Electronic device

Abstract

Provided is an electronic device having a line-of-sight tracking function. The electronic device has a display device and an optical system. The display device has a first light-emitting element, a second light-emitting element, a sensor unit, and a drive circuit unit. The sensor unit has a light receiving element. The first light-emitting element has a function of emitting infrared light or visible light. The second light-emitting element has a function of emitting light having a different color from the color of light emitted by the first light-emitting element. In the case in which the first light-emitting element emits infrared light, the light receiving element has a function of detecting the infrared light emitted from the first light-emitting element and reflected by an eyeball of a user. In addition, in the case in which the first light-emitting element emits visible light, the light receiving element has a function of detecting the visible light emitted from the first light-emitting element and reflected by an eyeball of a user. The first light-emitting element and the second light-emitting element are disposed in the same layer. The layer in which the first light-emitting element and the second light-emitting element are positioned overlaps with the sensor unit.

Description

electronic equipment

[0001] One embodiment of the present invention relates to a display device or an electronic device.

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

[0003] In recent years, devices for virtual reality (VR) or augmented reality (AR) have been attracting attention. Furthermore, devices for VR or AR equipped with an eye tracking function have been developed. Devices for VR or AR equipped with an eye tracking function can be applied to, for example, consumer behavior analysis, image processing, avatar creation, gaze-based operation, and the like.

[0004] For example, Patent Document 1 discloses a head-mounted display that performs gaze tracking using an image of light from a light source reflected by the cornea.

[0005] Special table 2019-512726 publication

[0006] Conventional VR or AR devices are bulky and consume a lot of power because they include displays, light sources, cameras, and many other sensors.

[0007] In view of the above problems, an object of one embodiment of the present invention is to provide an electronic device having an eye-tracking function and a reduced housing volume. Another object of one embodiment of the present invention is to provide an electronic device having an eye-tracking function and consuming low power. Another object of one embodiment of the present invention is to provide an electronic device having an eye-tracking function that is miniaturized or lightweight. Another object of one embodiment of the present invention is to provide an electronic device having an eye-tracking function and incorporating a high-resolution display device. Another object of one embodiment of the present invention is to provide an electronic device having an eye-tracking function and incorporating a highly reliable display device. Another object of one embodiment of the present invention is to provide an electronic device having a novel structure.

[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.

[0009] One embodiment of the present invention is an electronic device having an eye tracking function and including a display device and an optical system. The display device includes a first light-emitting element, a second light-emitting element, a sensor unit, and a driver circuit unit. The sensor unit has a light-receiving element, the first light-emitting element has a function of emitting infrared light, the second light-emitting element has a function of emitting visible light, and the light-receiving element has a function of detecting infrared light emitted by the first light-emitting element and reflected by a user's eyeball. The first light-emitting element and the second light-emitting element are arranged in the same layer, and the layer where the first light-emitting element and the second light-emitting element are located overlaps with the sensor unit.

[0010] In the above electronic device, it is preferable that the display device further includes a first substrate and a second substrate, the first substrate being arranged between the first light-emitting element and the second light-emitting element and the sensor portion, the second substrate being overlapped with the first substrate via the first light-emitting element and the second light-emitting element, and the first substrate being translucent to at least infrared light, and the second substrate being translucent to visible light and infrared light.

[0011] In any one of the electronic devices described above, the light receiving element is preferably formed on a silicon substrate.

[0012] Another aspect of the present invention is an electronic device having an eye tracking function and including a display device and an optical system, wherein the display device has a first light-emitting element, a second light-emitting element, a sensor unit, and a driver circuit unit, the sensor unit has a light-receiving element, the first light-emitting element has a function of emitting infrared light, the second light-emitting element has a function of emitting visible light, the light-receiving element has a function of detecting infrared light emitted by the first light-emitting element and reflected by a user's eyeball, and the first light-emitting element, the second light-emitting element, and the sensor unit are arranged parallel to and in line with top surfaces of pixel electrodes of the first light-emitting element and the second light-emitting element.

[0013] In the above electronic device, it is preferable that the display device further includes a first substrate and a second substrate, the first substrate overlapping the second substrate via the first light-emitting element, the second light-emitting element, and the sensor portion, and the second substrate being translucent to visible light and infrared light.

[0014] In any one of the electronic devices described above, the first light-emitting element is preferably arranged outside the display area, or the first light-emitting element is preferably arranged inside the display area.

[0015] In any one of the electronic devices, the sensor unit is preferably arranged within the display area, or the sensor unit is preferably arranged outside the display area.

[0016] In any one of the electronic devices, the display device preferably further includes an image processing unit, and performs gaze tracking using the first light-emitting element, the sensor unit, and the image processing unit. The image processing unit preferably includes an arithmetic circuit having a function of performing product-sum operations. The arithmetic circuit preferably includes a transistor having a channel formation region containing a metal oxide.

[0017] In any one of the electronic devices, the second light-emitting element preferably has a function of emitting red, green, or blue light.

[0018] In any one of the above electronic devices, a light-emitting layer included in the first light-emitting element and a light-emitting layer included in the second light-emitting element preferably contain a light-emitting organic compound.

[0019] Another embodiment of the present invention is an electronic device having an eye tracking function. The electronic device includes a display device and an optical system. The display device includes a first light-emitting element, a second light-emitting element, an organic photodiode, and a driver circuit unit. The first light-emitting element and the second light-emitting element emit visible light. The organic photodiode detects the visible light emitted by the first light-emitting element and reflected by a user's eyeball. The first light-emitting element is disposed outside a display area when viewed from above. The second light-emitting element is disposed inside the display area when viewed from above. The first light-emitting element, the second light-emitting element, and the organic photodiode are disposed in the same layer.

[0020] In the above electronic device, it is preferable that the display device further includes a first substrate and a second substrate, the first light-emitting element, the second light-emitting element, and the organic photodiode are arranged between the first substrate and the second substrate, the first light-emitting element, the second light-emitting element, and the organic photodiode are arranged parallel to the top surface of the first substrate, and the second substrate is translucent to visible light.

[0021] In the electronic device, the organic photodiode is preferably disposed inside the display area when viewed from above, or is preferably disposed outside the display area when viewed from above.

[0022] In the electronic device, the display device preferably further includes an image processing unit, and performs gaze tracking using the first light-emitting element, the organic photodiode, and the image processing unit. The image processing unit preferably includes an arithmetic circuit having a function of performing a product-sum operation. The arithmetic circuit preferably includes a transistor having a channel formation region containing a metal oxide.

[0023] In the electronic device, the first light-emitting element preferably has a function of emitting red light.

[0024] In the electronic device, it is preferable that the light-emitting layer of the first light-emitting element and the light-emitting layer of the second light-emitting element contain a light-emitting organic compound.

[0025] One embodiment of the present invention can provide an electronic device with an eye-tracking function and a reduced housing volume. Another embodiment of the present invention can provide an electronic device with an eye-tracking function that consumes low power. Another embodiment of the present invention can provide an electronic device with an eye-tracking function that is small or lightweight. Another embodiment of the present invention can provide an electronic device with an eye-tracking function that is equipped with a high-resolution display device. Another embodiment of the present invention can provide an electronic device with an eye-tracking function that is equipped with a highly reliable display device. Another embodiment of the present invention can provide an electronic device with a novel structure.

[0026] 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.

[0027] FIGS. 1A and 1B are diagrams showing an example of the configuration of an electronic device. FIGS. 2A and 2B are diagrams showing an example of the configuration of a display device. FIGS. 3A and 3B are diagrams showing an example of the configuration of a display device. FIG. 4 is a diagram showing an example of the configuration of an electronic device. FIGS. 5A and 5B are diagrams showing an example of the configuration of a display device. FIGS. 6A and 6B are diagrams showing an example of the configuration of a display device. FIG. 7 is a flowchart showing an example of the operation of an electronic device. FIG. 8 is a diagram showing an example of the configuration of an electronic device. FIGS. 9A and 9B are diagrams showing an example of the configuration of a display device. FIG. 10 is a diagram showing an example of the configuration of an electronic device. FIGS. 11A and 11B are diagrams showing an example of the configuration of a display device. FIGS. 12A to 12C are diagrams showing an example of the configuration of an electronic device. FIGS. 13A to 13E are diagrams showing an example of an electronic device. FIGS. 14A and 14B are diagrams showing an example of the configuration of an electronic device. FIG. 15 is a diagram explaining an example of the configuration of a neural network arithmetic circuit. FIG. 16 is a diagram explaining an example of the configuration of a neural network arithmetic circuit. FIG. 17 is a diagram explaining an example of the configuration of a neural network arithmetic circuit. FIGS. 18A and 18B are diagrams illustrating an example of the configuration of a display device. FIGS. 19A and 19B are diagrams illustrating an example of the configuration of a display device. FIGS. 20A to 20E are diagrams illustrating an example of the configuration of a display device. FIGS. 21A and 21B are diagrams illustrating an example of the configuration of a display device. FIGS. 22A and 22B are diagrams illustrating an example of the configuration of a display device. FIGS. 23A and 23B are diagrams illustrating an example of the configuration of a display device. FIGS. 24A and 24B are diagrams illustrating an example of the configuration of a display device. FIGS. 25A and 25B are diagrams illustrating an example of the configuration of a display device. FIGS. 26A to 26D are diagrams illustrating an example of the configuration of a light-emitting element. FIG. 27 is a diagram illustrating an example of the configuration of a display device. FIGS. 28A and 28B are diagrams illustrating an example of the configuration of a display device. FIGS. 29A to 29G are diagrams illustrating an example of the configuration of a display device. FIG. 30 is a diagram illustrating an example of the configuration of a display device.

[0028] 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 description of the following embodiments.

[0029] 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.

[0030] 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.

[0031] In this specification, ordinal numbers such as "first" and "second" are used to avoid confusion of components and do not limit the number.

[0032] 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."

[0033] Furthermore, in this specification, "parallel" refers to a state in which two straight lines are arranged at an angle of -10 degrees or more and 10 degrees or less. Therefore, it also includes cases in which the angle is -5 degrees or more and 5 degrees or less. Furthermore, "substantially parallel" refers to a state in which two straight lines are arranged at an angle of -30 degrees or more and 30 degrees or less. Furthermore, "perpendicular" refers to a state in which two straight lines are arranged at an angle of 80 degrees or more and 100 degrees or less. Therefore, it also includes cases in which the angle is 85 degrees or more and 95 degrees or less. Furthermore, "substantially perpendicular" refers to a state in which two straight lines are arranged at an angle of 60 degrees or more and 120 degrees or less.

[0034] 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.

[0035] In this specification and the like, a display panel, which is one aspect of a display device, has a function of displaying (outputting) an image or the like on a display surface, and therefore the display panel is one aspect of an output device.

[0036] Furthermore, in this specification, a display panel having a connector such as an FPC (Flexible Printed Circuit) or a TCP (Tape Carrier Package) attached to its substrate, or a substrate having an IC mounted thereon using a COG (Chip On Glass) method or the like, may be referred to as a display panel module, a display module, or simply a display panel.

[0037] Embodiment 1 In this embodiment, configuration examples and operation examples of an electronic device of one embodiment of the present invention will be described.

[0038] One embodiment of the present invention is an electronic device equipped with a display device including a light-emitting element (which can also be referred to as a light-emitting device) and a light-receiving element (which can also be referred to as a light-receiving device or a photoelectric conversion device). The display device has two or more light-emitting elements that emit light of different colors, and at least one light-emitting element that emits infrared light. Note that infrared light is invisible light, but the "color" described in this specification and the like may also include infrared light. Each light-emitting element has a pair of electrodes and an EL layer therebetween. The light-emitting element is preferably an organic EL element (organic electroluminescent element). Two or more light-emitting elements that emit different colors each have an EL layer containing a different material. For example, by having four types of light-emitting elements that emit red (R), green (G), or blue (B) visible light and infrared light (IR), an electronic device equipped with a full-color display device with an eye-tracking function can be realized.

[0039] One embodiment of the present invention includes a light-emitting element that emits infrared light and a light-receiving element that detects the infrared light. This allows for an eye-tracking function using the infrared light. That is, the infrared light emitted from the light-emitting element is irradiated onto a user's eyeball, and the infrared light reflected from the user's eyeball is detected by the light-receiving element, thereby enabling eye-tracking of the user.

[0040] In this case, one embodiment of the present invention uses invisible infrared light to perform gaze tracking without interfering with the display of an electronic device. Since the user does not sense unnecessary light, the user can use the electronic device without stress.

[0041] Furthermore, by providing an infrared light emitting element in the same location as the display light emitting elements (RGB, etc.), there is no need to provide an infrared light emitting device for eye tracking, which allows for space saving in electronic devices, making them smaller and lighter, or allowing for larger batteries.

[0042] Another embodiment of the present invention is an electronic device equipped with a display device having a light-emitting element and a light-receiving element. The display device has two or more light-emitting elements that emit light of different colors. The two or more light-emitting elements that emit different colors have EL layers containing different materials. For example, by having three types of light-emitting elements that emit red (R), green (G), or blue (B) visible light, respectively, an electronic device equipped with a full-color display device with an eye-tracking function can be realized.

[0043] Another embodiment of the present invention includes a light-emitting element that emits visible light and a light-receiving element that detects visible light. This allows for a gaze tracking function using visible light. That is, the visible light emitted from the light-emitting element is irradiated onto a user's eyeball, and the visible light reflected from the user's eyeball is detected by the light-receiving element, thereby enabling gaze tracking of the user.

[0044] In this case, another embodiment of the present invention is to perform gaze tracking using visible light emitted from a light-emitting element provided outside the display area, thereby enabling gaze tracking without interfering with the display of the electronic device.

[0045] Furthermore, by providing the visible light emitting element used for gaze tracking in the same way as the display light emitting element (RGB, etc.), there is no need to provide a visible light emitting device for gaze tracking, which can save space in electronic devices, allowing for smaller and lighter electronic devices or larger batteries.

[0046] Furthermore, by using an element (sometimes referred to as an MML structure) formed without using a metal mask or an FMM (fine metal mask, high-definition metal mask), it is possible to provide an electronic device equipped with a display device that combines an eye-tracking function and high definition. Details of the MML structure will be described in embodiment 4.

[0047] First, a configuration example and an operation example of an electronic device having an eye-tracking function using infrared light will be described. Note that the following description may also include a configuration example and an operation example of an electronic device having an eye-tracking function using visible light.

[0048] [Configuration Example 1 of Electronic Device] The configuration of an electronic device according to one embodiment of the present invention will be described with reference to the block diagrams shown in Figures 1A and 1B. Electronic device 150 shown in Figure 1A includes display devices 100 (100_R and 100_L), optical systems 151 (151_R and 151_L), a motion detection unit 153, audio 154, a camera 155, a control unit 156, a communication unit 157, and a battery 158. Display device 100, motion detection unit 153, audio 154, camera 155, control unit 156, and communication unit 157 transmit and receive various signals to and from each other via bus wiring BW.

[0049] As shown in FIG. 1B , the display device 100 includes light-emitting elements 110R, 110G, and 110B as display elements, a light-emitting element 110IR as a light source, a sensor unit 104, a drive circuit unit 120, an image processing unit 121, and a frame memory 122. The drive circuit unit 120 includes a gate driver circuit and a source driver circuit. One or more gate driver circuits and one or more source driver circuits may be provided. In the example shown in FIG. 1A , two display devices 100 are provided, one for the right eye and one for the left eye, but the number of display devices may be one or three or more.

[0050] In the following, when describing matters common to the light-emitting element 110R, the light-emitting element 110G, the light-emitting element 110B, and the light-emitting element 110IR, as well as the light-emitting element 110LS described later, the symbols attached to the reference numerals may be omitted and the light-emitting element may be described as the light-emitting element 110. Alternatively, when the light-emitting element 110 is described, it may refer to one or more of the light-emitting element 110R, the light-emitting element 110G, the light-emitting element 110B, the light-emitting element 110IR, and the light-emitting element 110LS.

[0051] The optical system 151 includes, for example, a lens. Furthermore, if necessary, it may include a reflector, a half mirror, a waveguide, etc. In the example shown in FIG. 1A, two optical systems 151 are provided, one for the right eye and one for the left eye, but the number of optical systems may be one, or three or more.

[0052] The audio 154 includes, for example, one or more of a microphone and a speaker. The motion detection unit 153 includes an inertial sensor and has the function of detecting the user's body movements. Note that the inertial sensor here refers to a sensor that detects the acceleration and angular velocity of an object. The control unit 156 includes a CPU, a GPU, and a memory. The communication unit 157 performs wireless communication and can exchange data with other terminals or servers on a network. Note that the control unit 156 and communication unit 157, enclosed by dotted lines in FIG. 1A, may be provided separately from the electronic device 150. In this case, the bulk of the electronic device can be reduced.

[0053] The image data generated by the control unit 156 is sent to the display device 100 via the bus wiring BW. After being stored in the frame memory 122, the image data passes through a source driver included in the drive circuit unit 120 and is displayed by the light-emitting elements 110R, 110G, and 110B.

[0054] The data (analog data) acquired by the sensor unit 104 is converted into digital data by the image processing unit 121 and sent to the control unit 156. For example, the sensor unit 104 acquires an image of the user's eyes, and the image processing unit 121 identifies the position of the user's gaze from the acquired image. The control unit 156 receives the gaze position data from the image processing unit 121 and reflects it in the image data seen by the user.

[0055] The image processing unit 121 has a function of performing image analysis. By performing image analysis, the position of the user's gaze can be identified from the image of the user's eye acquired by the sensor unit 104. In other words, gaze tracking can be performed using the image processing unit 121. For the image analysis, a neural network, an arithmetic circuit having a function of performing product-sum operations, or the like can be used. In other words, the image processing unit 121 includes at least one of a processing device capable of executing a program including a neural network, an arithmetic circuit having a function of performing product-sum operations, or the like.

[0056] For the image analysis, it is particularly preferable to use an arithmetic circuit having a function of performing a product-sum operation. By using such an arithmetic circuit, image analysis can be performed with low power. Therefore, the power consumption of a display device according to one embodiment of the present invention or an electronic device equipped with the display device can be reduced. Details of the arithmetic circuit having a function of performing a product-sum operation will be described in Embodiment 3.

[0057] A neural network may be used for the image analysis. It is particularly preferable to use deep learning as the neural network. As the deep learning, it is preferable to use, for example, a convolutional neural network (CNN), a recurrent neural network (RNN), an autoencoder (AE), a variational autoencoder (VAE), a random forest, a support vector machine, gradient boosting, or a generative adversarial network (GAN).

[0058] Below, the structure of a display device included in an electronic device of one embodiment of the present invention will be described with reference to FIGS. 2A to 6B. FIG.

[0059] [Configuration Example 1 of Display Device] Schematic diagrams of the display device 100 shown in FIG. 1B included in an electronic device according to one embodiment of the present invention are shown in FIGS. 2A and 2B , 3A and 3B , 5A and 5B , and 6A and 6B . The display device 100 shown in FIG. 2A includes a substrate 101, a substrate 102, a light-emitting element 110, and a sensor portion 104. The light-emitting element 110 includes a light-emitting element serving as a display element and a light-emitting element serving as a light source, and is located in a layer 106. The sensor portion 104 is provided on a support plate 103, the substrate 101 is provided on the sensor portion 104, the light-emitting element 110 is provided on the substrate 101, the substrate 102 is provided on the light-emitting element 110, and a protective member 105 is provided on the substrate 102. The display device 100 shown in FIG. 2A has a configuration in which a light-emitting element 110IR serving as a light source is provided outside a display region 109. Details of each component will be described later.

[0060] The light-emitting element 110 may be configured to include, for example, a light-emitting element 110R that emits red light, a light-emitting element 110G that emits green light, a light-emitting element 110B that emits blue light, and a light-emitting element 110IR that emits infrared light. In this case, the light-emitting elements 110R, 110G, and 110B function as display elements, and the light-emitting element 110IR functions as a light source. The number of light-emitting elements 110IR is not particularly limited and may be one or more. The light-emitting element 110 is disposed in a region sandwiched between the substrate 101 and the substrate 102. The substrate 101 is disposed between the support plate 103 and the light-emitting element 110, and the substrate 102 is disposed between the light-emitting element 110 and the protective member 105.

[0061] The light emitted by the light emitting element 110IR preferably includes infrared light, and more preferably includes near-infrared light. For example, near-infrared light having one or more peaks in the wavelength range of 700 nm or more and 2500 nm or less can be suitably used. Here, the peak is, for example, a maximum value or a local maximum value. Note that infrared light is classified into near-infrared light, mid-infrared light, and far-infrared light depending on the wavelength. In other words, near-infrared light is included in infrared light.

[0062] 2A includes a light receiving element having a function of detecting infrared light. The light receiving element preferably has optical sensitivity corresponding to infrared light, preferably near-infrared light, emitted by the light emitting element 110IR.

[0063] As shown in FIG. 2A , an image is displayed by the light emitted by light-emitting elements 110R, 110G, and 110B. Furthermore, infrared light emitted from light-emitting element 110IR is reflected by the user's eyeball 108, and the reflected light is detected by the light-receiving element of sensor unit 104, thereby performing gaze tracking. Therefore, substrate 102 and protective member 105 must transmit both visible light from light-emitting elements 110R, 110G, and 110B, and infrared light reflected by light-emitting element 110IR and eyeball 108. Therefore, substrate 102 and protective member 105 are preferably translucent for visible light and infrared light. Furthermore, infrared light reflected by eyeball 108 must pass through substrate 101. Therefore, substrate 101 is preferably translucent for at least infrared light.

[0064] The substrates 101 and 102 can each be made of an insulator such as glass, quartz, ceramic, sapphire, or stabilized zirconia (e.g., yttria-stabilized zirconia); a resin such as an insulating resin or a conductive resin; a semiconductor such as silicon, germanium, silicon carbide, silicon germanium, gallium arsenide, indium phosphide, or zinc oxide; a metal; or an alloy. The substrate on the side from which light from the light-emitting element 110 is extracted is made of a material that transmits the light. Using a flexible material for the substrates 101 and 102 can increase the flexibility of the display device 100 and enable it to be lightweight and thin. A polarizing plate may be used as the substrate 101 or 102.

[0065] Substrates 101 and 102 may each 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 101 and 102 may be made of glass having a thickness sufficient to provide flexibility.

[0066] A display device according to one embodiment of the present invention may have the structure shown in Fig. 2B . The display device 100 shown in Fig. 2B differs from the display device 100 shown in Fig. 2A in that a light-emitting element 110IR serving as a light source is provided in the display region 109. The other configurations are the same as those of the display device 100 shown in Fig. 2A , and therefore the above description of Fig. 2A can be referred to for details.

[0067] As described above, in the display device 100 shown in FIGS. 2A and 2B , the layer 106 in which the light-emitting elements 110, including the light-emitting element 110IR, are located overlaps the sensor unit 104. A common electrode may be provided in the layer 106 in which the light-emitting elements 110 are located, shared by each light-emitting element 110. Therefore, light can be irradiated onto the eyeball 108 and light reflected from the eyeball 108 can be received without using a complex optical system. Furthermore, the distance between the light-emitting element 110IR and the light-receiving element of the sensor unit 104 is relatively small. Therefore, the detection sensitivity of light reflected from the eyeball 108 can be increased. Since the optical system configuration can be simplified, the display device can be miniaturized. Note that a portion of the light-emitting element 110IR may or may not overlap with the sensor unit 104.

[0068] Note that one embodiment of the present invention is not limited thereto. As shown in FIGS. 3A and 3B , the sensor portion 104 may be provided together with the light-emitting element 110 between the substrate 101 and the substrate 102. In other words, the light-emitting element 110 and the sensor portion 104 may be arranged parallel to the top surface of the substrate 101. The sensor portion 104 may be located in the layer 106 where the light-emitting element 110 is located. Specifically, the display device 100 shown in FIG. 3A differs from the display device 100 shown in FIG. 2A in that the sensor portion 104 and the light-emitting element 110 are provided between the substrate 101 and the substrate 102. The display device 100 shown in FIG. 3B differs from the display device 100 shown in FIG. 2B in that the sensor portion 104 and the light-emitting element 110 are provided between the substrate 101 and the substrate 102. In the display device 100 shown in each of Figures 3A and 3B, the sensor portion 104 is provided on the substrate 101, so the substrate 101 may have low translucency to infrared light or may not be translucent to infrared light.

[0069] 3A and 3B, the light-emitting element 110 and the sensor portion 104 are disposed in parallel with the upper surface of the pixel electrode of the light-emitting element 110.

[0070] 2A and 3A, the light-emitting element 110IR serving as a light source is provided outside the display area 109. In this case, as shown in FIG. 4, it is preferable to design the optical system 151 provided between the display device 100 and the eyeball 108 so that infrared light emitted from the light-emitting element 110IR is irradiated onto the user's eyeball. With this configuration, the infrared light emitted from the light-emitting element 110IR is reflected by the user's eyeball 108, and the reflected light is detected by the light-receiving element of the sensor unit 104, thereby enabling gaze tracking.

[0071] Although the above describes a configuration in which the sensor unit 104 is provided within the display region 109, the present invention is not limited to this, and the sensor unit 104 may be provided outside the display region 109. Specifically, the display device 100 shown in FIG. 5A differs from the display device 100 shown in FIG. 2A in that the sensor unit 104 is provided outside the display region 109 together with the light-emitting element 110IR. The display device 100 shown in FIG. 5B differs from the display device 100 shown in FIG. 2B in that the sensor unit 104 is provided outside the display region 109 together with the light-emitting element 110IR. The display device 100 shown in FIG. 6A differs from the display device 100 shown in FIG. 3A in that the sensor unit 104 is provided outside the display region 109 together with the light-emitting element 110IR. The display device 100 shown in FIG. 6B differs from the display device 100 shown in FIG. 3B in that the sensor unit 104 is provided outside the display region 109.

[0072] 2B, 3B, 5B, and 6B, a pixel may be formed using four types of light-emitting elements: a light-emitting element 110R that emits red light, a light-emitting element 110G that emits green light, a light-emitting element 110B that emits blue light, and a light-emitting element 110IR that emits infrared light. However, the present invention is not limited to this. For example, a pixel may be formed using three types of light-emitting elements: the light-emitting element 110R, the light-emitting element 110G, and the light-emitting element 110B, with the light-emitting element 110R emitting light that has peaks at both red and infrared wavelengths.

[0073] In addition, although the above describes a configuration in which a pixel is formed using three types of light-emitting elements, namely, the light-emitting element 110R that emits red (R), the light-emitting element 110G that emits green (G), and the light-emitting element 110B that emits blue (B), the present invention is not limited to this. For example, a pixel may be formed using a light-emitting element that emits yellow (Y) or a light-emitting element that emits orange (O), or a pixel may be formed using a light-emitting element having a light-emitting substance that emits light containing spectral components of two or more colors selected from R, G, and B.

[0074] In addition, in the display devices 100 shown in each of FIGS. 3A, 3B, 6A, and 6B, there are cases where the support plate 103 does not need to be provided.

[0075] 2A, 2B, 5A, and 5B, a substrate may be provided instead of the support plate 103, and an insulating layer may be provided instead of the substrate 101. In this case, the sensor portion 104 may be provided on the substrate, or the sensor portion 104 may be formed using the substrate. Alternatively, an insulating layer may be provided on the sensor portion 104, and the light-emitting element 110 may be provided on the insulating layer. The insulating layer preferably has a light-transmitting property to at least infrared light.

[0076] In addition, in the display devices 100 shown in each of FIGS. 2A, 2B, 3A, 3B, 5A, 5B, 6A, and 6B, there are cases where the protective member 105 does not need to be provided.

[0077] [Operation Example 1 of Electronic Device] An operation example of an electronic device according to one aspect of the present invention will be described below with reference to the flowchart shown in FIG. 7 . The flowchart shown in FIG. 7 includes steps 210 to 213. First, in step 210, a light-emitting element 110IR that emits infrared light as a light source is used to illuminate the user's eyeball 108. Next, in step 211, the light reflected from the eyeball 108 is captured by the light-receiving element of the sensor unit 104. In step 212, the image captured by the light-receiving element is processed to determine the user's gaze direction. Then, in step 213, the displayed image is updated to match the user's gaze direction based on the user's gaze direction. By increasing the resolution only in the area where the user's gaze is directed, the load on the GPU can be reduced.

[0078] By using the present invention, it is possible to track the user's gaze. By tracking the user's gaze, it is possible to understand, for example, what the user is paying attention to, and analyze the user's behavior. It is also possible to make an avatar reproduce the user's eye movements. It is also possible to perform operations or menu selections using gaze.

[0079] The above is a description of an example of the configuration and operation of an electronic device having an eye tracking function using infrared light.

[0080] Next, a configuration example and an operation example of an electronic device with an eye-tracking function using visible light will be described. Hereinafter, differences from an electronic device with an eye-tracking function using infrared light will be mainly described, and overlapping parts will be omitted.

[0081] [Configuration Example 2 of Electronic Device] The configuration of an electronic device according to another embodiment of the present invention will be described with reference to the block diagram shown in Fig. 8. The electronic device with an eye-gaze tracking function using visible light has the same configuration as the electronic device with an eye-gaze tracking function using infrared light (electronic device 150 shown in Fig. 1A). That is, the electronic device includes display devices 100 (100_R and 100_L), optical systems 151 (151_R and 151_L), a motion detection unit 153, audio 154, a camera 155, a control unit 156, a communication unit 157, and a battery 158.

[0082] 1B in that it has a light-emitting element 110LS instead of the light-emitting element 110IR. As shown in FIG. 8, the display device 100 of the electronic device has light-emitting elements 110R, 110G, and 110B as display elements, light-emitting element 110LS as a light source, a sensor unit 104, a drive circuit unit 120, an image processing unit 121, and a frame memory 122.

[0083] Below, a structure of a display device mounted on an electronic device according to another embodiment of the present invention will be described with reference to FIGS. 9A to 11B. FIG.

[0084] [Configuration Example 2 of Display Device] Schematic diagrams of the display device 100 shown in FIG. 8 included in an electronic device according to another embodiment of the present invention are shown in FIGS. 9A , 9B , 11A , and 11B . The display device 100 shown in FIG. 9A differs from the display device 100 shown in FIG. 2A in that it includes a light-emitting element 110LS instead of the light-emitting element 110IR. Hereinafter, differences from the display device 100 shown in FIG. 2A will be mainly described, and descriptions of overlapping parts may be omitted. The display device 100 shown in FIG. 9A has a configuration in which the light-emitting element 110LS serving as a light source is provided outside the display region 109.

[0085] The light emitting element 110LS functions as a light source. The number of light emitting elements 110LS is not particularly limited, and may be one or more. The light emitting element 110LS is disposed in a region sandwiched between the substrate 101 and the substrate 102.

[0086] The light emitted by the light-emitting element 110LS preferably includes visible light. For example, the light-emitting element 110LS is preferably an element that emits monochromatic light whose emission spectrum has one peak in the visible light region, and more preferably an element that emits monochromatic light whose emission spectrum has a peak in the red wavelength region. Furthermore, the light-emitting element 110LS is preferably a light-emitting element having the same configuration as the light-emitting element 110R, the light-emitting element 110G, or the light-emitting element 110B. This allows the light-emitting element 110LS to be formed without increasing the number of fabrication steps. The light-emitting element 110LS may be an element that emits light whose emission spectrum has two or more peaks in the visible light region, or an element that emits light whose emission spectrum also has peaks in regions other than visible light (e.g., infrared light or ultraviolet light).

[0087] 9A includes a light receiving element that has a function of detecting visible light. The light receiving element preferably has optical sensitivity corresponding to the visible light emitted by the light emitting element 110LS.

[0088] 9A , an image is displayed by light emitted by light-emitting elements 110R, 110G, and 110B. Visible light emitted from light-emitting element 110LS is reflected by the user's eyeball 108, and the reflected light is detected by the light-receiving element of sensor unit 104, thereby performing gaze tracking. Therefore, substrate 102 and protective member 105 must transmit visible light emitted by light-emitting elements 110R, 110G, 110B, and 110LS. Furthermore, substrate 101, substrate 102, and protective member 105 must transmit visible light reflected by eyeball 108. Therefore, substrate 101, substrate 102, and protective member 105 are preferably translucent to visible light.

[0089] As described above, in the display device 100 shown in FIG. 9A , the layer 106 in which the light-emitting elements 110 including the light-emitting element 110LS are located overlaps the sensor unit 104. A common electrode may be provided in the layer 106 in which the light-emitting elements 110 are located, which is shared by each light-emitting element 110. Therefore, light can be irradiated onto the eyeball 108 and light reflected from the eyeball 108 can be received without using a complex optical system. Furthermore, the distance between the light-emitting element 110LS and the light-receiving element of the sensor unit 104 is relatively small. Therefore, the detection sensitivity of light reflected from the eyeball 108 can be improved. Since the optical system configuration can be simplified, the display device can be miniaturized. Note that a portion of the light-emitting element 110LS may or may not overlap with the sensor unit 104.

[0090] Note that another embodiment of the present invention is not limited thereto. As shown in FIG. 9B , the sensor portion 104 may be provided together with the light-emitting element 110 between the substrate 101 and the substrate 102. In other words, the light-emitting element 110 and the sensor portion 104 may be arranged parallel to the top surface of the substrate 101. The sensor portion 104 may be located in the layer 106 where the light-emitting element 110 is located. Specifically, the display device 100 shown in FIG. 9B differs from the display device 100 shown in FIG. 9A in that the sensor portion 104 and the light-emitting element 110 are provided between the substrate 101 and the substrate 102. In the display device 100 shown in FIG. 9B , the sensor portion 104 is provided over the substrate 101. Therefore, the substrate 101 may have low light-transmitting properties or may not be light-transmitting properties for visible light.

[0091] 9A and 9B, the light-emitting element 110LS serving as a light source is provided outside the display region 109. In this case, as shown in Fig. 10, it is preferable to design the optical system 151 provided between the display device 100 and the eyeball 108 so that visible light emitted from the light-emitting element 110LS is irradiated onto the user's eyeball. With this configuration, the visible light emitted from the light-emitting element 110LS is reflected by the user's eyeball 108, and the reflected light is detected by the light-receiving element of the sensor unit 104, thereby enabling gaze tracking.

[0092] Although the above describes a configuration in which the sensor unit 104 is provided within the display region 109, the present invention is not limited to this, and the sensor unit 104 may be provided outside the display region 109. Specifically, the display device 100 shown in Fig. 11A differs from the display device 100 shown in Fig. 9A in that the sensor unit 104 is provided outside the display region 109 together with the light-emitting element 110LS. The display device 100 shown in Fig. 11B differs from the display device 100 shown in Fig. 9B in that the sensor unit 104 is provided outside the display region 109 together with the light-emitting element 110LS.

[0093] In addition, although the above describes a configuration in which a pixel is formed using three types of light-emitting elements, namely, the light-emitting element 110R that emits red (R), the light-emitting element 110G that emits green (G), and the light-emitting element 110B that emits blue (B), the present invention is not limited to this. For example, a pixel may be formed using a light-emitting element that emits yellow (Y) or a light-emitting element that emits orange (O), or a pixel may be formed using a light-emitting element having a light-emitting substance that emits light containing spectral components of two or more colors selected from R, G, and B.

[0094] In the display devices 100 shown in FIGS. 9B and 11B, the support plate 103 may not be provided in some cases.

[0095] 9A and 11A, a substrate may be provided instead of the support plate 103, and an insulating layer may be provided instead of the substrate 101. In this case, the sensor portion 104 may be provided on the substrate, or the sensor portion 104 may be formed using the substrate. Alternatively, an insulating layer may be provided on the sensor portion 104, and the light-emitting element 110 may be provided on the insulating layer. The insulating layer preferably has a property of transmitting visible light.

[0096] In addition, in the display devices 100 shown in each of FIGS. 9A, 9B, 11A, and 11B, there may be cases where the protective member 105 does not need to be provided.

[0097] [Operation Example 2 of Electronic Device] An operation example of an electronic device according to another aspect of the present invention will be described. The operation of the electronic device having an eye-gaze tracking function using visible light is similar to the operation of the electronic device having an eye-gaze tracking function using infrared light, except that in step 210 shown in Fig. 7, the light-emitting element 110LS that emits visible light is used as a light source to illuminate the user's eyeball 108. Therefore, the explanation of [Operation Example 1 of Electronic Device] can be referred to for the operation example of the electronic device having an eye-gaze tracking function using visible light.

[0098] By using the present invention, it is possible to track the user's gaze. By tracking the user's gaze, it is possible to understand, for example, what the user is paying attention to, and analyze the user's behavior. It is also possible to make an avatar reproduce the user's eye movements. It is also possible to perform operations or menu selections using gaze.

[0099] At least a part of the configuration examples exemplified in this embodiment and the corresponding drawings can be appropriately combined with other configuration examples or drawings.

[0100] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0101] Embodiment 2 In this embodiment, structural examples of an electronic device according to one embodiment of the present invention and an electronic device to which a display device according to one embodiment of the present invention is applied will be described.

[0102] The display device of one embodiment of the present invention has an eye-tracking function and can increase resolution, and therefore can be suitably used in electronic devices for virtual reality or augmented reality. Alternatively, the display device of one embodiment of the present invention can be suitably used in electronic devices for substitutional reality (SR) or mixed reality (MR). Examples of the electronic device of one embodiment of the present invention and the electronic device to which the display device of one embodiment of the present invention is applied include head-mounted information terminals (wearable devices), such as head-mounted displays, eyeglasses-type terminals, and goggles-type terminals. In this specification and the like, the term "electronic device" may be interpreted as a head-mounted display, eyeglasses-type terminal, goggles-type terminal, or the like.

[0103] 12A to 12C show perspective views of electronic device 750. Fig. 12A is a perspective view showing the front, top, and left side of electronic device 750, and Figs. 12B and 12C are perspective views showing the back, bottom, and right side of electronic device 750.

[0104] The electronic device 750 includes a pair of display devices 751, a housing 752, a pair of mounting portions 754, a buffer member 755, and a pair of lenses 756. The pair of display devices 751 are provided inside the housing 752 at positions that can be viewed through the lenses 756.

[0105] Here, the pair of display devices 751 corresponds to the display device 100 shown in Fig. 1A. The pair of lenses 756 corresponds to the optical system 151 shown in Fig. 1A. Although not shown, the electronic device 750 shown in Figs. 12A to 12C includes, in a housing 752, the motion detection unit 153, the audio 154, the camera 155, the control unit 156, the communication unit 157, and the battery 158 described in the first embodiment.

[0106] The electronic device 750 is an electronic device for VR. A user wearing the electronic device 750 can view an image displayed on a display device 751 through a lens 756. Also, by displaying different images on a pair of display devices 751, a three-dimensional display using parallax can be performed.

[0107] An input terminal 757 and an output terminal 758 are provided on the rear side of the housing 752. A cable for supplying a video signal from a video output device or the like, or power for charging a battery provided inside the housing 752, can be connected to the input terminal 757. The output terminal 758 functions as, for example, an audio output terminal, and earphones, headphones, etc. can be connected to the output terminal 757.

[0108] The housing 752 preferably has a mechanism for adjusting the left-right positions of the lens 756 and the display device 751 so that they are optimally positioned according to the position of the user's eyes. Also, the housing 752 preferably has a mechanism for adjusting the focus by changing the distance between the lens 756 and the display device 751.

[0109] The display device of one embodiment of the present invention can be applied to the display device 751. Therefore, the electronic device 750 can display images with extremely high definition. This allows a user to feel a high sense of immersion.

[0110] The buffer member 755 is a portion that comes into contact with the user's face (forehead, cheeks, etc.). The close contact of the buffer member 755 with the user's face prevents light leakage and enhances the sense of immersion. The buffer member 755 is preferably made of a soft material so that it can closely contact the user's face when the user wears the electronic device 750. Materials such as rubber, silicone rubber, urethane, and sponge can be used. Furthermore, using a sponge or other material with a surface covered with cloth, leather (natural leather or synthetic leather), or the like, reduces the likelihood of gaps forming between the user's face and the buffer member 755, thereby effectively preventing light leakage. Furthermore, using such materials is preferable because they are pleasant to the touch and do not cause the user to feel cold when worn in cold weather. Components that come into contact with the user's skin, such as the buffer member 755 or the attachment portion 754, are preferably removable for easy cleaning or replacement.

[0111] The electronic device of this embodiment may further include an earphone 754A. The earphone 754A has a communication unit (not shown) and has a wireless communication function. The earphone 754A can output audio data using the wireless communication function. The earphone 754A may also have a vibration mechanism that functions as a bone conduction earphone.

[0112] 12C, the earphone 754A can be configured to be directly connected to the attachment portion 754 or connected by wire. The earphone 754B and the attachment portion 754 may have a magnet. This allows the earphone 754B to be fixed to the attachment portion 754 by magnetic force, which is preferable as it makes storage easier.

[0113] 13A to 13C are diagrams showing the appearance of an electronic device 8300. The electronic device 8300 includes a housing 8301, a display portion 8302, a band-shaped fixture 8304, and a pair of lenses 8305.

[0114] A user can view the display on the display portion 8302 through the lens 8305. Note that it is preferable to curve the display portion 8302 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, three-dimensional display using parallax can be performed. 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 provided for each eye of the user.

[0115] 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 definition. For example, even when the display is enlarged and viewed using the lens 8305 as shown in FIG. 13C , the pixels are difficult for the user to view. That is, the display portion 8302 can be used to allow the user to view a highly realistic image.

[0116] 13D is a diagram showing the appearance of the electronic device 8400. The electronic device 8400 includes a pair of housings 8401, an attachment portion 8402, and a buffer 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, three-dimensional display using parallax can be performed.

[0117] 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.

[0118] The display device of one embodiment of the present invention can be applied to the display portion 8404 .

[0119] The attachment portion 8402 preferably has plasticity and elasticity so that it can be adjusted according to the size of the user's face and does not slip off. Furthermore, a portion of the attachment portion 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 device, without the need for separate audio equipment such as earphones or speakers. The housing 8401 may also have a function for outputting audio data via wireless communication.

[0120] For the mounting portion 8402 and the buffer member 8403, the description of the buffer member 755 can be referred to.

[0121] FIG. 13E is a diagram showing the external appearance of electronic device 8200.

[0122] The electronic device 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.

[0123] 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.

[0124] The wearing unit 8201 may have 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, and may have a function of recognizing the line of sight. The wearing unit 8201 may also have a function of monitoring the user's pulse 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 have a function of displaying biometric information of the user on the display unit 8204 and a function of changing an image displayed on the display unit 8204 in accordance with the movement of the user's head.

[0125] The display device of one embodiment of the present invention can be applied to the display portion 8204 .

[0126] 14A shows a perspective view of electronic device 700. Electronic device 700 has a pair of display devices 701, a pair of housings 702, a pair of optical members 703, a pair of mounting portions 704, and the like.

[0127] The electronic device 700 can project an image displayed on the display device 701 onto a display area 706 of the optical member 703. Furthermore, because the optical member 703 is translucent, the user can see the image displayed in the display area 706 superimposed on a transmitted image visually recognized through the optical member 703. Therefore, the electronic device 700 is an electronic device capable of AR display.

[0128] One of the housings 702 is provided with a camera 705 that can capture an image in front of it. Although not shown, one of the housings 702 is provided with a connector to which a wireless receiver or a cable can be connected, and a video signal or the like can be supplied to the housing 702. The housing 702 can also be provided with an acceleration sensor such as a gyro sensor, which can detect the orientation of the user's head and display an image corresponding to that orientation in the display area 706. The housing 702 is preferably provided with a battery, which can be charged wirelessly or via a wired connection.

[0129] 14B , a method for projecting an image onto display area 706 of electronic device 700 will be described. A display device 701, a lens 711, and a reflector 712 are provided inside housing 702. In addition, a portion of optical member 703 corresponding to display area 706 has a reflecting surface 713 that functions as a half mirror.

[0130] Light 715 emitted from the display device 701 passes through a lens 711 and is reflected by a reflector 712 toward the optical member 703. Inside the optical member 703, the light 715 is repeatedly totally reflected at the end surface of the optical member 703 and reaches a reflecting surface 713, whereby an image is projected onto the reflecting surface 713. This allows the user to view both the light 715 reflected by the reflecting surface 713 and the transmitted light 716 that has passed through the optical member 703 (including the reflecting surface 713).

[0131] 14B shows an example in which the reflector 712 and the reflecting surface 713 each have a curved surface. This allows for greater freedom in optical design than when these surfaces are flat, and allows for a thinner optical member 703. Note that the reflector 712 and the reflecting surface 713 may also be flat.

[0132] A member having a mirror surface, preferably one with high reflectivity, can be used as the reflector 712. A half mirror utilizing reflection from a metal film may be used as the reflecting surface 713, but the transmittance of the transmitted light 716 can be increased by using a prism utilizing total reflection or the like.

[0133] Here, the housing 702 preferably has a mechanism for adjusting the distance between the lens 711 and the display device 701 or the angle therebetween. This makes it possible to adjust the focus, enlarge or reduce the size of an image, etc. For example, one or both of the lens 711 and the display device 701 may be configured to be movable in the optical axis direction.

[0134] Furthermore, the housing 702 preferably has a mechanism that can adjust the angle of the reflector 712. By changing the angle of the reflector 712, it is possible to change the position of the display area 706 where an image is displayed. This makes it possible to position the display area 706 in an optimal position according to the position of the user's eyes.

[0135] The display device of one embodiment of the present invention can be applied to the display device 701. Therefore, the electronic device 700 can provide an extremely high-definition display.

[0136] Note that the display device of one embodiment of the present invention may be applied to a display portion of an electronic device having a display function, in addition to the electronic devices described above. Examples of such electronic devices include electronic devices with relatively large screens, such as television devices, notebook personal computers, monitor devices, digital signage, pachinko machines, and game machines, as well as digital cameras, digital video cameras, digital photo frames, mobile phones, portable game machines, personal digital assistants, such as smartphones and tablets, and sound players.

[0137] In particular, electronic devices such as portable game consoles and smartphones can be used as, for example, VR devices by attaching a housing to which the electronic device is attached to the head using a band-like fixing part or attachment part, etc. Therefore, the display device of one embodiment of the present invention may be applied to the display part of the electronic device.

[0138] Furthermore, since the resolution of the display device of one embodiment of the present invention can be increased, it may be used in electronic devices having a relatively small display portion, such as wristwatch-type and bracelet-type information terminals (wearable devices).

[0139] 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.

[0140] 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.

[0141] The electronic device of this embodiment may have a sensor (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).

[0142] 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.

[0143] At least a part of the configuration examples exemplified in this embodiment and the corresponding drawings can be appropriately combined with other configuration examples or drawings.

[0144] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0145] Embodiment 3 An arithmetic circuit according to one embodiment of the present invention will be described. The arithmetic circuit can be used, for example, as an arithmetic circuit having a function of performing a product-sum operation. Note that the arithmetic circuit having a function of performing a product-sum operation can be referred to as an arithmetic circuit of a neural network.

[0146] First, a configuration example of an arithmetic circuit according to one embodiment of the present invention will be described. The arithmetic circuit can be applied to the image processing unit 121 described in the above embodiment.

[0147] The arithmetic circuit 350 shown in FIG. 15 includes, for example, an array portion ALP, a circuit ILD, a circuit WLD, a circuit XLD, a circuit AFP, and circuits TW[1] to TW[n] (n is an integer of 1 or more).

[0148] The circuit ILD and the circuit AFP are electrically connected to the wirings OL[1] to OL[n] and the wirings OLB[1] to OLB[n] via the circuits TW[1] to TW[n], respectively.

[0149] The circuits TW[1] to TW[n] function as switching circuits. In each of the circuits TW[1] to TW[n], it is possible to switch between inputting output signals from the wirings OL[1] to OL[n] and OLB[1] to OLB[n] to the circuit AFP and inputting output signals from the circuit ILD to the wirings OL[1] to OL[n] and OLB[1] to OLB[n].

[0150] The circuit WLD is electrically connected to the wirings WL[1] to WL[m] (m is an integer of 1 or more) and the wirings WX1L[1] to WX1L[m]. The circuit XLD is electrically connected to the wirings WX1L[1] to WX1L[m].

[0151] The arithmetic circuit 350 shown in Fig. 15 has circuits MP in which array units ALP are arranged in a matrix of m x n. Note that in Fig. 15, the circuit MP located in row i and column j (where i is an integer between 1 and m, and j is an integer between 1 and n) is represented as circuit MP[i,j]. However, Fig. 15 only illustrates circuit MP[1,1], circuit MP[1,n], circuit MP[i,j], circuit MP[m,1], and circuit MP[m,n], and does not illustrate other circuits MP.

[0152] The circuit MP[i,j] is electrically connected to the wiring WL[i], the wiring WX1L[i], the wiring OL[j], and the wiring OLB[j].

[0153] For example, the circuit MP[i,j] has a function of holding a weighting factor (also referred to as first data). The weighting factor may also be referred to as a weight value. Specifically, the circuit MP[i,j] holds information corresponding to the weighting factor input from the wiring OL[j] and the wiring OLB[j].

[0154] The circuit ILD has a function of outputting information corresponding to first data, which is a weight coefficient, to the wirings OL[1] to OL[n] and the wirings OLB[1] to OLB[n].

[0155] The information corresponding to the weighting coefficient may be, for example, a potential, a resistance value, a current value, etc. When a current value is used as the information corresponding to the weighting coefficient, the input current can be generated using a current output type digital-to-analog converter (IDAC).

[0156] Furthermore, the circuit MP[i,j] has a function of outputting the product of an input value (also referred to as second data) input from the wiring WX1L[i] and a weighting coefficient (first data). As a specific example, the circuit MP[i,j] receives the second data from the wiring WX1L[i] and outputs a current corresponding to the product of the first data and the second data to the wiring OL[j] and the wiring OLB[j]. Note that although FIG. 15 illustrates an example in which the wiring OL[j] and the wiring OLB[j] are provided, one embodiment of the present invention is not limited thereto. Only one of the wiring OL[j] and the wiring OLB[j] may be provided.

[0157] The circuit XLD has a function of supplying second data, which is an input value, to the wirings WX1L[1] to WX1L[m].

[0158] The information corresponding to the input value may be, for example, a potential, a current value, etc. When a current value is used as the information corresponding to the input value, the input current can be generated using a current output type digital-to-analog conversion circuit.

[0159] Currents corresponding to the product of the first data and the second data output from the circuits MP[1,j] to MP[m,j] are added together and output to the wiring OL[j] and the wiring OLB[j]. In this way, the arithmetic circuit can perform a product-sum operation on the weight coefficients and the input values.

[0160] The circuit XLD and the circuit WLD have a function of selecting a circuit MP to which information is to be written according to first data input from the circuit ILD. For example, when writing information to the circuits MP[i,1] to MP[i,n] located in the i-th row of the array portion ALP, the circuit XLD supplies a signal to the wiring WX1L[i] for turning on or off the first write switching elements included in each of the circuits MP[i,1] to MP[i,n] and supplies a potential to the wiring WX1L for turning off the first write switching elements included in each of the circuits MP other than the i-th row. The circuit WLD supplies a signal to the wiring WL[i] for turning on or off the second write switching elements included in each of the circuits MP[i,1] to MP[i,n] and supplies a potential to the wiring WL for turning off the second write switching elements included in each of the circuits MP other than the i-th row.

[0161] The circuit AFP includes circuits ACTF[1] to ACTF[n]. The circuit ACTF[j] is electrically connected to the wiring OL[j] and the wiring OLB[j] via a circuit TW[j] having a switching function. The circuit ACTF[j] generates a signal according to information (for example, a potential, a current value, or the like) corresponding to the result of a product-sum operation input from the wiring OL[j] and the wiring OLB[j], and ｊ （ｋ） The circuit AFP compares information (for example, potential, current value, etc.) corresponding to the results of the product-sum operation input from the wirings OL[1] to OL[n] and the wirings OLB[1] to OLB[n], generates a signal according to the comparison result, and outputs z １ （ｋ） ~z ｎ （ｋ） It can be output as:

[0162] <Circuit MP> Next, the circuit MP will be described. An example circuit configuration applicable to the circuit MP[i, j] is shown in FIG. 16. The circuit MP includes a circuit MC and a circuit MCr. The circuit MC also includes transistors M1 to M3 and a capacitor C1. Note that, for example, the transistor M2 and the capacitor C1 form a holding unit HC.

[0163] 16, the circuit MCr has a circuit configuration similar to that of the circuit MC, and therefore, the circuit elements of the circuit MCr are designated by the letter "r" to distinguish them from the circuit elements of the circuit MC.

[0164] The transistors M1 to M3 shown in FIG. 16 are, for example, n-channel transistors with a multi-gate structure having gates above and below the channel, and each of the transistors M1 to M3 has a first gate and a second gate.

[0165] Furthermore, the arithmetic circuit 350 described in this embodiment does not depend on the connection configuration of the back gates of the transistors. The back gates of the transistors M1 to M3 shown in FIG. 16 are illustrated, but the connection configuration of the back gates is not illustrated. However, the electrical connection destination of the back gates can be determined at the design stage. For example, in a transistor having a back gate, the gate and the back gate may be electrically connected to increase the on-state current of the transistor. That is, for example, the gate and the back gate of the transistor M2 may be electrically connected. Furthermore, in a transistor having a back gate, for example, a wiring electrically connected to an external circuit or the like may be provided to apply a potential to the back gate of the transistor from the external circuit or the like in order to change the threshold voltage of the transistor or reduce the off-state current of the transistor. Note that this also applies to transistors described elsewhere in this specification or illustrated in other drawings, not just FIG. 16.

[0166] Furthermore, the semiconductor device of one embodiment of the present invention does not depend on the structure of the transistors included in the semiconductor device. The transistors may have a single-gate structure. Furthermore, some of the transistors may have a back gate, and other transistors may not have a back gate. This also applies to transistors described elsewhere in the specification or illustrated in other drawings, as well as the circuit diagram in FIG. 16 .

[0167] Furthermore, in this specification and the like, transistors with various structures can be used as transistors. Therefore, there is no limitation on the type of transistor to be used. Examples of transistors that can be used include transistors having single crystal silicon, and transistors having non-single crystal semiconductor films typified by amorphous silicon, polycrystalline silicon, and microcrystalline (also called microcrystal, nanocrystal, or semi-amorphous) silicon. Alternatively, thin film transistors (TFTs) made of such semiconductors can be used. The use of TFTs offers various advantages. For example, TFTs can be manufactured at lower temperatures than single crystal silicon, which can reduce manufacturing costs or increase the size of manufacturing equipment.

[0168] As an example of a transistor, a transistor including a compound semiconductor (e.g., SiGe, GaAs, or the like) or an oxide semiconductor can be used. A transistor using an oxide semiconductor in a channel formation region may be called an OS transistor. Alternatively, a thin film transistor in which these compound semiconductors or these oxide semiconductors are thin-filmed can be used. These compound semiconductors or oxide semiconductors can be used not only for the channel portion of a transistor but also for other purposes. For example, these compound semiconductors or oxide semiconductors can be used as wirings, resistors, pixel electrodes, light-transmitting electrodes, or the like. Since these can be deposited or formed simultaneously with the transistor, costs can be reduced.

[0169] Examples of the oxide semiconductor include oxides containing at least one of indium, an element M (for example, the element M can be one or more elements selected from aluminum, gallium, yttrium, copper, vanadium, beryllium, boron, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, magnesium, etc.), and zinc.

[0170] As an example of a transistor, a transistor formed by an inkjet method or a printing method can be used. These methods allow manufacturing at room temperature, in a low vacuum, or on a large substrate. Therefore, manufacturing can be performed without using a mask (reticle), and the layout of the transistor can be easily changed. Furthermore, manufacturing can be performed without using a resist, which reduces material costs and the number of processes. Furthermore, since a film can be applied only to a necessary portion, material waste is reduced and costs can be reduced compared to a manufacturing method in which a film is formed on the entire surface and then etched.

[0171] As an example of a transistor, a transistor having an organic semiconductor or a carbon nanotube can be used. This allows a transistor to be formed on a flexible substrate. A device using a transistor having an organic semiconductor or a carbon nanotube can be made more resistant to impacts.

[0172] In the circuit MP of FIG. 16 , a first terminal of the transistor M1 is electrically connected to a wiring VE. A second terminal of the transistor M1 is electrically connected to a first terminal of the transistor M3. A gate of the transistor M1 is electrically connected to a first terminal of the capacitor C1 and a first terminal of the transistor M2. A second terminal of the capacitor C1 is electrically connected to a wiring VE. A second terminal of the transistor M2 is electrically connected to a wiring OL. A gate of the transistor M2 is electrically connected to a wiring WL. A second terminal of the transistor M3 is electrically connected to the wiring OL, and a gate of the transistor M3 is electrically connected to a wiring WX1L.

[0173] The circuit MCr has a different connection configuration from the circuit MC. The second terminal of the transistor M3r is electrically connected to a wiring OLB instead of the wiring OL. The first terminal of the transistor M1r and the second terminal of the capacitor C1r are electrically connected to a wiring VEr.

[0174] In the holding unit HC shown in FIG. 16, the electrical connection point between the gate of the transistor M1, the first terminal of the capacitor C1, and the first terminal of the transistor M2 is a node n1.

[0175] The holding unit HC has a function of holding a potential corresponding to the weighting coefficient (first data). The holding unit HC included in the circuit MC of FIG. 16 can hold the potential by inputting a current of a predetermined value from the wiring OL when the transistors M2 and M3 are turned on, writing a potential corresponding to the current value to the capacitor C1, and then turning off the transistor M2. This allows the potential of the node n1 to be held as a potential corresponding to the weighting coefficient (first data). At this time, a current is input from the wiring OL, and a potential corresponding to the magnitude of the current can be held in the capacitor C1. Therefore, the influence of variations in the current characteristics (such as the threshold voltage) of the transistor M1 on the input of the first data can be reduced.

[0176] The current input to the wiring OL can be input and generated using a current output type digital-to-analog converter circuit.

[0177] Furthermore, since the transistor M2 holds the potential of the node n1 for a long time, it is preferable to use a transistor with low off-state current as the transistor M2. As a transistor with low off-state current, for example, an OS transistor can be used. Since an oxide semiconductor with a wide band gap is used in a channel formation region of the OS transistor, the off-state current of the OS transistor can be reduced.

[0178] Alternatively, a transistor having a back gate may be used as the transistor M2, and a low-level potential may be applied to the back gate to shift the threshold voltage to the positive side and reduce the off-state current.

[0179] In this way, an arithmetic circuit with high arithmetic accuracy or high reliability is provided.

[0180] <Configuration Example 2 of Arithmetic Circuit> Another example of an arithmetic circuit MAC1 that performs a product-sum operation will be described below. The arithmetic circuit MAC1 can be applied to the image processing unit 121 described in the above embodiment.

[0181] 17 shows an example of the configuration of an arithmetic circuit that performs a product-sum operation on first data, which is positive or "0", and second data, which is also positive or "0". The arithmetic circuit MAC1 shown in FIG. 17 is a circuit that performs a product-sum operation on first data corresponding to the potential held in each cell and input second data, and calculates an activation function using the result of the product-sum operation. Note that the first data and the second data can be, for example, analog data or multi-valued data (discrete data).

[0182] The arithmetic circuit can also be called a memory because it also functions as a memory for storing first data. In particular, when analog data is used as the first data, it can be called an analog memory.

[0183] The arithmetic circuit MAC1 includes a circuit WCS, a circuit XCS, a circuit WSD, a circuit SWS1, a circuit SWS2, a cell array CA, and conversion circuits ITRZ[1] to ITRZ[n].

[0184] The cell array CA includes cells IM[1,1] to IM[m,n] (where m is an integer greater than or equal to 1 and n is an integer greater than or equal to 1) and cells IMref[1] to IMref[m]. Each of cells IM[1,1] to IM[m,n] has a function of holding a potential corresponding to an amount of current corresponding to first data, and cells IMref[1] to IMref[m] have a function of supplying the held potential and a potential corresponding to second data required for performing a product-sum operation to wirings XCL[1] to XCL[m].

[0185] Note that the cell array CA in Figure 17 has n+1 cells arranged in a matrix in the row direction and m cells arranged in the column direction, but the cell array CA may also be configured to have two or more cells arranged in a matrix in the row direction and one or more cells arranged in the column direction.

[0186] Each of cells IM[1,1] to IM[m,n] has, as an example, a transistor F1, a transistor F2, and a capacitance C5, and each of cells IMref[1] to IMref[m] has, as an example, a transistor F1m, a transistor F2m, and a capacitance C5m.

[0187] In particular, it is preferable that the sizes (e.g., channel length, channel width, transistor configuration, etc.) of the transistors F1 included in each of the cells IM[1,1] to IM[m,n] are equal to each other, and it is also preferable that the sizes of the transistors F2 included in each of the cells IM[1,1] to IM[m,n] are equal to each other. It is also preferable that the sizes of the transistors F1m included in each of the cells IMref[1] to IMref[m] are equal to each other, and it is also preferable that the sizes of the transistors F2m included in each of the cells IMref[1] to IMref[m] are equal to each other. It is also preferable that the sizes of the transistors F1 and F1m are equal to each other, and it is also preferable that the sizes of the transistors F2 and F2m are equal to each other.

[0188] Unless otherwise specified, the transistors F1 and F1m are considered to ultimately operate in a linear region when they are in an on state. That is, the gate voltage, source voltage, and drain voltage of each of the above-described transistors are considered to include a case where they are appropriately biased to voltages within a range in which they operate in a linear region. However, one aspect of the present invention is not limited to this. For example, the transistors F1 and F1m may operate in a saturation region when they are in an on state, or may operate in both a linear region and a saturation region.

[0189] Furthermore, unless otherwise specified, the transistors F2 and F2m are considered to operate in the subthreshold region (i.e., in the transistor F2 or F2m, the gate-source voltage is lower than the threshold voltage, more preferably, the drain current increases exponentially with the gate-source voltage). That is, the gate voltage, source voltage, and drain voltage of each of the above-mentioned transistors are considered to be appropriately biased to voltages within the range in which they operate in the subthreshold region. Therefore, the transistors F2 and F2m also include a case in which they operate such that an off-state current flows between the source and the drain.

[0190] For example, the transistor F1 and / or the transistor F1m is preferably the OS transistor described above. In addition, the channel formation region of the transistor F1 and / or the transistor F1m is preferably an oxide containing at least one of indium, an element M (for example, the element M can be one or more elements selected from aluminum, gallium, yttrium, copper, vanadium, beryllium, boron, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, magnesium, or the like), and zinc.

[0191] By using an OS transistor as the transistor F1 and / or the transistor F1m, leakage current of the transistor F1 and / or the transistor F1m can be suppressed, thereby reducing the power consumption of the arithmetic circuit. Specifically, when the transistor F1 and / or the transistor F1m is off, leakage current from the retention node to the write word line can be significantly reduced, thereby reducing the number of refresh operations of the potential of the retention node and reducing the power consumption of the arithmetic circuit. Furthermore, by significantly reducing the leakage current from the retention node to the write word line, the cell can retain the potential of the retention node for a long time, thereby improving the accuracy of the arithmetic circuit.

[0192] Furthermore, by using an OS transistor for the transistor F2 and / or the transistor F2m, the transistor F2 and / or the transistor F2m can operate over a wide current range in the subthreshold region, thereby reducing current consumption. Furthermore, by using an OS transistor for the transistor F2 and / or the transistor F2m, the transistor F2 and / or the transistor F2m can be manufactured simultaneously with the transistors F1 and F1m, which may shorten the manufacturing process of the arithmetic circuit. The transistor F2 and / or the transistor F2m can be a transistor containing silicon in a channel formation region (hereinafter referred to as a Si transistor) other than an OS transistor. Examples of silicon that can be used include amorphous silicon (sometimes referred to as hydrogenated amorphous silicon), microcrystalline silicon, polycrystalline silicon, and single crystal silicon.

[0193] Incidentally, when an arithmetic circuit or the like is highly integrated on a chip, the chip may generate heat due to the operation of the circuit. This heat increases the temperature of the transistor, which may change the characteristics of the transistor, resulting in a change in field-effect mobility or a decrease in operating frequency. OS transistors have higher heat resistance than Si transistors, so their field-effect mobility is less likely to change due to temperature changes, and their operating frequency is less likely to decrease. Furthermore, OS transistors tend to maintain the characteristic that their drain current increases exponentially with respect to the gate-source voltage, even at high temperatures. Therefore, by using OS transistors, it is easy to perform the product-sum operation (described later) even in high-temperature environments. Therefore, when configuring an arithmetic circuit that is resistant to heat generation due to operation, it is preferable to use OS transistors as the transistors.

[0194] In each of the cells IM[1,1] to IM[m,n], the first terminal of the transistor F1 is electrically connected to the gate of the transistor F2. The first terminal of the transistor F2 is electrically connected to the wiring VE. The first terminal of the capacitor C5 is electrically connected to the gate of the transistor F2.

[0195] In each of the cells IMref[1] to IMref[m], the first terminal of the transistor F1m is electrically connected to the gate of the transistor F2m. The first terminal of the transistor F2m is electrically connected to the wiring VE. The first terminal of the capacitor C5m is electrically connected to the gate of the transistor F2m.

[0196] The arithmetic circuit described in this embodiment does not depend on the polarity of the transistors included in the arithmetic circuit. For example, although the transistors F1 and F2 shown in FIG. 17 are n-channel transistors, some or all of the transistors may be replaced with p-channel transistors.

[0197] The above-described modifications to the structure and polarity of the transistors are not limited to the transistors F1 and F2. For example, the same applies to transistors F1m, F2m, transistors F3[1] to F3[n] and transistors F4[1] to F4[n] described later, and further to transistors described elsewhere in the specification or illustrated in other drawings.

[0198] The wiring VE is a wiring for passing current between the first terminal and the second terminal of the transistor F2 of each of the cells IM[1,1], IM[m,1], IM[1,n], and IM[m,n], and also functions as a wiring for passing current between the first terminal and the second terminal of the transistor F2 of each of the cells IMref[1] and IMref[m]. As an example, the wiring VE functions as a wiring for supplying a constant voltage. The constant voltage may be, for example, a low-level potential or a ground potential.

[0199] In the cell IM[1,1], the second terminal of the transistor F1 is electrically connected to the wiring WCL[1], and the gate of the transistor F1 is electrically connected to the wiring WSL[1]. The second terminal of the transistor F2 is electrically connected to the wiring WCL[1], and the second terminal of the capacitor C5 is electrically connected to the wiring XCL[1]. In FIG. 17 , the node NN[1,1] is the connection point between the first terminal of the transistor F1, the gate of the transistor F2, and the first terminal of the capacitor C5 in the cell IM[1,1].

[0200] In the cell IM[m,1], the second terminal of the transistor F1 is electrically connected to the wiring WCL[1], and the gate of the transistor F1 is electrically connected to the wiring WSL[m]. The second terminal of the transistor F2 is electrically connected to the wiring WCL[1], and the second terminal of the capacitor C5 is electrically connected to the wiring XCL[m]. In FIG. 17 , the node NN[m,1] is the connection point between the first terminal of the transistor F1, the gate of the transistor F2, and the first terminal of the capacitor C5 in the cell IM[m,1].

[0201] In the cell IM[1,n], the second terminal of the transistor F1 is electrically connected to the wiring WCL[n], and the gate of the transistor F1 is electrically connected to the wiring WSL[1]. The second terminal of the transistor F2 is electrically connected to the wiring WCL[n], and the second terminal of the capacitor C5 is electrically connected to the wiring XCL[1]. In FIG. 17 , the connection point between the first terminal of the transistor F1, the gate of the transistor F2, and the first terminal of the capacitor C5 in the cell IM[1,n] is designated as the node NN[1,n].

[0202] In the cell IM[m,n], the second terminal of the transistor F1 is electrically connected to the wiring WCL[n], and the gate of the transistor F1 is electrically connected to the wiring WSL[m]. The second terminal of the transistor F2 is electrically connected to the wiring WCL[n], and the second terminal of the capacitor C5 is electrically connected to the wiring XCL[m]. In FIG. 17 , the node NN[m,n] is the connection point between the first terminal of the transistor F1, the gate of the transistor F2, and the first terminal of the capacitor C5 in the cell IM[m,n].

[0203] In the cell IMref[1], the second terminal of the transistor F1m is electrically connected to the wiring XCL[1], and the gate of the transistor F1m is electrically connected to the wiring WSL[1]. The second terminal of the transistor F2m is electrically connected to the wiring XCL[1], and the second terminal of the capacitor C5 is electrically connected to the wiring XCL[1]. Note that in FIG. 17 , the connection point between the first terminal of the transistor F1m, the gate of the transistor F2m, and the first terminal of the capacitor C5 in the cell IMref[1] is referred to as the node NNref[1].

[0204] In the cell IMref[m], the second terminal of the transistor F1m is electrically connected to the wiring XCL[m], and the gate of the transistor F1m is electrically connected to the wiring WSL[m]. The second terminal of the transistor F2m is electrically connected to the wiring XCL[m], and the second terminal of the capacitor C5 is electrically connected to the wiring XCL[m]. In FIG. 17 , the node NNref[m] is the connection point between the first terminal of the transistor F1m, the gate of the transistor F2m, and the first terminal of the capacitor C5 in the cell IMref[m].

[0205] The above-mentioned nodes NN[1,1], NN[m,1], NN[1,n], NN[m,n], NNref[1], and NNref[m] function as holding nodes for the respective cells.

[0206] In cells IM[1,1] to IM[m,n], for example, when transistor F1 is in an on state, transistor F2 is diode-connected. When transistor F1 is in an on state and a current of an amount I flows from wiring WCL to the second terminal of transistor F2, with the constant voltage provided by wiring VE serving as ground potential (GND), the potential of the gate (node ​​NN) of transistor F2 is determined according to the current amount I. Note that, because transistor F1 is in an on state, the potential of the second terminal of transistor F2 is ideally equal to the potential of the gate (node ​​NN) of transistor F2. By turning transistor F1 off, the potential of the gate (node ​​NN) of transistor F2 is maintained. This allows transistor F2 to pass a current of an amount I between its source and drain, depending on the ground potential of the first terminal of transistor F2 and the potential of the gate (node ​​NN) of transistor F2. In this specification, this operation is referred to as "the amount of current flowing between the source and drain of the transistor F2 is programmed to I", etc.

[0207] The circuit SWS1 includes, for example, transistors F3[1] to F3[n]. A first terminal of the transistor F3[1] is electrically connected to the wiring WCL[1], a second terminal of the transistor F3[1] is electrically connected to the circuit WCS, and a gate of the transistor F3[1] is electrically connected to the wiring SWL1. A first terminal of the transistor F3[n] is electrically connected to the wiring WCL[n], a second terminal of the transistor F3[n] is electrically connected to the circuit WCS, and a gate of the transistor F3[n] is electrically connected to the wiring SWL1.

[0208] The transistors F3[1] to F3[n] are preferably OS transistors that can be used as the transistor F1 and / or the transistor F2, for example.

[0209] The circuit SWS1 functions as a circuit that brings the circuit WCS and each of the wirings WCL[1] to WCL[n] into a conductive state or a non-conductive state.

[0210] The circuit SWS2 includes, for example, transistors F4[1] to F4[n]. A first terminal of the transistor F4[1] is electrically connected to the wiring WCL[1], a second terminal of the transistor F4[1] is electrically connected to the input terminal of the conversion circuit ITRZ[1], and a gate of the transistor F4[1] is electrically connected to the wiring SWL2. A first terminal of the transistor F4[n] is electrically connected to the wiring WCL[n], a second terminal of the transistor F4[n] is electrically connected to the input terminal of the conversion circuit ITRZ[n], and a gate of the transistor F4[n] is electrically connected to the wiring SWL2.

[0211] The transistors F4[1] to F4[n] are preferably OS transistors that can be used for the transistor F1 and / or the transistor F2, for example.

[0212] The circuit SWS2 functions as a circuit that brings the wiring WCL[1] and the conversion circuit ITRZ[1] and the wiring WCL[n] and the conversion circuit ITRZ[n] into a conductive state or a non-conductive state.

[0213] The circuit WCS has a function of supplying data to be stored in each cell of the cell array CA.

[0214] The circuit XCS is electrically connected to the wirings XCL[1] to XCL[m]. The circuit XCS has a function of supplying a current corresponding to the reference data or a current corresponding to the second data to each of the cells IMref[1] to IMref[m] included in the cell array CA.

[0215] The circuit WSD is electrically connected to the wirings WSL[1] to WSL[m]. When writing first data to the cells IM[1,1] to IM[m,n], the circuit WSD has a function of selecting a row of the cell array CA to which the first data is to be written by supplying a predetermined signal to the wirings WSL[1] to WSL[m].

[0216] The circuit WSD is electrically connected to, for example, a wiring SWL1 and a wiring SWL2. The circuit WSD has a function of bringing the circuit WCS and the cell array CA into a conductive state or a non-conductive state by supplying a predetermined signal to the wiring SWL1, and a function of bringing the conversion circuits ITRZ[1] to ITRZ[n] and the cell array CA into a conductive state or a non-conductive state by supplying a predetermined signal to the wiring SWL2.

[0217] Each of the conversion circuits ITRZ[1] to ITRZ[n] has, for example, an input terminal and an output terminal. For example, the output terminal of the conversion circuit ITRZ[1] is electrically connected to the wiring OL[1], and the output terminal of the conversion circuit ITRZ[n] is electrically connected to the wiring OL[n].

[0218] Each of the conversion circuits ITRZ[1] to ITRZ[n] has a function of converting a current input to an input terminal into a voltage corresponding to the current and outputting the voltage from an output terminal. The voltage can be, for example, an analog voltage or a digital voltage. Each of the conversion circuits ITRZ[1] to ITRZ[n] may include a function-based arithmetic circuit. In this case, for example, the arithmetic circuit may perform a function calculation using the converted voltage, and the calculation result may be output to the wiring OL[1] to wiring OL[n].

[0219] In particular, when performing calculations on a hierarchical neural network, the above-mentioned functions may be, for example, a sigmoid function, a tanh function, a softmax function, a ReLU function, a threshold function, or the like.

[0220] A current output type digital-to-analog conversion circuit can be used as the circuit WCS shown in Fig. 17. Also, a current output type digital-to-analog conversion circuit can be used as the circuit XCS shown in Fig. 17.

[0221] At least a part of the configuration examples exemplified in this embodiment and the corresponding drawings can be appropriately combined with other configuration examples or drawings.

[0222] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0223] Embodiment 4 In this embodiment, a schematic top view and a schematic cross-sectional view of a light-emitting element and its periphery included in a display device, a configuration example of the light-emitting element, a configuration example of the light-emitting element and the light-receiving element, and a configuration example of the display device will be described.

[0224] 18A to 23B , a configuration example of a display device included in an electronic device having an eye-gaze tracking function using infrared light will be described. Note that the following description may also include a description of a configuration example of a display device included in an electronic device having an eye-gaze tracking function using visible light.

[0225] 18A is a schematic top view illustrating a configuration example in which a light-emitting element and a light-receiving element are arranged in one pixel in a display device 10 of one embodiment of the present invention. The display device 10 includes a plurality of light-emitting elements 61R that emit red light, a plurality of light-emitting elements 61G that emit green light, a plurality of light-emitting elements 61B that emit blue light, a plurality of light-emitting elements 61IR that emit infrared light, and a plurality of light-receiving elements 62.

[0226] In the following, when describing matters common to the light-emitting element 61R, the light-emitting element 61G, the light-emitting element 61B, and the light-emitting element 61IR, as well as the light-emitting element 61LS described later, the symbols attached to the reference numerals may be omitted and the light-emitting element may be described as the light-emitting element 61. Alternatively, when the light-emitting element 61 is described, it may refer to one or more of the light-emitting element 61R, the light-emitting element 61G, the light-emitting element 61B, the light-emitting element 61IR, and the light-emitting element 61LS.

[0227] 18A, in order to easily distinguish between the light-emitting elements 61, the light-emitting regions of the light-emitting elements 61 are labeled with R, G, B, and IR. Also, the light-receiving regions of the light-receiving elements 62 are labeled with PD.

[0228] 18A corresponds to display device 100 in embodiment 1. Light-emitting element 61R, light-emitting element 61G, light-emitting element 61B, and light-emitting element 61IR correspond to light-emitting element 110R, light-emitting element 110G, light-emitting element 110B, and light-emitting element 110IR, respectively, in embodiment 1. Light-receiving element 62 corresponds to the light-receiving element of sensor unit 104 in embodiment 1.

[0229] The light-emitting elements 61R, 61G, 61B, 61IR, and the light-receiving elements 62 are arranged in a matrix. Figure 18A illustrates an example in which the light-emitting elements 61R, 61G, 61B, and 61IR are arranged in the X direction, and the light-receiving elements 62 are arranged in the Y direction (a direction intersecting the X direction) relative to these light-emitting elements. Figure 18A also illustrates an example in which light-emitting elements 61 emitting light of the same color are arranged in the Y direction intersecting the X direction. In the display device 10 illustrated in Figure 18A, a pixel 80 can be configured, for example, by sub-pixels including the light-emitting elements 61R, 61G, 61B, and 61IR arranged in the X direction, and a sub-pixel including the light-receiving element 62 arranged in the Y direction relative to these sub-pixels. The light-receiving elements 62 illustrated in Figure 18A have a function of detecting infrared light.

[0230] 18A shows a so-called stripe arrangement in which light-emitting elements of the same color are arranged in one direction. However, the arrangement method of the light-emitting elements is not limited to this, and arrangement methods such as a delta arrangement or a zigzag arrangement may also be applied, or a pentile arrangement may also be used.

[0231] As the light-emitting element 61R, the light-emitting element 61G, the light-emitting element 61B, and the light-emitting element 61IR, and the light-emitting element 61LS described later, it is preferable to use an EL element such as an OLED (organic light-emitting diode) or a QLED (quantum-dot light-emitting diode). Examples of the light-emitting substance contained in the EL element include a fluorescent substance (fluorescent material), a phosphorescent substance (phosphorescent material), an inorganic compound (such as a quantum dot material), and a substance that exhibits thermally activated delayed fluorescence (thermally activated delayed fluorescence: TADF material).

[0232] For example, a pn-type or pin-type photodiode can be used as the light receiving element 62. The light receiving element 62 functions as a photoelectric conversion element that detects light incident on the light receiving element 62 and generates electric charges. The amount of electric charges generated is determined based on the amount of incident light.

[0233] In particular, it is preferable to use an organic photodiode having a layer containing an organic compound as the light receiving element 62. Organic photodiodes can be easily made thin, lightweight, and large in area, and have a high degree of freedom in shape and design, making them applicable to a variety of display devices.

[0234] In one embodiment of the present invention, an organic EL element is used as the light-emitting element 61, and an organic photodiode is used as the light-receiving element 62. The organic EL element and the organic photodiode can be formed over the same substrate. Therefore, the organic photodiode can be built into a display device using the organic EL element.

[0235] Incidentally, when different light-emitting layers are formed for light-emitting elements of different colors, it is known to form them by a vapor deposition method using a shadow mask such as a metal mask or an FMM (fine metal mask, high-resolution metal mask). Note that in this specification, elements formed in this manner are sometimes referred to as an MM (metal mask) structure. However, with an MM structure, various factors, such as the accuracy of the metal mask, misalignment between the metal mask and the substrate, deflection of the metal mask, and the spread of the contours of the deposited film due to vapor scattering, can cause deviations in the shape and position of the island-shaped organic film from the design, making it difficult to achieve high definition and a high aperture ratio. Therefore, measures have been taken to artificially increase the definition (also known as pixel density) by applying special pixel arrangement methods such as a pentile arrangement.

[0236] For example, the light-emitting layer is processed into a fine pattern without using a metal mask or a shadow mask such as FMM. Specifically, the light-emitting layer is processed into a fine pattern using a photolithography method. In this specification, an element formed as described above may be referred to as an element having an MML (metal maskless) structure. By using the MML structure, a display device with high definition and a high aperture ratio, which have been difficult to achieve until now, can be realized. Furthermore, since the light-emitting layer can be separately fabricated, a display device with extremely vivid images, high contrast, and high display quality can be realized.

[0237] For simplicity, the following description will discuss the case where separate light-emitting layers for two-color light-emitting elements are formed. First, a first light-emitting film and a first sacrificial film are stacked to cover two pixel electrodes. Next, a resist mask is formed on the first sacrificial film at a position overlapping one of the pixel electrodes (first pixel electrode). Next, the resist mask, a portion of the first sacrificial film, and a portion of the first light-emitting film are etched. The etching is terminated when the other pixel electrode (second pixel electrode) is exposed. This allows a portion of the first light-emitting film (also referred to as the first light-emitting layer) processed into a strip or island shape to be formed on the first pixel electrode, and a portion of the sacrificial film (also referred to as the first sacrificial layer) to be formed thereon. Note that in this specification, the sacrificial film may also be referred to as a mask film. The sacrificial layer may also be referred to as a mask layer.

[0238] Next, a second light-emitting film and a second sacrificial film are laminated and formed. Then, resist masks are formed at positions overlapping the first pixel electrode and at positions overlapping the second pixel electrode. Next, the resist mask, a portion of the second sacrificial film, and a portion of the second light-emitting film are etched in the same manner as above. As a result, a first light-emitting layer and a first sacrificial layer are provided on the first pixel electrode, and a second light-emitting layer and a second sacrificial layer are provided on the second pixel electrode, respectively. In this way, the first light-emitting layer and the second light-emitting layer can be separately formed. Finally, the first sacrificial layer and the second sacrificial layer are removed to expose the first light-emitting layer and the second light-emitting layer, and then a common electrode is formed, thereby separately forming two-color light-emitting elements.

[0239] Furthermore, by repeating the above steps, it is possible to form light-emitting layers for light-emitting elements of three or more colors, thereby realizing a display device having light-emitting elements of three or four or more colors.

[0240] Here, in order to supply a potential to the common electrode, an electrode (also referred to as a first electrode, a connection electrode, etc.) can be provided on the same surface as the pixel electrode and electrically connected to the common electrode. The connection electrode is disposed outside the display region where the pixels are provided. Here, in order to prevent the upper surface of the connection electrode from being exposed to etching when the first light-emitting film is etched, a first sacrificial layer is preferably provided on the connection electrode as well. Similarly, when the second light-emitting film is etched, a second sacrificial layer is preferably provided on the connection electrode. The first sacrificial layer and the second sacrificial layer provided on the connection electrode can be removed by etching simultaneously with the first sacrificial layer on the first light-emitting layer and the second sacrificial layer on the second light-emitting layer.

[0241] For example, while it is difficult to achieve a distance of less than 10 μm between light-emitting layers of different colors with an MM structure, with an MML structure, it is possible to narrow the distance to 6 μm or less, 4 μm or less, 3 μm or less, 2 μm or less, or even 1 μm or less. Furthermore, by using an exposure device for LSIs, for example, the distance can be narrowed to 500 nm or less, 200 nm or less, 100 nm or less, or even 50 nm or less. This significantly reduces the area of ​​the non-light-emitting region that may exist between two light-emitting elements, enabling the aperture ratio to approach 100%. For example, the aperture ratio can be 50% or more, 60% or more, 70% or more, 80% or more, or even 90% or more, and even less than 100%.

[0242] Furthermore, the pattern of the light-emitting layer itself can be made much smaller than when a metal mask is used. For example, when a metal mask is used to create separate light-emitting layers, thickness variations occur between the center and edges of the pattern, resulting in a smaller effective area that can be used as the light-emitting region relative to the overall area of ​​the pattern. On the other hand, with the above-described fabrication method, a pattern is formed by processing a film formed to a uniform thickness, making it possible to achieve a uniform thickness within the pattern, and even with a fine pattern, almost the entire area can be used as the light-emitting region. Therefore, the above-described fabrication method can achieve both high definition and a high aperture ratio.

[0243] In this way, according to the above-described manufacturing method, a display device integrating minute light-emitting elements can be realized, and therefore there is no need to apply a special pixel arrangement method such as a pen tile method to artificially increase the resolution. Therefore, it is possible to realize a display device with a so-called stripe arrangement in which R, G, and B are each arranged in one direction, and with a resolution of 500 ppi or more, 1000 ppi or more, 2000 ppi or more, or even 3000 ppi or more, or even 5000 ppi or more.

[0244] 18A shows a common electrode 81 and a connection electrode 82. Here, the connection electrode 82 is electrically connected to the common electrode 81. The connection electrode 82 is provided outside the display area where the light-emitting elements 61 and the light-receiving elements 62 are arranged. Also in FIG. 18A, the common electrode 81 having an area overlapping with the light-emitting elements 61, the light-receiving elements 62, and the connection electrode 82 is shown by a dashed line.

[0245] The connection electrodes 82 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, when the top surface shape of the display area is rectangular, the top surface shape of the connection electrodes 82 can be strip-shaped, L-shaped, U-shaped (square bracket-shaped), quadrangular, etc.

[0246] Fig. 18B is a schematic top view showing an example of the configuration of the display device 10, which is a modified example of the display device 10 shown in Fig. 18A. The display device 10 shown in Fig. 18B differs from the display device 10 shown in Fig. 18A in that the light receiving elements 62 and the light emitting elements 61IR are arranged alternately in the X direction.

[0247] 18B , the light-emitting elements 61R, 61G, and 61B are arranged in different rows from the light-emitting element 61IR. This allows the widths (lengths in the X direction) of the light-emitting elements 61R, 61G, and 61B to be increased, thereby increasing the brightness of the light emitted by the pixel 80.

[0248] Fig. 19A is a schematic top view showing an example of the configuration of the display device 10, which is a modified example of the display device 10 shown in Fig. 18B. The display device 10 shown in Fig. 19A differs from the display device 10 shown in Fig. 18B in that the light-emitting elements 61 are arranged in the order G, B, R in the X direction instead of the order R, G, B. Also, it differs from the display device 10 shown in Fig. 18B in that the light-receiving element 62 is provided below the light-emitting elements 61G and 61B, and the light-emitting element 61IR is provided below the light-emitting element 61R.

[0249] The area occupied by the light receiving element 62 in the display device 10 shown in Fig. 19A is larger than the area occupied by the light receiving element 62 in the display device 10 shown in Fig. 18B. This increases the sensitivity of light detection by the light receiving element 62. Therefore, for example, if the display device 10 has an eye-tracking function, it can track the eye gaze with high accuracy. The area occupied by the light receiving element 62 can be rephrased as the area of ​​the light receiving element 62 when viewed from above.

[0250] Fig. 19B is a schematic top view showing an example of the configuration of the display device 10, which is a modified example of the display device 10 shown in Fig. 19A. The display device 10 shown in Fig. 19B differs from the display device 10 shown in Fig. 19A in that the light receiving element 62 is provided below the light emitting element 61G, and the light emitting element 61IR is provided below the light emitting elements 61B and 61R.

[0251] The area occupied by the light receiving elements 62 in the display device 10 shown in FIG. 19B is smaller than the area occupied by the light receiving elements 62 in the display device 10 shown in FIG. 19A . By narrowing the area occupied by the light receiving elements 62, the light receiving range of each light receiving element 62 can be narrowed. This reduces the overlap of the light receiving ranges between different light receiving elements 62, for example, between adjacent light receiving elements 62. This prevents the image captured using the light receiving elements 62 from becoming blurred, making it difficult to capture a clear image. For the above reasons, if the display device 10 has an eye tracking function, for example, reducing the area occupied by the light receiving elements 62 is preferable because it allows for clear imaging of the eyeball, etc., and improves authentication accuracy.

[0252] Here, the display devices 10 shown in each of FIGS. 18A, 18B, 19A, and 19B correspond to the display device 100 shown in FIG. 3B.

[0253] Fig. 20A is a cross-sectional view corresponding to dashed dotted line A1-A2 in Fig. 18B, Fig. 20B is a cross-sectional view corresponding to dashed dotted line B1-B2 in Fig. 18B. Fig. 20C is a cross-sectional view corresponding to dashed dotted line C1-C2 in Fig. 18B, and Fig. 20D is a cross-sectional view corresponding to dashed dotted line D1-D2 in Fig. 18B. The light-emitting element 61R, the light-emitting element 61G, the light-emitting element 61B, the light-emitting element 61IR, and the light-receiving element 62 are provided on a substrate 83.

[0254] In this specification and the like, for example, when it is said that "B is on A" or "B is below A", it is not necessary that there is an area where A and B are in contact with each other.

[0255] The substrate 83 may be a substrate having heat resistance sufficient to withstand at least subsequent heat treatment. When an insulating substrate is used as the substrate 83, a glass substrate, a quartz substrate, a sapphire substrate, a ceramic substrate, an organic resin substrate, or the like may be used. Furthermore, 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 may be used. However, when used in the display devices shown in FIGS. 2A , 2B , 5A , 5B , 9A , and 11A , it is preferable to use a light-transmitting material such as a glass substrate for the substrate 83.

[0256] In particular, it is preferable to use a substrate having a semiconductor circuit including semiconductor elements such as transistors formed on the semiconductor substrate or insulating substrate as the substrate 83. The semiconductor circuit preferably comprises, 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.

[0257] The substrate 83 corresponds to the substrate 101 in the first embodiment.

[0258] 20A shows an example of the cross-sectional configuration of light-emitting elements 61R, 61G, and 61B. The light-emitting element 61R has a pixel electrode 84R, a hole injection layer 85R, a hole transport layer 86R, a light-emitting layer 87R, an electron transport layer 88R, a common layer 89, and a common electrode 81. The light-emitting element 61G has a pixel electrode 84G, a hole injection layer 85G, a hole transport layer 86G, a light-emitting layer 87G, an electron transport layer 88G, a common layer 89, and a common electrode 81. The light-emitting element 61B has a pixel electrode 84B, a hole injection layer 85B, a hole transport layer 86B, a light-emitting layer 87B, an electron transport layer 88B, a common layer 89, and a common electrode 81.

[0259] 20B shows an example of the cross-sectional configuration of the light-emitting element 61IR and the light-receiving element 62. The light-emitting element 61IR has a pixel electrode 84IR, a hole injection layer 85IR, a hole transport layer 86IR, a light-emitting layer 87IR, an electron transport layer 88IR, a common layer 89, and a common electrode 81. The light-receiving element 62 has a pixel electrode 84PD, a hole transport layer 86PD, a light-receiving layer 90, an electron transport layer 88PD, a common layer 89, and a common electrode 81.

[0260] In the following, when describing matters common to the pixel electrodes 84R, 84G, 84B, 84IR, and 84PD, the symbols attached to the reference numerals may be omitted and the description may be made as pixel electrodes 84. Similarly, when describing matters common to the hole injection layer 85R, 85G, 85B, and 85IR, the symbols attached to the reference numerals may be omitted and the description may be made as hole injection layer 85. Similarly, when describing matters common to the hole transport layer 86R, 86G, 86B, 86IR, and 86PD, the symbols attached to the reference numerals may be omitted and the description may be made as hole transport layer 86. Similarly, when describing matters common to light-emitting layer 87R, light-emitting layer 87G, light-emitting layer 87B, and light-emitting layer 87IR, the symbols attached to the reference numerals may be omitted and the layer may be described as light-emitting layer 87. Similarly, when describing matters common to electron transport layer 88R, electron transport layer 88G, electron transport layer 88B, electron transport layer 88IR, and electron transport layer 88PD, the symbols attached to the reference numerals may be omitted and the layer may be described as electron transport layer 88.

[0261] The common layer 89 functions as an electron injection layer in the light-emitting element 61. On the other hand, the common layer 89 functions as an electron transport layer in the light-receiving element 62. For this reason, the light-receiving element 62 may not necessarily have the electron transport layer 88PD.

[0262] The hole injection layer 85, the hole transport layer 86, the electron transport layer 88, and the common layer 89 can also be referred to as functional layers. The light-emitting element has an EL layer between a pair of electrodes. Therefore, in the light-emitting element 61 shown in FIG. 20A and other figures, the hole injection layer 85, the hole transport layer 86, the light-emitting layer 87, the electron transport layer 88, and the common layer 89 can be collectively referred to as an EL layer.

[0263] The pixel electrode 84, the hole injection layer 85, the hole transport layer 86, the light emitting layer 87, and the electron transport layer 88 can be provided separately for each element. The common layer 89 and the common electrode 81 are provided in common to the light emitting element 61R, the light emitting element 61G, the light emitting element 61B, the light emitting element 61IR, and the light receiving element 62.

[0264] 20A, etc., the light-emitting element 61 and the light-receiving element 62 may have a hole-blocking layer and an electron-blocking layer. The light-emitting element 61 and the light-receiving element 62 may also have a layer containing a bipolar substance (a substance with high electron-transporting and hole-transporting properties) or the like.

[0265] A gap is provided between the common layer 89 and the insulating layer 92. This prevents the common layer 89 from coming into contact with the side surfaces of the light-emitting layer 87, the light-receiving layer 90, the hole transport layer 86, and the hole injection layer 85. This prevents short circuits in the light-emitting element 61 and the light-receiving element 62.

[0266] The voids are more easily formed, for example, as the distance between the light-emitting layers 87 becomes shorter. For example, the voids can be suitably formed when the distance is 1 μm or less, preferably 500 nm or less, and more preferably 200 nm or less, 100 nm or less, 90 nm or less, 70 nm or less, 50 nm or less, 30 nm or less, 20 nm or less, 15 nm or less, or 10 nm or less.

[0267] 20A and other drawings illustrate a configuration in which, from bottom to top, the light-emitting element 61 includes a pixel electrode 84, a hole injection layer 85, a hole transport layer 86, a light-emitting layer 87, an electron transport layer 88, a common layer 89 (electron injection layer), and a common electrode 81, and the light-receiving element 62 includes, from bottom to top, a pixel electrode 84PD, a hole transport layer 86PD, a light-receiving layer 90, an electron transport layer 88PD, a common layer 89, and a common electrode 81. However, one embodiment of the present invention is not limited to this. For example, the light-emitting element 61 may include, from bottom to top, a pixel electrode, an electron injection layer, an electron transport layer, a light-emitting layer, a hole transport layer, a hole injection layer, and a common electrode, and the light-receiving element 62 may include, from bottom to top, a pixel electrode, an electron transport layer, a light-receiving layer, a hole transport layer, and a common electrode. In this case, the hole injection layer of the light-emitting element 61 may be a common layer, and the common layer may be provided between the hole transport layer of the light-receiving element 62 and the common electrode. In the light-emitting element 61, the electron injection layer can be separated for each element.

[0268] Note that by using an MML structure for the light-emitting element 61 and the light-receiving element 62, the light-emitting element 61 and the light-receiving element 62 can have different configurations. For example, the light-emitting element 61 may be configured to include, from bottom to top, a pixel electrode 84, a hole injection layer 85, a hole transport layer 86, a light-emitting layer 87, an electron transport layer 88, a common layer 89 (electron injection layer), and a common electrode 81, while the light-receiving element 62 may be configured to include, from bottom to top, a pixel electrode 84PD, an electron transport layer 88PD, a light-receiving layer 90, a hole transport layer 86PD, the common layer 89, and a common electrode 81. This configuration allows the drive voltages of the light-emitting element 61 and the light-receiving element 62 to be in the same direction. Note that in the light-receiving element 62 with this configuration, a hole injection layer may be provided between the hole transport layer 86PD and the common layer 89.

[0269] In the following description, the electron transport layer is assumed to be provided above the hole transport layer. However, the following description can also be applied to the case where the electron transport layer is provided below the hole transport layer, for example, by replacing "electrons" with "holes" and "holes" with "electrons."

[0270] The hole injection layer is a layer that injects holes from the anode into the hole transport layer and contains a material with high hole injection properties, such as an aromatic amine compound and a composite material containing a hole transport material and an acceptor material (electron acceptor material).

[0271] The hole transport layer is a layer that transports holes injected from the anode by the hole injection layer to the light emitting layer. The hole transport layer is a layer that contains a hole transport material. The hole transport material is a material having a concentration of 1×10 −６ cm ２ A substance having a hole mobility of 1 / Vs or more is preferred. Note that other substances 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.

[0272] The electron transport layer is a layer that transports electrons injected from the cathode by the electron injection layer to the light emitting layer. The electron transport layer is a layer that contains an electron transporting material. The electron transporting material is a material having a molecular weight of 1×10 −６ cm ２ A substance having an electron mobility of 1 / Vs or more is preferred. Note that other substances can also be used as long as they have a higher electron transporting property than holes. Examples of electron-transporting materials that can be used include metal complexes having a quinoline skeleton, metal complexes having a benzoquinoline skeleton, metal complexes having an oxazole skeleton, and metal complexes having a thiazole skeleton, as well as oxadiazole derivatives, triazole derivatives, imidazole derivatives, oxazole derivatives, thiazole derivatives, phenanthroline derivatives, quinoline derivatives having a quinoline ligand, benzoquinoline derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, and other π-electron-deficient heteroaromatic compounds including nitrogen-containing heteroaromatic compounds.

[0273] 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).

[0274] The electron injection layer may be formed of, for example, lithium, cesium, lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF ２ ), 8-(quinolinolato)lithium (abbreviation: Liq), 2-(2-pyridyl)phenolatolithium (abbreviation: LiPP), 2-(2-pyridyl)-3-pyridinolatolithium (abbreviation: LiPPy), 4-phenyl-2-(2-pyridyl)phenolatolithium (abbreviation: LiPPP), lithium oxide (LiO ｘ ), alkali metals such as cesium carbonate, alkaline earth metals, or compounds thereof can be used.

[0275] Alternatively, the electron injection layer may be formed using a material having electron transport properties. For example, a compound having an unshared electron pair and an electron-deficient heteroaromatic ring may be used as the material having electron transport properties. Specifically, a compound having at least one of a pyridine ring, a diazine ring (pyrimidine ring, pyrazine ring, pyridazine ring), and a triazine ring may be used.

[0276] The organic compound having an unshared electron pair preferably has a lowest unoccupied molecular orbital (LUMO) of -3.6 eV to -2.3 eV. Generally, the highest occupied molecular orbital (HOMO) level and the LUMO level of an organic compound can be estimated by cyclic voltammetry (CV), photoelectron spectroscopy, optical absorption spectroscopy, inverse photoelectron spectroscopy, or the like.

[0277] For example, 4,7-diphenyl-1,10-phenanthroline (abbreviation: BPhen), 2,9-bis(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBPhen), diquinoxalino[2,3-a:2',3'-c]phenazine (abbreviation: HATNA), 2,4,6-tris[3'-(pyridin-3-yl)biphenyl-3-yl]-1,3,5-triazine (abbreviation: TmPPPyTz), etc. can be used as the organic compound having an unshared electron pair. Note that NBPhen has a higher glass transition temperature (Tg) and is superior in heat resistance compared to BPhen.

[0278] The light-emitting layer is a layer containing a light-emitting substance. The light-emitting layer can contain one or more light-emitting substances. As the light-emitting substance, a substance that emits light of a color such as blue, purple, blue-purple, green, yellow-green, yellow, orange, or red is appropriately used. Furthermore, a substance that emits near-infrared light can also be used as the light-emitting substance.

[0279] Examples of the light-emitting material include fluorescent materials, phosphorescent materials, TADF materials, and quantum dot materials.

[0280] 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.

[0281] 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.

[0282] The light-emitting layer may contain one or more organic compounds (host materials, assist materials, etc.) in addition to a light-emitting substance (guest material). 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.

[0283] The light-emitting layer preferably includes, for example, a phosphorescent material and a hole-transporting material and an electron-transporting material, which are a combination that easily forms an exciplex. This configuration allows efficient emission using Exciplex-Triple Energy Transfer (ExTET), which is energy transfer from the exciplex to the light-emitting material (phosphorescent material). By selecting a combination that forms an exciplex that emits light that overlaps with the wavelength of the lowest-energy absorption band of the light-emitting material, the energy transfer becomes smooth, allowing efficient emission. This configuration allows the light-emitting device to simultaneously achieve high efficiency, low-voltage operation, and a long life.

[0284] 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).

[0285] The formation of exciplexes can be confirmed, for example, by comparing the emission spectra of the hole-transporting material, the electron-transporting material, and a mixed film obtained by mixing these materials, and observing the phenomenon in which the emission spectrum of the mixed film is shifted to longer wavelengths than the emission spectra of each material (or has a new peak on the longer wavelength side). 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 a mixed film obtained by mixing these materials, and observing differences in transient response, such as the transient PL lifetime of the mixed film having a longer-lifetime component or a larger proportion of delayed components than the transient PL lifetimes of the individual materials. The above-mentioned transient PL may also be interpreted as transient electroluminescence (EL). That is, 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 a mixed film obtained by mixing these materials, and observing the differences in transient response.

[0286] The light-emitting layer 87R of the light-emitting element 61R contains a light-emitting organic compound that emits light having an intensity in at least the red wavelength range. The light-emitting layer 87G of the light-emitting element 61G contains a light-emitting organic compound that emits light having an intensity in at least the green wavelength range. The light-emitting layer 87B of the light-emitting element 61B contains a light-emitting organic compound that emits light having an intensity in at least the blue wavelength range. The light-emitting layer 87IR of the light-emitting element 61IR contains a light-emitting organic compound that emits light having an intensity in at least the infrared wavelength range. The light-receiving layer 90 of the light-receiving element 62 shown in FIG. 18A contains, for example, an organic compound that has detection sensitivity in the infrared wavelength range.

[0287] A conductive film that is translucent to visible light is used for either the pixel electrode 84 or the common electrode 81, and a conductive film that is reflective is used for the other. By making the pixel electrode 84 translucent and the common electrode 81 reflective, the display device 10 can be a bottom-emission type display device. On the other hand, by making the pixel electrode 84 reflective and the common electrode 81 translucent, the display device 10 can be a top-emission type display device. Note that by making both the pixel electrode 84 and the common electrode 81 translucent, the display device 10 can also be a dual-emission type display device.

[0288] Furthermore, the light-emitting element 61 preferably has a micro-optical resonator (microcavity) structure, which allows the light emitted from the light-emitting layer 87 to resonate between the pixel electrode 84 and the common electrode 81, thereby intensifying the light emitted from the light-emitting element 61.

[0289] When the light-emitting element 61 has a microcavity structure, it is preferable that one of the common electrode 81 or the pixel electrode 84 is an electrode that has both translucency and reflectivity (semi-transmissive / semi-reflective electrode), and the other of the common electrode 81 or the pixel electrode 84 is an electrode that has reflectivity (reflective electrode).

[0290] Alternatively, the light-emitting element 61 can have a microcavity structure by making the light-emitting layer 87IR of the light-emitting element 61IR that emits light with the longest wavelength the thickest, the light-emitting layer 87R of the light-emitting element 61R that emits light with the next longest wavelength the next thickest, the light-emitting layer 87G of the light-emitting element 61G that emits light with the next longest wavelength the next thickest, and the light-emitting layer 87B of the light-emitting element 61B that emits light with the shortest wavelength the thinnest. Note that this is not limiting, and the thickness of each light-emitting layer can be adjusted taking into consideration the wavelength of light emitted by each light-emitting element, the optical characteristics of the layers that make up the light-emitting element, the electrical characteristics of the light-emitting element, etc.

[0291] The light transmittance of the transparent electrode is 40% or more. For example, it is preferable to use an electrode for the light emitting element 61 that has a visible light (light with a wavelength of 400 nm or more and less than 750 nm) transmittance of 40% or more. 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. The resistivity of these electrodes is 1×10 −２ When a light-emitting element that emits near-infrared light is used in the display device, the transmittance and reflectance of these electrodes for near-infrared light (light with a wavelength of 750 nm or more and 1300 nm or less) are preferably in the above-mentioned ranges.

[0292] An insulating layer 92 is provided to cover the end portions of the pixel electrodes 84R, 84G, 84B, 84IR, and 84PD. The end portions of the insulating layer 92 are preferably tapered. Note that the insulating layer 92 need not be provided if it is not necessary.

[0293] For example, the hole injection layer 85R, the hole injection layer 85G, the hole injection layer 85B, the hole injection layer 85IR, and the hole transport layer 86PD each have a region in contact with the upper surface of the pixel electrode 84 and a region in contact with the surface of the insulating layer 92. In addition, an end of the hole injection layer 85R, an end of the hole injection layer 85G, an end of the hole injection layer 85B, an end of the hole injection layer 85IR, and an end of the hole transport layer 86PD are located on the insulating layer 92.

[0294] 20A , between light-emitting elements 61 emitting light of different colors, a gap is provided, for example, between two light-emitting layers 87. In this manner, it is preferable that light-emitting layer 87R, light-emitting layer 87G, and light-emitting layer 87B are provided so as not to be in contact with each other. This makes it possible to preferably prevent current from flowing through two adjacent light-emitting layers 87, thereby preventing unintended light emission. This can improve the contrast of the display device 10, thereby improving the display quality of the display device 10.

[0295] A protective layer 91 is provided on the common electrode 81. The protective layer 91 has a function of preventing impurities such as water from diffusing from above into each light-emitting element.

[0296] The protective layer 91 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 91 may be made of a semiconductor material such as indium gallium oxide or indium gallium zinc oxide.

[0297] 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.

[0298] Alternatively, a laminated film of an inorganic insulating film and an organic insulating film may be used as the protective layer 91. For example, a configuration in which an organic insulating film is sandwiched between a pair of inorganic insulating films is preferable. Furthermore, it is preferable that the organic insulating film functions as a planarizing film. This allows the upper surface of the organic insulating film to be flat, thereby improving the coverage of the inorganic insulating film thereon and enhancing the barrier properties. Furthermore, since the upper surface of the protective layer 91 is flat, when a structure (e.g., a color filter, a touch sensor electrode, a lens array, etc.) is provided above the protective layer 91, the influence of uneven shapes caused by the structure below can be reduced, which is preferable.

[0299] 20C shows an example of a cross-sectional configuration of the display device 10 in the Y direction shown in FIG. 18B etc., and specifically shows an example of a cross-sectional configuration of the light-emitting element 61R and the light-receiving element 62. Note that the light-emitting elements 61G, 61B, and 61IR can also be arranged in the Y direction in the same manner as the light-emitting element 61R.

[0300] 20D shows a connection portion 93 where the connection electrode 82 and the common electrode 81 are electrically connected. In the connection portion 93, the common electrode 81 is provided in contact with the connection electrode 82, and a protective layer 91 is provided to cover the common electrode 81. In addition, an insulating layer 92 is provided to cover the end of the connection electrode 82.

[0301] 20A to 20C show a structure in which the insulating layer 92 is provided to cover the end portions of the pixel electrodes 84R, 84G, 84B, and 84PD, but one embodiment of the present invention is not limited to this. As shown in FIG. 20E, the insulating layer 92 does not have to be provided.

[0302] Furthermore, an insulating layer may be provided in the region between adjacent light-emitting elements 61 and in the region between adjacent light-emitting elements 61 and light-receiving elements 62. Fig. 20E is a cross-sectional view corresponding to the dashed dotted line A1-A2 in Fig. 18B. In Fig. 20E, insulating layers 94 and 96 are provided in the regions.

[0303] The side surfaces of the pixel electrode 84R, pixel electrode 84G, pixel electrode 84B, hole injection layer 85R, hole injection layer 85G, hole injection layer 85B, hole transport layer 86R, hole transport layer 86G, hole transport layer 86B, light-emitting layer 87R, light-emitting layer 87G, light-emitting layer 87B, electron transport layer 88R, electron transport layer 88G, and electron transport layer 88B are covered with insulating layers 94 and 96, respectively. A common layer 89 is provided on the electron transport layer 88R, electron transport layer 88G, electron transport layer 88B, insulating layer 94, and insulating layer 96, and a common electrode 81 is provided on the common layer 89.

[0304] By adopting the above configuration, it is possible to prevent the common layer 89 (or the common electrode 81) from coming into contact with any of the sides of the pixel electrode 84R, the pixel electrode 84G, the pixel electrode 84B, the light-emitting layer 87R, the light-emitting layer 87G, and the light-emitting layer 87B, thereby preventing short circuits in the light-emitting elements.

[0305] The insulating layer 94 preferably covers at least the side surfaces of the pixel electrodes 84R, 84G, and 84B. Furthermore, the insulating layer 94 preferably covers the side surfaces of the hole injection layer 85R, 85G, and 85B, the hole transport layer 86R, the hole transport layer 86G, and 86B, the light-emitting layer 87R, the light-emitting layer 87G, and 87B, the electron transport layer 88R, the electron transport layer 88G, and the electron transport layer 88B. The insulating layer 94 can be configured to be in contact with each side surface of the pixel electrode 84R, the pixel electrode 84G, the pixel electrode 84B, the hole injection layer 85R, the hole injection layer 85G, the hole injection layer 85B, the hole transport layer 86R, the hole transport layer 86G, the hole transport layer 86B, the light-emitting layer 87R, the light-emitting layer 87G, the light-emitting layer 87B, the electron transport layer 88R, the electron transport layer 88G, and the electron transport layer 88B.

[0306] The insulating layer 96 is provided on the insulating layer 94 so as to fill recesses formed in the insulating layer 94. The insulating layer 96 can be configured to overlap with each side surface of the pixel electrode 84R, the pixel electrode 84G, the pixel electrode 84B, the hole injection layer 85R, the hole injection layer 85G, the hole injection layer 85B, the hole transport layer 86R, the hole transport layer 86G, the hole transport layer 86B, the light-emitting layer 87R, the light-emitting layer 87G, the light-emitting layer 87B, the electron transport layer 88R, the electron transport layer 88G, and the electron transport layer 88B, via the insulating layer 94.

[0307] Note that either the insulating layer 94 or the insulating layer 96 does not necessarily have to be provided. If the insulating layer 94 is not provided, the insulating layer 96 can be configured to be in contact with the side surfaces of each of the light-emitting layers 87R, 87G, and 87B. The display device may also have an insulating layer that covers the end portions of the pixel electrodes. In this case, one or both of the insulating layer 94 and the insulating layer 96 may be provided on the insulating layer.

[0308] The common layer 89 and the common electrode 81 are provided over the electron transport layer 88R, the electron transport layer 88G, the electron transport layer 88B, the insulating layer 94, and the insulating layer 96. Before the insulating layer 94 and the insulating layer 96 are provided, a step is generated between a region where the pixel electrode and the light-emitting layer are provided and a region where the pixel electrode and the light-emitting layer are not provided (a region between light-emitting elements). The display device of one embodiment of the present invention includes the insulating layer 94 and the insulating layer 96, which can flatten the step and improve the coverage of the common layer 89 and the common electrode 81. Therefore, poor connection due to a step can be suppressed. Alternatively, the step can be suppressed from locally thinning the common electrode 81, resulting in an increase in electrical resistance.

[0309] In order to improve the flatness of the surfaces on which the common layer 89 and the common electrode 81 are formed, it is preferable that the height of the upper surface of the insulating layer 94 and the upper surface of the insulating layer 96 be the same as or approximately the same as the height of the upper surface of at least one of the electron transport layers 88R, 88G, and 88B. The upper surface of the insulating layer 96 preferably has a flat shape, but may have protrusions or recesses.

[0310] The insulating layer 94 has an area in contact with the side surfaces of the light-emitting layers 87R, 87G, and 87B, and functions as a protective insulating layer for the light-emitting layers 87R, 87G, and 87B. Providing the insulating layer 94 can prevent impurities (oxygen, moisture, etc.) from entering the interior from the side surfaces of the light-emitting layers 87R, 87G, and 87B, thereby providing a highly reliable display device.

[0311] If the width (thickness) of the insulating layer 94 in the region in contact with the side surfaces of the light-emitting layers 87R, 87G, and 87B in a cross-sectional view is large, the spacing between the light-emitting layers 87R, 87G, and 87B will be large, which may result in a low aperture ratio. Also, if the width (thickness) of the insulating layer 94 in the region in contact with the side surfaces of the light-emitting layers 87R, 87G, and 87B in a cross-sectional view is small, the effect of suppressing impurities from penetrating into the interior from the side surfaces of the light-emitting layers 87R, 87G, and 87B may be reduced. In a cross-sectional view, the width (thickness) of insulating layer 94 in regions contacting the side surfaces of light-emitting layer 87R, light-emitting layer 87G, and light-emitting layer 87B is preferably 3 nm to 200 nm, more preferably 3 nm to 150 nm, even more preferably 5 nm to 150 nm, even more preferably 5 nm to 100 nm, even more preferably 10 nm to 100 nm, and even more preferably 10 nm to 50 nm. By setting the width (thickness) of insulating layer 94 within the above range, a display device having a high aperture ratio and high reliability can be obtained.

[0312] The insulating layer 94 may be an insulating layer containing an inorganic material. For example, inorganic insulating films such as an insulating oxide film, a nitride insulating film, an oxynitride insulating film, and a nitride oxide insulating film may be used for the insulating layer 94. The insulating layer 94 may have a single-layer structure or a multilayer structure. Examples of oxide insulating films include silicon oxide films, aluminum oxide films, magnesium oxide films, indium gallium zinc oxide films, gallium oxide films, germanium oxide films, yttrium oxide films, zirconium oxide films, lanthanum oxide films, neodymium oxide films, hafnium oxide films, and tantalum oxide films. Examples of nitride insulating films include silicon nitride films and aluminum nitride films. Examples of oxynitride insulating films include silicon oxynitride films and aluminum oxynitride films. Examples of nitride oxide insulating films include silicon nitride oxide films and aluminum nitride oxide films. Aluminum oxide is particularly preferable because it has a high etching selectivity with respect to the EL layer and functions to protect the EL layer during the formation of the insulating layer 96, which will be described later. 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 the ALD method as the insulating layer 94, it is possible to form an insulating layer 94 with few pinholes and excellent function of protecting the EL layer.

[0313] The insulating layer 94 can be formed by a sputtering method, a CVD method, a PLD method, an ALD method, etc. The insulating layer 94 is preferably formed by an ALD method, which has good coverage.

[0314] The insulating layer 96 provided on the insulating layer 94 serves to flatten recesses formed in the insulating layer 94 between adjacent light-emitting devices. In other words, the insulating layer 96 improves the flatness of the surface on which the common electrode 81 is formed. An insulating layer containing an organic material can be suitably used as the insulating layer 96. For example, the insulating layer 96 can be made of acrylic resin, polyimide resin, epoxy resin, imide resin, polyamide resin, polyimideamide resin, silicone resin, siloxane resin, benzocyclobutene-based resin, phenolic resin, or precursors of these resins. The insulating layer 96 can also be made of organic materials such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinylpyrrolidone, polyethylene glycol, polyglycerin, pullulan, water-soluble cellulose, or alcohol-soluble polyamide resin. The insulating layer 96 can also be made of a photosensitive resin (also referred to as an organic resin). Photoresist may be used as the photosensitive resin. The photosensitive resin can be a positive-tone material or a negative-tone material.

[0315] The difference in height between the upper surface of the insulating layer 96 and the upper surface of any one of the light-emitting layers 87R, 87G, and 87B is, for example, preferably 0.5 times or less, and more preferably 0.3 times or less, the thickness of the insulating layer 96. Alternatively, for example, the insulating layer 96 may be provided so that the upper surface of any one of the light-emitting layers 87R, 87G, and 87B is higher than the upper surface of the insulating layer 96. Alternatively, for example, the insulating layer 96 may be provided so that the upper surface of any one of the light-emitting layers 87R, 87G, and 87B is higher than the upper surface of the insulating layer 96.

[0316] 18A , 18B , 19A , and 19B , the pixel 80 includes a subpixel having a light-emitting element 61R, a subpixel having a light-emitting element 61G, a subpixel having a light-emitting element 61B, a subpixel having a light-emitting element 61IR, and a subpixel having a light-receiving element 62; however, one embodiment of the present invention is not limited to this. Display devices different from the display device 10 shown in FIG. 18A and the like are shown in FIGS. 21A to 23B .

[0317] The display device 10 shown in Fig. 21A differs from the display device 10 shown in Fig. 18A in that the pixel 80 is composed of a sub-pixel having a light-emitting element 61R, a sub-pixel having a light-emitting element 61G, a sub-pixel having a light-emitting element 61B, and a sub-pixel having a light-receiving element 62. In this case, the light-emitting element 61IR may be provided between the display region 95 and the connection electrode 82. Alternatively, as shown in Fig. 21B, the light-emitting element 61IR may be provided on the periphery of the display region 95 and the connection electrode 82. The area occupied by the light-receiving element 62 in the display device 10 can be made larger, thereby increasing the light detection sensitivity of the light-receiving element 62.

[0318] 21A , the light-emitting elements 61IR can be provided along the periphery of the display area 95. For example, they may be provided along one side of the periphery of the display area 95, or they may be provided across two or more sides of the periphery of the display area 95. That is, when the top surface of the display area 95 has a rectangular shape, the arrangement of the light-emitting elements 61IR in top view can be strip-shaped, L-shaped, U-shaped (square bracket-shaped), quadrangular, or the like.

[0319] 21B , the light-emitting elements 61IR can be provided along the outer periphery of the connection electrode 82. For example, the light-emitting elements 61IR may be provided along one side of the outer periphery of the connection electrode 82, or may be provided over two or more sides of the outer periphery of the connection electrode 82. In other words, when the top surface shape of the connection electrode 82 is rectangular, the arrangement of the light-emitting elements 61IR in top view can be strip-shaped, L-shaped, U-shaped (square bracket shaped), quadrangular, or the like.

[0320] 21A and 21B illustrate an example in which the Y-direction width of the light-emitting element 61IR is approximately the same as the Y-direction width of the pixel 80, but one embodiment of the present invention is not limited to this. The Y-direction width of the light-emitting element 61IR may be larger or smaller than the Y-direction width of the pixel 80. Also, FIGS. 21A and 21B illustrate an example in which the number of light-emitting elements 61IR in the Y direction is the same as the number of pixels 80, but one embodiment of the present invention is not limited to this. The number of light-emitting elements 61IR in the Y direction may be different from the number of pixels 80, and may be one or more. Also, FIGS. 21A and 21B illustrate an example in which one light-emitting element 61IR is provided in the X direction, but one embodiment of the present invention is not limited to this. The number of light-emitting elements 61IR in the X direction may be more than one.

[0321] The display device 10 shown in Fig. 22A differs from the display device 10 shown in Fig. 18A in that the pixel 80 is composed of a sub-pixel having a light-emitting element 61R, a sub-pixel having a light-emitting element 61G, a sub-pixel having a light-emitting element 61B, and a sub-pixel having a light-emitting element 61IR. In this case, the light-receiving element 62 may be provided between the display region 95 and the connection electrode 82. Alternatively, as shown in Fig. 22B, the light-receiving element 62 may be provided on the periphery of the display region 95 and the connection electrode 82. The area occupied by the light-receiving element 62 in the display device 10 can be made larger, thereby increasing the light detection sensitivity of the light-receiving element 62.

[0322] 22A , the light receiving elements 62 can be provided along the periphery of the display area 95. For example, the light receiving elements 62 can be provided along one side of the periphery of the display area 95, or can be provided across two or more sides of the periphery of the display area 95. That is, when the top surface of the display area 95 has a rectangular shape, the arrangement of the light receiving elements 62 in the top view can be strip-shaped, L-shaped, U-shaped (square bracket-shaped), quadrangular, or the like.

[0323] 22B , the light receiving elements 62 can be provided along the outer periphery of the connection electrode 82. For example, the light receiving elements 62 may be provided along one side of the outer periphery of the connection electrode 82, or may be provided over two or more sides of the outer periphery of the connection electrode 82. In other words, when the top surface shape of the connection electrode 82 is rectangular, the arrangement of the light receiving elements 62 in top view can be strip-shaped, L-shaped, U-shaped (square bracket-shaped), quadrangular, or the like.

[0324] 22A and 22B illustrate an example in which the width of the light receiving element 62 in the Y direction is approximately the same as the width of the pixel 80 in the Y direction, but this embodiment of the present invention is not limited to this. The width of the light receiving element 62 in the Y direction may be larger or smaller than the width of the pixel 80 in the Y direction. Also, FIGS. 22A and 22B illustrate an example in which the number of light receiving elements 62 in the Y direction is the same as the number of pixels 80, but this embodiment of the present invention is not limited to this. The number of light receiving elements 62 in the Y direction may be different from the number of pixels 80, and may be one or more. Also, FIGS. 22A and 22B illustrate an example in which one light receiving element 62 is provided in the X direction, but this embodiment of the present invention is not limited to this. The number of light receiving elements 62 in the X direction may be more than one.

[0325] The display device 10 shown in Fig. 23A differs from the display device 10 shown in Fig. 18A in that the pixel 80 is composed of a sub-pixel having a light-emitting element 61R, a sub-pixel having a light-emitting element 61G, and a sub-pixel having a light-emitting element 61B. In this case, the light-emitting element 61IR and the light-receiving element 62 may be provided between the display region 95 and the connection electrode 82. Alternatively, as shown in Fig. 23B, the light-emitting element 61IR and the light-receiving element 62 may be provided on the outer periphery of the display region 95 and the connection electrode 82. Since the lengths of the light-emitting elements 61R, 61G, and 61B in the Y direction can be increased, the brightness of the light emitted by the pixel 80 can be increased.

[0326] In the display device 10 shown in FIG. 23A , the light-emitting elements 61IR and the light-receiving elements 62 can be arranged along the periphery of the display area 95. For example, they may be arranged along one side of the periphery of the display area 95, or they may be arranged along two or more sides of the periphery of the display area 95. That is, when the top surface of the display area 95 is rectangular, the arrangement of the light-emitting elements 61IR and the light-receiving elements 62 in the top view can be strip-shaped, L-shaped, U-shaped (square bracket-shaped), square, or the like. Furthermore, the arrangement of the light-emitting elements 61IR and the light-receiving elements 62 may be different. For example, the light-emitting elements 61IR in the top view may be arranged on two opposing sides of the display area 95, and the light-receiving elements 62 in the top view may be arranged on two other sides.

[0327] In the display device 10 shown in FIG. 23B , the light-emitting elements 61IR and the light-receiving elements 62 can be arranged along the outer periphery of the connection electrode 82. For example, they may be arranged along one side of the outer periphery of the connection electrode 82, or they may be arranged along two or more sides of the outer periphery of the connection electrode 82. That is, when the top surface shape of the connection electrode 82 is rectangular, the arrangement of the light-emitting elements 61IR and the light-receiving elements 62 in the top view can be strip-shaped, L-shaped, U-shaped (square bracket-shaped), square, or the like. Furthermore, the arrangement of the light-emitting elements 61IR and the light-receiving elements 62 may be different. For example, the light-emitting elements 61IR in the top view may be arranged on two opposing sides of the connection electrode 82, and the light-receiving elements 62 in the top view may be arranged on two other sides.

[0328] 23A and 23B illustrate an example in which the sum of the Y-direction width of the light-emitting element 61IR and the Y-direction width of the light-receiving element 62 is approximately the same as the Y-direction width of the pixel 80, but this embodiment is not limited to this. The Y-direction widths of the light-emitting element 61IR and the light-receiving element 62 may be greater or smaller than the Y-direction width of the pixel 80. Also, while FIGS. 23A and 23B illustrate an example in which the number of light-emitting elements 61IR, the number of light-receiving elements 62, and the number of pixels 80 in the Y direction are the same, this embodiment is not limited to this. The number of light-emitting elements 61IR and the number of light-receiving elements 62 in the Y direction may be different from the number of pixels 80, and may be one or more. Also, the number of light-emitting elements 61IR and the number of light-receiving elements 62 in the Y direction may be different. 23A and 23B show an example in which one light-emitting element 61IR and one light-receiving element 62 are provided in the X direction, but one embodiment of the present invention is not limited thereto. The number of each of the light-emitting element 61IR and the light-receiving element 62 in the X direction may be plural.

[0329] 23A , the light-emitting element 61IR and the light-receiving element 62 are provided between the display region 95 and the connection electrode 82, and in FIG. 23B , the light-emitting element 61IR and the light-receiving element 62 are provided on the periphery of the display region 95 and the connection electrode 82, but one embodiment of the present invention is not limited to this. For example, the light-emitting element 61IR may be provided between the display region 95 and the connection electrode 82, and the light-receiving element 62 may be provided on the periphery of the display region 95 and the connection electrode 82. Alternatively, the light-receiving element 62 may be provided between the display region 95 and the connection electrode 82, and the light-emitting element 61IR may be provided on the periphery of the display region 95 and the connection electrode 82. This can be made larger than the area occupied by the light-receiving element 62 in the display device 10, thereby improving the light detection sensitivity of the light-receiving element 62.

[0330] Here, the display device 10 shown in each of Figures 21A and 21B corresponds to the display device 100 shown in Figure 3A. The display device 10 shown in each of Figures 22A and 22B corresponds to the display device 100 shown in Figure 6B. The display device 10 shown in each of Figures 23A and 23B corresponds to the display device 100 shown in Figure 6A.

[0331] Next, a configuration example of a display device included in an electronic device having an eye tracking function using visible light will be described with reference to FIGS. 24A to 25B. FIG.

[0332] The display device 10 shown in Figure 24A has multiple light-emitting elements 61R that emit red light, multiple light-emitting elements 61G that emit green light, multiple light-emitting elements 61B that emit blue light, multiple light-emitting elements 61LS that emit visible light, and multiple light-receiving elements 62.

[0333] 24A, in order to easily distinguish between the light-emitting elements 61, the light-emitting regions of the light-emitting elements 61 are labeled with R, G, B, and LS. The light-receiving regions of the light-receiving elements 62 are labeled with PD.

[0334] 24A corresponds to display device 100 in embodiment 1. Light-emitting element 61R, light-emitting element 61G, light-emitting element 61B, and light-emitting element 61LS correspond to light-emitting element 110R, light-emitting element 110G, light-emitting element 110B, and light-emitting element 110LS, respectively, in embodiment 1. Light-receiving element 62 corresponds to the light-receiving element of sensor unit 104 in embodiment 1.

[0335] The display device 10 shown in Fig. 24A differs from the display device 10 shown in Fig. 21A in that it has a light-emitting element 61LS instead of the light-emitting element 61IR. Other configurations are the same as those of the display device 10 shown in Fig. 21A, and therefore, for details, the description of Fig. 21A above can be referred to.

[0336] The light-emitting elements 61R, 61G, 61B, and light-receiving elements 62 are arranged in a matrix. FIG. 24A shows an example in which the light-emitting elements 61R, 61G, and 61B are arranged in the X direction, with the light-receiving elements 62 arranged below them. FIG. 24A also shows an example in which light-emitting elements 61 emitting light of the same color are arranged in the Y direction intersecting the X direction. In the display device 10 shown in FIG. 24A , a pixel 80 can be configured with, for example, sub-pixels having the light-emitting elements 61R, the sub-pixels having the light-emitting elements 61G, and the sub-pixels having the light-emitting elements 61B arranged in the X direction, and sub-pixels having the light-receiving elements 62 arranged below these sub-pixels. The light-receiving elements 62 shown in FIG. 24A have the function of detecting visible light.

[0337] In addition, in the display device 10 shown in FIG. 24A, the light-emitting element 61LS is provided between the display region 95 and the connection electrode 82.

[0338] 24A , the light-emitting elements 61LS can be provided along the outer periphery of the display region 95. For example, the light-emitting elements 61LS may be provided along one side of the outer periphery of the display region 95, or may be provided across two or more sides of the outer periphery of the display region 95. That is, when the top surface of the display region 95 has a rectangular shape, the arrangement of the light-emitting elements 61LS in top view can be a strip shape, an L-shape, a U-shape (square bracket shape), a square shape, or the like.

[0339] 24A illustrates an example in which the width of the light-emitting element 61LS in the Y direction is approximately the same as the width of the pixel 80 in the Y direction, but one embodiment of the present invention is not limited to this. The width of the light-emitting element 61LS in the Y direction may be larger or smaller than the width of the pixel 80 in the Y direction. FIG. 24A illustrates an example in which the number of light-emitting elements 61LS in the Y direction is the same as the number of pixels 80, but one embodiment of the present invention is not limited to this. The number of light-emitting elements 61LS in the Y direction may be different from the number of pixels 80, and may be one or more. FIG. 24A illustrates an example in which one light-emitting element 61LS is provided in the X direction, but one embodiment of the present invention is not limited to this. The number of light-emitting elements 61LS in the X direction may be more than one.

[0340] 24A , the light-emitting element 61LS is provided between the display region 95 and the connection electrode 82, but one embodiment of the present invention is not limited to this. The display device 10 shown in Fig. 24B differs from the display device 10 shown in Fig. 24A in that the light-emitting element 61LS is provided on the periphery of the display region 95 and the connection electrode 82.

[0341] 24B , the light-emitting elements 61LS can be provided along the outer periphery of the connection electrode 82. For example, the light-emitting elements 61LS may be provided along one side of the outer periphery of the connection electrode 82, or may be provided over two or more sides of the outer periphery of the connection electrode 82. In other words, when the top surface shape of the connection electrode 82 is rectangular, the arrangement of the light-emitting elements 61LS in top view can be strip-shaped, L-shaped, U-shaped (square bracket shaped), quadrangular, or the like.

[0342] Here, the display devices 10 shown in each of FIGS. 24A and 24B correspond to the display device 100 shown in FIG. 9B.

[0343] The cross-sectional view corresponding to the dashed dotted line A1-A2 in Fig. 24A is the same as the cross-sectional view shown in Fig. 20A. The cross-sectional view corresponding to the dashed dotted line C1-C2 in Fig. 24A is the same as the cross-sectional view shown in Fig. 20C. The cross-sectional view corresponding to the dashed dotted line D1-D2 in Fig. 24A is the same as the cross-sectional view shown in Fig. 20D. Note that the light-emitting element 61LS has a configuration similar to the light-emitting element 61R, light-emitting element 61G, or light-emitting element 61B, and therefore the description of the light-emitting element 61R, light-emitting element 61G, or light-emitting element 61B can be referred to.

[0344] The light receiving layer 90 of the light receiving element 62 shown in FIG. 24A includes an organic compound having detection sensitivity in the wavelength range of visible light, for example.

[0345] 24A and 24B, the pixel 80 includes a subpixel having a light-emitting element 61R, a subpixel having a light-emitting element 61G, a subpixel having a light-emitting element 61B, and a subpixel having a light-receiving element 62; however, one embodiment of the present invention is not limited to this. Display devices different from the display devices 10 shown in FIGS. 24A and 24B are shown in FIGS. 25A and 25B.

[0346] The display device 10 shown in Fig. 25A differs from the display device 10 shown in Fig. 24A in that the pixel 80 is composed of a sub-pixel having a light-emitting element 61R, a sub-pixel having a light-emitting element 61G, and a sub-pixel having a light-emitting element 61B. In this case, the light-emitting element 61LS and the light-receiving element 62 may be provided between the display region 95 and the connection electrode 82. Alternatively, as shown in Fig. 25B, the light-emitting element 61LS and the light-receiving element 62 may be provided on the outer periphery of the display region 95 and the connection electrode 82. Since the lengths of the light-emitting elements 61R, 61G, and 61B in the Y direction can be increased, the brightness of the light emitted by the pixel 80 can be increased.

[0347] In the display device 10 shown in FIG. 25A , the light-emitting elements 61LS and the light-receiving elements 62 can be arranged along the periphery of the display area 95. For example, they may be arranged along one side of the periphery of the display area 95, or they may be arranged along two or more sides of the periphery of the display area 95. That is, when the top surface of the display area 95 is rectangular, the arrangement of the light-emitting elements 61LS and the light-receiving elements 62 in the top view can be strip-shaped, L-shaped, U-shaped (square bracket-shaped), square, or the like. Furthermore, the arrangement of the light-emitting elements 61LS and the light-receiving elements 62 may be different. For example, the light-emitting elements 61LS in the top view may be arranged on two opposing sides of the display area 95, and the light-receiving elements 62 in the top view may be arranged on two other sides.

[0348] In the display device 10 shown in FIG. 25B , the light-emitting elements 61LS and the light-receiving elements 62 can be provided along the outer periphery of the connection electrode 82. For example, they may be provided along one side of the outer periphery of the connection electrode 82, or they may be provided along two or more sides of the outer periphery of the connection electrode 82. That is, when the top surface shape of the connection electrode 82 is rectangular, the arrangement of the light-emitting elements 61LS and the light-receiving elements 62 in the top view can be strip-shaped, L-shaped, U-shaped (square bracket-shaped), square, or the like. Furthermore, the arrangement of the light-emitting elements 61LS and the light-receiving elements 62 may be different. For example, the light-emitting elements 61LS in the top view may be arranged on two opposing sides of the connection electrode 82, and the light-receiving elements 62 in the top view may be arranged on two other sides.

[0349] 25A and 25B illustrate an example in which the sum of the Y-direction widths of the light-emitting elements 61LS and the Y-direction widths of the light-receiving elements 62 is approximately the same as the Y-direction width of the pixel 80, but this embodiment is not limited to this. The Y-direction widths of the light-emitting elements 61LS and the light-receiving elements 62 may be greater or smaller than the Y-direction width of the pixel 80. Also, while FIGS. 25A and 25B illustrate an example in which the number of light-emitting elements 61LS, the number of light-receiving elements 62, and the number of pixels 80 in the Y direction are the same, this embodiment is not limited to this. The number of light-emitting elements 61LS and the number of light-receiving elements 62 in the Y direction may be different from the number of pixels 80, and may be one or more. Also, the number of light-emitting elements 61LS and the number of light-receiving elements 62 in the Y direction may be different. 25A and 25B show an example in which one light-emitting element 61LS and one light-receiving element 62 are provided in the X direction, but one embodiment of the present invention is not limited thereto. The number of each of the light-emitting element 61LS and the light-receiving element 62 in the X direction may be plural.

[0350] 25A , the light-emitting element 61LS and the light-receiving element 62 are provided between the display region 95 and the connection electrode 82, and in FIG. 25B , the light-emitting element 61LS and the light-receiving element 62 are provided on the periphery of the display region 95 and the connection electrode 82, but one embodiment of the present invention is not limited to this. For example, the light-emitting element 61LS may be provided between the display region 95 and the connection electrode 82, and the light-receiving element 62 may be provided on the periphery of the display region 95 and the connection electrode 82. Alternatively, the light-receiving element 62 may be provided between the display region 95 and the connection electrode 82, and the light-emitting element 61LS may be provided on the periphery of the display region 95 and the connection electrode 82. This can be made larger than the area occupied by the light-receiving element 62 in the display device 10, thereby improving the light detection sensitivity of the light-receiving element 62.

[0351] Here, the display devices 10 shown in each of FIGS. 25A and 25B correspond to the display device 100 shown in FIG. 11B.

[0352] 26A , the light-emitting element has an EL layer 686 between a pair of electrodes (electrode 672 and electrode 688). The EL layer 686 can be formed of a plurality of layers such as a layer 4420, a light-emitting layer 4411, and a layer 4430. The layer 4420 can have, for example, a layer containing a substance with high electron-injection properties (electron-injection layer) and a layer containing a substance with high electron-transport properties (electron-transport layer). The light-emitting layer 4411 contains, for example, a light-emitting compound. The layer 4430 can have, for example, a layer containing a substance with high hole-injection properties (hole-injection layer) and a layer containing a substance with high hole-transport properties (hole-transport layer).

[0353] A structure including the layer 4420, the light-emitting layer 4411, and the layer 4430 provided between a pair of electrodes can function as a single light-emitting unit, and the structure of FIG. 26A is referred to as a single structure in this specification.

[0354] 26B shows a modified example of an EL layer 686 included in the light-emitting element shown in Fig. 26A. Specifically, the light-emitting element shown in Fig. 26B includes a layer 4430-1 on an electrode 672, a layer 4430-2 on the layer 4430-1, a light-emitting layer 4411 on the layer 4430-2, a layer 4420-1 on the light-emitting layer 4411, a layer 4420-2 on the layer 4420-1, and an electrode 688 on the layer 4420-2. For example, when the electrode 672 is an anode and the electrode 688 is a cathode, the layer 4430-1 functions as a hole-injection layer, the layer 4430-2 functions as a hole-transport layer, the layer 4420-1 functions as an electron-transport layer, and the layer 4420-2 functions as an electron-injection layer. Alternatively, when the electrode 672 is a cathode and the electrode 688 is an anode, the layer 4430-1 functions as an electron injection layer, the layer 4430-2 functions as an electron transport layer, the layer 4420-1 functions as a hole transport layer, and the layer 4420-2 functions as a hole injection layer. With such a layer structure, carriers can be efficiently injected into the light-emitting layer 4411, and the efficiency of carrier recombination in the light-emitting layer 4411 can be increased.

[0355] Note that a configuration in which a plurality of light-emitting layers (light-emitting layer 4411, light-emitting layer 4412, light-emitting layer 4413) are provided between the layer 4420 and the layer 4430 as shown in FIG. 26C is also a variation of the single structure.

[0356] 26D, a configuration in which a plurality of light-emitting units (EL layer 686a, EL layer 686b) are connected in series via an intermediate layer (charge generating layer) 4440 is referred to as a tandem structure in this specification. Note that although the configuration shown in FIG. 26D is referred to as a tandem structure in this specification and the like, this is not limiting, and for example, the tandem structure may also be referred to as a stack structure. Note that by using a tandem structure, a light-emitting element capable of emitting light with high brightness can be obtained.

[0357] 26C and 26D, the layer 4420 and the layer 4430 may have a laminated structure consisting of two or more layers, as shown in FIG. 26B.

[0358] The light-emitting color of the light-emitting element can be red, green, blue, cyan, magenta, yellow, white, or the like, depending on the material constituting the EL layer 686. Furthermore, the color purity can be further improved by providing the light-emitting element with a microcavity structure.

[0359] A light-emitting element that emits white light preferably has a structure in which two or more types of light-emitting materials are contained in the light-emitting layer. To obtain white light emission, light-emitting materials may be selected such that the respective emissions of the two or more light-emitting materials have 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 to each other, a light-emitting element that emits white light as a whole can be obtained. The same applies to a light-emitting element having three or more light-emitting layers.

[0360] The light-emitting layer preferably contains two or more light-emitting materials that emit light of R (red), G (green), B (blue), Y (yellow), O (orange), etc. Alternatively, it is preferable that the light-emitting layer contains two or more light-emitting materials, and the light emitted by each of the light-emitting materials contains spectral components of two or more colors of R, G, and B.

[0361] <Configuration Example of Light-Emitting Element and Light-Receiving Element> A display device according to one embodiment of the present invention is a top-emission type that emits light in a direction opposite to a substrate on which a light-emitting element is formed. In this embodiment, a display device including a top-emission light-emitting element and a light-receiving element will be described as an example.

[0362] In this specification and the like, 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.

[0363] The display device 380A shown in Figure 27 has 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, a light emitting element 370B that emits blue (B) light, and a light emitting element 370IR that emits infrared light (IR).

[0364] 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. The light-emitting element 370R has a light-emitting layer 383R, the light-emitting element 370G has a light-emitting layer 383G, the light-emitting element 370B has a light-emitting layer 383B, and the light-emitting element 370IR has a light-emitting layer 383IR. The light-emitting layer 383R contains a light-emitting material that emits red light, the light-emitting layer 383G contains a light-emitting material that emits green light, the light-emitting layer 383B contains a light-emitting material that emits blue light, and the light-emitting layer 383IR contains a light-emitting material that emits infrared light.

[0365] 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 .

[0366] 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.

[0367] 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.

[0368] 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, the light-receiving element is driven by applying a reverse bias between the pixel electrode 371 and the common electrode 375, so that the light incident on the light-receiving element can be detected, an electric charge can be generated, and the electric charge can be extracted as a current.

[0369] 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.

[0370] The display device 380A shows an example in which 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.

[0371] A conductive film that transmits visible light is used for the electrode from which light is extracted, either the pixel electrode 371 or 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.

[0372] 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.

[0373] 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. The resistivity of these electrodes is 1×10 −２ When the light-emitting element emits near-infrared light (light having 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.

[0374] 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 with high hole-injection properties, a substance with high hole-transport properties, a hole-blocking material, a substance with high electron-transport properties, a substance with high electron-injection properties, an electron-blocking material, a bipolar substance (a substance with high electron-transport properties and high hole-transport properties), or the like.

[0375] 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.

[0376] 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, and the electron transport layer is a layer that transports electrons generated in the active layer based on incident light to the cathode.

[0377] Note that for the hole injection layer, the hole transport layer, the electron transport layer, the electron injection layer, and the light-emitting layer, the contents described in <Top view and cross-sectional view of the light-emitting element and its periphery> can be referred to.

[0378] 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 deposition), which is preferable because a common manufacturing device can be used.

[0379] The active layer 373 has an n-type semiconductor material, such as fullerene (e.g., C ６０ , C ７０ Examples of electron-accepting organic semiconductor materials include fullerene derivatives and the like. Fullerenes have a soccer ball-like shape, and this shape 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 π-electron conjugation (resonance) spreads on a plane, as in benzene, electron-donating (donor) properties increase, but fullerenes have a spherical shape, so they have high electron-accepting properties despite the wide spread of π-electrons. High electron-accepting properties cause charge separation 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, and C ７０ is C ６０ Other fullerene derivatives include [6,6]-Phenyl-C71-butylic acid methyl ester (abbreviation: PC70BM), [6,6]-Phenyl-C61-butylic acid methyl ester (abbreviation: PC60BM), and 1',1",4',4"-Tetrahydro-di[1,4]methanenaphthaleno[1,2:2',3',56,60:2",3"][5,6]fullerene-C60 (abbreviation: ICBA).

[0380] 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.

[0381] 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), and quinacridone.

[0382] Examples of p-type semiconductor materials include carbazole derivatives, thiophene derivatives, furan derivatives, compounds having an aromatic amine skeleton, etc. Examples of p-type semiconductor materials include naphthalene derivatives, anthracene derivatives, pyrene derivatives, triphenylene derivatives, fluorene derivatives, pyrrole derivatives, benzofuran derivatives, benzothiophene derivatives, indole derivatives, dibenzofuran derivatives, dibenzothiophene derivatives, indolocarbazole derivatives, porphyrin derivatives, phthalocyanine derivatives, naphthalocyanine derivatives, quinacridone derivatives, polyphenylenevinylene derivatives, polyparaphenylene derivatives, polyfluorene derivatives, polyvinylcarbazole derivatives, polythiophene derivatives, etc.

[0383] 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.

[0384] 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.

[0385] For example, the active layer 373 is preferably formed by co-evaporating an n-type semiconductor and a p-type semiconductor, or may be formed by laminating an n-type semiconductor and a p-type semiconductor.

[0386] 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 a vapor deposition method (including a vacuum vapor deposition method), a transfer method, a printing method, an inkjet method, or a coating method.

[0387] For example, a polymer compound such as poly(3,4-ethylenedioxythiophene) / poly(styrenesulfonic acid) (PEDOT / PSS) can be used as the hole transport material, and an inorganic compound such as molybdenum oxide or copper iodide (CuI) can be used as the electron transport material.

[0388] 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 (abbreviation: 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.

[0389] Furthermore, three or more types of materials may be mixed in the active layer 373. For example, in order to expand the wavelength range, a third material may be mixed in addition to an n-type semiconductor material and a p-type semiconductor material. In this case, the third material may be a low molecular weight compound or a high molecular weight compound.

[0390] The display device 380B shown in Figure 28A has 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.

[0391] The display device 380B shown in Fig. 28A differs from the display device 380A shown in Fig. 27 in that it does not have a light-emitting element 370IR that emits infrared light (IR). Since the other configurations are the same as those of the display device 380A, the description of Fig. 27 above can be referred to for details.

[0392] A display device 380C shown in FIG. 28B differs from display device 380B in that a light receiving element 370PD and a light emitting element 370R have the same configuration.

[0393] The light receiving element 370PD and the light emitting element 370R have in common an active layer 373 and a light emitting layer 383R.

[0394] Here, it is preferable that the 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, the light receiving element 370PD configured to detect blue light can have the same configuration as one or both of the light emitting element 370R and the light emitting element 370G. For example, the light receiving element 370PD configured to detect green light can have the same configuration as the light emitting element 370R.

[0395] 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.

[0396] 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 the pixel aperture ratio to be increased, and the light extraction efficiency of the display device to be improved. This also allows the life of the light emitting element to be extended. Furthermore, the display device can display high brightness. Furthermore, it is possible to increase the resolution of the display device.

[0397] The light-emitting layer 383R includes a light-emitting material that emits red light. The 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). The active layer 373 preferably includes an organic compound that does not easily absorb red light and that absorbs light with a wavelength shorter than red. This allows the light-emitting element 370R to efficiently extract red light, and the light-receiving element 370PD to detect light with a wavelength shorter than red with high accuracy.

[0398] Furthermore, in the display device 380C, 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.

[0399] 29A and 29B includes a light receiving / emitting element 370SR, a light emitting element 370G, and a light emitting element 370B that emit red (R) light and have a light receiving function. 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.

[0400] The light emitting / receiving element 370SR has 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 stacked in this order. 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 380C.

[0401] 29A shows a case where the light emitting / receiving element 370SR functions as a light emitting element. In FIG. 29A, 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.

[0402] 29B shows a case where the light receiving / emitting element 370SR functions as a light receiving element, in which 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.

[0403] 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.

[0404] 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 process for 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 impart one or both of an imaging function and a sensing function to the display area without significantly increasing the manufacturing process.

[0405] There are no limitations on the stacking order of the light-emitting layer 383R and the active layer 373. Figures 29A and 29B 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.

[0406] 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. Furthermore, the light emitting / receiving element may have other functional layers such as a hole blocking layer and an electron blocking layer.

[0407] 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.

[0408] 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.

[0409] 29C to 29G show examples of the stacked structure of the light emitting and receiving element.

[0410] The light emitting / receiving element shown in FIG. 29C has 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 .

[0411] FIG. 29C shows an example in which a light-emitting layer 383R is provided on a hole-transporting layer 382, ​​and an active layer 373 is stacked on the light-emitting layer 383R.

[0412] As shown in Figures 29A to 29C, the active layer 373 and the light-emitting layer 383R may be in contact with each other.

[0413] 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, at least one layer selected from a hole-injection layer, a hole-transport layer, an electron-transport layer, an electron-injection layer, a hole-blocking layer, and an electron-blocking layer can be used as the buffer layer. Figure 29D shows an example in which a hole-transporting layer 382 is used as the buffer layer.

[0414] 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. The buffer layer can also 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 achieve high light-emitting efficiency.

[0415] 29E 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 a light-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 382-2 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 382-2. Alternatively, the positions of the active layer 373 and the light-emitting layer 383R may be interchanged.

[0416] 29F differs from the light-emitting / receiving element shown in Fig. 29A 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 and an electron blocking layer.

[0417] The light emitting / receiving device shown in FIG. 29G differs from the light emitting / receiving device shown in FIG. 29A 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.

[0418] As a layer that serves as both a light-emitting layer and an active layer, for example, a layer containing three materials, namely, 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, can be used.

[0419] 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.

[0420] 30 is a cross-sectional view showing a configuration example of a display device 10. The display device 10 has a stacked structure of a transistor 310 having a channel formed in a substrate 301 and a transistor 320 having a channel formed in a semiconductor layer containing metal oxide.

[0421] An insulating layer 261 is provided to cover the transistor 310, and a conductive layer 251 is provided over the insulating layer 261. An insulating layer 262 is provided to cover the conductive layer 251, and a conductive layer 252 is provided over the insulating layer 262. The conductive layers 251 and 252 each function as wirings. An insulating layer 263 and an insulating layer 332 are provided to cover the conductive layer 252, and the transistor 320 is provided over the insulating layer 332. An insulating layer 265 is provided to cover the transistor 320, and a capacitor 240 is provided over the insulating layer 265. The capacitor 240 and the transistor 320 are electrically connected by a plug 274.

[0422] The transistor 320 can be used as a transistor that forms a pixel circuit or a transistor that forms a memory cell. The transistor 310 can be used as a transistor that forms a memory cell, a transistor that forms a driver circuit for driving the pixel circuit, or a transistor that forms an arithmetic circuit. The transistors 310 and 320 can be used as transistors that form various circuits such as an arithmetic circuit or a memory circuit.

[0423] The transistor 310 has a channel formation region in a substrate 301. The substrate 301 can be, for example, a semiconductor substrate such as a single crystal silicon substrate. The transistor 310 includes a part of the substrate 301, a conductive layer 311, a pair of low-resistance regions 312, an insulating layer 313, and an insulating layer 314. The conductive layer 311 functions as a gate electrode. The insulating layer 313 is located between the substrate 301 and the conductive layer 311 and functions as a gate insulating layer. The pair of low-resistance regions 312 are regions in which the substrate 301 is doped with impurities and function as one of a source and a drain. The insulating layer 314 is provided to cover side surfaces of the conductive layer 311 and functions as an insulating layer.

[0424] Furthermore, an element isolation layer 315 is provided between two adjacent transistors 310 so as to be embedded in the substrate 301 .

[0425] The transistor 320 is a transistor in which a metal oxide (also referred to as an oxide semiconductor) is used for a semiconductor layer in which a channel is formed.

[0426] The transistor 320 includes a semiconductor layer 321 , an insulating layer 323 , a conductive layer 324 , a pair of conductive layers 325 , an insulating layer 326 , and a conductive layer 327 .

[0427] The insulating layer 332 functions as a barrier layer that prevents impurities such as water or hydrogen from diffusing from the substrate 301 side to the transistor 320 and prevents oxygen from being released from the semiconductor layer 321 toward the insulating layer 332. As the insulating layer 332, for example, a film through which hydrogen or oxygen is less likely to diffuse than a silicon oxide film, such as an aluminum oxide film, a hafnium oxide film, or a silicon nitride film, can be used.

[0428] A conductive layer 327 is provided over the insulating layer 332, and an insulating layer 326 is provided to cover the conductive layer 327. The conductive layer 327 functions as a first gate electrode of the transistor 320, and part of the insulating layer 326 functions as a first gate insulating layer. An oxide insulating film such as a silicon oxide film is preferably used for at least a portion of the insulating layer 326 that is in contact with the semiconductor layer 321. The top surface of the insulating layer 326 is preferably planarized.

[0429] The conductive layer 327 may be a single layer or a stack of two or more conductive layers. When the conductive layer 327 has a structure in which two conductive layers are stacked, the conductive layer in contact with the bottom and sidewall of the opening in the insulating layer 326 is preferably made of a conductive material that has a function of suppressing the diffusion of impurities such as water or hydrogen or oxygen. Examples of such conductive materials include titanium, titanium nitride, tantalum, tantalum nitride, ruthenium, and ruthenium oxide. This structure can suppress the diffusion of impurities such as water or hydrogen into the semiconductor layer 321.

[0430] A single layer or a stack of two or more inorganic insulating films may be used as the insulating layer 326. When a stack of two or more inorganic insulating films is used as the insulating layer 326, one of the inorganic insulating films included in the insulating layer 326 preferably functions as a barrier layer that prevents impurities such as water or hydrogen from diffusing from the substrate 301 side to the transistor 320. As the inorganic insulating film, an insulating film similar to the insulating layer 328 can be used.

[0431] The semiconductor layer 321 is provided over the insulating layer 326. The semiconductor layer 321 preferably includes a metal oxide (also referred to as an oxide semiconductor) film having semiconductor properties. The semiconductor layer 321 preferably includes a metal oxide containing at least one of indium, an element M (the element M is aluminum, gallium, yttrium, or tin), and zinc. An OS transistor using such a metal oxide for a channel formation region has a characteristic of extremely low off-state current. Therefore, an OS transistor is preferably used as a transistor provided in a pixel circuit because analog data written to the pixel circuit can be retained for a long period of time. Similarly, an OS transistor is preferably used as a transistor used in a memory cell because analog data written to the memory cell can be retained for a long period of time.

[0432] The pair of conductive layers 325 are provided over and in contact with the semiconductor layer 321 and function as a source electrode and a drain electrode.

[0433] An insulating layer 328 is provided to cover top surfaces and side surfaces of the pair of conductive layers 325 and side surfaces of the semiconductor layer 321, and an insulating layer 264 is provided over the insulating layer 328. The insulating layer 328 functions as a barrier layer that prevents impurities such as water or hydrogen from diffusing from the insulating layer 264 or the like to the semiconductor layer 321 and prevents oxygen from being released from the semiconductor layer 321. The insulating layer 328 can be an insulating film similar to the insulating layer 332.

[0434] Openings reaching the semiconductor layer 321 are provided in the insulating layer 328 and the insulating layer 264. Inside the openings, an insulating layer 323 and a conductive layer 324 are buried, which are in contact with side surfaces of the insulating layer 264, the insulating layer 328, and the conductive layer 325 and an upper surface of the semiconductor layer 321. The conductive layer 324 functions as a second gate electrode, and the insulating layer 323 functions as a second gate insulating layer.

[0435] The insulating layer 323 can be, for example, an inorganic insulating film such as a silicon oxide film or a silicon oxynitride film. Note that the insulating layer 323 is not limited to a single-layer inorganic insulating film and may be a stack of two or more inorganic insulating films. For example, an aluminum oxide film, a hafnium oxide film, a silicon nitride film, or the like may be provided as a single layer or a stack on the side in contact with the conductive layer 324. This can suppress oxidation of the conductive layer 324. Furthermore, for example, an aluminum oxide film or a hafnium oxide film may be provided on the side in contact with the insulating layer 264, the insulating layer 328, and the conductive layer 325. This can suppress desorption of oxygen from the semiconductor layer 321, excessive supply of oxygen to the semiconductor layer 321, oxidation of the conductive layer 325, and the like.

[0436] The upper surfaces of the conductive layer 324, the insulating layer 323, and the insulating layer 264 are planarized so that their heights are approximately the same, and insulating layers 329 and 265 are provided to cover them.

[0437] Note that the conductive layer 327 and the conductive layer 324 preferably overlap with each other through an insulator on the outer side of the side surface in the channel width direction of the semiconductor layer 321. With this structure, the channel formation region of the semiconductor layer 321 can be electrically surrounded by the electric field of the conductive layer 327 functioning as the first gate electrode and the electric field of the conductive layer 324 functioning as the second gate electrode. In this specification, a transistor structure in which the channel formation region is electrically surrounded by the electric fields of the first gate electrode and the second gate electrode is referred to as a surrounded channel (S-channel) structure.

[0438] In this specification and the like, a transistor with an S-channel structure refers to a transistor structure in which a channel formation region is electrically surrounded by the electric fields of one and the other of a pair of gate electrodes. The S-channel structure disclosed in this specification and the like is different from a fin structure and a planar structure. By adopting the S-channel structure, it is possible to improve resistance to the short channel effect, in other words, to make the transistor less susceptible to the short channel effect.

[0439] By configuring the transistor 320 as a normally-off transistor and having the above-described S-channel structure, the channel formation region can be electrically surrounded. Therefore, the transistor 320 can also be regarded as having a Gate All Around (GAA) structure or a Lateral Gate All Around (LGAA) structure. By configuring the transistor 320 as an S-channel structure, a GAA structure, or an LGAA structure, the channel formation region formed at or near the interface between the semiconductor layer 321 and the gate insulating film can be the entire bulk of the semiconductor layer 321. Therefore, the current density flowing through the transistor can be improved, which is expected to improve the on-state current of the transistor or the field-effect mobility of the transistor.

[0440] The insulating layer 264 and the insulating layer 265 function as interlayer insulating layers. The insulating layer 329 functions as a barrier layer that prevents impurities such as water or hydrogen from diffusing from the insulating layer 265 or the like to the transistor 320. The insulating layer 329 can be formed using an insulating film similar to the insulating layer 328 and the insulating layer 332.

[0441] The plug 274 electrically connected to one of the pair of conductive layers 325 is provided so as to be embedded in the insulating layer 265, the insulating layer 329, and the insulating layer 264. The plug 274 has a structure in which the conductive layer is provided as a single layer or a stacked structure of two or more layers. When the plug 274 has a structure in which two conductive layers are stacked, it is preferable to use a conductive material through which hydrogen and oxygen do not easily diffuse as the conductive layer covering the side surfaces of the openings of the insulating layer 265, the insulating layer 329, the insulating layer 264, and the insulating layer 328 and part of the top surface of the conductive layer 325. This structure can prevent impurities such as water or hydrogen from the insulating layer 264 or the like from being mixed into the semiconductor layer 321 through the plug 274. Furthermore, it can prevent oxygen contained in the insulating layer 264 from being absorbed by the plug 274.

[0442] Furthermore, an insulating layer 275 is provided in contact with the side surface of the plug 274. That is, a configuration may be adopted in which the insulating layer 275 is provided in contact with the insulating layer 265, the insulating layer 329, and the inner wall of the opening of the insulating layer 264, and the plug 274 is provided in contact with the side surface of the insulating layer 275 and part of the upper surface of the conductive layer 325. Note that there may be cases in which the insulating layer 275 does not need to be provided.

[0443] The capacitor 240 has a conductive layer 241, a conductive layer 245, and an insulating layer 243 located therebetween. The conductive layer 241 functions as one electrode of the capacitor 240, the conductive layer 245 functions as the other electrode of the capacitor 240, and the insulating layer 243 functions as a dielectric of the capacitor 240.

[0444] The conductive layer 241 is provided over the insulating layer 265 and is buried in the insulating layer 254. The conductive layer 241 is electrically connected to one of the source and the drain of the transistor 310 by a plug 271 buried in the insulating layer 261. The insulating layer 243 is provided to cover the conductive layer 241. The conductive layer 245 is provided in a region overlapping with the conductive layer 241 with the insulating layer 243 interposed therebetween.

[0445] An insulating layer 255 is provided to cover the capacitor 240, and a light-emitting element 61, a light-receiving element 62, and the like are provided on the insulating layer 255. A protective layer 91 is provided on the light-emitting element 61 and the light-receiving element 62, and a substrate 420 is attached to the upper surface of the protective layer 91 with a resin layer 419. A light-transmitting substrate can be used as the substrate 420.

[0446] The pixel electrode 84 of the light-emitting element 61 and the pixel electrode 84PD of the light-receiving element 62 are electrically connected to either the source or drain of the transistor 310 by a plug 256 embedded in the insulating layer 255, a conductive layer 241 embedded in the insulating layer 254, and a plug 271 embedded in the insulating layer 261.

[0447] With this configuration, OS transistors that constitute pixel circuits and memory cells can be arranged directly below the light-receiving elements and light-emitting elements, and driver circuits, arithmetic circuits, etc. can also be arranged, making it possible to miniaturize a display device with high performance.

[0448] 30 illustrates a configuration in which the display device 10 includes a stack of a transistor 310 and a transistor 320. The configuration of the display device 10 is not limited to this, and the display device 10 may include the transistor 310 but not the transistor 320, may include the transistor 320 but not the transistor 310, may have a configuration in which multiple transistors 320 are stacked, or may have a configuration in which the transistor 310 and multiple transistors 320 are stacked over the transistor 310.

[0449] Furthermore, when a silicon substrate is used as the substrate 301, a photodiode having a photoelectric conversion layer formed thereon may be formed on the silicon substrate, and the photodiode may be used as the light-receiving element of the sensor portion 104 described in Embodiment 1. In other words, the light-receiving element of the sensor portion 104 described in Embodiment 1 may be formed on the silicon substrate. In this case, the transistor 310 may or may not be formed.

[0450] At least a part of the configuration examples exemplified in this embodiment and the corresponding drawings can be appropriately combined with other configuration examples or drawings.

[0451] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0452] <Additional Notes Regarding the Description of the Present Specification, etc.> The following additional notes will be given regarding the above-described embodiments and the explanations of the respective configurations in the embodiments.

[0453] The configurations shown in each embodiment can be combined with the configurations shown in other embodiments as appropriate to form one aspect of the present invention. In addition, when multiple configuration examples are shown in one embodiment, the configuration examples can be combined as appropriate.

[0454] In addition, the content (or even a part of the content) described in one embodiment can be applied to, combined with, or replaced with another content (or even a part of the content) described in that embodiment, and / or the content (or even a part of the content) described in one or more other embodiments.

[0455] The contents described in the embodiments refer to the contents described in each embodiment using various figures or the contents described using text in the specification.

[0456] Furthermore, a figure (or a portion thereof) described in one embodiment can be combined with another portion of that figure, another figure (or a portion thereof) described in that embodiment, and / or a figure (or a portion thereof) described in one or more other embodiments to form even more figures.

[0457] In addition, in the present specification and the like, in the block diagrams, components are classified by function and shown as independent blocks. However, in actual circuits, etc., it is difficult to separate components by function, and there may be cases where one circuit is involved in multiple functions, or where one function is involved across multiple circuits. Therefore, the blocks in the block diagrams are not limited to the components described in the specification, but may be rephrased appropriately depending on the situation.

[0458] In addition, in the drawings, the size, layer thickness, or region is shown at an arbitrary size for convenience of explanation. Therefore, it is not necessarily limited to the scale. Note that the drawings are shown schematically for clarity, and are not limited to the shapes or values ​​shown in the drawings. For example, it is possible to include variations in signal, voltage, or current due to noise, or variations in signal, voltage, or current due to timing deviations.

[0459] In this specification and the like, when describing the connection relationship of a transistor, the terms "one of the source or drain" (or first electrode or first terminal) and "the other of the source or drain" (or second electrode or second terminal) are used. This is because the source and drain of a transistor vary depending on the structure or operating conditions of the transistor. Note that the source and drain of a transistor can be appropriately referred to as source (drain) terminal, source (drain) electrode, or the like depending on the situation.

[0460] Furthermore, the terms "electrode" and "wiring" used in this specification and the like do not limit the functionality of these components. For example, an "electrode" may be used as part of a "wiring," and vice versa. Furthermore, the terms "electrode" and "wiring" also include cases where multiple "electrodes" or "wirings" are integrally formed.

[0461] Furthermore, in this specification and the like, the terms voltage and potential can be interchanged as appropriate. Voltage refers to the potential difference from a reference potential. For example, if the reference potential is a ground voltage (earth voltage), then voltage can be interchanged with potential. Ground potential does not necessarily mean 0 V. Note that potential is relative, and the potential applied to wiring, etc. may change depending on the reference potential.

[0462] In this specification and the like, terms such as "film" and "layer" can be interchangeable depending on the circumstances. For example, the term "conductive layer" can be changed to the term "conductive film." Or, for example, the term "insulating film" can be changed to the term "insulating layer."

[0463] In this specification, a switch refers to a device that has a function of controlling whether a current flows by being in a conductive state (on state) or a non-conductive state (off state), or a device that has a function of selecting and switching a path for a current to flow.

[0464] In this specification, the channel length refers to, for example, in a top view of a transistor, a region where a semiconductor (or a portion in the semiconductor through which current flows when the transistor is on) and a gate overlap, or a distance between a source and a drain in a region where a channel is formed.

[0465] In this specification, the channel width refers to, for example, the length of the region where the semiconductor (or the portion in the semiconductor through which current flows when the transistor is on) and the gate electrode overlap, or the length of the portion where the source and drain face each other in the region where the channel is formed.

[0466] In this specification, "A and B are connected" includes not only a direct connection between A and B, but also an electrical connection between A and B. Here, "A and B are electrically connected" means that when an object having some kind of electrical effect exists between A and B, transmission of an electrical signal between A and B is possible.

[0467] In this specification, an element fabricated using a metal mask or FMM may be referred to as an element with an MM (metal mask) structure. Also, in this specification, an element fabricated without using a metal mask or FMM may be referred to as an element with an MML (metal maskless) structure.

[0468] In this specification and the like, a structure in which different light-emitting layers are formed for light-emitting elements of each color (here, blue (B), green (G), and red (R)), or in which different light-emitting layers are painted, may be referred to as an SBS (Side By Side) structure. In this specification and the like, a light-emitting element that can emit white light may be referred to as a white light-emitting element. In addition, a white light-emitting element can be made into a light-emitting element that displays full color by combining it with a colored layer (for example, a color filter).

[0469] Furthermore, light-emitting elements can be broadly divided into single structures and tandem structures. A single-structure element preferably has one light-emitting unit between a pair of electrodes, and the light-emitting unit includes one or more light-emitting layers. When two light-emitting layers are used to obtain white light emission, light-emitting layers may be selected such that the emission colors of the two light-emitting layers are complementary to each other. For example, by making the emission color of the first light-emitting layer and the emission color of the second light-emitting layer complementary to each other, a configuration that emits white light as a whole can be obtained. When three or more light-emitting layers are used to obtain white light emission, the emission colors of the three or more light-emitting layers may be combined to enable the light-emitting element to emit white light as a whole.

[0470] A tandem-structured element 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. To obtain white light emission, light from the light-emitting layers of the light-emitting units may be combined to obtain white light emission. The structure for obtaining white light emission is the same as that of the single-structure element. In a tandem-structured element, it is preferable to provide an intermediate layer such as a charge-generating layer between the light-emitting units.

[0471] Furthermore, when the above-described white light-emitting element (single structure or tandem structure) is compared with a light-emitting element having an SBS structure, the light-emitting element having an SBS structure can reduce power consumption compared to the white light-emitting element. When it is desired to reduce power consumption, it is preferable to use a light-emitting element having an SBS structure. On the other hand, the manufacturing process of the white light-emitting element is simpler than that of the light-emitting element having an SBS structure, and therefore the manufacturing cost can be reduced or the manufacturing yield can be increased, making it preferable.

[0472] ACTF: circuit, AFP: circuit, ALP: array section, BW: bus wiring, C1: capacitor, C1r: capacitor, C5: capacitor, C5m: capacitor, CA: cell array, F1: transistor, F1m: transistor, F2: transistor, F2m: transistor, F3: transistor, F4: transistor, HC: holding section, ILD: circuit, ITRZ: circuit, M1: transistor, M1r: transistor, M2: transistor, M3: transistor, M3r: transistor, MAC1: arithmetic circuit, MC: circuit, MCr: circuit, MP: circuit, NN: node, NNref: node , n1: node, OL: wiring, OLB: wiring, SWL1: wiring, SWL2: wiring, SWS1: circuit, SWS2: circuit, TW: circuit, VE: wiring, VER: wiring, WCL: wiring, WCS: circuit, WL: wiring, WLD: circuit, WSD: circuit, WSL: wiring, WX1L: wiring, XCL: wiring, XCS: circuit, XLD: circuit, 10: display device, 61: light-emitting element, 61B: light-emitting element, 61G: light-emitting element, 61IR: light-emitting element, 61LS: light-emitting element, 61R: light-emitting element, 62: light-receiving element, 80: pixel, 81: common electrode, 82: connection electrode, 83: substrate, 84: pixel electrode, 84B: pixel electrode, 84G: pixel electrode, 84IR: pixel electrode, 84PD: pixel electrode, 84R: pixel electrode, 85: hole injection layer, 85B: hole injection layer, 85G: hole injection layer, 85IR: hole injection layer, 85R: hole injection layer, 86: hole transport layer, 86B: hole transport layer, 86G: hole transport layer, 86IR: hole transport layer, 86PD: hole transport layer, 86R: hole transport layer, 87: light-emitting layer, 87B: light-emitting layer, 87G: light-emitting layer, 87IR: light-emitting layer, 87R: light-emitting layer, 88: electron transport layer, 88B: electron transport layer, 88G: electron transport layer, 88IR: electron transport layer, 88PD: electron transport layer , 88R: electron transport layer, 89: common layer, 90: light receiving layer, 91: protective layer, 92: insulating layer, 93: connecting portion, 94: insulating layer, 95: display area, 96: insulating layer, 100: display device, 101: substrate, 102: substrate, 103: support plate, 104: sensor portion, 105: protective member, 106: layer, 108: eyeball, 109: display area, 110: light emitting element, 110B: light emitting element, 110G: light emitting element, 110IR: light emitting element, 110LS: light emitting element, 110R: light emitting element, 120: drive circuit portion, 121: image processing portion, 122: frame memory, 150: electronic device, 151: optical system,153: motion detection unit, 154: audio, 155: camera, 156: control unit, 157: communication unit, 158: battery, 240: capacitor, 241: conductive layer, 243: insulating layer, 245: conductive layer, 251: conductive layer, 252: conductive layer, 254: insulating layer, 255: insulating layer, 256: plug, 261: insulating layer, 262: insulating layer, 263: insulating layer, 264: insulating layer, 265: insulating layer, 271: plug, 274: plug, 275: insulating layer, 301: substrate, 310: transistor, 311: conductive layer, 312: low resistance region, 313: insulating layer, 314: insulating layer, 315: element isolation layer, 320: transistor, 321: semiconductor layer, 323: insulating layer, 324: conductive layer, 325: conductive layer, 326: insulating layer, 327: conductive layer, 328: insulating layer, 329: insulating layer, 332: insulating layer, 350: arithmetic circuit, 370B: light-emitting element, 370G: light-emitting element, 370IR: light-emitting element, 370PD: light-receiving element, 370R: light-emitting element, 370SR: light-receiving / light-emitting element, 371: pixel electrode, 373: active layer, 375: common electrode, 377: first electrode, 378: second electrode, 380A: display device, 380B: display device, 380C: display device, 380D: display device, 381 : hole injection layer, 382: hole transport layer, 382-1: hole transport layer, 382-2: hole transport layer, 383: light emitting layer, 383B: light emitting layer, 383G: light emitting layer, 383IR: light emitting layer, 383R: light emitting layer, 384: electron transport layer, 385: electron injection layer, 389: layer, 419: resin layer, 420: substrate, 672: electrode, 686: EL layer, 686a: EL layer, 686b: EL layer, 688: electrode, 700: electronic device, 701: display device, 702: housing, 703: optical member, 704: mounting portion, 705: camera, 706: display area, 711: lens, 712: reflector, 713: reflector Surface, 715: Light, 716: Transmitted light, 750: Electronic device, 751: Display device, 752: Housing, 754: Mounting portion, 754A: Earphone, 754B: Earphone, 755: Buffer material, 756: Lens, 757: Input terminal, 758: Output terminal, 4411: Light-emitting layer, 4412: Light-emitting layer, 4413: Light-emitting layer, 4420: Layer, 4420-1: Layer, 4420-2: Layer, 4430: Layer, 4430-1: Layer, 4430-2: Layer, 8200: Electronic device, 8201: Mounting portion, 8202: Lens, 8203: Main body, 8204: Display portion, 8205: Cable, 8206: Battery,8300: electronic device, 8301: housing, 8302: display unit, 8304: fixture, 8305: lens, 8400: electronic device, 8401: housing, 8402: mounting unit, 8403: cushioning member, 8404: display unit, 8405: lens,

Claims

1. An electronic device having an eye tracking function, A display device; an optical system; the display device includes a first light-emitting element, a second light-emitting element, a sensor unit, and a drive circuit unit; The sensor unit has a light receiving element, The first light-emitting element has a function of emitting infrared light, The second light-emitting element has a function of emitting visible light, The light receiving element has a function of detecting the infrared light emitted by the first light emitting element and reflected by an eyeball of a user, the first light-emitting element and the second light-emitting element are disposed on the same layer; the first light-emitting element and the second light-emitting element have a common electrode; When viewed from above, the common electrode and the light receiving element have an overlapping area, the layer in which the first light emitting element and the second light emitting element are located overlaps with the sensor unit; electronic equipment.

2. In claim 1, The display device further includes a first substrate and a second substrate, the first substrate is disposed between the first light emitting element, the second light emitting element, and the sensor unit; the second substrate overlaps the first substrate via the first light emitting element and the second light emitting element; the first substrate is transparent to at least infrared light; The second substrate is transparent to visible light and infrared light. electronic equipment.

3. In claim 1 or 2, The light receiving element is formed on a silicon substrate. electronic equipment.

4. An electronic device having an eye tracking function, A display device; an optical system; the display device includes a first light-emitting element, a second light-emitting element, a sensor unit, and a drive circuit unit; The sensor unit has a light receiving element, The first light-emitting element has a function of emitting infrared light, The second light-emitting element has a function of emitting visible light, The light receiving element has a function of detecting the infrared light emitted by the first light emitting element and reflected by an eyeball of a user, the first light-emitting element and the second light-emitting element have a common electrode; When viewed from above, the common electrode and the light receiving element have an overlapping area, the first light-emitting element, the second light-emitting element, and the sensor unit are arranged in parallel with upper surfaces of pixel electrodes of the first light-emitting element and the second light-emitting element; electronic equipment.

5. In claim 4, The display device further includes a first substrate and a second substrate, the first substrate overlaps with the second substrate via the first light-emitting element, the second light-emitting element, and the sensor unit; The second substrate is transparent to visible light and infrared light. electronic equipment.

6. In any one of claims 1 to 5, The first light-emitting element is disposed outside a display area when viewed from above. electronic equipment.

7. In any one of claims 1 to 5, The first light-emitting element is disposed within a display region when viewed from above. electronic equipment.

8. In any one of claims 1 to 7, The sensor unit is disposed within the display area when viewed from above. electronic equipment.

9. In any one of claims 1 to 7, The sensor unit is disposed outside the display area when viewed from above. electronic equipment.

10. In any one of claims 1 to 9, The display device further includes an image processing unit, performing gaze tracking using the first light-emitting element, the sensor unit, and the image processing unit; electronic equipment.

11. In claim 10, The image processing unit includes an arithmetic circuit having a function of performing a product-sum operation. electronic equipment.

12. In claim 11, the arithmetic circuit includes a transistor including a metal oxide in a channel formation region; electronic equipment.

13. In any one of claims 1 to 12, The second light-emitting element has a function of emitting red, green, or blue light. electronic equipment.

14. In any one of claims 1 to 13, a light-emitting layer of the first light-emitting element and a light-emitting layer of the second light-emitting element each contain a light-emitting organic compound; electronic equipment.

15. An electronic device having an eye tracking function, A display device and an optical system are included. the display device includes a first light-emitting element, a second light-emitting element, an organic photodiode, and a drive circuit unit; the first light-emitting element and the second light-emitting element have a function of emitting visible light, the organic photodiode has a function of detecting the visible light emitted by the first light emitting element and reflected by the eyeball of a user; the first light emitting element is disposed outside a display area when viewed from above, the second light emitting element is disposed inside the display area in a top view, the first light-emitting element, the second light-emitting element, and the organic photodiode are disposed in the same layer; electronic equipment.

16. In claim 15, The display device further includes a first substrate and a second substrate, the first light-emitting element, the second light-emitting element, and the organic photodiode are disposed between the first substrate and the second substrate; the first light-emitting element, the second light-emitting element, and the organic photodiode are arranged parallel to an upper surface of the first substrate; The second substrate is transparent to visible light. electronic equipment.

17. In claim 15 or 16, The organic photodiode is disposed inside the display area when viewed from above. electronic equipment.

18. In claim 15 or 16, The organic photodiode is disposed outside the display area when viewed from above. electronic equipment.

19. In any one of claims 15 to 18, The display device further includes an image processing unit, performing gaze tracking using the first light-emitting element, the organic photodiode, and the image processing unit; electronic equipment.

20. 20. In claim 19, The image processing unit includes an arithmetic circuit having a function of performing a product-sum operation. electronic equipment.

21. In claim 20, the arithmetic circuit includes a transistor including a metal oxide in a channel formation region; electronic equipment.

22. In any one of claims 15 to 21, The first light-emitting element has a function of emitting red light. electronic equipment.

23. In any one of claims 15 to 22, a light-emitting layer of the first light-emitting element and a light-emitting layer of the second light-emitting element each contain a light-emitting organic compound; electronic equipment.