-(2-ethylhexyl)-2-thiophene]benzo[1,2-b:4,5-b']dithienyl-2,6-diyl]-2,5-thiophenediyl[5,7-bis(2-ethylhexyl)-4,8-dioxo-4H,8H-benzo[1,2-c:4,5-c']dithienyl-1,3-diyl]] (abbreviated as PBDB-T) or PBDB-T derivatives, which serve as donors. For example, methods such as dispersing acceptor materials into PBDB-T or PBDB-T derivatives can be used.

[0381] Furthermore, three or more materials can be mixed as the active layer. For example, in order to expand the wavelength region, a third material can be mixed in addition to n-type and p-type semiconductor materials. In this case, the third material can be a low-molecular-weight compound or a high-molecular-weight compound.

[0382] The above describes the light-receiving device.

[0383] Figure 18E shows an example of a subpixel with a light-receiving device, while Figure 18F shows an example of a subpixel with a light-emitting device.

[0384] The pixel circuit PIX1 shown in Figure 18E includes a light-receiving device PD, transistors M11, M12, M13, and M14, and a capacitor C2. Here, an example is shown using a photodiode as the light-receiving device PD.

[0385] The cathode of the light-receiving device PD is electrically connected to wiring V1, and the anode is electrically connected to one of the source and drain electrodes of transistor M11. The gate of transistor M11 is electrically connected to wiring TX, and the other of its source and drain electrodes is electrically connected to one electrode of capacitor C2, one of the source and drain electrodes of transistor M12, and the gate of transistor M13. The gate of transistor M12 is electrically connected to wiring RES, and the other of its source and drain electrodes is electrically connected to wiring V2. One of the source and drain electrodes of transistor M13 is electrically connected to wiring V3, and the other of its source and drain electrodes is electrically connected to one of the source and drain electrodes of transistor M14. The gate of transistor M14 is electrically connected to wiring SE, and the other of its source and drain electrodes is electrically connected to wiring OUT1.

[0386] Wiring V1, wiring V2, and wiring V3 are each supplied with a constant potential. When the photodetector PD is driven with a reverse bias, a potential lower than that of wiring V1 is supplied to wiring V2. Transistor M12 is controlled by a signal supplied to wiring RES, causing the potential of the node connected to the gate of transistor M13 to be reset to the potential supplied to wiring V2. Transistor M11 is controlled by a signal supplied to wiring TX, controlling the timing of the potential changes of the aforementioned nodes according to the current flowing through the photodetector PD. Transistor M13 is used as an amplifying transistor to output the potential based on the aforementioned nodes. Transistor M14 is controlled by a signal supplied to wiring SE and is used as a selection transistor, which is used to read the output based on the potential of the aforementioned nodes using an external circuit connected to wiring OUT1.

[0387] The pixel circuit PIX2 shown in Figure 18F includes a light-emitting device EL, transistors M15, M16, and M17, and a capacitor C3. Here, an example using a light-emitting diode (LED) as the light-emitting device EL is shown. In particular, an organic LED device is preferred as the light-emitting device EL.

[0388] The gate of transistor M15 is electrically connected to wiring VG, one of its source and drain is electrically connected to wiring VS, and the other of its source and drain is electrically connected to one electrode of capacitor C3 and the gate of transistor M16. One of the source and drain of transistor M16 is electrically connected to wiring V4, and the other of its source and drain is electrically connected to the anode of light-emitting device EL and one of the source and drain of transistor M17. The gate of transistor M17 is electrically connected to wiring MS, and the other of its source and drain is electrically connected to wiring OUT2. The cathode of light-emitting device EL is electrically connected to wiring V5.

[0389] Wiring V4 and wiring V5 are each supplied with a constant potential. The anode side and cathode side of the light-emitting device EL can be set to a high potential and a potential lower than the anode side, respectively. Transistor M15, controlled by a signal supplied to wiring VG, is used as a selection transistor to control the selection state of the pixel circuit PIX2. Furthermore, transistor M16 is used as a drive transistor to control the current flowing through the light-emitting device EL based on the potential supplied to its gate. When transistor M15 is in the on state, the potential supplied to wiring VS is supplied to the gate of transistor M16, and the brightness of the light-emitting device EL can be controlled based on this potential. Transistor M17, controlled by a signal supplied to wiring MS, outputs the potential between transistor M16 and the light-emitting device EL to the outside via wiring OUT2.

[0390] In the display panel of this embodiment, the light-emitting devices can also emit light in a pulsed manner to display images. By shortening the driving time of the light-emitting devices, the power consumption of the display panel can be reduced and heat generation suppressed. In particular, organic EL devices have excellent frequency characteristics, so they are preferred. For example, the frequency can be above 1kHz and below 100MHz.

[0391] Here, the transistors M11, M12, M13 and M14 included in the pixel circuit PIX1, and the transistors M15, M16 and M17 included in the pixel circuit PIX2 are preferably transistors whose semiconductor layer forming their channels comprises metal oxide (oxide semiconductor).

[0392] Using metal oxide transistors with wider band gaps and lower carrier densities than silicon allows for extremely low off-state currents. Consequently, due to their small off-state currents, the charge stored in the capacitor connected in series with the transistor can be maintained for extended periods. Therefore, transistors M11, M12, and M15 connected in series with capacitor C2 or C3 are preferably transistors containing oxide semiconductors. Furthermore, by using transistors that similarly utilize oxide semiconductors in other transistors, manufacturing costs can be reduced.

[0393] Furthermore, transistors M11 to M17 can also be transistors whose semiconductor forming their channels comprises silicon. In particular, it is preferable to use highly crystalline silicon such as monocrystalline or polycrystalline silicon, as this can achieve high field-efficiency mobility and higher operating speed.

[0394] Furthermore, one or more of transistors M11 to M17 may be transistors containing oxide semiconductors, while the other transistors may be transistors containing silicon.

[0395] In Figures 18E and 18F, an n-channel transistor is used as the transistor, but a p-channel transistor can also be used.

[0396] The transistors included in pixel circuit PIX1 and pixel circuit PIX2 are preferably arranged on the same substrate. More preferably, the transistors included in pixel circuit PIX1 and pixel circuit PIX2 are mixed and formed in one region and arranged periodically.

[0397] Furthermore, it is preferable to provide one or more layers, including one or both transistors and capacitors, at a location overlapping with the light-receiving device (PD) or the light-emitting device (EL). This reduces the effective area occupied by each pixel circuit, thereby enabling a high-definition light-receiving or display section.

[0398] As described above, the display device of this embodiment, by incorporating two light-receiving devices within a single pixel, can add two additional functions besides the display function, thereby achieving multi-functionality. For example, it can realize high-definition video recording and sensing functions such as touch sensors or air touch sensors. Furthermore, by combining pixels with two light-receiving devices with pixels having other structures, the functionality of the display device can be further enhanced. For example, pixels including light-emitting devices that emit infrared light or various sensor devices can be used.

[0399] Implementation Method 6 In this embodiment, a high-definition display device is described.

[0400] [Example of a display panel structure] Wearable electronic devices used in VR, AR, etc., can provide 3D images by utilizing parallax. In this case, the image for the right eye and the image for the left eye need to be displayed in the right eye's field of view and the left eye's field of view, respectively. Here, the display unit of the display device can be a horizontally elongated rectangle, and pixels located outside the right and left eye's field of view do not contribute to the display, so these pixels are always displayed as black.

[0401] The display panel has two areas, one for the right eye and one for the left eye. Preferably, no pixels are placed in the outer areas that do not contribute to the display. This reduces the power consumption required for pixel writing. Furthermore, by reducing the load on source lines, gate lines, etc., a higher frame rate display can be achieved. This allows for the display of smooth dynamic images, thus improving realism.

[0402] Figure 19A shows an example of a display panel structure. In Figure 19A, a left-eye display unit 702L and a right-eye display unit 702R are disposed on the inner side of a substrate 701. Note that in addition to the display units 702L and 702R, driving circuits, wiring, ICs, FPCs, etc., may also be disposed on the substrate 701.

[0403] The display units 702L and 702R shown in Figure 19A have a square top surface shape.

[0404] The top surface shape of display units 702L and 702R can also be other regular polygons. Figure 19B shows an example of a regular hexagon, Figure 19C shows an example of a regular octagon, Figure 19D shows an example of a regular decagon, and Figure 19E shows an example of a regular dodecagon. Thus, by using polygons with an even number of angles, the shape of the display unit can be made symmetrical. Note that polygons that are not regular polygons can also be used. Furthermore, regular polygons or polygons with rounded corners can also be used.

[0405] Note that because the display unit is composed of pixels arranged in a matrix, the straight lines of the outline of each display unit are not strictly straight lines, but rather have stepped sections. In particular, the straight lines that are not parallel to the pixel arrangement direction have a stepped top surface shape. Note that since the user views the image without seeing the shape of the pixels, even if the tilted outline of the display unit is strictly stepped, it can be considered a straight line. Similarly, even if the curved sections of the outline of the display unit are strictly stepped, they can be considered curved.

[0406] Figure 19F shows an example where the top surface of display unit 702L and display unit 702R is circular.

[0407] Furthermore, the top surface shapes of display units 702L and 702R can also be asymmetrical. Alternatively, they can be regular polygons.

[0408] Figure 19G shows an example where the top surfaces of display units 702L and 702R are asymmetrical octagons. Figure 19H shows an example where they are regular heptagons. Thus, even though the top surfaces of display units 702L and 702R are asymmetrical, they are preferably configured to be symmetrical. This provides an image without discomfort.

[0409] In the above description, although the display part is shown as a two-part structure, a continuous shape can also be used.

[0410] Figure 19I shows an example of the connection of two circular display units as in Figure 19F. Furthermore, Figure 19J shows an example of the connection of two regular octagonal display units as in Figure 19C.

[0411] The above illustrates an example of the structure of a display panel.

[0412] At least a portion of the structural examples shown in this embodiment and the corresponding diagrams can be appropriately combined with other structural examples or diagrams.

[0413] At least a portion of this embodiment can be implemented in combination with other embodiments described in this specification.

[0414] Implementation Method 7 In this embodiment, a metal oxide (also called an oxide semiconductor) that can be used with the OS transistor described in the above embodiments is explained.

[0415] The metal oxide used in the OS transistor preferably contains at least indium or zinc, more preferably indium and zinc. For example, the metal oxide preferably contains indium, M (M is selected from one or more of gallium, aluminum, yttrium, tin, silicon, boron, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, magnesium, and cobalt), and zinc. In particular, M is preferably selected from one or more of gallium, aluminum, yttrium, and tin, more preferably gallium.

[0416] Metal oxides can be formed by sputtering, chemical vapor deposition (CVD) such as metal-organic chemical vapor deposition (MOCVD), or atomic layer deposition (ALD).

[0417] The following is an example of a metal oxide containing indium (In), gallium (Ga), and zinc (Zn). Note that oxides containing indium (In), gallium (Ga), and zinc (Zn) are sometimes referred to as In-Ga-Zn oxides.

[0418] <Classification of Crystal Structures> Examples of crystalline structures for oxide semiconductors include amorphous (including completely amorphous), CAAC (c-axis-aligned crystalline), nc (nanocrystalline), CAC (cloud-aligned composite), single crystal, and polycrystalline.

[0419] X-ray diffraction (XRD) spectroscopy can be used to evaluate the crystal structure of films or substrates. For example, the XRD spectrum obtained by GIXD (Grazing-Incidence XRD) can be used for evaluation. Furthermore, the GIXD method is also called the thin film method or the Seemann-Bohlin method. Hereinafter, the XRD spectrum obtained by GIXD measurement will sometimes be simply referred to as the XRD spectrum.

[0420] For example, the peak shapes of the XRD spectrum of a quartz glass substrate are roughly symmetrical from left to right. On the other hand, the peak shapes of the XRD spectrum of an In-Ga-Zn oxide film with a crystalline structure are not symmetrical from left to right. The asymmetry of the XRD peak shapes indicates the presence of crystals in the film or substrate. In other words, unless the XRD peak shapes are symmetrical from left to right, it cannot be said that the film or substrate is in an amorphous state.

[0421] Furthermore, the crystal structure of the film or substrate can be evaluated using diffraction patterns observed by nano-beam electron diffraction (NBED). For example, the observation of a halo pattern in the diffraction pattern of a quartz glass substrate confirms that the quartz glass is in an amorphous state. In contrast, a spot-like pattern without a halo was observed in the diffraction pattern of an In-Ga-Zn oxide film formed at room temperature. Therefore, it can be inferred that the In-Ga-Zn oxide film formed at room temperature is in an intermediate state, neither monocrystalline nor polycrystalline nor amorphous, and it cannot be concluded that the In-Ga-Zn oxide film is amorphous.

[0422] <<Structure of Oxide Semiconductors>> Furthermore, when focusing on the structure of oxide semiconductors, the classification of oxide semiconductors sometimes differs from the classifications described above. For example, oxide semiconductors can be classified into single-crystal oxide semiconductors and other non-single-crystal oxide semiconductors. Examples of non-single-crystal oxide semiconductors include, for instance, CAAC-OS and nc-OS, as mentioned above. In addition, non-single-crystal oxide semiconductors include polycrystalline oxide semiconductors, a-like OS (amorphous-like oxide semiconductor), and amorphous oxide semiconductors, etc.

[0423] Here, we will explain the details of CAAC-OS, nc-OS, and a-like OS.

[0424] [CAAC-OS] CAAC-OS is an oxide semiconductor comprising multiple crystalline regions, whose c-axis is aligned in a specific direction. This specific direction refers to the thickness direction of the CAAC-OS film, the normal direction of the formed surface of the CAAC-OS film, or the normal direction of the surface of the CAAC-OS film. Furthermore, a crystalline region is a region exhibiting a periodic atomic arrangement. Note that when atomic arrangement is considered as lattice arrangement, a crystalline region is also a region with a consistent lattice arrangement. Moreover, CAAC-OS has a region where multiple crystalline regions are connected in the ab-plane direction, and sometimes this region exhibits distortion. Distortion refers to the portion of the lattice arrangement direction that changes between lattice-aligned regions and other lattice-aligned regions within the region where multiple crystalline regions are connected. In other words, CAAC-OS refers to an oxide semiconductor with c-axis alignment but no obvious alignment in the ab-plane direction.

[0425] Furthermore, each of the aforementioned crystalline regions is composed of one or more microcrystals (crystals with a maximum diameter of less than 10 nm). When a crystalline region is composed of a single microcrystal, the maximum diameter of that region is less than 10 nm. Conversely, when a crystalline region is composed of multiple microcrystals, the size of that region can sometimes be around tens of nm.

[0426] Furthermore, in In-Ga-Zn oxides, CAAC-OS tends to have a layered crystal structure (also called a layered structure) consisting of layers containing indium (In) and oxygen (hereinafter, In layers) and layers containing gallium (Ga), zinc (Zn), and oxygen (hereinafter, (Ga,Zn) layers). In addition, indium and gallium can substitute for each other. Therefore, sometimes the (Ga,Zn) layer contains indium. Also, sometimes the In layer contains gallium. Note that sometimes the In layer contains zinc. This layered structure is observed, for example, as a lattice image in high-resolution TEM (Transmission Electron Microscope) images.

[0427] For example, when performing structural analysis on CAAC-OS films using an XRD apparatus, peaks representing c-axis alignment are detected at or near 2θ = 31° in out-of-plane XRD measurements using θ / 2θ scanning. Note that the position (2θ value) of the peaks representing c-axis alignment can vary depending on the type and composition of the metallic elements constituting CAAC-OS.

[0428] Furthermore, for example, multiple bright spots (spots) were observed in the electron diffraction pattern of the CAAC-OS film. Additionally, when the spot of the incident electron beam passing through the sample (also known as the direct spot) is taken as the center of symmetry, one spot and other spots were observed at point-symmetrical positions.

[0429] When observing the crystalline region from the aforementioned specific directions, although the lattice arrangement in this region is primarily hexagonal, the unit lattice is not limited to a regular hexagon; there are also cases where it is non-regular hexagonal. Furthermore, in the aforementioned distortions, pentagonal, heptagonal, and other lattice arrangements are sometimes observed. Moreover, no clear grain boundary is observed near the distortion in CAAC-OS. That is, the lattice arrangement distortion inhibits grain boundary formation. This may be because CAAC-OS can accommodate distortion due to the low density of oxygen atoms along the ab plane or changes in the bonding distance between atoms caused by the substitution of metal atoms.

[0430] Furthermore, crystalline structures with clearly defined grain boundaries are referred to as polycrystalline. Grain boundaries act as recombination centers, trapping carriers and potentially leading to a decrease in the transistor's on-state current and field-effect mobility. Therefore, CAAC-OS, which lacks clearly defined grain boundaries, is one of the crystalline oxides that provides an excellent crystalline structure for the semiconductor layer of the transistor. Note that a Zn-containing structure is preferred for constructing CAAC-OS. For example, In-Zn oxides and In-Ga-Zn oxides are preferred because they can further suppress grain boundary formation compared to In oxides.

[0431] CAAC-OS is an oxide semiconductor with high crystallinity and no clearly defined grain boundaries. Therefore, it can be said that in CAAC-OS, the reduction in electron mobility due to grain boundaries is less likely to occur. Furthermore, the crystallinity of oxide semiconductors can sometimes decrease due to the incorporation of impurities or the formation of defects; therefore, CAAC-OS can be considered an oxide semiconductor with few impurities and defects (such as oxygen vacancies). Consequently, oxide semiconductors containing CAAC-OS exhibit stable physical properties. Thus, oxide semiconductors containing CAAC-OS possess high heat resistance and high reliability. In addition, CAAC-OS is also stable against high temperatures (so-called thermal budget) in the manufacturing process. Therefore, by using CAAC-OS in OS transistors, process flexibility can be increased.

[0432] [nc-OS] In nc-OS, the atomic arrangement in tiny regions (e.g., regions larger than 1 nm and smaller than 10 nm, particularly regions larger than 1 nm and smaller than 3 nm) exhibits periodicity. In other words, nc-OS possesses tiny crystallinity. Furthermore, for example, these tiny crystallinity sizes are between 1 nm and 10 nm, particularly between 1 nm and 3 nm; these tiny crystallinity sizes are referred to as nanocrystals. Moreover, no regularity in crystallinity orientation is observed between different nanocrystals in nc-OS. Therefore, no alignment is observed in the overall film. Thus, sometimes nc-OS is indistinguishable from a-like OS or amorphous oxide semiconductors in certain analytical methods. For example, when performing structural analysis on nc-OS films using an XRD apparatus, no peaks indicating crystallinity are detected in out-of-plane XRD measurements using θ / 2θ scanning. Furthermore, when performing electron diffraction (also known as selected area electron diffraction) on nc-OS films using an electron beam with a beam diameter larger than that of nanocrystals (e.g., larger than 50 nm), a diffraction pattern resembling a halo pattern is observed. On the other hand, when electron diffraction (also known as nano-beam electron diffraction) is performed on nc-OS films using an electron beam whose beam diameter is close to or smaller than the size of nanocrystals (e.g., more than 1 nm and less than 30 nm), sometimes an electron diffraction pattern of multiple spots is observed in an annular region centered on a direct spot.

[0433] [a-like OS] a-like OS is an oxide semiconductor with a structure intermediate between nc-OS and amorphous oxide semiconductors. a-like OS contains voids or low-density regions. That is, a-like OS has lower crystallinity than nc-OS and CAAC-OS. Furthermore, the hydrogen concentration in a-like OS films is higher than that in nc-OS and CAAC-OS films.

[0434] <<The Structure of Oxide Semiconductors>> Next, the details of the aforementioned CAC-OS will be explained. Furthermore, CAC-OS is related to material composition.

[0435] [CAC-OS] CAC-OS, for example, refers to a composition in which elements are non-uniformly distributed within a metal oxide, wherein the size of the material containing the non-uniformly distributed elements is 0.5 nm or more and 10 nm or less, preferably 1 nm or more and 3 nm or approximately. Note that, below, the state in which one or more metal elements are non-uniformly distributed within a metal oxide and the regions containing those metal elements are mixed is also referred to as mosaic or patch-like, wherein the size of the region is 0.5 nm or more and 10 nm or less, preferably 1 nm or more and 3 nm or approximately.

[0436] Furthermore, CAC-OS refers to a structure in which the material is divided into a first region and a second region, forming a mosaic-like structure, with the first region distributed throughout the film (hereinafter also referred to as cloud-like). In other words, CAC-OS refers to a composite metal oxide having a structure that combines the first and second regions.

[0437] Here, the atomic ratios of In, Ga, and Zn relative to the metal elements constituting the CAC-OS in In-Ga-Zn oxide are denoted as [In], [Ga], and [Zn]. For example, in the CAC-OS of In-Ga-Zn oxide, a first region is a region where [In] is greater than [In] in the composition of the CAC-OS film. Furthermore, a second region is a region where [Ga] is greater than [Ga] in the composition of the CAC-OS film. Alternatively, for example, a first region is a region where [In] is greater than [In] in the second region and [Ga] is less than [Ga] in the second region. Furthermore, a second region is a region where [Ga] is greater than [Ga] in the first region and [In] is less than [In] in the first region.

[0438] Specifically, the first region mentioned above is a region whose main component is indium oxide or indium zinc oxide. Furthermore, the second region mentioned above is a region whose main component is gallium oxide or gallium zinc oxide. In other words, the first region can be referred to as a region whose main component is In. Furthermore, the second region can be referred to as a region whose main component is Ga.

[0439] Note that sometimes the clear boundaries between the first region and the second region mentioned above are not observable.

[0440] Furthermore, CAC-OS in In-Ga-Zn oxides refers to a structure in which regions dominated by Ga and regions dominated by In are irregularly arranged in a mosaic pattern within a material containing In, Ga, Zn, and O. Therefore, it can be inferred that CAC-OS has a structure with uneven distribution of metallic elements.

[0441] CAC-OS can be formed, for example, by sputtering without intentionally heating the substrate. When forming CAC-OS by sputtering, one or more gases selected from inert gases (typically argon), oxygen gases, and nitrogen gases can be used as the deposition gas. Furthermore, the lower the oxygen gas flow rate in the total flow rate of the deposition gas during deposition, the better. For example, the oxygen gas flow rate in the total flow rate of the deposition gas during deposition should be 0% or more and less than 30%, preferably 0% or more and less than 10%.

[0442] For example, in CAC-OS of In-Ga-Zn oxide, based on EDX-mapping images obtained by Energy Dispersive X-ray spectroscopy (EDX), a structure with an unevenly distributed mixture of regions with In as the main component (first region) and regions with Ga as the main component (second region) can be identified.

[0443] Here, the first region has higher conductivity than the second region. That is, when carriers flow through the first region, it exhibits the conductivity of a metal oxide. Therefore, when the first region is distributed in a cloud-like manner within the metal oxide, a high field mobility (μ) can be achieved.

[0444] On the other hand, the second region is a region with higher insulation than the first region. That is, when the second region is distributed in a metal oxide, leakage current can be suppressed.

[0445] When CAC-OS is used in transistors, the complementary effect of conductivity arising from the first region and insulation arising from the second region enables CAC-OS to possess switching functionality (the function of controlling on / off). In other words, a portion of the CAC-OS material exhibits conductivity while another portion exhibits insulation, resulting in a semiconductor function within the overall material. By separating the conductivity and insulation functions, each function can be maximized. Therefore, by using CAC-OS in transistors, large on-state current (Ion), high field-efficiency mobility (μ), and excellent switching performance can be achieved.

[0446] Furthermore, transistors using CAC-OS exhibit high reliability. Therefore, CAC-OS is best suited for various semiconductor devices, such as display devices.

[0447] Oxide semiconductors possess various structures and properties. In one embodiment of the present invention, the oxide semiconductor may also include two or more of the following: amorphous oxide semiconductor, polycrystalline oxide semiconductor, a-like OS, CAC-OS, nc-OS, and CAAC-OS.

[0448] <Transistors with oxide semiconductor properties> Next, the use of the aforementioned oxide semiconductor in transistors will be explained.

[0449] By using the aforementioned oxide semiconductors in transistors, transistors with high field-effect mobility can be realized. Furthermore, transistors with high reliability can be achieved.

[0450] It is preferable to use oxide semiconductors with low carrier concentrations in transistors. For example, the carrier concentration in the oxide semiconductor is 1×10¹⁷ cm⁻³ or less, preferably 1×10¹⁵ cm⁻³ or less, more preferably 1×10¹³ cm⁻³ or less, further preferably 1×10¹¹ cm⁻³ or less, and even more preferably less than 1×10¹⁰ cm⁻³ and greater than 1×10⁻⁹ cm⁻³. When the purpose is to reduce the carrier concentration of the oxide semiconductor film, the impurity concentration in the oxide semiconductor film can be reduced to reduce the defect state density. In this specification, the state of low impurity concentration and low defect state density is referred to as high purity nature or substantially high purity nature. Furthermore, oxide semiconductors with low carrier concentrations are sometimes referred to as high purity nature or substantially high purity nature oxide semiconductors.

[0451] Because high-purity or essentially high-purity oxide semiconductor films have a low defect state density, they may also have a low trap state density.

[0452] Furthermore, the charge trapped in the trap state of an oxide semiconductor takes a relatively long time to dissipate, sometimes acting like a fixed charge. Therefore, the electrical properties of transistors forming channel formation regions in oxide semiconductors with high trap state density are sometimes unstable.

[0453] Therefore, reducing the impurity concentration in the oxide semiconductor is effective in stabilizing the electrical properties of the transistor. To further reduce the impurity concentration in the oxide semiconductor, it is preferable to also reduce the impurity concentration in the adjacent film. Examples of impurities include hydrogen, nitrogen, alkali metals, alkaline earth metals, iron, nickel, and silicon. Note that impurities in an oxide semiconductor refer to elements other than the main components constituting the oxide semiconductor. For example, elements with a concentration less than 0.1 atomic percent can be considered impurities.

[0454] <Impurities> Here, we will explain the effects of various impurities in oxide semiconductors.

[0455] When an oxide semiconductor contains silicon or carbon, one of the elements in Group 14, defect states are formed in the oxide semiconductor. Therefore, the concentration of silicon or carbon in the oxide semiconductor or near the interface with the oxide semiconductor (the concentration measured by secondary ion mass spectrometry) is set to 2 × 10¹⁸ atoms / cm³ or less, preferably 2 × 10¹⁷ atoms / cm³ or less.

[0456] Furthermore, when oxide semiconductors contain alkali metals or alkaline earth metals, defect states can sometimes be formed, thus creating carriers. Therefore, transistors using oxide semiconductors containing alkali metals or alkaline earth metals tend to have always-on characteristics. Therefore, the concentration of alkali metals or alkaline earth metals in the oxide semiconductor, as measured by SIMS, should be 1 × 10¹⁸ atoms / cm³ or less, preferably 2 × 10¹⁶ atoms / cm³ or less.

[0457] When oxide semiconductors contain nitrogen, electrons are readily generated as carriers, increasing the carrier concentration and resulting in n-type polarization. Consequently, transistors using nitrogen-containing oxide semiconductors tend to exhibit always-on characteristics. Alternatively, when nitrogen is included in the oxide semiconductor, trapped states can sometimes form. As a result, the electrical properties of the transistor can sometimes be unstable. Therefore, the nitrogen concentration in the oxide semiconductor, measured using SIMS, is set to be below 5 × 10¹⁹ atoms / cm³, preferably below 5 × 10¹⁸ atoms / cm³, more preferably below 1 × 10¹⁸ atoms / cm³, and even more preferably below 5 × 10¹⁷ atoms / cm³.

[0458] Hydrogen contained in oxide semiconductors reacts with oxygen bonded to metal atoms to form water, thus sometimes creating oxygen vacancies. When hydrogen enters these oxygen vacancies, electrons are sometimes generated as carriers. Furthermore, sometimes a portion of the hydrogen bonds with oxygen bonded to metal atoms, generating electrons as carriers. Therefore, transistors using oxide semiconductors containing hydrogen tend to have always-on characteristics. Thus, it is preferable to minimize the amount of hydrogen in the oxide semiconductor. Specifically, the hydrogen concentration in the oxide semiconductor, measured using SIMS, is set to be less than 1 × 10²⁰ atoms / cm³, preferably less than 1 × 10¹⁹ atoms / cm³, more preferably less than 5 × 10¹⁸ atoms / cm³, and even more preferably less than 1 × 10¹⁸ atoms / cm³.

[0459] By using oxide semiconductors with sufficiently reduced impurities in the channel formation region of a transistor, the transistor can be made to have stable electrical characteristics.

[0460] At least a portion of this embodiment can be implemented in combination with other embodiments described in this specification.

[0461] Implementation Method 8 In this embodiment, an electronic device according to one embodiment of the present invention is illustrated using Figures 18A to 23F.

[0462] The electronic device of this embodiment includes a display device according to one embodiment of the present invention. The display device according to one embodiment of the present invention is easily made high-definition, high-resolution, and large-scale. Therefore, the display device according to one embodiment of the present invention can be used in the display section of various electronic devices.

[0463] Furthermore, the display device according to one embodiment of the present invention can be manufactured at low cost, thereby reducing the manufacturing cost of electronic devices.

[0464] As electronic devices, in addition to electronic devices with large screens such as televisions, desktop or laptop personal computers, monitors for computers, digital signage, and large game consoles such as pinball machines, other examples include digital cameras, digital camcorders, digital photo frames, mobile phones, portable game consoles, portable information terminals, and audio playback devices.

[0465] In particular, because the display device of one embodiment of the present invention can improve clarity, it can be appropriately used in electronic devices that include a small display section. Examples of such electronic devices include, for example, information terminal devices (wearable devices) such as watch-type and bracelet-type devices, VR devices such as head-mounted displays, and AR devices such as glasses-type displays. Furthermore, examples of wearable devices include SR (Substitutional Reality) devices and MR (Mixed Reality) devices.

[0466] A display device according to one embodiment of the present invention preferably has extremely high resolution, such as HD (1280×720 pixels), FHD (1920×1080 pixels), WQHD (2560×1440 pixels), WQXGA (2560×1600 pixels), 4K2K (3840×2160 pixels), 8K4K (7680×4320 pixels), etc. Particularly preferred is 4K2K, 8K4K, or higher resolution. Furthermore, the pixel density (clarity) in the display device according to one embodiment of the present invention is preferably 300 ppi or higher, more preferably 500 ppi or higher, further preferably 1000 ppi or higher, even more preferably 2000 ppi or higher, still more preferably 3000 ppi or higher, still more preferably 5000 ppi or higher, and still more preferably 7000 ppi or higher. By using the aforementioned high-resolution or high-definition display devices, the sense of realism and depth can be further enhanced in personal electronic devices such as portable or home-use devices.

[0467] The electronic device of this embodiment can be assembled along the curved surfaces of the inner or outer walls of a house or high-rise building, or the interior or exterior decoration of a car.

[0468] The electronic device in this embodiment may also include an antenna. By receiving signals through the antenna, images and information can be displayed on the display unit. Furthermore, when the electronic device includes both an antenna and a secondary battery, contactless power transmission can be achieved using the antenna.

[0469] The electronic device in this embodiment may also include a sensor (which has the function of sensing, detecting, and measuring factors such as force, displacement, position, velocity, acceleration, angular velocity, rotational speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, tilt, vibration, odor, or infrared radiation).

[0470] The electronic device of this embodiment can have various functions. For example, it can have the following functions: displaying various information (still images, moving images, text images, etc.) on the display unit; touch panel function; displaying calendar, date or time, etc.; executing various software (programs); performing wireless communication function; reading programs or data stored in the storage medium; etc.

[0471] The electronic device 6500 shown in Figure 20A is a portable information terminal device that can be used as a smartphone.

[0472] The electronic device 6500 includes a housing 6501, a display unit 6502, a power button 6503, a button 6504, a speaker 6505, a microphone 6506, a camera 6507, and a light source 6508. The display unit 6502 has a touch panel function.

[0473] A display device according to an embodiment of the present invention can be applied to the display unit 6502.

[0474] Figure 20B is a cross-sectional view of one end of the microphone 6506, including the housing 6501.

[0475] A light-transmitting protective member 6510 is provided on one side of the display surface of the housing 6501. The space surrounded by the housing 6501 and the protective member 6510 contains a display panel 6511, an optical member 6512, a touch sensor panel 6513, a printed circuit board 6517, a battery 6518, etc.

[0476] The display panel 6511, optical component 6512 and touch sensor panel 6513 are fixed to the protective component 6510 using an adhesive layer (not shown).

[0477] In the area outside the display unit 6502, a portion of the display panel 6511 is folded back, and this folded portion is connected to an FPC 6515. An IC 6516 is mounted on the FPC 6515. The FPC 6515 is connected to terminals disposed on a printed circuit board 6517.

[0478] The display panel 6511 can use a flexible display (a flexible display device) according to one embodiment of the present invention. This allows for the realization of an extremely lightweight electronic device. Furthermore, since the display panel 6511 is extremely thin, a large-capacity battery 6518 can be installed while minimizing the thickness of the electronic device. Additionally, by folding a portion of the display panel 6511 to provide a connection portion with the FPC 6515 on the back of the pixel portion, a narrow-bezel electronic device can be realized.

[0479] Figure 21A shows an example of a television set. In the television set 7100, a display unit 7000 is assembled in a housing 7101. The structure in which the housing 7101 is supported by a bracket 7103 is shown here.

[0480] A display device according to an embodiment of the present invention can be applied to the display unit 7000.

[0481] The television 7100 shown in FIG. 21A can be operated using the operation switch provided in the housing 7101 and the separately provided remote control 7111. Alternatively, a touch sensor can be provided in the display unit 7000, allowing operation of the television 7100 by touching the display unit 7000 with a finger or similar object. Furthermore, the remote control 7111 can also have a display unit that shows information output from the remote control 7111. Using the operation keys or touch panel provided in the remote control 7111, channel and volume can be adjusted, and the images displayed on the display unit 7000 can be manipulated.

[0482] In addition, the 7100 television set includes a receiver and a modem. The receiver can be used to receive general television broadcasts. Furthermore, the modem connects to a wired or wireless communication network, enabling one-way (from sender to receiver) or two-way (between sender and receiver, or between receivers, etc.) information communication.

[0483] Figure 21B shows an example of a laptop computer. The laptop computer 7200 includes a casing 7211, a keyboard 7212, a pointing device 7213, an external connection port 7214, etc. A display unit 7000 is assembled in the casing 7211.

[0484] A display device according to an embodiment of the present invention can be applied to the display unit 7000.

[0485] Figures 21C and 21D show an example of a digital signage.

[0486] The digital signage 7300 shown in Figure 21C includes a housing 7301, a display unit 7000, and a speaker 7303. It may also include LEDs, operation keys (including a power switch or operation switch), connection terminals, various sensors, a microphone, etc.

[0487] Figure 21D shows a digital signage 7400 mounted on a cylindrical column 7401. The digital signage 7400 includes a display section 7000 disposed along the curved surface of the column 7401.

[0488] In Figures 21C and 21D, a display device including a transistor according to an embodiment of the present invention can be applied to the display unit 7000.

[0489] The larger the display unit (7000), the more information it can provide at once. A larger display unit (7000) is also more likely to attract attention, which can improve the effectiveness of advertising.

[0490] By using a touch panel for the display unit 7000, not only can static or dynamic images be displayed on the display unit 7000, but users can also operate it intuitively, which is superior. In addition, when used to provide information such as route information or traffic information, the intuitive operation can improve ease of use.

[0491] As shown in Figures 21C and 21D, the digital signage 7300 or 7400 is preferably able to wirelessly communicate with a user's smartphone or other information terminal device 7311 or 7411. For example, advertising information displayed on the display unit 7000 can be displayed on the screen of the information terminal device 7311 or 7411. Furthermore, the display on the display unit 7000 can be switched by operating the information terminal device 7311 or 7411.

[0492] Furthermore, the game can be executed on the digital signage 7300 or 7400 using the screen of information terminal device 7311 or 7411 as the operating unit (controller). Thus, multiple users can participate in the game simultaneously and enjoy the experience.

[0493] Figure 22A is an external view of the camera 8000 with the viewfinder 8100 installed.

[0494] The camera 8000 includes a housing 8001, a display unit 8002, operation buttons 8003, a shutter button 8004, etc. Furthermore, the camera 8000 is equipped with a detachable lens 8006. In the camera 8000, the lens 8006 and the housing 8001 can also be formed as a single unit.

[0495] The camera 8000 can take pictures by pressing the shutter button 8004 or touching the display 8002, which is used as a touch panel.

[0496] The housing 8001 includes an insert with electrodes, which can be connected to the viewfinder 8100 and to a flash unit, etc.

[0497] The viewfinder 8100 includes a housing 8101, a display unit 8102, and buttons 8103, etc.

[0498] The housing 8101 is mounted to the camera 8000 via an inserter that fits into the camera 8000. The viewfinder 8100 can display images received from the camera 8000 on the display unit 8102.

[0499] Button 8103 is used as a power button, etc.

[0500] The display device according to one embodiment of the present invention can be used in the display unit 8002 of a camera 8000 and the display unit 8102 of a viewfinder 8100. Alternatively, a viewfinder may be built into the camera 8000.

[0501] Figure 22B is an external view of the 8200 head-mounted display.

[0502] The head-mounted display 8200 includes a mounting section 8201, a lens 8202, a main body 8203, a display section 8204, and a cable 8205. Furthermore, a battery 8206 is built into the mounting section 8201.

[0503] Power is supplied from battery 8206 to main body 8203 via cable 8205. Main body 8203 is equipped with a wireless receiver and can display received image information on display unit 8204. In addition, main body 8203 has a camera, which can be used as an input method to utilize information from the user's eye movements or eyelid movements.

[0504] Furthermore, multiple electrodes can be provided at the user-contacted location of the mounting unit 8201 to detect the current flowing through the electrodes in response to the user's eye movements, thereby enabling the recognition of the user's gaze. Additionally, it can also monitor the user's pulse based on the current flowing through the electrodes. The mounting unit 8201 can incorporate various sensors such as temperature sensors, pressure sensors, and acceleration sensors, and may also have functions such as displaying the user's biometric information on the display unit 8204 or changing the image displayed on the display unit 8204 in sync with the user's head movements.

[0505] A display device according to an embodiment of the present invention can be applied to the display unit 8204.

[0506] Figures 22C to 22E are external views of the head-mounted display 8300. The head-mounted display 8300 includes a housing 8301, a display unit 8302, a strap-shaped fixing tool 8304, and a pair of lenses 8305.

[0507] The user can see the display on the display unit 8302 through the lens 8305. Preferably, the display unit 8302 is curved, as this allows the user to experience a high degree of realism. Furthermore, by viewing the image displayed on different areas of the display unit 8302 through the lens 8305, it is possible to perform 3D displays utilizing parallax. Moreover, one embodiment of the present invention is not limited to a structure with one display unit 8302; two display units 8302 may also be provided, with one display unit positioned for each of the user's eyes.

[0508] The display device according to one embodiment of the present invention can be used in the display unit 8302. The display device according to one embodiment of the present invention can also achieve extremely high resolution. For example, as shown in FIG22E, even when the display is magnified using the lens 8305, the pixels are not easily visible to the user. That is to say, the display unit 8302 can be used to allow the user to see images with a higher degree of realism.

[0509] Figure 22F is an external view of the goggle-type head-mounted display 8400. The head-mounted display 8400 includes a pair of housings 8401, a mounting part 8402, and a buffer member 8403. Each of the pair of housings 8401 is provided with a display unit 8404 and a lens 8405. By displaying different images on the pair of display units 8404, three-dimensional display utilizing parallax can be performed.

[0510] The user can see the display on the display unit 8404 through the lens 8405. The lens 8405 has a focus adjustment mechanism that can adjust the position of the lens 8405 according to the user's vision. The display unit 8404 is preferably square or a horizontally elongated rectangle. This improves the realism.

[0511] The mounting part 8402 is preferably plastic and elastic so that it can be adjusted according to the user's face size without falling off. Additionally, a portion of the mounting part 8402 preferably has a vibration mechanism for use as a bone conduction headphone. Thus, simply installing it allows users to enjoy video and sound without the need for headphones, speakers, or other audio equipment. Furthermore, it can also have the function of wirelessly outputting audio data to the housing 8401.

[0512] The mounting part 8402 and the cushioning member 8403 are the parts that come into contact with the user's face (forehead, cheeks, etc.). By ensuring a close contact between the cushioning member 8403 and the user's face, light leakage can be prevented, thereby further enhancing the immersive experience. The cushioning member 8403 is preferably made of a soft material to ensure a close contact with the user's face when the user wears the head-mounted display 8400. For example, materials such as rubber, silicone rubber, polyurethane, and sponge can be used. Furthermore, when the cushioning member 8403 is made of a material that covers the surface of the sponge or similar material, such as cloth or leather (natural or synthetic leather), gaps are less likely to form between the user's face and the cushioning member 8403, thus effectively preventing light leakage. Additionally, using such materials not only provides a skin-friendly feel but also prevents the user from feeling cold when wearing the device, especially in colder seasons. It is also preferable that components in contact with the user's skin, such as the cushioning member 8403 and the mounting part 8402, have a detachable structure, making them easy to clean or replace.

[0513] The electronic devices shown in Figures 23A to 23F include a housing 9000, a display unit 9001, a speaker 9003, operation keys 9005 (including a power switch or operation switch), a connection terminal 9006, a sensor 9007 (which has the function of sensing, detecting or measuring factors such as force, displacement, position, velocity, acceleration, angular velocity, rotational speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, tilt, vibration, odor or infrared radiation), a microphone 9008, etc.

[0514] The electronic devices shown in Figures 23A to 23F have various functions. For example, they may have the following functions: displaying various information (still images, moving images, and text images, etc.) on a display unit; a touch panel function; displaying a calendar, date, or time; controlling processing using various software (programs); performing wireless communication; reading and processing programs or data stored in a storage medium; etc. Note that the functions of an electronic device are not limited to the above-mentioned functions, but can have a variety of functions. An electronic device may include multiple display units. Furthermore, a camera or similar device may be installed in the electronic device to enable it to have the following functions: capturing still or moving images and storing the captured images in a storage medium (external storage medium or storage medium built into the camera); displaying the captured images on a display unit; etc.

[0515] The display device according to one embodiment of the present invention can be used in the display unit 9001.

[0516] The electronic devices shown in Figures 23A to 23F will now be described in detail.

[0517] Figure 23A is a perspective view showing a portable information terminal 9101. The portable information terminal 9101 can be used, for example, as a smartphone. Note that a speaker 9003, a connection terminal 9006, a sensor 9007, etc., can also be provided in the portable information terminal 9101. Furthermore, as a portable information terminal 9101, text and image information can be displayed on multiple surfaces. Examples of three illustrations 9050 are shown in Figure 23A. Additionally, information 9051, shown as a dashed rectangle, can be displayed on other surfaces of the display unit 9001. Examples of information 9051 include notifications of received emails, SNS messages, or phone calls; email or SNS titles; sender's name; date; time; remaining battery level; and display of antenna signal strength. Alternatively, illustrations 9050 can be displayed in the same locations where information 9051 is displayed.

[0518] Figure 23B is a perspective view showing a portable information terminal 9102. The portable information terminal 9102 has the function of displaying information on three or more surfaces of the display unit 9001. Here, examples are shown where information 9052, information 9053, and information 9054 are displayed on different surfaces. For example, when the portable information terminal 9102 is placed in a jacket pocket, the user can check information 9053 displayed in a position seen from above the portable information terminal 9102. The user can check this display without taking the portable information terminal 9102 out of the pocket, thereby determining whether to answer a call.

[0519] Figure 23C is a perspective view showing a watch-type portable information terminal 9200. The portable information terminal 9200 can be used, for example, as a smartwatch (registered trademark). Furthermore, the display surface of the display unit 9001 is curved, allowing display along its curved surface. Additionally, the portable information terminal 9200 can perform hands-free calls, for example, by communicating with a headset capable of wireless communication. Furthermore, by utilizing the connection terminal 9006, the portable information terminal 9200 can transmit data and charge with other information terminals. Charging can also be performed wirelessly.

[0520] Figures 23D to 23F are perspective views showing the foldable portable information terminal 9201. Furthermore, Figure 23D is a perspective view of the portable information terminal 9201 in its unfolded state, Figure 23F is a perspective view of its folded state, and Figure 23E is a perspective view of the intermediate state during the transition from one of the states in Figures 23D and 23F to the other. The portable information terminal 9201 offers good portability in its folded state, and in its unfolded state, it provides a large, seamless display area, resulting in excellent browsing capabilities. The display unit 9001 included in the portable information terminal 9201 is supported by three housings 9000 connected by hinges 9055. The display unit 9001 can be bent, for example, within a radius of curvature of 0.1 mm or more and 150 mm or less.

[0521] At least a portion of the structural examples shown in this embodiment and the corresponding diagrams can be appropriately combined with other structural examples or diagrams.

[0522] At least a portion of this embodiment can be implemented in combination with other embodiments described in this specification.

[0523] Implementation Method 9 In this embodiment, the relationship between the screen size and pixel density of an electronic device equipped with an OLED display device and the technology that can be applied to the display device are explained.

[0524] Figure 24 is a graph showing the relationship between screen size and pixel density for a product. The horizontal axis represents screen size (inches), and the vertical axis represents pixel density (ppi). Figure 24 shows the typical range of screen sizes and pixel densities for products such as μOLED, smartphones, smartwatches, laptop PCs, tablets, automotive displays, display devices, and televisions (TVs) used in AR or VR products. It can be inferred that, generally, smaller screen sizes result in higher resolution.

[0525] Additionally, Figure 24 shows the technologies applicable to each product side-by-side. Here, BP represents the back panel, and FP represents the front panel.

[0526] Regarding the front panel, as a full-color technology for OLEDs, it can be roughly divided into separate coating technology using high-precision metal masks (FMM+SBS), separate coating technology using printing methods such as inkjet printing (printing+SBS), technology combining white OLED and color filter (W+CF), and technology combining blue OLED and quantum dot (B+Qd), etc.

[0527] In addition, as types of OLEDs, there are tandem structures with multiple light-emitting units stacked together and single structures without stacked light-emitting units.

[0528] As backplane manufacturing technologies, there are LSI technology using Si substrates, LTPS (Low Temperature Poly Silicon) technology, LTPO (Low Temperature Polysilicon and Oxide) technology, OS (Oxide Semiconductor) technology, etc.

[0529] Here, the technology of forming OLEDs using photolithography without a high-precision metal mask is referred to as MML (Metal Mask Less) technology. Compared with the aforementioned full-color technology, MML technology can achieve high aperture ratio, high efficiency, high brightness, high display quality, high contrast, and high reliability. MML technology can be applied to all display devices with the screen size and resolution shown in Figure 24. In particular, it can be applied to microdisplays with a screen size of about 1 inch and a resolution higher than 1000ppi.

[0530] Furthermore, the technique that combines a high-precision metal mask with photolithography is called HMML (Hybrid MML). HMML technology is a technology that can replace the conventional full-color technology using FMM+SBS and, compared with the full-color technology using FMM+SBS, can further achieve higher aperture ratio, higher reliability, higher display quality, and higher contrast.

[0531] At least a portion of this embodiment can be implemented in combination with other embodiments described in this specification.

[0532] 100: Display device 101:Substrate 103: pixels 105: Insulation layer 110B: Light-emitting element 110G: Light-emitting element 110R: Light-emitting element 110: Light-emitting element 111B: Pixel Electrode 111C: Connecting electrode 111G: Pixel Electrode 111R: Pixel Electrode 111: Pixel Electrode 112B: Organic layer 112G: Organic layer 112R: Organic layer 112: Organic layer 113: Common electrode 114: Organic layer 115: Organic layer 116: Organic layer 117: Charge Generation Layer 118: Organic layer 119: Organic layer 120: Slit 121: Protective layer 125a: pixels 125b: pixels 125f: Insulating film 125: Insulation layer 126: Resin layer 130: Connecting part 131: Insulation layer 132: Insulation layer 135B: Layer 135G: Layer 135R: Layer 143: Light Obscuration Mask 144: Sacrificial membrane 145: Sacrifice Layer 146: Sacrificial membrane 147: Sacrifice Layer 151B:FMM 151G:FMM 151R:FMM 161: Conductive layer 162: Conductive layer 163: Resin layer

Claims

1. A display device, comprising: First light-emitting element; The first light-emitting element comprises a first pixel electrode, a first light-emitting layer, and a common electrode stacked sequentially thereon. The second light-emitting element comprises a second pixel electrode, a second light-emitting layer, and the common electrode stacked sequentially thereon. The region between the first light-emitting element and the second light-emitting element includes a first layer and a second layer. The first layer overlaps with the second light-emitting layer and contains the same material as the first light-emitting layer. The second layer overlaps with the first light-emitting layer and contains the same material as the second light-emitting layer. In the region between the first light-emitting element and the second light-emitting element, the ends of the first light-emitting layer are opposite to the ends of the first layer. Furthermore, in the region between the first light-emitting element and the second light-emitting element, the ends of the second light-emitting layer are opposite to the ends of the second layer.

2. A display device, comprising: First light-emitting element; The system includes a first light-emitting element, wherein the first light-emitting element comprises a first pixel electrode, a first light-emitting layer, a first intermediate layer, a third light-emitting layer, and a common electrode stacked sequentially; the second light-emitting element comprises a second pixel electrode, a second light-emitting layer, a second intermediate layer, a fourth light-emitting layer, and the common electrode stacked sequentially; a first layer, a second layer, a third layer, and a fourth layer are included between the first and second light-emitting elements; the first layer overlaps with the second light-emitting layer, the second intermediate layer, and the fourth light-emitting layer and contains the same material as the first light-emitting layer; the second layer overlaps with the first light-emitting layer, the first intermediate layer, and the third light-emitting layer and contains the same material as the second light-emitting layer; the third layer overlaps with the first layer and contains the same material as the third light-emitting layer; and the fourth layer overlaps with the second layer and contains the same material as the fourth light-emitting layer; in the region between the first and second light-emitting elements, the ends of the first light-emitting layers are opposite to the ends of the first layers; and in the region between the first and second light-emitting elements, the ends of the second light-emitting layers are opposite to the ends of the second layers. In the region between the first light-emitting element and the second light-emitting element, the end of the third light-emitting layer is opposite to the end of the third layer, and in the region between the first light-emitting element and the second light-emitting element, the end of the fourth light-emitting layer is opposite to the end of the fourth layer.

3. The display device of claim 2, wherein the first light-emitting layer comprises the same material as the third light-emitting layer, and the second light-emitting layer comprises the same material as the fourth light-emitting layer.

4. The display device as described in claim 1 or 2 further includes: A resin layer, wherein in the region between the first light-emitting element and the second light-emitting element, the end of the first light-emitting layer faces the end of the first layer across the resin layer, and the end of the second light-emitting layer faces the end of the second layer across the resin layer.

5. The display device as described in claim 1 or 2 further includes: A first insulating layer is provided, wherein the first insulating layer is in the region between the first light-emitting element and the second light-emitting element, and the first insulating layer contacts the ends of the first light-emitting layer, the ends of the second light-emitting layer, the ends of the first layer, and the ends of the second layer.

6. A method for manufacturing a display device, comprising: A first process for arranging and forming a first pixel electrode and a second pixel electrode; A second process is used to form an island-shaped first light-emitting layer on the first pixel electrode using a first metal mask; a third process is used to form an island-shaped second light-emitting layer on the second pixel electrode using a second metal mask, wherein the second light-emitting layer overlaps the end of the first light-emitting layer; a fourth process is used to separate the first light-emitting layer and the second light-emitting layer respectively by etching in the region between the first pixel electrode and the second pixel electrode; and a fifth process is used to cover the first light-emitting layer and the second light-emitting layer to form a common electrode.

7. The method of manufacturing the display device as described in claim 6 further includes: A sixth process, which forms a resin layer within the slit created by the etching process, occurs between the fourth and fifth processes.

8. A method for manufacturing a display device as claimed in claim 7, wherein a photosensitive organic resin is used as the resin layer.

9. A method for manufacturing the display device as described in claim 7 or 8, comprising: A seventh process is performed between the fourth and sixth processes to form a first insulating layer by contacting the sides of the first light-emitting layer and the sides of the second light-emitting layer exposed by the etching.

10. A method for manufacturing a display device as claimed in claim 9, wherein an inorganic insulating film formed by atomic layer deposition is used as the first insulating layer.

Images