Display device

Abstract

To provide a display device having an imaging function. A display device or an imaging device with a high aperture ratio is provided.SOLUTION: The display device includes a first light-emitting element and a light-receiving element. In the first light-emitting element, a first pixel electrode, a first organic layer, and a common electrode are stacked in this order. In the light-receiving element, the second pixel electrode, the second organic layer, and the common electrode are stacked in this order. The first organic layer includes a first light emitting layer, and the second organic layer includes a photoelectric conversion layer. A first layer and a second layer are provided in a region between the first light-emitting element and the light-receiving element. The first layer overlaps with the second organic layer and contains the same material as the first organic layer. The second layer overlaps with the first organic layer and contains the same material as the second organic layer. In a region between the first light-emitting element and the light-receiving element, an end portion of the first organic layer and an end portion of the first layer are provided to face each other, and an end portion of the second organic layer and an end portion of the second layer are provided to face each other.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] FIELD OF THE INVENTION One aspect of the present invention relates to a display device, an imaging device, and a display device having an imaging function.

[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, display devices have been required to have higher definition in order to display high-resolution images. Furthermore, in information terminal devices such as smartphones, tablet terminals, and notebook PCs (personal computers), display devices are required to have not only high definition but also low power consumption. Furthermore, display devices that not only display images but also have various additional functions, such as a touch panel function or a function for capturing fingerprints for authentication, are in demand.

[0004] As a display device, for example, a light-emitting device having a light-emitting element has been developed. Light-emitting elements (also referred to as EL elements) that utilize the electroluminescence (hereinafter referred to as EL) phenomenon have features such as being easily made thin and lightweight, being capable of responding quickly to input signals, and being able to be driven using a DC constant voltage power supply, and are therefore applied to display devices. For example, Patent Document 1 discloses a flexible light-emitting device that uses an organic EL element. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-197522 Summary of the Invention [Problem to be solved by the invention]

[0006] An object of one embodiment of the present invention is to provide a display device having an imaging function. Another object is to provide an imaging device or a display device having a high-resolution display portion. Another object is to provide a display device or an imaging device with a high aperture ratio. Another object is to provide an imaging device or a display device that can perform imaging with high sensitivity. Another object is to provide a display device that can acquire biometric information such as a fingerprint. Another object is to provide a display device that functions as a touch panel.

[0007] An object of one embodiment of the present invention is to provide a highly reliable display device, imaging device, or electronic device.An object of one embodiment of the present invention is to provide a display device, imaging device, electronic device, or the like having a novel structure.An object of one embodiment of the present invention is to alleviate at least one of the problems of the prior art.

[0008] 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]

[0009] One embodiment of the present invention is a display device including a first light-emitting element and a light-receiving element. The first light-emitting element has a first pixel electrode, a first organic layer, and a common electrode stacked in this order. The light-receiving element has a second pixel electrode, a second organic layer, and a common electrode stacked in this order. The first organic layer includes a first light-emitting layer. The second organic layer includes a photoelectric conversion layer. A first layer and a second layer are provided in a region between the first light-emitting element and the light-receiving element. The first layer overlaps with the second organic layer and contains the same material as the first organic layer. The second layer overlaps with the first organic layer and contains the same material as the second organic layer. In the region between the first light-emitting element and the light-receiving element, an end of the first organic layer faces an end of the first layer. In the region between the first light-emitting element and the light-receiving element, an end of the second organic layer and an end of the second layer are provided to face each other.

[0010] In the above, it is preferable to have a second light-emitting element. The second light-emitting element has a third pixel electrode, a third organic layer, and a common electrode stacked in this order. The third organic layer includes a second light-emitting layer. In addition, a third layer and a fourth layer are provided in a region between the second light-emitting element and the first light-emitting element. The third layer preferably overlaps the third organic layer and contains the same material as the first organic layer. In addition, the fourth layer preferably overlaps the first organic layer and contains the same material as the third organic layer. In addition, in the region between the second light-emitting element and the first light-emitting element, an end of the first organic layer and an end of the third layer are preferably provided opposite each other. In addition, in the region between the second light-emitting element and the first light-emitting element, an end of the third organic layer and an end of the fourth layer are preferably provided opposite each other.

[0011] In any of the above, it is preferable that a resin layer is provided. The resin layer is located in a region between the first light-emitting element and the light-receiving element. It is also preferable that an end of the first organic layer and an end of the first layer face each other with the resin layer interposed therebetween. It is also preferable that an end of the second organic layer and an end of the second layer face each other with the resin layer interposed therebetween.

[0012] In any of the above, it is preferable that a first insulating layer is provided. The first insulating layer is located between the first light-emitting element and the light-receiving element. It is also preferable that the first insulating layer contacts an end of the first organic layer, an end of the second organic layer, an end of the first layer, and an end of the second layer.

[0013] Another embodiment of the present invention is a method for manufacturing a display device, the method 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 organic layer over the first pixel electrode using a first metal mask; a third step of forming an island-shaped second organic layer over the second pixel electrode using a second metal mask; a fourth step of separating the first organic layer and the second organic 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 organic layer and the second organic layer, wherein the first organic layer contains a light-emitting organic compound and the second organic layer contains a photoelectric conversion material.

[0014] 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.

[0015] In the above, it is preferable that the resin layer is made of a photosensitive organic resin.

[0016] 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 organic layer and the second organic layer exposed by etching.

[0017] In the above, the first insulating layer is preferably a metal oxide film formed by atomic layer deposition. [Effects of the Invention]

[0018] According to one embodiment of the present invention, a display device having an imaging function can be provided. Alternatively, an imaging device or display device having a high-definition display portion can be provided. Alternatively, a display device or imaging device with a high aperture ratio can be provided. Alternatively, an imaging device or display device capable of performing high-sensitivity imaging can be provided. Alternatively, a display device capable of acquiring biometric information such as a fingerprint can be provided. Alternatively, a display device functioning as a touch panel can be provided.

[0019] According to one embodiment of the present invention, it is possible to provide a highly reliable display device, an imaging device, or an electronic device. Alternatively, it is possible to provide a display device, an imaging device, an electronic device, or the like having a novel configuration. Alternatively, it is possible to alleviate at least one of the problems of the prior art.

[0020] 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]

[0021] [Figure 1] 1A to 1C are diagrams showing configuration examples of a display device. [Figure 2] 2A and 2B are diagrams showing configuration examples of a display device. [Figure 3] 3A and 3B are diagrams showing configuration examples of a display device. [Figure 4] 4A and 4B are diagrams showing configuration examples of a display device. [Figure 5] 5A and 5B are diagrams showing configuration examples of a display device. [Figure 6] 6A and 6B are diagrams showing configuration examples of a display device. [Figure 7] 7A to 7C are diagrams showing an example of a method for manufacturing a display device. [Figure 8]8A to 8C are diagrams showing an example of a method for manufacturing a display device. [Figure 9] 9A to 9C are diagrams showing an example of a method for manufacturing a display device. [Figure 10] 10A to 10C are diagrams showing an example of a method for manufacturing a display device. [Figure 11] 11A to 11C are diagrams showing an example of a method for manufacturing a display device. [Figure 12] FIG. 12 is a diagram illustrating an example of the configuration of a display device. [Figure 13] Fig. 13A is a diagram showing a configuration example of a display device, and Fig. 13B is a diagram showing a configuration example of a transistor. [Figure 14] Figures 14A, 14B and 14D are cross-sectional views showing examples of display devices, Figures 14C and 14E are diagrams showing example images, and Figures 14F to 14H are top views showing example pixels. [Figure 15] 15A is a cross-sectional view showing an example of the configuration of a display device, and FIGS. 15B to 15D are top views showing examples of pixels. [Figure 16] 16A is a cross-sectional view showing an example of the configuration of a display device, and FIGS. 16B to 16I are top views showing an example of a pixel. [Figure 17] 17A and 17B are diagrams showing configuration examples of a display device. [Figure 18] 18A to 18G are diagrams showing configuration examples of the display device. [Figure 19] Figures 19A to 19F show examples of pixels, and Figures 19G and 19H show examples of circuit diagrams of pixels. [Figure 20] 20A to 20J are diagrams showing configuration examples of the display device. [Figure 21] 21A and 21B are diagrams showing an example of an electronic device. [Figure 22] 22A to 22D are diagrams showing an example of an electronic device. [Figure 23] 23A to 23F are diagrams showing an example of an electronic device. [Figure 24]24A to 24F are diagrams showing an example of an electronic device. DETAILED DESCRIPTION OF THE INVENTION

[0022] 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.

[0023] 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.

[0024] 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.

[0025] In this specification, ordinal numbers such as "first" and "second" are used to avoid confusion of components and do not limit the number.

[0026] In the following, expressions indicating directions such as "up" and "down" will basically be used in accordance with the directions in the drawings. However, for purposes such as facilitating explanation, the directions indicated by "up" or "down" in the specification may not match those in the drawings. For example, when explaining the stacking order (or formation order) of a laminate, etc., even if the surface on which the laminate is provided in the drawing (such as the surface to be formed, the supporting surface, the adhesive surface, or the flat surface) is located above the laminate, the direction toward that surface may be expressed as "down" and the opposite direction as "up."

[0027] 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."

[0028] 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.

[0029] 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.

[0030] 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.

[0031] (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.

[0032] One embodiment of the present invention is a display device including a light-emitting element (also referred to as a light-emitting device) and a light-receiving element (also referred to as a light-receiving device). The light-emitting element has a pair of electrodes and an EL layer therebetween. The light-receiving element has a pair of electrodes and an active layer therebetween. The light-emitting element is preferably an organic EL element (organic electroluminescent element). The light-receiving element is preferably an organic photodiode (organic photoelectric conversion element).

[0033] Furthermore, the display device preferably has two or more light-emitting elements that emit different colors. The light-emitting elements that emit different colors have EL layers containing different materials. 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] One embodiment of the present invention functions as an imaging device because it can capture an image using a plurality of light-receiving elements. In this case, the light-emitting elements can be used as a light source for capturing an image. Another embodiment of the present invention functions as a display device because it can display an image using a plurality of light-emitting elements. Therefore, one embodiment of the present invention can be said to be a display device having an imaging function or an imaging device having a display function.

[0035] For example, in a display device according to one embodiment of the present invention, light-emitting elements are arranged in a matrix in the display portion, and light-receiving elements are also arranged in a matrix in the display portion. Therefore, the display portion has a function of displaying an image and a function as a light-receiving portion. Since images can be captured by the light-receiving elements provided in the display portion, the display device can function as an image sensor or a touch panel. That is, the display portion can capture an image or detect the approach or contact of an object. Furthermore, since the light-emitting elements provided in the display portion can be used as a light source for receiving light, there is no need to provide a light source separately from the display device, and a highly functional display device can be realized without increasing the number of electronic components.

[0036] In one embodiment of the present invention, when light emitted from a light-emitting element included in a display portion is reflected by an object, the light-receiving element can detect the reflected light; therefore, imaging and touch (including non-touch) detection can be performed even in a dark environment.

[0037] Furthermore, the display device of one embodiment of the present invention can capture an image of a fingerprint or palm print when a finger or palm is placed in contact with the display unit. Therefore, an electronic device equipped with the display device of one embodiment of the present invention can perform personal authentication using the captured image of the fingerprint or palm print. This eliminates the need for a separate imaging device for fingerprint or palm print authentication, thereby reducing the number of components in the electronic device. Furthermore, since the light receiving elements are arranged in a matrix on the display unit, fingerprints and palm prints can be captured anywhere on the display unit, resulting in an electronic device with excellent convenience.

[0038] 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.

[0039] 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.

[0040] Furthermore, if a similar leakage current occurs between the light-emitting element and the light-receiving element, the leakage current may become a source of noise when imaging using the light-receiving element, which may result in a decrease in imaging sensitivity (S / N ratio).

[0041] Therefore, in one embodiment of the present invention, an FMM is used to separately fabricate organic films between adjacent light-emitting elements and light-receiving elements, or between two adjacent light-emitting elements, so that their respective organic films partially overlap. Specifically, a layer containing a light-emitting organic compound (also referred to as a light-emitting layer) in a light-emitting element and a layer containing a photoelectric conversion material (also referred to as an active layer or photoelectric conversion layer) in a light-receiving element are separately fabricated using an FMM. In this case, organic films that can be shared between the light-emitting elements and the light-receiving elements may be used as common films between the light-emitting elements and between the light-emitting elements and the light-receiving elements. An organic stacked film, in which a light-emitting layer, an active layer, and other organic films are stacked, is located between adjacent light-emitting elements and light-receiving elements. Subsequently, the organic stacked film is divided by partially etching the organic stacked film using photolithography. This divides the current leakage path between the light-emitting element and the light-receiving element. This reduces noise during imaging using a light-receiving element, enabling high-sensitivity imaging.

[0042] Furthermore, it is possible to separate the current leakage path between two adjacent light-emitting elements, which makes it possible to increase brightness, contrast, power efficiency, or reduce power consumption.

[0043] 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.

[0044] Below, a structural example of a display device according to one embodiment of the present invention and an example of a manufacturing method thereof will be described with reference to the drawings.

[0045] [Configuration example 1] 1A shows a schematic top view of display device 100. Display device 100 has a plurality of red light-emitting elements 110R, green light-emitting elements 110G, blue light-emitting elements 110B, and light-receiving elements 110S. In FIG. 1A, to easily distinguish between the light-emitting elements, the symbols R, G, B, and S are assigned within the light-emitting regions of the light-emitting elements or light-receiving elements.

[0046] The light-emitting elements 110R, 110G, 110B, and the light-receiving elements 110S are arranged in a matrix. Fig. 1A shows a configuration in which two elements are alternately arranged in one direction. The arrangement of the light-emitting elements is not limited to this, and other arrangements such as a stripe arrangement, an S-stripe arrangement, a delta arrangement, a Bayer arrangement, or a zigzag arrangement may also be used. A pentile arrangement, a diamond arrangement, or the like may also be used.

[0047] 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.

[0048] The light receiving element 110S can be, for example, a pn-type or pin-type photodiode. The light receiving element 110S functions as a photoelectric conversion element that detects light incident on the light receiving element 110S and generates an electric charge. The amount of electric charge generated by the photoelectric conversion element is determined according to the amount of incident light. In particular, it is preferable to use an organic photodiode having a layer containing an organic compound as the light receiving element 110S. 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 devices.

[0049] 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.

[0050] 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.

[0051] 1B and 1C are schematic cross-sectional views corresponding to dashed dotted lines A1-A2 and C1-C2 in Fig. 1A, respectively. Fig. 1B shows a schematic cross-sectional view of light-emitting element 110G, light-emitting element 110R, and light-receiving element 110S, and Fig. 1C shows a schematic cross-sectional view of connection electrode 111C.

[0052] FIG. 1B shows cross sections of the light-emitting element 110R, the light-emitting element 110G, and the light-receiving element 110S. The light-emitting element 110R includes 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. The light-emitting element 110G includes 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. The light-receiving element 110S includes a pixel electrode 111S, an organic layer 115, an organic layer 115, 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 the light-emitting element 110R, the light-emitting element 110G, the light-receiving element 110S, and the light-emitting element 110B (not shown). The organic layer 114 can also be referred to as a common layer.

[0053] Organic layer 112R of light-emitting element 110R contains a light-emitting organic compound that emits at least red light. Organic layer 112G of light-emitting element 110G contains a light-emitting organic compound that emits at least green light. Organic layer 112B (not shown) of light-emitting element 110B contains a light-emitting organic compound that emits at least blue light. Organic layer 112R, organic layer 112G, and organic layer 112B can each be referred to as a light-emitting layer.

[0054] The organic layer 155 of the light receiving element 110S contains a photoelectric conversion material that is sensitive to the wavelength range of visible light or infrared light. The wavelength range to which the photoelectric conversion material of the organic layer 155 is sensitive preferably includes one or more of the wavelength range of light emitted by the light emitting element 110R, the wavelength range of light emitted by the light emitting element 110G, and the wavelength range of light emitted by the light emitting element 110B. Alternatively, a photoelectric conversion material that is sensitive to infrared light with a longer wavelength than the wavelength range of light emitted by the light emitting element 110R may be used. The organic layer 155 may also be called an active layer or a photoelectric conversion layer.

[0055] 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.

[0056] In each light-emitting element, the laminated film located between the pixel electrode and the common electrode 113 can be called an EL layer. In addition, in the light-receiving element 110S, the laminated film located between the pixel electrode 111S and the common electrode 113 can be called a PD layer.

[0057] In each light-emitting element or light-receiving element 110S, organic layer 115 is a layer located between organic layer 112 or organic layer 155 and pixel electrode 111. Organic layer 116 is a layer located between organic layer 112 or organic layer 155 and organic layer 114. Organic layer 114 is a layer located between organic layer 116 and common electrode 113.

[0058] 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.

[0059] It should be noted that the term "organic layer" used for layers located between a pair of electrodes of the light-emitting element or light-receiving element 110S, such as organic layer 112, organic layer 114, organic layer 115, organic layer 116, and organic layer 155, is intended to refer to layers that constitute an organic EL element or an organic photoelectric conversion element, and do 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.

[0060] The pixel electrode 111R, pixel electrode 111G, and pixel electrode 111B (not shown) 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 and light-receiving element 110S. A conductive film that is translucent to visible light is used for either one of the pixel electrodes 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.

[0061] A protective layer 121 is provided on the common electrode 113 to cover the light emitting element 110R, the light emitting element 110G, the light receiving element 110S, and the light emitting element 110B (not shown). The protective layer 121 has a function of preventing impurities such as water from diffusing from above into each light emitting element.

[0062] Slits 120 are provided between adjacent light-emitting elements and light-receiving elements 110S and between two adjacent light-emitting elements. Slits 120 correspond to etched portions of organic layer 112 or organic layer 155, organic layer 115, and organic layer 116 located between adjacent light-emitting elements and light-receiving elements 110S or between two adjacent light-emitting elements.

[0063] An insulating layer 125 and a resin layer 126 are provided in the slit 120. 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 has the function of filling the recesses located in the slit 120 and flattening the upper surface. By flattening the recesses of the slit 120 with the resin layer 126, it is possible to improve the coverage of the organic layer 114, the common electrode 113, and the protective layer 121.

[0064] Furthermore, the slits 120 can be formed simultaneously with the formation of openings for external connection terminals such as the connection electrode 111C, and therefore these can be formed without increasing the number of processes. Furthermore, the slits 120 have the insulating layer 125 and the resin layer 126, which has the effect of preventing short circuits between the pixel electrode 111 and the common electrode 113. Furthermore, the resin layer 126 has the effect of improving the adhesion of the organic layer 114. That is, by providing the resin layer 126, the adhesion of the organic layer 114 is improved, and therefore peeling of the organic layer 114 can be suppressed.

[0065] Since the insulating layer 125 is provided in contact with the side surface of an organic layer (e.g., organic layer 115), a structure can be achieved in which the organic layer does not come into contact with the resin layer 126. 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, active layer, hole blocking layer, electron transport layer, and electron injection layer.

[0066] 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.

[0067] 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.

[0068] 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.

[0069] An insulating layer containing an organic material can be suitably used as the resin layer 126. For example, acrylic resin, polyimide resin, epoxy resin, imide resin, polyamide resin, polyimideamide resin, silicone resin, siloxane resin, benzocyclobutene resin, phenol resin, precursors of these resins, etc. can be used as the resin layer 126. Alternatively, organic materials such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinylpyrrolidone, polyethylene glycol, polyglycerin, pullulan, water-soluble cellulose, or alcohol-soluble polyamide resin can be used as the resin layer 126.

[0070] Furthermore, a photosensitive resin can be used as the resin layer 126. A photoresist can be used as the photosensitive resin. The photosensitive resin can be a positive type material or a negative type material.

[0071] Furthermore, by using a colored material (for example, a material containing a black pigment) for the resin layer 126, the layer may be provided with the function of blocking stray light from adjacent pixels and suppressing color mixing.

[0072] 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.

[0073] The upper surface of the resin layer 126 is preferably as flat as possible, but the surface 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.

[0074] 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.

[0075] 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.

[0076] 1C shows a connection section 130 where the connection electrode 111C and the common electrode 113 are electrically connected. In the connection section 130, the common electrode 113 is provided on the connection electrode 111C via an organic layer 114. 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.

[0077] 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.

[0078] Next, a preferred configuration of the slit 120 and its vicinity will be described in detail. Figure 2A 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.

[0079] As shown in Fig. 2A, 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, the 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. Although the pixel electrode 111R, etc. has a single-layer structure in this example, multiple layers may be stacked.

[0080] 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.

[0081] 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.

[0082] 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.

[0083] An end (side surface) of organic layer 112R and an end of layer 135R are provided opposite each other with slit 120 interposed therebetween. Similarly, an end of organic layer 112G and an end of layer 135G are provided opposite each other with slit 120 interposed therebetween.

[0084] 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.

[0085] 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.

[0086] 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.

[0087] 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.

[0088] 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.

[0089] 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 or the boundary between layer 135G and organic layer 112R by cross-sectional observation.

[0090] 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 obtained 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., 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 be possible to estimate the compounds contained in layers 135R and 135G.

[0091] 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.

[0092] FIG. 2B shows a schematic cross-sectional view of a part of the light-emitting element 110G, a part of the light-receiving element 110S, and the slit 120 located between them.

[0093] Layer 135S is provided on organic layer 112G, closer to light emitting element 110G than slit 120. Layer 135S can also be described as a fragment of a part of the film that will become organic layer 155, which is separated by slit 120 and remains on the light emitting element 110G side. Layer 135S and organic layer 155 are provided opposite each other with slit 120 sandwiched between them.

[0094] Furthermore, layer 135G is provided on the light receiving element 110S side of slit 120 so as to be sandwiched between organic layer 115 and organic layer 155. Layer 135G and organic layer 112G are provided opposite each other with slit 120 interposed therebetween.

[0095] In the enlarged views shown in Figures 2A and 2B, the area between light-emitting element 110R and light-emitting element 110G and the area between light-emitting element 110G and light-receiving element 110S have been described, but similar configurations also exist between light-emitting element 110R and light-emitting element 110B, between light-emitting element 110G and light-emitting element 110B, between light-emitting element 110R and light-receiving element 110S, and between light-emitting element 110B and light-receiving element 110S.

[0096] 3A and 3B are cross-sectional schematic diagrams each showing a case where insulating layer 125 is not provided. In Fig. 3A, resin layer 126 is provided 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. In Fig. 3B, resin layer 126 is provided in contact with the side surfaces of organic layer 155 and layer 135S.

[0097] At this time, the EL layer or PD layer may be partially dissolved by the solvent used in forming the film that will become the resin layer 126. Therefore, if 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 and the PD layer may be used.

[0098] As described above, the display device of one embodiment of the present invention can have a structure in which an insulator covering an edge of a pixel electrode is not provided. In other words, the display device of one embodiment of the present invention has a structure in which an insulator is not provided between the pixel electrode and the EL layer. With this structure, light emitted from the EL layer can be efficiently extracted, thereby significantly reducing viewing angle dependence. For example, in the display device of one embodiment of the present invention, the viewing angle (the maximum angle at which a certain contrast ratio is maintained when the screen is viewed from an oblique direction) can be set to a range of 100° to less than 180°, preferably 150° to 170°. Note that the above viewing angle can be applied to both the vertical and horizontal directions. The display device of one embodiment of the present invention can have improved viewing angle characteristics and thus can enhance image visibility.

[0099] [Variations] Figures 4A and 4B are modifications of Figures 2A and 2B, respectively. Figures 4A and 4B show an example in which an insulating layer 131 is provided to cover the edge of the pixel electrode.

[0100] 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.

[0101] 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.

[0102] 4A and 4B, 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.

[0103] The slit 120 is provided in a region overlapping with the insulating layer 131. The layer 135R, the layer 135G, and the layer 135S are also provided in a region overlapping with the insulating layer 131.

[0104] 5A and 5B show an example in which an insulating layer 132 is provided on an insulating layer 131. In FIG.

[0105] 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.

[0106] 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.

[0107] 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.

[0108] 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.

[0109] The insulating layer 132 may also be a stack of films containing the above inorganic insulating materials. For example, it 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 them 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.

[0110] 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.

[0111] 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.

[0112] [Configuration example 2] A more specific configuration example will be described below.

[0113] Fig. 6A is a schematic cross-sectional view of a display device exemplified below. Fig. 6A shows a cross section of a region including light-emitting element 110R, light-emitting element 110G, light-emitting element 110B, light-receiving element 110S, and connection portion 130. Fig. 6B is an enlarged schematic cross-sectional view of slit 120 located between light-emitting element 110R and light-emitting element 110G and its vicinity.

[0114] The 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. In Fig. 6A, a layer 135B, which is a part (a scrap) of the organic layer 112B separated by a slit 120, is provided near the light-emitting element 110R and near the light-receiving element 110S.

[0115] Below the pixel electrode 111, a conductive layer 161, a conductive layer 162, and a resin layer 163 are provided.

[0116] 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.

[0117] The conductive layer 161 has a recess formed in 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 the surface may also have a gently curved shape. While FIG. 6A and other figures show an example in which the upper surface of the resin layer 163 has a corrugated 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.

[0118] 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.

[0119] 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 111, 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 an 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 also be a light-emitting region. Therefore, the aperture ratio can be increased.

[0120] Similarly, when the light receiving element 110S is used as a photoelectric conversion element that receives light from above, a reflective film can be used for the conductive layer 162, and a light-transmitting film can be used for the pixel electrode 111. Furthermore, the contact portion can also function as a light receiving region, thereby expanding the light receiving area and improving the light receiving sensitivity.

[0121] The thickness of each pixel electrode 111 may be different. In this case, the pixel electrode 111 can be used as an optical adjustment layer for the microcavity. When a microcavity is used, a film having transparency and reflectivity is used as the common electrode.

[0122] 6A and 6B show an example in which the shape of the resin layer 126 is different from that described above.

[0123] As shown in FIG. 6B , 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.

[0124] 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.

[0125] As shown in FIGS. 6A and 6B, the layers 135R, 135G, 135B, and 135S 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.

[0126] [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. 6A will be used as an example. FIGS. 7A to 10C 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. 7A and other drawings, cross-sectional schematic views of the connection portion 130 and its vicinity are also shown on the right side.

[0127] 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.

[0128] 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.

[0129] 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.

[0130] 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.

[0131] 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.

[0132] For etching the thin film, dry etching, wet etching, sandblasting, or the like can be used.

[0133] [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.

[0134] 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.

[0135] 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.

[0136] The insulating layer 105 can be made of an inorganic insulating material or an organic insulating material.

[0137] [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.

[0138] Subsequently, a resin layer 163 is formed in the recesses of the conductive film.

[0139] 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.

[0140] Furthermore, when a non-photosensitive resin is used as the resin layer 163, after forming the resin film, the resin layer 163 can be formed by etching the upper part of the resin film by ashing or the like until the surface of the conductive film that will become the conductive layer 161 is exposed so as to optimize the thickness.

[0141] 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.

[0142] Although the conductive layers 161 and 162 are formed in the same process using the same photomask here, the conductive layers 161 and 162 may be formed separately using different photomasks. In this case, it is preferable to process the conductive layers 161 and 162 so that the conductive layer 161 is included inside the contour of the conductive layer 162 in a plan view.

[0143] Subsequently, 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. 7A). 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. 7A, because the conductive layers 161 and 162 are not exposed to the etching atmosphere during the formation of the pixel electrode 111, etc.

[0144] [Formation of organic layer 115] Subsequently, the organic layer 115 is formed on the pixel electrode 111 (FIG. 7B). The organic layer 115 is preferably formed without using an FMM.

[0145] 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.

[0146] The organic layer 115 can be preferably formed by vacuum deposition. However, the method is not limited to this, and it can also be formed by sputtering, inkjet printing, etc. Furthermore, the above-mentioned film formation methods can be used as appropriate.

[0147] [Formation of Organic Layer 112R, Organic Layer 112G, Organic Layer 112B, and Organic Layer 155] 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.

[0148] 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.

[0149] 7C 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.

[0150] 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 7C, 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.

[0151] Subsequently, an organic layer 112G is formed on the pixel electrode 111G using an FMM 151G (FIG. 8A).

[0152] Similar to the organic layer 112R, the organic layer 112G is formed with 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 is formed.

[0153] Next, an organic layer 112B is formed on the pixel electrode 111B using an FMM 151B (not shown), and then an organic layer 155 is formed on the pixel electrode 111S using an FMM 151S.

[0154] Similar to organic layer 112R and organic layer 112G, organic layer 112B and organic layer 155 also have patterns that extend outward from pixel electrode 111B or pixel electrode 111S. As a result, as shown in Fig. 8B, a region GB where organic layer 112B is stacked on organic layer 112G, a region BS where organic layer 155 is stacked on organic layer 112B, and a region RS where organic layer 155 is stacked on organic layer 112R are formed. Although not shown here, a region where organic layer 155 is stacked on organic layer 112G, a region where organic layer 112B is stacked on organic layer 112R, and the like are also formed.

[0155] Here, it is preferable that organic layer 112R, organic layer 112G, organic layer 112B, and organic layer 155 are not formed on connection electrode 111C.

[0156] Here, organic layer 112R, organic layer 112G, organic layer 112B, and organic layer 155 are formed in this order, but the order of formation is not limited to this.

[0157] [Formation of organic layer 116] Subsequently, the organic layer 116 is formed to cover the organic layer 112R, the organic layer 112G, the organic layer 112B, and the organic layer 155 (FIG. 8C). The organic layer 116 can be formed by the same method as the organic layer 115.

[0158] [Formation of Sacrificial Film 144] Subsequently, a sacrificial film 144 is formed covering the organic layer 116 .

[0159] For the sacrificial film 144, a film that is highly resistant to the etching process of the organic layers 115, 112, 155, 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, 155, and 116.

[0160] 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.

[0161] 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.

[0162] 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.

[0163] 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.

[0164] 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.

[0165] 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.

[0166] 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.

[0167] 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.

[0168] 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.

[0169] [Formation of Sacrificial Film 146] Subsequently, a sacrificial film 146 is formed on the sacrificial film 144 .

[0170] 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.

[0171] 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.

[0172] 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.

[0173] 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.

[0174] 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.

[0175] 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 155, 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, the organic layer 155, or 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 155, the organic layer 116, and the like. Furthermore, the sacrificial layer can be removed simultaneously when etching the organic layer 115, the organic layer 112, the organic layer 155, the organic layer 116, and the like using the sacrificial layer as a mask later, thereby simplifying the process.

[0176] [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, the pixel electrode 111B, the pixel electrode 111S, and the connection electrode 111C (FIG. 9A).

[0177] 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.

[0178] Here, when the resist mask 143 is formed on the sacrificial film 144 without the sacrificial film 146, if defects such as pinholes exist in the sacrificial film 144, the organic layer 115, the organic layer 112, the organic layer 155, 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.

[0179] In addition, when a material that does not dissolve organic layer 115, organic layer 112, organic layer 155, and organic layer 116 is used as a solvent for the resist material, it may be possible to form resist mask 143 directly on sacrificial film 144 without using sacrificial film 146.

[0180] [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 .

[0181] 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, shrinkage of the pattern of the sacrificial layer 147 can be suppressed.

[0182] [Removal of resist mask 143] Subsequently, the resist mask 143 is removed.

[0183] 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.

[0184] At this time, the removal of the resist mask 143 is performed in a state in which the organic layer 116 is covered with the sacrificial film 144, and therefore the influence on the organic layer 115, the organic layer 112, the organic layer 155, and the organic layer 116 is suppressed. In particular, if the organic layer 115, the organic layer 112, the organic layer 155, 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.

[0185] [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. 9B).

[0186] 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.

[0187] [Etching of organic layer 116, organic layer 112, organic layer 155, and organic layer 115] Subsequently, organic layer 116, organic layer 112, organic layer 155, and a portion of organic layer 115 that is 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.

[0188] At this time, organic layer 112R, organic layer 112G, organic layer 112B, and a portion of organic layer 155 are separated by etching, thereby forming layer 135R, which is a piece of organic layer 112R, layer 135G, which is a piece of organic layer 112G, layer 135B, which is a piece of organic layer 112B, and layer 135S, which is a piece of organic layer 155.

[0189] In particular, dry etching using an etching gas that does not contain oxygen as a main component is preferably used for etching organic layer 116, organic layer 112, organic layer 155, and organic layer 115. This suppresses deterioration of organic layer 116, organic layer 112, organic layer 155, and organic layer 115, thereby achieving a highly reliable display device. Examples of etching gases that do not contain oxygen as a main component include noble gases such as CF4, C4F8, SF6, CHF3, Cl2, H2O, BCl3, H2, and 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.

[0190] The etching of organic layer 116, organic layer 112, organic layer 155, and organic layer 115 is not limited to the above, and may be dry etching using other gases or wet etching.

[0191] Furthermore, when dry etching is used to etch the organic layers 116, 112, 155, and 115 using oxygen gas or a mixed gas containing oxygen gas as an etching gas, the etching rate can be increased. 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, a mixed gas obtained by adding oxygen gas to the above-mentioned etching gas that does not contain oxygen as a main component can be used as the etching gas.

[0192] When the organic layer 116, the organic layer 112, the organic layer 155, 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.

[0193] The sacrificial layer 147 may be etched simultaneously with etching the organic layer 116, the organic layer 112, the organic layer 155, or the organic layer 115. Etching the organic layer 116, the organic layer 112, the organic layer 155, or 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.

[0194] [Removal of Sacrificial Layer] Next, sacrificial layer 147 is removed to expose the upper surface of sacrificial layer 145 (FIG. 9C). At this time, it is preferable to leave sacrificial layer 145. However, sacrificial layer 147 does not necessarily have to be removed at this point.

[0195] [Formation of insulating film 125f] Subsequently, an insulating film 125f is formed to cover the sacrificial layer 145 and the slits 120.

[0196] 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.

[0197] It is preferable that the insulating film 125f is the same film as the sacrificial layer 145, because they can be etched simultaneously in a later step. For example, it is preferable that the insulating film 125f and the sacrificial layer 145 are made of an inorganic insulating material such as aluminum oxide, hafnium oxide, or silicon oxide formed by the ALD method.

[0198] 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.

[0199] [Formation of Resin Layer 126] Subsequently, a resin layer 126 is formed in the region overlapping with the slit 120 (FIG. 10A). The resin layer 126 can be formed by the same method as the resin layer 163.

[0200] 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.

[0201] [Etching of insulating film 125f and sacrificial layer 145] Next, 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. As a result, the insulating layer 125 and the sacrificial layer 145 are formed in the region covered by the resin layer 126 (FIG. 10B).

[0202] 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.

[0203] 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.

[0204] 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, the organic layer 155, the organic layer 116, etc., 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.

[0205] [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.

[0206] 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.

[0207] [Formation of Common Electrode 113] Subsequently, the common electrode 113 is formed to cover the organic layer 114 .

[0208] 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.

[0209] 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.

[0210] 10C shows an example in which an organic layer 114 is sandwiched between a connection electrode 111C and a common electrode 113 as the connection portion 130. 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.

[0211] [Formation of protective layer] Next, a protective layer 121 is formed on the common electrode 113 (FIG. 10C). 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.

[0212] In this manner, the display device shown in FIG. 6A can be manufactured.

[0213] 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.

[0214] FIG. 11A 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.

[0215] 11A, after forming a resin layer 126 that is wider than the slit 120, the upper part of the resin layer 126 is etched by ashing or the like, thereby forming the resin layer 126 only inside the slit 120. At this time, 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 between the portion overlapping with the slit 120 and both ends thereof, thereby improving the step coverage of the organic layer 114, etc.

[0216] Subsequently, the insulating film 125f and the sacrificial layer 145 are etched in the same manner as above (FIG. 11B). 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 pieces.

[0217] 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. 11C.

[0218] 11C 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.

[0219] This completes the description of the example of the method for manufacturing the display device.

[0220] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0221] (Embodiment 2) In this embodiment, a structural example of a display device according to one embodiment of the present invention will be described. Here, a display device capable of displaying an image will be described, but the display device can also be used by using a light-emitting element as a light source.

[0222] 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, and large game machines such as pachinko machines, as well as in the 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 reproduction devices.

[0223] [Display device 400] FIG. 12 shows a perspective view of display device 400, and FIG. 13A shows a cross-sectional view of display device 400.

[0224] The display device 400 has a configuration in which a substrate 452 and a substrate 451 are bonded together. In Fig. 12, the substrate 452 is clearly indicated by a dashed line.

[0225] The display device 400 includes a display portion 462, a circuit 464, wiring 465, etc. Fig. 12 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.

[0226] The circuit 464 can be, for example, a scanning line driver circuit.

[0227] 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.

[0228] 12 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.

[0229] 13A 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 connection portion of display device 400. Fig. 13A shows an example of a cross section of display unit 462, particularly a region including light-emitting element 430b that emits green light (G) and light-receiving element 440 that receives reflected light (L).

[0230] The display device 400 shown in FIG. 13A includes a transistor 252, a transistor 260, a transistor 258, a light-emitting element 430b, a light-receiving element 440, and the like between a substrate 451 and a substrate 452.

[0231] The light emitting element 430b and the light receiving element 440 may be any of the light emitting elements or light receiving elements exemplified above.

[0232] Here, when a pixel of a display device has three types of subpixels having light-emitting elements that emit different colors, the three subpixels may include subpixels of three colors: red (R), green (G), and blue (B), or subpixels of three colors: yellow (Y), cyan (C), and magenta (M). When a pixel of a display device has four subpixels, the four subpixels may include subpixels of four colors: R, G, B, and white (W), or subpixels of four colors: R, G, B, and Y. Alternatively, the subpixels may include light-emitting elements that emit infrared light.

[0233] Furthermore, the light receiving element 440 may be a photoelectric conversion element sensitive to light in the red, green, or blue wavelength range, or a photoelectric conversion element sensitive to light in the infrared wavelength range.

[0234] The substrate 452 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 receiving element 440, respectively, and a solid sealing structure is applied to the display device 400. The substrate 452 is provided with a light-shielding layer 417.

[0235] The light-emitting element 430b and the light-receiving element 440 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.

[0236] A conductive layer 411a included in the light-emitting element 430b is connected to a conductive layer 272b included in the transistor 260 through an opening provided in the insulating layer 294. The transistor 260 has a function of controlling driving of the light-emitting element. On the other hand, the conductive layer 411a included in the light-receiving element 440 is electrically connected to a conductive layer 272b included in the transistor 258. The transistor 258 has a function of controlling the timing of exposure using the light-receiving element 440, for example.

[0237] An EL layer 412G or a PD layer 412S is provided to cover the pixel electrode. An insulating layer 421 is provided in contact with the side surfaces of the EL layer 412G and the PD layer 412S, and a resin layer 422 is provided to fill the recesses in the insulating layer 421. An organic layer 414, a common electrode 413, and a protective layer 416 are provided to cover the EL layer 412G and the PD layer 412S. By providing the protective layer 416 to cover the light-emitting element, it is possible to prevent impurities such as water from entering the light-emitting element and improve the reliability of the light-emitting element.

[0238] Furthermore, a layer 415G and a layer 415S are provided in contact with the insulating layer 421. The layer 415G includes the same material as the EL layer 412G, and the layer 415S includes the same material as the PD layer 412S.

[0239] Light G emitted by light emitting element 430b is emitted toward substrate 452. Light receiving element 440 receives light L incident through substrate 452 and converts it into an electrical signal. Substrate 452 is preferably made of a material that is highly transparent to visible light.

[0240] The transistor 252, the transistor 260, and the transistor 258 are all formed over a substrate 451. These transistors can be manufactured using the same material and the same process.

[0241] Note that the transistor 252, the transistor 260, and the transistor 258 may be fabricated to have different structures. For example, transistors may be fabricated with or without a back gate, or transistors may be fabricated with different materials and / or thicknesses of semiconductors, gate electrodes, gate insulating layers, source electrodes, and drain electrodes.

[0242] The substrate 451 and the insulating layer 262 are bonded together by an adhesive layer 455 .

[0243] In a method for manufacturing the display device 400, first, a manufacturing substrate provided with the insulating layer 262, the transistors, the light-emitting elements, the light-receiving elements, and the like is bonded to a substrate 452 provided with a light-shielding layer 417 with an adhesive layer 442. Then, the manufacturing substrate is peeled off, and a substrate 451 is attached to the exposed surface, so that the components formed on the manufacturing substrate are transferred to the substrate 451. The substrate 451 and the substrate 452 each preferably have flexibility. This can increase the flexibility of the display device 400.

[0244] A connection portion 254 is provided in an area of ​​the substrate 451 where the substrate 452 does not overlap. In the connection portion 254, a wiring 465 is electrically connected to the FPC 472 via a conductive layer 466 and a connection layer 292. The conductive layer 466 can be obtained by processing the same conductive film as the pixel electrode. This allows the connection portion 254 and the FPC 472 to be electrically connected via the connection layer 292.

[0245] The transistor 252, the transistor 260, and the transistor 258 each include a conductive layer 271 functioning as a gate, an insulating layer 261 functioning as a gate insulating layer, a semiconductor layer 281 including a channel formation region 281i and a pair of low-resistance regions 281n, a conductive layer 272a connected to one of the pair of low-resistance regions 281n, a conductive layer 272b connected to the other of the pair of low-resistance regions 281n, an insulating layer 275 functioning as a gate insulating layer, a conductive layer 273 functioning as a gate, and an insulating layer 265 covering the conductive layer 273. The insulating layer 261 is located between the conductive layer 271 and the channel formation region 281i. The insulating layer 275 is located between the conductive layer 273 and the channel formation region 281i.

[0246] The conductive layer 272a and the conductive layer 272b are each connected to the low-resistance region 281n through an opening provided in the insulating layer 265. One of the conductive layer 272a and the conductive layer 272b functions as a source, and the other functions as a drain.

[0247] 13A shows an example in which the insulating layer 275 covers the top surface and side surfaces of the semiconductor layer. The conductive layer 272a and the conductive layer 272b are connected to the low-resistance region 281n through openings provided in the insulating layer 275 and the insulating layer 265, respectively.

[0248] 13B, the insulating layer 275 overlaps with the channel formation region 281i of the semiconductor layer 281 but does not overlap with the low-resistance region 281n. For example, the structure shown in FIG. 13B can be manufactured by processing the insulating layer 275 using the conductive layer 273 as a mask. In FIG. 13B, the insulating layer 265 is provided to cover the insulating layer 275 and the conductive layer 273, and the conductive layer 272a and the conductive layer 272b are connected to the low-resistance region 281n through openings in the insulating layer 265. Furthermore, an insulating layer 268 may be provided to cover the transistor.

[0249] 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.

[0250] The transistors 252, 260, and 258 each 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 the other.

[0251] 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.

[0252] 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).

[0253] 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.

[0254] 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.

[0255] 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.

[0256] For example, when describing a composition in which the atomic ratio of metal elements is In:Ga:Zn=4:2:3 or thereabout, this includes a case in which, when In is taken as 4, Ga is 1 to 3 and Zn is 2 to 4. Furthermore, when describing a composition in which the atomic ratio of metal elements is In:Ga:Zn=5:1:6 or thereabout, this includes a case in which, when In is taken as 5, Ga is more than 0.1 and 2 or less and Zn is 5 to 7 or less. Furthermore, when describing a composition in which the atomic ratio of metal elements is In:Ga:Zn=1:1:1 or thereabout, this includes a case in which, when In is taken as 1, Ga is more than 0.1 and 2 or less and Zn is more than 0.1 and 2 or less.

[0257] 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.

[0258] 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).

[0259] In particular, low-temperature polysilicon has relatively high mobility and can be formed over a glass substrate, and therefore can be suitably used in display devices. For example, a transistor using low-temperature polysilicon for a semiconductor layer can be used as the transistor 252 in the driver circuit, and a transistor using an oxide semiconductor for a semiconductor layer can be used as the transistor 260 and the transistor 258 provided in the pixel.

[0260] 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.

[0261] 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).

[0262] The display device shown in FIG. 13A includes an OS transistor and a common layer between light-emitting elements is separated. This configuration can significantly reduce leakage current that may flow through the transistor and leakage current that may flow between adjacent light-emitting elements (also referred to as lateral leakage current or side leakage current). Furthermore, when an image is displayed on the display device, the viewer can observe one or more of image clarity, image sharpness, high saturation, and a high contrast ratio. By significantly reducing leakage current that may flow through the transistor and lateral leakage current between light-emitting elements, a display with extremely reduced light leakage (so-called floating black) that may occur during black display (also referred to as true black display) can be achieved.

[0263] In particular, among light-emitting devices with an MML structure, by applying a color-coded structure (SBS structure), the layers provided between the light-emitting elements (for example, organic layers used in common between the light-emitting elements, also called common layers) are separated, resulting in a display with no side leakage or extremely little side leakage.

[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 261, 262, 265, 268, and 275. 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 294, 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 452 facing substrate 451. In addition, various optical members can be arranged on the outside of substrate 452. 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 452.

[0270] 13A shows a connection portion 278. The common electrode 413 and a wiring are electrically connected at the connection portion 278. FIG. 13A shows an example in which the same layered structure as that of the pixel electrode is applied to the wiring.

[0271] The substrate 451 and the substrate 452 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 451 and the substrate 452 can increase the flexibility of the display device. Alternatively, a polarizing plate may be used for the substrate 451 or the substrate 452.

[0272] Substrate 451 and substrate 452 can be made of polyester resin such as polyethylene terephthalate (PET) or 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 451 and 452 may be made of glass having a thickness sufficient to provide flexibility.

[0273] 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).

[0274] 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.

[0275] 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.

[0276] 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.

[0277] 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.

[0278] The connection layer 292 may be made of an anisotropic conductive film (ACF), an anisotropic conductive paste (ACP), or the like.

[0279] 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.

[0280] 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.

[0281] 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.

[0282] 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.

[0283] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0284] (Embodiment 3) In this embodiment, a display device according to one embodiment of the present invention will be described.

[0285] A display device of one embodiment of the present invention includes a light-receiving element (also referred to as a light-receiving device) and a light-emitting element (also referred to as a light-emitting device). Alternatively, the display device of one embodiment of the present invention may include a light-receiving and light-emitting element (also referred to as a light-emitting and receiving device) and a light-emitting element.

[0286] First, a display device having a light receiving element and a light emitting element will be described.

[0287] A display device of one embodiment of the present invention includes a light-receiving element and a light-emitting element in a light-receiving and light-emitting portion. In the display device of one embodiment of the present invention, the light-emitting and receiving portion includes light-emitting elements arranged in a matrix, and an image can be displayed in the light-receiving and light-emitting portion. The light-receiving and light-emitting portion also includes light-receiving elements arranged in a matrix, and the light-receiving and light-emitting portion has one or both of an imaging function and a sensing function. The light-receiving and light-emitting portion can be used as an image sensor, a touch sensor, or the like. That is, by detecting light in the light-receiving and light-emitting portion, an image can be captured and a touch operation of an object (such as a finger or a pen) can be detected. Furthermore, in the display device of one embodiment of the present invention, the light-emitting element can be used as a light source for a sensor. Therefore, a light-receiving portion and a light source do not need to be provided separately from the display device, and the number of components in an electronic device can be reduced.

[0288] In the display device of one embodiment of the present invention, when light emitted by a light-emitting element included in the light-emitting and receiving portion is reflected (or scattered) by an object, the light-receiving element can detect the reflected light (or scattered light); therefore, imaging, detection of touch operations, and the like are possible even in dark places.

[0289] The light-emitting element included in the display device of one embodiment of the present invention functions as a display element (also referred to as a display device).

[0290] As the light-emitting element, it is preferable to use an EL element (also called an EL device) such as an OLED or QLED. Examples of light-emitting substances contained in the EL element include a substance that emits fluorescence (a fluorescent material), a substance that emits phosphorescence (a phosphorescent material), and a substance that exhibits thermally activated delayed fluorescence (a thermally activated delayed fluorescence (TADF) material). Also, an LED such as a micro LED can be used as the light-emitting element. As the light-emitting substance contained in the EL element, not only organic compounds but also inorganic compounds (such as quantum dot materials) can be used.

[0291] A display device according to one embodiment of the present invention has a function of detecting light using a light-receiving element.

[0292] When the light receiving element is used as an image sensor, the display device can capture an image using the light receiving element, for example, the display device can be used as a scanner.

[0293] An electronic device to which the display device of one embodiment of the present invention is applied can acquire data related to biometric information such as a fingerprint or palm print by using a function as an image sensor. That is, a biometric authentication sensor can be built into the display device. The built-in biometric authentication sensor in the display device reduces the number of components in the electronic device compared to a case in which a biometric authentication sensor is provided separately from the display device, and the electronic device can be made smaller and lighter.

[0294] Furthermore, when the light receiving element is used as a touch sensor, the display device can detect a touch operation of an object using the light receiving element.

[0295] The light receiving element can be, for example, a pn-type or pin-type photodiode. The light receiving element functions as a photoelectric conversion element (also called a photoelectric conversion device) that detects light incident on the light receiving element and generates electric charge. The amount of electric charge generated by the light receiving element is determined based on the amount of light incident on the light receiving element.

[0296] In particular, it is preferable to use an organic photodiode having a layer containing an organic compound as the light-receiving element. 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 devices.

[0297] In one embodiment of the present invention, an organic EL element (also referred to as an organic EL device) is used as a light-emitting element, and an organic photodiode is used as a light-receiving element. The organic EL element 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 element.

[0298] If all the layers constituting the organic EL element and the organic photodiode were to be fabricated separately, the number of film formation processes would be enormous. However, since the organic photodiode has many layers that can be configured in common with the organic EL element, the layers that can be configured in common can be formed in one go, thereby suppressing the increase in film formation processes.

[0299] For example, one of the pair of electrodes (common electrode) can be a layer common to the light-receiving element and the light-emitting element. Furthermore, for example, at least one of the hole injection layer, the hole transport layer, the electron transport layer, and the electron injection layer can be a layer common to the light-receiving element and the light-emitting element. By having a common layer for the light-receiving element and the light-emitting element in this way, the number of film formations and the number of masks can be reduced, thereby reducing the manufacturing process and manufacturing costs of the display device. Furthermore, a display device having a light-receiving element can be manufactured using existing manufacturing equipment and manufacturing methods for display devices.

[0300] Next, a display device having light emitting and receiving elements and a light emitting element will be described. Note that the description of the same functions, actions, effects, etc. as those described above may be omitted.

[0301] In a display device according to one embodiment of the present invention, a subpixel that exhibits one of the colors has a light-emitting / receiving element instead of a light-emitting element, and a subpixel that exhibits the other color has a light-emitting element. The light-emitting / receiving element has both a function of emitting light (light-emitting function) and a function of receiving light (light-receiving function). For example, when a pixel has three subpixels, namely, a red subpixel, a green subpixel, and a blue subpixel, at least one subpixel has a light-emitting / receiving element, and the other subpixels have light-emitting elements. Therefore, the light-emitting / receiving portion of the display device according to one embodiment of the present invention has a function of displaying an image using both the light-emitting / receiving element and the light-emitting element.

[0302] By using a light-receiving / light-emitting element that serves as both a light-emitting element and a light-receiving element, a pixel can be given a light-receiving function without increasing the number of subpixels included in the pixel. This allows one or both of an imaging function and a sensing function to be added to the light-receiving / light-emitting portion of the display device while maintaining the aperture ratio of the pixel (aperture ratio of each subpixel) and the resolution of the display device. Therefore, the display device of one embodiment of the present invention can have a higher aperture ratio of the pixel and can easily achieve higher resolution than a display device in which a subpixel having a light-receiving element is provided separately from a subpixel having a light-emitting element.

[0303] In a display device according to one embodiment of the present invention, light-emitting and receiving elements and light-emitting elements are arranged in a matrix in a light-emitting and receiving portion, and an image can be displayed in the light-emitting and receiving portion. The light-emitting and receiving portion can be used as an image sensor, a touch sensor, or the like. In the display device according to one embodiment of the present invention, the light-emitting element can be used as a light source for the sensor. Therefore, imaging, detection of a touch operation, and the like can be performed even in a dark place.

[0304] Light-emitting and receiving elements can be fabricated by combining an organic EL element and an organic photodiode. For example, light-emitting and receiving elements can be fabricated by adding the active layer of an organic photodiode to the layered structure of an organic EL element. Furthermore, light-emitting and receiving elements fabricated by combining an organic EL element and an organic photodiode can suppress an increase in the number of film-forming steps by forming layers that can be configured in common with the organic EL element in a single step.

[0305] For example, one of the pair of electrodes (common electrode) may be a layer common to the light-emitting and light-emitting elements. Also, for example, at least one of the hole injection layer, hole transport layer, electron transport layer, and electron injection layer may be a layer common to the light-emitting and light-emitting elements.

[0306] Note that the layers of the light emitting / receiving element may have different functions depending on whether the light emitting / receiving element functions as a light receiving element or a light emitting element. In this specification, the components are referred to based on their functions when the light emitting / receiving element functions as a light emitting element.

[0307] The display device of this embodiment mode has a function of displaying an image using a light-emitting element and a light-emitting / light-emitting element. That is, the light-emitting element and the light-emitting / light-emitting element function as display elements.

[0308] The display device of this embodiment has a function of detecting light using a light receiving and emitting element, which can detect light having a shorter wavelength than light emitted by the light receiving and emitting element itself.

[0309] When the light-emitting / receiving elements are used as an image sensor, the display device of this embodiment can capture an image using the light-emitting / receiving elements. When the light-emitting / receiving elements are used as a touch sensor, the display device of this embodiment can detect a touch operation of an object using the light-emitting / receiving elements.

[0310] The light-receiving / light-emitting element functions as a photoelectric conversion element. The light-receiving / light-emitting element can be fabricated by adding an active layer of a light-receiving element to the configuration of the light-emitting element. For example, the active layer of a pn-type or pin-type photodiode can be used for the light-receiving / light-emitting element.

[0311] In particular, it is preferable to use an organic photodiode active layer having a layer containing an organic compound as the light-receiving / light-emitting element. 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 devices.

[0312] A display device, which is an example of a display device according to one embodiment of the present invention, will be described in more detail below with reference to drawings.

[0313] [Display device configuration example 1] [Configuration Example 1-1] 14A is a schematic diagram of a display panel 200. The display panel 200 includes a substrate 201, a substrate 202, a light receiving element 212, a light emitting element 211R, a light emitting element 211G, a light emitting element 211B, a functional layer 203, and the like.

[0314] The light-emitting element 211R, the light-emitting element 211G, the light-emitting element 211B, and the light-receiving element 212 are provided between the substrate 201 and the substrate 202. The light-emitting element 211R, the light-emitting element 211G, and the light-emitting element 211B emit red (R), green (G), or blue (B) light, respectively. Note that hereinafter, when there is no need to distinguish between the light-emitting element 211R, the light-emitting element 211G, and the light-emitting element 211B, they may be referred to as the light-emitting element 211.

[0315] The display panel 200 has a plurality of pixels arranged in a matrix. Each pixel has one or more sub-pixels. Each sub-pixel has one light-emitting element. For example, a pixel may have three sub-pixels (e.g., three colors of R, G, and B, or three colors of yellow (Y), cyan (C), and magenta (M)), or four sub-pixels (e.g., four colors of R, G, B, and white (W), or four colors of R, G, B, and Y). Each pixel also has a light-receiving element 212. The light-receiving element 212 may be provided in all pixels or in some of the pixels. Alternatively, one pixel may have multiple light-receiving elements 212.

[0316] 14A shows a state in which finger 220 touches the surface of substrate 202. A portion of the light emitted by light-emitting element 211G is reflected at the contact point between substrate 202 and finger 220. A portion of the reflected light is then incident on light-receiving element 212, thereby making it possible to detect that finger 220 has touched substrate 202. In other words, display panel 200 can function as a touch panel.

[0317] The functional layer 203 has a circuit for driving the light-emitting element 211R, the light-emitting element 211G, and the light-emitting element 211B, and a circuit for driving the light-receiving element 212. The functional layer 203 is provided with switches, transistors, capacitors, wiring, and the like. Note that when the light-emitting element 211R, the light-emitting element 211G, the light-emitting element 211B, and the light-receiving element 212 are driven by a passive matrix method, a configuration without switches, transistors, and the like may be adopted.

[0318] It is preferable that the display panel 200 has a function of detecting the fingerprint of a finger 220. Fig. 14B is a schematic enlarged view of a contact portion when the finger 220 is touching the substrate 202. Fig. 14B also shows light emitting elements 211 and light receiving elements 212 arranged alternately.

[0319] A fingerprint is formed by concave and convex portions of finger 220. Therefore, the convex portions of the fingerprint are in contact with substrate 202 as shown in FIG.

[0320] Light reflected from a surface, interface, etc. can be classified as specular reflection or diffuse reflection. Specular reflection is highly directional light, in which the angle of incidence and the angle of reflection are the same, while diffuse reflection is low-directional light, in which the intensity is less dependent on the angle. The diffuse reflection component is dominant in the light reflected from the surface of the finger 220. On the other hand, the specular reflection component is dominant in the light reflected from the interface between the substrate 202 and the atmosphere.

[0321] The intensity of light reflected by the contact or non-contact surface between finger 220 and substrate 202 and incident on light receiving element 212 located directly below them is the sum of specularly reflected light and diffusely reflected light. As described above, at the concave portions of finger 220, substrate 202 and finger 220 do not come into contact, so specularly reflected light (indicated by solid arrows) is dominant, whereas at the convex portions, they come into contact, so diffusely reflected light (indicated by dashed arrows) from finger 220 is dominant. Therefore, the intensity of light received by light receiving element 212 located directly below the concave portions is higher than that of light receiving element 212 located directly below the convex portions. This makes it possible to capture an image of the fingerprint of finger 220.

[0322] A clear fingerprint image can be obtained by arranging the light receiving elements 212 at an interval smaller than the distance between two convex portions of a fingerprint, preferably the distance between adjacent concave and convex portions. Since the distance between concave and convex portions of a human fingerprint is approximately 200 μm, for example, the interval between the light receiving elements 212 is 400 μm or less, preferably 200 μm or less, more preferably 150 μm or less, even more preferably 100 μm or less, and even more preferably 50 μm or less, and is 1 μm or more, preferably 10 μm or more, and more preferably 20 μm or more.

[0323] Fig. 14C shows an example of a fingerprint image captured by display panel 200. In Fig. 14C, the outline of finger 220 is indicated by a dashed line and the outline of contact area 221 is indicated by a dashed line within imaging range 223. Within contact area 221, a fingerprint 222 with high contrast can be captured due to differences in the amount of light incident on light receiving element 212.

[0324] The display panel 200 can also function as a touch panel or a pen tablet. Fig. 14D shows a state in which the tip of a stylus 225 is in contact with the substrate 202 and is slid in the direction of the dashed arrow.

[0325] As shown in Figure 14D, the diffuse reflected light scattered by the tip of stylus 225 and the contact surface of substrate 202 is incident on light receiving element 212 located at the part overlapping with the contact surface, thereby enabling the position of the tip of stylus 225 to be detected with high accuracy.

[0326] 14E shows an example of a trajectory 226 of the stylus 225 detected by the display panel 200. The display panel 200 is capable of detecting the position of a detectable object such as the stylus 225 with high positional accuracy, and therefore is also capable of performing high-resolution drawing in a drawing application or the like. Furthermore, unlike the case where a capacitance-type touch sensor, an electromagnetic induction-type touch pen, or the like is used, the position of even a highly insulating detectable object can be detected, and therefore the material of the tip of the stylus 225 is not a factor, and various writing implements (for example, a brush, a glass pen, a feather pen, etc.) can be used.

[0327] 14F to 14H show an example of a pixel that can be applied to the display panel 200. FIG.

[0328] 14F and 14G each have a red (R) light-emitting element 211R, a green (G) light-emitting element 211G, a blue (B) light-emitting element 211B, and a light-receiving element 212. The pixel has a pixel circuit for driving the light-emitting element 211R, the light-emitting element 211G, the light-emitting element 211B, and the light-receiving element 212, respectively.

[0329] Fig. 14F shows an example in which three light-emitting elements and one light-receiving element are arranged in a 2 x 2 matrix. Fig. 14G shows an example in which three light-emitting elements are arranged in a row, and one horizontally elongated light-receiving element 212 is arranged below them.

[0330] 14H is an example of a pixel having a white (W) light-emitting element 211W. Here, four light-emitting elements are arranged in a row, and a light-receiving element 212 is arranged below them.

[0331] The pixel configuration is not limited to the above, and various arrangement methods can be adopted.

[0332] [Configuration Example 1-2] In the following, an example of a configuration including a light-emitting element that emits visible light, a light-emitting element that emits infrared light, and a light-receiving element will be described.

[0333] The display panel 200A shown in Fig. 15A has a light-emitting element 211IR in addition to the configuration exemplified in Fig. 14A. The light-emitting element 211IR is a light-emitting element that emits infrared light IR. In this case, it is preferable to use an element that can receive at least the infrared light IR emitted by the light-emitting element 211IR as the light-receiving element 212. It is more preferable to use an element that can receive both visible light and infrared light as the light-receiving element 212.

[0334] As shown in FIG. 15A, when a finger 220 touches the substrate 202, infrared light IR emitted from the light-emitting element 211IR is reflected by the finger 220, and a portion of the reflected light is incident on the light-receiving element 212, thereby obtaining position information of the finger 220.

[0335] 15B to 15D show examples of pixels applicable to the display panel 200A.

[0336] Fig. 15B shows an example in which three light-emitting elements are arranged in a row, and below them, light-emitting element 211IR and light-receiving element 212 are arranged side by side. Fig. 15C shows an example in which four light-emitting elements including light-emitting element 211IR are arranged in a row, and below them, light-receiving element 212 is arranged.

[0337] FIG. 15D shows an example in which three light emitting elements and a light receiving element 212 are arranged on all four sides with a light emitting element 211IR at the center.

[0338] In the pixels shown in FIGS. 15B to 15D, the positions of the light-emitting elements and the light-emitting elements and the light-receiving elements can be interchanged.

[0339] [Configuration Example 1-3] In the following, an example of a configuration including a light-emitting element that emits visible light and a light-receiving / light-emitting element that emits visible light and receives visible light will be described.

[0340] The display panel 200B shown in FIG. 16A includes a light-emitting element 211B, a light-emitting element 211G, and a light-receiving / light-emitting element 213R. The light-receiving / light-emitting element 213R functions as a light-emitting element that emits red (R) light and as a photoelectric conversion element that receives visible light. FIG. 16A shows an example in which the light-receiving / light-emitting element 213R receives green (G) light emitted by the light-emitting element 211G. The light-receiving / light-emitting element 213R may also receive blue (B) light emitted by the light-emitting element 211B. The light-receiving / light-emitting element 213R may also receive both green light and blue light.

[0341] For example, it is preferable that the light receiving / emitting element 213R receives light with a shorter wavelength than the light it emits. Alternatively, the light receiving / emitting element 213R may be configured to receive light with a longer wavelength than the light it emits (for example, infrared light). The light receiving / emitting element 213R may be configured to receive light with a wavelength similar to the light it emits, but in that case, it may also receive the light it emits, which could reduce the light emission efficiency. Therefore, it is preferable that the light receiving / emitting element 213R is configured so that the peak of the emission spectrum and the peak of the absorption spectrum do not overlap as much as possible.

[0342] In addition, the light emitted by the light emitting / receiving element is not limited to red light. Furthermore, the light emitted by the light emitting element is not limited to a combination of green light and blue light. For example, the light emitting / receiving element may be an element that emits green or blue light and receives light of a wavelength different from the light it emits.

[0343] In this way, by having the light emitting / receiving element 213R function as both a light emitting element and a light receiving element, the number of elements arranged in one pixel can be reduced, which makes it easier to achieve higher definition, a higher aperture ratio, and higher resolution.

[0344] 16B to 16I show an example of a pixel that can be applied to the display panel 200B.

[0345] Fig. 16B shows an example in which the light emitting / receiving element 213R, the light emitting element 211G, and the light emitting element 211B are arranged in a row. Fig. 16C shows an example in which the light emitting element 211G and the light emitting element 211B are arranged alternately in the vertical direction, and the light emitting / receiving element 213R is arranged next to them.

[0346] FIG. 16D shows an example in which three light-emitting elements (light-emitting element 211G, light-emitting element 211B, and light-emitting element 211X) and one light-receiving / light-emitting element are arranged in a 2×2 matrix. Light-emitting element 211X is an element that emits light other than R, G, and B. Examples of light other than R, G, and B include white (W), yellow (Y), cyan (C), magenta (M), infrared light (IR), and ultraviolet light (UV). When light-emitting element 211X emits infrared light, it is preferable that the light-receiving / light-emitting element has a function of detecting infrared light or a function of detecting both visible light and infrared light. The wavelength of light detected by the light-receiving / light-emitting element can be determined depending on the application of the sensor.

[0347] FIG. 16E shows two pixels. An area including three elements surrounded by dotted lines corresponds to one pixel. Each pixel has a light-emitting element 211G, a light-emitting element 211B, and an optical element 213R. In the left pixel shown in FIG. 16E, the light-emitting element 211G is arranged in the same row as the optical element 213R, and the light-emitting element 211B is arranged in the same column as the optical element 213R. In the right pixel shown in FIG. 16E, the light-emitting element 211G is arranged in the same row as the optical element 213R, and the light-emitting element 211B is arranged in the same column as the optical element 211G. In the pixel layout shown in FIG. 16E, the optical element 213R, the light-emitting element 211G, and the light-emitting element 211B are arranged repeatedly in both odd-numbered and even-numbered rows, and in each column, light-emitting elements or optical elements of different colors are arranged in the odd-numbered and even-numbered rows.

[0348] Figure 16F shows four pixels in a Pentile arrangement, with adjacent pixels each having a light-emitting or light-receiving element that emits two different colors of light. Figure 16F also shows the top view of the light-emitting or light-receiving element.

[0349] The upper left pixel and lower right pixel shown in Fig. 16F have a light emitting / receiving element 213R and a light emitting element 211G. The upper right pixel and lower left pixel have a light emitting element 211G and a light emitting element 211B. That is, in the example shown in Fig. 16F, a light emitting element 211G is provided in each pixel.

[0350] The top surface shapes of the light-emitting element and light-receiving / light-emitting element are not particularly limited and may be circular, elliptical, polygonal, polygonal with rounded corners, etc. Figure 16F etc. shows an example in which the top surface shapes of the light-emitting element and light-receiving / light-emitting element are squares (diamonds) tilted at approximately 45 degrees. Note that the top surface shapes of the light-emitting element and light-receiving / light-emitting element for each color may be different from each other, or may be the same for some or all of the colors.

[0351] Furthermore, the sizes of the light-emitting regions (or light-receiving and light-emitting regions) of the light-emitting elements and light-receiving and light-emitting elements of each color may be different from each other, or may be the same for some or all colors. For example, in FIG. 16F, the area of ​​the light-emitting region of the light-emitting element 211G provided in each pixel may be smaller than the light-emitting regions (or light-receiving and light-emitting regions) of the other elements.

[0352] Fig. 16G is a modified example of the pixel array shown in Fig. 16F. Specifically, the configuration in Fig. 16G is obtained by rotating the configuration in Fig. 16F by 45 degrees. Although Fig. 16F has been described as having two elements per pixel, it can also be understood that one pixel is made up of four elements, as shown in Fig. 16G.

[0353] Fig. 16H is a modified example of the pixel array shown in Fig. 16F. The upper left pixel and lower right pixel shown in Fig. 16H have light emitting / receiving elements 213R and light emitting elements 211G. The upper right pixel and lower left pixel have light emitting / receiving elements 213R and light emitting elements 211B. That is, in the example shown in Fig. 16H, each pixel is provided with a light emitting / receiving element 213R. Because each pixel is provided with a light emitting / receiving element 213R, the configuration shown in Fig. 16H can capture images with higher resolution than the configuration shown in Fig. 16F. This can improve the accuracy of biometric authentication, for example.

[0354] FIG. 16I is a modified example of the pixel array shown in FIG. 16H, and is obtained by rotating the pixel array by 45 degrees.

[0355] In FIG. 16I, a description will be given assuming that one pixel is composed of four elements (two light-emitting elements and two light-receiving and light-emitting elements). In this way, one pixel has multiple light-receiving and light-emitting elements with a light-receiving function, allowing for imaging with high resolution. This can improve the accuracy of biometric authentication. For example, the resolution of imaging can be set to the root double of the resolution of display.

[0356] A display device to which the configuration shown in Figure 16H or Figure 16I is applied has p (p is an integer of 2 or more) first light-emitting elements, q (q is an integer of 2 or more) second light-emitting elements, and r (r is an integer greater than p and greater than q) light-receiving and light-emitting elements. p and r satisfy r = 2p. Furthermore, p, q, and r satisfy r = p + q. One of the first light-emitting elements and the second light-emitting element emits green light, and the other emits blue light. The light-receiving and light-emitting element emits red light and has a light-receiving function.

[0357] For example, when detecting a touch operation using a light-emitting / receiving element, it is preferable that the light emitted from the light source is less visible to the user. Because blue light is less visible than green light, it is preferable that a light-emitting element that emits blue light be used as the light source. Therefore, it is preferable that the light-emitting / receiving element has a function of receiving blue light. However, this is not limited to this, and the light-emitting element used as the light source can be appropriately selected depending on the sensitivity of the light-emitting / receiving element.

[0358] As described above, pixels with various arrangements can be applied to the display device of this embodiment mode.

[0359] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0360] (Fourth embodiment) In this embodiment, a light-emitting element (also referred to as a light-emitting device) and a light-receiving element (also referred to as a light-receiving device) that can be used for a light-emitting and receiving device that is one embodiment of the present invention will be described.

[0361] 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.

[0362] 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.

[0363] 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.

[0364] 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.

[0365] 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.

[0366] [Device Structure] Next, detailed structures of a light-emitting element, a light-receiving element, and a light-emitting and light-emitting element that can be used in the display device of one embodiment of the present invention will be described.

[0367] The display device of one embodiment of the present invention may be any of a top emission type that emits light in a direction opposite to a substrate on which a light-emitting element is formed, a bottom emission type that emits light toward a substrate on which a light-emitting element is formed, and a dual emission type that emits light to both sides.

[0368] In this embodiment, a top-emission display device will be described as an example.

[0369] In this specification, unless otherwise specified, even when describing a configuration having a plurality of elements (e.g., light-emitting elements, light-emitting layers), when describing matters common to each element, the alphabet will be omitted. For example, when describing matters common to light-emitting layer 383R and light-emitting layer 383G, etc., they may be referred to as light-emitting layer 383.

[0370] A display device 380A shown in FIG. 17A includes a light receiving element 370PD, a light emitting element 370R that emits red (R) light, a light emitting element 370G that emits green (G) light, and a light emitting element 370B that emits blue (B) light.

[0371] Each light-emitting element has a pixel electrode 371, a hole injection layer 381, a hole transport layer 382, ​​a light-emitting layer, an electron transport layer 384, an electron injection layer 385, and a common electrode 375 stacked in this order. Light-emitting element 370R has a light-emitting layer 383R, light-emitting element 370G has a light-emitting layer 383G, and light-emitting element 370B has a light-emitting layer 383B. Light-emitting layer 383R contains a light-emitting material that emits red light, light-emitting layer 383G contains a light-emitting material that emits green light, and light-emitting layer 383B contains a light-emitting material that emits blue light.

[0372] The light emitting element is an electroluminescent element that emits light toward the common electrode 375 when a voltage is applied between the pixel electrode 371 and the common electrode 375 .

[0373] The light receiving element 370PD has a pixel electrode 371, a hole injection layer 381, a hole transport layer 382, ​​an active layer 373, an electron transport layer 384, an electron injection layer 385, and a common electrode 375 stacked in this order.

[0374] The light receiving element 370PD is a photoelectric conversion element that receives light incident from outside the display device 380A and converts it into an electrical signal.

[0375] In this embodiment, in both the light-emitting element and the light-receiving element, the pixel electrode 371 functions as an anode and the common electrode 375 functions as a cathode. In other words, by applying a reverse bias between the pixel electrode 371 and the common electrode 375 and driving the light-receiving element, the light-receiving element can detect light incident on the light-receiving element, generate electric charges, and extract the electric charges as a current.

[0376] In the display device of this embodiment, an organic compound is used for the active layer 373 of the light-receiving element 370PD. The layers of the light-receiving element 370PD other than the active layer 373 can be configured in common with the light-emitting element. Therefore, by simply adding a step of forming the active layer 373 to the manufacturing process of the light-emitting element, the light-receiving element 370PD can be formed in parallel with the formation of the light-emitting element. Furthermore, the light-emitting element and the light-receiving element 370PD can be formed on the same substrate. Therefore, the light-receiving element 370PD can be built into the display device without significantly increasing the number of manufacturing steps.

[0377] In the display device 380A, the light receiving element 370PD and the light emitting element have a common configuration, except that the active layer 373 of the light receiving element 370PD and the light emitting layer 383 of the light emitting element are fabricated separately. However, the configuration of the light receiving element 370PD and the light emitting element is not limited to this. The light receiving element 370PD and the light emitting element may have layers fabricated separately from each other, in addition to the active layer 373 and the light emitting layer 383. It is preferable that the light receiving element 370PD and the light emitting element have one or more layers used in common (common layers). This allows the light receiving element 370PD to be incorporated into the display device without significantly increasing the number of manufacturing steps.

[0378] A conductive film that transmits visible light is used for the electrode from which light is extracted, between the pixel electrode 371 and the common electrode 375. It is preferable to use a conductive film that reflects visible light for the electrode from which light is not extracted.

[0379] The light-emitting element included in the display device of this embodiment preferably has a micro-optical resonator (microcavity) structure. Therefore, one of a pair of electrodes included in the light-emitting element preferably has an electrode that is transparent and reflective to visible light (semi-transmissive / semi-reflective electrode), and the other preferably has an electrode that is reflective to visible light (reflective electrode). When the light-emitting element has a microcavity structure, light emitted from the light-emitting layer can be resonated between both electrodes, thereby intensifying the light emitted from the light-emitting element.

[0380] The semi-transmitting / semi-reflective electrode can have a laminated structure of a reflective electrode and an electrode that is transparent to visible light (also called a transparent electrode).

[0381] The light transmittance of the transparent electrode is 40% or more. For example, it is preferable to use an electrode with a visible light (light with a wavelength of 400 nm or more and less than 750 nm) transmittance of 40% or more for the light emitting element. The visible light reflectance of the semi-transmissive / semi-reflective electrode is 10% or more and 95% or less, preferably 30% or more and 80% or less. The visible light reflectance of the reflective electrode is 40% or more and 100% or less, preferably 70% or more and 100% or less. In addition, the resistivity of these electrodes is 1×10 -2 When the light-emitting element emits near-infrared light (light with a wavelength of 750 nm or more and 1300 nm or less), the transmittance or reflectance of these electrodes for near-infrared light preferably satisfies the above-mentioned numerical range, similar to the transmittance or reflectance for visible light.

[0382] The light-emitting element has at least a light-emitting layer 383. The light-emitting element may further have, in addition to the light-emitting layer 383, a layer containing a substance having a high hole-injecting property, a substance having a high hole-transporting property, a hole-blocking material, a substance having a high electron-transporting property, a substance having a high electron-injecting property, an electron-blocking material, a bipolar substance (a substance having a high electron-transporting property and a high hole-transporting property), or the like.

[0383] For example, the light-emitting element and the light-receiving element may have one or more layers of the hole injection layer, hole transport layer, electron transport layer, and electron injection layer in common, or the light-emitting element and the light-receiving element may have one or more layers of the hole injection layer, hole transport layer, electron transport layer, and electron injection layer formed differently from each other.

[0384] 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 or a composite material containing a hole transport material and an acceptor material (electron acceptor material).

[0385] In a light-emitting element, the hole transport layer is a layer that transports holes injected from the anode by the hole injection layer to the light-emitting layer. In a light-receiving element, the hole transport layer is a layer that transports holes generated in the active layer based on incident light to the anode. 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 2 A 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.

[0386] In a light-emitting element, the electron transport layer is a layer that transports electrons injected from the cathode by the electron injection layer to the light-emitting layer. In a light-receiving element, the electron transport layer is a layer that transports electrons generated in the active layer based on incident light to the cathode. The electron transport layer is a layer that contains an electron transporting material. The electron transporting material is a material having a 1×10 -6 cm 2A 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.

[0387] 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).

[0388] The light-emitting layer 383 is a layer containing a light-emitting substance. The light-emitting layer 383 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.

[0389] Examples of light-emitting materials include fluorescent materials, phosphorescent materials, TADF materials, and quantum dot materials.

[0390] 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.

[0391] 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.

[0392] The light-emitting layer 383 may contain one or more organic compounds (host materials, assist materials, etc.) in addition to a light-emitting substance (guest material). As the one or more organic compounds, one or both of a hole-transporting material and an electron-transporting material can be used. Furthermore, as the one or more organic compounds, a bipolar material or a TADF material can be used.

[0393] The light-emitting layer 383 preferably includes, 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 structure allows efficient emission using Exciplex-Triplet Energy Transfer (ExTET), which is energy transfer from an exciplex to a light-emitting substance (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 substance, the energy transfer becomes smooth, allowing efficient emission. This structure simultaneously enables high efficiency, low-voltage operation, and long life of the light-emitting element.

[0394] As a combination of materials that form an exciplex, it is preferable that the HOMO level (highest occupied molecular orbital level) of the hole-transporting material is equal to or higher than the HOMO level of the electron-transporting material. It is also preferable that the LUMO level (lowest unoccupied molecular orbital level) of the hole-transporting material is equal to or higher than the LUMO level of the electron-transporting material. The LUMO level and HOMO level of the material can be derived from the electrochemical properties (reduction potential and oxidation potential) of the material measured by cyclic voltammetry (CV).

[0395] The formation of exciplexes can be confirmed, for example, by comparing the emission spectra of the hole-transporting material, the electron-transporting material, and the mixed film of these materials and observing the phenomenon that the emission spectrum of the mixed film is shifted to longer wavelengths than the emission spectra of each material (or has a new peak at longer wavelengths). Alternatively, it can be confirmed by comparing the transient photoluminescence (PL) of the hole-transporting material, the transient PL of the electron-transporting material, and the mixed film of these materials and observing differences in transient response, such as the transient PL lifetime of the mixed film having a longer-lived component or a larger proportion of delayed components than the transient PL lifetimes of the individual materials. The above-mentioned transient PL can also be interpreted as transient electroluminescence (EL). In other words, the formation of exciplexes can also be confirmed by comparing the transient EL of the hole-transporting material, the transient EL of the electron-transporting material, and the mixed film of these materials and observing differences in transient response.

[0396] The active layer 373 includes a semiconductor. Examples of the semiconductor include an inorganic semiconductor such as silicon and an organic semiconductor including an organic compound. In this embodiment, an example in which an organic semiconductor is used as the semiconductor included in the active layer 373 is shown. By using an organic semiconductor, the light-emitting layer 383 and the active layer 373 can be formed by the same method (for example, vacuum evaporation), which is preferable because a common manufacturing device can be used.

[0397] The active layer 373 has an n-type semiconductor material, such as fullerene (e.g., C 60 , C 70Examples 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 across a plane, as in benzene, the electron-donating (donor) properties increase, but fullerenes have a spherical shape, so they have high electron-accepting properties despite the wide spread π-electron conjugation. High electron-accepting properties allow charge separation to occur quickly and efficiently, making them useful as light-receiving elements. C 60 , C 70 Both 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 broad absorption band in the long wavelength region compared to [6,6]-Phenyl-C71-butyric acid methyl ester (abbreviation: PC70BM), [6,6]-Phenyl-C61-butyric acid methyl ester (abbreviation: PC60BM), and 1',1'',4',4''-Tetrahydro-di[1,4]methanonaphthaleno[1,2:2',3',56,60:2'',3''][5,6]fullerene-C60 (abbreviation: ICBA).

[0398] Furthermore, examples of n-type semiconductor materials include perylene tetracarboxylic acid derivatives such as N,N'-dimethyl-3,4,9,10-perylene tetracarboxylic acid diimide (abbreviation: Me-PTCDI).

[0399] Furthermore, examples of n-type semiconductor materials include 2,2'-(5,5'-(thieno[3,2-b]thiophene-2,5-diyl)bis(thiophene-5,2-diyl))bis(methane-1-yl-1-ylidene)dimalononitrile (abbreviation: FT2TDMN).

[0400] 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.

[0401] Examples of the p-type semiconductor material of the active layer 373 include electron-donating organic semiconductor materials such as copper(II) phthalocyanine (CuPc), tetraphenyldibenzoperiflanthene (DBP), zinc phthalocyanine (ZnPc), tin phthalocyanine (SnPc), quinacridone, and rubrene.

[0402] Examples of p-type semiconductor materials include carbazole derivatives, thiophene derivatives, furan derivatives, and compounds having an aromatic amine skeleton. 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, rubrene derivatives, tetracene derivatives, polyphenylenevinylene derivatives, polyparaphenylene derivatives, polyfluorene derivatives, polyvinylcarbazole derivatives, and polythiophene derivatives.

[0403] 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.

[0404] 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.

[0405] For example, the active layer 373 is preferably formed by co-evaporating an n-type semiconductor and a p-type semiconductor, or alternatively, the active layer 373 may be formed by laminating an n-type semiconductor and a p-type semiconductor.

[0406] The light-emitting element and the light-receiving element 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 element and the light-receiving element can be formed by a method such as vapor deposition (including vacuum vapor deposition), a transfer method, a printing method, an inkjet method, or a coating method.

[0407] 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 or electron blocking materials. Furthermore, inorganic compounds such as zinc oxide (ZnO) and organic compounds such as polyethyleneimine ethoxylate (PEIE) can be used as electron transporting or hole blocking materials. The light-receiving device may have, for example, a mixed film of PEIE and ZnO.

[0408] Furthermore, 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, can be used for the active layer 373. For example, a method of dispersing an acceptor material in PBDB-T or a PBDB-T derivative can be used.

[0409] Display device 380B shown in FIG. 17B differs from display device 380A in that light receiving element 370PD and light emitting element 370R have the same configuration.

[0410] The light receiving element 370PD and the light emitting element 370R have the active layer 373 and the light emitting layer 383R in common.

[0411] Here, it is preferable that light receiving element 370PD has the same configuration as a light emitting element that emits light of a longer wavelength than the light to be detected. For example, light receiving element 370PD configured to detect blue light can have the same configuration as one or both of light emitting element 370R and light emitting element 370G. For example, light receiving element 370PD configured to detect green light can have the same configuration as light emitting element 370R.

[0412] By using a common structure for the light-receiving element 370PD and the light-emitting element 370R, the number of film-forming steps and the number of masks can be reduced compared to a structure in which the light-receiving element 370PD and the light-emitting element 370R have separate layers, thereby reducing the manufacturing steps and manufacturing costs of the display device.

[0413] Furthermore, by using a common configuration for the light receiving element 370PD and the light emitting element 370R, the margin for misalignment can be narrowed compared to a configuration in which the light receiving element 370PD and the light emitting element 370R have separate layers. This allows for an increased pixel aperture ratio and improved light extraction efficiency of the display device. This also extends the life of the light emitting element. Furthermore, the display device can display high brightness. Furthermore, it also allows for higher resolution of the display device.

[0414] Light-emitting layer 383R includes a light-emitting material that emits red light. Active layer 373 includes an organic compound that absorbs light with a wavelength shorter than red (for example, one or both of green light and blue light). Active layer 373 preferably includes an organic compound that does not easily absorb red light and absorbs light with a wavelength shorter than red. This allows red light to be extracted efficiently from light-emitting element 370R, and light-receiving element 370PD to detect light with a wavelength shorter than red with high accuracy.

[0415] Furthermore, in the display device 380B, an example is shown in which the light emitting element 370R and the light receiving element 370PD have the same configuration, but the light emitting element 370R and the light receiving element 370PD may have optical adjustment layers of different thicknesses.

[0416] 18A and 18B includes a light receiving / emitting element 370SR that emits red (R) light and has a light receiving function, a light emitting element 370G, and a light emitting element 370B. The configuration of the light emitting element 370G and the light emitting element 370B can be based on the configuration of the display device 380A described above.

[0417] The light emitting / receiving element 370SR has, stacked in this order, a pixel electrode 371, a hole injection layer 381, a hole transport layer 382, ​​an active layer 373, a light emitting layer 383R, an electron transport layer 384, an electron injection layer 385, and a common electrode 375. The light emitting / receiving element 370SR has the same configuration as the light emitting element 370R and the light receiving element 370PD exemplified in the display device 380B.

[0418] 18A shows a case where the light emitting / receiving element 370SR functions as a light emitting element. In FIG. 18A, an example is shown in which the light emitting element 370B emits blue light, the light emitting element 370G emits green light, and the light emitting / receiving element 370SR emits red light.

[0419] Fig. 18B shows a case where the light receiving / emitting element 370SR functions as a light receiving element. Fig. 18B shows an example where the light receiving / emitting element 370SR receives blue light emitted by the light emitting element 370B and green light emitted by the light emitting element 370G.

[0420] The light emitting element 370B, the light emitting element 370G, and the light emitting / receiving element 370SR each have a pixel electrode 371 and a common electrode 375. In this embodiment, a case will be described in which the pixel electrode 371 functions as an anode and the common electrode 375 functions as a cathode. The light emitting / receiving element 370SR is driven by applying a reverse bias between the pixel electrode 371 and the common electrode 375, so that the light emitting / receiving element 370SR can detect light incident on the light emitting / receiving element 370SR, generate electric charges, and extract the charges as a current.

[0421] The light emitting / receiving element 370SR can be said to have a configuration in which an active layer 373 is added to a light emitting element. In other words, the light emitting / receiving element 370SR can be formed in parallel with the formation of the light emitting element by simply adding a step of forming the active layer 373 to the manufacturing process of the light emitting element. Furthermore, the light emitting element and the light emitting / receiving element can be formed on the same substrate. Therefore, it is possible to provide the display unit with either or both of an imaging function and a sensing function without significantly increasing the manufacturing process.

[0422] There are no limitations on the stacking order of the light-emitting layer 383R and the active layer 373. Figures 18A and 18B show an example in which the active layer 373 is provided on the hole-transport layer 382, ​​and the light-emitting layer 383R is provided on the active layer 373. The stacking order of the light-emitting layer 383R and the active layer 373 may be reversed.

[0423] Furthermore, the light emitting / receiving element may not have at least one layer selected from the hole injection layer 381, the hole transport layer 382, ​​the electron transport layer 384, and the electron injection layer 385. The light emitting / receiving element may also have other functional layers such as a hole blocking layer and an electron blocking layer.

[0424] In the light emitting / receiving element, a conductive film that transmits visible light is used for the electrode on the light extraction side, and a conductive film that reflects visible light is preferably used for the electrode on the non-light extraction side.

[0425] The functions and materials of the layers constituting the light emitting / receiving element are similar to those of the layers constituting the light emitting element and the light receiving element, and therefore detailed description thereof will be omitted.

[0426] 18C to 18G show examples of the stacked structure of the light emitting and receiving element.

[0427] The light emitting / receiving element shown in FIG. 18C includes a first electrode 377, a hole injection layer 381, a hole transport layer 382, ​​a light emitting layer 383R, an active layer 373, an electron transport layer 384, an electron injection layer 385, and a second electrode 378.

[0428] FIG. 18C shows an example in which a light-emitting layer 383R is provided on a hole-transporting layer 382, ​​and an active layer 373 is laminated on the light-emitting layer 383R.

[0429] As shown in FIGS. 18A to 18C, the active layer 373 and the light-emitting layer 383R may be in contact with each other.

[0430] A buffer layer is preferably provided between the active layer 373 and the light-emitting layer 383R. In this case, the buffer layer preferably has hole-transporting and electron-transporting properties. For example, a bipolar substance is preferably used for the buffer layer. Alternatively, the buffer layer may be at least one layer selected from a hole-injection layer, a hole-transporting layer, an electron-transporting layer, an electron-injection layer, a hole-blocking layer, and an electron-blocking layer. FIG. 18D shows an example in which a hole-transporting layer 382 is used as the buffer layer.

[0431] By providing a buffer layer between the active layer 373 and the light-emitting layer 383R, it is possible to suppress the transfer of excitation energy from the light-emitting layer 383R to the active layer 373. In addition, the buffer layer can be used to adjust the optical path length (cavity length) of the microcavity structure. Therefore, a light-emitting / receiving element having a buffer layer between the active layer 373 and the light-emitting layer 383R can obtain high light-emitting efficiency.

[0432] FIG. 18E shows an example of a laminated structure in which a hole transport layer 382-1, an active layer 373, a hole transport layer 382-2, and an emitting layer 383R are laminated in this order on a hole injection layer 381. The hole transport layer 382-2 functions as a buffer layer. The hole transport layer 382-1 and the hole transport layer 381-2 may contain the same material or different materials. Alternatively, a layer that can be used as the buffer layer described above may be used instead of the hole transport layer 381-2. Alternatively, the positions of the active layer 373 and the emitting layer 383R may be interchanged.

[0433] 18F differs from the light emitting / receiving element shown in Fig. 18A in that it does not have the hole transport layer 382. In this way, the light emitting / receiving element may not have at least one layer among the hole injection layer 381, the hole transport layer 382, ​​the electron transport layer 384, and the electron injection layer 385. The light emitting / receiving element may also have other functional layers such as a hole blocking layer or an electron blocking layer.

[0434] The light emitting / receiving device shown in FIG. 18G differs from the light emitting / receiving device shown in FIG. 18A in that it does not have an active layer 373 and a light emitting layer 383R, but has a layer 389 that serves as both a light emitting layer and an active layer.

[0435] The layer that serves as both the light-emitting layer and the active layer can be, for example, a layer containing three materials: an n-type semiconductor that can be used for the active layer 373, a p-type semiconductor that can be used for the active layer 373, and a light-emitting substance that can be used for the light-emitting layer 383R.

[0436] It is preferable that the lowest energy absorption band in the absorption spectrum of the mixed material of n-type and p-type semiconductors does not overlap with the maximum peak in the emission spectrum (PL spectrum) of the luminescent substance, and it is more preferable that they are sufficiently separated from each other.

[0437] (Embodiment 5) In this embodiment, an example of a display device including a light-receiving device or the like according to one embodiment of the present invention will be described.

[0438] 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.

[0439] 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.

[0440] Examples of the top surface shape of the sub-pixel include polygons such as triangles, quadrilaterals (including rectangles and squares), and pentagons, as well as polygons with rounded corners, ellipses, circles, etc. The top surface shape of the sub-pixels here corresponds to the top surface shape of the light-emitting region of the light-emitting device.

[0441] 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.

[0442] The pixel shown in FIGS. 19A, 19B, and 19C includes a subpixel G, a subpixel B, a subpixel R, and a subpixel PS.

[0443] A stripe arrangement is applied to the pixels shown in Fig. 19A, and a matrix arrangement is applied to the pixels shown in Fig. 19B.

[0444] The pixel array shown in FIG. 19C has a configuration in which three subpixels (subpixel R, subpixel G, and subpixel S) are vertically arranged next to one subpixel (subpixel B).

[0445] The pixel shown in FIGS. 19D, 19E, and 19F has a subpixel G, a subpixel B, a subpixel R, a subpixel IR, and a subpixel PS.

[0446] 19D, 19E, and 19F show examples in which one pixel is arranged across two rows. The top row (first row) has three subpixels (subpixel G, subpixel B, and subpixel R), and the bottom row (second row) has two subpixels (one subpixel PS and one subpixel IR).

[0447] In Fig. 19D, three vertically elongated subpixels G, B, and R are arranged horizontally, with a subpixel PS and a horizontally elongated subpixel IR arranged horizontally below them. In Fig. 19E, two horizontally elongated subpixels G and R are arranged vertically, with a vertically elongated subpixel B arranged horizontally next to them, and a horizontally elongated subpixel IR and a vertically elongated subpixel PS arranged horizontally below them. In Fig. 19F, three vertically elongated subpixels R, G, and B are arranged horizontally, with a horizontally elongated subpixel IR and a vertically elongated subpixel PS arranged horizontally below them. Figs. 19E and 19F show the case where the area of ​​the subpixel IR is the largest and the area of ​​the subpixel PS is approximately the same as that of the other subpixels.

[0448] The layout of the sub-pixels is not limited to the configurations shown in FIGS. 19A to 19F.

[0449] Subpixel R has a light-emitting device that emits red light. Subpixel G has a light-emitting device that emits green light. Subpixel B has a light-emitting device that emits blue light. Subpixel IR has a light-emitting device that emits infrared light. Subpixel PS has a light-receiving device. The wavelength of light detected by subpixel PS is not particularly limited, but it is preferable that the light-receiving device of subpixel PS is sensitive to light emitted by the light-emitting device of subpixel R, subpixel G, subpixel B, or subpixel IR. For example, it is preferable to detect one or more of light in wavelength ranges such as blue, purple, blue-purple, green, yellow-green, yellow, orange, and red, and light in the infrared wavelength range.

[0450] The light-receiving area of ​​the subpixel PS is smaller than the light-emitting area of ​​the other subpixels. The smaller the light-receiving area, the narrower the imaging range, which makes it possible to suppress blurring in the imaging results and improve resolution. Therefore, by using the subpixel PS, high-definition or high-resolution imaging can be performed. For example, the subpixel 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.

[0451] The subpixel PS can also 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). For example, it is preferable for the subpixel PS to detect infrared light, which enables touch detection even in dark places.

[0452] 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.

[0453] In order to capture high-resolution images, it is preferable that the sub-pixels PS be provided in all pixels of the display device. On the other hand, when used in a touch sensor or near-touch sensor, the sub-pixels PS do not require high accuracy compared to when capturing images of fingerprints, etc., so it is sufficient to provide the sub-pixels PS in only some of the pixels of the display device. By making the number of sub-pixels PS in the display device smaller than the number of sub-pixels R, etc., the detection speed can be increased.

[0454] FIG. 19G shows an example of a pixel circuit of a sub-pixel having a light-receiving device, and FIG. 19H shows an example of a pixel circuit of a sub-pixel having a light-emitting device.

[0455] 19G 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.

[0456] The anode of the light-receiving device PD is electrically connected to the wiring V1, and the cathode is electrically connected to one of the source and drain of the transistor M11. The gate of the transistor M11 is electrically connected to the wiring TX, and the other of the source and drain is electrically connected to one electrode of the capacitor C2, one of the source and drain of the transistor M12, and the gate of the transistor M13. The gate of the transistor M12 is electrically connected to the wiring RES, and the other of the source and drain is electrically connected to the wiring V2. The source and drain of the transistor M13 is electrically connected to the wiring V3, and the other of the source and drain is electrically connected to one of the source and drain of the transistor M14. The gate of the transistor M14 is electrically connected to the wiring SE, and the other of the source and drain is electrically connected to the wiring OUT1.

[0457] A constant potential is supplied to the wiring V1, the wiring V2, and the wiring V3. When the light-receiving device PD is driven in a reverse bias, a potential higher 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 an output according to the potential of the node to an external circuit connected to the wiring OUT1.

[0458] 19H includes a light-emitting device EL, transistors M15, M16, and 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.

[0459] 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.

[0460] 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.

[0461] 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.

[0462] 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.

[0463] For example, the off-state current of an OS transistor per 1 μm channel width at room temperature is 1 aA (1×10 -18 A) Below, 1zA(1×10 -21 A) or less, or 1yA (1 x 10 -24 A) or less. Note that the off-state current of a Si transistor per 1 μm of channel width at room temperature is 1 fA (1×10 -15 A) More than 1pA (1×10 -12 Therefore, it can be said that the off-state current of an OS transistor is about 10 orders of magnitude lower than that of a Si transistor.

[0464] 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.

[0465] 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.

[0466] Although the transistors are shown as n-channel transistors in FIGS. 19G and 19H, p-channel transistors can also be used.

[0467] 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.

[0468] 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.

[0469] To increase the emission luminance of the light-emitting device EL included in the pixel circuit, it is necessary to increase the amount of current flowing through the light-emitting device EL. To achieve this, it is necessary to increase the source-drain voltage of the drive transistor included in the pixel circuit. Because OS transistors have a higher source-drain withstand voltage compared to Si transistors, a high voltage can be applied between the source and drain of an OS transistor. Therefore, by using an OS transistor as the drive transistor included in the pixel circuit, it is possible to increase the amount of current flowing through the light-emitting device and increase the emission luminance of the light-emitting device.

[0470] Furthermore, when the transistor operates in the saturation region, OS transistors can reduce the change in source-drain current relative to a change in gate-source voltage compared to Si transistors. Therefore, by using OS transistors as the drive transistors in pixel circuits, the current flowing between the source and drain can be precisely controlled by changing the gate-source voltage, thereby controlling the amount of current flowing through the light-emitting device. This allows for a wider range of gradations in the pixel circuit.

[0471] Furthermore, in terms of the saturation characteristics of the current that flows when the transistor operates in the saturation region, OS transistors can pass a more stable current (saturation current) than Si transistors, even when the source-drain voltage gradually increases. Therefore, by using an OS transistor as a drive transistor, a stable current can be passed through a light-emitting device, for example, even when the current-voltage characteristics of a light-emitting device containing an EL material vary. In other words, when operating in the saturation region, the source-drain current of an OS transistor remains almost unchanged even when the source-drain voltage increases, thereby stabilizing the light-emitting brightness of the light-emitting device.

[0472] As described above, by using an OS transistor for the drive transistor included in the pixel circuit, it is possible to achieve "suppression of black floating," "increase in light emission brightness," "multiple gradations," and "suppression of variation in light-emitting devices."

[0473] Furthermore, the display device of one embodiment of the present invention can vary its refresh rate. For example, the refresh rate can be adjusted (for example, within a range of 0.01 Hz to 240 Hz) depending on the content displayed on the display device, thereby reducing power consumption. Furthermore, driving that reduces the power consumption of the display device by driving it at a reduced refresh rate may be referred to as idling stop (IDS) driving.

[0474] The drive frequency of the touch sensor or near-touch sensor may be changed depending on the refresh rate. For example, if the refresh rate of the display device is 120 Hz, the drive frequency of the touch sensor or near-touch sensor may be configured to be higher than 120 Hz (typically 240 Hz). This configuration enables low power consumption and an increased response speed of the touch sensor or near-touch sensor.

[0475] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0476] (Embodiment 6) In this embodiment, a high-definition display device will be described.

[0477] [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.

[0478] 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.

[0479] Fig. 20A shows an example of the configuration of a display panel. In Fig. 20A, 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.

[0480] The display unit 702L and the display unit 702R shown in FIG. 20A have a square top surface shape.

[0481] The top surface shape of display unit 702L and display unit 702R may also be another regular polygon. FIG. 20B shows an example of a regular hexagon, FIG. 20C shows an example of a regular octagon, FIG. 20D shows an example of a regular decagon, and FIG. 20E 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.

[0482] 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.

[0483] FIG. 20F shows an example in which the top surfaces of display units 702L and 702R are circular.

[0484] Furthermore, the top surface shapes of the display units 702L and 702R may be asymmetrical, and may not be regular polygons.

[0485] FIG. 20G shows an example in which the top surface shapes of display units 702L and 702R are asymmetrical octagons. FIG. 20H 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.

[0486] 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.

[0487] Fig. 20I shows an example in which two circular display units 702 in Fig. 20F are connected together, and Fig. 20J shows an example in which two regular octagonal display units 702 in Fig. 20C are connected together.

[0488] The above is a description of an example of the configuration of the display panel.

[0489] 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.

[0490] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0491] (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.

[0492] 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.

[0493] 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.

[0494] 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.

[0495] <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.

[0496] 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.

[0497] 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.

[0498] 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 the In-Ga-Zn oxide 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.

[0499] <<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.

[0500] Here, the above-mentioned CAAC-OS, nc-OS, and a-like OS will be described in detail.

[0501] [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.

[0502] 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.

[0503] 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.

[0504] 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.

[0505] 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).

[0506] 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.

[0507] 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.

[0508] 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.

[0509] [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 the 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 system, 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.

[0510] [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.

[0511] <<Oxide semiconductor structure>> Next, the above-mentioned CAC-OS will be described in detail, which relates to the material composition.

[0512] [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.

[0513] 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.

[0514] 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.

[0515] 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.

[0516] It should be noted that there are cases where a clear boundary between the first region and the second region cannot be observed.

[0517] 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.

[0518] 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.

[0519] 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.

[0520] 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).

[0521] 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.

[0522] 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.

[0523] Furthermore, a transistor using CAC-OS has high reliability, making it ideal for various semiconductor devices such as display devices.

[0524] 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.

[0525] <Transistors containing oxide semiconductors> Next, a case where the oxide semiconductor is used in a transistor will be described.

[0526] By using the oxide semiconductor for a transistor, a transistor with high field-effect mobility and high reliability can be realized.

[0527] 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 -3Less than 1×10, more preferably 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.

[0528] 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.

[0529] Furthermore, charges trapped in the trap states of an oxide semiconductor take a long time to disappear 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.

[0530] 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.

[0531] <Impurities> Here, the influence of each impurity in an oxide semiconductor will be described.

[0532] 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.

[0533] 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:

[0534] 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 / cm 3 Less than 1×10, more preferably 18 atoms / cm 3 Less than 5 × 10, more preferably 17 atoms / cm 3 Do the following:

[0535] 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.

[0536] When an oxide semiconductor with sufficiently reduced impurities is used for a channel formation region of a transistor, stable electrical characteristics can be obtained.

[0537] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0538] (Embodiment 8) In this embodiment, electronic devices of one embodiment of the present invention will be described with reference to FIGS.

[0539] 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.

[0540] 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.

[0541] 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.

[0542] 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).

[0543] 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.

[0544] 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.

[0545] 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.

[0546] 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).

[0547] 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.

[0548] Electronic device 6500 shown in FIG. 21A is a portable information terminal that can be used as a smartphone.

[0549] 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.

[0550] The display device of one embodiment of the present invention can be applied to the display portion 6502.

[0551] FIG. 21B is a schematic cross-sectional view including the end of the housing 6501 on the microphone 6506 side.

[0552] 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.

[0553] 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).

[0554] 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.

[0555] 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.

[0556] 22A 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.

[0557] The display device of one embodiment of the present invention can be applied to the display portion 7000.

[0558] 22A can be operated using operation switches on the housing 7101 and a separate remote control 7111. Alternatively, a touch sensor may be provided on 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. Using operation keys or a touch panel provided on the remote control 7111, the channel and volume can be controlled, and the video displayed on the display unit 7000 can be operated.

[0559] 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.

[0560] 22B 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.

[0561] The display device of one embodiment of the present invention can be applied to the display portion 7000.

[0562] 22C and 22D show an example of digital signage.

[0563] 22C 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.

[0564] 22D 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.

[0565] 22C and 22D, the display device of one embodiment of the present invention can be applied to the display portion 7000.

[0566] 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.

[0567] 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.

[0568] 22C and 22D , 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.

[0569] 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.

[0570] FIG. 23A is a diagram showing the appearance of the camera 8000 with the viewfinder 8100 attached.

[0571] 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 of the camera 8000 may be integrated together.

[0572] 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.

[0573] 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.

[0574] The finder 8100 includes a housing 8101, a display portion 8102, a button 8103, and the like.

[0575] 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.

[0576] The button 8103 has a function such as a power button.

[0577] 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.

[0578] FIG. 23B is a diagram showing the appearance of the head mounted display 8200.

[0579] 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.

[0580] 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.

[0581] 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.

[0582] The display device of one embodiment of the present invention can be applied to the display portion 8204.

[0583] 23C to 23E 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.

[0584] 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.

[0585] 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. 23E, the pixels are hardly visible to the user. That is, the display portion 8302 allows the user to view a highly realistic image.

[0586] 23F 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, 3D display using parallax can be performed.

[0587] A user can view the display portion 8404 through the lens 8405. The lens 8405 has a focus adjustment mechanism, and its position can be adjusted 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.

[0588] 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.

[0589] 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.

[0590] The electronic device shown in Figures 24A to 24F 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.

[0591] 24A to 24F 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.

[0592] The display device of one embodiment of the present invention can be applied to the display portion 9001 .

[0593] The electronic device shown in FIGS. 24A to 24F will be described in detail below.

[0594] FIG. 24A 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. 24A 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.

[0595] 24B is a perspective view showing a mobile information terminal 9102. The mobile information terminal 9102 has a function of displaying information on three or more sides of the 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 the user holds the mobile information terminal 9102 in a breast pocket of their clothes, the user can check information 9053 displayed in a position that can be observed from above the mobile information terminal 9102. The user can check the display without taking the mobile information terminal 9102 out of their pocket and decide, for example, whether to answer a call.

[0596] FIG. 24C 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.

[0597] 24D to 24F are perspective views showing a foldable mobile information terminal 9201. FIG. 24D shows the mobile information terminal 9201 in an unfolded state, FIG. 24F shows it in a folded state, and FIG. 24E is a perspective view showing a state in the process of changing from one of FIG. 24D and FIG. 24F 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.

[0598] 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.

[0599] 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]

[0600] 100: display device, 101: substrate, 105: insulating layer, 110: light-emitting element, 110B: light-emitting element, 110G: light-emitting element, 110R: light-emitting element, 110S: light-receiving element, 111: pixel electrode, 111B: pixel electrode, 111C: connection electrode, 111G: pixel electrode, 111R: pixel electrode, 111S: pixel electrode, 112: organic layer, 112B: organic layer, 112G: organic layer, 112R: organic layer, 113: common electrode, 114: organic layer, 115: organic layer, 116: organic layer, 12 0: slit, 121: protective layer, 125: insulating layer, 125f: insulating film, 126: resin layer, 130: connecting portion, 131: insulating layer, 132: insulating layer, 135B: layer, 135G: layer, 135R: layer, 135S: layer, 143: resist mask, 144: sacrificial film, 145: sacrificial layer, 146: sacrificial film, 147: sacrificial layer, 151B: FMM, 151G: FMM, 151R: FMM, 151S: FMM, 155: organic layer, 161: conductive layer, 162: conductive layer, 163: resin layer

Claims

1. It has a plurality of pixels arranged in a matrix, At least one of the plurality of pixels is a display device having one or more sub-pixels each having a light-emitting element and a light-receiving element, a first conductive layer having a region in contact with an upper surface of the first insulating layer and functioning as a pixel electrode of the light-emitting element; a second conductive layer having a region in contact with an upper surface of the first insulating layer and functioning as a pixel electrode of the light receiving element; a first organic layer having a region located above the first conductive layer; a second organic layer having a region located above the second conductive layer; a third conductive layer having a region located above the first organic layer and a region located above the second organic layer, and having a function as a common electrode for the light-emitting element and a function as a common electrode for the light-receiving element; a first layer having a region located between the light emitting element and the light receiving element in a plan view and having a region overlapping with the second organic layer; a second layer having a region located between the light-emitting element and the light-receiving element in a plan view and having a region overlapping with the first organic layer; the first organic layer contains a light-emitting organic compound; the second organic layer includes a photoelectric conversion material; the first layer has the same material as the first organic layer; The display device, wherein the second layer has the same material as the second organic layer.

2. It has a plurality of pixels arranged in a matrix, At least one of the plurality of pixels is a display device having one or more sub-pixels each having a light-emitting element and a light-receiving element, a first conductive layer having a region in contact with an upper surface of the first insulating layer and functioning as a pixel electrode of the light-emitting element; a second conductive layer having a region in contact with an upper surface of the first insulating layer and functioning as a pixel electrode of the light receiving element; a first organic layer having a region located above the first conductive layer; a second organic layer having a region located above the second conductive layer; a third organic layer having, in a cross-sectional view, a region located between the first conductive layer and the first organic layer and a region located between the second conductive layer and the second organic layer; a third conductive layer having a region located above the first organic layer and a region located above the second organic layer, and having a function as a common electrode for the light-emitting element and a function as a common electrode for the light-receiving element; a first layer having a region located between the light emitting element and the light receiving element in a plan view and having a region overlapping with the second organic layer; a second layer having a region located between the light-emitting element and the light-receiving element in a plan view and having a region overlapping with the first organic layer; the first organic layer contains a light-emitting organic compound; the second organic layer includes a photoelectric conversion material; the first layer has the same material as the first organic layer; The display device, wherein the second layer has the same material as the second organic layer.

3. It has a plurality of pixels arranged in a matrix, At least one of the plurality of pixels is a display device having one or more sub-pixels each having a light-emitting element and a light-receiving element, a first conductive layer having a region in contact with an upper surface of the first insulating layer and functioning as a pixel electrode of the light-emitting element; a second conductive layer having a region in contact with an upper surface of the first insulating layer and functioning as a pixel electrode of the light receiving element; a first organic layer having a region located above the first conductive layer; a second organic layer having a region located above the second conductive layer; a third conductive layer having a region located above the first organic layer and a region located above the second organic layer, and having a function as a common electrode for the light-emitting element and a function as a common electrode for the light-receiving element; a third organic layer having, in a cross-sectional view, a region located between the first organic layer and the third conductive layer and a region located between the second organic layer and the third conductive layer; a first layer having a region located between the light emitting element and the light receiving element in a plan view and having a region overlapping with the second organic layer; a second layer having a region located between the light-emitting element and the light-receiving element in a plan view and having a region overlapping with the first organic layer; the first organic layer contains a light-emitting organic compound; the second organic layer includes a photoelectric conversion material; the first layer has the same material as the first organic layer; The display device, wherein the second layer has the same material as the second organic layer.

4. It has a plurality of pixels arranged in a matrix, At least one of the plurality of pixels is a display device having one or more sub-pixels each having a light-emitting element and a light-receiving element, a first conductive layer having a region in contact with an upper surface of the first insulating layer and functioning as a pixel electrode of the light-emitting element; a second conductive layer having a region in contact with an upper surface of the first insulating layer and functioning as a pixel electrode of the light receiving element; a first organic layer having a region located above the first conductive layer; a second organic layer having a region located above the second conductive layer; a third organic layer having, in a cross-sectional view, a region located between the first conductive layer and the first organic layer and a region located between the second conductive layer and the second organic layer; a third conductive layer having a region located above the first organic layer and a region located above the second organic layer, and having a function as a common electrode for the light-emitting element and a function as a common electrode for the light-receiving element; a fourth organic layer having, in a cross-sectional view, a region located between the first organic layer and the third conductive layer and a region located between the second organic layer and the third conductive layer; a first layer having a region located between the light emitting element and the light receiving element in a plan view and having a region overlapping with the second organic layer; a second layer having a region located between the light-emitting element and the light-receiving element in a plan view and having a region overlapping with the first organic layer; the first organic layer contains a light-emitting organic compound; the second organic layer includes a photoelectric conversion material; the first layer has the same material as the first organic layer; The display device, wherein the second layer has the same material as the second organic layer.

5. In any one of claims 1 to 4, a second insulating layer having a region located between the light emitting element and the light receiving element in a plan view; a second insulating layer having a region in contact with a side surface of the first organic layer, a region in contact with a side surface of the second organic layer, a region in contact with a side surface of the first layer, and a region in contact with a side surface of the second layer.

Images