Display device and method for manufacturing the same

Abstract

Provided is a high-definition display device. Also provided is a display device having a high aperture ratio. The display device has a first light emitting element and a second light emitting element. In the first light emitting element, a first pixel electrode, a first light emitting layer, and a common electrode are stacked in this order. In the second light emitting element, a second pixel electrode, a second light emitting layer, and the common electrode are stacked in this order. A first layer and a second layer are provided in a region between the first light emitting element and the second light emitting element. The first layer overlaps the second light emitting layer, and includes the same material as the first light emitting layer. The second layer overlaps the first light emitting layer, and includes the same material as the second light emitting layer. In the region between the first light emitting element and the second light emitting element, an end portion of the first light emitting layer and an end portion of the first layer are provided facing one another. In the region between the first light emitting element and the second light emitting element, an end portion of the second light emitting layer and an end portion of the second layer are provided facing one another.

Description

[Technical Field]

[0001] FIELD OF THE INVENTION One embodiment of the present invention relates to a display device and a manufacturing method of the display device.

[0002] Note that one embodiment of the present invention is not limited to the above technical field. Examples of the technical field of one embodiment of the present invention disclosed in this specification and the like include semiconductor devices, display devices, light-emitting devices, power storage devices, memory devices, electronic devices, lighting devices, input devices, input / output devices, driving methods thereof, and manufacturing methods thereof. A semiconductor device refers to any device that can function by utilizing semiconductor characteristics. [Background technology]

[0003] In recent years, there has been a demand for higher definition display panels. Devices requiring high-definition display panels include, for example, smartphones, tablet devices, and notebook computers. Furthermore, with the trend toward higher resolution, stationary display devices such as televisions and monitors also require higher definition. Furthermore, devices requiring the highest definition include, for example, devices for virtual reality (VR) or augmented reality (AR).

[0004] Representative examples of display devices that can be applied to display panels include liquid crystal display devices, organic EL (Electro Luminescence) elements, light-emitting devices equipped with light-emitting elements such as light-emitting diodes (LEDs: Light Emitting Diodes), and electronic paper that displays using electrophoresis methods.

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

[0006] [Patent Document 1] International Publication No. 2018 / 087625 Summary of the Invention [Problem to be solved by the invention]

[0007] An object of one embodiment of the present invention is to provide a high-resolution display device.An object of one embodiment of the present invention is to provide a display device with a high aperture ratio.An object of one embodiment of the present invention is to provide a display device with high luminance.An object of one embodiment of the present invention is to provide a display device with high contrast.An object of one embodiment of the present invention is to provide a display device with high reliability.

[0008] An object of one embodiment of the present invention is to provide a display device having a novel structure.An object of one embodiment of the present invention is to provide a method for manufacturing a novel display device.An object of one embodiment of the present invention is to provide a method for manufacturing the above-described display device with high yield.An object of one embodiment of the present invention is to alleviate at least one of the problems of the prior art.

[0009] Note that the description of these problems does not preclude the existence of other problems. Note that one embodiment of the present invention does not necessarily solve all of these problems. Note that problems other than these can be extracted from the description of the specification, drawings, claims, etc. [Means for solving the problem]

[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 stacked in this order. The second light-emitting element has a second pixel electrode, a second light-emitting layer, and a common electrode stacked in this order. A first layer and a second layer are provided in a region between the first light-emitting element and the second light-emitting element. 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, an end of the first layer faces an end of the first layer. In the region between the first light-emitting element and the second light-emitting element, an end of the second light-emitting layer faces an end 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 includes a first pixel electrode, a first light-emitting layer, a first intermediate layer, a third light-emitting layer, and a common electrode stacked in this order. The second light-emitting element includes a second pixel electrode, a second light-emitting layer, a second intermediate layer, a fourth light-emitting layer, and a common electrode stacked in this order. A first layer, a second layer, a third layer, and a fourth layer are provided between the first light-emitting element and the second light-emitting element. 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. The fourth layer overlaps the second layer and contains the same material as the fourth light-emitting layer. In the region between the first light-emitting element and the second light-emitting element, an end of the first light-emitting layer faces an end of the first layer. In the region between the first light-emitting element and the second light-emitting element, an end of the second light-emitting layer faces an end of the second layer. In the region between the first light-emitting element and the second light-emitting element, an end of the third light-emitting layer faces an end of the third layer. In the region between the first light-emitting element and the second light-emitting element, an end of the fourth light-emitting layer faces an end of the fourth layer.

[0012] In the above, it is preferable that the first light-emitting layer and the third light-emitting layer contain the same material, and that the second light-emitting layer and the fourth light-emitting layer contain the same material.

[0013] In any of the above, it is preferable that a resin layer is provided. The resin layer is preferably located in a region between the first light-emitting element and the second light-emitting element. It is also preferable that an end of the first light-emitting layer and an end of the first layer face each other across the resin layer, and that an end of the second light-emitting layer and an end of the second layer face each other across the resin layer.

[0014] In any of the above, it is preferable that the device further comprises a first insulating layer, which is located in a region between the first light-emitting element and the second light-emitting element and is in contact with an end of the first light-emitting layer, an end of the second light-emitting layer, an end of the first layer, and an end of the second layer.

[0015] Another embodiment of the present invention is a method for manufacturing a display device, including: a first step of forming a first pixel electrode and a second pixel electrode side by side; a second step of forming an island-shaped first light-emitting layer over the first pixel electrode using a first metal mask; a third step of forming an island-shaped second light-emitting layer over the second pixel electrode using the second metal mask so as to overlap with an end portion of the first light-emitting layer; a fourth step of separating the first light-emitting layer and the second light-emitting layer by etching in a region between the first pixel electrode and the second pixel electrode; and a fifth step of forming a common electrode to cover the first light-emitting layer and the second light-emitting layer.

[0016] In the above method, it is preferable to have a sixth step of forming a resin layer in the slits formed by etching after the fourth step and before the fifth step.

[0017] In the above, it is preferable that the resin layer is made of a photosensitive organic resin.

[0018] In any of the above, it is preferable to have a seventh step, after the fourth step and before the sixth step, of forming a first insulating layer in contact with the side surfaces of the first light-emitting layer and the second light-emitting layer exposed by etching.

[0019] In the above, the first insulating layer is preferably an inorganic insulating film formed by atomic layer deposition. [Effects of the Invention]

[0020] According to one embodiment of the present invention, a high-resolution display device, a display device with a high aperture ratio, a display device with high luminance, a display device with high contrast, or a display device with high reliability can be provided.

[0021] According to one aspect of the present invention, a display device having a novel configuration can be provided. Alternatively, a method for manufacturing a novel display device can be provided. Alternatively, a method for manufacturing the above-described display device with high yield can be provided. According to one aspect of the present invention, at least one of the problems of the prior art can be alleviated.

[0022] Note that the description of these effects does not preclude the existence of other effects. Note that one embodiment of the present invention does not necessarily have all of these effects. Note that effects other than these can be extracted from the description in the specification, drawings, claims, etc. [Brief explanation of the drawings]

[0023] 1A to 1D are diagrams showing configuration examples of a display device. 2A to 2C are diagrams showing configuration examples of a display device. 3A and 3B are diagrams showing configuration examples of a display device. 4A and 4B are diagrams showing configuration examples of a display device. 5A and 5B are diagrams showing configuration examples of a display device. 6A and 6B are diagrams showing configuration examples of a display device. 7A and 7B are diagrams showing configuration examples of a display device. 8A to 8C are diagrams showing an example of a method for manufacturing a display device. 9A to 9C are diagrams showing an example of a method for manufacturing a display device. 10A to 10C are diagrams showing an example of a method for manufacturing a display device. 11A to 11C are diagrams showing an example of a method for manufacturing a display device. 12A to 12C are diagrams showing an example of a method for manufacturing a display device. FIG. 13 is a perspective view showing an example of a display device. 14A is a cross-sectional view illustrating an example of a display device, and FIG 14B is a cross-sectional view illustrating an example of a transistor. 15A to 15E are diagrams showing an example of a pixel of a display device. 16A to 16G are diagrams showing an example of a pixel of a display device. 17A to 17F are diagrams showing configuration examples of light-emitting devices. Figures 18A to 18D are diagrams showing an example of a pixel of a display device, and Figures 18E and 18F are diagrams showing an example of a circuit of a pixel of a display device. 19A to 19J are diagrams showing configuration examples of the display device. 20A and 20B are diagrams showing an example of an electronic device. 21A to 21D are diagrams showing an example of an electronic device. 22A to 22F are diagrams showing an example of an electronic device. 23A to 23F are diagrams showing an example of an electronic device. FIG. 24 is a diagram showing the relationship between product screen size and pixel density. DETAILED DESCRIPTION OF THE INVENTION

[0024] Hereinafter, embodiments will be described with reference to the drawings. However, it will be readily understood by those skilled in the art that the embodiments can be implemented in many different ways and that various changes in form and details can be made without departing from the spirit and scope of the present invention. Therefore, the present invention should not be interpreted as being limited to the following description of the embodiments.

[0025] In the configuration of the invention described below, the same parts or parts having similar functions are denoted by the same reference numerals in different drawings, and repeated explanations thereof will be omitted. In addition, when referring to similar functions, the same hatch pattern may be used and no particular reference numeral may be assigned.

[0026] In the drawings described in this specification, the size of each component, the thickness of a layer, or an area may be exaggerated for clarity, and therefore, the drawings are not necessarily limited to the scale.

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

[0028] Furthermore, in this specification and the like, the terms "film" and "layer" are interchangeable. For example, the terms "conductive layer" and "insulating layer" may be interchangeable with the terms "conductive film" and "insulating film."

[0029] In this specification, the EL layer refers to a layer provided between a pair of electrodes of a light-emitting element and containing at least a light-emitting substance (also referred to as a light-emitting layer), or a stack including a light-emitting layer.

[0030] In this specification and the like, a display panel, which is one aspect of a display device, has a function of displaying (outputting) images etc. on a display surface, and therefore the display panel is one aspect of an output device.

[0031] In addition, in this specification, a display panel having a connector such as an FPC (Flexible Printed Circuit) or TCP (Tape Carrier Package) attached to the substrate, or having an IC mounted on the substrate using a COG (Chip On Glass) method or the like, may be referred to as a display panel module, display module, or simply a display panel.

[0032] (Embodiment 1) In this embodiment, a structural example of a display device according to one embodiment of the present invention and an example of a manufacturing method of the display device will be described.

[0033] One embodiment of the present invention is a display device having a light-emitting element (also referred to as a light-emitting device). The display device has at least two light-emitting elements that emit different colors of light. Each light-emitting element has a pair of electrodes and an EL layer between them. The light-emitting element is preferably an organic EL element (organic electroluminescent element). Two or more light-emitting elements that emit different colors each have an EL layer containing a different material. For example, a full-color display device can be realized by having three types of light-emitting elements that emit red (R), green (G), or blue (B) light, respectively.

[0034] To create separate EL layers for light-emitting elements with different emission colors, a known method is to use a deposition method using a shadow mask such as a fine metal mask (FMM). However, this method can lead to deviations in the shape and position of the island-shaped organic film from the design due to various factors, such as the accuracy of the FMM, misalignment between the FMM and the substrate, deflection of the FMM, and the spread of the contours of the deposited film due to vapor scattering. This makes it difficult to achieve high resolution and a high aperture ratio for display devices. Therefore, measures have been taken to artificially increase resolution (also known as pixel density) by applying special pixel arrangements such as a pentile array.

[0035] In fabrication methods using FMM, two adjacent island-shaped organic films can be formed so that they partially overlap in order to achieve even slightly higher resolution and a higher aperture ratio. This significantly reduces the distance between the light-emitting regions compared to when the two island-shaped organic films are not overlapped. However, when two adjacent island-shaped organic films are formed overlapping each other, current leakage between the two adjacent light-emitting elements through the overlapping organic films can occur, resulting in unintended light emission. This can result in reduced brightness and contrast, degrading display quality. Furthermore, the leakage current can also reduce power efficiency and power consumption.

[0036] Therefore, in one embodiment of the present invention, organic films are separately formed between two adjacent light-emitting elements using FMM so that they partially overlap. Specifically, at least a layer containing a light-emitting organic compound (also referred to as a light-emitting layer) is separately formed using FMM. In this case, other organic films constituting the light-emitting element may be shared without being separately formed. An organic stacked film in which at least two types of light-emitting layers and other organic films are stacked is located in the region between the two adjacent light-emitting elements. Then, the organic stacked film is divided by etching the portion of the organic stacked film located between the two adjacent light-emitting elements using photolithography. This allows current leakage paths to be divided between the two adjacent light-emitting elements. This can increase brightness, contrast, power efficiency, or power consumption.

[0037] Furthermore, it is preferable to form an insulating layer to protect the side surfaces of the organic laminated film exposed by etching, thereby improving the reliability of the display device.

[0038] As described above, one embodiment of the present invention can realize a display device integrating minute light-emitting elements. For example, since there is no need to artificially increase the resolution by applying a special pixel arrangement method such as a pen tile method, a display device with a so-called stripe arrangement in which R, G, and B are arranged in one direction and a resolution of 300 ppi or more, 500 ppi or more, 700 ppi or more, or 1000 ppi or more can be realized. 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, but less than 100%, can be realized.

[0039] Furthermore, one embodiment of the present invention enables precise fabrication of minute light-emitting elements, which allows for the realization of complex pixel arrangements, such as not only a stripe arrangement but also various arrangements such as an S-stripe arrangement, a Bayer arrangement, and a delta arrangement.

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

[0041] Below, a more specific example of a structure and an example of a manufacturing method of a display device of one embodiment of the present invention will be described with reference to the drawings.

[0042] [Configuration example 1] 1A is a schematic top view of a display device 100 according to one embodiment of the present invention. The display device 100 includes a plurality of red light-emitting elements 110R, a plurality of green light-emitting elements 110G, and a plurality of blue light-emitting elements 110B. In FIG. 1A, the light-emitting regions of the light-emitting elements are labeled with R, G, and B to easily distinguish the light-emitting elements from one another.

[0043] The light-emitting elements 110R, 110G, and 110B are arranged in a matrix. Fig. 1A shows a so-called stripe arrangement in which light-emitting elements of the same color are arranged in one direction. Note that the arrangement of the light-emitting elements is not limited to this, and arrangements such as an S-stripe arrangement, a delta arrangement, a Bayer arrangement, or a zigzag arrangement may also be used, or a pentile arrangement may also be used.

[0044] The light emitting elements 110R, 110G, and 110B are arranged in the X direction. Furthermore, light emitting elements of the same color are arranged in the Y direction that intersects with the X direction.

[0045] As the light-emitting elements 110R, 110G, and 110B, it is preferable to use EL elements such as OLEDs (organic light-emitting diodes) or QLEDs (quantum-dot light-emitting diodes). Examples of light-emitting materials that the EL elements have include fluorescent materials, phosphorescent materials, and thermally activated delayed fluorescence (TADF materials). As the light-emitting materials that the EL elements have, not only organic compounds but also inorganic compounds (such as quantum dot materials) can be used.

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

[0047] FIG. 1B shows cross sections of light-emitting elements 110R, 110G, and 110B. Light-emitting element 110R has a pixel electrode 111R, an organic layer 115, an organic layer 112R, an organic layer 116, an organic layer 114, and a common electrode 113. Light-emitting element 110G has a pixel electrode 111G, an organic layer 115, an organic layer 112G, an organic layer 116, an organic layer 114, and a common electrode 113. Light-emitting element 110B has a pixel electrode 111B, an organic layer 115, an organic layer 112B, an organic layer 116, an organic layer 114, and a common electrode 113. The organic layer 114 and the common electrode 113 are provided in common to light-emitting elements 110R, 110G, and 110B. The organic layer 114 can also be referred to as 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. The organic layer 112R, the organic layer 112G, and the organic layer 112B can each be referred to as a light-emitting layer.

[0049] Hereinafter, when describing matters common to light emitting element 110R, light emitting element 110G, and light emitting element 110B, they may be referred to as light emitting element 110. Similarly, when describing matters common to components distinguished by alphabets, such as organic layer 112R, organic layer 112G, and organic layer 112B, they may be described using symbols without the alphabets.

[0050] In each light-emitting element, the laminated film located between the pixel electrode and the common electrode 113 can be called an EL layer.

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

[0052] The organic layer 115, the organic layer 116, and the organic layer 114 can each independently have one or more of an electron injection layer, an electron transport layer, a hole injection layer, and a hole transport layer. For example, the organic layer 115 can have a stacked structure of a hole injection layer and a hole transport layer from the pixel electrode 111 side, the organic layer 116 can have an electron transport layer, and the organic layer 114 can have an electron injection layer. Alternatively, the organic layer 115 can have a stacked structure of an electron injection layer and an electron transport layer from the pixel electrode 111 side, the organic layer 116 can have a hole transport layer, and the organic layer 114 can have a hole injection layer.

[0053] It should be noted that the term "organic layer" used for layers located between a pair of electrodes of a light-emitting element, such as organic layer 112, organic layer 114, organic layer 115, and organic layer 116, refers to layers that constitute an organic EL element, and does not necessarily need to contain an organic compound. For example, organic layer 112, organic layer 114, organic layer 115, and organic layer 116 may each be a film that does not contain an organic compound and contains only an inorganic compound or inorganic substance.

[0054] The pixel electrode 111R, pixel electrode 111G, and pixel electrode 111B are provided for each light-emitting element. The common electrode 113 and organic layer 114 are provided as a continuous layer common to each light-emitting element. A conductive film that is translucent to visible light is used for either the pixel electrode or the common electrode 113, and a conductive film that is reflective to visible light is used for the other. By making each pixel electrode translucent and the common electrode 113 reflective, a bottom-emission display device can be obtained. Conversely, by making each pixel electrode reflective and the common electrode 113 translucent, a top-emission display device can be obtained. Incidentally, by making both the pixel electrodes and the common electrode 113 translucent, a dual-emission display device can be obtained.

[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 a function of preventing impurities such as water from diffusing from above into each light emitting element.

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

[0057] The slit 120 is provided with an insulating layer 125 and a resin layer 126. The insulating layer 125 is provided along the sidewalls and bottom surface of the slit 120. The resin layer 126 is provided on the insulating layer 125 and functions to fill the recesses located in the slit 120 and flatten the upper surface. The resin layer 126 flattens the recesses of the slit 120, thereby improving the coverage of the organic layer 114, the common electrode 113, and the protective layer 121. The slit 120 can be formed simultaneously with the formation of openings for external connection terminals such as the connection electrode 111C, thereby eliminating the need for additional processes. The slit 120, which includes the insulating layer 125 and the resin layer 126, prevents short circuits between the pixel electrode 111 and the common electrode 113. The resin layer 126 also improves the adhesion of the organic layer 114. That is, by providing the resin layer 126, the adhesion of the organic layer 114 is improved, thereby suppressing peeling of the organic layer 114. Furthermore, since the insulating layer 125 is provided in contact with the side surface of an organic layer (e.g., the organic layer 115, etc.), a structure can be achieved in which the organic layer and the resin layer 126 do not come into contact with each other. If the organic layer comes into contact with the resin layer 126, the organic layer may be dissolved by an organic solvent 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, it is possible to protect the side surface of the organic layer. Note that the slit 120 may be configured to separate at least one or more of the hole injection layer, hole transport layer, electron blocking layer, light-emitting layer, hole blocking layer, electron transport layer, and electron injection layer.

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

[0059] In this specification and elsewhere, an oxynitride refers to a material whose composition contains more oxygen than nitrogen, and a nitride oxide refers to a material whose composition contains more nitrogen than oxygen. For example, silicon oxynitride refers to a material whose composition contains more oxygen than nitrogen, and silicon nitride oxide refers to a material whose composition contains more nitrogen than oxygen.

[0060] The insulating layer 125 can be formed by a sputtering method, a CVD method, a PLD method, an ALD method, etc. The insulating layer 125 is preferably formed by an ALD method, which has good coverage.

[0061] An insulating layer containing an organic material can be suitably used as the resin layer 126. For example, the resin layer 126 can be made of acrylic resin, polyimide resin, epoxy resin, imide resin, polyamide resin, polyimideamide resin, silicone resin, siloxane resin, benzocyclobutene-based resin, phenolic resin, or precursors of these resins. Alternatively, the resin layer 126 can be made of organic materials such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinylpyrrolidone, polyethylene glycol, polyglycerin, pullulan, water-soluble cellulose, or alcohol-soluble polyamide resin. Alternatively, the resin layer 126 can be made of a photosensitive resin. A photoresist can be used as the photosensitive resin. The photosensitive resin can be a positive-type material or a negative-type material. Alternatively, the resin layer 126 can be made of a colored material (e.g., a material containing a black pigment) to block stray light from adjacent pixels and suppress color mixing. In addition, a reflective film (for example, a metal film containing one or more selected from silver, palladium, copper, titanium, aluminum, etc.) may be provided between the insulating layer 125 and the resin layer 126, and the reflective film may reflect the light emitted from the light-emitting layer, thereby improving the light extraction efficiency.

[0062] The upper surface of the resin layer 126 is preferably as flat as possible, but may have a gently curved shape. While Fig. 1B and other figures show an example in which the upper surface of the resin layer 126 has a wavy shape with concave and convex portions, this is not limiting. For example, the upper surface of the resin layer 126 may be a convex surface, a concave surface, or a flat surface.

[0063] The protective layer 121 may also be a laminated film of an inorganic insulating film and an organic insulating film. For example, it is preferable to have a configuration in which an organic insulating film is sandwiched between a pair of inorganic insulating films. Furthermore, it is preferable that the organic insulating film functions as a planarizing film. This makes it possible to make the upper surface of the organic insulating film flat, thereby improving the coverage of the inorganic insulating film thereon and enhancing the barrier properties. In addition, since the upper surface of the protective layer 121 is flat, it is preferable that when a structure (e.g., a color filter, a touch sensor electrode, a lens array, etc.) is provided above the protective layer 121, the influence of uneven shapes caused by the structure below can be reduced.

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

[0065] 1C, slits 120 may be provided between light-emitting elements of the same color. In this way, by providing slits 120 between light-emitting elements of the same color, it is possible to preferably prevent current from flowing through two adjacent EL layers and causing unintended light emission. This makes it possible to improve contrast and realize a display device with high display quality.

[0066] In the Y direction, organic layer 112R, organic layer 112G, or organic layer 112B may be formed in a strip shape so that organic layer 112R, organic layer 112G, or organic layer 112B is continuous between light-emitting elements of the same color. By forming organic layer 112R, etc. in a strip shape, space to separate them is not required and the area of ​​the non-light-emitting region between light-emitting elements can be reduced, thereby increasing the aperture ratio.

[0067] 1A also shows a connection electrode 111C that is electrically connected to the common electrode 113. The connection electrode 111C is given a potential (for example, an anode potential or a cathode potential) to be supplied to the common electrode 113. The connection electrode 111C is provided outside the display area where the light-emitting elements 110R and the like are arranged. In addition, in FIG. 1A, the common electrode 113 is shown by a dashed line.

[0068] The connection electrodes 111C can be provided along the periphery of the display area. For example, they may be provided along one side of the periphery of the display area, or they may be provided over two or more sides of the periphery of the display area. That is, if the top surface of the display area has a rectangular shape, the top surface of the connection electrodes 111C can have a strip-like, L-shaped, U-shaped (square bracket-shaped), quadrangular, or the like shape.

[0069] Fig. 1D is a schematic cross-sectional view corresponding to dashed dotted line C1-C2 in Fig. 1A. Fig. 1D shows a connection portion 130 where the connection electrode 111C and the common electrode 113 are electrically connected. In the connection portion 130, the common electrode 113 is provided on the connection electrode 111C with an organic layer 114 interposed therebetween. 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] The organic layer 114 does not necessarily have to be provided in the connection section 130. In that case, in the connection section 130, the common electrode 113 is provided in contact with the connection electrode 111C, and the protective layer 121 is provided to cover the common electrode 113.

[0071] 2A, 2B, and 2C show an example in which the insulating layer 125 is not provided.

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

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

[0074] As shown in Fig. 3A, the edge of the pixel electrode 111 is preferably tapered. This can improve the step coverage of the organic layer 115, etc. In this specification and the like, a tapered edge of an object means that the angle between the surface and the surface to be formed in the edge region is greater than 0 degrees and less than 90 degrees, and the cross-sectional shape has a continuously increasing thickness from the edge. Note that although the pixel electrode 111R and the like have a single-layer structure here, multiple layers may be stacked.

[0075] An organic layer 115 is provided to cover the pixel electrode 111R. An organic layer 115 is also provided to cover the pixel electrode 111G. These organic layers 115 are formed by dividing a continuous film by a slit 120.

[0076] On the light emitting element 110R side of the slit 120, organic layer 112R is provided covering organic layer 115. Furthermore, on the light emitting element 110G side of the slit 120, layer 135R is provided on organic layer 115. Layer 135R can also be said to be a fragment of a part of the film that will become organic layer 112R, which is separated by slit 120 and remains on the light emitting element 110G side.

[0077] Furthermore, organic layer 112G is provided covering organic layer 115 on the light emitting element 110G side of slit 120. Furthermore, layer 135G is provided on organic layer 112R on the light emitting element 110R side of slit 120. Layer 135G can also be said to be a fragment of a part of the film that will become organic layer 112G, which is separated by slit 120 and remains on the light emitting element 110R side.

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

[0079] An organic layer 116 is provided to cover organic layer 112R and layer 135G. An organic layer 116 is also provided to cover organic layer 112G and layer 135R. Similar to organic layer 115, these organic layers 116 are formed by dividing a continuous film by slits 120.

[0080] Insulating layer 125 is provided inside slit 120 and in contact with the side surfaces of pair of organic layers 115, organic layer 112R, organic layer 112G, layer 135R, layer 135G, and pair of organic layers 116. Insulating layer 125 is also provided to cover the upper surface of substrate 101.

[0081] The resin layer 126 is provided in contact with the upper surface and side surfaces of the insulating layer 125. The resin layer 126 has the function of flattening recesses in the surface on which the organic layer 114 is to be formed.

[0082] An organic layer 114, a common electrode 113, and a protective layer 121 are formed in this order to cover the top surfaces of the organic layer 116, the insulating layer 125, and the resin layer 126. The organic layer 114 may not be provided if it is not necessary.

[0083] Here, layers 135R and 135G are portions located at the edges of the film that will become organic layer 112R or organic layer 112G. In a film formation method using FMM, the thickness of an organic film tends to gradually decrease toward the edges, so layers 135R and 135G have portions that are thinner than organic layer 112R or organic layer 112G. Layers 135R and 135G may be so thin that they cannot be confirmed by cross-sectional observation. Furthermore, even if layer 135R or layer 135G exists, it may be difficult to confirm the boundary between layer 135R and organic layer 112G and the boundary between layer 135G and organic layer 112R by cross-sectional observation.

[0084] On the other hand, layers 135R and 135G contain luminescent compounds (e.g., fluorescent materials, phosphorescent materials, quantum dots, etc.). Therefore, when irradiated with ultraviolet light or visible light, photoluminescence is observed in a planar view. Observing this luminescence with an optical microscope or the like can confirm the presence of layers 135R and 135G. Specifically, layer 135R and organic layer 112G overlap in the area where layer 135R is located. Therefore, when ultraviolet light or the like is irradiated onto this area, both light from layer 135R and organic layer 112G are observed. Furthermore, based on the emission spectrum, wavelength, emission color, etc. of the light emitted from layers 135R and 135G, it can be confirmed that layer 135R or layer 135G contains the same material as organic layer 112R or organic layer 112G. Furthermore, it may also be possible to estimate the compounds contained in layers 135R and 135G.

[0085] Here, an example has been shown in which organic layer 112R and organic layer 112G are separately formed using FMM, and the other organic layers (organic layer 115, organic layer 116) are formed as a continuous film, but this is not limiting. For example, either organic layer 115, organic layer 116, or both may also be separately formed using FMM. In this case, pieces of organic layer 115 or organic layer 116 may remain near slit 120, similar to layer 135R and the like.

[0086] 3B is a schematic cross-sectional view without insulating layer 125. Resin layer 126 is provided in contact with the side surfaces of the pair of organic layers 115, the side surfaces of organic layer 112R, the side surfaces of organic layer 112G, the side surfaces of layer 135R, the side surfaces of layer 135G, and the side surfaces of the pair of organic layers 116.

[0087] At this time, a part of the EL layer may be dissolved by the solvent used in forming the film that becomes the resin layer 126. Therefore, when the insulating layer 125 is not provided, it is preferable to use water or an alcohol such as ethyl alcohol, methyl alcohol, isopropyl alcohol (IPA), or glycerin as the solvent for the resin layer 126. However, the solvent is not limited to this, and any solvent that does not dissolve or hardly dissolves the EL layer may be used.

[0088] In the enlarged views shown in Figures 3A and 3B, light-emitting element 110R, light-emitting element 110G, and the area between them are described, but the area between light-emitting element 110R and light-emitting element 110B, and the area between light-emitting element 110G and light-emitting element 110B also have a similar configuration.

[0089] [Configuration example 2] By stacking multiple light-emitting layers, it is possible to obtain light emission with higher brightness when the same current is applied compared to when a single light-emitting layer is used. Furthermore, the current density required to obtain the same brightness can be reduced, thereby improving reliability. Below, an example of stacking light-emitting layers will be described.

[0090] Fig. 4A shows a schematic cross-sectional view of a display device exemplified below. The display device has a light-emitting element 110R, a light-emitting element 110G, and a light-emitting element 110B. The light-emitting element 110R, the light-emitting element 110G, and the light-emitting element 110B shown in Fig. 4A are light-emitting elements having a so-called tandem structure in which two light-emitting layers are stacked with a charge generation layer (also referred to as an intermediate layer) interposed therebetween.

[0091] The light-emitting element 110R has a configuration in which organic layers 115, 112R1, 116, charge generation layers 117, 118, 112R2, 119, 114, and a common electrode 113 are stacked on a pixel electrode 111R. Similarly, the light-emitting element 110G has a pixel electrode 111G, organic layers 115, 112G1, 116, charge generation layers 117, 118, 112G2, 119, 114, and a common electrode 113. The light-emitting element 110B has a pixel electrode 111B, organic layers 115, 112B1, 116, charge generation layers 117, 118, 112B2, 119, 114, and a common electrode 113.

[0092] A slit 120 is provided between two adjacent light-emitting elements. The slit 120 is formed so as to divide the laminated structure from the organic layer 115 to the organic layer 119 provided in the region between the two pixel electrodes. Furthermore, an insulating layer 125 and a resin layer 126 are provided inside the slit 120. Note that the insulating layer 125 may not be provided.

[0093] FIG. 4B is a schematic cross-sectional view including a part of light-emitting element 110R, a part of light-emitting element 110G, and the region therebetween in FIG. 4A.

[0094] On the light emitting element 110R side of the slit 120, a layer 135G1 is provided between the organic layer 115 and the organic layer 116. Furthermore, a layer 135G2 is provided between the organic layer 118 and the organic layer 119.

[0095] On the light emitting element 110G side of the slit 120, a layer 135R1 is provided between the organic layer 115 and the organic layer 116. Furthermore, a layer 135R2 is provided between the organic layer 118 and the organic layer 119.

[0096] Layers 135R1 and 135R2 can be considered to be fragments remaining on the light-emitting element 110G side of a portion of the film that will become organic layer 112R1 or organic layer 112R2, respectively, after being separated by slit 120. Similarly, layers 135G1 and 135G2 can be considered to be fragments remaining on the light-emitting element 110R side of a portion of the film that will become organic layer 112G1 or organic layer 112G2, respectively, after being separated by slit 120.

[0097] The side surface of the layer 135R1 and the side surface of the organic layer 112R1 are arranged to face each other with the resin layer 126 (and the insulating layer 125) interposed therebetween. Similarly, the side surfaces of the layer 135R2 and the organic layer 112R2, the layer 135G1 and the organic layer 112G1, and the layer 135G2 and the organic layer 112G2 are arranged to face each other with the resin layer 126 (and the insulating layer 125) interposed therebetween.

[0098] Note that one or more of the layers 135R1, 135R2, 135G1, and 135G2 may not be provided.

[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 are the same as the stacking order of organic layer 112R1 and organic layer 112G1 or the stacking order of organic layer 112R2 and organic layer 112G2, respectively, and the order is not important.

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

[0101] The stacked structure from organic layer 115 to organic layer 116 and the stacked structure from organic layer 118 to organic layer 114 can each be called one light-emitting unit. Light-emitting element 110 shown in FIG. 4A and other figures can be called a light-emitting element having a tandem structure in which two light-emitting units are stacked with charge generation layer 117 interposed therebetween.

[0102] [Variations] Fig. 5A is a modification of Fig. 3A, showing an example in which an insulating layer 131 is provided to cover the edge of the pixel electrode.

[0103] The insulating layer 131 has a function of planarizing the surface on which the organic layer 115 is formed. The end of the insulating layer 131 is preferably tapered. Furthermore, by using an organic resin for the insulating layer 131, the surface can be made gently curved. This improves the coverage of the film formed on the insulating layer 131.

[0104] Materials that can be used for the insulating layer 131 include, for example, acrylic resin, polyimide resin, epoxy resin, polyamide resin, polyimideamide resin, siloxane resin, benzocyclobutene resin, phenol resin, and precursors of these resins.

[0105] 5A, insulating layer 131 may have a recess in the region overlapping with slit 120. This recess can be formed by etching a part of the upper part of insulating layer 131 during etching to form slit 120. A part of insulating layer 125 is formed so as to fit into the recess of insulating layer 131, thereby improving adhesion therebetween.

[0106] The slit 120 is provided in a region overlapping with the insulating layer 131. The layer 135R and the layer 135G are also provided in a region overlapping with the insulating layer 131.

[0107] FIG. 5B shows an example in which an insulating layer 131 is applied to the above-mentioned FIG. 4B.

[0108] In FIG. 5B, the slit 120, the layer 135R1, the layer 135R2, the layer 135G1, and the layer 135G2 are provided in the regions overlapping with the insulating layer 131, respectively.

[0109] 6A and 6B show an example in which an insulating layer 132 is provided on an insulating layer 131. In FIG.

[0110] The insulating layer 132 overlaps with an end portion of the pixel electrode 111 with the insulating layer 131 interposed therebetween. The insulating layer 132 is provided to cover the end portion of the insulating layer 131. The insulating layer 132 has a portion in contact with the upper surface of the pixel electrode 111.

[0111] The insulating layer 132 preferably has tapered edges, which can improve the step coverage of films formed on the insulating layer 132, such as an EL layer provided to cover the edges of the insulating layer 132.

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

[0113] Examples of inorganic insulating materials that can be used for the insulating layer 132 include oxides and nitrides such as silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, aluminum oxide, aluminum oxynitride, and hafnium oxide. In addition, yttrium oxide, zirconium oxide, gallium oxide, tantalum oxide, magnesium oxide, lanthanum oxide, cerium oxide, neodymium oxide, and the like may also be used.

[0114] The insulating layer 132 may also be formed by stacking films containing the above inorganic insulating materials. For example, the insulating layer 132 may have a stacked structure in which a silicon oxide film or a silicon oxynitride film is stacked on a silicon nitride film, or a stacked structure in which a silicon oxide film or a silicon oxynitride film is stacked on an aluminum oxide film. Silicon oxide films and silicon oxynitride films are particularly resistant to etching, and therefore are preferably disposed on the upper side. Furthermore, silicon nitride films and aluminum oxide films are films through which water, hydrogen, oxygen, and the like do not easily diffuse. Therefore, by disposing the silicon nitride film and aluminum oxide film on the insulating layer 131 side, they function as a barrier layer that prevents gases desorbed from the insulating layer 131 from diffusing into the light-emitting element.

[0115] The slit 120 is provided in a region overlapping with the insulating layer 132. The layer 135R and the layer 135G are also provided in a region overlapping with the insulating layer 132.

[0116] By providing the insulating layer 132, it is possible to prevent the upper surface of the insulating layer 131 from being etched when the slits 120 are formed.

[0117] FIG. 6B shows an example in which an insulating layer 132 is applied to the above-mentioned FIG. 5B.

[0118] In FIG. 6B, the slit 120, the layer 135R1, the layer 135R2, the layer 135G1, and the layer 135G2 are provided in the areas overlapping with the insulating layer 132, respectively.

[0119] [Configuration example 3] A more specific configuration example will be described below.

[0120] Fig. 7A is a schematic cross-sectional view of a display device exemplified below. Fig. 7A shows a cross section of a region including light-emitting element 110R, light-emitting element 110G, light-emitting element 110B, and connecting portion 130. Fig. 7B is an enlarged schematic cross-sectional view of slit 120 located between light-emitting element 110R and light-emitting element 110G and its vicinity.

[0121] In the configuration shown in FIG. 7A, a layer 135B, which is a part (piece) of the organic layer 112B separated by the slit 120, is provided near the light emitting element 110R and near the light emitting element 110G.

[0122] Below the pixel electrode 111, a conductive layer 161, a conductive layer 162, and a resin layer 163 are provided.

[0123] The conductive layer 161 is provided over the insulating layer 105. The conductive layer 161 has a portion that penetrates the insulating layer 105 in an opening provided in the insulating layer 105. The conductive layer 161 functions as a wiring or an electrode that electrically connects a wiring, a transistor, an electrode, or the like (not shown) located below the insulating layer 105 to the pixel electrode 111.

[0124] A recess is formed in the conductive layer 161 at a portion corresponding to the opening of the insulating layer 105. The resin layer 163 is provided to fill the recess and functions as a planarizing film. The flatter the upper surface of the resin layer 163, the better, but it may also have a gently curved shape. While FIG. 7A and other figures show an example in which the upper surface of the resin layer 163 has a wave-like shape with recesses and protrusions, this is not limiting. For example, the upper surface of the resin layer 163 may be a convex surface, a concave surface, or a flat surface.

[0125] A conductive layer 162 is provided over the conductive layer 161 and the resin layer 163. The conductive layer 162 functions as an electrode that electrically connects the conductive layer 161 and the pixel electrode 111.

[0126] Here, when the light-emitting element 110 is a top-emission light-emitting element, a film reflective to visible light is used for the conductive layer 162, and a film transparent to visible light is used for the pixel electrode 111R, so that the conductive layer 162 can function as a reflective electrode. Furthermore, the conductive layer 162 and the pixel electrode 111 can be provided above the opening (also referred to as a contact portion) of the insulating layer 105 with the resin layer 163 interposed therebetween, so that the portion overlapping with the contact portion can be used as a light-emitting region. Therefore, the aperture ratio can be increased.

[0127] 7A and 7B show an example in which the shape of the resin layer 126 is different from that described above.

[0128] As shown in FIG. 7B , the upper part of the resin layer 126 has a shape that is wider than the slits 120. As will be described later, the insulating layer 125 is processed using the resin layer 126 as an etching mask, so a portion of the insulating layer 125 that is covered by the upper part 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 slits 120. Furthermore, a portion of the insulating layer 125 is provided so as to cover the upper surface of the sacrificial layer 145. Furthermore, the resin layer 126 is provided so as to cover the sacrificial layer 145 and the insulating layer 125.

[0129] In this case, it is preferable that the end of the insulating layer 125 and the end of the sacrificial layer 145 each have a tapered shape, which can improve the step coverage of the organic layer 114 and the like.

[0130] As shown in FIGS. 7A and 7B, the layer 135R, the layer 135G, and the layer 135B are in contact with the insulating layer 125 and have regions overlapping with the insulating layer 125, the sacrificial layer 145, and the resin layer 126, respectively.

[0131] [Example of manufacturing method] An example of a method for manufacturing a display device according to one embodiment of the present invention will be described below with reference to the drawings. Here, the display device shown in FIG. 7A will be used as an example. FIGS. 8A to 11C are cross-sectional schematic views illustrating steps in an example of a method for manufacturing a display device, which will be described below. Also, in FIG. 8A and other drawings, cross-sectional schematic views of the connection portion 130 and its vicinity are also shown on the right side.

[0132] The thin films (insulating films, semiconductor films, conductive films, etc.) that make up the display device 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. Metal organic chemical vapor deposition (MOCVD) is one type of thermal CVD.

[0133] Furthermore, thin films (insulating films, semiconductor films, conductive films, etc.) that constitute the display device can be formed by methods such as spin coating, dipping, spray coating, inkjet, dispensing, screen printing, offset printing, doctor knife method, slit coating, roll coating, curtain coating, and knife coating.

[0134] Furthermore, when processing the thin film that constitutes the display device, a photolithography method or the like can be used. Alternatively, the thin film may be processed by a nanoimprint method, a sandblasting method, a lift-off method, or the like. Furthermore, the island-shaped thin film may be directly formed by a film formation method using a shielding mask such as a metal mask.

[0135] There are two typical photolithography methods: one is to form a resist mask on the thin film to be processed, process the thin film by etching or the like, and then remove the resist mask; the other is to form a photosensitive thin film, and then process the thin film into the desired shape by exposure and development.

[0136] In photolithography, the light used for exposure can be, for example, i-line (wavelength 365 nm), g-line (wavelength 436 nm), h-line (wavelength 405 nm), or a mixture of these. Other light sources that can be used include ultraviolet light, KrF laser light, and ArF laser light. Exposure can also be performed using immersion exposure technology. Light sources that can be used for exposure include extreme ultraviolet (EUV) light, X-rays, and the like. Electron beams can also be used instead of light for exposure. Extreme ultraviolet light, X-rays, or electron beams are preferred because they enable extremely fine processing. When exposure is performed by scanning a beam such as an electron beam, a photomask is not required.

[0137] For etching the thin film, dry etching, wet etching, sandblasting, or the like can be used.

[0138] [Preparation of Substrate 101] A substrate having heat resistance sufficient to withstand at least a subsequent heat treatment can be used as the substrate 101. When an insulating substrate is used as the substrate 101, a glass substrate, a quartz substrate, a sapphire substrate, a ceramic substrate, an organic resin substrate, or the like can be used. Also, a semiconductor substrate such as a single crystal semiconductor substrate made of silicon, silicon carbide, or the like, a polycrystalline semiconductor substrate, a compound semiconductor substrate such as silicon germanium, or an SOI substrate can be used.

[0139] In particular, it is preferable to use a substrate in which a semiconductor circuit including semiconductor elements such as transistors is formed on the semiconductor substrate or insulating substrate as the substrate 101. The semiconductor circuit preferably constitutes, for example, a pixel circuit, a gate line driving circuit (gate driver), a source line driving circuit (source driver), etc. In addition to the above, an arithmetic circuit, a memory circuit, etc. may also be configured.

[0140] An insulating layer 105 is provided on the top of the substrate 101. A plurality of openings are provided in the insulating layer 105, which reach transistors, wirings, electrodes, and the like provided on the substrate 101. The openings can be formed by photolithography.

[0141] The insulating layer 105 can be made of an inorganic insulating material or an organic insulating material.

[0142] [Formation of the Conductive Layer 161, Resin Layer 163, Conductive Layer 162, and Pixel Electrode 111] A conductive film that will become the conductive layer 161 is formed on the insulating layer 105. At this time, due to the opening in the insulating layer 105, a recess is formed in the conductive film.

[0143] Subsequently, a resin layer 163 is formed in the recesses of the conductive film.

[0144] It is preferable to use a photosensitive resin as the resin layer 163. In this case, a resin film is first formed, and then the resin film is exposed to light through a photomask, followed by a development process, thereby forming the resin layer 163. Thereafter, in order to adjust the height of the upper surface of the resin layer 163, the upper part of the resin layer 163 may be etched by ashing or the like.

[0145] Furthermore, when a non-photosensitive resin is used as the resin layer 163, after forming the resin film, the upper part of the resin film is etched by ashing or the like until the surface of the conductive film that will become the conductive layer 161 is exposed so that the thickness is optimized, thereby forming the resin layer 163.

[0146] Next, a conductive film that becomes the conductive layer 161 and a conductive film that becomes the conductive layer 162 are formed over the resin layer 163. After that, a resist mask is formed over the two conductive film layers by photolithography, and unnecessary portions of the conductive film are removed by etching. After that, the resist mask is removed, so that the conductive layer 161 and the conductive layer 162 can be formed in the same process.

[0147] Note that although the conductive layers 161 and 162 are formed in the same step using the same photomask here, the conductive layers 161 and 162 may be formed separately using different photomasks.

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

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

[0150] The organic layer 115 may be separately formed using FMM. In this case, the description of the organic layer 112R and the like to be described later can be applied.

[0151] The organic layer 115 can be preferably formed by a vacuum deposition method. However, it is not limited to this, and it can also be formed by a sputtering method, an inkjet method, or the like. However, it is not limited to this, and the above-mentioned film formation methods can be used appropriately.

[0152] [Formation of Organic Layer 112R, Organic Layer 112G, and Organic Layer 112B] Subsequently, an island-shaped organic layer 112R is formed on the organic layer 115 so as to encompass the region overlapping with the pixel electrode 111R.

[0153] The organic layer 112R is preferably formed by vacuum deposition using an FMM. Alternatively, the island-shaped organic layer 112R may be formed by sputtering using an FMM or by inkjet printing.

[0154] 8C shows the organic layer 112R being deposited via the FMM 151R by a so-called face-down method, in which the substrate is inverted so that the surface to be deposited faces downward.

[0155] In evaporation methods using an FMM, evaporation is often performed over an area wider than the opening pattern of the FMM. Therefore, as shown by the dashed line in Figure 8C, even when an FMM 151R with the same opening pattern as the pixel electrode 111R is used, the organic layer 112R can be deposited up to the area between the pixel electrode 111R and the adjacent pixel electrode.

[0156] Subsequently, an organic layer 112G is formed on the pixel electrode 111G using an FMM 151G (FIG. 9A).

[0157] Similar to the organic layer 112R, the organic layer 112G can be formed in a pattern that extends beyond the pixel electrode 111G. As a result, as shown in region RG in FIG. 9A, a portion where the organic layer 112G is stacked on the organic layer 112R can be formed.

[0158] Subsequently, the organic layer 112B is formed on the pixel electrode 111B using the FMM 151B (FIG. 9B).

[0159] Similar to the organic layers 112R and 112G, the organic layer 112B may also be formed with a pattern that extends outward from the pixel electrode 111B. As a result, as shown in Fig. 9B, a region RB where the organic layer 112B is stacked on the organic layer 112R, and a region GB where the organic layer 112B is stacked on the organic layer 112G may be formed.

[0160] Here, it is preferable that the organic layer 112R, the organic layer 112G, and the organic layer 112B are not formed on the connection electrode 111C.

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

[0162] [Formation of organic layer 116] Subsequently, organic layer 116 is formed to cover organic layer 112R, organic layer 112G, and organic layer 112B (FIG. 9C). Organic layer 116 can be formed by the same method as organic layer 115.

[0163] [Formation of Sacrificial Film 144] Subsequently, a sacrificial film 144 is formed covering the organic layer 116 .

[0164] For the sacrificial film 144, a film that is highly resistant to the etching process of the organic layers 115, 112, and 116, i.e., a film with a large etching selectivity, can be used. Also, for the sacrificial film 144, a film that has a large etching selectivity with respect to a sacrificial film such as the sacrificial film 146 described below can be used. Furthermore, for the sacrificial film 144, it is particularly preferable to use a film that can be removed by wet etching, which causes little damage to the organic layers 115, 112, and 116.

[0165] For example, an inorganic film such as a metal film, an alloy film, a metal oxide film, a semiconductor film, or an inorganic insulating film can be suitably used as the sacrificial film 144. The sacrificial film 144 can be formed by various film formation methods such as a sputtering method, a vapor deposition method, a CVD method, or an ALD method.

[0166] In particular, since the ALD method causes less damage to the layer on which the film is formed, it is preferable to form the sacrificial film 144 directly on the organic layer 116 using the ALD method.

[0167] For example, metal materials such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, titanium, aluminum, yttrium, zirconium, and tantalum, or alloy materials containing these metal materials can be used as the sacrificial film 144. In particular, it is preferable to use a low-melting-point material such as aluminum or silver.

[0168] Furthermore, metal oxides such as indium gallium zinc oxide (In-Ga-Zn oxide, also written as IGZO) can be used for 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), indium gallium tin zinc oxide (In-Ga-Sn-Zn oxide), etc. can also be used. Alternatively, indium tin oxide containing silicon can also be used.

[0169] The present invention can also be applied to a case where, instead of the gallium, an element M (wherein M is one or more elements selected from aluminum, silicon, boron, yttrium, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, and magnesium) is used. In particular, it is preferable that M is one or more elements selected from gallium, aluminum, and yttrium.

[0170] Furthermore, oxides such as aluminum oxide, hafnium oxide, and silicon oxide, nitrides such as silicon nitride and aluminum nitride, and oxynitrides such as silicon oxynitride can be used as the sacrificial film 144. Such inorganic insulating materials can be formed using a film formation method such as a sputtering method, a CVD method, or an ALD method.

[0171] Furthermore, the sacrificial film 144 may be made of a material that is soluble in a chemically stable solvent, at least with respect to the organic layer 116 located at the top of the EL layer. In particular, a material that dissolves in water or alcohol is preferably used for the sacrificial film 144. When forming the sacrificial film 144, it is preferable to apply the material dissolved in a solvent such as water or alcohol by a wet film formation method, and then perform a heat treatment to evaporate the solvent. At this time, performing the heat treatment under a reduced pressure atmosphere is preferable because it allows the solvent to be removed at a low temperature in a short time, thereby reducing thermal damage to the EL layer.

[0172] Wet film formation methods that can be used to form the sacrificial film 144 include spin coating, dipping, spray coating, inkjet, dispensing, screen printing, offset printing, doctor knife method, slit coating, roll coating, curtain coating, and knife coating.

[0173] The sacrificial film 144 can be made of an organic material such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinyl pyrrolidone, polyethylene glycol, polyglycerin, pullulan, water-soluble cellulose, or alcohol-soluble polyamide resin.

[0174] [Formation of Sacrificial Film 146] Subsequently, a sacrificial film 146 is formed on the sacrificial film 144 .

[0175] The sacrificial film 146 is a film that is used as a hard mask when etching the sacrificial film 144 later. Furthermore, when processing the sacrificial film 146 later, the sacrificial film 144 is exposed. Therefore, a combination of films that have a large etching selectivity with respect to each other is selected for the sacrificial film 144 and the sacrificial film 146. Therefore, a film that can be used for the sacrificial film 146 can be selected depending on the etching conditions for the sacrificial film 144 and the etching conditions for 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 etching conditions of the sacrificial film 146. For example, the material can be selected from the films that can be used for the sacrificial film 144 described above.

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

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

[0179] For example, it is preferable to use an inorganic insulating material such as aluminum oxide, hafnium oxide, or silicon oxide formed by an ALD method as the sacrificial film 144, and a metal oxide containing indium such as indium gallium zinc oxide (In-Ga-Zn oxide, also referred to as IGZO) formed by a sputtering method as the sacrificial film 146. Alternatively, it is preferable to use a metal such as tungsten, molybdenum, copper, aluminum, titanium, or tantalum, or an alloy containing such a metal as the sacrificial film 146.

[0180] Alternatively, the sacrificial film 146 may be an organic film that can be used for the organic layer 115, the organic layer 112, the organic layer 116, and the like. For example, the same organic film as that used for the organic layer 115, the organic layer 112, and the organic layer 116 can be used for the sacrificial film 146. Using such an organic film is preferable because it allows the same film-forming equipment to be used for the organic layer 115, the organic layer 112, the organic layer 116, and the like. Furthermore, the sacrificial layer 147 can be removed at the same time as etching the organic layer 115, the organic layer 112, the organic layer 116, and the like later using the sacrificial layer 147 as a mask, thereby simplifying the process.

[0181] [Formation of Resist Mask 143] Subsequently, a resist mask 143 is formed on the sacrificial film 146 at positions overlapping the pixel electrode 111R, the pixel electrode 111G, and the pixel electrode 111B (FIG. 10A).

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

[0183] Here, if the resist mask 143 is formed on the sacrificial film 144 without the sacrificial film 146, and defects such as pinholes exist in the sacrificial film 144, the organic layer 115, the organic layer 112, the organic layer 116, etc. may be dissolved by the solvent of the resist material. By using the sacrificial film 146, it is possible to prevent such defects from occurring.

[0184] In addition, when a material that does not dissolve the organic layer 115, the organic layer 112, and the organic layer 116 is used as a solvent for the resist material, it may be possible to form the resist mask 143 directly on the sacrificial film 144 without using the sacrificial film 146.

[0185] [Etching of the sacrificial film 146] Subsequently, a portion of the sacrificial film 146 that is not covered by the resist mask 143 is removed by etching to form a sacrificial layer 147 .

[0186] When etching the sacrificial film 146, it is preferable to use etching conditions with a high selectivity so that the sacrificial film 144 is not removed by the etching. The sacrificial film 146 can be etched by wet etching or dry etching, but by using dry etching, it is possible to prevent the pattern of the sacrificial layer 147 from shrinking.

[0187] [Removal of resist mask 143] Subsequently, the resist mask 143 is removed.

[0188] The resist mask 143 can be removed by wet etching or dry etching. In particular, it is preferable to remove the resist mask 143 by dry etching (also called plasma ashing) using oxygen gas as an etching gas.

[0189] At this time, the resist mask 143 is removed in a state in which the organic layer 116 is covered with the sacrificial film 144, and therefore the effect on the organic layer 115, the organic layer 112, and the organic layer 116 is suppressed. In particular, if the organic layer 115, the organic layer 112, and the organic layer 116 come into contact with oxygen, it may have an adverse effect on the electrical characteristics, and therefore this is suitable for performing etching using oxygen gas, such as plasma ashing. Furthermore, even when the resist mask 143 is removed by wet etching, the organic layer 116 and the like do not come into contact with the chemical solution, and therefore dissolution of the organic layer 116 and the like can be prevented.

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

[0191] The sacrificial film 144 can be etched by wet etching or dry etching, but dry etching is preferable because it can prevent the pattern from shrinking.

[0192] [Etching of organic layer 116, organic layer 112, and organic layer 115] Subsequently, parts of organic layer 116, organic layer 112, and organic layer 115 that are not covered by sacrificial layer 145 are removed by etching to form slit 120. At the same time, the upper surface of connection electrode 111C is also exposed.

[0193] At this time, organic layer 112R, organic layer 112G, and a portion of organic layer 112B are separated by etching, forming layer 135R, which is a piece of organic layer 112R, layer 135G, which is a piece of organic layer 112G, and layer 135B, which is a piece of organic layer 112B.

[0194] In particular, dry etching using an etching gas that does not contain oxygen as a main component is preferably used for etching the organic layers 116, 112, and 115. This can suppress deterioration of the organic layers 116, 112, and 115, thereby achieving a highly reliable display device. Examples of etching gases that do not contain oxygen as a main component include CF4, C4F8, SF6, CHF3, Cl2, H2O, BCl3, H2, and noble gases (such as He). Also, a mixed gas of any of the above gases and a dilution gas that does not contain oxygen can be used as the etching gas.

[0195] The etching of the organic layers 116, 112, and 115 is not limited to the above, and may be dry etching using other gases or wet etching.

[0196] Furthermore, the etching rate can be increased by using an etching gas containing oxygen gas or dry etching using oxygen gas to etch the organic layer 116, the organic layer 112, and the organic layer 115. Therefore, etching can be performed under low power conditions while maintaining a sufficiently high etching rate, thereby reducing damage caused by etching. Furthermore, problems such as adhesion of reaction products generated during etching can be suppressed. For example, an etching gas obtained by adding oxygen gas to the above-mentioned etching gas that does not contain oxygen as a main component can be used.

[0197] When the organic layer 116, the organic layer 112, and the organic layer 115 are etched, the insulating layer 105 is exposed. Therefore, it is preferable to use a film that is highly resistant to etching of the organic layer 115 for the insulating layer 105. When the organic layer 115 is etched, the upper part of the insulating layer 105 may be etched, and the portion not covered by the organic layer 115 may become thinner.

[0198] The sacrificial layer 147 may be etched simultaneously when etching the organic layer 116, the organic layer 112, and the organic layer 115. Etching the organic layer 116, the organic layer 112, the organic layer 115, and the sacrificial layer 147 by the same treatment is preferable because it simplifies the process and reduces the manufacturing cost of the display device.

[0199] [Removal of Sacrificial Layer] Next, the sacrificial layer 147 is removed to expose the upper surface of the sacrificial layer 145 (FIG. 10C). At this time, it is preferable to leave the sacrificial layer 145. However, it is not necessary to remove the sacrificial layer 147 at this point.

[0200] [Formation of insulating film 125f] Subsequently, an insulating film 125f is formed to cover the sacrificial layer 145 and the slits 120.

[0201] The insulating film 125f functions as a barrier layer that prevents impurities such as water from diffusing into the EL layer. The insulating film 125f is preferably formed by the ALD method, which has excellent step coverage, because it can adequately cover the side surfaces of the EL layer.

[0202] The insulating film 125f is preferably made of the same material as the sacrificial layer 145, because they can be simultaneously etched in a later step. For example, the insulating film 125f and the sacrificial layer 145 are preferably made of an inorganic insulating material such as aluminum oxide, hafnium oxide, or silicon oxide formed by the ALD method.

[0203] The material that can be used for the insulating film 125f is not limited to this, and any material that can be used for the sacrificial film 144 can be used as appropriate.

[0204] [Formation of Resin Layer 126] Subsequently, a resin layer 126 is formed in the region overlapping with the slit 120 (FIG. 11A). The resin layer 126 can be formed by the same method as the resin layer 163.

[0205] Here, an example is shown in which the resin layer 126 is formed to have a width greater than the width of the slit 120.

[0206] [Etching of insulating film 125f and sacrificial layer 145] Subsequently, the insulating film 125f and the sacrificial layer 145 are etched away from the portions not covered by the resin layer 126 to expose the upper surface of the organic layer 116. At the same time, the insulating layer 125 and the sacrificial layer 145 are formed in the region covered by the resin layer 126 (FIG. 11B).

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

[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 ethyl alcohol, methyl alcohol, isopropyl alcohol (IPA), and glycerin can be used as the alcohol capable of dissolving the insulating film 125f and the sacrificial layer 145.

[0209] After removing the insulating film 125f and the sacrificial layer 145, it is preferable to perform a drying treatment to remove water contained inside the organic layer 115, the organic layer 112, and the organic layer 116 and water adsorbed on the surface. For example, it is preferable to perform a heat treatment in an inert gas atmosphere or a reduced pressure atmosphere. The heat treatment can be performed at a substrate temperature of 50°C or higher and 200°C or lower, preferably 60°C or higher and 150°C or lower, and more preferably 70°C or higher and 120°C or lower. A reduced pressure atmosphere is preferable because it allows drying at a lower temperature.

[0210] [Formation of organic layer 114] Subsequently, the organic layer 114 is formed to cover the organic layer 116, the insulating layer 125, the sacrificial layer 145, the resin layer 126, and the like.

[0211] The organic layer 114 can be formed by the same method as the organic layer 115. When the organic layer 114 is formed by vapor deposition, a shielding mask may be used to prevent the organic layer 114 from being formed on the connection electrode 111C.

[0212] [Formation of Common Electrode 113] Subsequently, the common electrode 113 is formed to cover the organic layer 114 .

[0213] The common electrode 113 can be formed by a film formation method such as evaporation or sputtering, or by stacking a film formed by evaporation and a film formed by sputtering.

[0214] The common electrode 113 is preferably formed so as to encompass the region where the organic layer 114 is formed. That is, the edge of the organic layer 114 can be configured to overlap the common electrode 113. The common electrode 113 may be formed using a shielding mask.

[0215] The connection section 130 has a configuration in which the organic layer 114 is sandwiched between the connection electrode 111C and the common electrode 113. In this case, it is preferable to use a material with as low an electrical resistance as possible for the organic layer 114. Alternatively, it is preferable to form the organic layer 114 as thin as possible to reduce the electrical 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 to 5 nm, preferably 1 nm to 3 nm, for the organic layer 114, it may be possible to reduce the electrical resistance between the connection electrode 111C and the common electrode 113 to a negligible level.

[0216] [Formation of protective layer] Next, a protective layer 121 is formed on the common electrode 113 (FIG. 11C). The inorganic insulating film used for the protective layer 121 is preferably formed by sputtering, PECVD, or ALD. The ALD method is particularly preferred because it has excellent step coverage and is less likely to cause defects such as pinholes. The inkjet method is also preferred for forming the organic insulating film because it can form a uniform film in the desired area.

[0217] In this manner, the display device shown in FIG. 7A can be manufactured.

[0218] In the above example, the resin layer 126 is formed to be wider than the slits 120, but the resin layer 126 and the slits 120 may be formed to have the same width.

[0219] FIG. 12A is a schematic cross-sectional view at the point in time when a resin layer 126 is formed after an insulating film 125f is formed.

[0220] 12A, after forming a resin layer 126 wider than the slit 120, the upper part of the resin layer 126 is etched by ashing or the like, so that the resin layer 126 is formed only inside the slit 120. In this case, it is preferable to bring the upper surface of the resin layer 126 as close as possible to the height of the upper surface of the adjacent organic layer 116. This can reduce the step caused by the slit 120 and improve the step coverage of the organic layer 114, etc.

[0221] Subsequently, the insulating film 125f and the sacrificial layer 145 are etched in the same manner as above (FIG. 12B). At this time, since no part of the sacrificial layer 145 is covered with the resin layer 126, the sacrificial layer 145 is removed without leaving any scraps.

[0222] Subsequently, the organic layer 114, the common electrode 113, and the protective layer 121 are formed in the same manner as above, thereby completing the production of a display device as shown in FIG. 12C.

[0223] 12C shows an example in which the organic layer 114 is not provided between the connection electrode 111C and the common electrode 113. Because the connection electrode 111C and the common electrode 113 are in contact with each other, the contact resistance between them can be made extremely small, and power consumption can be reduced.

[0224] This completes the description of the example of the method for manufacturing the display device.

[0225] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0226] (Embodiment 2) In this embodiment, a structural example of a display device according to one embodiment of the present invention will be described.

[0227] The display device of the present embodiment can be a high-resolution display device or a large-sized display device. Therefore, the display device of the present embodiment can be used in electronic devices having relatively large screens, such as television devices, desktop or notebook personal computers, computer monitors, digital signage, large game machines such as pachinko machines, as well as display units of digital cameras, digital video cameras, digital photo frames, mobile phones, portable game machines, smartphones, wristwatch-type terminals, tablet terminals, personal digital assistants, and sound reproducing devices.

[0228] [Display device 400] FIG. 13 shows a perspective view of display device 400, and FIG. 14A shows a cross-sectional view of display device 400.

[0229] The display device 400 has a configuration in which a substrate 452 and a substrate 451 are bonded together. In Fig. 13, the substrate 452 is clearly indicated by a dashed line.

[0230] The display device 400 includes a display unit 462, a circuit 464, wiring 465, etc. Fig. 13 shows an example in which an IC 473 and an FPC 472 are mounted on the display device 400. Therefore, the configuration shown in Fig. 13 can also be said to be a display module including the display device 400, an IC (integrated circuit), and an FPC.

[0231] The circuit 464 can be, for example, a scanning line driver circuit.

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

[0233] 13 shows an example in which an IC 473 is provided on a substrate 451 by a COG (Chip On Glass) method or a COF (Chip on Film) method. The IC 473 may be, for example, an IC having a scanning line driver circuit or a signal line driver circuit. Note that the display device 400 and the display module may not include an IC. Alternatively, the IC may be mounted on an FPC by a COF method or the like.

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

[0235] The display device 400 shown in FIG. 14A includes the transistor 202, the transistor 210, the light-emitting element 430b, the light-emitting element 430c, and the like between a substrate 453 and a substrate 454.

[0236] The light-emitting element described as an example in Embodiment 1 can be applied to the light-emitting element 430b and the light-emitting element 430c.

[0237] Here, when a pixel of a display device has three types of subpixels having light-emitting elements that emit different colors, the three subpixels include subpixels of three colors of red (R), green (G), and blue (B), or subpixels of three colors of yellow (Y), cyan (C), and magenta (M), etc. When a pixel of a display device has four subpixels, the four subpixels include subpixels of four colors of R, G, B, and white (W), or subpixels of four colors of R, G, B, and Y, etc.

[0238] The substrate 454 and the protective layer 416 are bonded together via an adhesive layer 442. The adhesive layer 442 is provided to overlap the light emitting element 430b and the light emitting element 430c, respectively, and a solid sealing structure is applied to the display device 400.

[0239] The light-emitting elements 430b and 430c each have a conductive layer 411a, a conductive layer 411b, and a conductive layer 411c as pixel electrodes. The conductive layer 411b is reflective to visible light and functions as a reflective electrode. The conductive layer 411c is transparent to visible light and functions as an optical adjustment layer.

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

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

[0242] Light emitted from the light-emitting element is emitted toward the substrate 452. The substrate 452 is preferably made of a material that is highly transparent to visible light.

[0243] The transistor 202 and the transistor 210 are both formed over a substrate 451. These transistors can be manufactured using the same material and the same process.

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

[0245] The display device 400 is manufactured by first bonding a fabrication substrate provided with the insulating layer 212, the transistors, the light-emitting elements, and the like to a substrate 454 provided with a light-shielding layer 417 with an adhesive layer 442. Then, the fabrication substrate is peeled off, and a substrate 453 is attached to the exposed surface, thereby transferring each component formed on the fabrication substrate to the substrate 453. The substrate 453 and the substrate 454 are preferably flexible. This can increase the flexibility of the display device 400.

[0246] The insulating layer 212 can be formed using the inorganic insulating film that can be used for the insulating layer 211 and the insulating layer 215, respectively.

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

[0248] The transistor 202 and the transistor 210 each include a conductive layer 221 functioning as a gate, an insulating layer 211 functioning as a gate insulating layer, a semiconductor layer 231 including a channel formation 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 functioning as a gate insulating layer, a conductive layer 223 functioning 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 formation region 231i. The insulating layer 225 is located between the conductive layer 223 and the channel formation region 231i.

[0249] The conductive layer 222a and the conductive layer 222b are each connected to the low-resistance region 231n through an opening provided in the insulating layer 215. One of the conductive layer 222a and the conductive layer 222b functions as a source, and the other functions as a drain.

[0250] 14A shows an example in which the top surface and side surfaces of the semiconductor layer are covered with an insulating layer 225. The conductive layer 222a and the conductive layer 222b are connected to the low-resistance region 231n through openings provided in the insulating layer 225 and the insulating layer 215, respectively.

[0251] On the other hand, in the transistor 209 shown in FIG. 14B, the insulating layer 225 overlaps with the channel formation region 231i of the semiconductor layer 231 but does not overlap with the low-resistance region 231n. For example, the structure shown in FIG. 14B can be manufactured by processing the insulating layer 225 using the conductive layer 223 as a mask. In FIG. 14B, the insulating layer 215 is provided to cover the insulating layer 225 and the conductive layer 223, and the conductive layer 222a and the conductive layer 222b are each connected to the low-resistance region 231n through openings in the insulating layer 215. Furthermore, an insulating layer 218 may be provided to cover the transistor.

[0252] The structure of the transistor included in the display device of this embodiment is not particularly limited. For example, a planar transistor, a staggered transistor, an inverted staggered transistor, or the like can be used. Furthermore, either a top-gate transistor or a bottom-gate transistor structure may be used. Alternatively, gates may be provided above and below a semiconductor layer in which a channel is formed.

[0253] The transistor 202 and the transistor 210 have a structure in which a semiconductor layer in which a channel is formed is sandwiched between two gates. The two gates may be connected and the same signal may be supplied to drive the transistor. Alternatively, the threshold voltage of the transistor may be controlled by applying a potential for controlling the threshold voltage to one of the two gates and a potential for driving to the other.

[0254] The crystallinity of a semiconductor material used for a semiconductor layer of a transistor is not particularly limited, and any of an amorphous semiconductor, a single-crystal semiconductor, and a semiconductor having crystallinity other than single crystal (a microcrystalline semiconductor, a polycrystalline semiconductor, or a semiconductor having a crystalline region in part) may be used. The use of a single-crystal semiconductor or a crystalline semiconductor is preferable because it can suppress deterioration of transistor characteristics.

[0255] The semiconductor layer of the transistor preferably includes a metal oxide (also referred to as an oxide semiconductor). That is, the display device of this embodiment preferably includes a transistor using a metal oxide for a channel formation region (hereinafter referred to as an OS transistor).

[0256] The band gap of the metal oxide used for the semiconductor layer of the transistor is preferably 2 eV or more, more preferably 2.5 eV or more. Use of a metal oxide with a wide band gap can reduce the off-state current of the OS transistor.

[0257] The metal oxide preferably contains at least indium or zinc, and more preferably contains indium and zinc. For example, the metal oxide preferably contains indium, M (where M is one or more selected from 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 one or more selected from gallium, aluminum, yttrium, and tin, and more preferably gallium. Note that a metal oxide containing indium, M, and zinc may be referred to as an In-M-Zn oxide hereinafter.

[0258] When the metal oxide is an In-M-Zn oxide, the atomic ratio of In in the In-M-Zn oxide is preferably equal to or greater than the atomic ratio of M. Examples of atomic ratios of metal elements in such In-M-Zn oxides include compositions in which In:M:Zn=1:1:1 or thereabouts, In:M:Zn=1:1:1.2 or thereabouts, In:M:Zn=2:1:3 or thereabouts, In:M:Zn=3:1:2 or thereabouts, In:M:Zn=4:2:3 or thereabouts, In:M:Zn=4:2:4.1 or thereabouts, In:M:Zn=5:1:3 or thereabouts, In:M:Zn=5:1:6 or thereabouts, In:M:Zn=5:1:7 or thereabouts, In:M:Zn=5:1:8 or thereabouts, In:M:Zn=6:1:6 or thereabouts, and In:M:Zn=5:2:5 or thereabouts, etc. Note that "nearby compositions" includes a range of ±30% of the desired atomic ratio. By increasing the atomic ratio of indium in the metal oxide, the on-state current, field-effect mobility, and the like of a transistor can be increased.

[0259] For example, when describing a composition with an atomic ratio of In:Ga:Zn=4:2:3 or thereabout, this includes a case where, when the atomic ratio of In is 4, the atomic ratio of Ga is 1 to 3 and the atomic ratio of Zn is 2 to 4. Furthermore, when describing a composition with an atomic ratio of In:Ga:Zn=5:1:6 or thereabout, this includes a case where, when the atomic ratio of In is 5, the atomic ratio of Ga is greater than 0.1 and less than 2 and the atomic ratio of Zn is greater than 5 and less than 7. Furthermore, when describing a composition with an atomic ratio of In:Ga:Zn=1:1:1 or thereabout, this includes a case where, when the atomic ratio of In is 1, the atomic ratio of Ga is greater than 0.1 and less than 2 and the atomic ratio of Zn is greater than 0.1 and less than 2.

[0260] The atomic ratio of In in the In-M-Zn oxide may be less than the atomic ratio of M. Examples of atomic ratios of metal elements in such In-M-Zn oxide include compositions of In:M:Zn=1:3:2 or thereabouts, In:M:Zn=1:3:3 or thereabouts, and In:M:Zn=1:3:4 or thereabouts. Increasing the atomic ratio of M in the metal oxide increases the band gap of the In-M-Zn oxide, thereby improving its resistance to negative bias stress testing under light irradiation. Specifically, it reduces the change in threshold voltage or shift voltage (Vsh) measured in a negative bias temperature illumination stress (NBTIS) test of a transistor. The shift voltage (Vsh) is defined as the Vg at which the tangent to the maximum slope of the drain current (Id)-gate voltage (Vg) curve of the transistor intersects with the line at Id=1 pA.

[0261] Alternatively, the semiconductor layer of the transistor may contain silicon, such as amorphous silicon or crystalline silicon (such as low-temperature polysilicon or single-crystal silicon).

[0262] Alternatively, the semiconductor layer of the transistor may include a layered material that functions as a semiconductor. A layered material is a general term for a group of materials that have a layered crystal structure. A layered crystal structure is a structure in which layers formed by covalent or ionic bonds are stacked via bonds weaker than covalent or ionic bonds, such as van der Waals forces. A layered material has high electrical conductivity within a unit layer, that is, high two-dimensional electrical conductivity. By using a material that functions as a semiconductor and has high two-dimensional electrical conductivity in the channel formation region, a transistor with a large on-state current can be provided.

[0263] Examples of the layered material include graphene, silicene, and chalcogenides. Chalcogenides are compounds containing chalcogen (elements belonging to Group 16). Examples of chalcogenides include transition metal chalcogenides and Group 13 chalcogenides. Specific examples of transition metal chalcogenides applicable to the semiconductor layer of a transistor include molybdenum sulfide (typically MoS2), molybdenum selenide (typically MoSe2), molybdenum tellurium (typically MoTe2), tungsten sulfide (typically WS2), tungsten selenide (typically WSe2), tungsten tellurium (typically WTe2), hafnium sulfide (typically HfS2), hafnium selenide (typically HfSe2), zirconium sulfide (typically ZrS2), and zirconium selenide (typically ZrSe2).

[0264] The transistors included in the circuit 464 may have the same structure as or different from the transistors included in the display portion 462. The transistors included in the circuit 464 may all have the same structure or may have two or more types of structures. Similarly, the transistors included in the display portion 462 may all have the same structure or may have two or more types of structures.

[0265] At least one insulating layer covering the transistor is preferably made of a material that is resistant to the diffusion of impurities such as water and hydrogen. This allows the insulating layer to function as a barrier layer. With this structure, it is possible to effectively prevent impurities from diffusing into the transistor from the outside, thereby improving the reliability of the display device.

[0266] It is preferable to use an inorganic insulating film for each of the insulating layers 211, 212, 215, 218, and 225. Examples of the inorganic insulating film that can be used include a silicon nitride film, a silicon oxynitride film, a silicon oxide film, a silicon nitride oxide film, an aluminum oxide film, and an aluminum nitride film. Alternatively, a hafnium oxide film, an yttrium oxide film, a zirconium oxide film, a gallium oxide film, a tantalum oxide film, a magnesium oxide film, a lanthanum oxide film, a cerium oxide film, and a neodymium oxide film may also be used. Two or more of the above-described inorganic insulating films may be stacked.

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

[0268] An organic insulating film is suitable for the insulating layer 214, which functions as a planarizing layer. Materials that can be used for the organic insulating film include acrylic resin, polyimide resin, epoxy resin, polyamide resin, polyimideamide resin, siloxane resin, benzocyclobutene resin, phenol resin, and precursors of these resins.

[0269] It is preferable to provide a light-shielding layer 417 on the surface of substrate 454 facing substrate 453. In addition, various optical members can be arranged on the outside of substrate 454. Examples of optical members include a polarizing plate, a retardation plate, a light diffusion layer (such as a diffusion film), an anti-reflection layer, and a light-collecting film. In addition, an antistatic film that suppresses the adhesion of dust, a water-repellent film that makes it difficult for dirt to adhere, a hard coat film that suppresses the occurrence of scratches during use, an impact absorbing layer, etc. may be arranged on the outside of substrate 454.

[0270] By providing the protective layer 416 that covers the light-emitting element, impurities such as water can be prevented from entering the light-emitting element, and the reliability of the light-emitting element can be improved.

[0271] 14A shows a connection portion 228. The common electrode 413 and a wiring are electrically connected at the connection portion 228. FIG. 14A shows an example in which the same layered structure as that of the pixel electrode is applied to the wiring.

[0272] The substrate 453 and the substrate 454 can each be made of glass, quartz, ceramic, sapphire, resin, metal, alloy, semiconductor, or the like. A material that transmits light is used for the substrate on the side from which light from the light-emitting element is extracted. Using a flexible material for the substrate 453 and the substrate 454 can increase the flexibility of the display device. Alternatively, a polarizing plate may be used for the substrate 453 or the substrate 454.

[0273] Substrates 453 and 454 can be made of polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyacrylonitrile resin, acrylic resin, polyimide resin, polymethyl methacrylate resin, polycarbonate (PC) resin, polyethersulfone (PES) resin, polyamide resin (nylon, aramid, etc.), polysiloxane resin, cycloolefin resin, polystyrene resin, polyamideimide resin, polyurethane resin, polyvinyl chloride resin, polyvinylidene chloride resin, polypropylene resin, polytetrafluoroethylene (PTFE) resin, ABS resin, cellulose nanofiber, etc. One or both of substrates 453 and 454 may be made of glass having a thickness sufficient to provide flexibility.

[0274] When a circularly polarizing plate is superimposed on a display device, it is preferable that the display device has a substrate with high optical isotropy. A substrate with high optical isotropy has small birefringence (or a small amount of birefringence).

[0275] The absolute value of the retardation (phase difference) of a substrate having high optical isotropy is preferably 30 nm or less, more preferably 20 nm or less, and even more preferably 10 nm or less.

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

[0277] Furthermore, when a film is used as a substrate, the film may absorb water, causing deformation such as wrinkles in the display panel. Therefore, it is preferable to use a film with low water absorption for the substrate. For example, it is preferable to use a film with a water absorption rate of 1% or less, more preferably 0.1% or less, and even more preferably 0.01% or less.

[0278] The adhesive layer can be made of various curable adhesives, such as photo-curable adhesives (e.g., ultraviolet curable), reactive curable adhesives, thermosetting adhesives, and anaerobic adhesives. Examples of such adhesives include epoxy resin, acrylic resin, silicone resin, phenolic resin, polyimide resin, imide resin, PVC (polyvinyl chloride) resin, PVB (polyvinyl butyral) resin, and EVA (ethylene vinyl acetate) resin. Materials with low moisture permeability, such as epoxy resin, are particularly preferred. Two-component resins may also be used. Adhesive sheets, etc., may also be used.

[0279] The connection layer 242 may be made of an anisotropic conductive film (ACF), an anisotropic conductive paste (ACP), or the like.

[0280] Materials that can be used for conductive layers such as the gate, source, and drain of a transistor, as well as various wirings and electrodes that constitute a display device include metals such as aluminum, titanium, chromium, nickel, copper, yttrium, zirconium, molybdenum, silver, tantalum, and tungsten, and alloys containing these metals as main components, etc. Films containing these materials can be used as a single layer or a stacked layer structure.

[0281] Examples of light-transmitting conductive materials include conductive oxides such as indium oxide, indium tin oxide, indium zinc oxide, zinc oxide, and zinc oxide containing gallium, or graphene. Alternatively, metal materials such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, and titanium, or alloy materials containing such metal materials, can be used. Alternatively, nitrides of such metal materials (e.g., titanium nitride) can be used. When using metal materials or alloy materials (or their nitrides), it is preferable to thin them sufficiently to ensure light-transmitting properties. A stacked film of the above materials can also be used as the conductive layer. For example, a stacked film of an alloy of silver and magnesium and indium tin oxide is preferable because it can enhance conductivity. These can also be used for conductive layers such as various wirings and electrodes constituting a display device, and for conductive layers (conductive layers functioning as pixel electrodes or common electrodes) of light-emitting elements.

[0282] Examples of insulating materials that can be used for each insulating layer include resins such as acrylic resin and epoxy resin, and inorganic insulating materials such as silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, and aluminum oxide.

[0283] At least a part of the configuration examples exemplified in this embodiment and the corresponding drawings can be combined as appropriate with other configuration examples or drawings.

[0284] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0285] (Embodiment 3) An example of the configuration of a pixel in a display unit of a display device will be described below.

[0286] The display device 100 shown in Fig. 1A is an example in which a stripe arrangement is applied. In Fig. 1A, the display device is composed of three subpixels, R, G, and B. The subpixels R, G, and B each have a light-emitting device that emits a different color. For example, the subpixels R, G, and B can be red, green, and blue subpixels, respectively.

[0287] An S-stripe arrangement is applied to the pixel 103 shown in Fig. 15A. The pixel 103 shown in Fig. 15A is composed of three sub-pixels, R, G, and B sub-pixels.

[0288] The pixel 103 shown in FIG. 15B has subpixel G having a generally trapezoidal top surface shape with rounded corners, subpixel R having a generally triangular top surface shape with rounded corners, and subpixel B having a generally rectangular or hexagonal top surface shape with rounded corners. Subpixel G has a larger light-emitting area than subpixel R. In this manner, the shape and size of each subpixel can be determined independently. For example, the more reliable the light-emitting device, the smaller the size can be. For example, subpixel R may be a red subpixel, subpixel G a green subpixel, and subpixel B a blue subpixel.

[0289] The pixels 125a and 125b shown in Fig. 15C are arranged in a Pentile array. Fig. 15C shows an example in which pixel 125a having subpixels R and G and pixel 125b having subpixels G and B are arranged alternately. For example, subpixel R may be a red subpixel, subpixel G may be a green subpixel, and subpixel B may be a blue subpixel.

[0290] Pixels 125a and 125b shown in Figures 15D and 15E are arranged in a delta configuration. Pixel 125a has two subpixels (subpixels R and G) in the top row (first row) and one subpixel (subpixel B) in the bottom row (second row). Pixel 125b has one subpixel (subpixel B) in the top row (first row) and two subpixels (subpixels R and G) in the bottom row (second row).

[0291] FIG. 15D shows an example in which each subpixel has a substantially rectangular top surface shape with rounded corners, and FIG. 15E shows an example in which each subpixel has a circular top surface shape.

[0292] In photolithography, the finer the pattern to be processed, the more significant the effect of light diffraction becomes. This reduces the fidelity of the photomask pattern when it is transferred by exposure, making it difficult to process the resist mask into the desired shape. Therefore, even if the photomask pattern is rectangular, it is likely to have rounded corners. As a result, the top surface shape of the subpixel may become a polygon with rounded corners, an ellipse, a circle, or the like.

[0293] Furthermore, in a manufacturing method of a display device according to one embodiment of the present invention, the EL layer is processed into an island shape using a resist mask. The resist 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 material for the EL layer and the curing temperature of the resist material, the resist film may not be cured sufficiently. A resist film that is not cured sufficiently may have a shape that is different from the desired shape during processing. As a result, the top surface shape of the EL layer may become a polygon with rounded corners, an ellipse, a circle, or the like. For example, when a resist mask with a square top surface shape is formed, a resist mask with a circular top surface shape may be formed, resulting in a circular top surface shape of the EL layer.

[0294] In order to obtain a desired top surface shape for the EL layer, a technique for correcting the mask pattern in advance (OPC (Optical Proximity Correction) technique) may be used so that the design pattern and the transfer pattern match. Specifically, OPC technique adds correction patterns to the corners of the figures on the mask pattern.

[0295] The pixel 103 shown in Figures 16A to 16C has a stripe arrangement. The pixel 103 shown in Figures 16A to 16C is composed of four subpixels: R, G, B, and W. The subpixels R, G, B, and W each have a light-emitting device that emits a different color. For example, the subpixels R, G, B, and W can be red, green, blue, and white, respectively.

[0296] FIG. 16A shows an example in which each subpixel has a rectangular top surface shape, FIG. 16B shows an example in which each subpixel has a top surface shape that combines two semicircles and a rectangle, and FIG. 16C shows an example in which each subpixel has an elliptical top surface shape.

[0297] 16D to 16F is configured with four sub-pixels, R, G, B, and W, and has a matrix arrangement.

[0298] Fig. 16D shows an example in which each subpixel has a square top surface, Fig. 16E shows an example in which each subpixel has a substantially square top surface with rounded corners, Fig. 16F shows an example in which each subpixel has a circular top surface, and Fig. 16G shows an example in which striped arrangement subpixels R, G, and B and three subpixels W are used.

[0299] (Fourth embodiment) In this embodiment, a light-emitting element (also referred to as a light-emitting device) that can be used for a display device that is one embodiment of the present invention will be described.

[0300] In this specification, etc., a device fabricated using a metal mask or FMM (fine metal mask, high-resolution metal mask) may be referred to as a device with an MM (metal mask) structure. Also, in this specification, etc., a device fabricated without using a metal mask or FMM may be referred to as a device with an MML (metal maskless) structure.

[0301] In this specification, a structure in which different light-emitting layers are formed or different light-emitting layers are painted for each color light-emitting device (here, blue (B), green (G), and red (R)) may be referred to as an SBS (Side By Side) structure. In this specification, a light-emitting device that can emit white light may be referred to as a white light-emitting device. In addition, a white light-emitting device can be combined with a colored layer (for example, a color filter) to form a full-color display device.

[0302] Furthermore, light-emitting devices can be broadly divided into single structures and tandem structures. A single-structure device has one light-emitting unit between a pair of electrodes, and the light-emitting unit preferably includes one or more light-emitting layers. To obtain white light emission with a single structure, two or more light-emitting layers may be selected so that the light emitted from each of the two or more light-emitting layers has a complementary color relationship. For example, by making the emission color of the first light-emitting layer and the emission color of the second light-emitting layer complementary, a configuration in which the entire light-emitting device emits white light can be obtained. The same applies to light-emitting devices having three or more light-emitting layers.

[0303] A tandem-structure device preferably has two or more light-emitting units between a pair of electrodes, and each light-emitting unit preferably includes one or more light-emitting layers. By using light-emitting layers that emit light of the same color in each light-emitting unit, the brightness per given current can be increased, and the device can be made more reliable than a single-structure light-emitting device. To obtain white light emission in a tandem structure, the light from the light-emitting layers of the multiple light-emitting units can be combined to obtain white light emission. The combination of light-emitting colors that can produce white light emission is the same as in the single-structure configuration. In a tandem-structure 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 above-mentioned white light-emitting device (single structure or tandem structure) with a light-emitting device having an SBS structure, the light-emitting device having an SBS structure can reduce power consumption compared to the white light-emitting device. When it is desired to keep power consumption low, it is preferable to use a light-emitting device having an SBS structure. On the other hand, the manufacturing process of a white light-emitting device is simpler than that of a light-emitting device having an SBS structure, and therefore the manufacturing cost can be reduced or the manufacturing yield can be increased, making it preferable.

[0305] <Example of light-emitting device configuration> As shown in FIG. 17A, the light-emitting device has an EL layer 786 between a pair of electrodes (a lower electrode 772 and an upper electrode 788). The EL layer 786 can be composed of multiple layers, such as a layer 4420, a light-emitting layer 4411, and a layer 4430. The layer 4420 can have, for example, a layer containing a substance with high electron injection properties (electron injection layer) and a layer containing a substance with high electron transport properties (electron transport layer). The light-emitting layer 4411 contains, for example, a light-emitting compound. The layer 4430 can have, for example, a layer containing a substance with high hole injection properties (hole injection layer) and a layer containing a substance with high hole transport properties (hole transport layer).

[0306] A structure having the layer 4420, the light-emitting layer 4411, and the layer 4430 provided between a pair of electrodes can function as a single light-emitting unit, and the structure of FIG. 17A is referred to as a single structure in this specification.

[0307] 17B shows a modified example of the EL layer 786 of the light-emitting device shown in Fig. 17A. Specifically, the light-emitting device shown in Fig. 17B has a layer 4430-1 on the lower electrode 772, a layer 4430-2 on the layer 4430-1, a light-emitting layer 4411 on the layer 4430-2, a layer 4420-1 on the light-emitting layer 4411, a layer 4420-2 on the layer 4420-1, and an upper electrode 788 on the layer 4420-2. For example, when the lower electrode 772 is an anode and the upper electrode 788 is a cathode, the layer 4430-1 functions as a hole injection layer, the layer 4430-2 functions as a hole transport layer, the layer 4420-1 functions as an electron transport layer, and the layer 4420-2 functions as an electron injection layer. Alternatively, when the lower electrode 772 is used as a cathode and the upper electrode 788 is used as an anode, the layer 4430-1 functions as an electron injection layer, the layer 4430-2 functions as an electron transport layer, the layer 4420-1 functions as a hole transport layer, and the layer 4420-2 functions as a hole injection layer. By using such a layer structure, it is possible to efficiently inject carriers into the light-emitting layer 4411 and increase the efficiency of carrier recombination in the light-emitting layer 4411.

[0308] As shown in FIGS. 17C and 17D, a configuration in which a plurality of light-emitting layers (light-emitting layers 4411, 4412, 4413) are provided between layer 4420 and layer 4430 is also a variation of the single structure.

[0309] 17E and 17F, a configuration in which a plurality of light-emitting units (EL layer 786a, EL layer 786b) are connected in series via an intermediate layer (charge generating layer) 4440 is referred to as a tandem structure in this specification. Note that, although the configuration shown in FIGS. 17E and 17F is referred to as a tandem structure in this specification and the like, it is not limited thereto, and for example, the tandem structure may also be referred to as a stack structure. Note that by using a tandem structure, a light-emitting device capable of emitting light with high brightness can be obtained.

[0310] In FIG. 17C, light-emitting layers 4411, 4412, and 4413 may be made of light-emitting materials that emit light of the same color.

[0311] Different light-emitting materials may be used for the light-emitting layer 4411, the light-emitting layer 4412, and the light-emitting layer 4413. When the light emitted from the light-emitting layer 4411, the light-emitting layer 4412, and the light-emitting layer 4413 has a complementary color relationship, white light can be obtained. Figure 17D shows an example in which a colored layer 785 that functions as a color filter is provided. When white light passes through the color filter, light of a desired color can be obtained.

[0312] 17E, the same light-emitting material may be used for the light-emitting layer 4411 and the light-emitting layer 4412. Alternatively, light-emitting materials that emit light of different colors may be used for the light-emitting layer 4411 and the light-emitting layer 4412. When the light emitted by the light-emitting layer 4411 and the light emitted by the light-emitting layer 4412 are complementary colors, white light is obtained. FIG. 17F shows an example in which a colored layer 785 is further provided.

[0313] 17C, 17D, 17E, and 17F, the layer 4420 and the layer 4430 may have a laminated structure made up of two or more layers, as shown in FIG. 17B.

[0314] A structure in which different light-emitting layers (here, blue (B), green (G), and red (R)) are created for each light-emitting device is sometimes called an SBS (Side By Side) structure.

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

[0316] A light-emitting device that emits white light preferably has a configuration in which the light-emitting layer contains two or more types of light-emitting materials. To obtain white light emission, it is sufficient to select light-emitting materials such that the light emitted by each of the two or more light-emitting materials has a complementary color relationship. For example, by making the color of the light emitted by the first light-emitting layer and the color of the light emitted by the second light-emitting layer complementary, a light-emitting device that emits white light as a whole can be obtained. The same applies to light-emitting devices having three or more light-emitting layers.

[0317] The light-emitting layer preferably contains two or more light-emitting materials that emit light of R (red), G (green), B (blue), Y (yellow), O (orange), etc. Alternatively, it is preferable that the light-emitting layer contains two or more light-emitting materials, and the light emitted by each of the light-emitting materials contains spectral components of two or more colors of R, G, and B.

[0318] Here, a specific example of the configuration of the light-emitting device will be described.

[0319] The light-emitting device has at least a light-emitting layer. The light-emitting device may further have, in addition to the light-emitting layer, a layer containing a substance with high hole-injection properties, a substance with high hole-transport properties, a hole-blocking material, a substance with high electron-transport properties, an electron-blocking material, a substance with high electron-injection properties, or a bipolar substance (a substance with high electron-transport properties and high hole-transport properties).

[0320] The light-emitting device can be made of either a low-molecular-weight compound or a high-molecular-weight compound, and may contain an inorganic compound. The layers constituting the light-emitting device can be formed by a method such as vapor deposition (including vacuum vapor deposition), transfer, printing, inkjet printing, or coating.

[0321] For example, the light-emitting device may have a configuration including, in addition to a light-emitting layer, one or more layers selected from the group consisting of a hole-injection layer, a hole-transport layer, a hole-blocking layer, an electron-blocking 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, such as an aromatic amine compound and a composite material containing a hole transport material and an acceptor material (electron acceptor material).

[0323] The hole transport layer is a layer that transports holes injected from the anode by the hole injection layer to the light emitting layer. The hole transport layer is a layer that contains a hole transport material. The hole transport material is a material having a concentration of 1×10 -6 cm 2A material having a hole mobility of 1 / Vs or more is preferred. Note that other materials can also be used as long as they have a higher hole transporting property than electron transporting property. As the hole transporting material, a material having a high hole transporting property, such as a π-electron-rich heteroaromatic compound (e.g., a carbazole derivative, a thiophene derivative, a furan derivative, etc.) or an aromatic amine (a compound having an aromatic amine skeleton), is preferred.

[0324] The electron transport layer is a layer that transports electrons injected from the cathode by the electron injection layer to the light emitting layer. The electron transport layer is a layer that contains an electron transporting material. The electron transporting material is a material having a molecular weight of 1×10 -6 cm 2 A substance having an electron mobility of 1 / Vs or more is preferred. Note that other substances can also be used as long as they have a higher electron transporting property than holes. Examples of electron-transporting materials that can be used include metal complexes having a quinoline skeleton, metal complexes having a benzoquinoline skeleton, metal complexes having an oxazole skeleton, and metal complexes having a thiazole skeleton, as well as oxadiazole derivatives, triazole derivatives, imidazole derivatives, oxazole derivatives, thiazole derivatives, phenanthroline derivatives, quinoline derivatives having a quinoline ligand, benzoquinoline derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, and π-electron-deficient heteroaromatic compounds including nitrogen-containing heteroaromatic compounds.

[0325] The electron injection layer is a layer that injects electrons from the cathode to the electron transport layer and contains a material with high electron injection properties. Examples of the material with high electron injection properties include alkali metals, alkaline earth metals, and compounds thereof. Examples of the material with high electron injection properties include a composite material containing an electron transport material and a donor material (electron donor material).

[0326] Examples of the electron injection layer include lithium, cesium, lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF), 8-(quinolinolato)lithium (abbreviation: Liq), 2-(2-pyridyl)phenolatolithium (abbreviation: LiPP), 2-(2-pyridyl)-3-pyridinolatolithium (abbreviation: LiPPy), 4-phenyl-2-(2-pyridyl)phenolatolithium (abbreviation: LiPPP), and lithium oxide (LiO x ), alkali metals such as cesium carbonate, alkaline earth metals, or compounds thereof can be used.

[0327] Alternatively, the electron injection layer may be formed using a material having electron transport properties. For example, a compound having an unshared electron pair and an electron-deficient heteroaromatic ring may be used as the material having electron transport properties. Specifically, a compound having at least one of a pyridine ring, a diazine ring (pyrimidine ring, pyrazine ring, pyridazine ring), and a triazine ring may be used.

[0328] The lowest unoccupied molecular orbital (LUMO) of an organic compound having an unshared electron pair is preferably -3.6 eV or more and -2.3 eV or less. Generally, the highest occupied molecular orbital (HOMO) level and the LUMO level of an organic compound can be estimated by CV (cyclic voltammetry), photoelectron spectroscopy, optical absorption spectroscopy, inverse photoelectron spectroscopy, etc.

[0329] Examples of organic compounds with lone electron pairs include 4,7-diphenyl-1,10-phenanthroline (abbreviated as BPhen), 2,9-bis(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviated as NBPhen), diquinoxalino[2,3-a:2',3'-c]phenazine (abbreviated as HATNA), and 2,4,6-tris[3'-(pyridin-3-yl)biphenyl-3-yl]-1,3,5-triazine (abbreviated as TmPPPyTz). NBPhen has a higher glass transition temperature (Tg) and better heat resistance than BPhen.

[0330] The light-emitting layer is a layer containing a light-emitting substance. The light-emitting layer can contain one or more light-emitting substances. As the light-emitting substance, a substance that emits light of a color such as blue, purple, blue-purple, green, yellow-green, yellow, orange, or red is appropriately used. Furthermore, a substance that emits near-infrared light can also be used as the light-emitting substance.

[0331] Examples of light-emitting materials include fluorescent materials, phosphorescent materials, TADF materials, and quantum dot materials.

[0332] Examples of fluorescent materials include pyrene derivatives, anthracene derivatives, triphenylene derivatives, fluorene derivatives, carbazole derivatives, dibenzothiophene derivatives, dibenzofuran derivatives, dibenzoquinoxaline derivatives, quinoxaline derivatives, pyridine derivatives, pyrimidine derivatives, phenanthrene derivatives, and naphthalene derivatives.

[0333] Examples of phosphorescent materials include organometallic complexes (particularly iridium complexes) having a 4H-triazole skeleton, a 1H-triazole skeleton, an imidazole skeleton, a pyrimidine skeleton, a pyrazine skeleton, or a pyridine skeleton; organometallic complexes (particularly iridium complexes) having a phenylpyridine derivative having an electron-withdrawing group as a ligand; platinum complexes; and rare earth metal complexes.

[0334] The light-emitting layer may contain one or more organic compounds (host materials, assist materials, etc.) in addition to a light-emitting substance (guest material). One or more organic compounds may be a hole-transporting material or an electron-transporting material, or both. Alternatively, a bipolar material or a TADF material may be used as the one or more organic compounds.

[0335] The light-emitting layer preferably contains, for example, a phosphorescent material and a hole-transporting material and an electron-transporting material that are a combination that easily forms an exciplex. This configuration allows for efficient emission using Exciplex-Triplet Energy Transfer (ExTET), which is energy transfer from the exciplex to the light-emitting material (phosphorescent material). By selecting a combination that forms an exciplex that emits light that overlaps with the wavelength of the lowest-energy absorption band of the light-emitting material, the energy transfer becomes smooth, allowing for efficient emission. This configuration simultaneously enables high efficiency, low-voltage operation, and long life of the light-emitting device.

[0336] At least a part of the configuration examples exemplified in this embodiment and the corresponding drawings can be combined as appropriate with other configuration examples or drawings.

[0337] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0338] (Embodiment 5) In this embodiment, an example in which a display device of one embodiment of the present invention includes a light-receiving device or the like will be described.

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

[0340] There are no particular limitations on the arrangement of the sub-pixels, and various methods can be applied, including, for example, a stripe arrangement, an S-stripe arrangement, a matrix arrangement, a delta arrangement, a Bayer arrangement, and a pentile arrangement.

[0341] Examples of the top surface shape of the sub-pixel include a triangle, a quadrangle (including a rectangle and a square), a polygon such as a pentagon, a polygon with rounded corners, an ellipse, a circle, etc. Here, the top surface shape of the sub-pixel corresponds to the top surface shape of the light-emitting region of the light-emitting device.

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

[0343] In a display device having a light-emitting device and a light-receiving device in each pixel, the pixel has a light-receiving function, so that it is possible to detect contact or proximity of an object while displaying an image. For example, in addition to displaying an image using all of the sub-pixels of the display device, some of the sub-pixels can emit light as a light source and the remaining sub-pixels can display an image.

[0344] A display device according to one embodiment of the present invention has a display portion in which light-emitting devices are arranged in a matrix, and can display an image on the display portion. Furthermore, light-receiving devices are arranged in a matrix on the display portion, and the display portion has an imaging function and / or a sensing function in addition to an image display function. The display portion can be used as an image sensor or a touch sensor. That is, by detecting light in the display portion, an image can be captured or the proximity or contact of an object (such as a finger, a hand, or a pen) can be detected. Furthermore, the display device according to one embodiment of the present invention can use a light-emitting device as a light source for a sensor. Therefore, a light-receiving portion and a light source are not required separately from the display device, and the number of components in an electronic device can be reduced.

[0345] In a display device of one embodiment of the present invention, when light emitted from a light-emitting device included in a display portion is reflected (or scattered) by an object, the light-receiving device can detect the reflected light (or scattered light). Therefore, imaging or touch detection is possible even in a dark place.

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

[0347] For example, an image sensor can be used to acquire data related to biometric information such as fingerprints and palm prints. That is, a biometric authentication sensor can be built into the display device. By building a biometric authentication sensor into the display device, the number of components in the electronic device can be reduced compared to when a biometric authentication sensor is provided separately from the display device, and the electronic device can be made smaller and lighter.

[0348] Furthermore, when the light-receiving device is used as a touch sensor, the display device can detect the proximity or contact of an object using the light-receiving device.

[0349] The light receiving device can be, for example, a pn-type or pin-type photodiode. The light receiving device functions as a photoelectric conversion device (also called a photoelectric conversion element) that detects light incident on the light receiving device and generates electric charges. The amount of electric charges generated by the light receiving device is determined based on the amount of light incident on the light receiving device.

[0350] In particular, it is preferable to use an organic photodiode having a layer containing an organic compound as the light-receiving device. Organic photodiodes can be easily made thin, lightweight, and large in area, and have a high degree of freedom in shape and design, making them applicable to a variety of display devices.

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

[0352] The pixel shown in FIGS. 18A and 18B has subpixels G, B, R, and PS.

[0353] A stripe arrangement is applied to the pixels shown in Fig. 18A, and a matrix arrangement is applied to the pixels shown in Fig. 18B.

[0354] The pixel shown in FIGS. 18C and 18D has a subpixel G, a subpixel B, a subpixel R, a subpixel PS, and a subpixel IRS.

[0355] 18C and 18D show examples in which one pixel is arranged across two rows and three columns. Three subpixels (subpixel G, subpixel B, and subpixel R) are provided in the top row (first row). In FIG. 18C, three subpixels (one subpixel PS and two subpixels IRS) are provided in the bottom row (second row). On the other hand, in FIG. 18D, two subpixels (one subpixel PS and one subpixel IRS) are provided in the bottom row (second row). Note that the layout of the subpixels is not limited to the configurations in FIGS. 18A to 18D.

[0356] Subpixel R has a light-emitting device that emits red light, subpixel G has a light-emitting device that emits green light, and subpixel B has a light-emitting device that emits blue light.

[0357] The subpixels PS and IRS each have a light receiving device, and there is no particular limitation on the wavelength of light that the subpixels PS and IRS detect.

[0358] The light-receiving area of ​​the sub-pixel PS is smaller than that of the sub-pixel IRS. The smaller the light-receiving area, the narrower the imaging range, making it possible to suppress blurring in the imaging results and improve resolution. Therefore, using the sub-pixel PS makes it possible to capture images with higher definition or resolution than when using the sub-pixel IRS. For example, the sub-pixel PS can be used to capture images for personal authentication using fingerprints, palm prints, irises, pulse patterns (including vein patterns and artery patterns), faces, etc.

[0359] The light receiving device included in the subpixel PS preferably detects visible light, and preferably detects one or more of the colors blue, purple, blue-purple, green, yellow-green, yellow, orange, red, etc. The light receiving device included in the subpixel PS may also detect infrared light.

[0360] The sub-pixel IRS can be used as a touch sensor (also called a direct touch sensor) or a near-touch sensor (also called a hover sensor, hover touch sensor, non-contact sensor, or touchless sensor). The wavelength of light to be detected by the sub-pixel IRS can be determined appropriately depending on the application. For example, it is preferable that the sub-pixel IRS detects infrared light. This enables touch detection even in dark places.

[0361] Here, a touch sensor or near-touch sensor can detect the proximity or contact of an object (such as a finger, hand, or pen). A touch sensor can detect an object when the display device and the object are in direct contact with each other. A near-touch sensor can detect an object even if the object does not touch the display device. For example, a configuration in which the display device can detect an object when the distance between the display device and the object is in the range of 0.1 mm to 300 mm, preferably 3 mm to 50 mm, is preferable. This configuration makes it possible to operate the display device without the object directly touching it, in other words, to operate the display device in a contactless (touchless) manner. This configuration reduces the risk of the display device becoming dirty or scratched, or makes it possible to operate the display device without the object directly touching dirt (e.g., dust, viruses, etc.) attached to the display device.

[0362] By incorporating two types of light-receiving devices into one pixel, two additional functions can be added in addition to the display function, making it possible to multi-function the display device.

[0363] In order to capture high-resolution images, it is preferable that sub-pixels PS be provided in all pixels of the display device. On the other hand, sub-pixels IRS used in touch sensors or near-touch sensors do not require as high detection accuracy as sub-pixels PS, so they may be provided in only some of the pixels of the display device. By making the number of sub-pixels IRS in the display device smaller than the number of sub-pixels PS, the detection speed can be increased.

[0364] Here, the configuration of a light receiving device that can be used for the subpixels PS and IRS will be described.

[0365] The light-receiving device has at least an active layer that functions as a photoelectric conversion layer between a pair of electrodes. In this specification and the like, one of the pair of electrodes may be referred to as a pixel electrode and the other as a common electrode.

[0366] Of the pair of electrodes in a light-receiving device, one electrode functions as an anode and the other electrode functions as a cathode. The following describes an example in which the pixel electrode functions as the anode and the common electrode functions as the cathode. In other words, by applying a reverse bias between the pixel electrode and the common electrode, the light-receiving device can detect light incident on the light-receiving device, generate electric charges, and extract them as a current.

[0367] The same manufacturing method as for the light-emitting device can be applied to the light-receiving device. The island-shaped active layer (also called photoelectric conversion layer) of the light-receiving device is not formed by a metal mask pattern, but is formed by forming a film that will become the active layer on the entire surface and then processing it, so the island-shaped active layer can be formed with a uniform thickness. In addition, by providing a sacrificial layer on the active layer, damage to the active layer during the manufacturing process of the display device can be reduced, and the reliability of the light-receiving device can be improved.

[0368] Here, a layer shared by a light-receiving device and a light-emitting device may have different functions in the light-emitting device and in the light-receiving device. In this specification, components may be referred to based on their functions in the light-emitting device. For example, a hole injection layer functions 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 an electron injection layer in the light-emitting device and as an electron transport layer in the light-receiving device. Furthermore, a layer shared by a light-receiving device and a light-emitting device may have the same functions in the light-emitting device and in the light-receiving device. For example, a hole transport layer functions as a hole transport layer in both the light-emitting device and the light-receiving device, and an electron transport layer functions as an electron transport layer in both the light-emitting device and the light-receiving device.

[0369] The active layer of the light-receiving device includes a semiconductor. Examples of the semiconductor include inorganic semiconductors such as silicon and organic semiconductors containing organic compounds. In this embodiment, an example in which an organic semiconductor is used as the semiconductor of the active layer is shown. By using an organic semiconductor, the light-emitting layer and the active layer can be formed by the same method (for example, vacuum deposition), which is preferable because it allows the use of a common manufacturing device.

[0370] The active layer is made of n-type semiconductor material, such as fullerene (e.g., C 60 , C 70 Examples of electron-accepting organic semiconductor materials include fullerene derivatives and other fullerenes. Fullerenes have a soccer ball-like shape, which is energetically stable. Fullerenes have deep (low) HOMO and LUMO levels. Because fullerenes have a deep LUMO level, they have extremely high electron-accepting (acceptor) properties. Normally, when the π-electron conjugation (resonance) spreads on a plane, as in benzene, the electron-donating (donor) properties increase, but because fullerenes have a spherical shape, they have high electron-accepting properties despite the large spread of π-electrons. High electron-accepting properties allow charge separation to occur quickly and efficiently, making them useful as light-receiving devices. C 60 , C 70Both have a wide absorption band in the visible light region, especially C 70 is C 60 It is preferable because it has a larger π-electron conjugated system and a wide absorption band in the long wavelength region compared to [6,6]-Phenyl-C 71 -butyric acid methyl ester (abbreviation: PC70BM), [6,6]-Phenyl-C 61 -butyric acid methyl ester (abbreviation: PC60BM), 1',1'',4',4''-Tetrahydro-di[1,4]methanonaphthaleno[1,2:2',3',56,60:2'',3''][5,6]fulrerene-C 60 (abbreviated as ICBA) and others.

[0371] Furthermore, examples of n-type semiconductor materials include metal complexes having a quinoline skeleton, metal complexes having a benzoquinoline skeleton, metal complexes having an oxazole skeleton, metal complexes having a thiazole skeleton, oxadiazole derivatives, triazole derivatives, imidazole derivatives, oxazole derivatives, thiazole derivatives, phenanthroline derivatives, quinoline derivatives, benzoquinoline derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, naphthalene derivatives, anthracene derivatives, coumarin derivatives, rhodamine derivatives, triazine derivatives, and quinone derivatives.

[0372] Examples of p-type semiconductor materials for the active layer include electron-donating organic semiconductor materials such as copper(II) phthalocyanine (CuPc), tetraphenyldibenzoperiflanthene (DBP), zinc phthalocyanine (ZnPc), tin phthalocyanine (SnPc), and quinacridone.

[0373] Examples of p-type semiconductor materials include carbazole derivatives, thiophene derivatives, furan derivatives, compounds having an aromatic amine skeleton, etc. Examples of p-type semiconductor materials include naphthalene derivatives, anthracene derivatives, pyrene derivatives, triphenylene derivatives, fluorene derivatives, pyrrole derivatives, benzofuran derivatives, benzothiophene derivatives, indole derivatives, dibenzofuran derivatives, dibenzothiophene derivatives, indolocarbazole derivatives, porphyrin derivatives, phthalocyanine derivatives, naphthalocyanine derivatives, quinacridone derivatives, polyphenylenevinylene derivatives, polyparaphenylene derivatives, polyfluorene derivatives, polyvinylcarbazole derivatives, polythiophene derivatives, etc.

[0374] The HOMO level of the electron-donating organic semiconductor material is preferably shallower (higher) than the HOMO level of the electron-accepting organic semiconductor material, and the LUMO level of the electron-donating organic semiconductor material is preferably shallower (higher) than the LUMO level of the electron-accepting organic semiconductor material.

[0375] It is preferable to use a spherical fullerene as the electron-accepting organic semiconductor material and a planar organic semiconductor material as the electron-donating organic semiconductor material. Molecules with similar shapes tend to aggregate together, and when molecules of the same type aggregate, the energy levels of their molecular orbitals become close, which can improve carrier transport properties.

[0376] For example, the active layer is preferably formed by co-evaporating an n-type semiconductor and a p-type semiconductor, or may be formed by laminating an n-type semiconductor and a p-type semiconductor.

[0377] The light-receiving device may further include, as a layer other than the active layer, a layer containing a substance with high hole-transporting properties, a substance with high electron-transporting properties, a bipolar substance (a substance with high electron-transporting properties and high hole-transporting properties), etc. Furthermore, without being limited to the above, the light-receiving device may further include a layer containing a substance with high hole-injecting properties, a hole-blocking material, a material with high electron-injecting properties, an electron-blocking material, etc.

[0378] The light-receiving device can be made of either a low-molecular-weight compound or a high-molecular-weight compound, and may contain an inorganic compound. The layers constituting the light-receiving device can be formed by a method such as vapor deposition (including vacuum deposition), transfer, printing, inkjet, or coating.

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

[0380] In addition, the active layer can be made of a polymer compound such as Poly[[4,8-bis[5-(2-ethylhexyl)-2-thienyl]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl]-2,5-thiophenediyl[5,7-bis(2-ethylhexyl)-4,8-dioxo-4H,8H-benzo[1,2-c:4,5-c']dithiophene-1,3-diyl]]polymer (abbreviated as PBDB-T) or a PBDB-T derivative, which functions as a donor. For example, an acceptor material can be dispersed in PBDB-T or a PBDB-T derivative.

[0381] The active layer may also contain a mixture of three or more materials. For example, to expand the wavelength range, a third material may be mixed in addition to an n-type semiconductor material and a p-type semiconductor material. In this case, the third material may be a low-molecular-weight compound or a high-molecular-weight compound.

[0382] This concludes the description of the light receiving device.

[0383] FIG. 18E shows an example of a pixel circuit of a sub-pixel having a light-receiving device, and FIG. 18F shows an example of a pixel circuit of a sub-pixel having a light-emitting device.

[0384] 18E includes a light receiving device PD, a transistor M11, a transistor M12, a transistor M13, a transistor M14, and a capacitance element C2. Here, an example is shown in which a photodiode is used as the light receiving device PD.

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

[0386] A constant potential is supplied to the wiring V1, wiring V2, and wiring V3. When the light-receiving device PD is driven in reverse bias, a potential lower than the potential of the wiring V1 is supplied to the wiring V2. The transistor M12 is controlled by a signal supplied to the wiring RES and has a function of resetting the potential of a node connected to the gate of the transistor M13 to the potential supplied to the wiring V2. The transistor M11 is controlled by a signal supplied to the wiring TX and has a function of controlling the timing at which the potential of the node changes depending on the current flowing through the light-receiving device PD. The transistor M13 functions as an amplifying transistor that outputs according to the potential of the node. The transistor M14 is controlled by a signal supplied to the wiring SE and functions as a selection transistor that reads out the output according to the potential of the node to an external circuit connected to the wiring OUT1.

[0387] 18F includes a light-emitting device EL, a transistor M15, a transistor M16, a transistor M17, and a capacitor C3. Here, a light-emitting diode is used as the light-emitting device EL. It is particularly preferable to use an organic EL element as the light-emitting device EL.

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

[0389] A constant potential is supplied to the wiring V4 and the wiring V5. The anode side of the light-emitting device EL can be set to a high potential, and the cathode side can be set to a lower potential than the anode side. The transistor M15 is controlled by a signal supplied to the wiring VG and functions as a selection transistor for controlling the selection state of the pixel circuit PIX2. The transistor M16 also functions as a drive transistor that controls the current flowing through the light-emitting device EL depending on the potential supplied to its gate. When the transistor M15 is in a conductive state, the potential supplied to the wiring VS is supplied to the gate of the transistor M16, and the light emission brightness of the light-emitting device EL can be controlled depending on the potential. The transistor M17 is controlled by a signal supplied to the wiring MS and has the function of outputting the potential between the transistor M16 and the light-emitting device EL to the outside via the wiring OUT2.

[0390] In the display panel of this embodiment, an image may be displayed by pulsating the light-emitting elements. By shortening the driving time of the light-emitting elements, it is possible to reduce the power consumption and heat generation of the display panel. In particular, organic EL elements are suitable because of their excellent frequency characteristics. The frequency can be, for example, 1 kHz or more and 100 MHz or less.

[0391] Here, it is preferable that 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 transistors that use a metal oxide (oxide semiconductor) in the semiconductor layer in which the channel is formed.

[0392] A transistor using a metal oxide, which has a wider band gap and a lower carrier density than silicon, can achieve an extremely small off-state current. Therefore, the small off-state current allows charge stored in a capacitor connected in series with the transistor to be held for a long period of time. Therefore, it is preferable to use a transistor including an oxide semiconductor for the transistor M11, the transistor M12, and the transistor M15, which are connected in series with the capacitor C2 or the capacitor C3. Furthermore, by using a transistor including an oxide semiconductor for other transistors as well, manufacturing costs can be reduced.

[0393] Alternatively, the transistors M11 to M17 may be transistors in which silicon is used as a semiconductor in which a channel is formed. In particular, using silicon with high crystallinity, such as single crystal silicon or polycrystalline silicon, is preferable because high field-effect mobility can be achieved and higher-speed operation is possible.

[0394] Alternatively, a structure may be used in which at least one of the transistors M11 to M17 includes an oxide semiconductor and the remaining transistors include silicon.

[0395] Although the transistors are shown as n-channel transistors in FIGS. 18E and 18F, p-channel transistors can also be used.

[0396] The transistors of the pixel circuit PIX1 and the transistors of the pixel circuit PIX2 are preferably formed side by side on the same substrate. In particular, it is preferable that the transistors of the pixel circuit PIX1 and the transistors of the pixel circuit PIX2 are mixed and periodically arranged in one region.

[0397] It is also preferable to provide one or more layers having transistors and / or capacitors at positions overlapping the light-receiving device PD or the light-emitting device EL, thereby reducing the effective area occupied by each pixel circuit and realizing a high-definition light-receiving section or display section.

[0398] As described above, the display device of this embodiment can add two functions in addition to the display function by incorporating two types of light-receiving devices in one pixel, thereby enabling the display device to have multiple functions. For example, a high-resolution imaging function and a sensing function such as a touch sensor or near-touch sensor can be realized. Furthermore, by combining a pixel incorporating two types of light-receiving devices with a pixel having a different configuration, the functions of the display device can be further increased. For example, a pixel having a light-emitting device that emits infrared light or various sensor devices can be used.

[0399] (Embodiment 6) In this embodiment, a high-definition display device will be described.

[0400] [Display panel configuration example] Wearable electronic devices for VR, AR, and other applications can provide 3D images by using parallax. In this case, it is necessary to display an image for the right eye within the field of view of the right eye, and an image for the left eye within the field of view of the left eye. Here, the shape of the display unit of the display device may be a horizontally long rectangle, but pixels located outside the fields of view of the right and left eyes do not contribute to the display, so those pixels always display black.

[0401] Therefore, it is preferable to divide the display section of the display panel into two areas, one for the right eye and one for the left eye, and not place pixels in the outer area that does not contribute to display. This reduces the power consumption required to write pixels. Also, since the load on the source lines, gate lines, etc. is reduced, a high frame rate display becomes possible. This allows for smoother video display, enhancing the sense of realism.

[0402] Fig. 19A shows an example of the configuration of a display panel. In Fig. 19A, a display unit 702L for the left eye and a display unit 702R for the right eye are arranged inside a substrate 701. In addition to the display units 702L and 702R, a drive circuit, wiring, an IC, an FPC, and the like may also be arranged on the substrate 701.

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

[0404] The top surface shape of display unit 702L and display unit 702R may also be another regular polygon. FIG. 19B shows an example of a regular hexagon, FIG. 19C shows an example of a regular octagon, FIG. 19D shows an example of a regular decagon, and FIG. 19E shows an example of a regular dodecagon. In this way, by using a polygon with an even number of corners, the shape of the display unit can be made symmetrical. Note that polygons that are not regular polygons may also be used. Also, regular polygons or polygons with rounded corners may be used.

[0405] Since the display unit is made up of pixels arranged in a matrix, the straight line portions of the outline of each display unit may not be straight lines in the strict sense, but may have stepped portions. In particular, straight line portions that are not parallel to the pixel arrangement direction will have a stepped top surface shape. However, since the user does not see the pixel shapes when viewing, even if the diagonal outline of the display unit is strictly stepped, it can be considered to be a straight line. Similarly, even if the curved portion of the outline of the display unit is strictly stepped, it can be considered to be a curve.

[0406] FIG. 19F shows an example in which the top surfaces of display units 702L and 702R are circular.

[0407] Furthermore, the top surface shapes of the display units 702L and 702R may be asymmetrical, and may not be regular polygons.

[0408] FIG. 19G shows an example in which the top surface shapes of display units 702L and 702R are asymmetrical octagons. FIG. 19H shows an example in which the top surface shapes of display units 702L and 702R are asymmetrical. Even when the top surfaces of display units 702L and 702R are asymmetrical, it is preferable that display units 702L and 702R be symmetrically positioned. This allows for a natural image to be displayed.

[0409] Although the above description has been given of a configuration in which the display section is divided into two, it may be formed as a continuous shape.

[0410] Fig. 19I shows an example in which the two circular display units in Fig. 19F are connected together, and Fig. 19J shows an example in which the two regular octagonal display units in Fig. 19C are connected together.

[0411] The above is a description of an example of the configuration of the display panel.

[0412] At least a part of the configuration examples exemplified in this embodiment and the corresponding drawings can be combined as appropriate with other configuration examples or drawings.

[0413] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0414] (Embodiment 7) In this embodiment, a metal oxide (also referred to as an oxide semiconductor) that can be used for the OS transistor described in the above embodiment will be described.

[0415] The metal oxide used in the OS transistor preferably contains at least indium or zinc, and more preferably contains indium and zinc. For example, the metal oxide preferably contains indium, M (where M is one or more selected from 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 one or more selected from gallium, aluminum, yttrium, and tin, and more preferably gallium.

[0416] Furthermore, the metal oxide can be formed by a sputtering method, a chemical vapor deposition (CVD) method such as a metal organic chemical vapor deposition (MOCVD) method, or an atomic layer deposition (ALD) method.

[0417] Hereinafter, an oxide containing indium (In), gallium (Ga), and zinc (Zn) will be described as an example of a metal oxide. Note that an oxide containing indium (In), gallium (Ga), and zinc (Zn) may be referred to as an In-Ga-Zn oxide.

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

[0419] The crystalline structure of a film or substrate can be evaluated using an X-ray diffraction (XRD) spectrum. For example, it can be evaluated using an XRD spectrum obtained by GIXD (Grazing-Incidence XRD) measurement. The GIXD method is also called the thin film method or the Seemann-Bohlin method. In the following, the XRD spectrum obtained by GIXD measurement may be simply referred to as the XRD spectrum.

[0420] For example, in the case of a quartz glass substrate, the peak shape of the XRD spectrum is nearly symmetrical. On the other hand, in the case of an In-Ga-Zn oxide film having a crystalline structure, the peak shape of the XRD spectrum is asymmetrical. The asymmetrical peak shape of the XRD spectrum clearly indicates the presence of crystals in the film or substrate. In other words, if the peak shape of the XRD spectrum is not symmetrical, the film or substrate cannot be said to be in an amorphous state.

[0421] The crystalline structure of a film or substrate can be evaluated by a diffraction pattern (also called a nanobeam electron diffraction pattern) observed by nanobeam electron diffraction (NBED). For example, a halo is observed in the diffraction pattern of a quartz glass substrate, confirming that the quartz glass is in an amorphous state. Furthermore, a spot-like pattern is observed in the diffraction pattern of an In-Ga-Zn oxide film formed at room temperature, rather than a halo. Therefore, it is presumed that an In-Ga-Zn oxide film formed at room temperature is neither single-crystal nor polycrystalline, nor in an amorphous state, but is in an intermediate state, and it cannot be concluded that it is in an amorphous state.

[0422] <<Oxide semiconductor structure>> Note that oxide semiconductors may be classified differently from the above when focusing on their structures. For example, oxide semiconductors are divided into single-crystal oxide semiconductors and other non-single-crystal oxide semiconductors. Examples of non-single-crystal oxide semiconductors include the above-mentioned CAAC-OS and nc-OS. Non-single-crystal oxide semiconductors include polycrystalline oxide semiconductors, amorphous-like oxide semiconductors (a-like OSs), amorphous oxide semiconductors, and the like.

[0423] Here, the above-mentioned CAAC-OS, nc-OS, and a-like OS will be described in detail.

[0424] [CAAC-OS] CAAC-OS is an oxide semiconductor having multiple crystalline regions, each with its c-axis aligned in a specific direction. The specific direction can be the thickness direction of the CAAC-OS film, the normal direction to the surface on which the CAAC-OS film is formed, or the normal direction to the surface of the CAAC-OS film. A crystalline region is a region with periodic atomic arrangement. If the atomic arrangement is considered as a lattice arrangement, a crystalline region can also be a region with a uniform lattice arrangement. Furthermore, CAAC-OS has a region where multiple crystalline regions are connected in the ab-plane direction, and the region may have distortion. Note that distortion refers to a location where the lattice arrangement changes between a region with a uniform lattice arrangement and a region with a different uniform lattice arrangement in the region where multiple crystalline regions are connected. In other words, CAAC-OS is an oxide semiconductor with a c-axis aligned but no clear orientation in the ab-plane direction.

[0425] Each of the multiple crystalline regions is composed of one or more minute crystals (crystals with a maximum diameter of less than 10 nm). When a crystalline region is composed of one minute crystal, the maximum diameter of the crystalline region is less than 10 nm. When a crystalline region is composed of many minute crystals, the size of the crystalline region may be several tens of nm.

[0426] In the In-Ga-Zn oxide, the CAAC-OS tends to have a layered crystal structure (also referred to as a layered structure) in which a layer containing indium (In) and oxygen (hereinafter referred to as an In layer) and a layer containing gallium (Ga), zinc (Zn), and oxygen (hereinafter referred to as a (Ga,Zn) layer) are stacked. Note that indium and gallium are mutually substituted. Therefore, the (Ga,Zn) layer may contain indium. The In layer may contain gallium. The In layer may contain zinc. The layered structure is observed as a lattice image in a high-resolution transmission electron microscope (TEM) image, for example.

[0427] When the CAAC-OS film is subjected to structural analysis using, for example, an XRD apparatus, a peak indicating c-axis orientation is detected at or near 2θ=31° in out-of-plane XRD measurement using θ / 2θ scan. Note that the position of the peak indicating c-axis orientation (2θ value) may vary depending on the type and composition of the metallic elements constituting the CAAC-OS.

[0428] For example, in the electron diffraction pattern of a CAAC-OS film, multiple bright spots are observed, and the spots are observed at positions that are point-symmetric with respect to the spot of the incident electron beam that has passed through the sample (also called the direct spot).

[0429] When the crystalline region is observed from the specific direction, the lattice arrangement within the crystalline region is basically a hexagonal lattice, but the unit cell is not necessarily a regular hexagon and may be non-regular hexagonal. The distortion may also have a pentagonal, heptagonal, or other lattice arrangement. In the CAAC-OS, no clear grain boundaries are observed even near the distortion. This indicates that the formation of grain boundaries is suppressed by the distortion of the lattice arrangement. This is thought to be because the CAAC-OS can tolerate distortion due to the lack of close-packed oxygen atom arrangement in the ab-plane direction and the change in interatomic bond distance caused by metal atom substitution.

[0430] A crystal structure with clear grain boundaries is called polycrystalline. Grain boundaries act as recombination centers, trapping carriers and potentially causing a decrease in the on-state current and field-effect mobility of a transistor. Therefore, CAAC-OS, which lacks clear grain boundaries, is one of the crystalline oxides with a crystal structure suitable for use in the semiconductor layer of a transistor. Zn is preferred for use in CAAC-OS. For example, In-Zn oxide and In-Ga-Zn oxide are suitable because they can suppress the generation of grain boundaries more effectively than In oxide.

[0431] CAAC-OS is an oxide semiconductor with high crystallinity and no clear crystal grain boundaries. Therefore, it can be said that the CAAC-OS is less susceptible to a decrease in electron mobility due to crystal grain boundaries. Furthermore, since the crystallinity of an oxide semiconductor can be reduced by impurities or defects, the CAAC-OS can be said to be an oxide semiconductor with few impurities and defects (such as oxygen vacancies). Therefore, oxide semiconductors with CAAC-OS have stable physical properties. Therefore, oxide semiconductors with CAAC-OS are heat-resistant and highly reliable. Furthermore, the CAAC-OS is stable even under high temperatures (so-called thermal budgets) during the manufacturing process. Therefore, using a CAAC-OS for an OS transistor can increase the flexibility of the manufacturing process.

[0432] [nc-OS] The nc-OS has periodic atomic arrangement in a microscopic region (e.g., a region of 1 nm to 10 nm, particularly a region of 1 nm to 3 nm). In other words, the nc-OS has microcrystalline structures. The size of these microcrystalline structures is, for example, 1 nm to 10 nm, particularly 1 nm to 3 nm, and therefore these microcrystalline structures are also called nanocrystalline structures. Furthermore, the nc-OS exhibits no regularity in the crystal orientation between different nanocrystalline structures. Therefore, the entire film lacks orientation. Therefore, depending on the analytical method, the nc-OS may be indistinguishable from an a-like OS or an amorphous oxide semiconductor. For example, when a structural analysis of an nc-OS film is performed using an XRD apparatus, no peaks indicating crystallinity are detected in out-of-plane XRD measurements using θ / 2θ scanning. Furthermore, when an nc-OS film is subjected to electron diffraction (also known as selected-area electron diffraction) using an electron beam with a probe diameter larger than that of nanocrystalline structures (e.g., 50 nm or larger), a halo-like diffraction pattern is observed. On the other hand, when electron diffraction (also called nanobeam electron diffraction) is performed on an nc-OS film using an electron beam with a probe diameter close to or smaller than the size of the nanocrystals (for example, 1 nm to 30 nm), an electron diffraction pattern can be obtained in which multiple spots are observed within a ring-shaped region centered on the direct spot.

[0433] [a-like OS] The a-like OS is an oxide semiconductor having a structure between the nc-OS and the amorphous oxide semiconductor. The a-like OS has a pore or low-density region. That is, the a-like OS has lower crystallinity than the nc-OS and CAAC-OS. Furthermore, the a-like OS has a higher hydrogen concentration in the film than the nc-OS and CAAC-OS.

[0434] <<Oxide semiconductor structure>> Next, the above-mentioned CAC-OS will be described in detail, which relates to the material composition.

[0435] [CAC-OS] CAC-OS is a material structure in which elements constituting a metal oxide are unevenly distributed in a size range of 0.5 nm to 10 nm, preferably 1 nm to 3 nm, or a similar size range. Hereinafter, a metal oxide in which one or more metal elements are unevenly distributed and the regions containing the metal elements are mixed in a size range of 0.5 nm to 10 nm, preferably 1 nm to 3 nm, or a similar size range, is also referred to as a mosaic or patch state.

[0436] Furthermore, CAC-OS has a mosaic structure in which the material is separated into first and second regions, and the first regions are distributed throughout the film (hereinafter also referred to as a cloud structure). That is, CAC-OS is a composite metal oxide having a structure in which the first and second regions are mixed.

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

[0438] Specifically, the first region is a region whose main component is indium oxide, indium zinc oxide, or the like. The second region is a region whose main component is gallium oxide, gallium zinc oxide, or the like. In other words, the first region can be rephrased as a region whose main component is In. The second region can be rephrased as a region whose main component is Ga.

[0439] It should be noted that there are cases where a clear boundary between the first region and the second region cannot be observed.

[0440] In addition, CAC-OS in In-Ga-Zn oxide refers to a material structure containing In, Ga, Zn, and O, in which some regions primarily composed of Ga and other regions primarily composed of In are randomly arranged in a mosaic pattern. Therefore, it is presumed that CAC-OS has a structure in which metal elements are distributed nonuniformly.

[0441] CAC-OS can be formed, for example, by a sputtering method under conditions where the substrate is not intentionally heated. When forming CAC-OS by a sputtering method, any one or more of an inert gas (typically argon), oxygen gas, and nitrogen gas may be used as the deposition gas. The lower the flow rate of oxygen gas relative to the total flow rate of deposition gas during deposition, the better. For example, the flow rate of oxygen gas relative to the total flow rate of deposition gas during deposition is set to 0% or more and less than 30%, preferably 0% or more and 10% or less.

[0442] Furthermore, for example, in the case of CAC-OS in an In-Ga-Zn oxide, EDX mapping obtained using EDX (Energy Dispersive X-ray spectroscopy) confirms that the CAC-OS has a structure in which a region containing In as a main component (first region) and a region containing Ga as a main component (second region) are unevenly distributed and mixed.

[0443] Here, the first region has higher conductivity than the second region. That is, the flow of carriers through the first region causes the metal oxide to exhibit conductivity. Therefore, the first region is distributed in a cloud-like manner in the metal oxide, thereby achieving a high field-effect mobility (μ).

[0444] On the other hand, the second region has higher insulating properties than the first region. That is, the second region is distributed in the metal oxide, thereby suppressing leakage current.

[0445] Therefore, when CAC-OS is used in a transistor, the conductivity due to the first region and the insulating property due to the second region act complementarily, thereby providing the CAC-OS with a switching function (the ability to turn on / off). In other words, CAC-OS has a conductive function in part of the material and an insulating function in part of the material, and the material as a whole functions as a semiconductor. By separating the conductive function from the insulating function, both functions can be maximized. Therefore, by using CAC-OS in a transistor, a high on-current (I on ), high field-effect mobility (μ), and good switching behavior can be achieved.

[0446] Furthermore, a transistor using CAC-OS has high reliability, making it ideal for various semiconductor devices such as display devices.

[0447] Oxide semiconductors have a variety of structures, each with different characteristics. The oxide semiconductor of one embodiment of the present invention may include two or more of an amorphous oxide semiconductor, a polycrystalline oxide semiconductor, an a-like OS, a CAC-OS, an nc-OS, and a CAAC-OS.

[0448] <Transistors containing oxide semiconductors> Next, a case where the oxide semiconductor is used in a transistor will be described.

[0449] By using the oxide semiconductor for a transistor, a transistor with high field-effect mobility and high reliability can be realized.

[0450] For the transistor, an oxide semiconductor with a low carrier concentration is preferably used. For example, the carrier concentration of the oxide semiconductor is 1×10 17 cm -3 Less than 1 × 10 15 cm -3 or less, more preferably 1 × 10 13 cm -3 Less than or equal to 1×10 11 cm -3 or less, more preferably 1 × 10 10 cm -3 Less than 1 x 10 -9 cm -3 That is all. Note that in order to reduce the carrier concentration of an oxide semiconductor film, the impurity concentration in the oxide semiconductor film may be reduced to reduce the density of defect states. In this specification and the like, a semiconductor having a low impurity concentration and a low density of defect states is referred to as a highly purified intrinsic or substantially highly purified intrinsic oxide semiconductor. Note that an oxide semiconductor having a low carrier concentration may also be referred to as a highly purified intrinsic or substantially highly purified intrinsic oxide semiconductor.

[0451] Furthermore, a highly purified intrinsic or substantially highly purified intrinsic oxide semiconductor film has a low density of defect states, and therefore the density of trap states may also be low.

[0452] Furthermore, charges trapped in the trap states of an oxide semiconductor take a long time to dissipate and may behave like fixed charges. Therefore, a transistor in which a channel formation region is formed in an oxide semiconductor with a high density of trap states may have unstable electrical characteristics.

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

[0454] <Impurities> Here, the influence of each impurity in an oxide semiconductor will be described.

[0455] When an oxide semiconductor contains silicon or carbon, which is one of the Group 14 elements, defect levels are formed in the oxide semiconductor. Therefore, the concentration of silicon or carbon in the oxide semiconductor and the concentration of silicon or carbon near the interface with the oxide semiconductor (concentration obtained by secondary ion mass spectrometry (SIMS)) are calculated to be 2×10 18 atoms / cm 3 Less than or equal to 2 x 10 17 atoms / cm 3 The following applies.

[0456] Furthermore, when an oxide semiconductor contains an alkali metal or alkaline earth metal, defect levels may be formed and carriers may be generated. Therefore, a transistor using an oxide semiconductor containing an alkali metal or alkaline earth metal is likely to have normally-on characteristics. Therefore, when the concentration of the alkali metal or alkaline earth metal in the oxide semiconductor obtained by SIMS is 1×10 18 atoms / cm 3 Less than or equal to 2 x 10 16 atoms / cm 3 Do the following:

[0457] Furthermore, when nitrogen is contained in an oxide semiconductor, electrons serving as carriers are generated, the carrier concentration increases, and the semiconductor is likely to become n-type. As a result, a transistor using an oxide semiconductor containing nitrogen as a semiconductor tends to have normally-on characteristics. Alternatively, when nitrogen is contained in an oxide semiconductor, trap states may be formed. As a result, the electrical characteristics of the transistor may become unstable. For this reason, the nitrogen concentration in the oxide semiconductor obtained by SIMS is set to 5×10 19 atoms / cm 3 Less than 5 x 10 18 atoms / cm3 Less than or equal to 1×10 18 atoms / cm 3 Less than 5 × 10, more preferably 17 atoms / cm 3 Do the following:

[0458] Furthermore, hydrogen contained in an oxide semiconductor may react with oxygen bonded to a metal atom to form water, which may form an oxygen vacancy. When hydrogen enters the oxygen vacancy, electrons serving as carriers may be generated. Furthermore, some of the hydrogen may bond with oxygen bonded to a metal atom to generate electrons serving as carriers. Therefore, a transistor using an oxide semiconductor containing hydrogen is likely to have normally-on characteristics. For this reason, it is preferable to reduce the amount of hydrogen in the oxide semiconductor as much as possible. Specifically, the hydrogen concentration in the oxide semiconductor obtained by SIMS is measured to be 1×10 20 atoms / cm 3 Less than 1 x 10 19 atoms / cm 3 less than 5 × 10 18 atoms / cm 3 less than 1×10 18 atoms / cm 3 Make it less than.

[0459] When an oxide semiconductor with sufficiently reduced impurities is used for a channel formation region of a transistor, stable electrical characteristics can be obtained.

[0460] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0461] (Embodiment 8) In this embodiment, electronic devices of one embodiment of the present invention will be described with reference to FIGS.

[0462] The electronic devices of this embodiment include the display device of one embodiment of the present invention. The display device of one embodiment of the present invention can easily achieve high definition, high resolution, and a large size. Therefore, the display device of one embodiment of the present invention can be used as a display portion of various electronic devices.

[0463] Furthermore, the display device of one embodiment of the present invention can be manufactured at low cost, which leads to a reduction in the manufacturing cost of electronic devices.

[0464] Examples of electronic devices include electronic devices with relatively large screens such as television sets, desktop or notebook personal computers, computer monitors, digital signage, large game machines such as pachinko machines, as well as digital cameras, digital video cameras, digital photo frames, mobile phones, portable game machines, personal digital assistants, and sound playback devices.

[0465] In particular, the display device of one embodiment of the present invention can achieve high resolution and can therefore be suitably used in electronic devices having a relatively small display portion. Examples of such electronic devices include information terminals (wearable devices) such as wristwatches and bracelets, as well as head-mounted wearable devices such as VR devices and eyeglass-type AR devices. Examples of wearable devices include devices for substitutional reality (SR) and mixed reality (MR).

[0466] The display device of one embodiment of the present invention preferably has an 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), or 8K4K (7680 × 4320 pixels). A resolution of 4K2K, 8K4K, or higher is particularly preferable. Furthermore, the pixel density (resolution) of the display device of one embodiment of the present invention is preferably 300 ppi or higher, more preferably 500 ppi or higher, more preferably 1000 ppi or higher, more preferably 2000 ppi or higher, more preferably 3000 ppi or higher, more preferably 5000 ppi or higher, and even more preferably 7000 ppi or higher. By using a display device with such high resolution or high definition, it is possible to further enhance the sense of presence and depth in electronic devices for personal use such as portable or home use.

[0467] The electronic device of this embodiment can be incorporated along the curved surface of the inner or outer wall of a house or building, or the interior or exterior of an automobile.

[0468] The electronic device of this embodiment may have an antenna. By receiving a signal through the antenna, images, information, and the like can be displayed on a display portion. In addition, when the electronic device has an antenna and a secondary battery, the antenna may be used for contactless power transmission.

[0469] The electronic device of this embodiment may have a sensor (including the function of sensing, detecting, or measuring force, displacement, position, velocity, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared light).

[0470] The electronic device of the present embodiment can have various functions, such as a function to display various information (still images, videos, text images, etc.) on a display unit, a touch panel function, a function to display a calendar, date, time, etc., a function to execute various software (programs), a wireless communication function, a function to read out programs or data recorded on a recording medium, etc.

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

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

[0473] The display device of one embodiment of the present invention can be applied to the display portion 6502.

[0474] FIG. 20B is a schematic cross-sectional view including the end of the housing 6501 on the microphone 6506 side.

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

[0476] A display panel 6511, an optical member 6512, and a touch sensor panel 6513 are fixed to the protective member 6510 by adhesive layers (not shown).

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

[0478] The flexible display (flexible display device) of one embodiment of the present invention can be applied to the display panel 6511. Therefore, an extremely lightweight electronic device can be realized. In addition, since the display panel 6511 is extremely thin, a large-capacity battery 6518 can be mounted thereon while keeping the thickness of the electronic device small. Furthermore, by folding back a part of the display panel 6511 and arranging a connection portion with the FPC 6515 on the back side of the pixel portion, an electronic device with a narrow frame can be realized.

[0479] 21A shows an example of a television device. A television device 7100 has a display unit 7000 built into a housing 7101. Here, the housing 7101 is supported by a stand 7103.

[0480] The display device of one embodiment of the present invention can be applied to the display portion 7000.

[0481] 21A can be operated using operation switches provided on the housing 7101 and a separate remote control 7111. Alternatively, a touch sensor may be provided in the display unit 7000, and the television 7100 may be operated by touching the display unit 7000 with a finger or the like. The remote control 7111 may have a display unit that displays information output from the remote control 7111. The channel and volume can be controlled using operation keys or a touch panel provided on the remote control 7111, and the video displayed on the display unit 7000 can be controlled.

[0482] The television device 7100 is configured to include a receiver, a modem, and the like. The receiver can receive general television broadcasts. In addition, by connecting to a wired or wireless communication network via the modem, it is possible to perform one-way (from sender to receiver) or two-way (between sender and receiver, or between receivers, etc.) information communication.

[0483] 21B shows an example of a laptop personal computer 7200. The laptop personal computer 7200 includes a housing 7211, a keyboard 7212, a pointing device 7213, and an external connection port 7214. The housing 7211 includes a display portion 7000.

[0484] The display device of one embodiment of the present invention can be applied to the display portion 7000.

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

[0486] 21C includes a housing 7301, a display unit 7000, and a speaker 7303. The digital signage 7300 may further include an LED lamp, operation keys (including a power switch or an operation switch), a connection terminal, various sensors, a microphone, and the like.

[0487] 21D shows a digital signage 7400 attached to a cylindrical pillar 7401. The digital signage 7400 has a display unit 7000 provided along the curved surface of the pillar 7401.

[0488] 21C and 21D, the display device of one embodiment of the present invention can be applied to the display portion 7000.

[0489] The larger the display unit 7000, the more information can be provided at one time. Also, the larger the display unit 7000, the more easily it will attract people's attention, which can increase the advertising effectiveness of, for example, advertisements.

[0490] Applying a touch panel to the display unit 7000 is preferable because it not only displays images or videos on the display unit 7000 but also allows the user to intuitively operate it. Furthermore, when used to provide information such as route information or traffic information, intuitive operation can improve usability.

[0491] 21C and 21D, it is preferable that the digital signage 7300 or the digital signage 7400 can be linked via wireless communication with an information terminal 7311 or an information terminal 7411 such as a smartphone carried by a user. For example, advertising information displayed on the display unit 7000 can be displayed on the screen of the information terminal 7311 or the information terminal 7411. Furthermore, the display on the display unit 7000 can be switched by operating the information terminal 7311 or the information terminal 7411.

[0492] Furthermore, it is also possible to cause the digital signage 7300 or the digital signage 7400 to execute a game using the screen of the information terminal 7311 or the information terminal 7411 as an operation means (controller), thereby allowing an unspecified number of users to simultaneously participate in and enjoy the game.

[0493] FIG. 22A is a diagram showing the appearance of the camera 8000 with the viewfinder 8100 attached.

[0494] The camera 8000 includes a housing 8001, a display unit 8002, operation buttons 8003, a shutter button 8004, etc. A detachable lens 8006 is attached to the camera 8000. Note that the lens 8006 and the housing 8001 of the camera 8000 may be integrated together.

[0495] The camera 8000 can capture an image by pressing a shutter button 8004 or touching a display unit 8002 that functions as a touch panel.

[0496] The housing 8001 has a mount with electrodes, and can be connected to a finder 8100 as well as a strobe device and the like.

[0497] The finder 8100 includes a housing 8101, a display portion 8102, a button 8103, and the like.

[0498] The housing 8101 is attached to the camera 8000 by a mount that engages with the mount of the camera 8000. The viewfinder 8100 can display an image received from the camera 8000 on a display unit 8102.

[0499] The button 8103 has a function such as a power button.

[0500] The display device of one embodiment of the present invention can be applied to a display portion 8002 of a camera 8000 and a display portion 8102 of a finder 8100. Note that the camera 8000 may have a built-in finder.

[0501] FIG. 22B is a diagram showing the appearance of the head mounted display 8200.

[0502] The head-mounted display 8200 includes a mounting portion 8201, a lens 8202, a main body 8203, a display portion 8204, and a cable 8205. The mounting portion 8201 has a built-in battery 8206.

[0503] A cable 8205 supplies power from a battery 8206 to the main body 8203. The main body 8203 includes a wireless receiver or the like, and can display received video information on a display portion 8204. The main body 8203 also includes a camera, and can use information on the movement of the user's eyeballs or eyelids as an input means.

[0504] The wearing unit 8201 may have a function of recognizing the line of sight by providing a plurality of electrodes at positions that come into contact with the user, capable of detecting a current that flows in accordance with the movement of the user's eyeballs. The wearing unit 8201 may also have a function of monitoring the user's pulse rate based on the current that flows through the electrodes. The wearing unit 8201 may also have various sensors, such as a temperature sensor, a pressure sensor, and an acceleration sensor, and may also have a function of displaying the user's biological information on the display unit 8204 and a function of changing the image displayed on the display unit 8204 in accordance with the movement of the user's head.

[0505] The display device of one embodiment of the present invention can be applied to the display portion 8204.

[0506] 22C to 22E are diagrams showing the appearance of a head mounted display 8300. The head mounted display 8300 includes a housing 8301, a display portion 8302, a band-shaped fixture 8304, and a pair of lenses 8305.

[0507] A user can view the display on the display portion 8302 through the lens 8305. Note that it is preferable to arrange the display portion 8302 in a curved manner because the user can feel a high sense of presence. In addition, by viewing different images displayed in different regions of the display portion 8302 through the lens 8305, it is possible to perform 3D display using parallax. Note that the present invention is not limited to a configuration in which one display portion 8302 is provided, and two display portions 8302 may be provided, with one display portion being provided for each eye of the user.

[0508] The display device of one embodiment of the present invention can be applied to the display portion 8302. The display device of one embodiment of the present invention can also achieve extremely high resolution. For example, even when the display is enlarged and viewed using the lens 8305 as shown in FIG. 22E, the pixels are hardly visible to the user. That is, the display portion 8302 allows the user to view a highly realistic image.

[0509] 22F is a diagram showing the appearance of a goggle-type head-mounted display 8400. The head-mounted display 8400 includes a pair of housings 8401, a mounting portion 8402, and a cushioning member 8403. A display portion 8404 and a lens 8405 are provided in each of the pair of housings 8401. By displaying different images on the pair of display portions 8404, a 3D display using parallax can be performed.

[0510] A user can view the display portion 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 eyesight. The display portion 8404 is preferably a square or a horizontally long rectangle. This can enhance the sense of realism.

[0511] The wearing part 8402 is preferably adjustable to fit the size of the user's face and has plasticity and elasticity to prevent it from slipping off. Furthermore, a part of the wearing part 8402 preferably has a vibration mechanism that functions as a bone conduction earphone. This allows the user to enjoy video and audio simply by wearing the earphone, without the need for separate audio equipment such as earphones or speakers. The housing 8401 may also have a function to output audio data via wireless communication.

[0512] The mounting unit 8402 and the buffer member 8403 are portions that come into contact with the user's face (forehead, cheeks, etc.). The close contact of the buffer member 8403 with the user's face can prevent light leakage and enhance the sense of immersion. The buffer member 8403 is preferably made of a soft material so that it can be in close contact with the user's face when the user wears the head-mounted display 8400. For example, materials such as rubber, silicone rubber, urethane, and sponge can be used. Furthermore, using a sponge or the like with its surface covered with cloth or leather (natural leather or synthetic leather) can prevent gaps from forming between the user's face and the buffer member 8403, thereby effectively preventing light leakage. Furthermore, using such materials is preferable because they feel pleasant to the touch and do not cause the user to feel cold when worn in cold seasons. It is preferable that components that come into contact with the user's skin, such as the buffer member 8403 or the mounting unit 8402, be removable for easy cleaning or replacement.

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

[0514] 23A to 23F have various functions. For example, they may have a function to display various information (still images, videos, text images, etc.) on a display unit, a touch panel function, a function to display a calendar, date, or time, a function to control processing using various software (programs), a wireless communication function, a function to read and process programs or data recorded on a recording medium, etc. Note that the functions of the electronic device are not limited to these, and the electronic device may have various other functions. The electronic device may have multiple display units. Furthermore, the electronic device may have a function to include a camera or the like to capture still images or videos and store them on a recording medium (external or built-in to the camera), a function to display the captured images on the display unit, etc.

[0515] The display device of one embodiment of the present invention can be applied to the display portion 9001 .

[0516] The electronic device shown in FIGS. 23A to 23F will be described in detail below.

[0517] FIG. 23A is a perspective view showing a mobile information terminal 9101. The mobile information terminal 9101 can be used as, for example, a smartphone. The mobile information terminal 9101 may be provided with a speaker 9003, a connection terminal 9006, a sensor 9007, and the like. The mobile information terminal 9101 can display text and image information on multiple surfaces thereof. FIG. 23A shows an example in which three icons 9050 are displayed. Information 9051, indicated by a dashed rectangle, can also be displayed on another surface of the display unit 9001. Examples of the information 9051 include notifications of incoming emails, SNS messages, phone calls, etc., the title of the email or SNS message, the sender's name, the date and time, the remaining battery level, and the strength of antenna reception. Alternatively, the icon 9050 or the like may be displayed in the position where the information 9051 is displayed.

[0518] 23B is a perspective view showing mobile information terminal 9102. Mobile information terminal 9102 has a function of displaying information on three or more sides of display unit 9001. Here, an example is shown in which information 9052, information 9053, and information 9054 are displayed on different sides. For example, while carrying mobile information terminal 9102 in a breast pocket of clothes, the user can check information 9053 displayed in a position that can be observed from above mobile information terminal 9102. The user can check the display without taking mobile information terminal 9102 out of the pocket and decide, for example, whether to answer a call.

[0519] FIG. 23C is a perspective view showing a wristwatch-type mobile information terminal 9200. The mobile information terminal 9200 can be used as, for example, a smart watch (registered trademark). The display surface of the display unit 9001 is curved, and a display can be performed along the curved display surface. The mobile information terminal 9200 can also perform hands-free communication by communicating with, for example, a headset capable of wireless communication. The mobile information terminal 9200 can also perform data transmission and reception with another information terminal and charge itself via a connection terminal 9006. Note that charging may be performed by wireless power supply.

[0520] 23D to 23F are perspective views showing a foldable mobile information terminal 9201. FIG. 23D shows the mobile information terminal 9201 in an unfolded state, FIG. 23F shows it in a folded state, and FIG. 23E is a perspective view showing a state in the process of changing from one of FIG. 23D and FIG. 23F to the other. The mobile information terminal 9201 is highly portable when folded, and has a seamless, wide display area when unfolded, providing excellent viewability of the display. The display unit 9001 of the mobile information terminal 9201 is supported by three housings 9000 connected by hinges 9055. For example, the display unit 9001 can be bent with a curvature radius of 0.1 mm or more and 150 mm or less.

[0521] At least a part of the configuration examples exemplified in this embodiment and the corresponding drawings can be combined as appropriate with other configuration examples or drawings.

[0522] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0523] (Embodiment 9) In this embodiment, the relationship between the screen size and pixel density of an electronic device equipped with a display device using an OLED, and techniques applicable to the display device will be described.

[0524] Figure 24 is a diagram showing the relationship between product screen size and pixel density. The horizontal axis is screen size (inches), and the vertical axis is pixel density (ppi). Figure 24 shows the range of typical screen sizes and pixel densities for products such as μOLEDs used in AR or VR products, smartphones, watch-type devices, laptops, tablet devices, in-car displays, monitors, and televisions (TVs). It can be seen that, generally, the smaller the screen size, the higher the resolution.

[0525] In addition, Figure 24 lists the technologies that can be applied to each product, where BP stands for backplane and FP stands for frontplane.

[0526] Regarding the front plane, technologies for achieving full color on OLED can be broadly divided into paint-separating technology using a fine metal mask (FMM+SBS), paint-separating technology using printing methods such as inkjet (printing+SBS), technology that combines white OLED with a color filter (W+CF), and technology that combines blue OLED with quantum dots (B+Qd).

[0527] OLEDs are classified into a tandem structure in which a plurality of light-emitting units are stacked, and a single structure in which no light-emitting units are stacked.

[0528] Backplane manufacturing technologies include LSI technology using Si substrates, LTPS (Low Temperature Poly Silicon) technology, LTPO (Low Temperature Polysilicon and Oxide) technology, and OS (Oxide Semiconductor) technology.

[0529] Here, the technology for creating different OLEDs using photolithography without using a fine metal mask is called MML (Metal Mask Less) technology. Compared to the full-color technology described above, MML technology can achieve a high aperture ratio, high efficiency, high brightness, high display quality, high contrast, and high reliability. MML technology can be applied to display devices with all screen sizes and resolutions shown in Figure 24. It is particularly suitable for use in microdisplays with a screen size of around 1 inch and a resolution of over 1000 ppi.

[0530] Furthermore, the technology that combines fine metal masks and photolithography is called HMML (Hybrid MML).HMML technology can replace the conventional full-color technology using FMM+SBS, and is capable of achieving higher aperture ratios, higher reliability, higher display quality, and higher contrast than this technology.

[0531] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification. [Explanation of symbols]

[0532] 100: display device, 101: substrate, 103: pixel, 105: insulating layer, 110B: light-emitting element, 110G: light-emitting element, 110R: light-emitting element, 110: light-emitting element, 111B: pixel electrode, 111C: connection 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: pixel, 125b: pixel, 125f: insulating film, 125: insulating layer, 126: resin layer, 130: connecting portion, 131: insulating layer, 132: insulating layer, 135B: layer, 135G: layer, 135R: layer, 143: resist mask, 144: sacrificial film, 145: sacrificial layer, 146: sacrificial film, 147: sacrificial layer, 151B: FMM, 151G: FMM, 151R: FMM, 161: conductive layer, 162: conductive layer, 163: resin layer

Claims

1. 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 stacked in this order; the second light-emitting element includes a second pixel electrode, a second light-emitting layer, and the common electrode stacked in this order; a first layer and a second layer in a region between the first light-emitting element and the second light-emitting element; the first layer overlaps the second light-emitting layer and contains the same material as the first light-emitting layer; the second layer overlaps the first light-emitting layer and contains the same material as the second light-emitting layer; an end of the first light-emitting layer and an end of the first layer are provided to face each other in a region between the first light-emitting element and the second light-emitting element; an end of the second light-emitting layer and an end of the second layer are provided to face each other in a region between the first light-emitting element and the second light-emitting element; Display device.

2. a first light-emitting element and a second light-emitting element; the first light-emitting element includes a first pixel electrode, a first light-emitting layer, a first intermediate layer, a third light-emitting layer, and a common electrode stacked in this order; the second light-emitting element includes a second pixel electrode, a second light-emitting layer, a second intermediate layer, a fourth light-emitting layer, and the common electrode stacked in this order; a first layer, a second layer, a third layer, and a fourth layer are disposed between the first light-emitting element and the second light-emitting element; the first layer overlaps 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 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 the first layer and contains the same material as the third light-emitting layer; the fourth layer overlaps the second layer and contains the same material as the fourth light-emitting layer; an end of the first light-emitting layer and an end of the first layer are provided to face each other in a region between the first light-emitting element and the second light-emitting element; an end of the second light-emitting layer and an end of the second layer are provided to face each other in a region between the first light-emitting element and the second light-emitting element; an end of the third light-emitting layer and an end of the third layer are provided to face each other in a region between the first light-emitting element and the second light-emitting element; an end of the fourth light-emitting layer and an end of the fourth layer are provided to face each other in a region between the first light-emitting element and the second light-emitting element; Display device.

3. In claim 2, the first light-emitting layer and the third light-emitting layer contain the same material; the second light-emitting layer and the fourth light-emitting layer contain the same material; Display device.

4. In any one of claims 1 to 3, having a resin layer, the resin layer is located in a region between the first light-emitting element and the second light-emitting element, an end of the first light-emitting layer and an end of the first layer face each other with the resin layer interposed therebetween; an end portion of the second light-emitting layer and an end portion of the second layer face each other with the resin layer interposed therebetween; Display device.

5. In any one of claims 1 to 4, a first insulating layer; the first insulating layer is located in a region between the first light-emitting element and the second light-emitting element, the first insulating layer is in contact with an end portion of the first light-emitting layer, an end portion of the second light-emitting layer, an end portion of the first layer, and an end portion of the second layer; Display device.

6. a first step of forming a first pixel electrode and a second pixel electrode side by side; a second step of forming an island-shaped first light-emitting layer on the first pixel electrode using a first metal mask; a third step of forming an island-shaped second light-emitting layer on the second pixel electrode using a second metal mask so as to overlap an end portion of the first light-emitting layer; a fourth step of separating the first light-emitting layer and the second light-emitting layer by etching in a region between the first pixel electrode and the second pixel electrode; a fifth step of forming a common electrode to cover the first light-emitting layer and the second light-emitting layer; A method for manufacturing a display device.

7. In claim 6, After the fourth step and before the fifth step, a sixth step of forming a resin layer in the slit formed by the etching; A method for manufacturing a display device.

8. In claim 7, The resin layer is made of a photosensitive organic resin. A method for manufacturing a display device.

9. In claim 7 or claim 8, After the fourth step and before the sixth step, a seventh step of forming a first insulating layer in contact with a side surface of the first light-emitting layer and a side surface of the second light-emitting layer exposed by the etching; A method for manufacturing a display device.

10. In claim 9, The first insulating layer is an inorganic insulating film formed by atomic layer deposition. A method for manufacturing a display device.

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