Electronic device

Abstract

Provided is an electronic device capable of measuring a blood flow rate in, for example, a retinal blood vessel of an eye. This electronic device has a display unit, a transmitting unit, a receiving unit, and a control circuit. The transmitting unit has: a function of generating a first ultrasonic wave with a first frequency; and a function of transmitting, to the control circuit, a first electrical signal according to the first frequency. The receiving unit has: a function of receiving a second ultrasonic wave that is generated from the first ultrasonic wave reflected by an object and has a second frequency; a function of generating a second electrical signal according to the second frequency; and a function of transmitting the second electrical signal to the control circuit. Incidentally, the object is one or more blood vessels selected from retinal blood vessels and blood vessels included in the retina of an eye of a user. The control circuit has: a function of calculating the blood flow rate of the one or more blood vessels selected from retinal blood vessels and blood vessels included in the retina using the first electrical signal and the second electrical signal; and a function of transmitting a third electrical signal according to the blood flow rate to the display unit. The display unit has a function of receiving the third electrical signal and displaying the blood flow rate.

Description

electronic equipment

[0001] One aspect of the present invention relates to an electronic device.

[0002] Note that one embodiment of the present invention is not limited to the above technical field. The technical field of the invention disclosed in this specification and the like relates to an object, a driving method, or a manufacturing method. Alternatively, one embodiment of the present invention relates to a process, a machine, manufacture, or a composition of matter. Therefore, specific examples of the technical field of one embodiment of the present invention disclosed in this specification include a semiconductor device, a display device, a liquid crystal display device, a light-emitting device, a power storage device, an imaging device, a memory device, a signal processing device, a processor, an electronic device, a system, a driving method thereof, a manufacturing method thereof, or an inspection method thereof.

[0003] There is a demand for display devices that can be applied to XR (Cross Reality or Extended Reality) such as VR (Virtual Reality) and AR (Augmented Reality). Specifically, for example, in order to enhance the sense of realism and immersion, the display devices are desired to have high definition and excellent color reproducibility.

[0004] Examples of display devices that can be applied to the display include liquid crystal display devices. Examples of display devices that can be applied to the display include light-emitting devices that include light-emitting devices such as organic electroluminescence (EL) devices or light-emitting diodes (LEDs). Patent Document 1 discloses a high-pixel, high-resolution display device that includes a light-emitting device that includes an organic EL device.

[0005] Furthermore, because electronic devices for XR (e.g., head-mounted displays) are intended to be worn on the head, the distance between the eyes of the user wearing the electronic device and the display unit provided on the electronic device is inevitably short. Furthermore, when wearing an electronic device for XR, the user tends to spend longer periods of time looking directly at the display unit. For these reasons, wearing an electronic device for XR can easily cause eye fatigue, leading to drowsiness, decreased concentration, and other issues.

[0006] For this reason, methods for measuring eye fatigue have attracted attention. Patent Document 2 discloses a visual fatigue measurement device that determines a user's visual fatigue level by comparing eye movements over two or more time periods.

[0007] International Publication No. 2019 / 220278 International Publication No. 2012 / 160741

[0008] One example of a method for measuring the degree of eye fatigue of a user is to capture an image of the user's eyes using an imaging device. For example, by providing an imaging device for capturing an image of the user's eyes around the display unit of an XR electronic device, the user's eyes can be monitored while the user is using the XR electronic device. Furthermore, by monitoring the user's eyes, the imaging device can also measure the state of the fundus of the eye.

[0009] However, if a user suffers from a disease such as cataracts, it is difficult to capture an image of the fundus of the user's eye using an imaging device because the cataract causes the lens of the user's eye to become cloudy, and the cloudy area of ​​the lens prevents the fundus from being captured.

[0010] An object of one embodiment of the present invention is to provide an electronic device that measures a blood flow velocity in a user's eye. Another object of one embodiment of the present invention is to provide an electronic device that measures a body temperature around a user's eye. Another object of one embodiment of the present invention is to provide an electronic device that measures a user's pulse. Another object of one embodiment of the present invention is to provide an electronic device that measures a user's blood oxygen saturation. Another object of one embodiment of the present invention is to provide any of the above-described electronic devices that include a display device. Another object of one embodiment of the present invention is to provide a novel electronic device.

[0011] Note that the problems of one embodiment of the present invention are not limited to the problems listed above. The problems listed above do not preclude the existence of other problems. Note that the other problems are problems not mentioned in this section, which will be described below. Problems not mentioned in this section can be derived by a person skilled in the art from the description in the specification or drawings, and can be appropriately extracted from these descriptions. Note that one embodiment of the present invention solves at least one of the problems listed above and other problems. Note that one embodiment of the present invention does not necessarily solve all of the problems listed above and other problems.

[0012] (1) One aspect of the present invention is an electronic device having a display unit, a transmitter unit, a receiver unit, and a control circuit. The transmitter unit has a function of generating a first ultrasonic wave of a first frequency and a function of transmitting a first electrical signal corresponding to the first frequency to the control circuit. The receiver unit has a function of receiving a second ultrasonic wave of a second frequency that is the first ultrasonic wave reflected by an object, a function of generating a second electrical signal corresponding to the second frequency, and a function of transmitting the second electrical signal to the control circuit. The object is one or more selected from retinal blood vessels of a user's eye and blood vessels included in the fundus. The control circuit has a function of calculating a blood flow velocity of the retinal blood vessels and one or more selected from the blood vessels using the first electrical signal and the second electrical signal, and a function of transmitting a third electrical signal corresponding to the blood flow velocity to the display unit. The display unit has a function of receiving the third electrical signal and displaying the blood flow velocity.

[0013] (2) Alternatively, in one aspect of the present invention, in the above (1), an audio output unit may be further included. Preferably, the control circuit has a function of transmitting a fourth electrical signal corresponding to the blood flow velocity to the audio output unit, and the audio output unit has a function of receiving the fourth electrical signal and generating audio corresponding to the fourth electrical signal.

[0014] (3) Alternatively, one aspect of the present invention may have a configuration in (1) or (2) above, including a housing. Preferably, the housing includes a display unit, a transmitter, a receiver, and a control circuit. Preferably, the housing has a structure to be worn on a user's head, and when the housing is worn on the user's head, the display unit is located in a region overlapping the user's eye, and the transmitter and receiver are located so as to be aligned in one direction with the user's eye in a front view.

[0015] (4) Another aspect of the present invention is an electronic device having a display unit and a sensor unit. The display unit has a first region and a second region, and each of the first region and the second region has a light-emitting device. The second region has a light-receiving device. The sensor unit has a diamond layer having an NV center, and the sensor unit is located in a region overlapping the first region. A wall is provided between the first region and the second region, and the wall functions to prevent light from the light-emitting devices in the first region and the second region from entering each other's region. The sensor unit has a function of emitting second light to the light-receiving device in the second region when first light from the light-emitting device included in the second region is incident on the sensor unit. This allows temperature to be measured from the intensity of the second light.

[0016] In this specification and the like, a semiconductor device is a device that utilizes semiconductor characteristics, and refers to a circuit including a semiconductor element (for example, a transistor, a diode, and a photodiode), a device having such a circuit, etc. It also refers to any device that can function by utilizing semiconductor characteristics. For example, an integrated circuit, a chip including an integrated circuit, and an electronic component that houses a chip in a package are each an example of a semiconductor device. Furthermore, a memory device, a display device, a light-emitting device, a lighting device, and an electronic device may themselves be a semiconductor device or may include a semiconductor device.

[0017] Furthermore, when it is stated in this specification that X and Y are connected, it is understood that the following cases are disclosed in this specification: when X and Y are electrically connected, when X and Y are functionally connected, and when X and Y are directly connected. Therefore, it is not limited to a specific connection relationship, for example, a connection relationship shown in a figure or text, and it is understood that connections other than those shown in a figure or text are also disclosed in a figure or text. X and Y are understood to be objects (e.g., devices, elements, circuits, wiring, electrodes, terminals, conductive films, and layers).

[0018] As an example of a case where X and Y are electrically connected, one or more elements (for example, a switch, a transistor, a capacitance element, an inductor, a resistance element, a diode, a display device, a light-emitting device, and a load) that enable the electrical connection between X and Y can be connected between X and Y. The switch has a function of controlling on / off. In other words, the switch has a function of being in a conductive state (on state) or a non-conductive state (off state) and controlling whether or not a current flows.

[0019] As an example of a case where X and Y are functionally connected, one or more circuits that enable the functional connection between X and Y (for example, logic circuits (for example, inverters, NAND circuits, and NOR circuits), signal conversion circuits (for example, digital-analog conversion circuits, analog-digital conversion circuits, and gamma correction circuits), potential level conversion circuits (for example, power supply circuits such as step-up circuits or step-down circuits, and level shifter circuits that change the potential level of a signal), voltage sources, current sources, switching circuits, amplifier circuits (for example, circuits that can increase the signal amplitude or current amount, operational amplifiers, differential amplifier circuits, source follower circuits, and buffer circuits), signal generation circuits, memory circuits, and control circuits) can be connected between X and Y. As an example, even if another circuit is sandwiched between X and Y, X and Y are considered to be functionally connected if a signal output from X is transmitted to Y.

[0020] It should be noted that when it is explicitly stated that X and Y are electrically connected, this includes the case where X and Y are electrically connected (i.e., the case where X and Y are connected with another element or another circuit sandwiched between them) and the case where X and Y are directly connected (i.e., the case where X and Y are connected without another element or another circuit sandwiched between them).

[0021] Furthermore, this specification deals with a circuit configuration in which multiple elements are electrically connected to wiring (a wiring that supplies a constant potential or a wiring that transmits a signal). For example, if X and the wiring are directly and electrically connected, and Y and the wiring are also directly and electrically connected, this specification may state that X and Y are directly and electrically connected.

[0022] Furthermore, for example, it can be expressed as follows: "X, Y, the source (sometimes referred to as either the first terminal or the second terminal) and the drain (sometimes referred to as the other of the first terminal or the second terminal) of the transistor are electrically connected to each other, and are electrically connected in the order of X, the source of the transistor, the drain of the transistor, and Y." Or, it can be expressed as follows: "The source of the transistor is electrically connected to X, the drain of the transistor is electrically connected to Y, and X, the source of the transistor, the drain of the transistor, and Y are electrically connected in this order." Or, it can be expressed as follows: "X is electrically connected to Y through the source and drain of the transistor, and X, the source of the transistor, the drain of the transistor, and Y are provided in this connection order." By using expressions similar to these examples to specify the order of connections in the circuit configuration, it is possible to distinguish between the source and drain of the transistor and determine the technical scope. Note that these expressions are merely examples and are not limiting. Here, X and Y are assumed to be objects (for example, a device, an element, a circuit, a wiring, an electrode, a terminal, a conductive film, or a layer).

[0023] Note that even when independent components are shown electrically connected to each other in a circuit diagram, one component may have the functions of multiple components. For example, if part of a wiring also functions as an electrode, one conductive film has the functions of both a wiring and an electrode. Therefore, the term "electrically connected" in this specification also includes such cases where one conductive film has the functions of multiple components.

[0024] Furthermore, in this specification, a "resistance element" can be, for example, a circuit element having a resistance value higher than 0Ω, or a wiring having a resistance value higher than 0Ω. Therefore, in this specification, a "resistance element" includes a wiring having a resistance value, a transistor in which a current flows between a source and a drain, a diode, a coil, etc. Therefore, the term "resistance element" can sometimes be replaced with the terms "resistance," "load," or "region having a resistance value." Conversely, the terms "resistance," "load," or "region having a resistance value" can sometimes be replaced with the term "resistance element." The resistance value can be, for example, preferably 1 mΩ or more and 10 Ω or less, more preferably 5 mΩ or more and 5 Ω or less, and even more preferably 10 mΩ or more and 1 Ω or less. Furthermore, for example, a resistance value can be replaced with a resistance value of 1 Ω or more and 1×10 ９ It may be set to Ω or less.

[0025] Furthermore, in this specification and the like, a "capacitive element" can refer to, for example, a circuit element having a capacitance value higher than 0 F, a region of a wiring having a capacitance value higher than 0 F, a parasitic capacitance, or a gate capacitance of a transistor. The terms "capacitive element," "parasitic capacitance," or "gate capacitance" can sometimes be replaced with the term "capacitance." Conversely, the term "capacitance" can sometimes be replaced with the terms "capacitive element," "parasitic capacitance," or "gate capacitance." The term "pair of electrodes" in "capacitance" can also be replaced with "pair of conductors," "pair of conductive regions," or "pair of regions." The capacitance value can be, for example, 0.05 fF or more and 10 pF or less. It may also be, for example, 1 pF or more and 10 μF or less.

[0026] Furthermore, in this specification, a transistor has three terminals called a gate, a source, and a drain. The gate is a control terminal that controls the conduction state of the transistor. The two terminals that function as a source or a drain are input / output terminals of the transistor. One of the two input / output terminals serves as a source and the other as a drain depending on the conductivity type (n-channel or p-channel) of the transistor and the level of the potential applied to the three terminals of the transistor. Therefore, in this specification, the terms "source" and "drain" may be interchangeable. Furthermore, in this specification, 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. Note that, depending on the structure of a transistor, a backgate may be included in addition to the three terminals described above. In this case, in this specification, one of the gate or backgate of the transistor may be referred to as a first gate, and the other of the gate or backgate of the transistor may be referred to as a second gate. Furthermore, for the same transistor, the terms "gate" and "backgate" may be interchangeable. Furthermore, when a transistor has three or more gates, the gates may be referred to as a first gate, a second gate, a third gate, and so on in this specification.

[0027] For example, in this specification, a transistor having a multi-gate structure with two or more gate electrodes can be used as an example of a transistor. In a multi-gate structure, the channel formation regions are connected in series, resulting in a structure in which multiple transistors are connected in series. Therefore, the multi-gate structure can reduce the off-state current and improve the breakdown voltage (reliability) of the transistor. Alternatively, when operating in the saturation region, the multi-gate structure can provide voltage-current characteristics with a flat slope, such that the current between the drain and source does not change significantly even when the voltage between the drain and source changes. By utilizing voltage-current characteristics with a flat slope, an ideal current source circuit or an active load with a very high resistance value can be realized. As a result, a differential circuit or a current mirror circuit with excellent characteristics can be realized.

[0028] Furthermore, even when a single circuit element is shown on a circuit diagram, the circuit element may include multiple circuit elements. For example, when a single resistor is shown on a circuit diagram, this includes two or more resistors electrically connected in series. For example, when a single capacitor is shown on a circuit diagram, this includes two or more capacitors electrically connected in parallel. For example, when a single transistor is shown on a circuit diagram, this includes two or more transistors electrically connected in series, with the gates of the respective transistors electrically connected to each other. Similarly, when a single switch is shown on a circuit diagram, this includes two or more transistors, with the switch including two or more transistors electrically connected in series or parallel, and the gates of the respective transistors electrically connected to each other.

[0029] Furthermore, in this specification and the like, a node can be referred to as a terminal, a wiring, an electrode, a conductive layer, a conductor, an impurity region, etc. depending on the circuit configuration and device structure. Furthermore, a terminal, a wiring, etc. can be referred to as a node.

[0030] 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 the ground potential (earth potential), then "voltage" can be interchanged with "potential." Note that ground potential does not necessarily mean 0 V. Furthermore, potential is relative, and as the reference potential changes, the potential applied to wiring, the potential applied to a circuit, etc., the potential output from a circuit, etc. also changes.

[0031] Furthermore, in this specification and the like, the terms "high-level potential" and "low-level potential" do not mean specific potentials. For example, when two wirings are both described as "functioning as wirings that supply a high-level potential," the high-level potentials provided by both wirings do not have to be equal to each other. Similarly, when two wirings are both described as "functioning as wirings that supply a low-level potential," the low-level potentials provided by both wirings do not have to be equal to each other.

[0032] "Current" refers to the phenomenon of charge transfer (electrical conduction). For example, the statement "electrical conduction of a positively charged body is occurring" can be rephrased as "electrical conduction of a negatively charged body is occurring in the opposite direction." Therefore, in this specification, unless otherwise specified, "current" refers to the phenomenon of charge transfer (electrical conduction) associated with the movement of carriers. Examples of carriers here include electrons, holes, anions, cations, and complex ions, and the carriers differ depending on the system through which the current flows (e.g., semiconductor, metal, electrolyte, and vacuum). Furthermore, the "direction of current" in wiring refers to the direction in which positively charged carriers move and is expressed as a positive current amount. In other words, the direction in which negatively charged carriers move is opposite to the direction of current and is expressed as a negative current amount. Therefore, in this specification, unless otherwise specified regarding the positive / negative sign of the current (or the direction of current), the statement "current flows from element A to element B" can be rephrased as "current flows from element B to element A." Furthermore, the statement "current is input to element A" can be rephrased as "current is output from element A."

[0033] Furthermore, in this specification, the ordinal numbers "first," "second," and "third" are used to avoid confusion between components. Therefore, they do not limit the number of components. Furthermore, they do not limit the order of the components. For example, a component referred to as "first" in one embodiment of this specification may be a component referred to as "second" in another embodiment or in the claims. Furthermore, for example, a component referred to as "first" in one embodiment of this specification may be omitted in another embodiment or in the claims.

[0034] Furthermore, in this specification, terms indicating arrangement such as "above" and "below" may be used for convenience in describing the positional relationship between components with reference to the drawings. Furthermore, the positional relationship between components changes as appropriate depending on the direction in which each component is depicted. Therefore, the terms are not limited to those described in the specification, and can be rephrased appropriately depending on the situation. For example, the expression "insulator located on the upper surface of a conductor" can be rephrased as "insulator located on the lower surface of a conductor" by rotating the orientation of the drawing 180 degrees.

[0035] Furthermore, the terms "above" and "below" do not limit the positional relationship of components to being directly above or below and in direct contact with each other. For example, the expression "electrode B on insulating layer A" does not require that electrode B be formed on insulating layer A in direct contact with it, and does not exclude the inclusion of other components between insulating layer A and electrode B.

[0036] Furthermore, in this specification, terms such as "row" and "column" may be used to describe components arranged in a matrix and their positional relationships. Furthermore, the positional relationships between components change as appropriate depending on the direction in which each component is depicted. Therefore, the terms are not limited to those used in the specification, and may be rephrased appropriately depending on the situation. For example, the expression "row direction" may be rephrased as "column direction" by rotating the orientation of the drawing by 90 degrees.

[0037] Furthermore, in this specification and the like, the terms "film" and "layer" can be interchanged depending on the situation. For example, the term "conductive layer" may be changed to the term "conductive film". Or, for example, the term "insulating film" may be changed to the term "insulating layer". Or, in some cases or depending on the situation, the terms "film" and "layer" may not be used and may be replaced with other terms. For example, the terms "conductive layer" or "conductive film" may be changed to the term "conductor". Or, for example, the terms "insulating layer" or "insulating film" may be changed to the term "insulator".

[0038] Furthermore, the terms "electrode," "wiring," and "terminal" 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" or "wiring" include cases where multiple "electrodes" or "wirings" are integrally formed. Furthermore, for example, a "terminal" may be used as part of a "wiring" or "electrode," and vice versa. Furthermore, the term "terminal" includes cases where one or more selected from "electrode," "wiring," and "terminal" are integrally formed. Therefore, for example, an "electrode" can be part of a "wiring" or "terminal," and a "terminal" can be part of a "wiring" or "electrode." Furthermore, terms such as "electrode," "wiring," and "terminal" may be replaced with terms such as "region" in some cases.

[0039] Furthermore, in this specification and the like, terms such as "wiring," "signal line," or "power line" may be interchangeable depending on the circumstances. For example, the term "wiring" may be changed to the term "signal line." For example, the term "wiring" may be changed to the term "power line." Vice versa, terms such as "signal line" or "power line" may be changed to the term "wiring." The term "power line" may be changed to the term "signal line." Vice versa, terms such as "signal line" may be changed to the term "power line." Furthermore, the term "potential" applied to a wiring may be changed to the term "signal" depending on the circumstances. Vice versa, the term "signal" may be changed to the term "potential."

[0040] In this specification and the like, the term "impurities" in a semiconductor refers to, for example, elements other than the main component constituting the semiconductor layer. For example, an element with a concentration of less than 0.1 atomic % is an impurity. The presence of impurities may cause, for example, an increase in the defect level density of the semiconductor, a decrease in carrier mobility, a decrease in crystallinity, and the like. When the semiconductor is an oxide semiconductor, examples of impurities that change the semiconductor characteristics include, for example, Group 1 elements, Group 2 elements, Group 13 elements, Group 14 elements, Group 15 elements, and transition metals other than the main component, particularly, for example, hydrogen (also contained in water), lithium, sodium, silicon, boron, phosphorus, carbon, and nitrogen. Specifically, when the semiconductor is a silicon layer, examples of impurities that change the semiconductor characteristics include, for example, Group 1 elements, Group 2 elements, Group 13 elements, and Group 15 elements (excluding oxygen and hydrogen).

[0041] In this specification, a switch refers to a device that can be in a conductive state (on state) or a non-conductive state (off state) and has the function of controlling whether or not a current flows. Alternatively, a switch refers to a device that has the function of selecting and switching a path through which a current flows. Therefore, a switch may have two or more terminals through which a current flows, in addition to a control terminal. As an example, an electrical switch, a mechanical switch, or the like can be used. In other words, the switch is not limited to a specific type as long as it can control a current.

[0042] Examples of electrical switches include transistors (e.g., bipolar transistors, MOS transistors, etc.), diodes (e.g., PN diodes, PIN diodes, Schottky diodes, MIM (Metal Insulator Metal) diodes, MIS (Metal Insulator Semiconductor) diodes, diode-connected transistors, etc.), and logic circuits combining these. When a transistor is used as a switch, the "conductive state" of the transistor refers to, for example, a state in which the source electrode and drain electrode of the transistor can be considered to be electrically short-circuited, or a state in which current can flow between the source electrode and drain electrode. The "non-conductive state" of the transistor refers to a state in which the source electrode and drain electrode of the transistor can be considered to be electrically disconnected. When a transistor is operated simply as a switch, the polarity (conductivity type) of the transistor is not particularly limited.

[0043] An example of a mechanical switch is a switch that uses MEMS (microelectromechanical systems) technology. This switch has a mechanically movable electrode, and the movement of the electrode controls whether the switch is conductive or non-conductive.

[0044] In this specification, etc., a device fabricated using a metal mask or an FMM (fine metal mask, high-resolution metal mask) may be referred to as a device with an MM (metal mask) structure. In this specification, etc., a device fabricated without using a metal mask or an FMM may be referred to as a device with an MML (metal maskless) structure.

[0045] In this specification and the like, a structure in which different light-emitting layers are formed or different light-emitting layers are painted for each color light-emitting device (here, blue (B), green (G), and red (R)) may be referred to as an SBS (Side By Side) structure. In this specification and the like, a light-emitting device that can emit white light may be referred to as a white light-emitting device. In addition, a white light-emitting device can be combined with a colored layer (e.g., a color filter) to form a full-color display device.

[0046] Furthermore, light-emitting devices can be broadly divided into single structures and tandem structures. A single-structure device has one light-emitting unit between a pair of electrodes, and the light-emitting unit preferably includes one or more light-emitting layers. To obtain white light emission, two or more light-emitting layers may be selected so that the light emitted from each of the two or more light-emitting layers has a complementary color relationship. For example, by making the emission color of the first light-emitting layer and the emission color of the second light-emitting layer complementary, a configuration in which the entire light-emitting device emits white light can be obtained. The same applies to light-emitting devices having three or more light-emitting layers.

[0047] A tandem-structure device preferably has two or more light-emitting units between a pair of electrodes, and each light-emitting unit preferably includes one or more light-emitting layers. 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 configuration for obtaining white light emission is the same as that of the single-structure device. In a tandem-structure device, it is preferable to provide an intermediate layer such as a charge-generating layer between the light-emitting units.

[0048] Furthermore, when comparing the above-described white light-emitting device (single structure or tandem structure) with a light-emitting device having an SBS structure, the light-emitting device having an SBS structure can reduce power consumption compared to the white light-emitting device. If it is desired to reduce power consumption, it is preferable to use a light-emitting device having an SBS structure. On the other hand, the manufacturing process of a white light-emitting device is simpler than that of a light-emitting device having an SBS structure, and therefore the manufacturing cost can be reduced or the manufacturing yield can be increased, making it preferable.

[0049] In this specification, "parallel" refers to a state in which two straight lines are arranged at an angle of -10° or more and 10° or less. Therefore, it also includes cases where the angle is -5° or more and 5° or less. Furthermore, "substantially parallel" or "roughly parallel" refers to a state in which two straight lines are arranged at an angle of -30° or more and 30° or less. Furthermore, "perpendicular" refers to a state in which two straight lines are arranged at an angle of 80° or more and 100° or less. Therefore, it also includes cases where the angle is 85° or more and 95° or less. Furthermore, "substantially perpendicular" or "approximately perpendicular" refers to a state in which two straight lines are arranged at an angle of 60° or more and 120° or less.

[0050] According to one aspect of the present invention, an electronic device that measures the blood flow velocity of a user's eye can be provided. Alternatively, according to one aspect of the present invention, an electronic device that measures the body temperature around a user's eye can be provided. Alternatively, according to one aspect of the present invention, an electronic device that measures the pulse rate of a user can be provided. Alternatively, according to one aspect of the present invention, an electronic device that measures the blood oxygen saturation level of a user can be provided. Alternatively, according to one aspect of the present invention, any of the above-described electronic devices including a display device can be provided. Alternatively, according to one aspect of the present invention, a novel electronic device can be provided.

[0051] The effects of one embodiment of the present invention are not limited to the effects listed above. The effects listed above do not preclude the existence of other effects. The other effects are described below and are not mentioned in this section. Effects not mentioned in this section can be derived by a person skilled in the art from the description in the specification or drawings, and can be extracted as appropriate from these descriptions. One embodiment of the present invention has at least one of the effects listed above and other effects. Therefore, one embodiment of the present invention may not have the effects listed above in some cases.

[0052] FIG. 1A is a perspective view showing an example of the configuration of an electronic device, and FIGS. 1B and 1C are schematic diagrams showing examples of a circuit included in the electronic device and an eye. FIG. 2 is a schematic diagram showing examples of a circuit included in the electronic device and a blood vessel. FIGS. 3A, 3C, and 3E are top views showing an example of the configuration of an electronic device, and FIGS. 3B, 3D, and 3F are front views showing an example of the configuration of an electronic device. FIGS. 4A and 4C are top views showing an example of the configuration of an electronic device, and FIG. 4B is a front view showing an example of the configuration of an electronic device. FIG. 5 is a perspective view showing an example of the configuration of an electronic device. FIG. 6 is a block diagram showing an example of the configuration of an electronic device. FIG. 7 is a block diagram showing an example of the configuration of an electronic device. FIG. 8 is a block diagram showing an example of the configuration of an electronic device. FIG. 9A is a cross-sectional view showing an example of the configuration of a sensor, and FIG. 9B is a block diagram showing an example of the configuration of a measurement device having the sensor. FIG. 10 is a block diagram showing an example of the configuration of an electronic device. FIG. 11 is a schematic perspective view showing an example of the configuration of a display device. FIG. 12A is a schematic perspective view showing an example of the configuration of a display device, and FIGS. 12B and 12C are front views showing an example of the configuration of an electronic device. FIG. 13 is a diagram illustrating an example of how the electronic device is used. FIGS. 14A to 14C are diagrams illustrating an example of a display on a display unit of the electronic device. FIG. 15 is a diagram illustrating an example of a display on a display unit of the electronic device. FIGS. 16A and 16B are diagrams illustrating an example of a display on a display unit of the electronic device. FIGS. 17A to 17C are diagrams illustrating an example of a display on a display unit of the electronic device. FIG. 18 is a schematic diagram illustrating a user's eye and the area around the user's eye. FIG. 19 is a diagram illustrating an example of how the electronic device is used. FIGS. 20A and 20B are diagrams illustrating an example of a configuration of a neural network. FIG. 21 is a diagram illustrating an example of a configuration of an arithmetic circuit of a neural network. FIG. 22 is a diagram illustrating an example of a configuration of an arithmetic circuit of a neural network. FIG. 23 is a diagram illustrating an example of a configuration of an arithmetic circuit of a neural network. FIG. 24 is a schematic cross-sectional view showing an example of a configuration of a display device. 25A to 25D are schematic diagrams showing configuration examples of a light-emitting device, Fig. 26 is a cross-sectional view showing a configuration example of a display device, and Figs. 27A and 27B are cross-sectional views showing configuration examples of a display device.28A and 28B are cross-sectional schematic diagrams showing a configuration example of a display device. FIGS. 29A and 29B are cross-sectional schematic diagrams showing a configuration example of a display device. FIGS. 30A and 30B are cross-sectional schematic diagrams showing a configuration example of a display device. FIGS. 31A to 31D are cross-sectional diagrams showing an example of a display device. FIGS. 32A to 32F are cross-sectional diagrams showing an example of a manufacturing method of a display device. FIG. 33A is a circuit diagram showing a configuration example of a pixel circuit included in a display device, and FIG. 33B is a perspective schematic diagram showing a configuration example of a pixel circuit included in a display device. FIGS. 34A to 34D are circuit diagrams showing a configuration example of a pixel circuit included in a display device. FIGS. 35A to 35D are circuit diagrams showing a configuration example of a pixel circuit included in a display device. FIGS. 36A and 36B are top views showing configuration examples of a light-emitting device and a light-receiving device included in a display device. FIGS. 37A to 37D are cross-sectional schematic diagrams showing configuration examples of a light-emitting device, a light-receiving device, and a connecting electrode included in a display device. Figs. 38A to 38G are plan views showing an example of a pixel. Figs. 39A to 39F are plan views showing an example of a pixel. Figs. 40A to 40H are plan views showing an example of a pixel. Figs. 41A to 41D are plan views showing an example of a pixel. Figs. 42A to 42D are plan views showing an example of a pixel. Fig. 42E is a cross-sectional view showing an example of a display device. Figs. 43A and 43B are diagrams showing an example of the configuration of a display module. Figs. 44A to 44F are diagrams showing an example of the configuration of an electronic device. Figs. 45A to 45D are diagrams showing an example of the configuration of an electronic device. Figs. 46A to 46C are diagrams showing an example of the configuration of an electronic device.

[0053] In this specification and the like, a metal oxide refers to an oxide of a metal in a broad sense. Metal oxides are classified into oxide insulators, oxide conductors (including transparent oxide conductors), oxide semiconductors (also referred to as oxide semiconductors or simply as OSs), and the like. For example, when a metal oxide is contained in a channel formation region of a transistor, the metal oxide may be referred to as an oxide semiconductor. In other words, when a metal oxide can form a channel formation region of a transistor having at least one of an amplifying function, a rectifying function, and a switching function, the metal oxide can be referred to as a metal oxide semiconductor. Furthermore, an OS transistor can be referred to as a transistor including a metal oxide or an oxide semiconductor.

[0054] In this specification and the like, nitrogen-containing metal oxides may also be collectively referred to as metal oxides. Nitrogen-containing metal oxides may also be referred to as metal oxynitrides.

[0055] In this specification and the like, the configurations shown in each embodiment can be appropriately combined with the configurations shown in other embodiments to form one aspect of the present invention. In addition, when multiple configuration examples are shown in one embodiment, the configuration examples can be appropriately combined with each other.

[0056] In addition, the content (or even a part of the content) described in one embodiment can be applied, combined, or replaced with at least one of another content (or even a part of the content) described in that embodiment and one or more other content (or even a part of the content) described in another embodiment.

[0057] 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.

[0058] Furthermore, a figure (or even a part thereof) described in one embodiment can be combined with another part of that figure, another figure (or even a part thereof) described in that embodiment, and at least one figure (or even a part thereof) described in one or more other embodiments to form even more figures.

[0059] The embodiments described in this specification are 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 invention. Therefore, the present invention should not be interpreted as being limited to the description of the embodiments. Note that in the configuration of the invention of the embodiments, the same reference numerals are used in different drawings for the same parts or parts having similar functions, and repeated description thereof may be omitted. Also, in perspective views and the like, the description of some components may be omitted to ensure clarity of the drawings.

[0060] In this specification, when the same reference numeral is used for multiple elements, and particularly when it is necessary to distinguish between them, an identification symbol such as "_1", "[n]", "[m, n]" may be added to the reference numeral. Also, when an identification symbol such as "_1", "[n]", "[m, n]" is added to the reference numeral in the drawings, etc., the identification symbol may not be added if it is not necessary to distinguish between them in this specification.

[0061] In addition, in the drawings of this specification, the size, layer thickness, or region may be exaggerated for clarity. Therefore, the drawings are not necessarily limited to the scale. Note that the drawings are schematic illustrations of ideal examples, and are not limited to the shapes or values ​​shown in the drawings. For example, variations in signals, voltages, or currents due to noise, or variations in signals, voltages, or currents due to timing differences may be included.

[0062] Embodiment 1 In this embodiment, an electronic device according to one embodiment of the present invention will be described.

[0063] 1A shows a state in which a user USR wears an electronic device HMD, which is one form of a head-mounted display. The electronic device HMD has a function of transmitting ultrasonic waves to the user USR and a function of receiving the ultrasonic waves reflected from the user USR.

[0064] 1A, the electronic device HMD includes, for example, a housing KYT, a display unit DSP, a transmitter TRM, and a receiver RCV. The electronic device HMD also includes temples TM that are part of the housing.

[0065] 1A also includes, as an example, an audio output unit SNO that functions as an earphone. The audio output unit SNO is electrically connected to a circuit within the housing KYT by a wire.

[0066] The housing KYT has, as an example, a structure that can be worn on the head of a user USR.

[0067] The housing KYT is provided with, for example, two display units DSP, one for the right eye and one for the left eye. One of the display units DSP is provided so as to be positioned in an area superimposed on one eye when the housing KYT is worn on the head of the user USR. Similarly, the other display unit DSP is provided so as to be positioned in an area superimposed on the other eye when the housing KYT is worn on the head of the user USR.

[0068] The transmitter TRM has, for example, a function of generating ultrasonic waves and propagating them to the user USR.

[0069] The receiving unit RCV has, for example, a function of receiving ultrasonic waves reflected from the user USR.

[0070] Figure 1B shows, for example, how ultrasound USW is propagated from a transmitter TRM to the eye ME of a user USR, and Figure 1C shows, for example, how ultrasound USWr reflected from the eye ME of a user USR is acquired.

[0071] In Figures 1B and 1C, the eye ME of the user USR has a cornea KM, a lens SST, a retina MM, an optic nerve SSK, a vitreous body GT, and retinal blood vessels MKN.

[0072] 1B, the ultrasonic waves USW propagating from the transmitter TRM reach the retinal blood vessels MKN and the retina MM via the cornea KM, the crystalline lens SST, and the vitreous body GT of the eye ME. Note that the ultrasonic waves USW propagating from the transmitter TRM may reach the retinal blood vessels MKN and the retina MM via a route that does not pass through the crystalline lens SST.

[0073] Also, as shown in Figure 1C, the ultrasound USWr acquired by the receiving unit RCV is the ultrasound USW propagated from the transmitting unit TRM and reflected by one or both of the retinal blood vessels MKN of the eye ME and the blood vessels contained in the fundus.

[0074] As shown in Figures 1B and 1C, ultrasound USW is propagated from the transmitter TRM, and the ultrasound USWr reflected by one or both of the retinal blood vessels MKN and the blood vessels contained in the fundus is acquired by the receiver RCV.

[0075] The difference in frequency between the ultrasonic waves USW and USWr is determined according to the velocity of blood cells flowing in the blood vessels. In other words, by acquiring the frequency of the ultrasonic waves USWr using the receiving unit RCV, it is possible to determine the blood flow velocity of at least one of the retinal blood vessels MKN of the user USR and the blood vessels included in the fundus.

[0076] As a specific example, consider a blood vessel KN and blood cells BC flowing in the blood vessel KN shown in FIG. ０ When an ultrasonic wave USW of frequency f is propagated and reflected by a blood cell BC in a blood vessel KN, and an ultrasonic wave USWr of frequency f is input to a receiving unit RCV, the blood flow velocity V is expressed as follows: V = {V Ｂ ×(f−f ０ )} / {(2cosφ)×f ０} where V Ｂ is the speed of sound in blood, and φ is the angle between the traveling direction of the blood cell and the traveling direction of the ultrasonic wave USW (ultrasonic wave USWr).

[0077] When the user USR is experiencing eye strain, the blood flow velocity of the user USR decreases compared to normal. In other words, by measuring the blood flow velocity of the user USR using the transmitter TRM, receiver RCV, etc. of the electronic device HMD, the degree of eye strain of the user USR can be checked sequentially.

[0078] In addition, blood pressure may be measured by measuring the pulse wave (the change in blood vessel volume caused by heartbeat) from the ultrasound USW and the ultrasound USWr reflected by at least one of the retinal blood vessels MKN and the blood vessels included in the fundus. Similarly, heart rate, blood oxygen saturation, etc. may also be measured.

[0079] Note that although the electronic device HMD illustrated in FIG. 1A is a goggle-type head-mounted display, the electronic device of one embodiment of the present invention may be a glasses-type head-mounted display.

[0080] Next, a configuration example of the display unit DSP, the transmission unit TRM, and the reception unit RCV included in the electronic device HMD shown in FIG. 1A will be described.

[0081] Fig. 3A is a top view of an example configuration of an HMD electronic device applicable to Fig. 1A. Note that Fig. 3A has arrows indicating the x and y directions, and in this specification, the top view shown in Fig. 3A and the like may be referred to as an xy plan view viewed from the z direction. The line of sight toward the z direction may also be referred to as a top view. Note that Fig. 3A uses right-handed coordinates, so the z direction in Fig. 3A points toward the viewer.

[0082] In this specification, one of the x direction, y direction, and z direction may be referred to as the "first direction" or "first direction." The other may be referred to as the "second direction" or "second direction." The remaining may be referred to as the "third direction" or "third direction."

[0083] Fig. 3B is a front view showing an example of the configuration of the electronic device HMD shown in Fig. 3A. In this specification, the front view shown in Fig. 3B is a zx plan view viewed from the y direction. The line of sight in the y direction may also be referred to as a front view.

[0084] The electronic device HMD shown in Figures 3A and 3B has a configuration in which the receiver RCV is provided between the display unit DSP for the right eye and the display unit DSP for the left eye. Furthermore, the transmitter TRM is provided so that the receiver RCV, the eye ME of the user USR, and the transmitter TRM are aligned in the x direction in Figure 3B (in the zx plan view viewed from the y direction). In particular, the transmitter TRM is aligned with the receiver RCV via the display unit DSP. Therefore, in Figures 3A and 3B, the transmitter TRM is provided in two locations: next to the display unit DSP for the right eye and next to the display unit DSP for the left eye.

[0085] As shown in Figures 3A and 3B, in order to propagate ultrasound USW from the transmitter TRM and efficiently acquire ultrasound USWr reflected from the retinal blood vessels MKN of the eye ME and at least one of the blood vessels contained in the fundus by the receiver RCV, it is preferable that the transmitter TRM and the receiver RCV are arranged in the electronic device HMD so that the transmitter TRM, the eye ME, and the receiver RCV are aligned in one direction in the zx plane viewed from the y direction, i.e., in front view.

[0086] The electronic device of one embodiment of the present invention is not limited to the configurations shown in Figures 3A and 3B. The configuration of the electronic device of one embodiment of the present invention may be changed as appropriate within the scope of solving the problems.

[0087] For example, an electronic device according to one aspect of the present invention may have a configuration in which the positions of the transmitter TRM and the receiver RCV are interchanged in the electronic device HMD of Fig. 3A and Fig. 3B Fig. 3C and Fig. 3D each show, as an example, the configuration of an electronic device HMD in which the positions of the transmitter TRM and the receiver RCV are interchanged in Fig. 3A and Fig. 3B .

[0088] Furthermore, for example, an electronic device according to one embodiment of the present invention may be configured such that the receiving unit RCV, the eye ME of the user USR, and the transmitting unit TRM are aligned in the z direction. Specifically, for example, the electronic device HMD shown in FIGS. 3E and 3F shows a configuration in which, in the zx plane viewed from the y direction, the transmitting unit TRM is provided above the display unit DSP, and the receiving unit RCV is provided above the display unit DSP. Therefore, the electronic device HMD shown in FIGS. 3E and 3F differs from the electronic device HMD shown in FIGS. 3A to 3D in that two transmitting units TRM and two receiving units RCV are provided.

[0089] 3A to 3F, the transmitter TRM, the display unit DSP, and the receiver RCV are configured to be arranged along the y direction or the z direction in the zx plane viewed from the y direction. However, if the ultrasound USW propagated from the transmitter TRM is reflected by at least one of the retinal blood vessels MKN of the eye ME and the blood vessels included in the fundus, and the reflected ultrasound USWr can be acquired by the receiver RCV, the positional relationship between the transmitter TRM and the receiver RCV does not have to be limited to any of the configuration examples of the electronic device HMD shown in FIGS. 3A to 3F. For example, as shown in FIG. 4A, the electronic device HMD may be configured such that the position of the transmitter TRM in the y direction is higher than the position of the receiver RCV in the y direction in the xy plane viewed from the z direction. Furthermore, although not shown, the electronic device HMD may be configured such that the position of the transmitter TRM in the y direction is lower than the position of the receiver RCV in the y direction. 4B, the electronic device HMD may be configured so that the position of the transmitter TRM in the z direction is higher than the position of the receiver RCV in the z direction in the zx plane viewed from the y direction. Also, although not shown, the electronic device HMD may be configured so that the position of the transmitter TRM in the z direction is lower than the position of the receiver RCV in the z direction.

[0090] The transmitter TRM and the receiver RCV may be provided in the temple TM, rather than inside the housing KYT that includes the display unit DSP. Specifically, as shown in Fig. 4C, the transmitter TRM and the receiver RCV may be provided inside the temple TM that is part of the housing KYT. In this case, the electronic device HMD may be configured to measure the blood flow velocity of blood vessels around the eye ME.

[0091] In Figures 3A to 4C, each electronic device HMD acquires information on one or both of blood flow velocity and pulse wave (blood pressure) from the retinal blood vessels MKN of the user USR's eye ME and the blood vessels contained in the fundus, but one aspect of the present invention may be configured to apply ultrasound to blood vessels around the user USR's eye ME rather than inside the eye ME, and acquire information on one or both of the blood flow velocity and pulse wave (blood pressure) of the blood vessels.

[0092] Note that although the display unit DSP in Figures 3A to 4C and the like has a rectangular shape, the shape of the display unit DSP included in the electronic device of one embodiment of the present invention may be, for example, a triangle, a figure with five or more vertices, a circle, an ellipse, or a curved shape.

[0093] In addition, in Figures 3A to 4C, the transmitter TRM and receiver RCV acquire information on one or both of blood flow velocity and pulse wave (blood pressure) from blood vessels around the user USR's eye ME, retinal blood vessels MKN, and blood vessels contained in the fundus, but an electronic device of one aspect of the present invention may be able to acquire information on one or both of blood flow velocity and pulse wave (blood pressure) from blood vessels in locations other than the eye ME.

[0094] Consider, for example, the electronic device HMD shown in Fig. 5. The electronic device HMD of Fig. 5 has a configuration in which the earphones of the electronic device HMD of Fig. 1A are replaced with headphones, and includes a mounting unit HP and a mounting unit HE. The mounting unit HP is, for example, a part that is mounted on the ear of the user USR, and is provided with an audio output unit and ear pads. The mounting unit HE is, for example, a part that is mounted on the head of the user USR. The mounting unit HE may also be provided with wiring. The mounting unit HE may also be provided with a circuit in addition to wiring.

[0095] Here, in the electronic device HMD of Figure 5, by providing a transmitting unit TRM and a receiving unit RCV in at least one of the temple TM, the attachment part HP, and the attachment part HE, it may be possible to obtain information on one or both of the blood flow velocity and pulse wave (blood pressure) from blood vessels in locations other than the eye ME of the user USR.

[0096] For example, in the electronic device HMD of Fig. 5, a transmitter TRM and a receiver RCV can be provided in the temple TM. Fig. 4C shows the configuration of the electronic device HMD in which the transmitter TRM and the receiver RCV are provided in the temple TM to acquire information on one or both of the blood flow velocity and the pulse wave (blood pressure) from the blood vessels at the location of the eye ME of the user USR, but it is also possible to acquire information on one or both of the blood flow velocity and the pulse wave (blood pressure) of the user USR from blood vessels other than the eye ME, for example, blood vessels included in an area of ​​the user USR that is in contact with or in close contact with the temple TM.

[0097] Also, for example, in the electronic device HMD of Fig. 5, a transmitter TRM and a receiver RCV can be provided in the wearing unit HP. As described above, the wearing unit HP is a part that is worn on the ear of the user USR, and therefore, by providing the transmitter TRM and the receiver RCV in the wearing unit HP, it is possible to acquire information on one or both of the blood flow velocity of the blood vessels and the pulse wave (blood pressure) from the blood vessels in the ear or the surrounding area.

[0098] 5, for example, a transmitter TRM and a receiver RCV can be provided in the attachment unit HE. As described above, the attachment unit HE is a part that is attached to the head of the user USR, and therefore, by providing the transmitter TRM and the receiver RCV in the attachment unit HE, it is possible to acquire information on one or both of the blood flow velocity and pulse wave (blood pressure) of the blood vessels in the head from the blood vessels.

[0099] <Configuration Example 1> Next, a configuration example of the above-described electronic device HMD will be described.

[0100] 6 is a block diagram showing an example of the configuration of an electronic device HMD according to one aspect of the present invention. The electronic device HMD includes, as an example, a transmitter TRM, a receiver RCV, a peripheral circuit PH, a display DSP, and an audio output SNO. For purposes of illustrating the example configuration, FIG. 6 also illustrates a user USR and the user USR's eyes ME and ears ER.

[0101] In the electronic device HMD, the transmitter unit TRM has a vibrator OSC, a mixer UPCMX, and an ultrasonic transmission circuit USC. The receiver unit RCV has a vibrator OSCr, a mixer DNCMX, and a functional circuit FNC. The peripheral circuit PH has a voltage waveform generating circuit VWC, a drive circuit DRV, an acoustic processing circuit (sometimes called a sound board) SNBD, and a control circuit CTRL.

[0102] The control circuit CTRL has a function of controlling each circuit included in the electronic device HMD, for example. Therefore, the control circuit CTRL is electrically connected to the transmitter TRM, the receiver RCV, the voltage waveform generating circuit VWC, the sound processing circuit SNBD, etc. Also, the control circuit CTRL has a function of processing information transmitted from each circuit included in the electronic device HMD and transmitting the processing results to a predetermined circuit, for example.

[0103] For example, the ultrasonic transmission circuit USC has a function of generating a high-frequency electrical signal and a function of transmitting the electrical signal to a mixer UPCMX (described later). The ultrasonic transmission circuit USC may also have a function of transmitting the electrical signal to the control circuit CTRL. The electrical signal transmitted to the control circuit CTRL may be an analog voltage or may be converted to a digital voltage (digital value). The converted digital voltage electrical signal may be a voltage corresponding to information such as the frequency of the ultrasonic waves generated by the ultrasonic transmission circuit USC. In this specification, the electrical signal transmitted from the ultrasonic transmission circuit USC to the control circuit CTRL is referred to as a first electrical signal.

[0104] The voltage waveform generating circuit VWC has a function of generating a signal for converting the waveform of the electrical signal generated by the ultrasonic transmission circuit USC, for example. This conversion is performed by a mixer UPCMX, which will be described later. The voltage waveform generating circuit VWC can be, for example, a circuit for generating timing pulses or a local oscillator.

[0105] The mixer UPCMX has the function of mixing the high-frequency electrical signal generated by the ultrasonic transmission circuit USC with the electrical signal generated by the voltage waveform generation circuit VWC, and transmitting the mixed electrical signal to the oscillator OSC.

[0106] The oscillator OSC has a function of generating an ultrasonic wave USW based on the voltage waveform of the electrical signal mixed by the mixer UPCMX when the electrical signal is input to the oscillator OSC. The ultrasonic wave USW propagates to the eye of the user USR.

[0107] The oscillator OSCr has the function of receiving ultrasound USWr reflected by blood cells contained in either or both of the retinal blood vessels in the eye ME of the user USR and the blood vessels contained in the fundus, and generating an electrical signal corresponding to the ultrasound USWr.

[0108] Like the mixer UPCMX, the mixer DNCMX has the function of mixing the electrical signal generated by the oscillator OSCr and the electrical signal generated by the voltage waveform generating circuit VWC and transmitting the mixed electrical signal to the functional circuit FNC.

[0109] Depending on the situation, the electronic device HMD may be configured not to include one or more selected from the voltage waveform generating circuit VWC, the mixer UPCMX, and the mixer DNCMX.

[0110] The functional circuit FNC may be a circuit having one or more components selected from a band-pass filter, an amplifier, and an analog-to-digital conversion circuit, and has the function of acquiring an electrical signal from the mixer DNCMX, processing the electrical signal using the above-mentioned circuit, and transmitting the processed electrical signal to the control circuit CTRL.

[0111] A bandpass filter has a function of, for example, outputting an AC voltage in a specific frequency band to its output terminal, and also has a function of attenuating AC voltages outside the specific frequency band. In other words, the bandpass filter can select one or more channels from an electrical signal having multiple channels by determining the specific frequency band to be output to its output terminal.

[0112] The amplifier has a function of amplifying, for example, the voltage amplitude of an electrical signal.

[0113] The analog-to-digital conversion circuit has a function of converting, for example, an electrical signal into a digital signal.

[0114] In this specification, the electrical signal transmitted from the oscillator OSCr to the mixer DNCMX, the electrical signal transmitted from the mixer DNCMX to the functional circuit FNC, and the electrical signal transmitted from the functional circuit FNC to the control circuit CTRL are collectively referred to as the second electrical signal.

[0115] The second electrical signal output from the functional circuit FNC is transmitted to the control circuit CTRL. The control circuit CTRL obtains information such as the frequency of the ultrasound USW from the first electrical signal and information such as the frequency of the ultrasound USWr from the second electrical signal, and uses this information to calculate the blood flow velocity or pulse wave (blood pressure) measured in the blood vessels at the eye ME of the user USR. The control circuit CTRL then transmits the calculation result as an electrical signal to one or both of the display unit DSP and the audio output unit SNO.

[0116] Specifically, for example, when the results of processing performed by the control circuit CTRL (blood flow velocity or pulse wave (blood pressure)) are to be displayed on the display unit DSP, the control circuit CTRL converts the results into an appropriate electrical signal (referred to herein as a third electrical signal) and transmits the third electrical signal to the display unit DSP via the drive circuit DRV. The display unit DSP then displays an image PIC1 corresponding to the electrical signal to the eye ME of the user USR. Furthermore, for example, when the results of processing performed by the control circuit CTRL are to be output as sound by the audio output unit SNO, the control circuit CTRL converts the results (blood flow velocity or pulse wave (blood pressure)) into an appropriate electrical signal (referred to herein as a fourth electrical signal) and transmits the fourth electrical signal to the audio output unit SNO via the acoustic processing circuit SNBD (described later). The audio output unit SNO then outputs sound VM corresponding to the electrical signal to the ear ER of the user USR.

[0117] By configuring the electronic device HMD as described above, the electronic device HMD can measure one or both of the blood flow velocity and pulse wave (blood pressure) of the user USR. Furthermore, the user USR can know one or both of his or her own blood flow velocity and pulse wave through the electronic device HMD.

[0118] <Configuration Example 2> Note that the configuration of the electronic device of one embodiment of the present invention is not limited to the configuration example of the electronic device HMD illustrated in Fig. 6. The configuration of the electronic device of one embodiment of the present invention may be changed as appropriate within the scope of solving the problem.

[0119] The electronic device HMD shown in Fig. 7 is configured by adding a sensor IS, a sensor control circuit GPC, and an interface IF to the electronic device HMD shown in Fig. 6. Fig. 7 also shows an external terminal EXPC and an observer OBS.

[0120] The peripheral circuit PH includes, for example, a sensor control circuit GPC and an interface IF.

[0121] The control circuit CTRL is electrically connected to the sensor control circuit GPC, which is electrically connected to the sensor IS. The control circuit CTRL is also electrically connected to the interface IF.

[0122] The sensor IS may be, for example, an imaging device (sometimes referred to as an image sensor). In this case, the sensor IS has a function of, for example, capturing an image of the user USR's eye ME or its fundus and acquiring the captured image as an image PIC2. The sensor IS also has a function of, for example, transmitting the image PIC2 to the sensor control circuit GPC. By configuring the electronic device HMD to have a sensor IS including an imaging device, it is possible to monitor the state of the fundus of the user USR's eye ME using ultrasound, as well as the blood flow velocity of at least one of the blood vessels around the user USR's eye ME, the retinal blood vessels MKN, and the blood vessels included in the fundus.

[0123] The sensor IS may be, for example, a temperature sensor. In this case, the sensor IS may measure, for example, the body temperature of the user USR. In the electronic device HMD of FIG. 7 , the sensor IS is configured to acquire the body temperature of the user USR from the eyes ME. However, if the sensor IS is a temperature sensor, the body temperature of the user USR may be acquired not only from the eyes ME but also from one or both of the ears ER and the skin.

[0124] The sensor control circuit GPC has a function of controlling the sensor IS. The sensor control circuit GPC has a function of driving the sensor IS, for example, by receiving a command signal from the control circuit CTRL. The sensor control circuit GPC may also have a current-voltage conversion circuit, an analog-digital conversion circuit, etc. For example, when information is acquired from the driven sensor IS and an analog current corresponding to the information is supplied to the sensor control circuit GPC, the sensor control circuit GPC can convert the analog current into an analog voltage using the current-voltage conversion circuit, and can also convert the analog voltage into a digital value using the analog-digital conversion circuit.

[0125] The interface IF has a function of transmitting and receiving information to and from an external terminal EXPC located outside the electronic device HMD, for example. The interface IF can be, for example, an input / output terminal. The interface IF may also be configured to perform wireless communication between the electronic device HMD and the external terminal EXPC using, for example, a radio frequency (RF) circuit.

[0126] 7 also illustrates, as an example, a case in which the monitor OBS uses the external terminal EXPC. In particular, by transmitting one or more pieces of information selected from the blood pressure, pulse, blood oxygen saturation, and body temperature of the user USR wearing the electronic device HMD to the external terminal EXPC via the interface IF, the monitor OBS can learn the information of the user USR. This allows the monitor OBS to know the physical condition of the user USR. In other words, by constructing a system including the electronic device HMD and the external terminal EXPC as shown in FIG. 7, the monitor OBS can manage and understand the physical condition of the user USR.

[0127] 7 can be applied, for example, in an educational setting such as a school, where the user USR is a student and the monitor OBS is a teacher, allowing the teacher to manage and understand the physical condition of the students during class. Also, in a workplace, where the user USR is a subordinate and the monitor OBS is a boss, allowing the boss to understand and manage the physical condition of the subordinate during work.

[0128] <Configuration Example 3> In the above configuration example, an electronic device HMD has been described in which the sensor IS is an image sensor, a temperature sensor, etc., but the electronic device HMD can also be configured to have a sensor that uses an NV (Nitrogen Vacancy) center.

[0129] An example of a sensor using NV centers is a sensor having a diamond layer containing NV centers, which can be used as a composite sensor such as a magnetic sensor, an electric field sensor, and / or a temperature sensor.

[0130] Fig. 8 shows an example of the configuration of an electronic device HMD having a sensor using an NV center. The electronic device HMD of Fig. 8 is configured by adding a sensor NVS using an NV center to the electronic device HMD of Fig. 7. The peripheral circuit PH of the electronic device HMD of Fig. 8 includes a sensor control circuit NVC that has the function of controlling the sensor NVS. Note that in Fig. 8, the transmitter TRM and receiver RCV are collectively illustrated as an ultrasonic sensor USS.

[0131] The sensor NVS is described as having, for example, a diamond layer containing NV centers, and therefore functions as a sensor for detecting one or more selected from magnetic fields, electric fields, and temperature.

[0132] The sensor NVS has a function of detecting, for example, information on the body temperature of the skin SK of the user USR. The sensor NVS may also have a function of detecting information on the magnetic field and electric field emitted from the cells of the skin SK. In this specification, the above-mentioned information is collectively referred to as information TME.

[0133] Furthermore, the information TME detected by the sensor NVS is transmitted to the sensor control circuit NVC. The sensor control circuit NVC, for example, has the function of converting the information acquired by the sensor NVS into an appropriate electrical signal and transmitting it to the control circuit CTRL. Examples of the appropriate electrical signal conversion include analog-to-digital conversion, which converts an analog current or an analog voltage into a digital voltage. Therefore, the sensor control circuit NVC may include an analog-to-digital conversion circuit.

[0134] <<Configuration Example of Composite Sensor>> FIG. 9A shows an embodiment of a semiconductor device that functions as a composite sensor having a diamond layer with NV centers.

[0135] 9 is, for example, a PIN (p-intrinsic-n) diode and includes an n-positive layer 810, a p-negative layer 820, a p-positive layer 830, and electrodes 840a and 840b. The semiconductor device 800 includes at least carbon and nitrogen. Alternatively, the semiconductor device 800 may be a PN junction diode or a field effect transistor.

[0136] The n-plus layer 810 is a semiconductor such as diamond containing impurities such as arsenic or phosphorus at a concentration of a predetermined value or more (for example, 8×10 １９ cm −３ The thickness of the n-plus layer 810 is, for example, 500 nm, and is set appropriately depending on the electrical characteristics required for the semiconductor device 800.

[0137] The p-negative layer 820 is formed by adding impurities such as boron to a semiconductor such as diamond at a concentration lower than a predetermined value (for example, 2×10 １４ cm −３ ) doped semiconductor. The thickness of the p-negative layer 820 is 5 μm, and is set appropriately depending on the electrical characteristics required of the semiconductor device 800. The p-negative layer 820 also has a sensor section 850 formed in a layer shape containing a diamond NV center by, for example, ion implantation of nitrogen ions. For example, the sensor section 850 is preferably located at a depth of 300 nm to 400 nm from the junction surface that joins with the n-positive layer 810, and more preferably located at a depth of approximately 350 nm.

[0138] Semiconductors such as diamond can be synthesized by a high pressure and high temperature (HPHT) method, a CVD method, or a detonation method.

[0139] When microwaves are applied to the sensor unit 850 having the NV center, the fluorescence emitted by the NV center changes depending on one or more selected from the electric field, temperature, and magnetic field. Therefore, based on the microwave frequency at which the intensity of the fluorescence emitted by the NV center decreases, one or more selected from the electric field, temperature, and magnetic field inside the semiconductor device 800 at the position where the sensor unit 850 is placed can be measured.

[0140] The p-positive layer 830 is formed by adding impurities such as boron to a semiconductor such as diamond at a concentration of a predetermined value or more (for example, 1×10 １７ cm −３The thickness of the p-positive layer 830 is 500 μm, and is set appropriately depending on the electrical characteristics required for the semiconductor device 800.

[0141] The electrodes 840 a and 840 b apply a voltage supplied from a power supply external to the semiconductor device 800 to the semiconductor device 800 .

[0142] Fig. 9B shows an example of a measurement device that measures physical parameters in the semiconductor device 800 shown in Fig. 9A. The measurement device 900 shown in Fig. 9B may be, for example, a laser confocal microscope, and includes the semiconductor device 800, a laser light source 910, a beam splitter 920, an objective lens 930, a slide glass 940, a power source 950, a microwave source 960, a detection device 970, and a control device 980. Note that the measurement device 900 may also include a digital camera or a spectrometer.

[0143] The laser light source 910 emits laser light with a wavelength of, for example, 532 nm that excites the NV center of the sensor unit 850 disposed in the semiconductor device 800 shown in FIG. 9A.

[0144] The beam splitter 920 reflects the laser light emitted from the laser light source 910 in the direction of the semiconductor device 800. The beam splitter 920 also transmits the fluorescent light beam emitted by the sensor unit 850 of the semiconductor device 800 and emits it toward the detection device 970.

[0145] The objective lens 930 adjusts the beam width of the laser light emitted from the laser light source 910 and irradiates the laser light onto the semiconductor device 800. The objective lens 930 also collimates the fluorescence emitted by the sensor unit 850 in the semiconductor device 800 and emits the parallel light toward the detection device 970.

[0146] The slide glass 940 is made of quartz glass or the like, and has the semiconductor device 800 to be measured placed on it. Electrodes are formed on the surface of the slide glass 940 on the side where the semiconductor device 800 is placed, and wiring is provided for operating the semiconductor device 800. A microwave wire including an antenna for irradiating microwaves emitted by a microwave source 960 to the semiconductor device 800 is provided on the slide glass 940 on the side where the semiconductor device 800 is placed.

[0147] The power supply 950 supplies power of several tens or several hundreds of volts to the semiconductor device 800 placed on the slide glass 940 based on a control instruction from the control device 980 .

[0148] The microwave source 960 is a radio wave transmitting device that emits microwaves in a predetermined frequency range centered around 2.87 GHz. The microwave source 960 irradiates the emitted microwaves to the semiconductor device 800 via an antenna disposed on the slide glass 940, causing the NV center of the sensor unit 850 to enter an ESR (Electron Spin Resonance) state.

[0149] The laser light source 910 and the microwave source 960 operate as a driving unit that drives the sensor unit 850 .

[0150] The detection device 970 has, for example, an APD (avalanche photodiode), receives the fluorescence emitted by the sensor unit 850, and detects the intensity of the received fluorescence for each position on the XY plane. The detection device 970 outputs the detected fluorescence intensity for each position on the XY plane to the control device 980. The spatial resolution of the detection device 970 is determined by the focus of the laser light by the objective lens 930 and the accuracy of the sample holder (piezo scanner) that fixes the semiconductor device 800 on the slide glass 940, and is preferably in the range of 10 nm to 300 nm. The detection device 970 may also perform imaging measurements using an imaging device including one or both of a CCD (charge coupled device) image sensor and a CMOS (complementary metal oxide semiconductor) image sensor.

[0151] The control device 980 is a computer device including an arithmetic processing device (an example of which is a processor) and a storage device (an example of which is a hard disk drive), and controls the operation of each element of the measurement device 900. For example, the control device 980 controls the voltage applied to the semiconductor device 800 by the power supply 950 and the frequency of the microwaves emitted by the microwave source 960. The control device 980 also calculates the fluorescence intensity distribution for each position on the XY plane using the fluorescence intensity from the sensor unit 850 detected by the detection device 970. Based on the calculated intensity distribution, the control device 980 determines the frequency at which the intensity is lowest for each position on the XY plane. The control device 980 can then calculate one or more physical parameters selected from the electric field, magnetic field, and temperature for each position on the XY plane, for example, based on the data on the frequency at which the intensity is lowest for each position on the XY plane.

[0152] Furthermore, as described above, the control device 980 can be, for example, the sensor control circuit NVC in the configuration example of the electronic device HMD in Fig. 8. Alternatively, the control device 980 can be, for example, a circuit provided with a memory device or the like in addition to the sensor control circuit NVC in the configuration example of the electronic device HMD in Fig. 8.

[0153] <Configuration Example 4> The electronic device HMD shown in Fig. 10 is a modified example of the electronic device HMD of Fig. 8, and is configured such that a display unit DSP, an ultrasonic sensor USS, a sensor IS, and a sensor NVS are included in the display device DEV. Also, while the electronic device HMD of Fig. 10 is configured such that the display device DEV includes the display unit DSP, the ultrasonic sensor USS, the sensor IS, and the sensor NVS, the display device DEV may also be configured such that it includes one or more selected from the ultrasonic sensor USS, the sensor IS, and the sensor NVS. Specifically, for example, the display device DEV may be configured such that it includes the display unit DSP and the sensor IS, or may also be configured such that it includes the display unit DSP and the sensor NVS.

[0154] Here, we will explain a configuration example of a display device DEV that can be provided in the electronic device HMD of Fig. 10. The display device DEV shown in Fig. 11 is an example of a display device DEV that can be provided in the electronic device HMD of Fig. 10, and has substrates with circuits mounted above and below a substrate BS. As an example, the display device DEV shown in Fig. 11 has a circuit layer SICL, a wiring layer LINL, a display unit DSP, a transmitter unit TRM, and a receiver unit RCV above the substrate BS, and has a sensor NVS below the substrate BS.

[0155] The substrate BS can be, for example, a single-crystal substrate (e.g., a semiconductor substrate made of silicon or germanium). In addition to single-crystal substrates, the substrate BS can be, for example, an SOI (Silicon-On-Insulator) substrate, a glass substrate, a quartz substrate, a plastic substrate, a sapphire glass substrate, a metal substrate, a stainless steel substrate, a substrate having stainless steel foil, a tungsten substrate, a substrate having tungsten foil, a flexible substrate, a laminated film, paper containing a fibrous material, or a base film. Examples of glass substrates include barium borosilicate glass, aluminoborosilicate glass, and soda-lime glass. Examples of flexible substrates, laminated films, or base films include the following: Plastics such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), and polytetrafluoroethylene (PTFE). Another example is a synthetic resin such as an acrylic resin. Other examples include polypropylene, polyester, polyvinyl fluoride, and polyvinyl chloride. Other examples include polyamide, polyimide, aramid, epoxy resin, inorganic vapor deposition film, and paper. Note that if the manufacturing process of the display device DEV includes a heat treatment, it is preferable to select a material with high heat resistance for the substrate BS.

[0156] The circuit layer SICL is provided on the substrate BS. The circuit layer SICL includes, for example, a drive circuit DRV for driving the display unit DSP, a sensor control circuit GPC for controlling the sensor IS, a sensor control circuit NVC for controlling the sensor NVS, and a control circuit CTRL.

[0157] In this embodiment, the substrate BS is described as a semiconductor substrate made of silicon, and therefore, the transistors included in the circuit layer SICL can be transistors having silicon in their channel formation regions (hereinafter referred to as Si transistors).

[0158] The wiring layer LINL is provided on the circuit layer SICL, and the display unit DSP, the transmitter unit TRM, and the receiver unit RCV are provided on the wiring layer LINL. The display unit DSP, the transmitter unit TRM, and the receiver unit RCV can be mounted on the wiring layer LINL of the substrate BS by, for example, a bonding process. The bonding process will be described in detail in embodiment 3.

[0159] The wiring layer LINL is provided with wiring, for example. The wiring included in the wiring layer LINL functions as wiring that electrically connects, for example, each circuit included in the circuit layer SICL provided below with the display unit DSP, the transmitter unit TRM, and the receiver unit RCV provided above.

[0160] In the configuration of the display device DEV in FIG. 11, a transmission unit TRM, a display unit DSP, and a reception unit RCV are arranged in this order.

[0161] 11, the display unit DSP includes a pixel 80. As an example, the pixel 80 has a light-emitting device 150R, a light-emitting device 150G, a light-emitting device 150B, and a light-receiving device 160. In particular, the sensor IS described above can be the light-receiving device 160 shown in FIG.

[0162] The configuration of the pixel 80 will be described in detail in the third embodiment.

[0163] The sensor NVS is provided below the substrate BS, for example. The sensor NVS can be mounted below the substrate BS by, for example, a bonding process.

[0164] In addition, when the sensor NVS is provided below the substrate BS, the sensor NVS may function, for example, as a temperature sensor that detects the temperature of the substrate BS. For example, when the display device DEV is driven for a long period of time, the temperature of the display device DEV may rise due to heat generated during operation of the display device DEV. In this case, by using the sensor NVS as a temperature sensor, the sensor NVS can detect the increased temperature. Furthermore, by providing the display device DEV with a function that, when the sensor NVS detects an increase in the temperature of the display device DEV, limits the amount of power supplied to the display device DEV or temporarily suspends the circuits included in the display device DEV, it is possible to prevent failure of the electronic device HMD, particularly the display device DEV, due to heat.

[0165] <Structure Example 5> FIG. 12A illustrates a structure example of a display device that can be applied to an electronic device of one embodiment of the present invention.

[0166] 12A includes a substrate BS, a circuit layer SICL provided on the substrate BS, a wiring layer LINL provided on the circuit layer SICL, and a display unit DSP provided on the wiring layer LINL. Note that the substrate BS, the circuit layer SICL, the wiring layer LINL, and the display unit DSP are described in reference to the display device DEV in FIG. 11 .

[0167] 12A, the display unit DSP has a region DSPPX, a region DSPa, and a region DSPb. Note that the display unit DSP has a light-emitting device and a light-receiving device, similar to the display device DEV of FIG.

[0168] Furthermore, sensor NVSa is provided in an area overlapping region DSPa, and sensor NVSb is provided in an area overlapping region DSPb. The area located between sensors NVSa and NVSb and overlapping region DSPPX is referred to as region OPA. Region OPA functions as a region for emitting light (image PIC1 is shown in FIG. 12A ) from a light-emitting device included in region DSPPX upward.

[0169] The sensor NVSa and the sensor NVSb may be at least one of a sensor having an NV center or a circuit included in a sensor having an NV center, as described in Configuration Example 3. For example, the sensor NVSa and the sensor NVSb may be the semiconductor device 800 and the slide glass 940 included in the measuring device 900.

[0170] When the sensors NVSa and NVSb are driven, light emitted from light-emitting devices included in the regions DSPa and DSPb of the display unit DSP is incident on the sensors NVSa and NVSb. That is, in the display device DEV shown in FIG. 12A , the light-emitting devices included in the regions DSPa and DSPb of the display unit DSP correspond to the laser light source 910 in the measurement device 900.

[0171] Furthermore, when sensors NVSa and NVSb are driven, fluorescence emitted from sensors NVSa and NVSb (specifically, sensor units 850 included in sensors NVSa and NVSb, respectively) is received by light receiving devices included in regions DSPa and DSPb of display unit DSP. That is, in the display device DEV shown in FIG. 12A , the light receiving devices included in regions DSPa and DSPb of display unit DSP correspond to detection device 970 in measurement device 900.

[0172] Furthermore, it is preferable that light-shielding walls be provided between the regions DSPa and DSPPX and between the regions DSPb and DSPPX to prevent light from entering each other's regions, so that light emitted by the light-emitting devices included in the region DSPPX does not enter at least one of the sensors NVSa and NVSa, and so that light emitted by the light-emitting devices included in the regions DSPa and DSPb does not enter the region OPA. As an example, the display device DEV of Fig. 12A has light-shielding walls SKWa and SKWb provided between the regions DSPa and DSPPX and between the regions DSPb and DSPPX, respectively. In Fig. 12A, the walls SKWa and SKWb are each indicated by a thick, two-dot chain line.

[0173] Furthermore, in the display device DEV of FIG. 12A, the light emitting device and the light receiving device are included in the same region (region DSPa or region DSPb), and therefore the beam splitter 920 does not need to be provided.

[0174] 12A does not show the objective lens 930, but the display device DEV of Fig. 12A may be provided with the objective lens 930. The objective lens 930 can be provided, for example, between the region DSPa of the display unit DSP and the sensor NVSa, and between the region DSPb of the display unit DSP and the sensor NVSb.

[0175] 12A may be provided with a lens for viewing the image PIC1 displayed on the display unit DSP. The lens may be provided, for example, in a region DSPPX of the display unit DSP and in a region overlapping the region OPA.

[0176] Fig. 12B shows an example of a front view (zx plan view seen from the y direction) when the display device DEV of Fig. 12A is applied to the electronic device HMD of Fig. 1, Fig. 5, etc. The electronic device HMD shown in Fig. 12B is configured to include a display device DEV for the right eye and a display device DEV for the left eye.

[0177] Furthermore, the display devices DEV for the right eye and the left eye each have a sensor NVSa and a sensor NVSb, which are preferably positioned so as to come into contact with the periphery of the eye ME of the user USR, for example.

[0178] The positions of the sensors NVSa and NVSb included in the display devices DEV for the right and left eyes, respectively, are not limited to those of the electronic device HMD shown in Fig. 12B, and may be arranged such that the sensor NVSa, display unit DSP, and sensor NVSb are aligned above and below the eye ME (in the z direction), as in the electronic device HMD shown in Fig. 12C, for example. Furthermore, the positions of the sensors NVSa and NVSb included in the display devices DEV for the right and left eyes, respectively, are not limited to those shown in Fig. 12B and 12C, and may be determined arbitrarily.

[0179] Also, in Figures 12A to 12C, two sensors, NVSa and NVSb, are illustrated for the display device DEV, but the number of sensors having NV centers that the display device DEV has may be one, or may be three or more.

[0180] By configuring the electronic device HMD shown in Figures 12B and 12C using the display device DEV shown in Figure 12A, it is possible to measure the body temperature around the eye ME of a user USR wearing the electronic device HMD.

[0181] Furthermore, although not shown, by combining the display device DEV shown in Figures 12A to 12C with the ultrasonic sensor USS (transmitter unit TRM and receiver unit RCV) and sensor IS described in the above configuration example, it is possible to measure not only the body temperature around the eye ME of the user USR, but also one or more selected from the blood flow velocity, pulse, blood pressure, and blood oxygen saturation of the eye ME of the user USR.

[0182] In the present embodiment, an electronic device has been described that uses a transmitter TRM and a receiver RCV to acquire information on one or both of blood flow velocity and pulse wave (blood pressure) using ultrasound. However, the electronic device of one aspect of the present invention is not limited to this. The electronic device of one aspect of the present invention may use, instead of ultrasound, a light-emitting device such as an LED or organic EL and an imaging device. Specifically, for example, the light-emitting device may irradiate light onto the capillaries to be measured, and the capillaries imaged by the light may be captured by the imaging device, and information on one or both of pulse wave (blood pressure) and blood oxygen saturation may be acquired from the captured image.

[0183] The configuration examples described in this embodiment can be combined with each other as appropriate.

[0184] This embodiment mode can be appropriately combined with other embodiment modes described in this specification.

[0185] Embodiment 2 In this embodiment, application examples of electronic devices according to one embodiment of the present invention will be described with reference to FIGS.

[0186] <Usage Example 1> Fig. 13 shows a situation in which a distance learning class is being conducted using electronic devices 1010 (electronic devices 1010a and 1010b) and either or both of electronic devices 1020 and 1021. Note that Fig. 13 illustrates a situation in which teacher 1025, student 1015a, and student 1015b are participating in the distance learning class, but the number of students participating in the distance learning class may be three or more. In this case, each student uses an electronic device 1010, and therefore three or more electronic devices 1010 are used in the distance learning class.

[0187] Fig. 13 shows a teacher 1025 teaching a lesson in a classroom or the like using electronic devices 1020, 1021, and a camera 1022. Here, the electronic device 1020 corresponds to the electronic device HMD shown in Fig. 1A or the like. Note that Fig. 13 shows the teacher 1025 using the electronic devices 1020 and 1021, but the electronic device used by the teacher 1025 may be either the electronic device 1020 or the electronic device 1021.

[0188] Image data is generated by capturing images of the lesson using a camera 1022. The image data includes the teacher 1025 and his surroundings. The surroundings of the teacher 1025 include, for example, a blackboard, a whiteboard, or an electronic blackboard. The image data is transmitted via a network 1030 to one or more electronic devices used by the student 1015a (e.g., the electronic device 1010a and an electronic device equipped with a display device 1011, which will be described later) and one or more electronic devices used by the student 1015b (e.g., the electronic device 1010b).

[0189] 13, the lesson is photographed using the camera 1022, but it may be photographed using a camera provided in the electronic device 1021. In this case, the teacher 1025 only needs to use at least the electronic device 1021.

[0190] 13 shows a situation in which a student 1015a is taking a class at home or the like using an electronic device 1010a and an electronic device (not shown in FIG. 13) including a display device 1011. Here, the electronic device 1010a corresponds to the HMD electronic device shown in FIG. 1A or the like. The electronic device including the display device 1011 receives the image data via a network 1030, and the image data is displayed on the display device 1011. The student 1015a can take the class by visually viewing the image data displayed on the display device 1011 via the electronic device 1010a.

[0191] The electronic device 1010a can measure one or more of the blood pressure, pulse, oxygen saturation, and body temperature of the student 1015a. The information on one or more of the blood pressure, pulse, oxygen saturation, and body temperature of the student 1015a is transmitted via the network 1030 to one or more of the electronic devices (e.g., the electronic device 1020 and the electronic device 1021) used by the teacher 1025.

[0192] 13 shows a situation in which a student 1015b is taking a class at home or the like using an electronic device 1010b. Here, the electronic device 1010b corresponds to the electronic device HMD shown in FIG. 1A and the like, and the display unit of the electronic device 1010b corresponds to the display unit DSP shown in FIG. 1A and the like. The electronic device 1010b receives the image data via the network 1030. The student 1015b can take the class by visually checking the image data displayed on the display unit of the electronic device 1010b.

[0193] The electronic device 1010b can measure one or more of the blood pressure, pulse, oxygen saturation, and body temperature of the student 1015b. Information on one or more of the blood pressure, pulse, oxygen saturation, and body temperature of the student 1015b is transmitted via the network 1030 to one or more of the electronic devices (e.g., the electronic device 1020 and the electronic device 1021) used by the teacher 1025.

[0194] The electronic device 1020 receives information transmitted from each of the electronic devices 1010a and 1010b, and displays the information on a display unit of the electronic device 1020. Alternatively, the electronic device 1021 receives information transmitted from each of the electronic devices 1010a and 1010b, and displays the information on a display unit of the electronic device 1021. The teacher 1025 can check the status of the students 1015a and 1015b by visually checking the information displayed on the display unit of the electronic device 1020 or the display unit of the electronic device 1021.

[0195] As described above, distance learning can be conducted by transmitting and receiving data between electronic device 1010 and electronic device 1020. At this time, student 1015a and student 1015b can attend the lesson while being aware of their own health conditions. Furthermore, teacher 1025 can conduct the lesson while checking the condition of student 1015a and student 1015b.

[0196] Next, examples of displays on the display units of the electronic devices used by the students are shown in FIGS. 14A to 14C and 15. FIG.

[0197] 14A shows the real space viewed by student 1015a. Student 1015a views display device 1011, a notebook, and a pencil. Student 1015a also views image data 1026 displayed on display device 1011. The image data 1026 is image data generated by capturing an image with camera 1022. The image data 1026 includes an image of teacher 1025 and the surrounding area.

[0198] 14B shows image data displayed on the display unit 1012 of the electronic device 1010a used by the student 1015a. The display unit 1012 displays one or more pieces of information selected from the blood pressure, pulse rate, oxygen saturation, and body temperature of the student 1015a measured by the electronic device 1010a. For example, as shown in FIG. 14B, the display unit 1012 displays an image 1016a1 including the systolic blood pressure, diastolic blood pressure, and pulse rate of the student 1015a.

[0199] Note that information other than the blood pressure, pulse, oxygen saturation, and body temperature of student 1015a may be displayed on display unit 1012. For example, if student 1015a has a high level of eye fatigue, electronic device 1010 may determine this and display image 1016a2 on display unit 1012, the image 1016a2 including a character string appropriate for student 1015a (in FIG. 14B , "Let's try our best for another 10 minutes").

[0200] 14C illustrates the real space viewed by student 1015a via display unit 1012 of electronic device 1010a. In addition to display device 1011, a notebook, and a pencil, student 1015a is also viewing images 1016a1 and 1016a2. This configuration allows student 1015a to recognize not only the state of the remote class being delivered but also his or her own health condition. Furthermore, by recognizing the character string included in image 1016a2, student 1015a can regain focus on the remote class.

[0201] The electronic device 1010a may have a function for estimating the gaze direction of a user (e.g., student 1015a). By having this function, the electronic device 1010a can place the image 1016a1 and the image 1016a2 in a space where the gaze of the student 1015a is not focused, as shown in FIG. 14C . This can prevent the student 1015a from losing concentration on the remote class.

[0202] Furthermore, the electronic device 1010a having the above function can detect a period during which the student's gaze is averted from the image data 1026. For example, if the period is long, the electronic device 1010a can output a character string appropriate for the student 1015a as voice or output a warning sound, thereby enabling the student 1015a to regain concentration on the distance learning.

[0203] The gaze direction of a user (e.g., student 1015a) may be recognized using an electronic device 1010a equipped with multiple electrodes capable of detecting current flowing in association with the movement of the user's eyeball. The gaze direction of a user (e.g., student 1015a) may also be estimated using a method utilizing one or both of blinking and eyelid movement, a method utilizing the movement of the pupil, or a scleral reflex method. Alternatively, the gaze direction of a user (e.g., student 1015a) may be estimated using a trained model or an arithmetic circuit capable of arithmetic processing based on an artificial neural network (ANN). Note that, in this specification, an artificial neural network is referred to as a neural network. A neural network is preferably used as the trained model, and a convolutional neural network is more preferably used. The arithmetic circuit is preferably an arithmetic circuit having a function of performing product-sum operations.

[0204] 15 shows image data displayed on the display unit 1012 of the electronic device 1010b used by the student 1015b. The student 1015b is viewing image data 1026 generated by capturing an image with the camera 1022. The image data 1026 includes an image of the teacher 1025 and the surrounding area. In addition, the image data 1026 has an image 1016b1 and an image 1016b2 superimposed thereon.

[0205] Image 1016b1 includes, for example, the systolic blood pressure, diastolic blood pressure, and pulse rate of student 1015b. Image 1016b2 includes, for example, a character string appropriate for student 1015b ("Let's try our best for another 10 minutes" in FIG. 15).

[0206] With this configuration, student 1015b can recognize his / her own health condition in addition to the state of the remote class delivered by the remote class. Also, student 1015b can regain concentration on the remote class by recognizing the character string included in image 1016b2.

[0207] The electronic device 1010b may have a function for estimating the gaze direction of the student 1015b. With this function, the electronic device 1010b can display an image 1016b1 and an image 1016b2 (in FIG. 15 , "Let's concentrate") on the display unit 1012 when the student 1015b is not concentrating on the lesson, as shown in FIG. 15 . When the student 1015b is not concentrating on the lesson, the student 1015b's gaze tends to be focused on a certain area of ​​the display unit 1012 for a long time. By estimating the gaze direction of the student 1015b, the electronic device 1010b can determine whether the student 1015b is concentrating on the lesson. When the student 1015b is not concentrating on the lesson, the electronic device 1010b can suppress a decrease in the student 1015b's concentration on the remote lesson by displaying an image 1016b2, as shown in FIG. 15 . In particular, it is preferable that image 1016b2 be displayed in an area of ​​display unit 1012 where the gaze of student 1015b is focused.

[0208] Next, examples of displays on the display unit of the electronic device used by the teacher are shown in FIGS. 16A, 16B, and 17A to 17C.

[0209] Next, FIGS. 16A and 16B show examples of the display on the display unit of the electronic device 1021 when the electronic device 1021 receives information transmitted from the electronic device 1010a and the electronic device 1010b.

[0210] 16A shows an example of a display on the display unit 1023 of the electronic device 1021 immediately after the start of the distance learning class. Also, FIG. 16B shows an example of a display on the display unit 1023 of the electronic device 1021 some time after the start of the distance learning class.

[0211] 16A and 16B, the display unit 1023 has an area 1013a and an area 1013b, and image data is displayed in each of the areas 1013a and 1013b.

[0212] The image displayed in area 1013a includes one or more pieces of information selected from the blood pressure, pulse rate, oxygen saturation, and body temperature of student 1015a measured by electronic device 1010a. For example, as shown in FIGS. 16A and 16B , area 1013a displays image 1016a1 including the systolic blood pressure, diastolic blood pressure, and pulse rate of student 1015a. Note that area 1013a may also display an image captured by a camera included in the electronic device equipped with display device 1011. In other words, area 1013a may display an image including student 1015a and its surroundings.

[0213] The image displayed in area 1013b displays one or more pieces of information selected from the blood pressure, pulse rate, oxygen saturation, and body temperature of student 1015b measured by electronic device 1010b. For example, as shown in Figures 16A and 16B, area 1013b displays image 1016b1 including the systolic blood pressure, diastolic blood pressure, and pulse rate of student 1015b. It is preferable to display an image ("1015b" in Figures 16A and 16B) that indicates that the information displayed in area 1013b is information about student 1015b.

[0214] Immediately after the distance learning begins, there is no change in the status of the students 1015a and 1015b. Therefore, as shown in Fig. 16A, an image 1016a1 and an image 1016b1 are displayed in the area 1013a and the area 1013b, respectively.

[0215] After a distance learning lesson has started, some users may experience high levels of eye fatigue. For example, if student 1015a experiences high levels of eye fatigue, image 1016a3 is displayed in area 1013a as shown in FIG. 16B . Image 1016a3 includes a character string. The character string may be, for example, "You may be sleepy" or "Your eyes appear to be tired."

[0216] Furthermore, some users may avert their gaze after a while has passed since the remote lesson began. For example, when student 1015b averts his or her gaze, image 1016b3 is displayed so as to overlap with area 1013b, as shown in FIG. 16B . Image 1016b3 includes a character string. Note that the character string may be, for example, "You tend to avert your gaze."

[0217] As described above, by using one embodiment of the present invention, the teacher 1025 can recognize the states of the students 1015a and 1015b as character string information. For example, the teacher 1025 can easily recognize students who have high eye fatigue or who are looking away from the class, among the students participating in the remote class, and can communicate closely with these students. In particular, when a remote class is held with a large number of students, each image displayed on the display unit 1023 becomes small, making it difficult to grasp the state of the user displayed on the display unit 1023. Therefore, one embodiment of the present invention can be suitably used for remote classes with a large number of students. Furthermore, the teacher 1025 can recognize the health state of a student attending a class using only the electronic device 1010, even if the teacher 1025 cannot see the facial expression of the student.

[0218] Next, FIGS. 17A to 17C show examples of displays on the display unit of the electronic device 1020 when the electronic device 1020 receives information transmitted from the electronic device 1010a and the electronic device 1010b.

[0219] 17A shows a real space viewed by a teacher 1025. The teacher 1025 views a blackboard (which may alternatively be, for example, a whiteboard or an electronic blackboard), an electronic device 1021, and the like.

[0220] 17B shows image data displayed on display unit 1027 of electronic device 1020 used by teacher 1025. Display unit 1027 displays one or more pieces of information selected from the blood pressure, pulse rate, oxygen saturation, and body temperature of student 1015a measured by electronic device 1010a, and one or more pieces of information selected from the blood pressure, pulse rate, oxygen saturation, and body temperature of student 1015b measured by electronic device 1010b. For example, FIG. 17B displays image 1016c including the systolic blood pressure, diastolic blood pressure, and pulse rate of each of students 1015a and 1015b.

[0221] The display unit 1027 may display information other than the blood pressure, pulse, oxygen saturation, and body temperature of each of the students 1015a and 1015b. For example, the image 1016c may display information indicating a student with a high level of eye fatigue. Furthermore, for example, the image 1016c may display information indicating a student who is looking away.

[0222] 17C shows a real space viewed by the teacher 1025 via the display unit 1027 of the electronic device 1020. The teacher 1025 is viewing the image 1016c in addition to the blackboard (which may alternatively be, for example, a whiteboard or an electronic blackboard), the electronic device 1021, etc. This configuration allows the teacher 1025 to recognize the health conditions of the students 1015a and 1015b. This allows for closer communication with the students.

[0223] The electronic device 1020 used by the teacher 1025 can measure one or more of the teacher 1025's blood pressure, pulse, oxygen saturation, and body temperature. One or more pieces of information selected from the teacher 1025's blood pressure, pulse, oxygen saturation, and body temperature may be transmitted via the network 1030 to an electronic device of a user who is not directly participating in the distance learning class. Examples of such a user include the teacher 1025's supervisor or colleague. The electronic device used by the user receives one or more pieces of information selected from the teacher 1025's blood pressure, pulse, oxygen saturation, and body temperature, and the information is displayed on a display unit of the electronic device. This allows the teacher 1025's supervisor to recognize the teacher 1025's state of tension, etc., and to provide guidance to the teacher 1025 taking the teacher 1025's state of tension, etc. into consideration. Furthermore, the teacher 1025's colleague can give the teacher 1025 advice on how to proceed with the class, etc., taking the teacher 1025's state of tension, etc. into consideration.

[0224] As described above, use of an electronic device of one embodiment of the present invention can enhance communication between teachers and students. Furthermore, communication between teachers can also be enhanced. Therefore, the electronic device of one embodiment of the present invention can be suitably used in the field of educational technology (also referred to as EdTech or EduTech). Note that EdTech may refer to a coined word combining education and technology.

[0225] Although the above example shows a distance learning session between a teacher and a student, a distance meeting may be held using electronic device 1010 (electronic device 1010a and electronic device 1010b), and / or electronic device 1020 and electronic device 1021.

[0226] Next, a method for estimating the degree of eye fatigue of the user and a method for estimating the direction of the line of sight of the user will be described.

[0227] As described above, methods for estimating the degree of eye fatigue of a user and methods for estimating the direction of the user's gaze include, for example, a method that uses one or both of blinking and eyelid movement, a method that uses movement of the pupil, or a scleral reflex method.

[0228] First, a method for detecting one or both of a blink and an eyelid movement of a user will be described with reference to FIG.

[0229] Near-infrared light is emitted from the electronic device. The near-infrared light is irradiated onto the user's eye or the area around the user's eye. The reflected near-infrared light is incident on the electronic device. This allows the state of the object to be detected.

[0230] 18 is a schematic diagram illustrating the user's eye and the area surrounding the user's eye. Fig. 18 shows the user's eyebrows 1960, the user's eyelids (upper eyelid 1966 and lower eyelid 1967), the user's eyelashes 1961, the user's pupils 1962, the user's cornea 1963, and the user's sclera 1965. The electronic device has a function of detecting one or more selected from the user's eyebrows 1960, the user's eyelids (upper eyelid 1966 and lower eyelid 1967), the user's eyelashes 1961, the user's pupils 1962, the user's cornea 1963, and the user's sclera 1965 shown in Fig. 18.

[0231] For example, an electronic device according to one embodiment of the present invention can detect the state of a user's eye or the area around the user's eye, as shown in FIG. 18 . For example, when a user closes their eyelids (upper eyelid 1966 and lower eyelid 1967), near-infrared light is irradiated onto the surface of the eyelids, i.e., onto the skin. When the eyelids are open, near-infrared light is irradiated onto the surface of the eyeball. Since the reflectance of the skin and the surface of the eyeball differs, the intensity of the reflected near-infrared light differs. By continuously monitoring the intensity of the reflected near-infrared light, the electronic device can detect one or both of the number of blinks and the time required for one blink.

[0232] When viewing a display for a long period of time, the number of blinks may decrease. Also, when a user becomes tired, the interval between blinks may become longer and the duration of each blink may become longer.

[0233] In an electronic device according to one embodiment of the present invention, the user's level of fatigue can be estimated from one or both of the number of blinks of the user and the time required for one blink. For example, the threshold value may be set so that if the number of blinks of the user in a certain period of time is equal to or less than a threshold value, the user's level of fatigue is determined to be high. Alternatively, the threshold value may be set so that if the time required for one blink of the user in a certain period of time is equal to or greater than a threshold value, the user's level of fatigue is determined to be high.

[0234] Next, a method utilizing the movement of the iris of the eye will be described. When a circular spot of infrared light is irradiated onto the boundary region between the cornea (e.g., cornea 1963 shown in FIG. 18 ) and the sclera (e.g., sclera 1965 shown in FIG. 18 ), the ratio of the area covering the cornea to the area covering the sclera changes as the eyeball moves within the irradiation range of the infrared light spot. Because the reflectance from the area covering the sclera is overwhelmingly greater than that from the area covering the cornea, the amount of reflected light changes as the eyeball moves. By measuring this change, it becomes possible to detect the direction in which the user is looking.

[0235] Next, the scleral reflex method will be described. Near-infrared light is emitted from an electronic device. This near-infrared light is irradiated onto the user's eye through an optical system. The reflected light passes through the optical system again and enters the electronic device. This makes it possible to detect the user's state. When viewing a displayed video, the gaze shifts when viewing a fast-moving object. When the gaze shifts, the eyeball moves. When the eyeball moves, the ratio of the area covered by the cornea irradiated with infrared light to the area covered by the sclera changes, so it is possible to monitor the reflected light component and detect the movement of the eyeball. That is, an electronic device according to one embodiment of the present invention has an eye tracking function. By detecting the user's gaze using the eye tracking function, the area the user is gazing at can be estimated.

[0236] In the above case, the electronic device preferably has a light-emitting device that emits infrared light (including near-infrared light).

[0237] Furthermore, the method for estimating the degree of eye fatigue of the user or the method for estimating the direction of the user's gaze may be performed using a trained model. As the trained model, it is preferable to use a neural network. As the neural network, it is particularly preferable to use deep learning. 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, a generative adversarial network (GAN), or the like.

[0238] Furthermore, a method for estimating the degree of eye fatigue of a user or the direction of the user's gaze may be performed using an arithmetic circuit capable of performing arithmetic processing based on a neural network. Note that an arithmetic circuit capable of performing arithmetic processing based on a neural network can be referred to as an arithmetic circuit having a function of performing product-sum operations. By using such an arithmetic circuit, image analysis can be performed with low power. In other words, the power consumption of an electronic device according to one embodiment of the present invention can be reduced.

[0239] Here, an arithmetic circuit will be described. The arithmetic circuit can be used, for example, as an arithmetic circuit having a function of performing a sum-of-products operation. The arithmetic circuit can also be used for arithmetic processing of a neural network. Note that an arithmetic circuit having a function of performing a sum-of-products operation can be rephrased as an arithmetic circuit of a neural network. As an example of the neural network, a hierarchical neural network can be applied. Note that the hierarchical neural network will be described later in this embodiment.

[0240] 19 illustrates an example of using an electronic device of one embodiment of the present invention in a medical setting. In particular, Fig. 19 illustrates a medical treatment using an electronic device 700 of one embodiment of the present invention and an endoscope device 710.

[0241] A doctor 712 operates an endoscope device 710 to observe the inside of a patient 715 and administer appropriate treatment. The doctor 712 wears an electronic device 700. Images captured by the endoscope device 710 are displayed in real time on the display unit of the electronic device 700, and the doctor 712 can administer treatment while viewing the images.

[0242] In addition, the image captured by the endoscope device 710 can also be displayed on a separately installed monitor device 711. This allows other doctors 713 and 714 to watch the procedure being performed by doctor 712 in real time without disturbing doctor 712. While an example in which the monitor device 711 is installed inside the operating room is shown here, it can also be viewed in a separate room. For example, a trainee can get a realistic feel for the atmosphere at the treatment site by watching the procedure being performed by doctor 712 on a monitor device installed in the operating room.

[0243] The display device of one embodiment of the present invention can be applied not only to the display portion of the electronic device 700 but also to the display portion of the monitor device 711. Therefore, the doctors 713 and 714 can make highly accurate medical decisions using images with extremely high resolution, and can share the decisions with the doctor 712 who is performing the treatment.

[0244] As described above, by using an electronic device according to one embodiment of the present invention, the quality of medical procedures performed by doctors can be improved. Therefore, the electronic device according to one embodiment of the present invention can be suitably used in the field of medical technology (also referred to as MedTech or MediTech). Note that MedTech may refer to a coined term combining medical and technology.

[0245] <<Hierarchical Neural Network>> As an example, a hierarchical neural network has one input layer, one or more intermediate layers (hidden layers), and one output layer, for a total of three or more layers. The hierarchical neural network ANN shown in FIG. 20A shows an example, and the neural network ANN has first to Rth layers (where R can be an integer equal to or greater than four). In particular, the first layer corresponds to the input layer, the Rth layer corresponds to the output layer, and the other layers correspond to intermediate layers. Note that FIG. 20A illustrates the (k-1)th layer and the kth layer (where k is an integer equal to or greater than three and equal to or less than R-1) as intermediate layers, and does not illustrate the other intermediate layers.

[0246] Each layer of the neural network ANN has one or more neurons. In FIG. 20A, the first layer has neurons N １ （１） Neuron N ｐ （１） (where p is an integer equal to or greater than 1), and the (k-1)th layer has neurons N １ （ｋ−１） Neuron N ｍ （ｋ−１） (where m is an integer equal to or greater than 1), and the kth layer has neurons N １ （ｋ） Neuron N ｎ （ｋ） (where n is an integer equal to or greater than 1), and the Rth layer has neurons N １ （Ｒ） Neuron N ｑ （Ｒ） (where q is an integer of 1 or greater).

[0247] In addition, in FIG. 20A, neuron N １ （１） , neuron N ｐ （１） , neuron N １ （ｋ−１） , neuron N ｍ （ｋ−１） , neuron N １ （ｋ） , neuron N ｎ （ｋ） , neuron N１ （Ｒ） , neuron N ｑ （Ｒ） In addition, the (k-1)th layer neuron N ｉ （ｋ−１） (where i is an integer between 1 and m), and the k-th layer neuron N ｊ （ｋ） (where j is an integer between 1 and n) are also shown, and other neurons are omitted from the illustration.

[0248] Next, we will explain the transmission of signals from neurons in the previous layer to neurons in the next layer, and the signals input and output to and from each neuron. ｊ （ｋ） Focus on.

[0249] FIG. 20B shows the k-th layer of neurons N ｊ （ｋ） and neuron N ｊ （ｋ） and the signal input to neuron N ｊ （ｋ） 20B shows the weight data w between the (k-1)th layer and the kth layer. １ （ｋ−１） ｊ （ｋ） , w ｉ （ｋ−１） ｊ （ｋ） , w ｍ （ｋ−１） ｊ （ｋ） , and the activation function f(u ｊ （ｋ） ) is shown.

[0250] Specifically, the (k-1)th layer neuron N １ （ｋ−１） Neuron N ｍ （ｋ−１） z １ （ｋ−１） ~z ｍ （ｋ−１） But neuron N ｊ （ｋ） The output is directed to the neuron Nｊ （ｋ） is z １ （ｋ−１） ~z ｍ （ｋ−１） Depending on z ｊ （ｋ） and generate z ｊ （ｋ） is output as an output signal to each neuron in the (k+1)th layer (not shown).

[0251] <<Configuration Example 1 of Achievement Circuit>> Next, a configuration example of an arithmetic circuit according to one embodiment of the present invention will be described.

[0252] The arithmetic circuit 1350 illustrated in FIG. 21 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].

[0253] 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.

[0254] 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].

[0255] The circuit WLD is electrically connected to the wirings WL[1] to WL[m] and the wirings WX1L[1] to WX1L[m]. The circuit XLD is electrically connected to the wirings WX1L[1] to WX1L[m].

[0256] The arithmetic circuit 1350 shown in Fig. 21 has circuits MP in which array units ALP are arranged in a matrix of m x n. Note that in Fig. 21, 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. 21 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.

[0257] 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].

[0258] 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].

[0259] 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].

[0260] The information corresponding to the weighting coefficient may be, for example, a potential, a resistance value, or a current amount. When the current amount is used as the information corresponding to the weighting coefficient, the input current may be generated using a current output type digital-to-analog converter (IDAC).

[0261] 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. 21 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.

[0262] The circuit XLD has a function of supplying second data, which is an input value, to the wirings WX1L[1] to WX1L[m].

[0263] The information corresponding to the input value may be, for example, a potential and a current amount. When the current amount 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.

[0264] 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.

[0265] The circuit XLD and the circuit WLD have a function of selecting a circuit MP to which information corresponding to first data input from the circuit ILD is to be written. 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.

[0266] 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 or a current amount) corresponding to the result of a product-sum operation input from the wiring OL[j] and the wiring OLB[j], andｊ （ｋ） The circuit AFP compares information (for example, potential or current amount) 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:

[0267] <<Circuit MP>> Next, the circuit MP will be described. An example circuit configuration applicable to the circuit MP[i, j] is shown in FIG. 22. 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.

[0268] 22, 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.

[0269] As an example, the transistors M1 to M3 shown in FIG. 22 are 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.

[0270] The arithmetic circuit 1350 described in this section 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. 22 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 applies not only to FIG. 22 but also to transistors described elsewhere in the specification or transistors illustrated in other drawings.

[0271] In this specification and the like, unless otherwise specified, the off-state current refers to the drain current when a transistor is in an off state (also referred to as a non-conducting state or a cut-off state). Unless otherwise specified, the off-state current refers to the drain current when a transistor is in an off state (also referred to as a non-conducting state or a cut-off state). ｇｓ is the threshold voltage V ｔｈ (For p-channel transistors, V ｔｈ This refers to a state of being (higher than)

[0272] 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 this specification or illustrated in other drawings, as well as the circuit diagram in FIG. 22 .

[0273] 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 used. As an example of a transistor, a transistor having single crystal silicon, or a transistor having a non-single crystal semiconductor film typified by amorphous silicon, polycrystalline silicon (including low-temperature polysilicon), microcrystalline (also called microcrystalline, nanocrystalline, or semi-amorphous) silicon, or the like can be used. Alternatively, a thin film transistor (TFT) made of a thin film of such a semiconductor can be used. The use of TFTs has various advantages. For example, since they can be manufactured at a lower temperature than single crystal silicon, manufacturing costs can be reduced or the manufacturing equipment can be made larger.

[0274] As an example of a transistor, a transistor including a compound semiconductor (for example, silicon germanium (SiGe), gallium arsenide (GaAs), or the like) or an oxide semiconductor (OS transistor) can be used. Alternatively, a thin film transistor obtained by thinning these compound semiconductors or these oxide semiconductors 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 wiring, resistors, pixel electrodes, light-transmitting electrodes, or the like. Since these can be deposited or formed simultaneously with the transistor, costs can be reduced.

[0275] Examples of the oxide semiconductor include oxides containing at least one of indium, an element M (examples of the element M include 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.

[0276] 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.

[0277] 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 resistant to impacts.

[0278] In the circuit MP of FIG. 22 , 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.

[0279] 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.

[0280] In the holding unit HC shown in FIG. 22, 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.

[0281] 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. 22 can hold the potential by inputting a predetermined amount of current from the wiring OL when the transistors M2 and M3 are turned on, writing a potential corresponding to the amount of current 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, current can be input from the wiring OL, and a potential corresponding to the magnitude of the current can be held in the capacitor C1. Therefore, when the first data is input, the influence of variations in the current characteristics (such as threshold voltage) of the transistor M1 can be reduced.

[0282] The current input to the wiring OL can be input and generated using a current output type digital-to-analog converter circuit.

[0283] 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.

[0284] 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.

[0285] In this way, an arithmetic circuit with high arithmetic accuracy or high reliability is provided.

[0286] <<Configuration Example 2 of Arithmetic Circuit>> Another example of an arithmetic circuit MAC1 that performs a product-sum operation will be described.

[0287] 23 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. 23 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).

[0288] 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.

[0289] 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].

[0290] The cell array CA includes cells IM[1,1] to IM[m,n] (where m is an integer equal to or greater than 1 and n is an integer equal to or greater than 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].

[0291] Note that the cell array CA in Figure 23 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.

[0292] 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.

[0293] In particular, it is preferable that the sizes (e.g., channel length, channel width, transistor configuration, etc.) of the transistor 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 transistor 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 transistor 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 transistor 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 transistor F1 and the transistor F1m are equal to each other, and it is also preferable that the sizes of the transistor F2 and the transistor F2m are equal to each other.

[0294] 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.

[0295] 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.

[0296] For example, the transistor F1 and / or the transistor F1m is preferably an OS transistor. 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.

[0297] 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, thereby 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.

[0298] 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 (including low-temperature polysilicon), and single-crystal silicon.

[0299] 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 with temperature, 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 a high-temperature environment. 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.

[0300] 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.

[0301] 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.

[0302] The arithmetic circuit described in this section 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. 23 are n-channel transistors, some or all of the transistors may be replaced with p-channel transistors.

[0303] 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.

[0304] The wiring VE is a wiring for passing current between the first terminal and the second terminal of each of the transistors F2 in 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 each of the transistors F2m in 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.

[0305] 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. 23 , 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].

[0306] 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. 23 , 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].

[0307] 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. 23 , 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].

[0308] 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. 23 , 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].

[0309] 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 C5m is electrically connected to the wiring XCL[1]. Note that in FIG. 23, the node NNref[1] 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 C5m in the cell IMref[1].

[0310] 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 C5m is electrically connected to the wiring XCL[m]. Note that in FIG. 23 , 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 C5m in the cell IMref[m].

[0311] 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.

[0312] 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.

[0313] 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.

[0314] 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.

[0315] 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.

[0316] 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.

[0317] 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.

[0318] 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.

[0319] The circuit WCS has a function of supplying data to be stored in each cell of the cell array CA.

[0320] 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.

[0321] 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].

[0322] 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.

[0323] 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].

[0324] 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 functional 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].

[0325] 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, or a threshold function.

[0326] A current output type digital-to-analog conversion circuit can be used as the circuit WCS shown in Fig. 23. Also, a current output type digital-to-analog conversion circuit can be used as the circuit XCS shown in Fig. 23.

[0327] 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.

[0328] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0329] In this embodiment, a display device that can be included in an electronic device according to one embodiment of the present invention will be described. Note that the display device described in this embodiment can be applied to the display unit DSP described in the above embodiment.

[0330] 24 is a cross-sectional view illustrating an example of a display device that can be included in an electronic device of one embodiment of the present invention. As an example, the display device 100 illustrated in FIG. 24 has a structure in which a pixel circuit and a driver circuit are provided over a substrate 310.

[0331] Specifically, the display device 100 includes, for example, a circuit layer SICL, a wiring layer LINL, and a pixel layer PXAL. The circuit layer SICL includes, for example, a substrate 310, and a transistor 300 is formed on the substrate 310. A wiring layer LINL is provided above the transistor 300, and wiring is provided in the wiring layer LINL to electrically connect the transistor 300, a transistor 200 (described later), a light-emitting device 150a, a light-emitting device 150b (described later), and the like. A pixel layer PXAL is provided above the wiring layer LINL, and the pixel layer PXAL includes, for example, the transistor 200, a light-emitting device 150 (the light-emitting device 150a and the light-emitting device 150b in FIG. 24 ), and the like.

[0332] The substrate 310 can be, for example, a semiconductor substrate (e.g., a single-crystal substrate) made of silicon or germanium. Other than a semiconductor substrate, the substrate 310 can also be, for example, a silicon-on-insulator (SOI) substrate, a glass substrate, a quartz substrate, a plastic substrate, a sapphire glass substrate, a metal substrate, a stainless steel substrate, a substrate having stainless steel foil, a tungsten substrate, a substrate having tungsten foil, a flexible substrate, a laminated film, paper containing a fibrous material, or a base film. Examples of glass substrates include barium borosilicate glass, aluminoborosilicate glass, and soda-lime glass. Examples of flexible substrates, laminated films, or base films include plastics such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), and polytetrafluoroethylene (PTFE). Another example of the flexible substrate, laminating film, or base film is a synthetic resin such as an acrylic resin. Another example of the flexible substrate, laminating film, or base film is polypropylene, polyester, polyvinyl fluoride, or polyvinyl chloride. Another example of the flexible substrate, laminating film, or base film is polyamide, polyimide, aramid, epoxy resin, inorganic vapor deposition film, or paper. Note that if the manufacturing process of the display device 100 includes a heat treatment, it is preferable to select a material with high heat resistance for the substrate 310.

[0333] In this embodiment, the substrate 310 is described as a semiconductor substrate made of silicon or the like.

[0334] The transistor 300 is provided over a substrate 310 and includes an element isolation layer 312, a conductor 316, an insulator 315, an insulator 317, a semiconductor region 313 formed of part of the substrate 310, and low-resistance regions 314a and 314b functioning as source and drain regions. Therefore, the transistor 300 is a Si transistor. Note that although FIG. 24 illustrates a structure in which one of the source and drain of the transistor 300 is electrically connected to the conductor 330, the conductor 356, and the conductor 366, which will be described later, via the conductor 328, the electrical connection structure of the semiconductor device of one embodiment of the present invention is not limited thereto. For example, the semiconductor device of one embodiment of the present invention may have a structure in which the gate of the transistor 300 is electrically connected to the conductor 330, the conductor 356, and the conductor 366 via the conductor 328.

[0335] The transistor 300 can be a Fin type transistor by, for example, covering the top surface and the side surfaces in the channel width direction of the semiconductor region 313 with a conductor 316 via an insulator 315 that functions as a gate insulating film. By configuring the transistor 300 as a Fin type transistor, the effective channel width can be increased, and the on-state characteristics of the transistor 300 can be improved. Furthermore, the contribution of the electric field of the gate electrode can be increased, and the off-state characteristics of the transistor 300 can be improved.

[0336] Note that the transistor 300 may be either a p-channel transistor or an n-channel transistor. Alternatively, a plurality of transistors 300 may be provided, and both p-channel and n-channel transistors may be used.

[0337] The region where the channel of the semiconductor region 313 is formed, the region nearby, the low-resistance region 314a serving as the source region or the drain region, and the low-resistance region 314b preferably contain a silicon-based semiconductor, and more preferably contain single-crystal silicon. Alternatively, each of the above-mentioned regions may be formed using a material containing germanium (Ge), silicon germanium (SiGe), gallium arsenide (GaAs), aluminum gallium arsenide (GaAlAs), or gallium nitride (GaN). Furthermore, each of the above-mentioned regions may be configured using silicon whose effective mass is controlled by applying stress to the crystal lattice and changing the lattice spacing. Alternatively, the transistor 300 may be, for example, a high electron mobility transistor (HEMT) using gallium arsenide and aluminum gallium arsenide.

[0338] The conductor 316 functioning as the gate electrode can be made of a conductive material such as a semiconductor material such as silicon containing an element that imparts n-type conductivity, such as arsenic or phosphorus, or an element that imparts p-type conductivity, such as boron, a metal material, an alloy material, or a metal oxide material.

[0339] Note that the work function is determined by the material of the conductor, and therefore the threshold voltage of the transistor can be adjusted by selecting the material of the conductor. Specifically, it is preferable to use one or both of titanium nitride and tantalum nitride as the conductor. Furthermore, in order to achieve both conductivity and embeddability, it is preferable to use one or both of tungsten and aluminum as the conductor in a stacked structure, and tungsten is particularly preferable in terms of heat resistance.

[0340] The element isolation layer 312 is provided to isolate a plurality of transistors formed on the substrate 310. The element isolation layer can be formed using, for example, a local oxidation of silicon (LOCOS) method, a shallow trench isolation (STI) method, or a mesa isolation method.

[0341] 24 is just an example, and the structure of the transistor 300 is not limited to this example, and an appropriate transistor may be used depending on the circuit configuration, driving method, etc. For example, the transistor 300 may have a planar structure instead of a fin structure.

[0342] In the transistor 300 shown in FIG. 24, an insulator 320, an insulator 322, an insulator 324, and an insulator 326 are stacked in this order from the substrate 310 side.

[0343] As insulators 320, 322, 324, and 326, for example, one or more selected from silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, aluminum oxide, aluminum oxynitride, aluminum nitride oxide, and aluminum nitride may be used.

[0344] The insulator 322 may function as a planarizing film that planarizes steps caused by the insulator 320 and the transistor 300 covered with the insulator 322. For example, the top surface of the insulator 322 may be planarized by planarization treatment using a chemical mechanical polishing (CMP) method or the like to improve the planarity.

[0345] Furthermore, the insulator 324 is preferably a barrier insulating film that prevents impurities such as water and hydrogen from diffusing from the substrate 310 or the transistor 300 to a region above the insulator 324 (for example, a region where the transistor 200, the light-emitting device 150a, the light-emitting device 150b, etc. are provided). Therefore, the insulator 324 is preferably an insulating material that has a function of suppressing the diffusion of impurities such as hydrogen atoms, hydrogen molecules, and water molecules (i.e., an insulating material through which the impurities are difficult to penetrate). Depending on the situation, the insulator 324 may be made of an insulating material that prevents the diffusion of nitrogen atoms, nitrogen molecules, and nitrogen oxide molecules (N ２ O, NO, NO ２ It is preferable to use an insulating material that has a function of suppressing the diffusion of impurities such as copper atoms and copper (i.e., the above-mentioned oxygen is less permeable). Alternatively, it is preferable to use an insulating material that has a function of suppressing the diffusion of oxygen (e.g., oxygen atoms and / or oxygen molecules).

[0346] As an example of a film having a barrier property against hydrogen, silicon nitride formed by a CVD method can be used.

[0347] The amount of desorption of hydrogen can be analyzed using, for example, thermal desorption spectroscopy (TDS). For example, in the TDS analysis, the amount of desorption of hydrogen from the insulator 324 is calculated as 10×10 per area of ​​the insulator 324 when the surface temperature of the film is in the range of 50° C. to 500° C. and the amount of desorption converted into hydrogen atoms is 10×10 １５ atoms / cm ２ Below 5 × 10, preferably １５ atoms / cm ２ The following is fine.

[0348] The insulator 326 preferably has a lower dielectric constant than the insulator 324. For example, the relative dielectric constant of the insulator 326 is preferably less than 4, and more preferably less than 3. Furthermore, for example, the relative dielectric constant of the insulator 326 is preferably 0.7 times or less, and more preferably 0.6 times or less, the relative dielectric constant of the insulator 324. By using a material with a low dielectric constant as the interlayer film, the parasitic capacitance that occurs between wirings can be reduced.

[0349] Furthermore, conductors 328, 330, etc., which connect to a light-emitting device or the like provided above the insulator 326, are embedded in the insulators 320, 322, 324, and 326. The conductors 328, 330, etc., function as plugs or wiring. Furthermore, for conductors that function as plugs or wiring, multiple structures may be collectively assigned the same reference numeral. Furthermore, in this specification, the wiring and the plug connecting to the wiring may be integrated. That is, there are cases where a portion of the conductor functions as wiring, and cases where a portion of the conductor functions as a plug.

[0350] The materials for each plug and wiring (conductor 328 and conductor 330) can be one or more conductive materials selected from metal materials, alloy materials, metal nitride materials, and metal oxide materials, and can be used in a single layer or a stacked layer. It is preferable to use a high-melting-point material such as tungsten or molybdenum, which has both heat resistance and conductivity, and tungsten is preferred. Alternatively, it is preferable to form the plug and wiring from a low-resistance conductive material such as aluminum or copper. Using a low-resistance conductive material can reduce the wiring resistance.

[0351] A wiring layer may be provided over the insulator 326 and the conductor 330. For example, in FIG. 24 , an insulator 350, an insulator 352, and an insulator 354 are stacked in this order over the insulator 326 and the conductor 330. A conductor 356 is formed in the insulator 350, the insulator 352, and the insulator 354. The conductor 356 functions as a plug or wiring connected to the transistor 300. Note that the conductor 356 can be formed using a material similar to that of the conductors 328 and 330.

[0352] Note that, for example, the insulator 350 is preferably an insulator that has barrier properties against hydrogen, oxygen, and water, similar to the insulator 324. Similarly to the insulator 326, the insulators 352 and 354 are preferably insulators with a relatively low dielectric constant in order to reduce parasitic capacitance between wirings. The insulators 362 and 364 function as an interlayer insulating film and a planarizing film. The conductor 356 preferably includes a conductor that has barrier properties against hydrogen, oxygen, and water.

[0353] Note that, for example, tantalum nitride is preferably used as the conductor having a barrier property against hydrogen. Furthermore, by stacking tantalum nitride and highly conductive tungsten, the diffusion of hydrogen from the transistor 300 can be suppressed while maintaining the conductivity of the wiring. In this case, a structure in which the tantalum nitride layer having a barrier property against hydrogen is in contact with the insulator 350 having a barrier property against hydrogen is preferable.

[0354] In addition, an insulator 360, an insulator 362, and an insulator 364 are stacked in this order on the insulator 354 and the conductor 356.

[0355] The insulator 360 is preferably an insulator having barrier properties against impurities such as water and hydrogen, similar to the insulator 324. Therefore, the insulator 360 can be made of, for example, a material that can be used for the insulator 324.

[0356] The insulators 362 and 364 function as an interlayer insulating film and a planarizing film. As the insulators 362 and 364, it is preferable to use an insulator that has a barrier property against impurities such as water and hydrogen, similar to the insulator 324. Therefore, a material that can be used for the insulator 324 can be used for one or both of the insulators 362 and 364.

[0357] Furthermore, openings are formed in the insulators 360, 362, and 364 in regions that overlap with part of the conductor 356, and the conductor 366 is provided to fill the openings. The conductor 366 is also formed over the insulator 362. For example, the conductor 366 functions as a plug or wiring connected to the transistor 300. Note that the conductor 366 can be formed using a material similar to that of the conductors 328 and 330.

[0358] An insulator 370 and an insulator 372 are stacked in this order on the insulator 364 and the conductor 366 .

[0359] The insulator 370 is preferably an insulator having barrier properties against impurities such as water and hydrogen, similar to the insulator 324. Therefore, the insulator 370 can be made of, for example, a material that can be used for the insulator 324.

[0360] The insulator 372 functions as an interlayer insulating film and a planarizing film. Similarly to the insulator 324, the insulator 372 is preferably an insulator having a barrier property against impurities such as water and hydrogen. Therefore, the insulator 372 can be made of a material that can be used for the insulator 324.

[0361] Furthermore, openings are formed in the insulators 370 and 372 in regions that overlap with a portion of the conductor 366, and the conductor 376 is provided to fill the openings. The conductor 376 is also formed on the insulator 372. After that, the conductor 376 is patterned into the shape of a wiring, a terminal, or a pad by etching or the like.

[0362] For example, copper, aluminum, tin, zinc, tungsten, silver, platinum, or gold can be used as the conductor 376. Note that the conductor 376 is preferably made of the same components as the material used for the conductor 216 included in the pixel layer PXAL, which will be described later.

[0363] Next, an insulator 380 is formed to cover the insulator 372 and the conductor 376, and then planarization treatment using a chemical mechanical polishing (CMP) method or the like is performed until the conductor 376 is exposed. In this way, the conductor 376 can be formed on the substrate 310 as a wiring, a terminal, or a pad.

[0364] As the insulator 380, it is preferable to use, for example, a film having barrier properties that prevent the diffusion of impurities such as water and hydrogen, similar to the insulator 324. That is, it is preferable to use, for the insulator 380, a material that can be used for the insulator 324. Alternatively, as the insulator 380, it is possible to use, for example, an insulator with a relatively low dielectric constant in order to reduce parasitic capacitance that occurs between wirings, similar to the insulator 326. That is, it is possible to use, for the insulator 380, a material that can be used for the insulator 326.

[0365] The pixel layer PXAL, for example, includes a substrate 210, a transistor 200, a light-emitting device 150 (light-emitting device 150a and light-emitting device 150b in FIG. 24), and a substrate 102. The pixel layer PXAL also includes, for example, an insulator 220, an insulator 222, an insulator 226, an insulator 250, an insulator 111, an insulator 112, an insulator 113, a layer 161 (layer 161a and layer 161b in FIG. 24), an insulator 162, and a resin layer 163. The pixel layer PXAL also includes, for example, a conductor 216, a conductor 228, a conductor 230, a conductor 121 (conductor 121a and conductor 121b in FIG. 24), a conductor 122, and a conductor 123.

[0366] 24, for example, the insulator 202 functions as a bonding layer together with the insulator 380. The insulator 202 is preferably made of the same material as that used for the insulator 380, for example.

[0367] A substrate 210 is provided above the insulator 202. In other words, the insulator 202 is formed on the lower surface of the substrate 210. As the substrate 210, for example, a substrate that can be applied to the substrate 310 is preferably used. Note that in the display device 100 of Fig. 24, the substrate 310 will be described as a semiconductor substrate made of silicon.

[0368] For example, a transistor 200 is formed on the substrate 210. The transistor 200 functions as a Si transistor because it is formed on the substrate 210, which is a semiconductor substrate made of silicon. Note that the description of the transistor 300 is to be referred to for the configuration of the transistor 200.

[0369] An insulator 220 and an insulator 222 are provided above the transistor 200. The insulator 220 functions as an interlayer insulating film and a planarizing film, similar to the insulator 320. The insulator 222 functions as an interlayer insulating film and a planarizing film, similar to the insulator 322.

[0370] A plurality of openings are provided in the insulator 220 and the insulator 222. The plurality of openings are formed in regions overlapping with the source and drain of the transistor 200 and a region overlapping with the conductor 376. Of the plurality of openings, a conductor 228 is formed in the opening formed in the region overlapping with the source and drain of the transistor 200. Of the remaining openings, an insulator 214 is formed on side surfaces of the opening formed in the region overlapping with the conductor 376, and a conductor 216 is formed in the remaining openings. In particular, the conductor 216 may be called a TSV (Through Silicon Via).

[0371] The conductor 216 or the conductor 228 can be made of, for example, a material that can be used for the conductor 328. In particular, it is preferable that the conductor 216 is made of the same material as the conductor 376.

[0372] The insulator 214 has a function of, for example, electrically insulating the substrate 210 from the conductor 216. Note that as the insulator 214, it is preferable to use a material that can be used for the insulators 320 and 324, for example.

[0373] The insulator 380 and the conductor 376 formed on the substrate 310 and the insulator 202 and the conductor 216 formed on the substrate 210 are joined together by, for example, a bonding process.

[0374] As a pre-process before the bonding process, for example, planarization is performed on the substrate 310 side to make the heights of the surfaces of the insulator 380 and the conductor 376 uniform. Similarly, planarization is performed on the substrate 210 side to make the heights of the insulator 202 and the conductor 216 uniform.

[0375] In the bonding process, when bonding the insulator 380 and the insulator 202, that is, bonding the insulating layers together, a hydrophilic bonding method can be used in which high flatness is achieved by polishing or the like, then surfaces that have been hydrophilically treated with oxygen plasma or the like are brought into contact with each other to temporarily bond them, and then the final bonding is performed by dehydrating them through heat treatment.The hydrophilic bonding method also produces bonds at the atomic level, so it is possible to obtain mechanically excellent bonds.

[0376] Furthermore, when bonding conductor 376 and conductor 216, i.e., bonding conductors together, a surface activated bonding method can be used, in which oxide films and impurity adsorption layers on the surfaces are removed by sputtering or other methods, and cleaned and activated surfaces are brought into contact and bonded together. Alternatively, a diffusion bonding method can be used, in which surfaces are bonded together using a combination of temperature and pressure. Both methods involve bonding at the atomic level, resulting in excellent bonding not only electrically but also mechanically.

[0377] By carrying out the above-described bonding process, the conductor 376 on the substrate 310 side can be electrically connected to the conductor 216 on the substrate 210 side. Furthermore, a connection having sufficient mechanical strength can be obtained between the insulator 380 on the substrate 310 side and the insulator 202 on the substrate 210 side.

[0378] When bonding the substrates 310 and 210, since the bonding surfaces of each substrate contain a mixture of insulating and metal layers, a surface activated bonding method and a hydrophilic bonding method may be combined. For example, a bonding method may be used in which the surfaces are polished and then cleaned, and the surface of the metal layer is subjected to an anti-oxidation treatment, followed by a hydrophilic treatment. Alternatively, the surface of the metal layer may be made of a resistant metal such as gold and then subjected to a hydrophilic treatment.

[0379] Note that bonding methods other than those described above may be used to bond the substrate 310 and the substrate 210. For example, flip-chip bonding may be used to bond the substrate 310 and the substrate 210. Furthermore, when using flip-chip bonding, connection terminals such as bumps may be provided above the conductor 376 on the substrate 310 side or below the conductor 216 on the substrate 210 side. Examples of flip-chip bonding include a method of injecting a resin containing anisotropic conductive particles between the insulator 380 and the insulator 202 and between the conductor 376 and the conductor 216 to bond them, and a method of bonding them using silver-tin solder. Alternatively, if the bumps and the conductors connected to the bumps are both made of gold, ultrasonic bonding may be used. Furthermore, in addition to the flip-chip bonding method described above, an underfill agent may be injected between the insulator 380 and the insulator 202 and between the conductor 376 and the conductor 216 to reduce physical stress such as impact and thermal stress. Furthermore, for example, a die bonding film may be used to bond the substrate 310 and the substrate 210 together.

[0380] An insulator 224 and an insulator 226 are stacked in this order on the insulator 222, the insulator 214, the conductor 216, and the conductor 228.

[0381] Like the insulator 324, the insulator 224 is preferably a barrier insulating film that prevents impurities such as water and hydrogen from diffusing into a region above the insulator 224. Therefore, it is preferable to use, for example, a material that can be used for the insulator 324 as the insulator 224.

[0382] The insulator 226 is preferably an interlayer film with a low dielectric constant, similar to the insulator 326. Therefore, the insulator 226 is preferably made of a material that can be used for the insulator 326, for example.

[0383] Furthermore, a conductor 230 electrically connected to the transistor 200, the light-emitting device 150, and the like is embedded in the insulator 224 and the insulator 226. The conductor 230 functions as a plug or wiring. For example, a material that can be used for the conductor 328, the conductor 330, and the like can be used as the conductor 230.

[0384] An insulator 250 and an insulator 111 are stacked in this order on the insulator 224 and the insulator 226 .

[0385] The insulator 250 is preferably an insulator having barrier properties against impurities such as water or hydrogen, similar to the insulator 324. Therefore, the insulator 250 can be made of, for example, a material that can be used for the insulator 324.

[0386] The insulator 111 is preferably an insulator that has a function of suppressing the diffusion of water, hydrogen, and oxygen, such as aluminum oxide, magnesium oxide, hafnium oxide, gallium oxide, indium gallium zinc oxide, silicon nitride, or silicon nitride oxide. For example, the insulator 111 is preferably made of silicon nitride, which has a higher hydrogen barrier property. Furthermore, the insulator 111 is preferably made of aluminum oxide or magnesium oxide, which has a high function of capturing and fixing hydrogen.

[0387] A highly flat film is preferably used as the insulator 111. In this case, the insulator 111 can be formed using an organic material such as an acrylic resin or polyimide.

[0388] Furthermore, openings are formed in the regions of the insulator 250 and the insulator 111 that overlap with a portion of the conductor 230, and the conductor 121 is provided to cover the region where the insulator 111 is formed. Note that in this specification and the like, the conductors 121a and 121b shown in FIG. 24 are collectively referred to as the conductor 121. For example, the conductor 230 functions as a plug or wiring that connects to the light-emitting device 150. Note that the conductor 121 can be provided using the same material as the conductors 328 and 330.

[0389] In addition, in the region where the conductor 121a is formed, a layer 161a is preferably buried in the recess of the opening. A conductor 122a is preferably formed over the conductor 121a and the layer 161a. In addition, in the region where the conductor 121b is formed, a layer 161b is preferably buried in the recess of the opening. A conductor 122b is preferably formed over the conductor 121b and the layer 161b. Note that in this specification and the like, the layers 161a and 161b shown in FIG. 24 are collectively referred to as layer 161. The conductors 122a and 122b shown in FIG. 24 are collectively referred to as conductor 122.

[0390] At least one of the conductor 121 and the conductor 122 may be called a pixel electrode.

[0391] The layer 161 has a function of planarizing the recesses of the conductor 121. By providing the layer 161, unevenness of the surface on which the EL layer is formed can be reduced, and coverage can be improved. Furthermore, by providing the conductor 122 over the conductor 121 and the layer 161, a region overlapping with the recesses of the conductor 121 can also be used as a light-emitting region in some cases. This can increase the aperture ratio of the pixel.

[0392] The layer 161 may be an insulating layer or a conductive layer. For example, the layer 161 may be made of a material selected from various inorganic insulating materials, organic insulating materials, and conductive materials. In particular, the layer 161 is preferably made of an insulating material.

[0393] An insulating layer containing an organic material can be suitably used as the layer 161. For example, acrylic resin, polyimide resin, epoxy resin, polyamide resin, polyimideamide resin, siloxane resin, benzocyclobutene resin, phenol resin, or precursors of these resins can be used as the layer 161. Alternatively, a photosensitive resin can be used as the layer 161. The photosensitive resin can be a positive material or a negative material.

[0394] By using a photosensitive resin, the layer 161 can be manufactured only through exposure and development steps, and it is possible to reduce the influence of dry etching or wet etching on the surface of the conductor 121. Furthermore, by forming the layer 161 using a negative photosensitive resin, it may be possible to form the layer 161 using the same photomask (exposure mask) as that used to form the opening in the insulator 111.

[0395] The conductor 122 is provided on the conductor 121 and the layer 161. The conductor 122 has a first region in contact with the upper surface of the conductor 121 and a second region in contact with the upper surface of the layer 161. It is preferable that the height of the upper surface of the conductor 121 in contact with the first region and the height of the upper surface of the layer 161 in contact with the second region are the same or approximately the same.

[0396] The pixel electrode described in this embodiment mode includes, for example, a material that reflects visible light, and the counter electrode includes a material that transmits visible light.

[0397] The display device 100 is a top-emission type. Light emitted from the light-emitting device is emitted toward the substrate 102. The substrate 102 is preferably made of a material that is highly transparent to visible light.

[0398] A light-emitting device 150a is provided above the conductor 121a, and a light-emitting device 150b is provided above the conductor 121b.

[0399] Here, the light emitting device 150a and the light emitting device 150b will be described.

[0400] The light-emitting device described in this embodiment refers to a self-luminous light-emitting device such as an organic EL element (also called an OLED (organic light-emitting diode)). Note that the light-emitting device electrically connected to the pixel circuit can be a self-luminous light-emitting device such as an LED (light-emitting diode), a micro LED, a QLED (quantum-dot light-emitting diode), or a semiconductor laser.

[0401] The conductor 122a and the conductor 122b can be formed, for example, by forming a conductive film over the conductor 121a, the conductor 121b, the layer 161a, and the layer 161b, and then applying photolithography or electron beam lithography to the conductive film.

[0402] The conductor 122a and the conductor 122b function as the anodes of the light-emitting device 150a and the light-emitting device 150b included in the display device 100, respectively, as an example.

[0403] For example, indium tin oxide (sometimes referred to as ITO) can be used as the conductor 122a and the conductor 122b.

[0404] Furthermore, each of the conductors 122a and 122b may have a stacked structure of two or more layers instead of a single layer. For example, a conductor with high visible light reflectivity can be used as the first layer conductor, and a conductor with high light transmissivity can be used as the top layer conductor. Examples of conductors with high visible light reflectivity include silver, aluminum, or an alloy film of silver (Ag), palladium (Pd), and copper (Cu) (Ag-Pd-Cu (APC) film). Examples of conductors with high light transmissivity include the aforementioned indium tin oxide. Furthermore, the conductors 122a and 122b may be, for example, a stacked film of aluminum sandwiched between a pair of titanium films (a stacked film of Ti, Al, and Ti in this order), or a stacked film of silver sandwiched between a pair of indium tin oxide films (a stacked film of ITO, Ag, and ITO in this order).

[0405] An EL layer 141a is provided over the conductor 122a, and an EL layer 141b is provided over the conductor 122b.

[0406] It is preferable that the EL layer 141a and the EL layer 141b each have a light-emitting layer that emits light of a different color. For example, the EL layer 141a may have a light-emitting layer that emits light of one of red (R), green (G), and blue (B), and the EL layer 141b may have a light-emitting layer that emits light of one of the remaining two. Although not shown in FIG. 24 , if an EL layer other than the EL layer 141a and the EL layer 141b is provided, the EL layer may have a light-emitting layer that emits light of the remaining one. In this way, the display device 100 may have a structure (SBS structure) in which different light-emitting layers for each color are formed on multiple pixel electrodes (the conductors 121a and 121b in FIG. 24 ).

[0407] The combination of colors emitted by the light-emitting layers included in the EL layer 141 a and the EL layer 141 b is not limited to the above, and may also be colors such as cyan, magenta, yellow, etc. Although the above example shows three colors, the number of colors emitted by the light-emitting device 150 included in the display device 100 may be two, three, or four or more.

[0408] The EL layer 141a and the EL layer 141b may each include one or more of an electron injection layer, an electron transport layer, a hole injection layer, and a hole transport layer in addition to a layer containing a light-emitting organic compound (light-emitting layer).

[0409] In addition, the EL layer 141a and the EL layer 141b can be formed by a method such as a vapor deposition method (vacuum vapor deposition method, etc.), a coating method (for example, a dip coating method, a die coating method, a bar coating method, a spin coating method, and a spray coating method), a printing method (for example, an inkjet method, a screen (stencil printing) method, an offset (lithographic printing) method, a flexographic (relief printing) method, a gravure method, and a microcontact method).

[0410] When the coating method and the printing method are used as the film formation method, the material to be formed into the film can be, for example, a polymer compound (e.g., oligomer, dendrimer, and polymer), a medium molecular compound (a compound in the intermediate range between a low molecular weight and a high molecular weight: molecular weight 400 to 4000), or an inorganic compound (e.g., quantum dot material). The quantum dot material can be a colloidal quantum dot material, an alloy quantum dot material, a core-shell quantum dot material, or a core quantum dot material.

[0411] For example, light emitting device 150a and light emitting device 150b in FIG. 24 can be configured with a plurality of layers such as light emitting layer 4411 and layer 4430, as in light emitting device 150 shown in FIG. 25A.

[0412] 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).

[0413] A structure having a layer 4420, a light-emitting layer 4411, and a layer 4430 provided between a pair of electrodes (conductor 121 and conductor 122 described later) can function as a single light-emitting unit, and in this specification, the structure of Figure 25A is called a single structure.

[0414] 25B shows a modified example of the EL layer 141 included in the light-emitting device 150 shown in Fig. 25A. Specifically, the light-emitting device 150 shown in Fig. 25B includes a layer 4430-1 on the conductor 121, 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 a conductor 122 on the layer 4420-2. For example, when the conductor 121 is the anode and the conductor 122 is the 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 conductor 121 is a cathode and the conductor 122 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. Such a layer structure makes it possible to efficiently inject carriers into the light-emitting layer 4411 and increase the efficiency of carrier recombination in the light-emitting layer 4411.

[0415] Note that a structure in which a plurality of light-emitting layers (light-emitting layers 4411, 4412, and 4413) are provided between the layer 4420 and the layer 4430 as shown in FIG. 25C is also a variation of the single structure.

[0416] A laminate having multiple layers, such as layer 4420, light-emitting layer 4411, and layer 4430, may be referred to as a light-emitting unit. Multiple light-emitting units may be connected in series via an intermediate layer (charge generation layer). Specifically, as shown in FIG. 25D , multiple light-emitting units, such as light-emitting unit 4400a and light-emitting unit 4400b, may be connected in series via an intermediate layer (charge generation layer) 4440. In this specification, such a structure is referred to as a tandem structure. In this specification, the tandem structure may also be referred to as a stack structure. By forming a light-emitting device into a tandem structure, a light-emitting device capable of emitting light with high brightness may be obtained. By forming a light-emitting device into a tandem structure, improvements in the light-emitting efficiency and lifespan of the light-emitting device may be expected. When the light-emitting device 150 of the display device 100 of Figure 24 has a tandem structure, the EL layer 141 can be configured to include, for example, layer 4420, light-emitting layer 4411, and layer 4430 of light-emitting unit 4400a, intermediate layer 4440, and layer 4420, light-emitting layer 4412, and layer 4430 of light-emitting unit 4400b.

[0417] Furthermore, when displaying white, the SBS structure described above can reduce power consumption compared to the single and tandem structures described above. Therefore, when it is desired to keep power consumption low, the SBS structure is preferable. On the other hand, the single and tandem structures are preferable because their manufacturing processes are easier than those of the SBS structure, allowing for lower manufacturing costs or higher manufacturing yields.

[0418] The light-emitting device 150 can emit light in red, green, blue, cyan, magenta, yellow, or white, depending on the material of the EL layer 141. Furthermore, the color purity can be further improved by providing the light-emitting device 150 with a microcavity structure.

[0419] A light-emitting device that emits white light preferably has a configuration in which two or more types of luminescent materials are contained in the luminescent layer. To obtain white light emission, for example, luminescent materials may be selected such that the respective emissions of the two luminescent materials are in a complementary color relationship. Alternatively, to obtain white light emission, for example, luminescent materials may be selected such that the emission color of one selected from three or more luminescent materials is in a complementary color relationship with the emission color obtained by combining the emissions of the remaining luminescent materials.

[0420] The light-emitting layer preferably contains two or more light-emitting materials that emit light of R (red), G (green), B (blue), Y (yellow), and O (orange). Alternatively, the light-emitting layer preferably contains two or more light-emitting materials, and the light emitted by each of the light-emitting materials preferably contains spectral components of two or more colors of R, G, and B.

[0421] 24 , a gap is provided between two EL layers between adjacent light-emitting devices. Specifically, in FIG. 24 , a recess is formed between adjacent light-emitting devices, and the insulator 112 covers the side surfaces (side surfaces of the conductor 121a, the conductor 122a, and the EL layer 141a, and side surfaces of the conductor 121b, the conductor 122b, and the EL layer 141b) and the bottom surface (a partial region of the insulator 111) of the recess. Furthermore, the insulator 162 is formed on the insulator 112 so as to fill the recess. In this manner, the EL layer 141a and the EL layer 141b are preferably provided so as not to be in contact with each other. This can suitably prevent unintended light emission (also known as crosstalk) caused by current (also referred to as lateral leakage current) flowing through the two adjacent EL layers. Therefore, contrast can be improved, and a display device with high display quality can be realized. Furthermore, for example, by configuring the display device so that the lateral leakage current between the light-emitting devices is extremely low, the black display performed by the display device can be a display with extremely little light leakage (also called true black display).

[0422] The EL layers 141a and 141b can be formed by a method using photolithography. For example, an EL film to be the EL layers 141a and 141b is formed on the conductor 122, and then the EL film is patterned by photolithography to form the EL layers 141a and 141b. This also makes it possible to provide a gap between the two EL layers between adjacent light-emitting devices.

[0423] The insulator 112 can be an insulating layer containing an inorganic material. For example, an inorganic insulating film such as an insulating oxide film, a nitride insulating film, an oxynitride insulating film, or a nitride oxide insulating film can be used for the insulator 112. The insulator 112 may have a single-layer structure or a stacked-layer structure. Examples of oxide insulating films include a silicon oxide film, an aluminum oxide film, a magnesium oxide film, an indium gallium zinc oxide film, a gallium oxide film, a germanium oxide film, an yttrium oxide film, a zirconium oxide film, a lanthanum oxide film, a neodymium oxide film, a hafnium oxide film, and a tantalum oxide film. Examples of nitride insulating films include a silicon nitride film and an aluminum nitride film. Examples of oxynitride insulating films include a silicon oxynitride film and an aluminum oxynitride film. Examples of nitride oxide insulating films include a silicon nitride oxide film and an aluminum nitride oxide film. In particular, an aluminum oxide film is preferable because it has a high selectivity with respect to the EL layer in an etching process and has a function of protecting the EL layer in the formation of the insulator 162 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 an ALD method as the insulator 112, the insulator 112 can have few pinholes and has excellent functionality for protecting the EL layer.

[0424] 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.

[0425] The insulator 112 can be formed by a sputtering method, a CVD method, a PLD method, or an ALD method. The insulator 112 is preferably formed by an ALD method because it has good coverage.

[0426] The insulator 162 provided on the insulator 112 has the function of planarizing recesses formed in the insulator 112 between adjacent light-emitting devices. In other words, the insulator 162 has the effect of improving the flatness of the surface on which the conductor 123 (described later) is formed. An insulating layer containing an organic material can be suitably used for the insulator 162. For example, the insulator 162 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 insulator 162 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 insulator 162 can also be made of, for example, a photosensitive resin. The photosensitive resin can be, for example, a photoresist. The photosensitive resin may be, for example, a positive-type material or a negative-type material.

[0427] The difference in height between the top surface of the insulator 162 and the top surface of the EL layer 141a or 141b is, for example, preferably 0.5 times or less, more preferably 0.3 times or less, the thickness of the insulator 162. For example, the insulator 162 may be provided so that the top surface of the EL layer 141a or 141b is higher than the top surface of the insulator 162. For example, the insulator 162 may be provided so that the top surface of the insulator 162 is higher than the top surface of the light-emitting layer of the EL layer 141a or 141b.

[0428] A conductor 123 is provided over the EL layer 141a, the EL layer 141b, the insulator 112, and the insulator 162. An insulator 113 is provided over each of the light-emitting devices 150a and 150b.

[0429] The conductor 123 functions as, for example, a common electrode for the light-emitting device 150 a and the light-emitting device 150 b. In order to emit light from the light-emitting device 150 upward from the display device 100, the conductor 122 preferably includes a light-transmitting conductive material.

[0430] The conductor 123 is preferably a highly conductive material that is light-transmitting and light-reflective (sometimes called a semi-transparent / semi-reflective electrode). The conductor 122 can be made of, for example, an alloy of silver and magnesium or indium tin oxide.

[0431] The insulator 113 is sometimes referred to as a protective layer, and providing the insulator 113 above each of the light-emitting devices 150a and 150b can improve the reliability of the light-emitting devices. In other words, the insulator 113 functions as a passivation film that protects the light-emitting devices 150a and 150b. Therefore, the insulator 113 is preferably made of a material that prevents the intrusion of water and the like. For example, the insulator 113 can be made of a material that can be used for the insulator 111. Specifically, for example, aluminum oxide, silicon nitride, or silicon nitride oxide can be used for the insulator 113.

[0432] A resin layer 163 is provided on the insulator 113. Furthermore, a substrate 102 is provided on the resin layer 163.

[0433] For example, a light-transmitting substrate is preferably used as the substrate 102. By using a light-transmitting substrate for the substrate 102, light emitted from the light-emitting devices 150a and 150b can be emitted upward from the substrate 102.

[0434] Note that the display device of one embodiment of the present invention is not limited to the configuration of the display device 100 illustrated in Fig. 24. The configuration of the display device of one embodiment of the present invention may be changed as appropriate within the scope of solving the problem.

[0435] For example, the transistor 200 included in the pixel layer PXAL of the display device 100 in Fig. 24 may be a transistor having a metal oxide in a channel formation region (hereinafter referred to as an OS transistor). The display device 100 in Fig. 26 has a configuration in which a transistor 500 (OS transistor) instead of the transistor 200 and a light-emitting device 150 are provided above the circuit layer SICL and the wiring layer LINL of the display device 100 in Fig. 24.

[0436] 26 , the transistor 500 is provided over an insulator 512. The insulator 512 is provided above the insulator 364 and the conductor 366, and a substance having a barrier property against oxygen and hydrogen is preferably used for the insulator 512. Specifically, for example, silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, aluminum oxide, aluminum oxynitride, aluminum nitride oxide, or aluminum nitride can be used for the insulator 512.

[0437] As an example of a film having a barrier property against hydrogen, silicon nitride formed by a CVD method can be used. Here, diffusion of hydrogen into a semiconductor element including an oxide semiconductor, such as the transistor 500, may degrade the characteristics of the semiconductor element. Therefore, it is preferable to use a film that suppresses hydrogen diffusion between the transistor 500 and the transistor 300. Specifically, the film that suppresses hydrogen diffusion is a film that releases a small amount of hydrogen.

[0438] For example, the insulator 512 can be made of a material similar to that of the insulator 320. By using a material with a relatively low dielectric constant for these insulators, parasitic capacitance between wirings can be reduced. For example, the insulator 512 can be made of a silicon oxide film or a silicon oxynitride film.

[0439] An insulator 514 is provided over the insulator 512, and the transistor 500 is provided over the insulator 514. An insulator 576 is formed over the insulator 512 to cover the transistor 500. An insulator 581 is provided above the insulator 576 to cover the insulator 576.

[0440] The insulator 514 is preferably a film having a barrier property that prevents impurities such as water and hydrogen from diffusing from the substrate 310 or a region where circuit elements are provided below the insulator 512 to the region where the transistor 500 is provided. Therefore, the insulator 514 can be made of silicon nitride formed by a CVD method, for example.

[0441] The transistor 500 includes a first gate and a second gate, and a metal oxide in a channel formation region, the metal oxide being located between the first gate and the second gate.

[0442] The transistor 500 also has a first gate insulating film over the first gate. The first gate insulating film can have a single film or a stacked structure of multiple films. A metal oxide is located over the first gate insulating film.

[0443] As described above, the transistor 500 illustrated in FIG. 26 is an OS transistor including a metal oxide in a channel formation region. As the metal oxide, for example, an In-M-Zn oxide containing indium, an element M, and zinc (the element M is one or more elements selected from aluminum, gallium, yttrium, tin, copper, vanadium, beryllium, boron, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, and magnesium) can be used. Specifically, for example, an oxide containing indium, gallium, and zinc (sometimes referred to as IGZO) can be used as the metal oxide. For example, an oxide containing indium, aluminum, and zinc (sometimes referred to as IAZO) can be used as the metal oxide. For example, an oxide containing indium, aluminum, gallium, and zinc (sometimes referred to as IAGZO) can be used as the metal oxide. In addition to the above, the metal oxide may be In-Ga oxide, In-Zn oxide, or indium oxide.

[0444] In particular, it is preferable to use a metal oxide functioning as a semiconductor having a band gap of 2 eV or more, preferably 2.5 eV or more. By using such a metal oxide having a wide band gap, the off-state current (sometimes referred to as leakage current) of a transistor can be reduced.

[0445] In particular, it is preferable to use a transistor, such as an OS transistor, whose off-state current is sufficiently small even when the source-drain voltage is large as the driving transistor included in the pixel circuit. By using an OS transistor as the driving transistor, the amount of off-state current flowing in the light-emitting device can be reduced when the driving transistor is in an off state, thereby sufficiently reducing the luminance of light emitted from the light-emitting device through which the off-state current flows. Therefore, when a driving transistor with a large off-state current is compared with a driving transistor with a small off-state current, when black is displayed in the pixel circuit, the light emission luminance of the pixel circuit including the driving transistor with a small off-state current can be lower than that of the pixel circuit including the driving transistor with a large off-state current. In other words, by using an OS transistor, it is possible to suppress floating black when black is displayed in the pixel circuit.

[0446] The off-state current of an OS transistor per 1 μm of channel width at room temperature is 1 aA (1×10 −１８ A) Below, 1zA (1×10 −２１ A) or less, or 1 yA (1 x 10 −２４ Note that the amount of off-state current of a Si transistor per 1 μm of channel width at room temperature can be 1 fA (1×10 −１５ A) More than 1pA (1×10 −１２ Therefore, it can be said that the off-state current of an OS transistor is about 10 orders of magnitude lower than that of a Si transistor.

[0447] Furthermore, in order to increase the light emission luminance of a light-emitting device included in a pixel circuit, it is necessary to increase the amount of current flowing through the light-emitting device. To achieve this, it is necessary to increase the source-drain voltage of a driving transistor included in the pixel circuit. Since an OS transistor has a higher source-drain withstand voltage than a Si transistor, a high voltage can be applied between the source and drain of the OS transistor. Therefore, by using an OS transistor as the driving transistor included in a pixel circuit, a high voltage can be applied between the source and drain of the OS transistor, thereby increasing the amount of current flowing through the light-emitting device and increasing the light emission luminance of the light-emitting device.

[0448] Furthermore, when the transistor operates in the saturation region, the OS transistor can reduce the change in source-drain current with respect to a change in gate-source voltage compared to a Si transistor. Therefore, by using an OS transistor as a driving transistor included in a pixel circuit, the current flowing between the source and drain can be precisely determined by changing the gate-source voltage, and the amount of current flowing through the light-emitting device can be precisely controlled. Therefore, the light emission luminance of the light-emitting device can be precisely controlled (the gradation in the pixel circuit can be increased).

[0449] Furthermore, in terms of the saturation characteristics of the current that flows when a transistor operates in a saturation region, an OS transistor can flow a constant current (saturation current) that is more stable than a Si transistor, even when the source-drain voltage gradually increases. Therefore, by using an OS transistor as a driving transistor, a stable constant current can be flowed through a light-emitting device, for example, even when the current-voltage characteristics of a light-emitting device containing an EL material vary. In other words, when an OS transistor operates in a saturation region, the source-drain current hardly changes even when the source-drain voltage increases, and thus the light-emitting luminance of the light-emitting device can be stabilized.

[0450] As described above, by using an OS transistor as a driving transistor included in a pixel circuit, it is possible to achieve "suppression of black floating," "increase in light emission luminance," "multiple gray levels," "suppression of variations in light-emitting devices," and the like. Therefore, a display device including the pixel circuit can display a clear and smooth image, and as a result, one or more of image clarity (image sharpness) and a high contrast ratio can be observed. Note that image clarity (image sharpness) may refer to either or both of suppression of motion blur and suppression of black floating. Furthermore, by configuring the driving transistor included in the pixel circuit to have an extremely low off-state current, black display performed by the display device can be achieved with extremely little light leakage (true black display).

[0451] The transistor 500 also has a pair of conductors on the metal oxide. One of the pair of conductors functions as one of the source and drain electrodes of the transistor 500, and the other of the pair of conductors functions as the other of the source and drain electrodes of the transistor 500.

[0452] The pair of conductors, the metal oxide, and the first gate insulating film are covered with an insulator 573. The insulator 573 functions as a barrier film that prevents diffusion of impurities such as water and hydrogen into the metal oxide. An insulator 574 that functions as an interlayer film is provided over the insulator 573.

[0453] An opening reaching the first gate insulating film is provided in a region of the insulator 574 overlapping the first gate. By forming the opening, a pair of conductors are also formed in a self-aligned manner. A second gate insulating film is formed on the bottom and side surfaces of the opening. A second gate is formed on the second gate insulator to fill the opening. An insulator 575 is formed in contact with the insulator 574, the second gate insulator, and the second gate. The insulator 576 is formed by the insulators 514 and 576 to surround the insulator 575 and the transistor 500. An insulator 581 is formed on the insulator 576.

[0454] The insulator 574 can be, for example, silicon oxide, silicon oxynitride, silicon oxide doped with fluorine, silicon oxide doped with carbon, silicon oxide doped with carbon and nitrogen, or silicon oxide having vacancies.

[0455] It is preferable that one or more selected from the insulators 573, 575, 576, and 581 function as a barrier insulating film that suppresses diffusion of impurities such as water and hydrogen from above the transistor 500 to the transistor 500. Therefore, one or more selected from the insulators 573, 575, 576, and 581 suppress diffusion of impurities such as hydrogen atoms, hydrogen molecules, water molecules, nitrogen atoms, nitrogen molecules, and nitrogen oxide molecules (N ２ O, NO, NO ２ It is preferable to use an insulating material that has a function of suppressing the diffusion of impurities such as copper atoms (e.g., copper atoms) or copper atoms (i.e., the impurities are less likely to permeate through the insulating material), or it is preferable to use an insulating material that has a function of suppressing the diffusion of oxygen (e.g., oxygen atoms and / or oxygen molecules) (i.e., the oxygen is less likely to permeate through the insulating material).

[0456] It is preferable to use an insulator having a function of suppressing diffusion of oxygen and impurities such as water and hydrogen as one or more of the insulators 573, 575, 576, and 581. For example, it is preferable to use aluminum oxide, magnesium oxide, hafnium oxide, gallium oxide, indium-gallium-zinc oxide, silicon nitride, or silicon nitride oxide as one or more of the insulators 573, 575, 576, and 581.

[0457] Openings for forming plugs or wirings are provided in the insulators 581, 576, 575, 574, and 573, and one of the source and drain electrodes of the transistor 500. In addition, a conductor 540 functioning as a plug or wiring is formed in the openings.

[0458] For example, the insulator 581 is preferably an insulator that functions as an interlayer film and a planarizing film.

[0459] An insulator 224 and an insulator 226 are formed in this order above the insulator 581 and the conductor 540. Note that for descriptions of the insulators, conductors, and circuit elements located above the insulator 224, including the insulator 224, please refer to the description of the display device 100 in FIG.

[0460] 24 shows a display device formed by bonding a semiconductor substrate on which a light-emitting device 150, a pixel circuit, and the like are formed and a semiconductor substrate on which a driver circuit and the like are formed, and FIG. 26 shows a display device in which the light-emitting device 150, the pixel circuit, and the like are formed on a semiconductor substrate on which a driver circuit is formed, but the display device according to the electronic device of one embodiment of the present invention is not limited to FIG. 24 or 26. The display device according to the electronic device of one embodiment of the present invention may be, for example, a display device having a structure in which only one layer of transistors is formed, instead of a layer structure in which two or more transistors are stacked.

[0461] Specifically, for example, a display device related to the electronic device of one embodiment of the present invention may have a structure including a circuit including a transistor 200 formed over a substrate 210 and a light-emitting device 150 provided above the transistor 200, as in the display device 100 illustrated in Figure 27A. Alternatively, for example, a display device 100 may have a structure in which an insulator 512 is formed over a substrate 501, and the transistor 500 is provided over the insulator 512 and the light-emitting device 150 is provided above the transistor 500, as in the display device 100 illustrated in Figure 27B. Note that as the substrate 501, for example, a substrate applicable to the substrate 310 can be used, and in particular, a glass substrate is preferably used.

[0462] 27A and 27B , the display device according to the electronic device of one embodiment of the present invention may have a structure in which only one layer of transistors is formed and a light-emitting device 150 is provided above the transistor. Although not shown, the display device according to the electronic device of one embodiment of the present invention may have a layer structure in which three or more layers of transistors are formed.

[0463] <Example of Sealing Structure of Display Device> Next, a sealing structure of the light-emitting device 150 that can be applied to the display device 100 of FIG. 24 will be described.

[0464] Fig. 28A is a cross-sectional view showing an example of a sealing structure that can be applied to the display device 100 of Fig. 24. Specifically, Fig. 28A illustrates an edge of the display device 100 of Fig. 24 and materials provided around the edge. Fig. 28A also illustrates an extracted portion of the pixel layer PXAL of the display device 100. Specifically, each of Fig. 28A illustrates an insulator 250, and an insulator, a conductor, and a light-emitting device 150a located above the insulator 250.

[0465] 28A , for example, an opening is provided. The conductor 123 is electrically connected to wiring provided below the insulator 250 through the opening. This allows a potential (e.g., an anode potential and a cathode potential in the light-emitting device 150a, etc.) to be supplied to the conductor 123, which functions as a common electrode. Note that one or both of the conductors included in the region 123CM and the conductors around the region 123CM may be referred to as a connection electrode.

[0466] 28A , an adhesive layer 164 is provided on or around an end of a resin layer 163. Specifically, the display device 100 is configured so that the insulator 113 and the substrate 102 are bonded to each other via the adhesive layer 164.

[0467] The adhesive layer 164 is preferably made of a material that suppresses the permeation of impurities such as external air components and moisture. By using such a material for the adhesive layer 164, the reliability of the display device 100 can be improved.

[0468] A structure in which the insulator 113 and the substrate 102 are bonded together via the resin layer 163 using the adhesive layer 164 is sometimes called a solid sealing structure. In addition, in the solid sealing structure, if the resin layer 163 has the function of bonding the insulator 113 and the substrate 102 together, similar to the adhesive layer 164, the adhesive layer 164 is not necessarily provided.

[0469] On the other hand, a structure in which the insulator 113 and the substrate 102 are bonded together using the adhesive layer 164 and filled with an inert gas instead of the resin layer 163 is sometimes called a hollow sealing structure (not shown). Examples of the inert gas include nitrogen and argon.

[0470] 28A , two or more adhesive layers may be stacked. For example, as shown in FIG. 28B , an adhesive layer 165 may be provided inside adhesive layer 164 (between adhesive layer 164 and resin layer 163). Stacking two or more adhesive layers can further suppress the permeation of impurities such as moisture, thereby further improving the reliability of display device 100.

[0471] Furthermore, a desiccant may be mixed into the adhesive layer 165. This allows the desiccant to adsorb moisture contained in the adhesive layer 164, the resin layer 163 formed inside the adhesive layer 165, the insulator, the conductor, and the EL layer, thereby improving the reliability of the display device 100.

[0472] Furthermore, although the display device 100 in FIG. 28B has a solid sealing structure, it may have a hollow sealing structure.

[0473] 28A and 28B, an inert liquid may be filled in place of the resin layer 163. As the inert liquid, for example, a fluorine-based inert liquid may be used.

[0474] <Modification of Display Device> One embodiment of the present invention is not limited to the above-described configuration, and the above-described configuration can be modified as appropriate depending on the situation. Modifications of the display device 100 in FIG. 24 will be described below with reference to FIGS. 29A to 30B . Note that FIGS. 29A to 30B illustrate only a portion of the pixel layer PXAL of the display device 100. Specifically, each of FIGS. 29A to 30B illustrates the insulator 111, the insulators positioned above the insulator 111, the conductors, the light-emitting device 150a, and the light-emitting device 150b. In particular, FIGS. 29A to 30B also illustrate the light-emitting device 150c, the conductor 121c, the layer 161c, the conductor 122c, and the EL layer 141c.

[0475] Note that, for example, the color of light emitted by the EL layer 141c may be different from the colors of light emitted by the EL layer 141a and the EL layer 141b. Furthermore, for example, the display device 100 may be configured such that the number of colors emitted by the light-emitting devices 150a to 150c is two. Furthermore, for example, the display device 100 may be configured such that the number of colors emitted by the light-emitting devices 150 is increased to four or more (not shown).

[0476] 29A , the display device 100 may have an EL layer 142 formed on the EL layers 141a to 141c. Specifically, for example, in FIG. 25A , when the EL layers 141a to 141c include the layer 4430 and the light-emitting layer 4411, the EL layer 142 may include the layer 4420. In this case, the layer 4420 included in the EL layer 142 functions as a common layer for the light-emitting devices 150a to 150c. Similarly, in FIG. 25C , when the EL layers 141a to 141c include the layer 4430, the light-emitting layer 4411, the light-emitting layer 4412, and the light-emitting layer 4413, the EL layer 142 includes the layer 4420, so that the layer 4420 included in the EL layer 142 functions as a common layer for the light-emitting devices 150a to 150c. Furthermore, for example, in FIG. 25D, when the EL layers 141a to 141c are configured to include the layer 4430, the light-emitting layer 4412, and the layer 4420 of the light-emitting unit 4400b, the intermediate layer 4440, and the layer 4430 and the light-emitting layer 4411 of the light-emitting unit 4400a, the EL layer 142 is configured to include the layer 4420 of the light-emitting unit 4400b, so that the layer 4420 of the light-emitting unit 4400a included in the EL layer 142 functions as a common layer in each of the light-emitting devices 150a to 150c.

[0477] Furthermore, for example, the insulator 113 may have a stacked structure of two or more layers instead of a single layer in the configuration of the display device 100. For example, the insulator 113 may have a three-layer stacked structure in which an insulator made of an inorganic material is applied as a first layer, an insulator made of an organic material is applied as a second layer, and an insulator made of an inorganic material is applied as a third layer. Figure 29B shows a cross-sectional view of a portion of the display device 100 in which the insulator 113 has a multilayer structure including the insulators 113a, 113b, and 113c, where the insulator 113a is an insulator made of an inorganic material, the insulator 113b is an insulator made of an organic material, and the insulator 113c is an insulator made of an inorganic material.

[0478] Furthermore, for example, a microcavity structure (microresonator structure) may be provided in each of the EL layers 141 a to 141 c as a configuration of the display device 100. The microcavity structure refers to a structure in which, for example, a light-transmitting and light-reflective conductive material is used for the conductor 122 that is the upper electrode (common electrode) and a light-reflective conductive material is used for the conductor 121 that is the lower electrode (pixel electrode), and the distance between the bottom surface of the light-emitting layer and the top surface of the lower electrode, that is, the film thickness of the layer 4430 in FIG. 25A , is set to a thickness corresponding to the wavelength of the color of light emitted by the light-emitting layer included in the EL layer 141.

[0479] For example, since light reflected by the lower electrode and returned (reflected light) causes significant interference with light directly incident on the upper electrode from the light-emitting layer (incident light), it is preferable to adjust the optical distance between the lower electrode and the light-emitting layer to (2n-1)λ / 4 (where n is a natural number greater than or equal to 1, and λ is the wavelength of the emitted light to be amplified). By adjusting this optical distance, the phases of the reflected light and incident light, each of which has a wavelength λ, can be matched, thereby further amplifying the light emitted from the light-emitting layer. On the other hand, if the reflected light and incident light have a wavelength other than λ, they will no longer match in phase, resulting in attenuation without resonance.

[0480] In the above structure, the EL layer may have a structure having multiple light-emitting layers or a structure having a single light-emitting layer.Furthermore, for example, the above-mentioned tandem light-emitting device structure may be combined with a microcavity structure.

[0481] The microcavity structure makes it possible to increase the light emission intensity of a specific wavelength in the front direction, thereby reducing power consumption. In particular, in the case of XR devices such as VR and AR, light from the light-emitting device is often incident on the eyes of a user wearing the device in the front direction, so it can be said that providing a microcavity structure in a display device for XR devices is preferable. Note that in the case of a display device that displays images using four sub-pixels of red, yellow, green, and blue, in addition to the brightness improvement effect of yellow emission, the microcavity structure that can be applied to all sub-pixels is suitable for each color wavelength, resulting in a display device with good characteristics.

[0482] 30A shows a cross-sectional view of a portion of the display device 100 having a microcavity structure, as an example. Furthermore, when the light-emitting device 150a has a light-emitting layer that emits blue (B) light, the light-emitting device 150b has a light-emitting layer that emits green (G), and the light-emitting device 150c has a light-emitting layer that emits red (R), as shown in FIG. 30A , it is preferable to increase the thickness of the EL layer 141a, the EL layer 141b, and the EL layer 141c in that order. Specifically, the thickness of the layer 4430 included in each of the EL layers 141a, 141b, and 141c can be determined according to the color of light emitted by each light-emitting layer. In this case, the layer 4430 included in the EL layer 141a is the thinnest, and the layer 4430 included in the EL layer 141c is the thickest.

[0483] Furthermore, for example, the display device 100 may include a colored layer (color filter). Fig. 30B shows, as an example, a configuration in which colored layers 166a, 166b, and 166c are included between the resin layer 163 and the substrate 102. Note that the colored layers 166a to 166c can be formed on the substrate 102, for example. Furthermore, when the light-emitting device 150a has a light-emitting layer that emits blue (B) light, the light-emitting device 150b has a light-emitting layer that emits green (G), and the light-emitting device 150c has a light-emitting layer that emits red (R), the colored layer 166a is blue, the colored layer 166b is green, and the colored layer 166c is red.

[0484] 30B can be constructed by bonding a substrate 102 provided with colored layers 166a to 166c to a substrate 310 on which light-emitting devices 150a to 150c have been formed, via a resin layer 163. The bonding is preferably performed so that the light-emitting device 150a and the colored layer 166a overlap, the light-emitting device 150b and the colored layer 166b overlap, and the light-emitting device 150c and the colored layer 166c overlap. By providing the colored layers 166a to 166c in the display device 100, for example, light emitted by the light-emitting device 150b does not exit above the substrate 102 via the colored layer 166a or the colored layer 166c, but exits above the substrate 102 via the colored layer 166b. In other words, since it is possible to block light from the light-emitting device 150 of the display device 100 in an oblique direction (the direction of the elevation angle when the top surface of the substrate 102 is considered to be a horizontal plane), it is possible to reduce the dependency of the display device 100 on the viewing angle, and it is possible to prevent a decrease in the display quality of the image displayed on the display device 100 when viewed from an oblique angle.

[0485] The colored layers 166a to 166c formed on the substrate 102 may be covered with a resin called an overcoat layer. Specifically, the display device 100 may be formed by laminating the resin layer 163, the overcoat layer, the colored layers 166a to 166c, and the substrate 102 in this order (not shown). Note that examples of the resin used for the overcoat layer include a thermosetting material that is light-transmitting and based on an acrylic resin or an epoxy resin.

[0486] Furthermore, for example, a black matrix (not shown) may be included in addition to the colored layers as part of the configuration of the display device 100. By providing a black matrix between the colored layers 166a and 166b, between the colored layers 166b and 166c, and between the colored layers 166c and 166a, it is possible to more effectively block light from the light-emitting device 150 of the display device 100 in an oblique direction (the direction of the elevation angle when the top surface of the substrate 102 is considered to be a horizontal plane), thereby more effectively preventing a decrease in the display quality of an image displayed on the display device 100 when the image is viewed obliquely.

[0487] 30B, when the display device has a colored layer, the light-emitting devices 150a to 150c included in the display device may all be light-emitting devices that emit white light (not shown). The light-emitting devices may have, for example, a single structure or a tandem structure.

[0488] Although the above-described structure of the display device 100 includes the conductors 121a to 121c as anodes and the conductor 122 as a cathode, the display device 100 may include the conductors 121a to 121c as cathodes and the conductor 122 as an anode. That is, in the manufacturing process described above, the stack order of the hole injection layer, the hole transport layer, the light-emitting layer, the electron transport layer, and the electron injection layer included in the EL layers 141a to 141c and the EL layer 142 may be reversed.

[0489] <Structural Example of Layer 161> Here, a cross-sectional structure of a region including the conductor 121, the layer 161, and their surroundings is shown for the display device 100. Note that the descriptions relating to Figures 31A to 31D also apply to the light-emitting devices 150a and 150b.

[0490] 24 and 26 to 30B show examples in which the top surface of layer 161 and the top surface of conductor 121 are roughly aligned, but the present invention is not limited to this. For example, as shown in Fig. 31A, the top surface of layer 161 may be higher than the top surface of conductor 121. In this case, the top surface of layer 161 has a shape that is gently bulging outward in a convex shape toward the center.

[0491] 31B, the upper surface of layer 161 may be lower than the upper surface of conductor 121. In this case, the upper surface of layer 161 has a gently sloping recessed shape that is concave toward the center.

[0492] 31C , when the upper surface of layer 161 is higher than the upper surface of conductor 121, the upper portion of layer 161 may be formed to extend beyond the recess formed in conductor 121. In this case, part of layer 161 may be formed to cover part of the generally flat region of conductor 121.

[0493] 31D, in the structure shown in Fig. 31C, a recess may be further formed in part of the upper surface of layer 161. The recess has a shape that is gently recessed toward the center.

[0494] <Structural Example of Insulator 162> Next, a cross-sectional structure of a region including the insulator 162 and its periphery in the display device 100 will be shown.

[0495] 32A shows an example in which the thicknesses of the EL layer 141a and the EL layer 141b are different from each other. The height of the top surface of the insulator 112 is the same or approximately the same as the height of the top surface of the EL layer 141a on the EL layer 141a side, and is the same or approximately the same as the height of the top surface of the EL layer 141b on the EL layer 141b side. The top surface of the insulator 112 has a gentle slope, with the EL layer 141a side being higher and the EL layer 141b side being lower. In this way, the heights of the insulators 112 and 162 are preferably the same as the height of the top surfaces of the adjacent EL layers. Alternatively, the top surface may have a flat portion that is the same as the height of the top surface of one of the adjacent EL layers.

[0496] 32B, the top surface of the insulator 162 has a region higher than the top surfaces of the EL layers 141a and 141b. The top surface of the insulator 112 has a shape that gently bulges outward toward the center.

[0497] 32C , the display device 100 has a region in which the top surface of the insulator 112 is higher than the top surfaces of the EL layers 141a and 141b. Furthermore, in a region including the insulator 162 and its periphery, the display device 100 has a first region located on at least one of the sacrificial layers 118 and 119. The first region is higher than the top surfaces of the EL layers 141a and 141b, and a part of the insulator 162 is formed in the first region. Furthermore, in a region including the insulator 162 and its periphery, the display device 100 has a second region located on at least one of the sacrificial layers 118 and 119. The second region is higher than the top surfaces of the EL layers 141a and 141b, and a part of the insulator 162 is formed in the second region.

[0498] 32D, the top surface of the insulator 162 has an area that is lower than the top surfaces of the EL layers 141a and 141b. The top surface of the insulator 162 has a gently sloping concave shape that is concave toward the center.

[0499] 32E, the upper surface of the insulator 112 has a region higher than the upper surface of the EL layer 141a and the upper surface of the EL layer 141b. That is, the insulator 112 protrudes from the surface on which the EL layer 141 is to be formed, forming a convex portion.

[0500] When forming the insulator 112, for example, if the insulator 112 is formed so that its height is aligned or approximately aligned with that of the sacrificial layer, the insulator 112 may be formed in a protruding shape, as shown in Figure 32E.

[0501] 32F, the upper surface of the insulator 112 has a region that is lower than the upper surfaces of the EL layers 141a and 141b. That is, the insulator 112 forms a recess on the surface where the EL layer 141 is to be formed.

[0502] In this way, the insulators 112 and 162 can be applied in various shapes.

[0503] <Configuration Example of Pixel Circuit> Here, a configuration example of a pixel circuit that can be provided in the pixel layer PXAL will be described.

[0504] 33A and 33B show a configuration example of a pixel circuit that can be provided in the pixel layer PXAL and a light-emitting device 150 connected to the pixel circuit. Also, FIG. 33A is a diagram showing the connections of each circuit element included in the pixel circuit 400 provided in the pixel layer PXAL, and FIG. 33B is a diagram schematically showing the hierarchical relationship of a circuit layer SICL including a drive circuit 30 and the like, a layer OSL including multiple transistors of the pixel circuit, and a layer EML including a light-emitting device 150. Note that the pixel layer PXAL of the display device 100 shown in FIG. 33B includes, as an example, a layer OSL and a layer EML. Also, the transistors 500A, 500B, 500C, and the like included in the layer OSL shown in FIG. 33B correspond to the transistor 200 in FIG. 24. Also, the light-emitting device 150 included in the layer EML shown in FIG. 33B corresponds to the light-emitting device 150a or the light-emitting device 150b in FIG. 24.

[0505] 33A and 33B includes a pixel circuit 400 including a transistor 500A, a transistor 500B, a transistor 500C, and a capacitor 600. The transistors 500A, 500B, and 500C can be, for example, transistors applicable to the transistor 200 described above. That is, the transistors 500A, 500B, and 500C can be Si transistors. Alternatively, the transistors 500A, 500B, and 500C can be, for example, transistors applicable to the transistor 500 described above. That is, the transistors 500A, 500B, and 500C can be OS transistors. In particular, when the transistors 500A, 500B, and 500C are OS transistors, each of the transistors 500A, 500B, and 500C preferably includes a back gate electrode. In this case, the back gate electrode may receive the same signal as the gate electrode, or a different signal from the gate electrode. Although the transistors 500A, 500B, and 500C each include a back gate electrode in FIGS. 33A and 33B, the transistors 500A, 500B, and 500C may not include a back gate electrode.

[0506] The transistor 500B includes a gate electrode electrically connected to the transistor 500A, a first electrode electrically connected to the light-emitting device 150, and a second electrode electrically connected to the wiring ANO. The wiring ANO is a wiring for applying a potential for supplying a current to the light-emitting device 150.

[0507] The transistor 500A has a first terminal electrically connected to the gate electrode of the transistor 500B, a second terminal electrically connected to the wiring SL that functions as a source line, and a gate electrode that has the function of controlling the conductive state or non-conductive state based on the potential of the wiring GL1 that functions as a gate line.

[0508] The transistor 500C includes a first terminal electrically connected to the wiring V0, a ​​second terminal electrically connected to the light-emitting device 150, and a gate electrode having a function of controlling the conductive state or non-conductive state based on the potential of the wiring GL2 functioning as a gate line. The wiring V0 is a wiring for applying a reference potential and a wiring for outputting a current flowing through the pixel circuit 400 to the drive circuit 30.

[0509] The capacitor 600 includes a conductive film electrically connected to the gate electrode of the transistor 500B and a conductive film electrically connected to the second electrode of the transistor 500C.

[0510] The light-emitting device 150 includes a first electrode electrically connected to the first electrode of the transistor 500B and a second electrode electrically connected to a wiring VCOM. The wiring VCOM is a wiring for applying a potential for supplying a current to the light-emitting device 150.

[0511] This allows the intensity of light emitted by light-emitting device 150 to be controlled in accordance with an image signal applied to the gate electrode of transistor 500B. Furthermore, the reference potential of wiring V0 applied via transistor 500C can suppress variations in the gate-source voltage of transistor 500B.

[0512] Furthermore, the wiring V0 can output a current amount that can be used to set pixel parameters. More specifically, the wiring V0 can function as a monitor line for outputting the current flowing through the transistor 500B or the current flowing through the light-emitting device 150 to the outside. The current output to the wiring V0 is converted into a voltage by a source follower circuit or the like and output to the outside. Alternatively, it can be converted into a digital signal by an A-D converter or the like and output to the arithmetic circuit 1350, arithmetic circuit MAC1, etc. described in the above embodiments.

[0513] In the configuration shown as an example in FIG. 33B , the wiring electrically connecting the pixel circuits 400 and the driver circuit 30 can be shortened, thereby reducing the wiring resistance of the wiring. This allows data to be written at high speed, enabling the display device 100 to be driven at high speed. This allows a sufficient frame period to be ensured even if the display device 100 has a large number of pixel circuits 400, thereby increasing the pixel density of the display device 100. Furthermore, increasing the pixel density of the display device 100 increases the resolution of the image displayed by the display device 100. For example, the pixel density of the display device 100 can be set to 1000 ppi or more, 5000 ppi or more, or 7000 ppi or more. Therefore, the display device 100 can be used as a display device for AR or VR, for example, and can be suitably applied to electronic devices such as HMDs, in which the display unit is close to the user.

[0514] 33A and 33B show an example of the pixel circuit 400 including three transistors in total, but the pixel circuit of the electronic device of one embodiment of the present invention is not limited to this. Below, a configuration example of a pixel circuit that can be used for the pixel circuit 400 will be described.

[0515] The pixel circuit 400A shown in Fig. 34A includes a transistor 500A, a transistor 500B, and a capacitor 600. Fig. 34A also illustrates a light-emitting device 150 connected to the pixel circuit 400A. The pixel circuit 400A is electrically connected to a wiring SL, a wiring GL, a wiring ANO, and a wiring VCOM.

[0516] The transistor 500A has a gate electrically connected to a wiring GL, one of its source and drain electrically connected to a wiring SL, and the other electrically connected to the gate of the transistor 500B and one electrode of the capacitor 600. The transistor 500B has one of its source and drain electrically connected to a wiring ANO, and the other electrically connected to the anode of the light-emitting device 150. The capacitor 600 has the other electrode electrically connected to the anode of the light-emitting device 150. The light-emitting device 150 has a cathode electrically connected to a wiring VCOM.

[0517] 34B has a configuration in which a transistor 500C is added to the pixel circuit 400A. A wiring V0 is electrically connected to the pixel circuit 400B.

[0518] The pixel circuit 400C shown in FIG. 34C is an example in which the transistors 500A and 500B in the pixel circuit 400A are transistors whose gates and back gates are electrically connected. The pixel circuit 400D shown in FIG. 34D is an example in which the same transistors are used in the pixel circuit 400B. This increases the current that the transistors can pass. Note that, although all the transistors in this example have a pair of gates electrically connected, this is not a limitation. Alternatively, a transistor having a pair of gates electrically connected to different wirings may be used. For example, reliability can be improved by using a transistor in which one of the gates is electrically connected to a source.

[0519] 35A has a configuration in which a transistor 500D is added to the pixel circuit 400B. The pixel circuit 400E is electrically connected to three wirings (a wiring GL1, a wiring GL2, and a wiring GL3) that function as gate lines.

[0520] The gate of the transistor 500D is electrically connected to a wiring GL3, one of the source and drain of the transistor 500D is electrically connected to the gate of the transistor 500B, and the other is electrically connected to a wiring V0. The gate of the transistor 500A is electrically connected to a wiring GL1, and the gate of the transistor 500C is electrically connected to a wiring GL2.

[0521] By simultaneously turning on the transistors 500C and 500D, the source and gate of the transistor 500B have the same potential, and the transistor 500B can be turned off. This forcibly cuts off the current flowing through the light-emitting device 150. Such a pixel circuit is suitable for use in a display method in which display periods and off periods are alternately provided.

[0522] 35B is an example in which a capacitor 600A is added to the pixel circuit 400E. The capacitor 600A functions as a storage capacitor.

[0523] 35C and 35D are examples in which transistors whose gates and back gates are electrically connected are applied to the pixel circuit 400E or 400F, respectively. Transistors whose gates and back gates are electrically connected are applied to transistors 500A, 500C, and 500D, and a transistor whose gate is electrically connected to its source is applied to transistor 500B.

[0524] <Top Schematic View and Schematic Cross-Section of Light-Emitting Device> Figure 36A is a top schematic view illustrating a configuration example in which a light-emitting device and a light-receiving device are arranged within one pixel in a display device 100 according to one embodiment of the present invention. The display device 100 includes a plurality of light-emitting devices 150R that emit red light, a plurality of light-emitting devices 150G that emit green light, a plurality of light-emitting devices 150B that emit blue light, and a plurality of light-receiving devices 160. In Figure 36A, to easily distinguish between the light-emitting devices 150, the symbols R, G, and B are assigned within the light-emitting region of each light-emitting device 150. Furthermore, the symbol PD is assigned within the light-receiving region of each light-receiving device 160.

[0525] The light-emitting devices 150R, 150G, 150B, and the light-receiving devices 160 are arranged in a matrix. FIG. 36A shows an example in which the light-emitting devices 150R, 150G, and 150B are arranged in the X direction, and the light-receiving devices 160 are arranged below them. FIG. 36A also shows an example in which the light-emitting devices 150 emitting light of the same color are arranged in the Y direction intersecting the X direction. In the display device 100 shown in FIG. 36A , a pixel 80 can be configured by, for example, a sub-pixel having the light-emitting device 150R, a sub-pixel having the light-emitting device 150G, and a sub-pixel having the light-emitting device 150B arranged in the X direction, and a sub-pixel having the light-receiving device 160 provided below these sub-pixels.

[0526] As the light-emitting device 150R, the light-emitting device 150G, and the light-emitting device 150B, 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 light-emitting materials that the EL elements have include fluorescent materials, phosphorescent materials, inorganic compounds (quantum dot materials, etc.), and materials that exhibit thermally activated delayed fluorescence (thermally activated delayed fluorescence (TADF) materials). Note that, as the TADF material, a material that is in thermal equilibrium between a singlet excited state and a triplet excited state may be used. Such TADF materials have a short emission lifetime (excitation lifetime), which can suppress a decrease in efficiency in the high-brightness region of the light-emitting element.

[0527] For example, a pn-type or pin-type photodiode can be used as the light-receiving device 160. The light-receiving device 160 functions as a photoelectric conversion element that detects light incident on the light-receiving device 160 and generates electric charges. The amount of electric charges generated is determined based on the amount of incident light.

[0528] In particular, it is preferable to use an organic photodiode having a layer containing an organic compound as the light-receiving device 160. 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.

[0529] In an electronic device according to one embodiment of the present invention, an organic EL element is used as the light-emitting device 150, and an organic photodiode is used as the light-receiving device 160. The organic EL element and the organic photodiode can be formed on the same substrate. Therefore, an organic photodiode can be built into a display device using an organic EL element. Note that the organic EL elements and the organic photodiode are preferably separated from each other by photolithography. This allows the distance between the light-emitting devices, between the organic photodiodes, and between the light-emitting device and the organic photodiode to be narrowed, thereby realizing a display device with a higher aperture ratio than when a shadow mask such as a metal mask is used.

[0530] 36A shows a conductor 122 that functions as a common electrode and a conductor 123 that functions as a connection electrode. Here, the conductor 123 is electrically connected to the conductor 122. The conductor 123 is provided outside the display section in which the light-emitting device 150 and the light-receiving device 160 are arranged. Also in FIG. 36A, the conductor 122 having an area that overlaps with the light-emitting device 150, the light-receiving device 160, and the conductor 123 is shown by dashed lines.

[0531] The conductor 123 can be provided along the outer periphery of the display unit. For example, it may be provided along one side of the outer periphery of the display unit, or it may be provided over two or more sides of the outer periphery of the display unit. That is, when the top surface of the display unit has a rectangular shape, the top surface of the conductor 123 can have a strip-like, L-shaped, U-shaped (square bracket-shaped), square-shaped, or the like shape.

[0532] Fig. 36B is a schematic top view showing an example of the configuration of display device 100, which is a modification of display device 100 shown in Fig. 36A. Display device 100 shown in Fig. 36B differs from display device 100 shown in Fig. 36A in that it includes light-emitting device 150IR that emits infrared light. Light-emitting device 150IR can emit, for example, near-infrared light (light with a wavelength of 750 nm or more and 1300 nm or less).

[0533] 36B, in addition to light-emitting devices 150R, 150G, and 150B, light-emitting device 150IR is arranged in the X direction, and light-receiving device 160 is arranged below light-emitting device 150IR. In addition, light-receiving device 160 has a function of detecting infrared light.

[0534] Fig. 37A is a cross-sectional view corresponding to dashed dotted line A1-A2 in Fig. 36A, and Fig. 37B is a cross-sectional view corresponding to dashed dotted line B1-B2 in Fig. 36A. Fig. 37C is a cross-sectional view corresponding to dashed dotted line C1-C2 in Fig. 36A, and Fig. 37D is a cross-sectional view corresponding to dashed dotted line D1-D2 in Fig. 36A. Light-emitting device 150R, light-emitting device 150G, light-emitting device 150B, and light-receiving device 160 are provided on insulator 111. Furthermore, when display device 100 includes light-emitting device 150IR, light-emitting device 150IR is provided on insulator 111.

[0535] 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.

[0536] Fig. 37A shows an example of the cross-sectional configuration of light-emitting device 150R, light-emitting device 150G, and light-emitting device 150B in Fig. 36A. Also, Fig. 37B shows an example of the cross-sectional configuration of light-receiving device 160 in Fig. 36A.

[0537] The light-emitting device 150R has a conductor 121R functioning as a pixel electrode, 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 conductor 122. The light-emitting device 150G has a conductor 121G functioning as a pixel electrode, 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 conductor 122. The light-emitting device 150B has a conductor 121B functioning as a pixel electrode, 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 conductor 122. The light-receiving device 160 has a conductor 121PD functioning as a pixel electrode, a hole transport layer 86PD, a light-receiving layer 90, an electron transport layer 88PD, a common layer 89, and a conductor 122.

[0538] The conductor 121R, the conductor 121G, and the conductor 121B can be, for example, the conductor 121a, the conductor 121b, and the conductor 121c shown in FIGS. 29A to 30B.

[0539] The common layer 89 functions as an electron injection layer in the light-emitting device 150. On the other hand, the common layer 89 functions as an electron transport layer in the light-receiving device 160. Therefore, the light-receiving device 160 does not need to have the electron transport layer 88PD.

[0540] 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.

[0541] The conductor 121, 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 conductor 122 are provided in common to the light-emitting device 150R, the light-emitting device 150G, the light-emitting device 150B, and the light-receiving device 160.

[0542] 37A , the light-emitting device 150 and the light-receiving device 160 may have a hole-blocking layer and an electron-blocking layer. The light-emitting device 150 and the light-receiving device 160 may also have a layer containing a bipolar substance (a substance with high electron-transporting and hole-transporting properties).

[0543] The insulating layer 92 is provided so as to cover the end of the conductor 121R, the end of the conductor 121G, the end of the conductor 121B, and the end of the conductor 121PD. The end of the insulating layer 92 is preferably tapered. Note that the insulating layer 92 does not have to be provided if it is not necessary.

[0544] For example, the hole injection layer 85R, the hole injection layer 85G, the hole injection layer 85B, and the hole transport layer 86PD each have a region in contact with the upper surface of the conductor 121 and a region in contact with the surface of the insulating layer 92. Furthermore, the end of the hole injection layer 85R, the end of the hole injection layer 85G, the end of the hole injection layer 85B, and the end of the hole transport layer 86PD are located on the insulating layer 92.

[0545] Furthermore, 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 device 150 and the light-receiving device 160.

[0546] 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.

[0547] In addition, a protective layer 91 is provided on the conductor 122. The protective layer 91 has a function of preventing impurities such as water from diffusing from above into each light-emitting element.

[0548] 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 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.

[0549] Alternatively, the protective layer 91 may be a laminated film of an inorganic insulating film and an organic insulating film. 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, and a lens array) is provided above the protective layer 91, the influence of uneven shapes caused by the structure below can be reduced, which is preferable.

[0550] 37A illustrates a configuration in which, from bottom to top, the light-emitting device 150 includes a conductor 121, 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 conductor 122, and the light-receiving device 160 includes, from bottom to top, a conductor 121PD, a hole-transport layer 86PD, a light-receiving layer 90, an electron-transport layer 88PD, the common layer 89, and a conductor 122. However, the configuration of a light-emitting device or a light-receiving device according to one embodiment of the present invention is not limited to this. For example, the light-emitting device 150 may include, from bottom to top, a conductor functioning as 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 conductor functioning as a common electrode, and the light-receiving device 160 may include, from bottom to top, a conductor functioning as a pixel electrode, an electron-transport layer, a light-receiving layer, a hole-transport layer, and a conductor functioning as a common electrode. In this case, the hole injection layer of the light-emitting device 150 can be a common layer, and the common layer can be provided between the hole transport layer and the common electrode of the light-receiving device 160. Furthermore, in the light-emitting device 150, the electron injection layer can be separated for each element.

[0551] Incidentally, when the sensor IS included in the electronic device HMD described in the first embodiment is an imaging device, the sensor IS can be the light receiving device 160 shown in Fig. 36A etc. In other words, by applying the configuration example of the arrangement of the light emitting device and the light receiving device shown in Fig. 36A to the display unit DSP, the electronic device HMD described in configuration example 4 can be configured.

[0552] <Pixel Layout> Here, a pixel layout different from the pixel layout shown in Fig. 36 will be described. There are no particular limitations on the arrangement of sub-pixels, and various methods can be applied. Examples of the arrangement of sub-pixels include a stripe arrangement, an S-stripe arrangement, a matrix arrangement, a delta arrangement, a Bayer arrangement, and a pentile arrangement.

[0553] Examples of the top surface shape of the subpixel include polygons such as triangles, quadrilaterals (including rectangles and squares), and pentagons, as well as polygons with rounded corners, ellipses, and circles. Here, the top surface shape of the subpixel corresponds to the top surface shape of the light-emitting region of the light-emitting device.

[0554] A stripe arrangement is applied to the pixel 80 shown in Fig. 38A. The pixel 80 shown in Fig. 38A is composed of three subpixels: subpixel 80a, subpixel 80b, and subpixel 80c. For example, as shown in Fig. 39A, the subpixel 80a may be a red subpixel R, the subpixel 80b may be a green subpixel G, and the subpixel 80c may be a blue subpixel B.

[0555] An S-stripe arrangement is applied to the pixel 80 shown in Fig. 38B. The pixel 80 shown in Fig. 38B is composed of three subpixels: subpixel 80a, subpixel 80b, and subpixel 80c. For example, as shown in Fig. 39B, the subpixel 80a may be a blue subpixel B, the subpixel 80b may be a red subpixel R, and the subpixel 80c may be a green subpixel G.

[0556] 38C shows an example in which subpixels of each color are arranged in a zigzag pattern. Specifically, when viewed from above, the positions of the upper edges of two subpixels aligned in the column direction (e.g., subpixels 80a and 80b, or subpixels 80b and 80c) are misaligned. For example, as shown in FIG. 39C , subpixel 80a may be a red subpixel R, subpixel 80b may be a green subpixel G, and subpixel 80c may be a blue subpixel B.

[0557] The pixel 80 shown in FIG. 38D includes a subpixel 80a having a generally trapezoidal top surface shape with rounded corners, a subpixel 80b having a generally triangular top surface shape with rounded corners, and a subpixel 80c having a generally rectangular or hexagonal top surface shape with rounded corners. Furthermore, the subpixel 80a has a larger light-emitting area than the subpixel 80b. In this manner, the shape and size of each subpixel can be determined independently. For example, the more reliable the light-emitting device, the smaller the size can be. For example, as shown in FIG. 39D, the subpixel 80a may be a green subpixel G, the subpixel 80b may be a red subpixel R, and the subpixel 80c may be a blue subpixel B.

[0558] The pixels 70A and 70B shown in Figure 38E are arranged in a Pentile array. Figure 38E shows an example in which pixel 70A having subpixels 80a and 80b and pixel 70B having subpixels 80b and 80c are arranged alternately. For example, as shown in Figure 39E, subpixel 80a may be a red subpixel R, subpixel 80b may be a green subpixel G, and subpixel 80c may be a blue subpixel B.

[0559] Pixels 70A and 70B shown in Figures 38F and 38G are arranged in a delta configuration. Pixel 70A has two subpixels (subpixel 80a and subpixel 80b) in the top row (first row) and one subpixel (subpixel 80c) in the bottom row (second row). Pixel 70B has one subpixel (subpixel 80c) in the top row (first row) and two subpixels (subpixel 80a and subpixel 80b) in the bottom row (second row). For example, as shown in Figure 39F, subpixel 80a may be a red subpixel R, subpixel 80b may be a green subpixel G, and subpixel 80c may be a blue subpixel B.

[0560] FIG. 38F shows an example in which each subpixel has a substantially rectangular top surface shape with rounded corners, and FIG. 38G shows an example in which each subpixel has a circular top surface shape.

[0561] In photolithography, the finer the pattern to be processed, the more significant the effect of light diffraction becomes. This reduces the fidelity of the photomask pattern when it is transferred by exposure, making it difficult to process the resist mask into the desired shape. Therefore, even if the photomask pattern is rectangular, it is likely to have rounded corners. As a result, the top surface shape of the subpixel may become a polygon with rounded corners, an ellipse, or a circle.

[0562] Furthermore, in a manufacturing method of a display device according to one embodiment of the present invention, the EL layer is processed into an island shape using a resist mask. The resist film formed on the EL layer needs to be cured at a temperature lower than the heat resistance temperature of the EL layer. Therefore, depending on the heat resistance temperature of the material for the EL layer and the curing temperature of the resist material, the resist film may not be cured sufficiently. A resist film that is not cured sufficiently may have a shape that deviates from the desired shape during processing. As a result, the top surface shape of the EL layer may become a polygon with rounded corners, an ellipse, or a circle. For example, when a resist mask with a square top surface shape is formed, a resist mask with a circular top surface shape may be formed, resulting in a circular top surface shape of the EL layer.

[0563] In order to form the top surface of the EL layer into a desired shape, a technique for correcting a mask pattern in advance (OPC (Optical Proximity Correction) technique) may be used so that the design pattern and the transfer pattern coincide with each other. Specifically, the OPC technique adds a correction pattern to the corners of figures on the mask pattern.

[0564] The pixel 80 shown in FIGS. 40A to 40C is configured in a stripe arrangement.

[0565] Figure 40A is an example in which each subpixel has a rectangular top surface shape, Figure 40B is an example in which each subpixel has a top surface shape that is a combination of two semicircles and a rectangle, and Figure 40C is an example in which each subpixel has an elliptical top surface shape.

[0566] The pixels 80 shown in FIGS. 40D to 40F are arranged in a matrix.

[0567] Figure 40D is an example in which each subpixel has a square top surface shape, Figure 40E is an example in which each subpixel has an approximately square top surface shape with rounded corners, and Figure 40F is an example in which each subpixel has a circular top surface shape.

[0568] The pixel 80 shown in Figures 40A to 40F is composed of four subpixels: subpixel 80a, subpixel 80b, subpixel 80c, and subpixel 80d. The subpixels 80a, 80b, 80c, and 80d each emit light of a different color. For example, as shown in Figures 41A and 41B, the subpixels 80a, 80b, 80c, and 80d can be red, green, blue, and white subpixels, respectively. Alternatively, the subpixels 80a, 80b, 80c, and 80d can be red, green, blue, and infrared emitting subpixels, respectively.

[0569] The subpixel 80d includes a light-emitting device. For example, the light-emitting device includes a pixel electrode, an EL layer, and a conductor 123 that functions as a common electrode. Note that the pixel electrode may be formed using a material similar to that of the conductor 121a, the conductor 121b, the conductor 121c, the conductor 122a, the conductor 122b, or the conductor 122c. The EL layer may be formed using a material similar to that of the EL layer 141a, the EL layer 141b, or the EL layer 141c, for example.

[0570] FIG. 40G shows an example in which one pixel 80 is configured with two rows and three columns. The pixel 80 has three subpixels (subpixels 80a, 80b, and 80c) in the top row (first row) and three subpixels 80d in the bottom row (second row). In other words, the pixel 80 has subpixels 80a and 80d in the left column (first column), subpixels 80b and 80d in the center column (second column), and subpixels 80c and 80d in the right column (third column). As shown in FIG. 40G, by aligning the subpixels in the top row and bottom row, it is possible to efficiently remove dust and other impurities that may occur during the manufacturing process. Therefore, a display device with high display quality can be provided.

[0571] 40H shows an example in which one pixel 80 is configured with two rows and three columns. The pixel 80 has three subpixels (subpixels 80a, 80b, and 80c) in the top row (first row) and one subpixel (subpixel 80d) in the bottom row (second row). In other words, the pixel 80 has the subpixel 80a in the left column (first column), the subpixel 80b in the center column (second column), the subpixel 80c in the right column (third column), and further has the subpixel 80d across these three columns.

[0572] In the pixel 80 shown in Figures 40G and 40H, for example, as shown in Figures 41C and 41D, the subpixel 80a can be a red subpixel R, the subpixel 80b can be a green subpixel G, the subpixel 80c can be a blue subpixel B, and the subpixel 80d can be a white subpixel W.

[0573] The display device according to one embodiment of the present invention may include a light-receiving device in a pixel.

[0574] Of the four sub-pixels included in pixel 80 shown in FIG. 40G, three may be configured to have a light-emitting device, and the remaining one may be configured to have a light-receiving device.

[0575] The light receiving device may be, for example, a pn-type or pin-type photodiode. The light receiving device functions as a photoelectric conversion device (also called a photoelectric conversion element) that detects light incident on the light receiving device and generates electric charges. The amount of electric charges generated by the light receiving device is determined based on the amount of light incident on the light receiving device.

[0576] In particular, it is preferable to use an organic photodiode having a layer containing an organic compound as the light-receiving device. Organic photodiodes can be easily made thin, lightweight, and large in area, and have a high degree of freedom in shape and design, making them applicable to a variety of display devices.

[0577] In one embodiment of the present invention, an organic EL device is used as the light-emitting device, and an organic photodiode is used as the light-receiving device. The organic EL device and the organic photodiode can be formed on the same substrate. Therefore, the organic photodiode can be built into a display device using the organic EL device.

[0578] The light-receiving device has an active layer that functions as at least a photoelectric conversion layer between a pair of electrodes. In this specification and the like, one of the pair of electrodes may be referred to as a pixel electrode and the other as a common electrode.

[0579] For example, the subpixels 80a, 80b, and 80c may be subpixels of three colors, R, G, and B, respectively, and the subpixel 80d may be a subpixel having a light-receiving device. In this case, the fourth layer has at least an active layer.

[0580] Of the pair of electrodes that a light-receiving device has, one electrode functions as an anode and the other electrode functions as a cathode. The following describes an example in which the pixel electrode functions as the anode and the common electrode functions as the cathode. The light-receiving device can detect light incident on the light-receiving device, generate electric charges, and extract them as a current by applying a reverse bias between the pixel electrode and the common electrode. Alternatively, the pixel electrode may function as a cathode and the common electrode may function as an anode.

[0581] The same manufacturing method as for the light-emitting device can be applied to the light-receiving device. The island-shaped active layer (also called a photoelectric conversion layer) of the light-receiving device is not formed by a metal mask pattern, but is formed by forming a film that will become the active layer on the entire surface and then processing it, so that the island-shaped active layer can be formed with a uniform thickness. Furthermore, by providing a sacrificial layer on the active layer, damage to the active layer during the manufacturing process of the display device can be reduced, and the reliability of the light-receiving device can be improved.

[0582] Here, a layer shared by a light-receiving device and a light-emitting device may have different functions in the light-emitting device and in the light-receiving device. In this specification, components may be referred to based on their functions in the light-emitting device. For example, a hole injection layer functions as a hole injection layer in the light-emitting device and as a hole transport layer in the light-receiving device. Similarly, an electron injection layer functions as an electron injection layer in the light-emitting device and as an electron transport layer in the light-receiving device. Furthermore, a layer shared by a light-receiving device and a light-emitting device may have the same function in the light-emitting device and in the light-receiving device. A hole transport layer functions as a hole transport layer in both the light-emitting device and the light-receiving device, and an electron transport layer functions as an electron transport layer in both the light-emitting device and the light-receiving device.

[0583] The active layer of the light-receiving device includes a semiconductor. Examples of the semiconductor include inorganic semiconductors such as silicon and organic semiconductors containing organic compounds. In this embodiment, an example in which an organic semiconductor is used as the semiconductor of the active layer is shown. Using an organic semiconductor is preferable because the light-emitting layer and the active layer can be formed by the same method (e.g., vacuum deposition), allowing the use of a common manufacturing device.

[0584] The n-type semiconductor material of the active layer is fullerene (e.g., C ６０ , C ７０ Examples of electron-accepting organic semiconductor materials include fullerene derivatives and fullerenes. Fullerenes have a soccer ball-like shape, which is energetically stable. Fullerenes have deep (low) HOMO and LUMO levels. Because fullerenes have a deep LUMO level, they have extremely high electron-accepting (acceptor) properties. Normally, when 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 allow charge separation to occur quickly and efficiently, making them useful as light-receiving devices. C ６０ , C ７０ Both have a wide absorption band in the visible light region, and C７０ 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).

[0585] Furthermore, examples of n-type semiconductor materials include metal complexes having a quinoline skeleton, metal complexes having a benzoquinoline skeleton, metal complexes having an oxazole skeleton, metal complexes having a thiazole skeleton, oxadiazole derivatives, triazole derivatives, imidazole derivatives, oxazole derivatives, thiazole derivatives, phenanthroline derivatives, quinoline derivatives, benzoquinoline derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, naphthalene derivatives, anthracene derivatives, coumarin derivatives, rhodamine derivatives, triazine derivatives, and quinone derivatives.

[0586] Examples of p-type semiconductor materials contained in the active layer include electron-donating organic semiconductor materials such as copper(II) phthalocyanine (CuPc), tetraphenyldibenzoperiflanethene (DBP), zinc phthalocyanine (ZnPc), tin phthalocyanine (SnPc), and quinacridone.

[0587] Examples of p-type semiconductor materials include carbazole derivatives, thiophene derivatives, furan derivatives, and compounds having an aromatic amine skeleton. Examples of p-type semiconductor materials include naphthalene derivatives, anthracene derivatives, pyrene derivatives, triphenylene derivatives, fluorene derivatives, pyrrole derivatives, benzofuran derivatives, benzothiophene derivatives, indole derivatives, dibenzofuran derivatives, dibenzothiophene derivatives, indolocarbazole derivatives, porphyrin derivatives, phthalocyanine derivatives, naphthalocyanine derivatives, quinacridone derivatives, polyphenylenevinylene derivatives, polyparaphenylene derivatives, polyfluorene derivatives, polyvinylcarbazole derivatives, and polythiophene derivatives.

[0588] 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.

[0589] 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.

[0590] For example, the active layer is preferably formed by co-evaporating an n-type semiconductor and a p-type semiconductor, or may be formed by laminating an n-type semiconductor and a p-type semiconductor.

[0591] The light-receiving device may further include a layer containing a substance with high hole-transporting properties, a substance with high electron-transporting properties, or a bipolar substance (a substance with high electron-transporting properties and high hole-transporting properties) as a layer other than the active layer. Furthermore, without being limited to the above, the light-receiving device may further include a layer containing one or more materials selected from a substance with high hole-injecting properties, a hole-blocking material, a material with high electron-injecting properties, and an electron-blocking material.

[0592] The light-receiving device may be made of either a low-molecular-weight compound or a high-molecular-weight compound, and may contain an inorganic compound. The layers constituting the light-receiving device may be formed by a vapor deposition method (including a vacuum vapor deposition method), a transfer method, a printing method, an inkjet method, or a coating method.

[0593] For example, the hole transport material may be a polymer compound such as poly(3,4-ethylenedioxythiophene) / poly(styrenesulfonic acid) (PEDOT / PSS), or an inorganic compound such as molybdenum oxide or copper iodide (CuI), while the electron transport material may be an inorganic compound such as zinc oxide (ZnO).

[0594] The active layer can be formed using a polymer compound such as Poly[[4,8-bis[5-(2-ethylhexyl)-2-thienyl]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl]-2,5-thiophenediyl[5,7-bis(2-ethylhexyl)-4,8-dioxo-4H,8H-benzo[1,2-c:4,5-c']dithiophene-1,3-diyl]] polymer (abbreviated as PBDB-T) or a PBDB-T derivative, which functions as a donor. For example, a method of dispersing an acceptor material in PBDB-T or a PBDB-T derivative can be used.

[0595] The active layer may also contain a mixture of three or more materials. 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.

[0596] In a display device having a light-emitting device and a light-receiving device in each pixel, the pixel has a light-receiving function, so that it is possible to detect contact or proximity of an object while displaying an image. For example, in addition to displaying an image using all of the sub-pixels of the display device, some of the sub-pixels can emit light as a light source and the remaining sub-pixels can display an image.

[0597] A display device according to one embodiment of the present invention has a display portion in which light-emitting devices are arranged in a matrix, and can display an image on the display portion. Furthermore, light-receiving devices are arranged in a matrix on the display portion, and the display portion has an imaging function and / or a sensing function in addition to an image display function. The display portion can be used as an image sensor or a touch sensor. That is, by detecting light in the display portion, an image can be captured or the proximity or contact of an object (such as a finger, a hand, or a pen) can be detected. Furthermore, the display device according to one embodiment of the present invention can use a light-emitting device as a light source for a sensor. Therefore, a light-receiving portion and a light source are not required separately from the display device, and the number of components in an electronic device can be reduced.

[0598] In a display device of one embodiment of the present invention, when light emitted from a light-emitting device included in a display portion is reflected (or scattered) by an object, the light-receiving device can detect the reflected light (or scattered light). Therefore, imaging or touch detection is possible even in a dark place.

[0599] When the light receiving device is used as an image sensor, the display device can capture an image using the light receiving device. For example, the display device of the present embodiment can be used as a scanner.

[0600] For example, an image sensor can be used to acquire data related to biometric information such as fingerprints and palm prints. That is, a biometric authentication sensor can be built into the display device. By building a biometric authentication sensor into the display device, the number of components in the electronic device can be reduced compared to when a biometric authentication sensor is provided separately from the display device, and the electronic device can be made smaller and lighter.

[0601] Furthermore, when the light-receiving device is used as a touch sensor, the display device can detect the proximity or contact of an object using the light-receiving device.

[0602] The pixel shown in FIGS. 42A to 42D has subpixels G, B, R, and PS.

[0603] The pixels shown in Fig. 42A are arranged in a stripe pattern, while the pixels shown in Fig. 42B are arranged in a matrix pattern.

[0604] 42C and 42D show an example in which one pixel is arranged across two rows and three columns. The top row (first row) has three subpixels (subpixel G, subpixel B, and subpixel R). In FIG. 42C, the bottom row (second row) has three subpixels PS. On the other hand, in FIG. 42D, the bottom row (second row) has two subpixels PS. By aligning the subpixels in the top and bottom rows as shown in FIG. 42C, it is possible to efficiently remove dust and other impurities that may occur during the manufacturing process. Therefore, a display device with high display quality can be provided. The subpixel layout is not limited to the configurations shown in FIGS. 42A to 42D.

[0605] Each of the subpixels R, G, and B has a light-emitting device that emits white light. In the subpixels R, G, and B, a corresponding colored layer is provided so as to overlap the light-emitting device.

[0606] The subpixels PS each have a light receiving device. The wavelength of light detected by the subpixels PS is not particularly limited.

[0607] The light receiving device included in the subpixel PS preferably detects visible light, for example, one or more of blue, purple, blue-purple, green, yellow-green, yellow, orange, and red. The light receiving device included in the subpixel PS may also detect infrared light.

[0608] The display device 100 shown in FIG. 42E has, between a substrate 351 and a substrate 359, a layer 353 having a light-receiving device, a functional layer 355, and a layer 357 having a light-emitting device.

[0609] The functional layer 355 includes a circuit for driving the light-receiving device and a circuit for driving the light-emitting device. The functional layer 355 may be provided with, for example, a switch, a transistor, a capacitor, a resistor, wiring, and a terminal. Note that when the light-emitting device and the light-receiving device are driven by a passive matrix method, a configuration without a switch and a transistor may be used.

[0610] 42E , light emitted from the light-emitting devices in the layer 357 having the light-emitting devices is reflected by the human eye and its surroundings, and the reflected light is detected by the light-receiving devices in the layer 353 having the light-receiving devices. This makes it possible to detect information about the surroundings, surface, or inside of the human eye (for example, the number of blinks, eyeball movement, and eyelid movement).

[0611] The insulators, conductors, and semiconductors disclosed in this specification and the like can be formed by a PVD (Physical Vapor Deposition) method or a CVD (Chemical Vapor Deposition) method. Examples of PVD methods include sputtering, resistance heating evaporation, electron beam evaporation, and PLD (Pulsed Laser Deposition). Examples of CVD methods include plasma CVD and thermal CVD. In particular, examples of thermal CVD methods include MOCVD (Metal Organic Chemical Vapor Deposition) and ALD (Atomic Layer Deposition).

[0612] The thermal CVD method is a film formation method that does not use plasma, and therefore has the advantage that defects caused by plasma damage are not generated.

[0613] In the thermal CVD method, a source gas and an oxidizing agent are simultaneously fed into a chamber, the chamber is kept at atmospheric pressure or reduced pressure, and the reaction occurs near or on a substrate, resulting in deposition on the substrate, thereby forming a film.

[0614] Alternatively, the ALD method may be used to deposit a film by sequentially introducing source gases for reaction into a chamber under atmospheric or reduced pressure and repeating this gas introduction sequence. For example, two or more source gases are sequentially supplied to the chamber by switching between switching valves (also called high-speed valves). An inert gas (e.g., argon or nitrogen) is introduced simultaneously with or after the first source gas to prevent mixing of the multiple source gases, followed by the introduction of the second source gas. When an inert gas is introduced simultaneously, the inert gas acts as a carrier gas, and may also be introduced simultaneously with the introduction of the second source gas. Alternatively, instead of introducing an inert gas, the first source gas may be evacuated by vacuum evacuation before the introduction of the second source gas. The first source gas adsorbs on the substrate surface to form a first thin layer, which then reacts with the second source gas introduced later, resulting in the second thin layer being deposited on the first thin layer to form a thin film. Repeating this gas introduction sequence multiple times while controlling the gas introduction sequence until the desired thickness is achieved allows the formation of a thin film with excellent step coverage. The thickness of the thin film can be adjusted by changing the number of times the gas introduction sequence is repeated, allowing for precise film thickness adjustment, making this method suitable for fabricating fine FETs.

[0615] Thermal CVD methods such as MOCVD and ALD can form various films such as metal films, semiconductor films, and inorganic insulating films disclosed in the embodiments described above. For example, when forming an In—Ga—Zn—O film, trimethylindium (In(CH ３ ) ３ ), trimethylgallium (Ga(CH ３ ) ３ ), and dimethylzinc (Zn(CH ３ ) ２ In addition, the combination is not limited to these, and trimethylgallium may be replaced with triethylgallium (Ga(C ２ H ５ ) ３ ) can also be used, and diethyl zinc (Zn(C) ２ H ５ ) ２ ) can also be used.

[0616] For example, when a hafnium oxide film is formed using a film formation apparatus that utilizes ALD, a solvent and a liquid containing a hafnium precursor compound (e.g., hafnium alkoxide, tetrakisdimethylamidohafnium (TDMAH), Hf[N(CH ３ ) ２ ] ４ The raw material gas is a vaporized hafnium amide (such as ozone) as an oxidizer. ３ ) Two types of gases are used. Other materials include tetrakis(ethylmethylamido)hafnium.

[0617] For example, when an aluminum oxide film is formed using a film formation apparatus that uses ALD, a liquid containing a solvent and an aluminum precursor compound (e.g., trimethylaluminum (TMA), Al(CH ３ ) ３ )) as a raw material gas, and H as an oxidant. ２ Two types of gases are used: O. Other materials include tris(dimethylamido)aluminum, triisobutylaluminum, and aluminum tris(2,2,6,6-tetramethyl-3,5-heptanedionate).

[0618] For example, when a silicon oxide film is formed using a film forming apparatus that uses ALD, hexachlorodisilane is adsorbed on the film forming surface, and an oxidizing gas (O ２ , nitrous oxide) radicals are supplied to react with the adsorbate.

[0619] For example, when a tungsten film is formed using a film forming apparatus that uses ALD, WF ６ Gas and B ２ H ６ The gases are introduced repeatedly in sequence to form an initial tungsten film, and then WF ６ Gas and H ２ The gases are introduced repeatedly in sequence to form a tungsten film. ２ H ６ Instead of gas, SiH ４ A gas may also be used.

[0620] For example, when an In—Ga—Zn—O film is formed as an oxide semiconductor film by a film formation apparatus using ALD, a precursor (generally, it may be called, for example, a precursor or a metal precursor) and an oxidizing agent (generally, it may be called, for example, a reactant or a non-metal precursor) are sequentially and repeatedly introduced to form the oxide semiconductor film. Specifically, for example, a precursor, In(CH ３ ) ３ gas and oxidizer O ３ The gas is introduced to form an In—O layer, and then the precursor Ga(CH ３ ) ３ gas and oxidizer O ３ The gas is introduced to form a GaO layer, and then the precursor Zn(CH ３ ) ２ gas and oxidizer O ３ The gas is introduced to form a ZnO layer. Note that the order of these layers is not limited to this example. Also, these gases may be used to form a mixed oxide layer such as an In—Ga—O layer, an In—Zn—O layer, or a Ga—Zn—O layer. Note that O ３ Instead of gas, H obtained by bubbling water with an inert gas such as Ar ２ O gas may be used, but O gas containing no H ３ It is preferable to use In(CH ３ ) ３ Instead of gas, In(C ２ H ５ ) ３ Gas may also be used. ３ ) ３ Instead of gas, Ga(C ２ H ５ ) ３ Gas may also be used. ３ ) ２ Gas may also be used.

[0621] The screen ratio (aspect ratio) of the display unit included in the electronic device of one embodiment of the present invention is not particularly limited. For example, the display unit can support various screen ratios such as 1:1 (square), 4:3, 16:9, and 16:10.

[0622] The shape of the display unit included in the electronic device of one embodiment of the present invention is not particularly limited. For example, the display unit can have various shapes such as a rectangular shape, a polygonal shape (e.g., an octagonal shape), a circular shape, and an elliptical shape.

[0623] Note that this embodiment mode can be appropriately combined with other embodiment modes described in this specification.

[0624] Embodiment 4 In this embodiment, a display module that can be applied to an electronic device of one embodiment of the present invention will be described.

[0625] <Configuration Example of Display Module> First, a display module including a display device that can be applied to an electronic device of one embodiment of the present invention will be described.

[0626] 43A shows a perspective view of a display module 1280. The display module 1280 includes the display device 100 and an FPC 1290.

[0627] The display module 1280 includes a substrate 1291 and a substrate 1292. The display module 1280 includes a display portion 1281. The display portion 1281 is a region for displaying an image in the display module 1280, and is a region where light from each pixel provided i...

Claims

1. A visual display device comprising: a display unit for a right eye; a display unit for a left eye; a transmission unit for a right eye; a transmission unit for a left eye; a receiving unit; and a control circuit; the right-eye transmitter and the left-eye transmitter have a function of generating a first ultrasonic wave of a first frequency and a function of transmitting a first electrical signal according to the first frequency to the control circuit; the receiving unit has a function of receiving a second ultrasonic wave of a second frequency that is the first ultrasonic wave reflected by an object, a function of generating a second electrical signal according to the second frequency, and a function of transmitting the second electrical signal to the control circuit; The object is at least one selected from a retinal blood vessel of the user's eye and a blood vessel included in the fundus, the control circuit has a function of calculating a blood flow velocity of the retinal blood vessel and one or more selected from the blood vessels using the first electrical signal and the second electrical signal, and a function of transmitting a third electrical signal corresponding to the blood flow velocity to the display unit for the right eye and the display unit for the left eye; the display unit for the right eye and the display unit for the left eye have a function of receiving the third electrical signal and displaying the blood flow velocity, When viewed from the front, the right eye transmitter, the right eye of the user, the receiver, the left eye of the user, and the left eye transmitter are arranged to be aligned in one direction. electronic equipment.

2. In claim 1, An audio output unit is provided, The control circuit has a function of transmitting a fourth electrical signal corresponding to the blood flow velocity to the audio output unit, The audio output unit has a function of receiving the fourth electrical signal and generating audio corresponding to the fourth electrical signal. electronic equipment.

3. In claim 1 or claim 2, A transmitter for the ear and a receiver for the ear, The transmitter for the ear has a function of generating a fifth ultrasonic wave of a fifth frequency and a function of transmitting a fifth electrical signal corresponding to the fifth frequency to the control circuit, the ear receiving unit has a function of receiving a sixth ultrasonic wave of a sixth frequency that is the fifth ultrasonic wave reflected by a blood vessel in the ear of the user, a function of generating a sixth electrical signal according to the sixth frequency, and a function of transmitting the sixth electrical signal to the control circuit; The control circuit has a function of calculating a blood flow velocity in the blood vessel of the ear using the fifth electrical signal and the sixth electrical signal, and a function of transmitting a seventh electrical signal corresponding to the blood flow velocity in the blood vessel of the ear to the display unit for the right eye and the display unit for the left eye. electronic equipment.

4. In any one of claims 1 to 3, A transmitter for the head and a receiver for the head are included, the head transmitter has a function of generating an eighth ultrasonic wave having an eighth frequency and a function of transmitting an eighth electrical signal corresponding to the eighth frequency to the control circuit; the head receiving unit has a function of receiving a ninth ultrasonic wave of a ninth frequency that is the eighth ultrasonic wave reflected by a blood vessel in the user's head, a function of generating a ninth electrical signal according to the ninth frequency, and a function of transmitting the ninth electrical signal to the control circuit; The control circuit has a function of calculating a blood flow velocity of a blood vessel in the head by using the eighth electrical signal and the ninth electrical signal, and a function of transmitting a tenth electrical signal corresponding to the blood flow velocity of the blood vessel in the head to the display unit for the right eye and the display unit for the left eye. electronic equipment.