Indication device

Abstract

Provided is a display apparatus having a high definition and a large diagonal size. The display apparatus has a first layer and a second layer that is located above the first layer. The first layer has a substrate and a plurality of circuit regions, and the second layer has a plurality of display regions. In addition, the substrate is a glass substrate. Each of the plurality of circuit regions has a driving circuit, and the driving circuit has a transistor that includes a low-temperature polysilicon in a channel forming region. Each of the plurality of display regions has a display pixel, and the display pixel has a light-emitting device and a transistor that includes a metal oxide in a channel forming region. The driving circuit included in one of the plurality of circuit regions has a function of driving the display pixel included in one of the plurality of display regions.

Description

[Technical Field] 【0001】 One aspect of the present invention relates to a display device and an electronic device. 【0002】 Furthermore, one aspect of the present invention is not limited to the above-mentioned technical field. The technical field of the invention disclosed herein relates to a product, a driving method, or a manufacturing method. Alternatively, one aspect of the present invention relates to a process, a machine, a manufacture, or a composition of matter. More specifically, examples of the technical field of one aspect of the present invention disclosed herein include semiconductor devices, display devices, liquid crystal display devices, light-emitting devices, energy storage devices, imaging devices, memory devices, signal processing devices, processors, electronic devices, systems, methods for driving them, methods for manufacturing them, or methods for inspecting them. [Background technology] 【0003】 In recent years, various improvements have been made to the display devices used in XR (Extended Reality or Cross Reality) devices such as VR (Virtual Reality) and AR (Augmented Reality), as well as mobile phones such as smartphones, tablet devices, and notebook PCs (Personal Computers). For example, development is progressing on display devices with high pixel density, high color reproduction accuracy (NTSC ratio), smaller drive circuits, and reduced power consumption. 【0004】 To increase the area of ​​the display unit of a display device, one method is to reduce the bezel area surrounding the display unit. Since the bezel area of ​​the display unit of a display device may contain drive circuits, the bezel area can be reduced in size or eliminated by placing the drive circuits in a different area instead of the bezel area. For example, as a configuration to reduce the bezel area, Patent Document 1 discloses a configuration in which the display unit of a display device is divided, and one of the multiple display units and the corresponding drive circuit are superimposed. [Prior art documents] 【Patent Document】 【0005】 【Patent Document 1】 International Publication No. 2021 / 191721 【Summary of the Invention】 【Problems to be Solved by the Invention】 【0006】 As described above, in a display device in which a display unit is divided, the driving circuit corresponding to one display area may be arranged so as to overlap the display area in a plan view. In this case, the display device can be manufactured, for example, by providing the driving circuit on a semiconductor substrate and providing display pixels above the driving circuit. 【0007】 By the way, the diagonal size of such a display device is limited by the size of the semiconductor substrate. When a wafer made of silicon (hereinafter referred to as a silicon wafer) is used as the semiconductor substrate, as an example, in order to manufacture a display device with a diagonal size exceeding 20 inches, a silicon wafer with a diameter exceeding 20 inches is required. Since the diameter of the silicon wafers currently used in semiconductor manufacturing lines is generally up to 300 mm (approximately 12 inches), it can be said that it is difficult to prepare a silicon wafer with a diameter exceeding 300 mm. 【0008】 One aspect of the present invention is to provide a display device with high definition and a large diagonal size as one of the problems. Or, one aspect of the present invention is to provide an electronic device having the above display device as one of the problems. Or, one aspect of the present invention is to provide a novel display device or a novel electronic device as one of the problems. 【0009】 The problems of one aspect of the present invention are not limited to the problems listed above. The problems listed above do not prevent the existence of other problems. Other problems are those not mentioned in this item as described below. Problems not mentioned in this item can be derived by those skilled in the art from the descriptions in the specification, drawings, etc., and can be appropriately extracted from these descriptions. One aspect of the present invention solves at least one of the problems listed above and other problems. One aspect of the present invention does not necessarily need to solve all of the problems listed above and other problems. 【Means for Solving the Problems】 【0010】 (1) One aspect of the present invention is a display device having a first layer and a second layer located above the first layer. The first layer has a substrate and a plurality of circuit regions, and the second layer has a plurality of display regions. Each of the plurality of circuit regions has a drive circuit, and the drive circuit has a transistor including low-temperature polysilicon in a channel formation region. Each of the plurality of display regions has a display pixel, and the display pixel has a transistor including a metal oxide in a channel formation region and a light-emitting device. The drive circuit included in one of the plurality of circuit regions has a function of driving the display pixel included in one of the plurality of display regions. Thereby, the display device can display images at mutually different frame frequencies in at least two of the plurality of display regions. 【0011】 (2) Alternatively, in the above (1), one of the plurality of circuit regions and one of the plurality of display regions may be configured to be located in overlapping regions in a top view. 【0012】 (3) Alternatively, in the above (1) or (2), wirings may extend in a direction perpendicular to the substrate between the first layer and the second layer. In particular, it is preferable that the wirings are electrically connected to the display pixels and the drive circuits. 【0013】 (4) Alternatively, in one aspect of the present invention, the substrate may be a glass substrate in any one of the above (1) to (3). 【0014】 (5) Alternatively, one aspect of the present invention is an electronic device having any one of the above-mentioned (1) to (4) display devices and a housing. [Effects of the Invention] 【0015】 According to one aspect of the present invention, a display device with high resolution and a large diagonal size can be provided. Alternatively, according to one aspect of the present invention, an electronic device having the above-mentioned display device can be provided. Alternatively, according to one aspect of the present invention, a novel display device or a novel electronic device can be provided. 【0016】 The effects of one aspect of the present invention are not limited to those listed above. The effects listed above do not preclude the existence of other effects. These other effects are those described below and not mentioned in this section. Those not mentioned in this section can be derived from the description in the specification or drawings, etc., by those skilled in the art, and can be appropriately extracted from these descriptions. One aspect of the present invention has at least one of the effects listed above and other effects. Therefore, one aspect of the present invention may, in some cases, not have the effects listed above. [Brief explanation of the drawing] 【0017】 Figures 1A and 1B are schematic cross-sectional diagrams showing examples of the configuration of a display device. Figure 2A is a schematic plan view showing an example of the display unit of a display device, and Figure 2B is a schematic plan view showing an example of the drive circuit area of ​​a display device. Figure 3 is a block diagram showing an example of the configuration of a display device. Figures 4A and 4B are schematic top views showing examples of the configuration of a display device. Figure 5 is a block diagram showing an example of a display device configuration. Figure 6 is a schematic cross-sectional view showing an example of the configuration of a display device. Figures 7A and 7B are cross-sectional views showing an example of a transistor. Figures 7C through 7E are cross-sectional views showing an example of a display device. Figure 8 is a schematic cross-sectional view showing an example of the configuration of a display device. Figure 9 is a schematic cross-sectional view showing an example of the configuration of a display device. Figure 10 is a schematic cross-sectional view showing an example of the configuration of a display device. Figures 11A to 11F show examples of the configuration of a light-emitting device. Figures 12A to 12C show examples of the configuration of a light-emitting device. Figure 13A is a circuit diagram showing an example of the configuration of a pixel circuit included in a display device, and Figure 13B is a schematic perspective view showing an example of the configuration of a pixel circuit included in a display device. Figures 14A to 14D are circuit diagrams showing examples of the configuration of pixel circuits included in a display device. Figures 15A to 15D are circuit diagrams showing examples of the configuration of pixel circuits included in a display device. Figures 16A to 16G are plan views showing an example of a pixel. Figures 17A to 17F are plan views showing an example of a pixel. Figures 18A to 18H are plan views showing an example of a pixel. Figures 19A to 19D are plan views showing examples of pixels. Figures 20A and 20B show examples of the display module configuration. Figures 21A to 21F show examples of the configuration of electronic equipment. Figures 22A to 22D show examples of electronic device configurations. Figures 23A to 23C show examples of the configuration of electronic equipment. Figures 24A to 24H show examples of the configuration of electronic equipment. [Modes for carrying out the invention] 【0018】 In this specification, a semiconductor device refers to a device that utilizes semiconductor properties, including circuits containing semiconductor elements (e.g., transistors, diodes, and photodiodes), devices having such circuits, etc. It also refers to any device that can function by utilizing semiconductor properties. For example, integrated circuits, chips equipped with integrated circuits, and electronic components with chips housed in packages are all examples of semiconductor devices. Furthermore, for example, memory devices, display devices, light-emitting devices, lighting devices, and electronic devices may be semiconductor devices themselves or may have semiconductor devices. 【0019】 Furthermore, when it is stated in this specification that X and Y are connected, it is assumed that this specification discloses the cases in which X and Y are electrically connected, functionally connected, and directly connected. Therefore, it is assumed that the disclosed connections are not limited to predetermined connections, such as those shown in the figures or text, but also include connections other than those shown in the figures or text. X and Y are objects (e.g., devices, elements, circuits, wiring, electrodes, terminals, conductive films, layers, etc.). 【0020】 One example of a case where X and Y are electrically connected is that one or more elements that enable the electrical connection between X and Y (e.g., switches, transistors, capacitive elements, inductors, resistors, diodes, display devices, light-emitting devices, and loads) can be connected between X and Y. Note that a switch has the function of being controlled to be on or off. In other words, a switch has the function of controlling whether or not current flows by being in a conductive state (on state) or a non-conductive state (off state). 【0021】 One example of a functionally connected X and Y is when one or more circuits that enable the functional connection between X and Y (for example, logic circuits (e.g., inverters, NAND gates, and NOR gates), signal conversion circuits (e.g., digital-to-analog conversion circuits, analog-to-digital conversion circuits, and gamma correction circuits), potential level conversion circuits (e.g., power supply circuits such as boost or buck converters, and level shifter circuits that change the potential level of a signal), voltage sources, current sources, switching circuits, amplification circuits (e.g., circuits that can increase the signal amplitude or current, operational amplifiers, differential amplifiers, source follower circuits, and buffer circuits), signal generation circuits, memory circuits, and control circuits) can be connected between X and Y. Note that, as an example, even if another circuit is placed between X and Y, if a signal output from X is transmitted to Y, X and Y are considered to be functionally connected. 【0022】 Furthermore, when it is explicitly stated that X and Y are electrically connected, this includes both cases where X and Y are electrically connected (i.e., connected with another element or circuit in between) and cases where X and Y are directly connected (i.e., connected without another element or circuit in between). 【0023】 Furthermore, this specification deals with circuit configurations in which multiple elements are electrically connected to wiring (wiring that supplies a constant potential or wiring that transmits a signal). For example, if X and wiring are directly connected, and Y and the wiring are directly connected, this specification may state that X and Y are directly electrically connected. 【0024】 Furthermore, for example, it can be expressed as, "X, Y, the source (which may be rephrased as either the first or second terminal) and the drain (which may be rephrased as either the first or second terminal) of the transistor are electrically connected to each other, and are electrically connected in the order of X, transistor source, transistor drain, and Y." Or, "The source of the transistor is electrically connected to X, and the drain of the transistor is electrically connected to Y, and X, transistor source, transistor drain, and Y are electrically connected in this order." Or, "X is electrically connected to Y via the source and drain of the transistor, and X, transistor source, transistor drain, and Y are provided in this connection order." By specifying the order of connections in the circuit configuration using similar methods of expression as these examples, the source and drain of the transistor can be distinguished and their technical scope can be determined. Note that these methods of expression are examples and are not limited to these methods of expression. Here, X and Y are objects (for example, devices, elements, circuits, wiring, electrodes, terminals, conductive films, or layers). 【0025】 Even if independent components are shown as electrically connected in a circuit diagram, a single component may possess the functions of multiple components. For example, if part of a wire also functions as an electrode, a single conductive film possesses the functions of both a wire and an electrode. Therefore, in this specification, "electrically connected" includes cases where a single conductive film possesses the functions of multiple components. 【0026】 Furthermore, in this specification, "resistive element" can refer to, for example, a circuit element having a resistance value higher than 0Ω, or wiring having a resistance value higher than 0Ω. Therefore, in this specification, "resistive element" includes wiring having a resistance value, a transistor, diode, or coil through which current flows between the source and drain. Therefore, the term "resistive element" may be replaced with terms such as "resistance," "load," or "region having a resistance value." Conversely, terms such as "resistance," "load," or "region having a resistance value" may be replaced with the term "resistive element." The resistance value can be, for example, preferably 1mΩ or more and 10Ω or less, more preferably 5mΩ or more and 5Ω or less, and even more preferably 10mΩ or more and 1Ω or less. Also, for example, 1Ω or more and 1 × 10 9 It may also be less than or equal to Ω. 【0027】 Furthermore, in this specification, "capacitive element" can refer to, for example, a circuit element having a capacitance value higher than 0F, a region of wiring having a capacitance value higher than 0F, parasitic capacitance, or the gate capacitance of a transistor. Also, 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 terms such as "capacitive element," "parasitic capacitance," or "gate capacitance." In addition, a "capacitance" (including "capacitances" with three or more terminals) has a configuration that includes an insulator and a pair of conductors sandwiching the insulator. Therefore, the term "pair of conductors" in "capacitance" can be replaced with "pair of electrodes," "pair of conductive regions," "pair of regions," or "pair of terminals." Also, the terms "one of the pair of terminals" or "the other of the pair of terminals" may be referred to as the first terminal or the second terminal, respectively. The capacitance value can be, for example, 0.05fF or more and 10pF or less. Alternatively, it may be, for example, 1pF or more and 10μF or less. 【0028】 Furthermore, in this specification, a transistor has three terminals called the gate, source, and drain. The gate is a control terminal that controls the conduction state of the transistor. The two terminals that function as either the source or the drain are the input and output terminals of the transistor. Depending on the conductivity type of the transistor (n-channel or p-channel) and the potential applied to the three terminals of the transistor, one of the two input and output terminals becomes the source and the other becomes the drain. For this reason, in this specification, the terms source and drain may be interchangeable. Also, in this specification, when describing the connection relationships of a transistor, the notation "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) is used. Depending on the structure of the transistor, in addition to the three terminals described above, there may be a back gate. In this case, in this specification, one of the gate or back gate of the transistor may be called the first gate, and the other of the gate or back gate of the transistor may be called the second gate. Furthermore, in the same transistor, the terms "gate" and "back gate" may be interchangeable. Furthermore, if a transistor has three or more gates, in this specification, each gate may be referred to as the first gate, second gate, third gate, and so on. 【0029】 For example, in this specification, a transistor with a multi-gate structure having 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-current and improve the transistor's breakdown voltage (improve reliability). Alternatively, the multi-gate structure allows for a voltage-current characteristic with a flat slope, where the current between the drain and source does not change much even when the voltage between the drain and source changes during operation in the saturation region. By utilizing this flat voltage-current characteristic, an ideal current source circuit or an active load with a very high resistance can be realized. As a result, a differential circuit or current mirror circuit with good characteristics can be realized. 【0030】 Furthermore, in this specification, circuit elements such as "light-emitting devices" and "light-receiving devices" may have polarities called "anode" and "cathode." In the case of a "light-emitting device," it may be possible to make the "light-emitting device" emit light by applying a forward bias (applying a positive potential relative to the "cathode" to the "anode"). In the case of a "light-receiving device," it may be possible to generate a current between the "anode" and "cathode" by applying a zero bias or reverse bias (applying a negative potential relative to the "cathode" to the "anode") and irradiating the "light-receiving device" with light. As described above, the "anode" and "cathode" may be treated as input / output terminals in circuit elements such as "light-emitting devices" and "light-receiving devices." In this specification, the "anode" and "cathode" in circuit elements such as "light-emitting devices" and "light-receiving devices" may be referred to as terminals (first terminal, second terminal, etc.). For example, one of the "anode" or "cathode" may be referred to as the first terminal, and the other as the second terminal. 【0031】 Furthermore, even if a single circuit element is depicted in a circuit diagram, that element may actually comprise multiple circuit elements. For example, if one resistor is shown in a circuit diagram, it includes cases where two or more resistors are electrically connected in series. Similarly, if one capacitor is shown in a circuit diagram, it includes cases where two or more capacitors are electrically connected in parallel. Similarly, if one transistor is shown in a circuit diagram, it includes cases where two or more transistors are electrically connected in series and the gates of each transistor are electrically connected to each other. Likewise, if one switch is shown in a circuit diagram, it includes cases where the switch has two or more transistors, and these two or more transistors are electrically connected in series or parallel, and the gates of each transistor are electrically connected to each other. 【0032】 Furthermore, in this specification, the term "node" can be replaced with "terminal," "wiring," "electrode," "conductive layer," "conductor," or "impurity region," depending on the circuit configuration and device structure. Also, a terminal or wiring can be replaced with "node." 【0033】 Furthermore, in this specification, "voltage" and "potential" may be used interchangeably as appropriate. "Voltage" is the potential difference from a reference potential. For example, if the reference potential is the ground potential (earth potential), then "voltage" can be replaced with "potential." Note that the ground potential does not necessarily mean 0V. Also, potential is relative, and as the reference potential changes, the potential applied to the wiring, the potential applied to the circuit, and the potential output from the circuit also change. 【0034】 Furthermore, in this specification, the terms "high-level potential" and "low-level potential" do not refer to specific potentials. For example, if two wires are both described as "functioning as wires that supply a high-level potential," the high-level potentials provided by each wire do not have to be equal. Similarly, if two wires are both described as "functioning as wires that supply a low-level potential," the low-level potentials provided by each wire do not have to be equal. 【0035】 Furthermore, "electric current" refers to the phenomenon of electric charge movement (electrical conduction). For example, the statement "electrical conduction of positively charged elements is occurring" can be rephrased as "electrical conduction of negatively charged elements is occurring in the opposite direction." Therefore, in this specification, unless otherwise specified, "electric current" refers to the phenomenon of electric charge movement associated with the movement of carriers (electrical conduction). Examples of carriers include electrons, holes, anions, cations, or complex ions, and the carriers differ depending on the system through which the current flows (e.g., semiconductors, metals, electrolytes, or vacuum). In addition, the "direction of current" in wiring, etc., is the direction in which positively charged carriers move and is expressed as a positive current quantity. In other words, the direction in which negatively charged carriers move is the opposite direction to the direction of the current and is expressed as a negative current quantity. Therefore, in this specification, if there is no specification regarding the positive or negative (or direction) of the 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." 【0036】 Furthermore, in this specification, ordinal numbers such as "first," "second," and "third" are used to avoid confusion of constituent elements. Therefore, they do not limit the number of constituent elements, nor do they limit the order of the constituent elements. For example, a constituent element referred to as "first" in one embodiment of this specification may be referred to as "second" in another embodiment or in the claims. Also, for example, a constituent element referred to as "first" in one embodiment of this specification may be omitted in another embodiment or in the claims. 【0037】 Furthermore, in this specification, terms indicating placement such as "above" and "below" are sometimes used for convenience to explain the positional relationship between components with reference to the drawings. Also, the positional relationship between components changes as appropriate depending on the direction in which each component is depicted. Therefore, the terms explained in the specification are not limited to those described and can be appropriately rephrased depending on the situation. For example, the expression "insulator located on the upper surface of the conductor" can be rephrased as "insulator located on the lower surface of the conductor" by rotating the orientation of the drawing shown by 180 degrees. 【0038】 Furthermore, the terms "above" and "below" do not limit the positional relationship of the components to being directly above or directly below and in direct contact. For example, the expression "electrode B on insulating layer A" does not require that electrode B be formed in direct contact with insulating layer A, and does not exclude cases where other components are included between insulating layer A and electrode B. Similarly, for example, the expression "electrode B above insulating layer A" does not require that electrode B be formed in direct contact with insulating layer A, and does not exclude cases where other components are included between insulating layer A and electrode B. Similarly, for example, the expression "electrode B below insulating layer A" does not require that electrode B be formed in direct contact with insulating layer A, and does not exclude cases where other components are included between insulating layer A and electrode B. 【0039】 Furthermore, in this specification, terms such as "rows" and "columns" may be used to describe matrix-like arrangements of components and their positional relationships. The positional relationships between components change as appropriate depending on the direction in which each component is depicted. Therefore, the terminology used is not limited to that described in the specification and can be appropriately rephrased depending on the situation. For example, the expression "row direction" can sometimes be rephrased as "column direction" by rotating the orientation of the drawing shown by 90 degrees. 【0040】 Furthermore, in this specification, the terms "film" and "layer" can be interchanged as needed. 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." Alternatively, depending on the circumstances, the terms "film" and "layer" can be omitted and 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." 【0041】 Furthermore, in this specification, the terms "electrode," "wiring," and "terminal" do not functionally limit these components. For example, "electrode" may be used as part of "wiring," and vice versa. Moreover, the terms "electrode" or "wiring" include cases where multiple "electrodes" or "wiring" are formed as a single unit. Similarly, for example, "terminal" may be used as part of "wiring" or "electrode," and vice versa. Furthermore, the term "terminal" also includes cases where multiple "electrodes," "wiring," or "terminals" are formed as a single unit. Therefore, for example, an "electrode" can be part of "wiring" or a "terminal," and for example, a "terminal" can be part of "wiring" or an "electrode." In addition, the terms "electrode," "wiring," or "terminal" may be replaced with the term "region" in some cases. 【0042】 Furthermore, in this specification, terms such as "wiring," "signal line," and "power line" can be interchanged depending on the circumstances or situation. For example, the term "wiring" may be changed to the term "signal line." Similarly, the term "wiring" may be changed to the term "power line." The same applies in reverse, where terms such as "signal line" or "power line" can be changed to the term "wiring." The term "power line" may be changed to the term "signal line." Similarly, the same applies in reverse, where terms such as "signal line" may be changed to the term "power line." Furthermore, the term "potential" applied to the wiring may be changed to the term "signal" depending on the circumstances or situation. Similarly, the term "signal" may be changed to the term "potential." 【0043】 In this specification, "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 called oxide semiconductors or simply OS), etc. For example, if a metal oxide is included in the channel formation region of a transistor, that metal oxide may be referred to as an oxide semiconductor. In other words, if a metal oxide can constitute the channel formation region of a transistor having at least one of amplification, rectification, and switching functions, that metal oxide can be referred to as a metal oxide semiconductor. Furthermore, when an OS transistor is described, it can be rephrased as a transistor having a metal oxide or oxide semiconductor. 【0044】 Furthermore, in this specification, metal oxides containing nitrogen may also be collectively referred to as metal oxides. Alternatively, metal oxides containing nitrogen may be called metal oxynitrides. 【0045】 Furthermore, in this specification, semiconductor impurities refer to elements other than the main components constituting the semiconductor layer. For example, elements with a concentration of less than 0.1 atomic percent are impurities. The presence of impurities can cause one or more of the following: an increase in the defect level density of the semiconductor, a decrease in carrier mobility, or a decrease in crystallinity. When the semiconductor is an oxide semiconductor, impurities that alter the properties of the semiconductor 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 components, particularly hydrogen (also found in water), lithium, sodium, silicon, boron, phosphorus, carbon, and nitrogen. When the semiconductor is a silicon layer, impurities that alter the properties of the semiconductor include, for example, Group 1 elements, Group 2 elements, Group 13 elements, and Group 15 elements (excluding oxygen and hydrogen). 【0046】 In this specification, a switch refers to a device that has the function of controlling whether or not to allow current to flow by being in a conductive (on) state or a non-conductive (off) state. Alternatively, a switch refers to a device that has the function of selecting and switching the path through which current flows. Therefore, a switch may have two or more terminals for conducting current in addition to control terminals. Examples include electrical switches and mechanical switches. In other words, a switch is not limited to any particular type, as long as it can control current. 【0047】 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, and diode-connected transistors), or logic circuits combining these. When a transistor is used as a switch, the "conducting state" of the transistor refers to a state where, for example, the source and drain electrodes of the transistor can be considered electrically short-circuited, or a state where current can flow between the source and drain electrodes. Conversely, the "non-conducting state" of the transistor refers to a state where the source and drain electrodes of the transistor can be considered electrically disconnected. When a transistor is used simply as a switch, the polarity (conductivity type) of the transistor is not particularly limited. 【0048】 One example of a mechanical switch is a switch using MEMS (Micro-Electro-Mechanical Systems) technology. This switch has mechanically movable electrodes, and it operates by controlling the conduction and non-conductivity through the movement of these electrodes. 【0049】 Furthermore, in this specification, devices fabricated with a metal mask or FMM (Fine Metal Mask, high-resolution metal mask) may be referred to as MM (metal mask) structured devices. Also, in this specification, devices fabricated without using a metal mask or FMM may be referred to as MML (metal maskless) structured devices. 【0050】 In this specification, a structure in which different light-emitting layers are created or painted for each color of light-emitting device (here, blue (B), green (G), and red (R)) may be referred to as an SBS (Side By Side) structure. Also, in this specification, a light-emitting device capable of emitting white light may be referred to as a white light-emitting device. A white light-emitting device can be combined with a colored layer (for example, a color filter) to create a full-color display device. 【0051】 Furthermore, light-emitting devices can be broadly classified into single structures and tandem structures. A single-structure device has one light-emitting unit between a pair of electrodes, and it is preferable that the light-emitting unit includes one or more light-emitting layers. When obtaining white light emission using two light-emitting layers, the light-emitting layers should be selected such that the light-emitting colors of each layer are complementary. For example, by making the light-emitting color of the first light-emitting layer and the light-emitting color of the second light-emitting layer complementary, a configuration that emits white light as a whole can be obtained. Also, when obtaining white light emission using three or more light-emitting layers, the light-emitting device should be configured so that the light-emitting colors of the three or more layers combine to emit white light as a whole. 【0052】 A tandem 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, the device should be configured such that the light from the light-emitting layers of the multiple light-emitting units is combined to produce white light emission. The configuration for obtaining white light emission is the same as that for a single-structure device. In a tandem device, it is preferable to provide an intermediate layer, such as a charge-generating layer, between the multiple light-emitting units. 【0053】 Furthermore, when comparing the aforementioned white light-emitting devices (single or tandem structure) with SBS structure light-emitting devices, SBS structure light-emitting devices can consume less power than white light-emitting devices. If you want to keep power consumption low, it is preferable to use SBS structure light-emitting devices. On the other hand, white light-emitting devices are preferable because their manufacturing process is simpler than that of SBS structure light-emitting devices, which can lead to lower manufacturing costs or higher manufacturing yields. 【0054】 In this specification, "parallel" means a state in which two lines are positioned at an angle of -10° or more and 10° or less. Therefore, the case of -5° or more and 5° or less is also included. Furthermore, "approximately parallel" or "roughly parallel" means a state in which two lines are positioned at an angle of -30° or more and 30° or less. Furthermore, "perpendicular" means a state in which two lines are positioned at an angle of 80° or more and 100° or less. Therefore, the case of 85° or more and 95° or less is also included. Furthermore, "approximately perpendicular" or "roughly perpendicular" means a state in which two lines are positioned at an angle of 60° or more and 120° or less. 【0055】 Furthermore, in this specification, 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. Also, if multiple configuration examples are shown within one embodiment, these configuration examples can be appropriately combined with each other. 【0056】 Furthermore, any content described in one embodiment (even partial content) may be applied to, combined with, or substituted for at least one of the contents described in another embodiment (even partial content) and one or more other embodiments (even partial content). 【0057】 The content described in the embodiments refers to the content described using various figures or the content described using text in the specification in each embodiment. 【0058】 Furthermore, a diagram (even a part of it) described in one embodiment can be combined with another part of that diagram, another diagram (even a part of it) described in the same embodiment, and at least one diagram (even a part of it) described in one or more other embodiments to form even more diagrams. 【0059】 The embodiments described herein are explained with reference to the drawings. However, it will be readily apparent to those skilled in the art that the embodiments can be implemented in many different ways, and their form and details can be modified in various ways without departing from the spirit and scope thereof. Therefore, the present invention is not to be interpreted as being limited to the contents described in the embodiments. In the configuration of the invention in the embodiments, the same reference numerals are used in common across different drawings for the same parts or parts having similar functions, and repeated explanations may be omitted. Also, in perspective views and the like, some components may be omitted in order to ensure clarity of the drawings. 【0060】 Furthermore, in the drawings of this specification, plan views may be used to explain the configuration of each embodiment. A plan view is, for example, a diagram showing a surface of the configuration viewed from a direction perpendicular to the horizontal plane, or a surface (cross-section) of the configuration cut horizontally (either direction of viewing may be called a plan view). In addition, hidden lines (e.g., dashed lines) can be included in the plan view to show the positional relationship of multiple elements included in the configuration, or the relationship of overlap of such multiple elements. In this specification, the term "plan view" may be replaced with the terms "projection view," "top view," or "bottom view." Also, depending on the situation, a surface (cross-section) of the configuration cut in a direction other than the horizontal direction may be called a plan view. 【0061】 Furthermore, in the drawings of this specification, cross-sectional views may be used to explain the configuration of each embodiment. A cross-sectional view is, for example, a diagram showing a view of a configuration from a direction perpendicular to the horizontal plane, or a diagram showing a view of a configuration cut in a direction perpendicular to the horizontal plane (either direction of view may be called a cross-sectional view). In this specification, the term "cross-sectional view" may be replaced with the terms "front view" or "side view." Also, depending on the situation, a cross-sectional view may refer to a view of a configuration cut in a direction other than the vertical direction, rather than a view of a vertical cut. 【0062】 In this specification, when the same reference numeral is used for multiple elements, and especially when it is necessary to distinguish them, the reference numeral may be accompanied by an identifying numeral such as "_1", "[n]", or "[m,n]". In addition, in drawings, etc., when an identifying numeral such as "_1", "[n]", or "[m,n]" is accompanied by a reference numeral, the identifying numeral may be omitted in this specification if it is not necessary to distinguish them. 【0063】 Furthermore, in the drawings of this specification, the size, layer thickness, or area may be exaggerated for clarity. Therefore, it is not necessarily limited to that scale. The drawings are schematic representations of ideal examples and are not limited to the shapes or values ​​shown in the drawings. For example, they may include variations in signals, voltages, or currents due to noise, or variations in signals, voltages, or currents due to timing differences. 【0064】 (Embodiment 1) In this embodiment, a display device according to one aspect of the present invention will be described. 【0065】 <Example of display device configuration> Figure 1A is a schematic cross-sectional view of a display device according to one embodiment of the present invention. The display device DSP shown in Figure 1A includes, as an example, a pixel layer PXAL and a circuit layer SICL. 【0066】 The pixel layer PXAL is located on the circuit layer SICL. The pixel layer PXAL is superimposed on the region containing the drive circuit region DRV, which will be described later. 【0067】 The circuit layer SICL comprises a substrate BS and a drive circuit region DRV. 【0068】 For the substrate BS, for example, glass substrates, quartz substrates, plastic substrates, sapphire glass substrates, metal substrates, stainless steel substrates, substrates with stainless steel foil, tungsten substrates, substrates with tungsten foil, flexible substrates, laminated films, paper containing fibrous materials, or base film can be used. Examples of glass substrates include barium borosilicate glass, aluminoborosilicate glass, or soda-lime glass. Examples of flexible substrates, laminated films, and base film include plastics such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), or polytetrafluoroethylene (PTFE). Alternatively, another example is synthetic resins such as acrylic resin. Another example is polypropylene, polyester, polyvinyl fluoride, or polyvinyl chloride. Alternatively, one example is polyamide, polyimide, aramid, epoxy resin, inorganic vapor-deposited film, or paper. Furthermore, if the manufacturing process of the display device DSP includes heat treatment, it is preferable to select a material with high heat resistance for the substrate BS. 【0069】 In this embodiment, the substrate BS is described as a substrate made of a material with high heat resistance, such as a glass substrate. 【0070】 The drive circuit area (DRV) is located on the circuit board (BS). 【0071】 The drive circuit region (DRV) includes, for example, a drive circuit for driving pixels included in the pixel layer (PXAL), which will be described later. A specific example of the configuration of the drive circuit region (DRV) will be described later. 【0072】 The pixel layer (PXAL) may, for example, have multiple pixels. Furthermore, the multiple pixels may be arranged in a matrix within the pixel layer (PXAL). 【0073】 Furthermore, each of the multiple pixels can represent one or more colors. In particular, the multiple colors can be, for example, three colors: red (R), green (G), and blue (B). Alternatively, the multiple colors can be, for example, red (R), green (G), and blue (B), plus one or more colors selected from cyan (C), magenta (M), yellow (Y), and white (W). Note that each pixel that represents a different color is called a subpixel, and when white is represented by multiple subpixels of different colors, those multiple subpixels are sometimes collectively called a pixel. Also, in this specification, for convenience, subpixels may be referred to as pixels in the explanation. 【0074】 Figure 2A is an example of a top view of a display device DSP, showing only the display unit DIS. Note that the display unit DIS can be a top view of the pixel layer PXAL. 【0075】 Furthermore, in the display device DSP shown in Figure 2A, the display unit DIS is divided into, for example, an area of ​​m rows and n columns (where m is an integer greater than or equal to 1, and n is an integer greater than or equal to 1). Therefore, the display unit DIS has a configuration having display areas ARA[1,1] to ARA[m,n]. In Figure 2A, as an example, we show excerpts of each of the following display areas: ARA[1,1], ARA[2,1], ARA[m-1,1], ARA[m,1], ARA[1,2], ARA[2,2], ARA[m-1,2], ARA[m,2], ARA[1,n-1], ARA[2,n-1], ARA[m-1,n-1], ARA[m,n-1], ARA[1,n], ARA[2,n], ARA[m-1,n], and ARA[m,n]. 【0076】 For example, if you want to divide the display unit DIS into 32 regions, you can set m=4 and n=8 and apply it to Figure 2A. Incidentally, if the screen resolution of the display device DSP is 8K4K, the number of pixels will be 7680 × 4320 pixels. Also, if the sub-pixels of the display unit DIS are red (R), green (G), and blue (B), the total number of sub-pixels will be 7680 × 4320 × 3. Here, if the pixel array of the display unit DIS with a screen resolution of 8K4K is divided into 32 regions, the number of pixels per region will be 960 × 1080 pixels, and if the sub-pixels of that display device DSP are red (R), green (G), and blue (B), the number of sub-pixels per region will be 960 × 1080 × 3. 【0077】 Here, we consider the drive circuit region DRV included in the circuit layer SICL when the display unit DIS in the display device DSP of Figure 2A is divided into an area of ​​m rows and n columns. 【0078】 Figure 2B is an example of a plan view of a display device DSP, showing only the drive circuit region (DRV) included in the circuit layer SICL. 【0079】 In the DSP display device shown in Figure 2A, the display unit DIS is divided into m x n regions, so each of the divided display regions ARA[1,1] to ARA[m,n] requires a corresponding drive circuit. Specifically, the drive circuit region DRV can also be divided into m x n regions, and a drive circuit can be provided in each of the divided regions. 【0080】 Figure 2B shows a configuration in which the DSP display device is divided into an m x n region. Therefore, the DRV has circuit regions ARD[1,1] through ARD[m,n]. In Figure 2B, as an example, the following regions are shown as excerpts: ARD[1,1], ARD[2,1], ARD[m-1,1], ARD[m,1], ARD[1,2], ARD[2,2], ARD[m-1,2], ARD[m,2], ARD[1,n-1], ARD[2,n-1], ARD[m-1,n-1], ARD[m,n-1], ARD[1,n], ARD[2,n], ARD[m-1,n], and ARD[m,n]. 【0081】 Each of the circuit regions ARD[1,1] to ARD[m,n] has a drive circuit SD and a drive circuit GD. For example, the drive circuit SD and drive circuit GD contained in the circuit region ARD[i,j] (not shown in Figure 2B) located at the i-th row and j-th column (where i is an integer between 1 and m, and j is an integer between 1 and n) can drive multiple pixels contained in the display region ARA[i,j] (not shown in Figure 2A) located at the i-th row and j-th column of the display unit DIS. 【0082】 The drive circuit SD functions, for example, as a source driver circuit that transmits image signals to multiple pixels included in the corresponding circuit region ARD. The drive circuit SD may also include a digital-to-analog conversion circuit that converts digital image signals into analog data. 【0083】 The drive circuit GD functions, for example, as a gate driver circuit for selecting multiple pixels to which an image signal will be transmitted in the corresponding circuit region ARD. 【0084】 Furthermore, as can be seen from Figures 2A and 2B, the display area ARA[i,j] and the circuit area ARD[i,j] are located in overlapping regions in a plan view. Because the display area ARA[i,j] and the circuit area ARD[i,j] overlap, the wiring electrically connecting the display area ARA[i,j] and the circuit area ARD[i,j] can be shortened, thereby reducing the parasitic resistance of the wiring. Also, by shortening the wiring, the parasitic capacitance present in the wiring can be reduced, thereby reducing the time constant in the wiring. By reducing the time constant in the wiring, the time required to write the image to the display area ARA[i,j] can be shortened, and as a result, the frame frequency can be increased. 【0085】 Figure 3 is a perspective view of the display device DSP shown in Figures 2A and 2B. Figure 3 also shows selected display areas ARA[1,1], ARA[m,1], ARA[1,n], and ARA[m,n] as display area ARA, and selected circuit areas ARD[1,1], ARD[m,1], ARD[1,n], and ARD[m,n] as circuit area ARD. 【0086】 In the display device DSP shown in Figure 3, each of the multiple display areas ARA has, for example, multiple pixels PX. Furthermore, within the display area ARA, the multiple pixels PX are arranged in a matrix. 【0087】 Each of the multiple display areas ARA has multiple wirings GL extending in the row direction and multiple wirings SL extending in the column direction. 【0088】 Each of the multiple pixels PX arranged in a matrix within the display area ARA is electrically connected to the wiring GL of the corresponding row. Similarly, each of the multiple pixels PX is electrically connected to the wiring SL of the corresponding column. 【0089】 Furthermore, in the display device DSP of Figure 3, each of the multiple circuit regions ARD has a drive circuit SD and a drive circuit GD, as shown in the display device DSP of Figure 2B. 【0090】 As explained in Figures 2A and 2B, the drive circuits SD and GD included in the circuit region ARD[i,j] have the function of driving multiple pixels included in the display region ARA[i,j]. For this reason, the drive circuit SD included in the circuit region ARD[i,j] is electrically connected to multiple wirings SL that extend into the display region ARA[i,j]. In addition, the drive circuit GD included in the circuit region ARD[i,j] is electrically connected to multiple wirings GL that extend into the display region ARA[i,j]. 【0091】 Furthermore, in order to electrically connect the display area ARA[i,j] and the circuit area ARD[i,j], multiple wirings SL and multiple wirings GL are provided between the display unit DIS and the drive circuit area DRV. 【0092】 Furthermore, by arranging the display area ARA[i,j] and the circuit area ARD[i,j] to overlap, the wiring that electrically connects the display area ARA[i,j] and the circuit area ARD[i,j] can be extended, for example, in a direction perpendicular to or approximately perpendicular to the substrate BS. By extending the wiring in a direction perpendicular or approximately perpendicular, the length of the wiring can be shortened, and as described above, the parasitic resistance related to the wiring can be reduced. In addition, the parasitic capacitance related to the wiring can be reduced. As a result, the voltage required to supply current to the wiring can be kept low, and power consumption can be reduced. 【0093】 In addition, the display device DSP shown in Figures 1A, 2A, 2B, and 3 has a configuration in which the display area ARA[i,j] and the circuit area ARD[i,j] of the display unit DIS overlap each other, but the display device according to one aspect of the present invention is not limited to this. The configuration of the display device according to one aspect of the present invention does not necessarily have to be such that the display area ARA[i,j] and the circuit area ARD[i,j] overlap each other. 【0094】 For example, as shown in Figure 1B, the display device DSP may be configured such that not only the drive circuit area DRV but also the LIA area is provided on the substrate BS. 【0095】 For example, wiring is provided in the LIA region. In this case, the DSP display device may be configured such that the circuits included in the drive circuit region DRV and the circuits included in the pixel layer PXAL are electrically connected by the wiring included in the LIA region. 【0096】 Figure 4A is an example of a plan view of the display device DSP shown in Figure 1B, showing the drive circuit area DRV (shown by a solid line) and the display unit DIS (shown by a dotted line). In addition, the display device DSP in Figure 4A shows, as an example, a configuration in which the drive circuit area DRV is surrounded by the LIA (Figure 4B shows an example of a plan view of a display device DSP showing only the circuit layer SICL). Therefore, as shown in Figure 4A, the drive circuit area DRV is arranged to overlap the inside of the display unit DIS in a plan view. 【0097】 Furthermore, the display device DSP shown in Figure 4A is assumed to have a display unit DIS divided into display areas ARA[1,1] to ARA[m,n], similar to Figure 2A, and the drive circuit area DRV is also assumed to be divided into circuit areas ARD[1,1] to ARD[m,n]. 【0098】 As shown in Figure 4A, as an example, the correspondence between the display area ARA and the circuit area ARD, which includes the drive circuits that drive the pixels contained in the display area ARA, is illustrated with thick arrows. Specifically, the drive circuits contained in circuit area ARD[1,1] drive the pixels contained in display area ARA[1,1], and the drive circuits contained in circuit area ARD[2,1] drive the pixels contained in display area ARA[2,1]. Furthermore, the drive circuits contained in circuit area ARD[m-1,1] drive the pixels contained in display area ARA[m-1,1], and the drive circuits contained in circuit area ARD[m,1] drive the pixels contained in display area ARA[m,1]. In addition, the drive circuits contained in circuit area ARD[1,n] drive the pixels contained in display area ARA[1,n], and the drive circuits contained in circuit area ARD[2,n] drive the pixels contained in display area ARA[2,n]. Furthermore, the drive circuits contained in circuit region ARD[m-1,n] drive the pixels contained in display region ARA[m-1,n], and the drive circuits contained in circuit region ARD[m,n] drive the pixels contained in display region ARA[m,n]. In other words, although not shown in Figure 4A, the drive circuits contained in circuit region ARD[i,j] located in row i and column j drive the pixels contained in display region ARA[i,j]. 【0099】 In Figure 1B, by electrically connecting the drive circuit contained in the circuit region ARD within the circuit layer SICL and the pixels contained in the display region ARA within the pixel layer PXAL via wiring, the configuration of the display device DSP can be such that the display region ARA[i,j] and the circuit region ARD[i,j] do not necessarily overlap each other. Therefore, the positional relationship between the drive circuit region DRV and the display unit DIS is not limited to the plan view of the display device DSP shown in Figure 4A, and the arrangement of the drive circuit region DRV can be freely determined. 【0100】 In Figures 2B and 4A, the drive circuit SD and drive circuit GD are arranged in a cross shape within each of the circuit regions ARD[1,1] to ARD[m,n]. However, the arrangement of the drive circuit SD and drive circuit GD is not limited to the configuration of the display device according to one embodiment of the present invention. For example, the arrangement of the drive circuit SD and drive circuit GD may be L-shaped within one circuit region ARD of the drive circuit region DRV, as shown in Figure 3. Alternatively, one of the drive circuit SD and drive circuit GD may be arranged vertically in a plan view, and the other of the drive circuit SD and drive circuit GD may be arranged horizontally in a plan view. 【0101】 As shown in Figures 2A to 4B, by dividing the display unit DIS of the display device DSP into display areas ARA[1,1] to ARA[m,n], and providing a drive circuit SD and a drive circuit GD in the circuit area ARD corresponding to each display area ARA, each of the display areas ARA[1,1] to ARA[m,n] can be driven independently. For example, a display area ARA that frequently rewrites image data can be driven with a higher frame frequency for the drive circuit SD and drive circuit GD in the corresponding circuit area ARD, while a display area ARA that does not frequently rewrite image data can be driven with a lower frame frequency for the drive circuit SD and drive circuit GD in the corresponding circuit area ARD. For example, the drive circuit SD and drive circuit GD corresponding to a display area ARA that frequently rewrites image data, such as video, should operate at a high frame frequency of 60Hz or higher, 120Hz or higher, 165Hz or higher, or 240Hz or higher. Furthermore, for example, the drive circuits SD and GD corresponding to the display area ARA, where image data such as still images are not frequently rewritten, can operate at low frame frequencies of 5Hz or less, 1Hz or less, 0.5Hz or less, or 0.1Hz or less. In this way, by dividing the display unit DIS of the display device DSP into display areas ARA[1,1] to ARA[m,n], the rewriting frequency (frame frequency) can be changed according to the image displayed in the display area ARA. In other words, the display device DSP can display images in two selected display areas ARA[1,1] to ARA[m,n] in the display unit DIS at different frame frequencies. 【0102】 Furthermore, by using a glass substrate, a metal substrate, or a base film for the substrate BS, the diagonal size of the display device DSP can be increased more easily than with semiconductor substrates made of silicon or other materials. In particular, by selecting a glass substrate such as a second-generation substrate size (approximately 370mm x 470mm), a third-generation substrate size (approximately 550mm x 650mm), a fourth-generation substrate size (approximately 680mm x 880mm), or a substrate size exceeding the fourth generation, it is possible to manufacture a display device DSP with a diagonal size larger than the diameter of the main silicon wafers handled in current semiconductor processes (approximately 12 inches). 【0103】 <Example of control circuit configuration> Next, we will describe examples of a display device DSP and a control circuit located outside the display device DSP. Figure 5 is a block diagram showing an example of a display device DSP and a control circuit PRPH. 【0104】 The display device DSP shown in Figure 5 comprises a display unit DIS and a drive circuit area DRV. The drive circuit area DRV also comprises a circuit GDS including multiple drive circuits GD and a circuit SDS including multiple drive circuits SD. The control circuit PRPH comprises a distribution circuit DMG, a distribution circuit DMS, a control unit CTR, a storage device MD, a voltage generation circuit PG, a timing controller TMC, a clock signal generation circuit CKS, an image processing unit GPS, and an interface INT. 【0105】 In the display device DSP, the drive circuit region DRV, which includes each of the multiple drive circuits GD, is superimposed on the pixel layer PXAL, which includes multiple display areas ARA, as shown in Figures 2A to 4B. However, in Figure 5, for convenience, the multiple drive circuits GD are shown in a single row. Similarly, the drive circuit region DRV, which includes each of the multiple drive circuits SD, is superimposed on the pixel layer PXAL, which includes multiple display areas ARA, as shown in Figures 2A to 4B. However, in Figure 5, for convenience, the multiple drive circuits SD are shown in a single row. 【0106】 The PRPH control circuit is electrically connected to the outside of the DSP display device, for example, as shown in Figures 1A to 4B. 【0107】 The distribution circuit DMG, distribution circuit DMS, control unit CTR, memory device MD, voltage generation circuit PG, timing controller TMC, clock signal generation circuit CKS, image processing unit GPS, and interface INT each transmit and receive various signals from one another via the bus wiring BW. 【0108】 The interface INT functions as a circuit that takes image information, output from an external device for displaying an image on a display device (DSP), into a circuit within the control circuit PRPH. Examples of external devices include non-volatile storage devices such as recording media players, HDDs (Hard Disk Drives), and SSDs (Solid State Drives). The interface INT may also function as a circuit that outputs signals from the circuit within the control circuit PRPH to a device outside the display device (DSP). 【0109】 Furthermore, when image information is input to interface INT from an external device via wireless communication, interface INT can be configured, for example, to include an antenna for receiving image information, a mixer, an amplification circuit, and an analog-to-digital conversion circuit. 【0110】 The control unit CTR processes various control signals sent from external devices via the interface INT and has the function of controlling various circuits included in the control circuit PRPH. 【0111】 The memory device MD has the function of temporarily holding information and image signals. In this case, the memory device MD functions, for example, as a frame memory (sometimes called a frame buffer). The memory device MD may also have the function of temporarily holding at least one of the information sent from an external device via the interface INT and the information processed by the control unit CTR. For example, at least one of SRAM (Static Random Access Memory) or DRAM (Dynamic Random Access Memory) can be used as the memory device MD. 【0112】 The voltage generation circuit PG has the function of generating power supply voltages to be supplied to the pixel circuits included in the display unit DIS and the circuits included in the control circuit PRPH. The voltage generation circuit PG may also have the function of selecting the circuits to which the voltage is supplied. For example, the voltage generation circuit PG can reduce the overall power consumption of the display device DSP by stopping the voltage supply to the circuits GDS, SDS, GPS, TMC, and CKS during the period when a still image is displayed on the display unit DIS. 【0113】 The timing controller TMC has the function of generating timing signals used by multiple drive circuits GD included in circuit GDS and multiple drive circuits SD included in circuit SDS. Furthermore, the clock signal generated by the clock signal generation circuit CKS can be used to generate the timing signals. 【0114】 The image processing unit GPS has the function of performing processing for drawing images on the display unit DIS. For example, the image processing unit GPS may have a GPU (Graphics Processing Unit). In particular, by configuring the image processing unit GPS to perform parallel pipeline processing, image data for display on the display unit DIS can be processed at high speed. The image processing unit GPS may also have the function of a decoder for restoring encoded images. 【0115】 Furthermore, in Figure 5, the image processing unit GPS has the function of receiving image data to be displayed in each of the display areas ARA[1,1] to ARA[m,n], and generating an image signal from said image data. 【0116】 Furthermore, the image processing unit GPS may have a function to correct the color tone of the image displayed in display area ARA[1,1] to display area ARA[m,n]. In this case, it is preferable that the image processing unit GPS is provided with either or both a dimming circuit and a color adjustment circuit. Also, if the display pixel circuit included in the display unit DIS includes an organic EL element, the image processing unit GPS may be provided with an EL correction circuit. 【0117】 Furthermore, artificial intelligence may be used for the image correction described above. For example, the current flowing through the display device provided in the pixel (or the voltage applied to the display device) may be monitored and acquired, the image displayed on the display unit DIS may be acquired by an image sensor, and the current (or voltage) and the image may be treated as input data for an artificial intelligence calculation (e.g., an artificial neural network), and the output result may be used to determine whether or not the image has been corrected. 【0118】 Furthermore, artificial intelligence calculations can be applied not only to image correction but also to image data upconversion. This allows for the upconversion of low-resolution image data to match the screen resolution of the display unit (DIS), enabling the display of high-quality images on the DIS. Artificial intelligence calculations can also be applied to image data downconversion. 【0119】 Furthermore, the artificial intelligence calculations described above can be performed using, for example, the GPU included in the image processing unit GPS. In other words, various correction calculations (for example, color uniformity correction or upscaling) can be performed using the GPU. 【0120】 In this specification, a GPU that performs artificial intelligence calculations will be referred to as an AI accelerator. In other words, in this specification, the term GPU may sometimes be replaced with AI accelerator in explanations. 【0121】 The clock signal generation circuit CKS has the function of generating clock signals for displaying desired images in each of the display areas ARA[1,1] to ARA[m,n], for example. 【0122】 Furthermore, if the image rewriting frequency (frame frequency) differs in each of the display areas ARA[1,1] to ARA[m,n], it is preferable that the clock signal generation circuit CKS has the function of generating clock signals with frame frequencies corresponding to each of the display areas ARA[1,1] to ARA[m,n]. In other words, it is preferable that the clock signal generation circuit CKS has the function of simultaneously generating clock signals with different frequencies. 【0123】 The distribution circuit DMG has the function of transmitting a signal received from the bus wiring BW to a drive circuit GD that drives a pixel included in any one of the display areas ARA[1,1] to ARA[m,n], according to the content of the signal. 【0124】 The distribution circuit DMS has the function of transmitting a signal received from the bus wiring BW to a drive circuit SD that drives a pixel included in one of the display areas ARA[1,1] to ARA[m,n], according to the content of the signal. 【0125】 Note that while Figure 5 illustrates how the distribution circuit DMG directly transmits a signal to the circuit GDS, the signal transmitted from the distribution circuit DMG may also be input to the circuit GDS via the interface INT. Similarly, while Figure 5 illustrates how the distribution circuit DMS directly transmits a signal to the circuit SDS, the signal transmitted from the distribution circuit DMS may also be input to the circuit SDS via the interface INT. 【0126】 Although not shown in Figure 5, the PRPH control circuit may also include a level shifter. For example, a level shifter has the function of converting the signals input to each circuit to an appropriate level. 【0127】 Note that the configuration of the control circuit PRPH shown in Figure 5 is just one example, and the circuit configuration included in the control circuit PRPH may be changed depending on the situation. For example, if the control circuit PRPH is configured to receive the drive voltage for each circuit from an external source, it is not necessary to generate the drive voltage within the control circuit PRPH, and in this case, the control circuit PRPH may be configured without a voltage generation circuit PG. 【0128】 Furthermore, for example, all or part of the circuits included in the control circuit PRPH may be included in the circuit layer SICL of the display device DSP. Specifically, in the case of the display device DSP of Figure 1A, all or part of the circuits included in the control circuit PRPH may be included in the drive circuit region DRV. Also, in the case of the display device DSP of Figure 1B, all or part of the circuits included in the control circuit PRPH may be included in the drive circuit region DRV or region LIA. 【0129】 This embodiment can be appropriately combined with other embodiments shown in this specification. 【0130】 (Embodiment 2) This embodiment describes a display device that can be provided in an electronic device according to one aspect of the present invention. The display device DSP described in the above embodiment can be replaced with the display device described in this embodiment. 【0131】 <Example of display device configuration> Figure 6 is a cross-sectional view showing an example of a display device according to one embodiment of the present invention. The display device 1000 shown in Figure 6 has a configuration in which a pixel circuit, a driving circuit, etc., are provided on a substrate 310, for example. The configuration of the display device DSP of the embodiment described above can be the same as the configuration of the display device 1000 in Figure 6. 【0132】 Specifically, for example, the circuit layer SICL and the pixel layer PXAL shown in the display device DSP of Figure 1 can be configured as shown in the display device 1000 of Figure 6. The display device 1000 of Figure 6 has a configuration in which circuit elements and light-emitting devices are formed between substrate 310 and substrate 110. The circuit layer SICL has a transistor 300. Specifically, the transistor 300 is formed on substrate 310. The pixel layer PXAL is provided above the transistor 300. Wiring is provided to electrically connect the transistor 300 and the transistor 200 (not shown). The pixel layer PXAL, as an example, has a transistor 200 and a light-emitting device 130 (in Figure 6, light-emitting devices 130R, 130G, and 130B). The substrate 110 is provided above the light-emitting device 130. 【0133】 The substrate 310 corresponds, for example, to the substrate BS described in Embodiment 1. Therefore, it is preferable to use a substrate that can be applied to substrate BS, as described in Embodiment 1. 【0134】 As described in Embodiment 1, the diagonal size of the display device DSP can be determined by the size of the substrate applied to the substrate BS (substrate 310). In particular, by using a glass substrate, metal substrate, or base film, which are easily made to increase the area, a display device DSP with a large diagonal size can be manufactured. In this specification, etc., an increased-area substrate refers to, for example, a substrate of second-generation size or larger. 【0135】 In this embodiment, the substrate 310 is described as a substrate made of a material with high heat resistance, such as a glass substrate. 【0136】 Furthermore, when the substrate BS (substrate 310) is made larger in area, it is preferable that the transistors 300 and 200 be formed using a process that is capable of forming even on a large-area substrate BS (substrate 310). Examples of transistors that can be formed on a large-area substrate include transistors containing low-temperature polysilicon in the channel formation region (hereinafter referred to as LTPS transistors) and OS transistors. 【0137】 The transistor 300 is provided on a substrate 310. The transistor 300 has an insulator 311, an insulator 312, an insulator 313, an insulator 314, a conductor 316, a conductor 317, a low-resistance region 318p, a semiconductor region 318i, and a conductor 319. Here, the same hatching pattern is applied to multiple layers obtained by processing the same conductive film. In this specification, the low-resistance region 318p and the semiconductor region 318i are collectively referred to as the semiconductor layer 318. In particular, by applying, for example, low-temperature polysilicon to the semiconductor material contained in the semiconductor layer 318, the transistor 300 can be made into an LTPS transistor. LTPS transistors have high field-effect mobility and good frequency characteristics. 【0138】 By applying an LTPS transistor to transistor 300, the circuits provided in the circuit layer SICL (for example, the drive circuits GD and SD shown in Figures 2B to 5) can be fabricated on the same substrate as the display unit. This simplifies the external circuits mounted on the display device, reducing component costs and mounting costs. 【0139】 Furthermore, in Figure 6, the conductor 317 functions as the first gate (sometimes referred to as the gate or back gate) in the transistor 300. The conductor 316 functions as the second gate (sometimes referred to as the gate or the other back gate) in the transistor 300. In addition, one of the pair of low-resistance regions 318p of the semiconductor layer 318 functions as either the source or the drain in the transistor 300, and the other of the pair of low-resistance regions 318p of the semiconductor layer 318 functions as either the source or the drain in the transistor 300. Furthermore, the insulator 313 functions as the first gate insulating film in the transistor 300, and the insulator 312 functions as the second gate insulating film in the transistor 300. 【0140】 In Figure 6, an insulator 311 is formed on the substrate 310. A conductor 316 is formed on a portion of the insulator 311. An insulator 312 is formed so as to cover the insulator 311 and the conductor 316. A semiconductor layer 318 is formed superimposed on the conductor 316 and the insulator 312, and on a portion of the insulator 312. An insulator 313 is formed so as to cover the insulator 312 and the semiconductor layer 318. A conductor 317 is formed superimposed on the conductor 316, the insulator 312, the semiconductor layer 318, and the insulator 313, and on a portion of the insulator 313. An insulator 314 is sequentially covered so as to cover the insulator 313 and the conductor 317. Furthermore, openings are provided in the regions of the insulators 313 and 314 superimposed on the low-resistance region 318p, and a conductor 319 is formed on the insulator 314 so as to fill these openings. 【0141】 For insulators 311, 312, 313, and 314, for example, silicon oxide, silicon oxide nitride, silicon oxide nitride, silicon nitride, aluminum oxide, aluminum oxide nitride, aluminum oxide nitride, aluminum nitride, etc. may be used. 【0142】 In this specification, the term "oxide-nitride" refers to a material in which the oxygen content is greater than the nitrogen content, and the term "nitride oxide" refers to a material in which the nitrogen content is greater than the oxygen content. For example, when "silicon oxynitride" is written, it refers to a material in which the oxygen content is greater than the nitrogen content, and when "silicon nitride oxide" is written, it refers to a material in which the nitrogen content is greater than the oxygen content. 【0143】 In particular, it is preferable to use a barrier insulating film for the insulator 311 that prevents the diffusion of impurities (e.g., metal ions, metal atoms, oxygen atoms, oxygen molecules, hydrogen atoms, hydrogen molecules, and water molecules) from the region below the insulator 311 (e.g., the substrate 310). 【0144】 Similarly, it is preferable to use a barrier insulating film for the insulator 314 that prevents the diffusion of impurities (e.g., specific metal ions, specific metal atoms, oxygen atoms, oxygen molecules, hydrogen atoms, hydrogen molecules, and water molecules) from the region above the insulator 314 (e.g., the region where the transistor 200, light-emitting device 130R, light-emitting device 130G, and light-emitting device 130B are provided). 【0145】 Therefore, it is preferable that insulators 311 and 314 be made of insulating materials that have the function of suppressing the diffusion of impurities such as specific metal ions, specific metal atoms, oxygen atoms, oxygen molecules, hydrogen atoms, hydrogen molecules, and water molecules (i.e., materials that do not easily permeate the above-mentioned impurities). Furthermore, depending on the circumstances, it is preferable that insulators 311 and 314 be made of insulating materials that have the function of suppressing the diffusion of impurities such as nitrogen atoms, nitrogen molecules, nitrogen oxide molecules (e.g., N2O, NO, or NO2), and copper atoms (i.e., materials that do not easily permeate the above-mentioned oxygen). 【0146】 As an example of a film with hydrogen barrier properties, silicon nitride formed by the CVD (Chemical Vapor Deposition) method can be used. 【0147】 The amount of hydrogen desorption can be analyzed, for example, using a thermal desorption gas analysis (TDS) method. For example, in TDS analysis, the amount of hydrogen desorption from insulator 311 or insulator 314, when the film surface temperature ranges from 50°C to 500°C, is calculated as 10 × 10¹⁶ hydrogen atoms per unit area of ​​insulator 324. 15 atoms / cm 2 The following is preferably 5 × 10 15 atoms / cm 2 The following is acceptable. 【0148】 As described above, the semiconductor layer 318 contains silicon. In particular, it is preferable that the silicon be low-temperature polysilicon. That is, it is preferable that the transistor 300 be an LTPS transistor. 【0149】 Incidentally, since fabricating p-type semiconductors using metal oxides is difficult from the viewpoint of mobility and reliability, circuits composed of OS transistors are often n-channel unipolar circuits. On the other hand, since LTPS transistors can be easily fabricated in either n-channel or p-channel form, CMOS circuits can be constructed using LTPS transistors. As explained in Embodiment 1, since the circuit layer SICL has a drive circuit, it is preferable for the drive circuit to be composed of a CMOS circuit rather than a unipolar circuit from the viewpoint of drive speed and power consumption. 【0150】 The low-resistance region 318p is a region containing impurity elements. For example, if transistor 300 is an n-channel type, impurity elements such as phosphorus or arsenic may be added to the low-resistance region 318p. On the other hand, if transistor 300 is a p-channel type, impurity elements such as boron or aluminum may be added to the low-resistance region 318p. Furthermore, the aforementioned impurity elements may be added to the semiconductor region 318i in order to control the threshold voltage of transistor 300. 【0151】 The transistor 300 may be either a p-channel or n-channel type. Alternatively, multiple transistors 300 may be provided in the circuit layer SICL, allowing the use of both p-channel and n-channel types. 【0152】 For conductors 316 and 317, metals such as aluminum, titanium, chromium, nickel, copper, yttrium, zirconium, molybdenum, silver, tantalum, or tungsten can be used. Alternatively, conductors 316 and 317 can be made of alloys mainly composed of one or more of the above-mentioned metals, in a single-layer or multilayer structure. Alternatively, conductors 316 and 317 may be made of light-transmitting conductive materials such as indium oxide, indium tin oxide (ITO), indium oxide containing tungsten, indium zinc oxide containing tungsten, indium oxide containing titanium, ITO containing titanium, indium zinc oxide, zinc oxide (ZnO), ZnO containing gallium, or indium tin oxide containing silicon. Alternatively, conductors 316 and 317 may be made of semiconductors such as polycrystalline silicon or oxide semiconductors, or silicides such as nickel silicide, whose resistance has been reduced by means of including impurity elements. Alternatively, conductors 316 and 317 may be made of a film containing graphene. The film containing graphene can be formed, for example, by reducing a film containing graphene oxide. Alternatively, it may be formed using a conductive paste such as silver, carbon, or copper, or a conductive polymer such as polythiophene. Conductive pastes are inexpensive and therefore preferred. Conductive polymers are easy to apply and therefore preferred. 【0153】 The conductor 319 functions as wiring electrically connected to the low-resistance region 318p of the transistor 300. In other words, the conductor 319 functions as either a source or a drain in the transistor 300. The conductor 319 can be made from the same material as the conductors 316 and 317. 【0154】 Note that the transistor 300 shown in Figure 6 is just one example, and its structure is not limited to that example. An appropriate transistor may be used depending on the circuit configuration, driving method, etc. 【0155】 Insulator 320 and insulator 322 are formed sequentially on insulator 314. 【0156】 For insulators 320 and 322, materials applicable to any one of insulators 311 to 314 can be used. 【0157】 Multiple transistors 200 are formed on the insulator 322. These multiple transistors 200 can be manufactured, for example, using the same material and the same process. 【0158】 Insulators 211, 213, 215, and 214 are provided on the insulator 322 in this order. A portion of insulator 211 functions as a gate insulating layer for each transistor. A portion of insulator 213 functions as a gate insulating layer for each transistor. Insulator 215 is provided covering the transistors. Insulator 214 is provided covering the transistors and functions as a planarization layer. The number of gate insulating layers and insulating layers covering the transistors are not limited and may be a single layer or a stack of two or more layers. 【0159】 It is preferable to use a material that does not easily allow impurities such as water and hydrogen to diffuse into at least one layer of the insulating layer covering the transistor. This allows the insulating layer to function as a barrier layer. With such a configuration, the diffusion of impurities from the outside into the transistor can be effectively suppressed, thereby improving the reliability of the display device. 【0160】 It is preferable to use an inorganic insulating film for insulators 211, 213, and 215, respectively. Examples of inorganic insulating films include silicon nitride film, silicon oxynitride film, silicon oxide film, silicon nitride oxide film, aluminum oxide film, or aluminum nitride film. Alternatively, examples of inorganic insulating films include hafnium oxide film, yttrium oxide film, zirconium oxide film, gallium oxide film, tantalum oxide film, magnesium oxide film, lanthanum oxide film, cerium oxide film, or neodymium oxide film. Furthermore, two or more of the above insulating films may be laminated and used. 【0161】 An organic insulating layer is preferred for the insulator 214, which functions as a planarization layer. Materials that can be used for the organic insulating layer include acrylic resin, polyimide resin, epoxy resin, polyamide resin, polyimidoamide resin, siloxane resin, benzocyclobutene resin, phenol resin, and precursors of these resins. Alternatively, the insulator 214 may have a laminated structure of an organic insulating layer and an inorganic insulating layer. The outermost layer of the insulator 214 preferably functions as an etching protection layer. This suppresses the formation of recesses in the insulator 214 during processing of conductors 112a, 126a, or 129a, as described later. Alternatively, recesses may be provided in the insulator 214 during processing of conductors 112a, 126a, or 129a. 【0162】 Multiple transistors 200 each have a conductor 221 that functions as a gate, an insulator 211 that functions as a gate insulating layer, conductors 222a and 222b that function as source and drain, a semiconductor layer 231, an insulator 213 that functions as a gate insulating layer, and a conductor 223 that functions as a gate. Here, as with transistor 300, the same hatching pattern is applied to multiple layers obtained by processing the same conductive film. Insulator 211 is located between conductor 221 and semiconductor layer 231. Insulator 213 is located between conductor 223 and semiconductor layer 231. 【0163】 The transistor structure of the display device of this embodiment is not particularly limited. For example, planar transistors, staggered transistors, inverse staggered transistors, etc., can be used. Furthermore, either a top-gate or bottom-gate transistor structure may be used. Alternatively, gates may be provided above and below the semiconductor layer in which the channel is formed. 【0164】 Each of the multiple transistors 200 is configured in which a semiconductor layer on which a channel is formed is sandwiched between two gates. The transistor may be driven by connecting the two gates and supplying them with the same signal. Alternatively, the threshold voltage of the transistor may be controlled by applying a potential to control the threshold voltage to one of the two gates and a potential to drive the other. 【0165】 The crystallinity of the semiconductor material used in the transistor is not particularly limited; amorphous semiconductors, crystalline semiconductors (microcrystalline semiconductors, polycrystalline semiconductors, single-crystal semiconductors, or semiconductors with crystalline regions in part) may be used. Using a crystalline semiconductor is preferable because it can suppress the degradation of transistor characteristics. 【0166】 The semiconductor layer of the transistor preferably has a metal oxide (also called an oxide semiconductor). In other words, the display device of this embodiment preferably uses a transistor (hereinafter referred to as an OS transistor) that uses a metal oxide in the channel formation region. 【0167】 Examples of crystalline oxide semiconductors include CAAC (c-axis-aligned crystalline)-OS and nc (nanocrystalline)-OS. 【0168】 The OS transistor has an extremely high field-effect mobility as compared with a transistor using amorphous silicon. Further, the OS transistor has an extremely small leakage current between the source and the drain in the off state (hereinafter also referred to as the off current), and can hold the charge accumulated in the capacitor connected in series with the transistor for a long period of time. Further, by applying the OS transistor, the power consumption of the display device can be reduced. 【0169】 Further, the off-current value of the OS transistor per 1 μm channel width at room temperature is 1 aA (1 × 10 -18 A) or less, 1 zA (1 × 10 -21 A) or less, or 1 yA (1 × 10 -24 A) or less. Note that the off-current value of the Si transistor per 1 μm channel width at room temperature is 1 fA (1 × 10 -15 A) or more and 1 pA (1 × 10 -12 A) or less. Therefore, it can be said that the off-current of the OS transistor is about 10 digits lower than the off-current of the Si transistor. 【0170】 Further, when increasing the emission luminance of the light-emitting device included in the pixel circuit, it is necessary to increase the amount of current flowing through the light-emitting device. For that purpose, it is necessary to increase the voltage between the source and the drain of the driving transistor included in the pixel circuit. The OS transistor has a higher breakdown voltage between the source and the drain as compared with the Si transistor, and thus a high voltage can be applied between the source and the drain of the OS transistor. Therefore, by using the OS transistor as the driving transistor included in the pixel circuit, the amount of current flowing through the light-emitting device can be increased, and the emission luminance of the light-emitting device can be increased. 【0171】 Furthermore, when the transistor operates in the saturation region, OS transistors exhibit smaller changes in source-drain current in response to changes in gate-source voltage compared to Si transistors. Therefore, by using OS transistors as driving transistors in the pixel circuit, the current flowing between the source and drain can be precisely controlled by changes in gate-source voltage, thereby controlling the amount of current flowing to the light-emitting device. This allows for a wider range of tonal gradations in the pixel circuit. 【0172】 Furthermore, in terms of the saturation characteristics of the current flowing when a transistor operates in the saturation region, OS transistors can supply a more stable current (saturation current) than Si transistors, even when the source-drain voltage gradually increases. Therefore, by using an OS transistor as a driving transistor, a stable current can be supplied to a light-emitting device even if there are variations in the current-voltage characteristics of the light-emitting device. In other words, when operating in the saturation region, the source-drain current remains almost unchanged even when the source-drain voltage is increased, thus stabilizing the luminescence brightness of the light-emitting device. 【0173】 As described above, by using OS transistors in the drive transistors included in the pixel circuit, it is possible to suppress black level distortion, increase luminescence brightness, enable multi-gradation, and suppress variations in light-emitting devices. 【0174】 The semiconductor layer of the OS transistor preferably contains, for example, at least indium or zinc, and more preferably indium and zinc. For example, the semiconductor layer preferably contains indium, M (where M is one or more selected from gallium, aluminum, yttrium, tin, silicon, boron, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, magnesium, and cobalt), and zinc. In particular, M is preferably one or more selected from gallium, aluminum, yttrium, and tin. 【0175】 In particular, it is preferable to use an oxide containing indium (In), gallium (Ga), and zinc (Zn) (also written as IGZO) as the semiconductor layer. Alternatively, it is preferable to use an oxide containing indium, tin, and zinc. Alternatively, it is preferable to use an oxide containing indium, gallium, tin, and zinc. Alternatively, it is preferable to use an oxide containing indium (In), aluminum (Al), and zinc (Zn) (also written as IAZO). Alternatively, it is preferable to use an oxide containing indium (In), aluminum (Al), gallium (Ga), and zinc (Zn) (also written as IAGZO). 【0176】 When the semiconductor layer is an In-M-Zn oxide, it is preferable that the atomic ratio of In in the In-M-Zn oxide is greater than or equal to the atomic ratio of M. Possible atomic ratios of metal elements in such an In-M-Zn oxide include: In:M:Zn=1:1:1 or near that composition, In:M:Zn=1:1:1.2 or near that composition, In:M:Zn=1:3:2 or near that composition, In:M:Zn=1:3:4 or near that composition, In:M:Zn=2:1:3 or near that composition, In:M:Zn=3:1:2 or near that composition, and In:M:Zn=4:2:3 Examples include compositions near the desired atomic ratio, such as In:M:Zn=4:2:4.1 or near that ratio, In:M:Zn=5:1:3 or near that ratio, In:M:Zn=5:1:6 or near that ratio, In:M:Zn=5:1:7 or near that ratio, In:M:Zn=5:1:8 or near that ratio, In:M:Zn=6:1:6 or near that ratio, In:M:Zn=5:2:5 or near that ratio, etc. Note that "nearby composition" includes a range of ±30% of the desired atomic ratio. 【0177】 For example, when describing a composition with an atomic ratio of In:Ga:Zn = 4:2:3 or a similar ratio, it includes cases where, when In is set to 4, Ga is between 1 and 3, and Zn is between 2 and 4. Also, when describing a composition with an atomic ratio of In:Ga:Zn = 5:1:6 or a similar ratio, it includes cases where, when In is set to 5, Ga is greater than 0.1 and 2 or less, and Zn is between 5 and 7. Furthermore, when describing a composition with an atomic ratio of In:Ga:Zn = 1:1:1 or a similar ratio, it includes cases where, when In is set to 1, Ga is greater than 0.1 and 2 or less, and Zn is greater than 0.1 and 2 or less. 【0178】 Furthermore, the structure of the OS transistor is not limited to the structure shown in Figure 6. For example, the structures shown in Figures 7A and 7B may also be used. 【0179】 Transistors 200A and 200B each have a conductor 221 that functions as a gate, an insulator 211 that functions as a gate insulating layer, a semiconductor layer 231 having a channel forming region 231i and a pair of low-resistance regions 231n, a conductor 222a connected to one of the pair of low-resistance regions 231n, a conductor 222b connected to the other of the pair of low-resistance regions 231n, an insulator 225 that functions as a gate insulating layer, a conductor 223 that functions as a gate, and an insulator 215 covering the conductor 223. The insulator 211 is located between the conductor 221 and the channel forming region 231i. The insulator 225 is located at least between the conductor 223 and the channel forming region 231i. Furthermore, an insulator 218 covering the transistor may be provided. 【0180】 In the transistor 200A shown in Figure 7A, an example is shown where the insulator 225 covers the top and side surfaces of the semiconductor layer 231. Conductors 222a and 222b are connected to the low-resistance region 231n through openings provided in the insulators 225 and 215, respectively. Of the conductors 222a and 222b, one functions as a source and the other as a drain. 【0181】 On the other hand, in transistor 200B shown in Figure 7B, the insulator 225 overlaps with the channel formation region 231i of the semiconductor layer 231, but does not overlap with the low-resistance region 231n. For example, the structure shown in Figure 7B can be fabricated by processing the insulator 225 using the conductor 223 as a mask. In Figure 7B, an insulator 215 is provided covering the insulator 225 and the conductor 223, and the conductors 222a and 222b are connected to the low-resistance region 231n, respectively, through openings in the insulator 215. 【0182】 A light-emitting device 130R, a light-emitting device 130G, a light-emitting device 130B, and a connection portion 140 are formed on the insulator 214. 【0183】 The connection portion 140 is sometimes called the cathode contact portion and is electrically connected to the cathode electrodes of the light-emitting devices 130R, 130G, and 130B, respectively. In Figure 6, the connection portion 140 includes one or more conductors selected from conductors 112a to 112c, one or more conductors selected from conductors 126a to 126c, one or more conductors selected from conductors 129a to 129c, a common layer 114 (described later), and a common electrode 115 (described later). 【0184】 The connection portion 140 may be provided so as to surround all four sides of the display unit, or it may be provided inside the display unit (for example, between adjacent light-emitting devices 130). 【0185】 The light-emitting device 130R includes a conductor 112a, a conductor 126a on the conductor 112a, and a conductor 129a on the conductor 126a. All of the conductors 112a, 126a, and 129a can be called pixel electrodes, or only a part of them can be called pixel electrodes. 【0186】 The light-emitting device 130G includes a conductor 112b, a conductor 126b on the conductor 112b, and a conductor 129b on the conductor 126b. Similar to the light-emitting device 130R, all of the conductors 112b, 126b, and 129b can be called pixel electrodes, or only a part of them can be called pixel electrodes. 【0187】 The light-emitting device 130B includes a conductor 112c, a conductor 126c on the conductor 112c, and a conductor 129c on the conductor 126c. Similar to the light-emitting devices 130R and 130G, all of the conductors 112c, 126c, and 129c can be called pixel electrodes, or only a portion of them can be called pixel electrodes. 【0188】 Conductors 112a to 112c and conductors 126a to 126c may be fitted with a conductive layer that functions as a reflective electrode, for example. As the conductive layer that functions as a reflective electrode, a conductor with high reflectivity to visible light can be used, for example, silver, aluminum, or an alloy film of silver (Ag), palladium (Pd), and copper (Cu) (Ag-Pd-Cu(APC) film). Alternatively, conductors 112a to 112c and conductors 126a to 126c may be a laminated film of aluminum sandwiched between a pair of titanium (a laminated film in the order of Ti, Al, Ti), or a laminated film of silver sandwiched between a pair of indium tin oxides (a laminated film in the order of ITO, Ag, ITO). 【0189】 Alternatively, for example, a conductive layer that functions as a reflective electrode may be used in conductors 112a to 112c, and a highly transparent conductor may be used in conductors 126a to 126c. Examples of highly transparent conductors include indium tin oxide (sometimes called ITO) or an alloy of silver and magnesium. 【0190】 For example, conductive layers that function as transparent electrodes can be used for the conductors 129a to 129c. As the conductive layer that functions as a transparent electrode, for example, the highly light-transmitting conductor described above can be used. 【0191】 Furthermore, a microcavity structure (micro-resonator structure) may be provided in the light-emitting device 130, which will be described in detail later. A microcavity structure refers to a structure in which the distance between the lower surface of the light-emitting layer and the upper surface of the lower electrode is set to a thickness corresponding to the wavelength of the color of light emitted by the light-emitting layer. In this case, it is preferable to use a conductive material having light-transmitting and light-reflecting properties for the conductors 129a to 129c, which are the upper electrodes (common electrodes), and to use a conductive material having light-reflecting properties for the conductors 112a to 112c and 126a to 126c, which are the lower electrodes (pixel electrodes). 【0192】 A microcavity structure refers to a structure in which the optical distance between the lower electrode and the light-emitting layer is adjusted to (2n-1)λ / 4 (where n is a natural number greater than or equal to 1, and λ is the wavelength of the light to be amplified). As a result, the light reflected back by the lower electrode (reflected light) interferes significantly with the light that directly enters the upper electrode from the light-emitting layer (incident light). Therefore, the phases of the reflected light and the incident light, both of which have wavelengths of λ, can be matched, and the light emitted from the light-emitting layer can be further amplified. On the other hand, if the reflected light and the incident light have wavelengths other than λ, the phases will not match, and the light will attenuate without resonance. 【0193】 Conductor 112a is connected to conductor 222b of transistor 200 through an opening provided in insulator 214. The end of conductor 126a is located outside the end of conductor 112a. The ends of conductor 126a and conductor 129a are aligned or approximately aligned. 【0194】 The conductors 112b, 126b, and 129b in the light-emitting device 130G, and conductors 112c, 126c, and 129c in the light-emitting device 130B, are the same as conductors 112a, 126a, and 129a in the light-emitting device 130R, so a detailed explanation is omitted. 【0195】 The conductors 112a, 112b, and 112c have recesses formed in them so as to cover the openings provided in the insulator 214. Layer 128 is embedded in these recesses. 【0196】 Layer 128 has the function of flattening the recesses of conductors 112a, 112b, and 112c. In the light-emitting device 130R, a conductor 126a is provided on conductor 112a and on layer 128, which is electrically connected to conductor 112a. Similarly, in the light-emitting device 130G, a conductor 126b is provided on conductor 112b and on layer 128, which is electrically connected to conductor 112b. Similarly, in the light-emitting device 130B, a conductor 126c is provided on conductor 112c and on layer 128, which is electrically connected to conductor 112c. Therefore, regions overlapping with the recesses of conductors 112a, 112b, and 112c can also be used as light-emitting regions, thereby increasing the aperture ratio of the pixels. 【0197】 Layer 128 may be an insulating layer or a conductive layer. Various inorganic insulating materials, organic insulating materials, and conductive materials can be used for layer 128 as appropriate. In particular, it is preferable that layer 128 be formed using an insulating material. 【0198】 As layer 128, an insulating layer having an organic material can be suitably used. For example, acrylic resin, polyimide resin, epoxy resin, polyamide resin, polyimidoamide resin, siloxane resin, benzocyclobutene resin, phenol resin, and precursors of these resins can be used as layer 128. Alternatively, a photosensitive resin can be used as layer 128. The photosensitive resin can be a positive-type material or a negative-type material. 【0199】 By using a photosensitive resin, layer 128 can be fabricated using only exposure and development processes, thereby reducing the impact on the surfaces of conductors 112a, 112b, and 112c due to dry etching or wet etching. Furthermore, by forming layer 128 using a negative-type photosensitive resin, it may be possible to form layer 128 using the same photomask (exposure mask) used to form the openings in the insulator 214. 【0200】 Although Figure 6 shows an example in which the upper surface of layer 128 has a flat portion, the shape of layer 128 is not particularly limited. Figures 7C to 7E show modified examples of layer 128. 【0201】 As shown in Figures 7C and 7E, the upper surface of layer 128 can be configured to have a shape in which the center and its vicinity are recessed in a cross-sectional view, that is, a shape having a concave curved surface. 【0202】 Furthermore, as shown in Figure 7D, the upper surface of layer 128 can be configured to have a shape that bulges in the center and its vicinity when viewed in cross-section, that is, a shape with a convex curved surface. 【0203】 Furthermore, the upper surface of layer 128 may have one or both of a convex and a concave surface. Also, the number of convex and concave surfaces on the upper surface of layer 128 is not limited and can be one or more. 【0204】 Furthermore, the height of the top surface of layer 128 and the height of the top surface of the conductor 112a may be the same or approximately the same, or they may be different from each other. For example, the height of the top surface of layer 128 may be lower or higher than the height of the top surface of the conductor 112a. 【0205】 Furthermore, Figure 7C can be seen as an example in which the layer 128 is housed inside a recess formed in the conductor 112a. On the other hand, as shown in Figure 7E, the layer 128 may be located outside the recess formed in the conductor 112a, meaning that the width of the upper surface of the layer 128 may be wider than that of the recess. 【0206】 Light-emitting device 130R has a first layer 113a, a common layer 114 on the first layer 113a, and a common electrode 115 on the common layer 114. Light-emitting device 130G has a second layer 113b, a common layer 114 on the second layer 113b, and a common electrode 115 on the common layer 114. Light-emitting device 130B has a third layer 113c, a common layer 114 on the third layer 113c, and a common electrode 115 on the common layer 114. 【0207】 The first layer 113a is formed to cover the top and side surfaces of conductor 126a and conductor 129a. Similarly, the second layer 113b is formed to cover the top and side surfaces of conductor 126b and conductor 129b. Similarly, the third layer 113c is formed to cover the top and side surfaces of conductor 126c and conductor 129c. Therefore, the entire region where conductors 126a, 126b, and 126c are provided can be used as the light-emitting region of light-emitting devices 130R, 130G, and 130B, thereby increasing the aperture ratio of the pixels. 【0208】 In the light-emitting device 130R, the first layer 113a and the common layer 114 can be collectively referred to as the EL layer. Similarly, in the light-emitting device 130G, the second layer 113b and the common layer 114 can be collectively referred to as the EL layer. Similarly, in the light-emitting device 130B, the third layer 113c and the common layer 114 can be collectively referred to as the EL layer. 【0209】 The configuration of the light-emitting device in this embodiment is not particularly limited and may be a single structure or a tandem structure. 【0210】 The first layer 113a, the second layer 113b, and the third layer 113c are processed into island-like structures using photolithography. As a result, the first layer 113a, the second layer 113b, and the third layer 113c each have an angle of nearly 90 degrees between the top surface and the side surface at their edges. On the other hand, organic films formed using FMM (Fine Metal Mask) or the like tend to gradually thin out towards the edges, and for example, the top surface is formed in a sloping shape over a range of 1 μm to 10 μm, making it difficult to distinguish between the top surface and the side surface. 【0211】 The first layer 113a, the second layer 113b, and the third layer 113c have a clear distinction between their top and side surfaces. As a result, in adjacent first layer 113a and second layer 113b, one side surface of the first layer 113a and one side surface of the second layer 113b are positioned opposite each other. This is true for any combination of the first layer 113a, the second layer 113b, and the third layer 113c. 【0212】 The first layer 113a, the second layer 113b, and the third layer 113c each have at least an emissive layer. For example, it is preferable that the first layer 113a has an emissive layer that emits red light, the second layer 113b has an emissive layer that emits green light, and the third layer 113c has an emissive layer that emits blue light. In addition, each emissive layer may be made of a color other than those mentioned above, such as cyan, magenta, yellow, or white. 【0213】 Furthermore, the first layer 113a, the second layer 113b, and the third layer 113c may each have one or more of the following: a hole injection layer, a hole transport layer, a hole blocking layer, a charge generation layer, an electron blocking layer, an electron transport layer, and an electron injection layer. 【0214】 For example, the first layer 113a, the second layer 113b, and the third layer 113c may have a hole injection layer, a hole transport layer, an emissive layer, and an electron transport layer. An electron blocking layer may also be present between the hole transport layer and the emissive layer. Furthermore, an electron injection layer may be present on the electron transport layer. 【0215】 Furthermore, for example, the first layer 113a, the second layer 113b, and the third layer 113c may have an electron injection layer, an electron transport layer, an emissive layer, and a hole transport layer in that order. A hole blocking layer may also be present between the electron transport layer and the emissive layer. Additionally, a hole injection layer may be present on the hole transport layer. 【0216】 Preferably, the first layer 113a, the second layer 113b, and the third layer 113c each have an emissive layer and a carrier transport layer (electron transport layer or hole transport layer) on the emissive layer. Since the surfaces of the first layer 113a, the second layer 113b, and the third layer 113c may be exposed during the manufacturing process of the display device, providing the carrier transport layer on the emissive layer suppresses exposure of the emissive layer to the outermost surface and reduces damage to the emissive layer. This improves the reliability of the light-emitting device. 【0217】 Furthermore, the first layer 113a, the second layer 113b, and the third layer 113c may have, for example, a configuration comprising a first light-emitting unit, a charge-generating layer, and a second light-emitting unit. For example, it is preferable that the first layer 113a has two or more light-emitting units that emit red light, the second layer 113b has two or more light-emitting units that emit green light, and the third layer 113c has two or more light-emitting units that emit blue light. 【0218】 The second light-emitting unit preferably includes a light-emitting layer and a carrier transport layer (electron transport layer or hole transport layer) on the light-emitting layer. Since the surface of the second light-emitting unit is exposed during the manufacturing process of the display device, providing the carrier transport layer on the light-emitting layer suppresses exposure of the light-emitting layer to the outermost surface, thereby reducing damage to the light-emitting layer. This improves the reliability of the light-emitting device. 【0219】 The common layer 114 may have, for example, an electron injection layer or a hole injection layer. Alternatively, the common layer 114 may have an electron transport layer and an electron injection layer stacked together, or a hole transport layer and a hole injection layer stacked together. The common layer 114 is shared by the light-emitting device 130R, the light-emitting device 130G, and the light-emitting device 130B. 【0220】 Furthermore, the common electrode 115 is shared by light-emitting devices 130R, 130G, and 130B. As shown in Figure 6, the common electrode 115, which is shared by multiple light-emitting devices, is electrically connected to a conductor included in the connection part 140. 【0221】 The sides of the first layer 113a, the second layer 113b, and the third layer 113c are covered by insulators 125 and 127, respectively. A mask layer 118a is located between the first layer 113a and insulator 125. A mask layer 118a is also located between the second layer 113b and insulator 125, and a mask layer 118a is located between the third layer 113c and insulator 125. A common layer 114 is provided on the first layer 113a, the second layer 113b, the third layer 113c, insulator 125, and insulator 127, and a common electrode 115 is provided on the common layer 114. The common layer 114 and the common electrode 115 are each continuous films provided in common to multiple light-emitting devices. 【0222】 Furthermore, protective layers 131 are provided on light-emitting devices 130R, 130G, and 130B, respectively. The protective layer 131 functions as a passivation film that protects the light-emitting devices 130. By providing the protective layer 131 that covers the light-emitting devices, it is possible to suppress the ingress of impurities such as water into the light-emitting devices and improve the reliability of the light-emitting devices 130. 【0223】 For example, aluminum oxide, silicon nitride, or silicon nitride oxide can be used for the protective layer 131. 【0224】 The protective layer 131 and the substrate 110 are bonded together via the adhesive layer 107. For sealing the light-emitting device, a solid sealing structure or a hollow sealing structure can be applied. In Figure 6, the space between the substrate 310 and the substrate 110 is filled with the adhesive layer 107, demonstrating a solid sealing structure. Alternatively, the space may be filled with an inert gas (e.g., nitrogen or argon), demonstrating a hollow sealing structure. In this case, the adhesive layer 107 may be provided so as not to overlap with the light-emitting device. Furthermore, the space may be filled with a resin different from the frame-shaped adhesive layer 107. 【0225】 Various types of curing adhesives can be used for the adhesive layer 107, including UV-curing adhesives, reaction-curing adhesives, thermosetting adhesives, and anaerobic adhesives. Examples of these adhesives include epoxy resins, acrylic resins, silicone resins, phenolic resins, polyimide resins, imide resins, PVC (polyvinyl chloride) resins, PVB (polyvinyl butyral) resins, and EVA (ethylene vinyl acetate) resins. Materials with low moisture permeability, such as epoxy resins, are particularly preferred. Two-component mixed resins may also be used. Adhesive sheets may also be used. 【0226】 The display device 1000 is a top-emission type. The light emitted by the light-emitting device is emitted towards the substrate 110. Therefore, it is preferable to use a material with high transparency to visible light for the substrate 110. For example, the substrate 110 can be selected from among substrates that can be applied to substrate BS and have high transparency to visible light. The pixel electrodes contain a material that reflects visible light, and the counter electrodes (common electrodes 115) contain a material that transmits visible light. 【0227】 It should be noted that the display device according to one aspect of the present invention is not limited to the configuration of the display device 1000 shown in Figure 6. The display device according to one aspect of the present invention may be a modified configuration of the display device 1000 shown in Figure 6. 【0228】 For example, a light-shielding layer may be provided on the surface of the substrate 110 facing the substrate 310. This light-shielding layer can be provided between adjacent light-emitting devices and at the connection portion 140. Various optical components can also be arranged on the outer surface of the substrate 110. Examples of optical components include polarizing plates, phase difference plates, light diffusion layers (such as diffusion films), anti-reflective layers, and light-collecting films. Furthermore, surface protection layers such as an antistatic film to suppress the adhesion of dust, a water-repellent film to make it difficult for dirt to adhere, a hard coat film to suppress the occurrence of scratches during use, and an impact absorption layer may be arranged on the outside of the substrate 110. For example, a glass layer or a silica layer (SiO2) may be used as the surface protection layer. x By providing a protective layer, surface contamination and scratching can be suppressed, which is preferable. Furthermore, as a surface protective layer, DLC (diamond-like carbon), aluminum oxide (AlO2) x ), polyester-based materials, or polycarbonate-based materials may be used. It is preferable to use a material with high transmittance to visible light for the surface protective layer. Furthermore, it is preferable to use a material with high hardness for the surface protective layer. 【0229】 Furthermore, for example, as shown in the display device 1000A in Figure 8, the display device 1000 in Figure 6 may be provided with a panel having a touch sensor function (sometimes called a touch panel). In the display device 1000A in Figure 8, a resin layer 147, an insulator 103, a conductor 104, an insulator 105, and a conductor 106 are formed in order on the protective layer 131. 【0230】 The resin layer 147 preferably contains an organic insulating material. Examples of organic insulating materials include acrylic resin, polyimide resin, epoxy resin, polyamide resin, polyimidoamide resin, siloxane resin, benzocyclobutene resin, phenol resin, or precursors of these resins. 【0231】 The insulator 103 preferably contains an inorganic insulating material. Examples of inorganic insulating materials include oxides or nitrides such as silicon oxide, silicon oxide nitride, silicon oxide nitride, silicon nitride, aluminum oxide, aluminum oxide nitride, or hafnium oxide. 【0232】 Conductors 104 and 106 function as electrodes for a touch sensor. When using a mutual capacitance method as the touch sensor, for example, a pulse potential may be applied to one of the conductors 104 and 106, and an analog-to-digital (AD) conversion circuit or a detection circuit such as a sense amplifier may be connected to the other. In this case, a capacitance is formed between conductor 104 and conductor 106. When a finger or other object approaches, the magnitude of the capacitance changes (specifically, the capacitance decreases). This change in capacitance is expressed as a change in the amplitude of the signal generated on the other conductor when a pulse potential is applied to one of the conductors 104 and 106. This makes it possible to detect contact and proximity of a finger or other object. 【0233】 The insulator 105 can be an inorganic insulating film or an organic insulating film. Examples include resins such as acrylic resin and epoxy resin, and inorganic insulating materials such as silicon oxide, silicon oxide nitride, silicon nitride, silicon oxide, and aluminum oxide. The insulator 105 may be a single layer or a laminated structure. 【0234】 Furthermore, for example, the protective layer 131 of the display device 1000 in Figure 6 may be a laminated structure of two or more layers, rather than a single layer. The protective layer 131 may be a three-layer laminated structure, for example, with an inorganic insulating material as the first layer, an organic insulating material as the second layer, and an inorganic insulating material as the third layer. Figure 9 shows a cross-sectional view of a part of the display device 1000B in which the protective layer 131, including protective layers 131a, 131b, and 131c, is a multilayer structure, with protective layer 131a being an inorganic insulating material, protective layer 131b being an organic insulating material, and protective layer 131c being an inorganic insulating material. As shown in Figure 9, by applying an organic insulating material to protective layer 131b, the protective layer 131b can be provided as a planarized film. 【0235】 Furthermore, for example, the display device 1000 in Figure 6 may include a colored layer (color filter). As an example, the display device 1000C in Figure 10 shows a configuration in which a colored layer 166a, a colored layer 166b, and a colored layer 166c are included between the adhesive layer 107 and the substrate 110. The colored layers 166a to 166c can be formed on the substrate 110, for example. Also, if the light-emitting device 130R has a light-emitting layer that emits red (R) light, the light-emitting device 130G has a light-emitting layer that emits green (G) light, and the light-emitting device 130B has a light-emitting layer that emits blue (B) light, then the colored layer 166a is red, the colored layer 166b is green, and the colored layer 166c is blue. 【0236】 The display device according to one aspect of the present invention is not limited to the configuration of the display device 1000 shown in Figure 6. The configuration of the display device according to one aspect of the present invention may be modified as appropriate. 【0237】 For example, the display device may have a layer structure in which three or more transistors are stacked, rather than a layer structure in which two transistors are stacked (not shown). 【0238】 <Example of light-emitting device configuration> Next, we will describe an example configuration of a light-emitting device that can be applied to the display device described above. 【0239】 As shown in Figure 11A, the light-emitting device has an EL layer 763 between a pair of electrodes (lower electrode 761 and upper electrode 762). The EL layer 763 can be composed of multiple layers, such as layer 780, light-emitting layer 771, and layer 790. 【0240】 The light-emitting layer 771 has at least a light-emitting substance (also called a light-emitting material). 【0241】 When the lower electrode 761 is the anode and the upper electrode 762 is the cathode, layer 780 has one or more of the following: a layer containing a material with high hole injection properties (hole injection layer), a layer containing a material with high hole transport properties (hole transport layer), and a layer containing a material with high electron blocking properties (electron blocking layer). Similarly, layer 790 has one or more of the following: a layer containing a material with high electron injection properties (electron injection layer), a layer containing a material with high electron transport properties (electron transport layer), and a layer containing a material with high hole blocking properties (hole blocking layer). When the lower electrode 761 is the cathode and the upper electrode 762 is the anode, layers 780 and 790 have the opposite configurations to those described above. 【0242】 A configuration having a layer 780, an emissive layer 771, and a layer 790 provided between a pair of electrodes can function as a single emissive unit, and in this specification, the configuration shown in Figure 11A is referred to as a single structure. 【0243】 Furthermore, Figure 11B shows a modified example of the EL layer 763 of the light-emitting device shown in Figure 11A. Specifically, the light-emitting device shown in Figure 11B includes a layer 781 on the lower electrode 761, a layer 782 on the layer 781, a light-emitting layer 771 on the layer 782, a layer 791 on the light-emitting layer 771, a layer 792 on the layer 791, and an upper electrode 762 on the layer 792. 【0244】 When the lower electrode 761 is the anode and the upper electrode 762 is the cathode, for example, layer 781 can be a hole injection layer, layer 782 a hole transport layer, layer 791 an electron transport layer, and layer 792 an electron injection layer. Also, when the lower electrode 761 is the cathode and the upper electrode 762 is the anode, layer 781 can be an electron injection layer, layer 782 an electron transport layer, layer 791 a hole transport layer, and layer 792 a hole injection layer. By using such a layer structure, carriers can be efficiently injected into the light-emitting layer 771, and the efficiency of carrier recombination within the light-emitting layer 771 can be increased. 【0245】 As shown in Figures 11C and 11D, a configuration in which multiple light-emitting layers (light-emitting layer 771, light-emitting layer 772, and light-emitting layer 773) are provided between layer 780 and layer 790 is also a variation of the single structure. Although Figures 11C and 11D show an example with three light-emitting layers, the number of light-emitting layers in a single-structure light-emitting device may be two or four or more. Furthermore, a single-structure light-emitting device may have a buffer layer between the two light-emitting layers. 【0246】 Furthermore, as shown in Figures 11E and 11F, a configuration in which multiple light-emitting units (light-emitting units 763a and 763b) are connected in series via a charge generation layer 785 (also called an intermediate layer) is referred to as a tandem structure in this specification. The tandem structure may also be called a stacked structure. By using a tandem structure, a light-emitting device capable of high-brightness emission can be created. In addition, compared to a single structure, the tandem structure can reduce the current required to obtain the same brightness, thereby improving reliability. 【0247】 Figures 11D and 11F show examples where the display device has a layer 764 that overlaps with the light-emitting device. Figure 11D shows an example where layer 764 overlaps with the light-emitting device shown in Figure 11C, and Figure 11F shows an example where layer 764 overlaps with the light-emitting device shown in Figure 11E. 【0248】 Layer 764 can be either a color conversion layer or a color filter (coloring layer), or both. 【0249】 In Figures 11C and 11D, the light-emitting layers 771, 772, and 773 may be made of light-emitting materials that emit light of the same color, or even the same light-emitting material. For example, light-emitting materials that emit blue light may be used for the light-emitting layers 771, 772, and 773. In subpixels that emit blue light, the blue light emitted by the light-emitting device can be extracted. In subpixels that emit red light and subpixels that emit green light, a color conversion layer is provided as layer 764 as shown in Figure 11D, which converts the blue light emitted by the light-emitting device into longer wavelength light, allowing for the extraction of red or green light. 【0250】 Furthermore, light-emitting materials that emit light of different colors may be used for each of the light-emitting layers 771, 772, and 773. When the light emitted by each of the light-emitting layers 771, 772, and 773 is complementary in color, white light emission is obtained. For example, a single-structure light-emitting device preferably has a light-emitting layer having a light-emitting material that emits blue light, and a light-emitting layer having a light-emitting material that emits visible light with a longer wavelength than blue. 【0251】 For example, if a single-structure light-emitting device has three light-emitting layers, it is preferable that it has a light-emitting layer having a light-emitting material that emits red (R) light, a light-emitting layer having a light-emitting material that emits green (G) light, and a light-emitting layer having a light-emitting material that emits blue (B) light. The stacking order of the light-emitting layers can be, for example, R, G, B from the anode side, or R, B, G from the anode side. In this case, a buffer layer may be provided between R and G or B. 【0252】 Furthermore, for example, when a single-structure light-emitting device has two light-emitting layers, a configuration is preferred in which one light-emitting layer has a light-emitting material that emits blue (B) light, and the other light-emitting layer has a light-emitting material that emits yellow (Y) light. This configuration may be referred to as a BY single structure. 【0253】 A color filter may be provided as layer 764, as shown in Figure 11D. By passing white light through the color filter, light of the desired color can be obtained. 【0254】 A light-emitting device that emits white light preferably contains two or more types of light-emitting materials. To obtain white light emission, two light-emitting materials should be selected such that the light emitted by each material is complementary in color. For example, by making the light-emitting color of the first light-emitting layer and the light-emitting color of the second light-emitting layer complementary, a light-emitting device that emits white light as a whole can be obtained. Also, when obtaining white light emission using three or more light-emitting layers, the light-emitting device should be configured so that the light-emitting colors of the three or more layers combine to emit white light as a whole. 【0255】 Furthermore, in Figures 11E and 11F, the light-emitting layer 771 and the light-emitting layer 772 may be made of light-emitting materials that emit light of the same color, or even the same light-emitting material. 【0256】 For example, in a light-emitting device having subpixels that emit light of each color, light-emitting materials that emit blue light may be used in the light-emitting layer 771 and the light-emitting layer 772, respectively. In the subpixels that emit blue light, the blue light emitted by the light-emitting device can be extracted. In addition, in the subpixels that emit red light and the subpixels that emit green light, a color conversion layer is provided as layer 764 as shown in Figure 11F, which converts the blue light emitted by the light-emitting device into longer wavelength light, allowing red or green light to be extracted. 【0257】 Furthermore, when using light-emitting devices with the configuration shown in Figure 11E or Figure 11F for sub-pixels that emit light of each color, different light-emitting materials may be used for each sub-pixel. Specifically, in a light-emitting device for a sub-pixel that emits red light, light-emitting materials that emit red light may be used for both the light-emitting layer 771 and the light-emitting layer 772. Similarly, in a light-emitting device for a sub-pixel that emits green light, light-emitting materials that emit green light may be used for both the light-emitting layer 771 and the light-emitting layer 772. In a light-emitting device for a sub-pixel that emits blue light, light-emitting materials that emit blue light may be used for both the light-emitting layer 771 and the light-emitting layer 772. A display device with such a configuration can be said to have a tandem structure light-emitting device and an SBS structure. Therefore, it can combine the advantages of both the tandem structure and the SBS structure. This enables high-brightness light emission and realizes a highly reliable display device. 【0258】 Furthermore, in Figures 11E and 11F, luminescent materials emitting light of different colors may be used for the luminescent layer 771 and the luminescent layer 772. When the light emitted by the luminescent layer 771 and the light emitted by the luminescent layer 772 are complementary colors, white light emission is obtained. A color filter may be provided as layer 764 as shown in Figure 11F. By passing white light through the color filter, light of a desired color can be obtained. 【0259】 In Figures 11E and 11F, examples are shown in which the light-emitting unit 763a has one light-emitting layer 771 and the light-emitting unit 763b has one light-emitting layer 772, but the design is not limited to this. The light-emitting units 763a and 763b may each have two or more light-emitting layers. 【0260】 Furthermore, while Figures 11E and 11F illustrate a light-emitting device having two light-emitting units, the device is not limited to this. A light-emitting device may have three or more light-emitting units. 【0261】 Specifically, the configuration of the light-emitting device shown in Figures 12A to 12C is an example. 【0262】 Fig. 12A shows a configuration having three light-emitting units. The configuration having two light-emitting units may be referred to as a two-stage tandem structure, and the configuration having three light-emitting units may be referred to as a three-stage tandem structure, respectively. 【0263】 Also, as shown in Fig. 12A, a plurality of light-emitting units (light-emitting unit 763a, light-emitting unit 763b, and light-emitting unit 763c) are connected in series via charge generation layers (charge generation layer 785a-b and charge generation layer 785b-c). Specifically, the light-emitting device shown in Fig. 12A has a configuration in which the light-emitting unit 763a, the charge generation layer 785a-b, the light-emitting unit 763b, the charge generation layer 785b-c, and the light-emitting unit 763c are laminated in this order. Further, the light-emitting unit 763a has the layer 780a, the light-emitting layer 771, and the layer 790a, the light-emitting unit 763b has the layer 780b, the light-emitting layer 772, and the layer 790b, and the light-emitting unit 763c has the layer 780c, the light-emitting layer 773, and the layer 790c. 【0264】 For the charge generation layer 785a-b and the charge generation layer 785b-c, refer to the description of the charge generation layer 785 described above. 【0265】 In the configuration shown in FIG. 12A, it is preferable that the light-emitting layer 771, the light-emitting layer 772, and the light-emitting layer 773 each have a light-emitting substance that emits light of the same color. Specifically, the light-emitting layer 771, the light-emitting layer 772, and the light-emitting layer 773 may each have a light-emitting substance that emits red (R) light (so-called R\R\R three-stage tandem structure), the light-emitting layer 771, the light-emitting layer 772, and the light-emitting layer 773 may each have a light-emitting substance that emits green (G) light (so-called G\G\G three-stage tandem structure), or the light-emitting layer 771, the light-emitting layer 772, and the light-emitting layer 773 may each have a light-emitting substance that emits blue (B) light (so-called B\B\B three-stage tandem structure). In the configuration shown in FIG. 12A, each of the light-emitting layer 771, the light-emitting layer 772, and the light-emitting layer 773 may have a light-emitting substance that emits a different color from each other. Further, the configuration shown in FIG. 12A may be a configuration in which the colors of the light emitted by each of the light-emitting layer 771, the light-emitting layer 772, and the light-emitting layer 773 are combined to form white (W). Also, in the configuration shown in FIG. 12A, a layer 764 may be provided as a color filter in the same manner as in FIG. 12D or FIG. 12F. 【0266】 Note that the light-emitting substance that emits light of the same color is not limited to the above configuration. For example, as shown in FIG. 12B, a tandem-type light-emitting device in which light-emitting units having a plurality of light-emitting substances are stacked may be used. FIG. 12B shows a configuration in which a plurality of light-emitting units (light-emitting unit 763a and light-emitting unit 763b) are connected in series via a charge generation layer 785. The light-emitting unit 763a has a layer 780a, a light-emitting layer 771a, a light-emitting layer 771b, and a light-emitting layer 771c, and a layer 790a, and the light-emitting unit 763b has a layer 780b, a light-emitting layer 772a, a light-emitting layer 772b, and a light-emitting layer 772c, and a layer 790b. 【0267】 In the configuration shown in Figure 12B, the light-emitting layers 771a, 771b, and 771c are configured to emit white light (W) when the colors emitted by each layer are combined. Similarly, the light-emitting layers 772a, 772b, and 772c are configured to emit white light (W) when the colors emitted by each layer are combined. In other words, the configuration shown in Figure 12C is a two-stage tandem structure of W\W. There are no particular restrictions on the stacking order of the light-emitting layers 771a, 771b, and 771c. Likewise, there are no particular restrictions on the stacking order of the light-emitting layers 772a, 772b, and 772c. The implementer can select the optimal stacking order as appropriate. In addition, although not shown, a three-stage tandem structure of W\W\W or a tandem structure of four or more stages may also be used. 【0268】 Furthermore, when using a tandem light-emitting device, there are two-stage tandem structures B\Y having a light-emitting unit that emits yellow (Y) light and a light-emitting unit that emits blue (B) light, two-stage tandem structures RG\B having a light-emitting unit that emits red (R) and green (G) light and a light-emitting unit that emits blue (B) light, and a light-emitting unit that emits blue (B) light. Examples include a B\Y\B three-stage tandem structure having a light-emitting unit that emits blue (B) light, a light-emitting unit that emits yellow-green (YG) light, and a light-emitting unit that emits blue (B) light in that order, and a B\YG\B three-stage tandem structure having a light-emitting unit that emits blue (B) light, a light-emitting unit that emits green (G) light, and a light-emitting unit that emits blue (B) light in that order. 【0269】 Furthermore, as shown in Figure 12C, a combination of a light-emitting unit having one light-emitting material and a light-emitting unit having multiple light-emitting materials may be used. 【0270】 Specifically, in the configuration shown in Figure 12C, multiple light-emitting units (light-emitting units 763a, 763b, and 763c) are connected in series via charge generation layers (charge generation layers 785a-b and 785b-c). Light-emitting unit 763a has layer 780a, light-emitting layer 771, and layer 790a; light-emitting unit 763b has layer 780b, light-emitting layer 772a, light-emitting layer 772b, light-emitting layer 772c, and layer 790b; and light-emitting unit 763c has layer 780c, light-emitting layer 773, and layer 790c. 【0271】 For example, in the configuration shown in Figure 12C, a three-stage tandem structure of B\R·G·YG\B can be applied, where light-emitting unit 763a is a light-emitting unit that emits blue (B) light, light-emitting unit 763b is a light-emitting unit that emits red (R), green (G), and yellow-green (YG) light, and light-emitting unit 763c is a light-emitting unit that emits blue (B) light. 【0272】 For example, the number of layers and color order of the light-emitting unit can be, from the anode side, a two-layer structure of B and Y, a two-layer structure of B and light-emitting unit X, a three-layer structure of B, Y and B, or a three-layer structure of B, X and B. The number of layers and color order of the light-emitting layers in light-emitting unit X can be, from the anode side, a two-layer structure of R and Y, a two-layer structure of R and G, a two-layer structure of G and R, a three-layer structure of G, R and G, or a three-layer structure of R, G and R. In addition, other layers may be provided between the two light-emitting layers. 【0273】 Furthermore, in Figures 11C and 11D, as shown in Figure 11B, layer 780 and layer 790 may each be independently constructed as a laminated structure consisting of two or more layers. 【0274】 Furthermore, in Figures 11E and 11F, the light-emitting unit 763a has layer 780a, light-emitting layer 771, and layer 790a, and the light-emitting unit 763b has layer 780b, light-emitting layer 772, and layer 790b. 【0275】 When the lower electrode 761 is the anode and the upper electrode 762 is the cathode, layers 780a and 780b each have one or more of the following: a hole injection layer, a hole transport layer, and an electron blocking layer. Similarly, layers 790a and 790b each have one or more of the following: an electron injection layer, an electron transport layer, and a hole blocking layer. When the lower electrode 761 is the cathode and the upper electrode 762 is the anode, layers 780a and 790a have the opposite configurations to those described above, and layers 780b and 790b also have the opposite configurations to those described above. 【0276】 When the lower electrode 761 is the anode and the upper electrode 762 is the cathode, for example, layer 780a has a hole injection layer and a hole transport layer on the hole injection layer, and may further have an electron blocking layer on the hole transport layer. Also, layer 790a has an electron transport layer and may further have a hole blocking layer between the light-emitting layer 771 and the electron transport layer. Also, layer 780b has a hole transport layer and may further have an electron blocking layer on the hole transport layer. Also, layer 790b has an electron transport layer and an electron injection layer on the electron transport layer, and may further have a hole blocking layer between the light-emitting layer 772 and the electron transport layer. When the lower electrode 761 is the cathode and the upper electrode 762 is the anode, for example, layer 780a has an electron injection layer and an electron transport layer on the electron injection layer, and may further have a hole blocking layer on the electron transport layer. Furthermore, layer 790a may have a hole transport layer and an electron blocking layer between the light-emitting layer 771 and the hole transport layer. Also, layer 780b may have an electron transport layer and an electron blocking layer on the electron transport layer. Furthermore, layer 790b may have a hole transport layer and a hole injection layer on the hole transport layer, and an electron blocking layer between the light-emitting layer 772 and the hole transport layer. 【0277】 Furthermore, when fabricating a tandem light-emitting device, the two light-emitting units are stacked with a charge generation layer 785 in between. The charge generation layer 785 has at least a charge generation region. The charge generation layer 785 has the function of injecting electrons into one of the two light-emitting units and holes into the other when a voltage is applied between the pair of electrodes. 【0278】 Next, we will describe materials that can be used in light-emitting devices. 【0279】 Of the lower electrode 761 and upper electrode 762, the electrode that extracts light preferably uses a conductive film that transmits visible light. Furthermore, it is preferable to use a conductive film that reflects visible light on the electrode that does not extract light. In addition, if the display device has a light-emitting device that emits infrared light, it is preferable to use a conductive film that transmits both visible light and infrared light on the electrode that extracts light, and a conductive film that reflects both visible light and infrared light on the electrode that does not extract light. 【0280】 Furthermore, a conductive film that transmits visible light may also be used on the electrode that does not extract light. In this case, it is preferable to place the electrode between the reflective layer and the EL layer 763. In other words, the light emitted from the EL layer 763 may be reflected by the reflective layer and extracted from the display device. 【0281】 As the material for forming the pair of electrodes of the light-emitting device, metals, alloys, electrically conductive compounds, and mixtures thereof can be used as appropriate. Specifically, such materials include aluminum, titanium, chromium, manganese, iron, cobalt, nickel, copper, gallium, zinc, indium, tin, molybdenum, tantalum, tungsten, palladium, gold, platinum, silver, yttrium, or neodymium. Alternatively, such materials include alloys containing the above-mentioned metals in appropriate combinations. Alternatively, such materials include indium tin oxide (In-Sn oxide, also called ITO), In-Si-Sn oxide (also called ITSO), indium zinc oxide (In-Zn oxide), and In-W-Zn oxide. Furthermore, such materials include aluminum-containing alloys (aluminum alloys) such as aluminum, nickel, and lanthanum alloys (Al-Ni-La), and silver, palladium, and copper alloys (Ag-Pd-Cu, also written as APC). Other materials include elements belonging to Group 1 or Group 2 of the periodic table not exemplified above (for example, lithium, cesium, calcium, or strontium), rare earth metals such as europium and ytterbium, alloys containing these in appropriate combinations, graphene, and the like. 【0282】 It is preferable that the light-emitting device has a microcavity structure. Therefore, it is preferable that one of the pair of electrodes in the light-emitting device has an electrode that is transparent to and reflective to visible light (a semi-transmissive / semi-reflective electrode), and the other has an electrode that is reflective to visible light (a reflective electrode). By having a microcavity structure in the light-emitting device, the light emitted from the light-emitting layer can be resonated between the two electrodes, thereby strengthening the light emitted from the light-emitting device. 【0283】 Furthermore, the semi-transparent / semi-reflective electrode can have a laminated structure consisting of a conductive layer that can be used as a reflective electrode and a conductive layer that can be used as an electrode that transmits visible light (also called a transparent electrode). 【0284】 The light transmittance of the transparent electrode shall be 40% or more. For example, for the transparent electrode of the light-emitting device, it is preferable to use an electrode with a visible light (light with a wavelength of 400 nm or more and less than 750 nm) transmittance of 40% or more. The reflectance of visible light of the semi-transmissive / semi-reflective electrode shall be 10% or more and 95% or less, preferably 30% or more and 80% or less. The reflectance of visible light of the reflective electrode shall be 40% or more and 100% or less, preferably 70% or more and 100% or less. Also, the resistivity of these electrodes is preferably 1×10 -2 Ω·cm or less. 【0285】 The light-emitting device has at least a light-emitting layer. Also, the light-emitting device may further have, as layers other than the light-emitting layer, a layer containing a substance with high hole injection property, a substance with high hole transport property, a hole-blocking material, a substance with high electron transport property, an electron-blocking material, a substance with high electron injection property, or a bipolar substance (a substance with high electron transport property and high hole transport property), etc. For example, the light-emitting device can be configured to have one or more layers selected from a hole injection layer, a hole transport layer, a hole-blocking layer, a charge generation layer, an electron-blocking layer, an electron transport layer, and an electron injection layer in addition to the light-emitting layer. 【0286】 Either a low-molecular compound or a high-molecular compound can be used for the light-emitting device, and it may contain an inorganic compound. The layers constituting the light-emitting device can be formed by methods such as a vapor deposition method (including a vacuum vapor deposition method), a transfer method, a printing method, an inkjet method, a coating method, etc. 【0287】 The light-emitting layer has one or more light-emitting substances. As the light-emitting substance, a substance that exhibits a light-emitting color such as blue, purple, blue-violet, green, yellow-green, yellow, orange, or red is appropriately used. Also, a substance that emits near-infrared light can be used as the light-emitting substance. 【0288】 Examples of the light-emitting substance include a fluorescent material, a phosphorescent material, a TADF material, or a quantum dot material. 【0289】 Examples of fluorescent materials include pyrene derivatives, anthracene derivatives, triphenylene derivatives, fluorene derivatives, carbazole derivatives, dibenzothiophene derivatives, dibenzofuran derivatives, dibenzoquinoxaline derivatives, quinoxaline derivatives, pyridine derivatives, pyrimidine derivatives, phenanthrene derivatives, or naphthalene derivatives. 【0290】 Examples of phosphorescent materials include organometallic complexes (especially iridium complexes) having a 4H-triazole skeleton, a 1H-triazole skeleton, an imidazole skeleton, a pyrimidine skeleton, a pyrazine skeleton, or a pyridine skeleton; organometallic complexes (especially iridium complexes) using a phenylpyridine derivative having an electron-withdrawing group as a ligand; platinum complexes; or rare earth metal complexes. 【0291】 The light-emitting layer may contain one or more types of organic compounds (host material, assist material, etc.) in addition to the light-emitting substance (guest material). One or more types of organic compounds may include materials with high hole transport properties (hole transport materials) and / or materials with high electron transport properties (electron transport materials). As the hole transport material, a material with high hole transport properties that can be used in the hole transport layer described later may be used. As the electron transport material, a material with high electron transport properties that can be used in the electron transport layer, as described later, may be used. Furthermore, one or more types of organic compounds may include bipolar materials or TADF materials. 【0292】 The light-emitting layer preferably comprises, for example, a phosphorescent material and a combination of a hole-transporting material and an electron-transporting material that readily forms an excitation complex. This configuration allows for efficient emission using ExTET (Exciplex-Triplet Energy Transfer), which is energy transfer from the excitation complex to the light-emitting substance (phosphorescent material). By selecting a combination that forms an excitation complex that exhibits emission overlapping with the wavelength of the lowest-energy absorption band of the light-emitting substance, energy transfer becomes smoother, and light emission can be obtained efficiently. This configuration simultaneously achieves high efficiency, low-voltage operation, and a long lifespan for the light-emitting device. 【0293】 The hole injection layer is a layer that injects holes from the anode into the hole transport layer, and is a layer containing a material with high hole injection capabilities. Examples of materials with high hole injection capabilities include aromatic amine compounds and composite materials containing hole transport materials and acceptor materials (electron-accepting materials). 【0294】 As the hole-transporting material, a material with high hole-transporting properties that can be used in the hole-transporting layer, as described later, can be used. 【0295】 As acceptor materials, for example, oxides of metals belonging to groups 4 through 8 of the periodic table can be used. Specifically, these include molybdenum oxide, vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, tungsten oxide, manganese oxide, and rhenium oxide. Among these, molybdenum oxide is particularly preferred because it is stable in the atmosphere, has low hygroscopicity, and is easy to handle. Organic acceptor materials containing fluorine can also be used. Furthermore, organic acceptor materials such as quinodimethane derivatives, chloranil derivatives, and hexaazatriphenylene derivatives can also be used. 【0296】 For example, as a material with high hole injection properties, a material containing a hole transport material and an oxide of a metal belonging to Group 4 to Group 8 of the periodic table (typically molybdenum oxide) may be used. 【0297】 The hole transport layer is a layer that transports holes injected from the anode by the hole injection layer to the light-emitting layer. The hole transport layer is a layer containing a hole-transporting material. The hole-transporting material is 1 × 10⁻¹⁶ -6 cm 2 Materials having a hole mobility of / Vs or higher are preferred. However, other materials can also be used as long as they have higher hole transport capabilities than electron transport. Preferred hole transport materials include π-electron-rich heteroaromatic compounds (e.g., carbazole derivatives, thiophene derivatives, furan derivatives, etc.) or aromatic amines (compounds having an aromatic amine skeleton) which have high hole transport capabilities. 【0298】 The electron blocking layer is provided in contact with the light-emitting layer. The electron blocking layer is a layer containing a material that has hole-transporting properties and is capable of blocking electrons. Among the hole-transporting materials mentioned above, a material that has electron-blocking properties can be used for the electron blocking layer. 【0299】 Because electron-blocking layers possess hole-transporting properties, they can also be called hole-transporting layers. Furthermore, among hole-transporting layers, those that exhibit electron-blocking properties can also be called electron-blocking layers. 【0300】 The electron transport layer is a layer that transports electrons injected from the cathode by the electron injection layer to the light-emitting layer. The electron transport layer is a layer containing an electron-transporting material. The electron-transporting material is 1 × 10⁻¹⁶ -6 cm 2Materials having an electron mobility of / Vs or higher are preferred. However, other materials can also be used as long as they have higher electron transport capabilities than holes. Examples of electron-transporting 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, as well as oxadiazole derivatives, triazole derivatives, imidazole derivatives, oxazole derivatives, thiazole derivatives, phenanthroline derivatives, quinoline derivatives having a quinoline ligand, benzoquinoline derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, and other π-electron-deficient heteroaromatic compounds containing nitrogen-containing heteroaromatic compounds. 【0301】 The hole-blocking layer is provided in contact with the light-emitting layer. The hole-blocking layer is a layer containing a material that has electron-transporting properties and is capable of blocking holes. Among the electron-transporting materials mentioned above, a material that has hole-blocking properties can be used for the hole-blocking layer. 【0302】 Because hole-blocking layers possess electron-transporting properties, they can also be called electron-transporting layers. Furthermore, among electron-transporting layers, those that exhibit hole-blocking properties can also be called hole-blocking layers. 【0303】 The electron injection layer is a layer that injects electrons from the cathode to the electron transport layer, and is a layer containing a material with high electron injection capabilities. Alkali metals, alkaline earth metals, or compounds thereof can be used as materials with high electron injection capabilities. Composite materials containing both electron transport materials and donor materials (electron-donating materials) can also be used as materials with high electron injection capabilities. 【0304】 Furthermore, it is preferable that the lowest unoccupied molecular orbital (LUMO) level of a material with high electron injection potential has a small difference (specifically, 0.5 eV or less) from the work function value of the material used as the cathode. 【0305】 The electron injection layer contains, for example, lithium, cesium, ytterbium, lithium fluoride (LiF), cesium fluoride (CsF), and calcium fluoride (CaF). x , x is any number), 8-(quinolinolato)lithium (abbreviation: Liq), 2-(2-pyridyl)phenolatritium (abbreviation: LiPP), 2-(2-pyridyl)-3-pyridinolatritium (abbreviation: LiPPy), 4-phenyl-2-(2-pyridyl)phenolatritium (abbreviation: LiPPP), lithium oxide (LiO x Alkali metals such as cesium carbonate, alkaline earth metals, or compounds thereof can be used. The electron injection layer may also be a multilayer structure of two or more layers. For example, a multilayer structure in which lithium fluoride is used as the first layer and ytterbium is provided as the second layer can be used. 【0306】 The electron injection layer may contain an electron transport material. For example, a compound having a lone pair of electrons and an electron-deficient heteroaromatic ring can be used as the electron transport material. Specifically, a compound having one or more selected from a pyridine ring, a diazine ring (e.g., a pyrimidine ring, a pyrazine ring, or a pyridazine ring), or a triazine ring can be used. 【0307】 Furthermore, the LUMO level of organic compounds containing lone pairs of electrons is preferably between -3.6 eV and -2.3 eV. In general, the highest occupied molecular orbital (HOMO) level and the LUMO level of organic compounds can be estimated by cyclic voltammetry (CV), photoelectron spectroscopy, optical absorption spectroscopy, or inverse photoelectron spectroscopy. 【0308】 For example, 4,7-diphenyl-1,10-phenanthroline (abbreviated as BPhen), 2,9-di(naphthalene-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviated as NBPhen), diquinoxalino[2,3-a:2',3'-c]phenazine (abbreviated as HATNA), or 2,4,6-tris[3'-(pyridine-3-yl)biphenyl-3-yl]-1,3,5-triazine (abbreviated as TmPPPyTz) can be used in organic compounds containing lone pairs of electrons. NBPhen has a higher glass transition temperature (Tg) and superior heat resistance compared to BPhen. 【0309】 As described above, the charge generation layer has at least a charge generation region. The charge generation region preferably contains an acceptor material, and preferably contains, for example, a hole transport material and an acceptor material applicable to the hole injection layer described above. 【0310】 Furthermore, the charge generation layer preferably includes a layer containing a material with high electron injection potential. This layer can also be called an electron injection buffer layer. The electron injection buffer layer is preferably provided between the charge generation region and the electron transport layer. By providing an electron injection buffer layer, the injection barrier between the charge generation region and the electron transport layer can be relaxed, allowing electrons generated in the charge generation region to be easily injected into the electron transport layer. 【0311】 The electron injection buffer layer preferably contains an alkali metal or an alkaline earth metal, and can, for example, be configured to contain an alkali metal compound or an alkaline earth metal compound. Specifically, the electron injection buffer layer preferably has an inorganic compound containing an alkali metal and oxygen, or an inorganic compound containing an alkaline earth metal and oxygen, and more preferably has an inorganic compound containing lithium and oxygen (for example, lithium oxide (Li2O)). In addition, any material applicable to the electron injection layer described above can be suitably used for the electron injection buffer layer. 【0312】 The charge generation layer preferably has a layer containing a material with high electron transport properties. This layer can also be called an electron relay layer. The electron relay layer is preferably provided between the charge generation region and the electron injection buffer layer. If the charge generation layer does not have an electron injection buffer layer, the electron relay layer is preferably provided between the charge generation region and the electron transport layer. The electron relay layer has the function of preventing interaction between the charge generation region and the electron injection buffer layer (or electron transport layer) and smoothly transferring electrons. 【0313】 As the electron relay layer, it is preferable to use a phthalocyanine-based material such as copper(II) phthalocyanine (abbreviated as CuPc), or a metal complex having a metal-oxygen bond and an aromatic ligand. 【0314】 Furthermore, the charge generation region, electron injection buffer layer, and electron relay layer described above may not be clearly distinguishable depending on their cross-sectional shape or characteristics. 【0315】 The charge generation layer may have a donor material instead of an acceptor material. For example, the charge generation layer may have a layer containing an electron transport material and a donor material, which is applicable to the electron injection layer described above. 【0316】 When stacking light-emitting units, the rise in driving voltage can be suppressed by providing a charge generation layer between the two light-emitting units. 【0317】 <Example of pixel circuit configuration> Here, we will describe an example of a pixel circuit configuration that can be provided in the pixel layer PXAL. 【0318】 Figures 13A and 13B show examples of pixel circuit configurations that can be provided in the pixel layer PXAL, and light-emitting devices 130 connected to the pixel circuit. Figure 13A shows the connections of each circuit element included in the pixel circuit 400 provided in the pixel layer PXAL, and Figure 13B schematically shows the hierarchical relationship between the circuit layer SICL, which includes the drive circuit 30, the layer OSL, which includes multiple transistors of the pixel circuit, and the layer EML, which includes the light-emitting device 130. The pixel layer PXAL of the display device 1000 shown in Figure 13B includes, as an example, the layer OSL and the layer EML. Transistors 200A, 200B, and 200C included in the layer OSL shown in Figure 13B correspond to transistor 200 in Figure 6. The light-emitting device 130 included in the layer EML shown in Figure 13B corresponds to light-emitting device 130R, light-emitting device 130G, or light-emitting device 130B in Figure 6. 【0319】 The pixel circuit 400 shown as an example in Figures 13A and 13B comprises transistors 200A, 200B, 200C, and capacitor 600. Transistors 200A, 200B, and 200C can be transistors applicable to the transistor 200 described above, for example. That is, transistors 200A, 200B, and 200C can be LTPS transistors. Alternatively, transistors 200A, 200B, and 200C can be transistors applicable to the transistor 200 described above, for example. That is, transistors 200A, 200B, and 200C can be OS transistors. In particular, when transistors 200A, 200B, and 200C are OS transistors, it is preferable that each of transistors 200A, 200B, and 200C is equipped with a back gate electrode. In this case, the back gate electrode can be configured to receive the same signal as the gate electrode, or to receive a different signal from the gate electrode. Although Figures 13A and 13B show back gate electrodes for transistors 200A, 200B, and 200C, transistors 200A, 200B, and 200C may be configured without back gate electrodes. 【0320】 Transistor 200B comprises a gate electrode electrically connected to transistor 200A, a first electrode electrically connected to light-emitting device 130, and a second electrode electrically connected to wiring ANO. Wiring ANO is a wire that provides a potential for supplying current to light-emitting device 130. 【0321】 Transistor 200A comprises a first terminal electrically connected to the gate electrode of transistor 200B, a second terminal electrically connected to wiring SL which functions as a source line, and a gate electrode that has the function of controlling a conduction state or a non-conduction state based on the potential of wiring GL1 which functions as a gate line. 【0322】 Transistor 200C comprises a first terminal electrically connected to wiring V0, a ​​second terminal electrically connected to the light-emitting device 130, and a gate electrode that has the function of controlling a conduction state or a non-conduction state based on the potential of wiring GL2 which functions as a gate wire. Wiring V0 is a wiring for supplying a reference potential and a wiring for outputting the current flowing through the pixel circuit 400 to the drive circuit 30. 【0323】 Capacitor 600 comprises a conductive film electrically connected to the gate electrode of transistor 200B and a conductive film electrically connected to the second electrode of transistor 200C. 【0324】 The light-emitting device 130 includes a first electrode electrically connected to the first electrode of the transistor 200B, and a second electrode electrically connected to the wiring VCOM. The wiring VCOM is a wire that provides a potential for supplying current to the light-emitting device 130. 【0325】 This allows the intensity of light emitted by the light-emitting device 130 to be controlled according to the image signal applied to the gate electrode of transistor 200B. Furthermore, variations in the gate-source voltage of transistor 200B can be suppressed by the reference potential of the wiring V0 provided via transistor 200C. 【0326】 Furthermore, the wiring V0 can output a current value that can be used to set pixel parameters. More specifically, wiring V0 can function as a monitor line for outputting the current flowing through transistor 200B or the current flowing through light-emitting device 130 to the outside. The current output to 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 AD converter or the like and output to an AI accelerator or the like included in the external control circuit PRPH described in the above embodiment. 【0327】 In the configuration shown as an example in Figure 13B, the wiring electrically connecting the pixel circuit 400 and the drive circuit 30 can be shortened, thereby reducing the wiring resistance. As a result, data can be written at high speed, and the display device 1000 can be driven at high speed. This allows for a sufficient frame duration even with a large number of pixel circuits 400 in the display device 1000, thus increasing the pixel density of the display device 1000. Furthermore, increasing the pixel density of the display device 1000 improves the resolution of the image displayed by the display device 1000. For example, the pixel density of the display device 1000 can be set to 500 ppi or more, preferably 1000 ppi or more. Therefore, the display device 1000 can be used as a display device for AR or VR, and can be suitably applied to electronic devices where the distance between the display unit and the user is close, such as HMDs. 【0328】 Although Figures 13A and 13B show a pixel circuit 400 having a total of three transistors as an example, the pixel circuit relating to one embodiment of the present invention is not limited to this. Below, examples of pixel circuit configurations applicable to the pixel circuit 400 will be described. 【0329】 The pixel circuit 400A shown in Figure 14A illustrates transistors 200A and 200B, and capacitor 600. Figure 14A also illustrates the light-emitting device 130 connected to the pixel circuit 400A. Furthermore, wirings SL, GL, ANO, and VCOM are electrically connected to the pixel circuit 400A. 【0330】 Transistor 200A's gate is electrically connected to wiring GL, and one of its source and drain is electrically connected to wiring SL, the other of which is connected to the gate of transistor 200B and one of the electrodes of capacitor 600. Transistor 200B's source and drain are electrically connected to wiring ANO, and the other of which is connected to the anode of light-emitting device 130. Capacitor 600's other electrode is electrically connected to the anode of light-emitting device 130. Light-emitting device 130's cathode is electrically connected to wiring VCOM. 【0331】 The pixel circuit 400B shown in Figure 14B is a configuration in which transistor 200C is added to the pixel circuit 400A. Furthermore, wiring V0 is electrically connected to the pixel circuit 400B. 【0332】 The pixel circuit 400C shown in Figure 14C is an example in which transistors 200A and 200B of the pixel circuit 400A are replaced with transistors in which the gate and back gate are electrically connected. Similarly, the pixel circuit 400D shown in Figure 14D is an example in which the same transistor is applied to the pixel circuit 400B. This increases the current that the transistor can supply. Here, all transistors are shown as having a pair of electrically connected gates, but this is not the only option. Alternatively, transistors with a pair of gates that are electrically connected to different wirings may be used. For example, reliability can be improved by using a transistor in which one of the gates and the source are electrically connected. 【0333】 The pixel circuit 400E shown in Figure 15A is a configuration in which transistor 200D is added to the above-mentioned pixel circuit 400B. In addition, three wires (wires GL1, GL2, and GL3) that function as gate wires are electrically connected to the pixel circuit 400E. 【0334】 Transistor 200D has its gate electrically connected to wiring GL3, and one of its source and drain is electrically connected to the gate of transistor 200B, while the other is electrically connected to wiring V0. Also, the gate of transistor 200A is electrically connected to wiring GL1, and the gate of transistor 200C is electrically connected to wiring GL2. 【0335】 By simultaneously making transistors 200C and 200D conduct, the source and gate of transistor 200B become at the same potential, making transistor 200B non-conductive. This allows the current flowing to the light-emitting device 130 to be forcibly interrupted. Such a pixel circuit is suitable for display methods that alternate between display periods and off periods. 【0336】 The pixel circuit 400F shown in Figure 15B is an example of adding a capacitance of 600A to the above pixel circuit 400E. The capacitance of 600A functions as a holding capacitance. 【0337】 The pixel circuit 400G shown in Figure 15C and the pixel circuit 400H shown in Figure 15D are examples of applying transistors with electrically connected gates to the above-mentioned pixel circuit 400E or pixel circuit 400F, respectively. Transistors 200A, 200C, and 200D are transistors with electrically connected gates and back gates, while transistor 200B is a transistor with its gate electrically connected to its source. 【0338】 <Pixel layout> This section describes pixel layout. There are no particular limitations on the arrangement of subpixels, and various methods can be applied. Examples of subpixel arrangements include stripe arrangements, S-stripe arrangements, matrix arrangements, delta arrangements, Bayer arrangements, or pentile arrangements. 【0339】 Furthermore, the top surface shape of the sub-pixel can be, for example, a polygon such as a triangle, quadrilateral (e.g., rectangle or square), or pentagon, or a polygon with rounded corners, or an ellipse or a circle. Here, the top surface shape of the sub-pixel corresponds to the top surface shape of the light-emitting region of the light-emitting device. 【0340】 A stripe array is applied to pixel 80 shown in Figure 16A. Pixel 80 shown in Figure 16A is composed of three subpixels: subpixel 80a, subpixel 80b, and subpixel 80c. For example, as shown in Figure 17A, subpixel 80a may be a red subpixel R, subpixel 80b a green subpixel G, and subpixel 80c a blue subpixel B. 【0341】 The pixel 80 shown in Figure 16B has an S-stripe array applied to it. The pixel 80 shown in Figure 16B is composed of three subpixels: subpixel 80a, subpixel 80b, and subpixel 80c. For example, as shown in Figure 17B, subpixel 80a may be a blue subpixel B, subpixel 80b may be a red subpixel R, and subpixel 80c may be a green subpixel G. 【0342】 Figure 16C shows an example where the subpixels of each color are arranged in a zigzag pattern. Specifically, in a plan view, the upper edges of two subpixels aligned in the column direction (for example, subpixels 80a and 80b, or subpixels 80b and 80c) are offset. For example, as shown in Figure 17C, subpixel 80a may be the red subpixel R, subpixel 80b may be the green subpixel G, and subpixel 80c may be the blue subpixel B. 【0343】 The pixel 80 shown in Figure 16D has a sub-pixel 80a with a roughly trapezoidal top surface shape with rounded corners, a sub-pixel 80b with a roughly triangular top surface shape with rounded corners, and a sub-pixel 80c with a roughly square or roughly hexagonal top surface shape with rounded corners. Furthermore, sub-pixel 80a has a larger light-emitting area than sub-pixel 80b. Thus, the shape and size of each sub-pixel can be determined independently. For example, the size of a sub-pixel can be reduced to a level that provides a more reliable light-emitting device. For example, as shown in Figure 17D, sub-pixel 80a may be a green sub-pixel G, sub-pixel 80b may be a red sub-pixel R, and sub-pixel 80c may be a blue sub-pixel B. 【0344】 A Pentile array is applied to pixels 70A and 70B shown in Figure 16E. Figure 16E shows an example in which pixels 70A having subpixels 80a and 80b and pixels 70B having subpixels 80b and 80c are arranged alternately. For example, as shown in Figure 17E, 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. 【0345】 Pixels 70A and 70B, shown in Figures 16F and 16G, utilize a delta array. Pixel 70A has two subpixels (subpixels 80a and 80b) in the top row (1st row) and one subpixel (subpixel 80c) in the bottom row (2nd row). Pixel 70B has one subpixel (subpixel 80c) in the top row (1st row) and two subpixels (subpixels 80a and 80b) in the bottom row (2nd row). For example, as shown in Figure 17F, subpixel 80a may be a red subpixel R, subpixel 80b a green subpixel G, and subpixel 80c a blue subpixel B. 【0346】 Figure 16F shows an example where each subpixel has a roughly square top shape with rounded corners, and Figure 16G shows an example where each subpixel has a circular top shape. 【0347】 In photolithography, the finer the pattern being processed, the more significant the effects of light diffraction become. This compromises the fidelity of the pattern transfer to the photomask through exposure, making it difficult to process the resist mask into the desired shape. Therefore, even if the photomask pattern is rectangular, patterns with rounded corners are likely to form. Consequently, the top surface shape of subpixels may be a polygon with rounded corners, an ellipse, or a circle. 【0348】 Furthermore, in a method for manufacturing a display device according to one aspect 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 EL layer material and the curing temperature of the resist material, the curing of the resist film may be insufficient. A resist film that is not sufficiently cured may take 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, if an attempt is made to form a resist mask with a square top surface, a resist mask with a circular top surface may be formed, resulting in a circular top surface shape for the EL layer. 【0349】 Furthermore, in order to achieve the desired shape of the upper surface of the EL layer, a technique (OPC (Optical Proximity Correction) technique) may be used to pre-correct the mask pattern so that the design pattern and the transferred pattern match. Specifically, in the OPC technique, a correction pattern is added to the corners of the shape on the mask pattern. 【0350】 The pixels 80 shown in Figures 18A to 18C have a stripe arrangement applied to them. 【0351】 Figure 18A shows an example where each subpixel has a rectangular top surface shape, Figure 18B shows an example where each subpixel has a top surface shape formed by connecting two semicircles and a rectangle, and Figure 18C shows an example where each subpixel has an elliptical top surface shape. 【0352】 Pixel 80, shown in Figures 18D to 18F, has a matrix array applied to it. 【0353】 Figure 18D shows an example where each subpixel has a square top surface shape, Figure 18E shows an example where each subpixel has a roughly square top surface shape with rounded corners, and Figure 18F shows an example where each subpixel has a circular top surface shape. 【0354】 The pixel 80 shown in Figures 18A to 18F is composed of four subpixels: subpixel 80a, subpixel 80b, subpixel 80c, and subpixel 80d. Each of the subpixels 80a, 80b, 80c, and 80d emits light of a different color. For example, subpixels 80a, 80b, 80c, and 80d can be red, green, blue, and white subpixels, respectively. For example, as shown in Figures 19A and 19B, subpixels 80a, 80b, 80c, and 80d can be red, green, blue, and white subpixels, respectively. Alternatively, subpixels 80a, 80b, 80c, and 80d can be red, green, blue, and infrared emitting subpixels, respectively. 【0355】 The sub-pixel 80d has a light-emitting device. This light-emitting device includes, for example, a pixel electrode, an EL layer, and a common electrode. The pixel electrode may be made of the same material as conductors 112a to 112c, or conductors 126a to 126c. The EL layer may be made of the same material as, for example, the first layer 113a, the second layer 113b, or the third layer 113c. 【0356】 Figure 18G shows an example where one pixel 80 is composed of two rows and three columns. Pixel 80 has three subpixels (subpixels 80a, 80b, and 80c) in the top row (1st row) and three subpixels 80d in the bottom row (2nd row). In other words, pixel 80 has subpixels 80a and 80d in the left column (1st column), subpixels 80b and 80d in the middle column (2nd column), and subpixels 80c and 80d in the right column (3rd column). As shown in Figure 18G, by aligning the arrangement of subpixels in the top and bottom rows, it becomes possible to efficiently remove dust and other debris that may occur during the manufacturing process. Therefore, a display device with high display quality can be provided. 【0357】 Figure 18H shows an example where a single pixel 80 is composed of 2 rows and 3 columns. Pixel 80 has three subpixels (subpixels 80a, 80b, and 80c) in the top row (row 1) and one subpixel (subpixel 80d) in the bottom row (row 2). In other words, pixel 80 has subpixel 80a in the left column (column 1), subpixel 80b in the middle column (column 2), subpixel 80c in the right column (column 3), and subpixel 80d across these three columns. 【0358】 Furthermore, in the pixel 80 shown in Figures 18G and 18H, for example, as shown in Figures 19C and 19D, sub-pixel 80a can be a red sub-pixel R, sub-pixel 80b can be a green sub-pixel G, sub-pixel 80c can be a blue sub-pixel B, and sub-pixel 80d can be a white sub-pixel W. 【0359】 Furthermore, the insulators, conductors, semiconductors, etc., disclosed in this specification can be formed by PVD (Physical Vapor Deposition) or CVD (Chemical Vapor Deposition) methods. Examples of PVD methods include sputtering, resistance heating deposition, electron beam deposition, 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). 【0360】 Thermal CVD (Chemical Vapor Deposition) is a film deposition method that does not use plasma, and therefore has the advantage of not generating defects due to plasma damage. 【0361】 In the thermal CVD method, the raw material gas and oxidizer may be simultaneously introduced into a chamber, the chamber pressure may be reduced to atmospheric pressure or reduced pressure, and the reaction may occur near or on the substrate, resulting in film deposition on the substrate. 【0362】 Furthermore, the ALD method may also be performed by maintaining atmospheric pressure or reduced pressure inside the chamber, sequentially introducing the raw material gases for the reaction into the chamber, and repeating the order of gas introduction. For example, two or more types of raw material gases may be supplied to the chamber sequentially by switching each switching valve (also called a high-speed valve), and an inert gas (e.g., argon or nitrogen) may be introduced simultaneously with or after the first raw material gas to prevent mixing of multiple raw material gases, followed by the introduction of the second raw material gas. When an inert gas is introduced simultaneously, the inert gas acts as a carrier gas, and an inert gas may also be introduced simultaneously with the introduction of the second raw material gas. Alternatively, instead of introducing an inert gas, the first raw material gas may be discharged by vacuum evacuation before introducing the second raw material gas. The first raw material gas adsorbs onto the surface of the substrate to form a first thin layer, which then reacts with the second raw material gas introduced later to laminate a second thin layer on top of the first thin layer, forming a thin film. By controlling the order of gas introduction and repeating this process multiple times until the desired thickness is achieved, a thin film with excellent step coverage can be formed. Since the thickness of the thin film can be adjusted by the number of times the gas introduction sequence is repeated, precise film thickness control is possible, making it suitable for fabricating fine FETs. 【0363】 Thermal CVD methods such as MOCVD or ALD can form various films, including metal films, semiconductor films, and inorganic insulating films, as disclosed in the embodiments described above. For example, when forming an In-Ga-Zn-O film, trimethylindium (In(CH3)3), trimethylgallium (Ga(CH3)3), and dimethylzinc (Zn(CH3)2) are used. However, the method is not limited to these combinations; triethylgallium (Ga(C2H5)3) can be used instead of trimethylgallium, and diethylzinc (Zn(C2H5)2) can be used instead of dimethylzinc. 【0364】 For example, when forming a hafnium oxide film using a film deposition apparatus that utilizes the ALD method, two types of gases are used: a raw material gas obtained by vaporizing a liquid containing a solvent and a hafnium precursor compound (for example, hafnium alkoxide or hafnium amide such as tetrakisdimethylamidehafnium (TDMAH, Hf[N(CH3)2]4)), and ozone (O3) as an oxidizing agent. Another example of a material is tetrakis(ethylmethylamide)hafnium. 【0365】 For example, when forming an aluminum oxide film using a film deposition apparatus that utilizes the ALD method, two types of gases are used: a raw material gas obtained by vaporizing a liquid containing a solvent and an aluminum precursor compound (e.g., trimethylaluminum (TMA, Al(CH3)3)) and H2O as an oxidizing agent. Other materials include tris(dimethylamide)aluminum, triisobutylaluminum, or aluminum tris(2,2,6,6-tetramethyl-3,5-heptanedionate). 【0366】 For example, when forming a silicon oxide film using a film deposition apparatus that utilizes the ALD method, hexachlorodisilane is adsorbed onto the film deposition surface, and radicals of an oxidizing gas (e.g., O2 or nitrous oxide) are supplied to react with the adsorbed material. 【0367】 For example, when depositing a tungsten film using a film deposition apparatus that utilizes the ALD method, an initial tungsten film is formed by sequentially introducing WF6 gas and B2H6 gas repeatedly, and then the tungsten film is formed by sequentially introducing WF6 gas and H2 gas repeatedly. Note that SiH4 gas may be used instead of B2H6 gas. 【0368】 For example, when depositing an In-Ga-Zn-O film as an oxide semiconductor film using a film deposition apparatus utilizing the ALD method, the film is formed by sequentially and repeatedly introducing a precursor (generally, sometimes called a precursor or metal precursor) and an oxidizing agent (generally, sometimes called a reactant or nonmetal precursor). Specifically, for example, an In-O layer is formed by introducing In(CH3)3 gas as a precursor and O3 gas as an oxidizing agent, then a GaO layer is formed by introducing Ga(CH3)3 gas as a precursor and O3 gas as an oxidizing agent, and then a ZnO layer is formed by introducing Zn(CH3)2 gas as a precursor and O3 gas as an oxidizing agent. Note that the order of these layers is not limited to this example. Furthermore, mixed oxide layers such as an In-Ga-O layer, an In-Zn-O layer, or a Ga-Zn-O layer may also be formed using these gases. Note that H2O gas obtained by bubbling water with an inert gas such as Ar may be used instead of O3 gas, but it is preferable to use O3 gas which does not contain H. Also, In(C2H5)3 gas may be used instead of In(CH3)3 gas. Also, Ga(C2H5)3 gas may be used instead of Ga(CH3)3 gas. Furthermore, Zn(CH3)2 gas may be used. 【0369】 Furthermore, there are no particular limitations on the aspect ratio of the display unit in the electronic device according to one embodiment of the present invention. For example, the display unit can support various aspect ratios such as 1:1 (square), 4:3, 16:9, or 16:10. 【0370】 Furthermore, the shape of the display unit in an electronic device according to one aspect of the present invention is not particularly limited. For example, the display unit can be rectangular, polygonal (e.g., octagonal), circular, elliptical, or various other shapes. 【0371】 This embodiment can be appropriately combined with other embodiments shown in this specification. 【0372】 (Embodiment 3) This embodiment describes metal oxides (hereinafter also referred to as oxide semiconductors) that can be used in the OS transistor described in the above embodiment. 【0373】 The metal oxide used in the OS transistor preferably contains at least indium or zinc, and more preferably indium and zinc. For example, the metal oxide preferably contains indium, M (where M is one or more selected from gallium, aluminum, yttrium, tin, silicon, boron, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, magnesium, and cobalt), and zinc. In particular, M is preferably one or more selected from gallium, aluminum, yttrium, and tin, and more preferably gallium. 【0374】 Metal oxides can be formed by chemical vapor deposition (CVD) methods such as sputtering, metal-organic chemical vapor deposition (MOCVD), or atomic layer deposition (ALD). 【0375】 In the following sections, we will describe oxides containing indium (In), gallium (Ga), and zinc (Zn) as examples of metal oxides. Note that oxides containing indium (In), gallium (Ga), and zinc (Zn) are sometimes called In-Ga-Zn oxides. 【0376】 <Classification of crystal structures> Examples of crystalline structures for oxide semiconductors include amorphous (including completely amorphous), CAAC (c-axis-aligned crystalline), nc (nanocrystalline), CAC (cloud-aligned composite), single crystal, and polycrystal. 【0377】 The crystal structure of a film or substrate can be evaluated using X-ray diffraction (XRD) spectroscopy. For example, it can be evaluated using the XRD spectrum obtained from a GIXD (Grazing-Incidence XRD) measurement. The GIXD method is also known as the thin-film method or the Seemann-Bohlin method. In the following text, the XRD spectrum obtained from a GIXD measurement may simply be referred to as the XRD spectrum. 【0378】 For example, in a quartz glass substrate, the peak shape of the XRD spectrum is nearly symmetrical. On the other hand, in an In-Ga-Zn oxide film with a crystalline structure, the peak shape of the XRD spectrum is asymmetrical. The asymmetrical shape of the XRD spectrum peaks clearly indicates the presence of crystals in the film or substrate. In other words, if the peak shape of the XRD spectrum is not symmetrical, the film or substrate cannot be said to be in an amorphous state. 【0379】 Furthermore, the crystalline structure of a film or substrate can be evaluated by the diffraction pattern (also called the nano-beam electron diffraction pattern) observed using nano-beam electron diffraction (NBED). For example, a halo is observed in the diffraction pattern of a quartz glass substrate, confirming that the quartz glass is in an amorphous state. On the other hand, a spot-like pattern is observed in the diffraction pattern of an In-Ga-Zn oxide film deposited at room temperature, rather than a halo. Therefore, it is presumed that the In-Ga-Zn oxide deposited at room temperature is in an intermediate state, neither single-crystal nor polycrystalline, nor amorphous, and cannot be concluded to be in an amorphous state. 【0380】 <<Oxide semiconductor structure>> It should be noted that oxide semiconductors may be classified differently from those described above when considering their structure. For example, oxide semiconductors can be divided into single-crystal oxide semiconductors and other non-single-crystal oxide semiconductors. Examples of non-single-crystal oxide semiconductors include the aforementioned CAAC-OS and nc-OS. Non-single-crystal oxide semiconductors also include polycrystalline oxide semiconductors, pseudo-amorphous oxide semiconductors (a-like OS), amorphous oxide semiconductors, etc. 【0381】 Here, we will explain the details of the CAAC-OS, nc-OS, and a-like OS mentioned above. 【0382】 [CAAC-OS] CAAC-OS is an oxide semiconductor having multiple crystalline regions, the c-axis of which is oriented in a specific direction. This specific direction is the thickness direction of the CAAC-OS film, the normal direction to the surface on which the CAAC-OS film is formed, or the normal direction to the surface of the CAAC-OS film. A crystalline region is a region with periodic atomic arrangement. If we consider the atomic arrangement as a lattice arrangement, then a crystalline region is also a region with a aligned lattice arrangement. Furthermore, CAAC-OS has regions where multiple crystalline regions are connected in the ab-plane direction, and these regions may exhibit distortion. Distortion refers to a point in the connected region where the orientation of the lattice arrangement changes between a region with a aligned lattice arrangement and another region with a aligned lattice arrangement. In short, CAAC-OS is an oxide semiconductor that is c-axis oriented and does not exhibit clear orientation in the ab-plane direction. 【0383】 Each of the above-mentioned crystalline regions is composed of one or more minute crystals (crystals with a maximum diameter of less than 10 nm). When a crystalline region is composed of one minute crystal, the maximum diameter of that crystalline region will be less than 10 nm. When a crystalline region is composed of many minute crystals, the maximum diameter of that crystalline region may be around several tens of nm. 【0384】 Furthermore, in In-Ga-Zn oxides, CAAC-OS tends to have a layered crystalline structure (also called a layered structure) consisting of layers containing indium (In) and oxygen (hereinafter referred to as the In layer) and layers containing gallium (Ga), zinc (Zn), and oxygen (hereinafter referred to as the (Ga,Zn) layer). Note that indium and gallium are mutually substitutable. Therefore, the (Ga,Zn) layer may contain indium. Also, the In layer may contain gallium. Also, the In layer may contain zinc. This layered structure can be observed, for example, as a lattice image in high-resolution TEM (Transmission Electron Microscope) images. 【0385】 When structural analysis of a CAAC-OS film is performed using an XRD instrument, for example, out-of-plane XRD measurements using θ / 2θ scanning show a peak indicating c-axis orientation at 2θ = 31° or nearby. Note that the position of the peak indicating c-axis orientation (value of 2θ) may vary depending on the type and composition of the metal elements constituting the CAAC-OS. 【0386】 Furthermore, for example, multiple bright spots are observed in the electron diffraction pattern of a CAAC-OS film. These spots are observed at point-symmetric positions with respect to the incident electron beam spot (also called the direct spot) that passed through the sample. 【0387】 When the crystal region is observed from the specific direction described above, the lattice arrangement within that crystal region is based on a hexagonal lattice, but the unit cell is not necessarily a regular hexagon and may be non-regular hexagonal. Furthermore, the strain may have lattice arrangements such as pentagons or heptagons. Moreover, in CAAC-OS, clear grain boundaries cannot be observed even near the strain. In other words, it can be seen that the formation of grain boundaries is suppressed by the strain in the lattice arrangement. This is thought to be because CAAC-OS can tolerate strain due to factors such as the non-dense arrangement of oxygen atoms in the ab-plane direction and the change in interatomic bond distances due to the substitution of metal atoms. 【0388】 Furthermore, a crystal structure in which clear grain boundaries can be observed is called a polycrystalline material. Grain boundaries act as recombination centers, trapping carriers and potentially causing a decrease in transistor on-current and field-effect mobility. Therefore, CAAC-OS, in which clear grain boundaries cannot be observed, is one of the crystalline oxides with a suitable crystal structure for the semiconductor layer of a transistor. In addition, a structure containing Zn is preferred for the composition of CAAC-OS. For example, In-Zn oxide and In-Ga-Zn oxide are preferred because they can suppress the generation of grain boundaries more effectively than In oxide. 【0389】 CAAC-OS is an oxide semiconductor with high crystallinity and no clearly defined grain boundaries. Therefore, CAAC-OS is less susceptible to the decrease in electron mobility caused by grain boundaries. Furthermore, since the crystallinity of oxide semiconductors can decrease due to the inclusion of impurities, the generation of defects, or both, CAAC-OS can be considered an oxide semiconductor with few impurities and defects (such as oxygen vacancies). Consequently, oxide semiconductors containing CAAC-OS have stable physical properties. Therefore, oxide semiconductors containing CAAC-OS are heat-resistant and highly reliable. In addition, CAAC-OS is stable even at high temperatures (so-called thermal budget) during the manufacturing process. Therefore, using CAAC-OS in OS transistors allows for greater flexibility in the manufacturing process. 【0390】 [nc-OS] nc-OS exhibits periodicity in atomic arrangement in minute regions (e.g., regions between 1 nm and 10 nm, particularly between 1 nm and 3 nm). In other words, nc-OS contains minute crystals. These minute crystals are also called nanocrystals because their size is, for example, between 1 nm and 10 nm, particularly between 1 nm and 3 nm. Furthermore, nc-OS shows no regularity in crystal orientation between different nanocrystals. Therefore, no orientation is observed throughout the film. Consequently, depending on the analytical method, nc-OS may be indistinguishable from a-like OS and amorphous oxide semiconductors. For example, when structural analysis of an nc-OS film is performed using an XRD instrument, no peaks indicating crystallinity are detected in out-of-plane XRD measurements using θ / 2θ scanning. Also, when electron diffraction (also called limited-field electron diffraction) is performed on an nc-OS film using an electron beam with a probe diameter larger than that of the nanocrystals (e.g., 50 nm or larger), a diffraction pattern resembling a halo pattern is observed. On the other hand, when electron diffraction (also called nanobeam electron diffraction) is performed on an nc-OS film using an electron beam with a probe diameter close to or smaller than the size of the nanocrystal (for example, 1 nm to 30 nm), an electron diffraction pattern may be obtained in which multiple spots are observed within a ring-shaped region centered on a direct spot. 【0391】 [a-like OS] a-like OS is an oxide semiconductor having a structure between nc-OS and amorphous oxide semiconductors. a-like OS has porous or low-density regions. In other words, a-like OS has lower crystallinity compared to nc-OS and CAAC-OS. Also, a-like OS has a higher hydrogen concentration in the film compared to nc-OS and CAAC-OS. 【0392】 <<Oxide Semiconductor Composition>> Next, we will explain the details of CAC-OS mentioned above. Note that CAC-OS refers to the material composition. 【0393】 [CAC-OS] CAC-OS is a material composition in which, for example, the elements constituting the metal oxide are unevenly distributed in sizes of 0.5 nm to 10 nm, preferably 1 nm to 3 nm, or close to that size. In the following, a state in which one or more metal elements are unevenly distributed in a metal oxide, and the regions containing these metal elements are mixed in sizes of 0.5 nm to 10 nm, preferably 1 nm to 3 nm, or close to that size, is also referred to as a mosaic or patchy state. 【0394】 Furthermore, CAC-OS is a composite metal oxide having a mosaic-like structure formed by the separation of the material into a first region and a second region, with the first region distributed within the film (hereinafter also referred to as a cloud-like structure). In other words, CAC-OS is a composite metal oxide having a structure in which the first region and the second region are mixed. 【0395】 Here, the atomic ratios of In, Ga, and Zn to the metal elements constituting the CAC-OS in In-Ga-Zn oxide are denoted as [In], [Ga], and [Zn], respectively. For example, in the CAC-OS of In-Ga-Zn oxide, the first region is the region where [In] is greater than the [In] in the composition of the CAC-OS film. The second region is the region where [Ga] is greater than the [Ga] in the composition of the CAC-OS film. Alternatively, for example, the first region is the region where [In] is greater than the [In] in the second region, and [Ga] is smaller than the [Ga] in the second region. The second region is the region where [Ga] is greater than the [Ga] in the first region, and [In] is smaller than the [In] in the first region. 【0396】 Specifically, the first region described above is a region whose main components are indium oxide, indium zinc oxide, etc. The second region described above is a region whose main components are gallium oxide, gallium zinc oxide, etc. In other words, the first region can be rephrased as a region whose main component is In. Similarly, the second region can be rephrased as a region whose main component is Ga. 【0397】 Furthermore, a clear boundary may not be observed between the first region and the second region described above. 【0398】 Furthermore, CAC-OS in In-Ga-Zn oxide refers to a material composition containing In, Ga, Zn, and O, in which regions with Ga as the main component and regions with In as the main component are arranged in a mosaic-like manner, with these regions existing randomly. Therefore, it is presumed that CAC-OS has a structure in which metal elements are unevenly distributed. 【0399】 CAC-OS can be formed, for example, by sputtering under conditions where the substrate is not heated. When forming CAC-OS by sputtering, one or more gases selected from inert gases (typically argon), oxygen gas, and nitrogen gas may be used as the deposition gas. Furthermore, a lower ratio of the oxygen gas flow rate to the total deposition gas flow rate during deposition is preferable. For example, the ratio of the oxygen gas flow rate to the total deposition gas flow rate during deposition should be 0% or more and less than 30%, preferably 0% or more and 10% or less. 【0400】 Furthermore, for example, in the case of CAC-OS in In-Ga-Zn oxide, EDX mapping obtained using energy dispersive X-ray spectroscopy (EDX) confirms that it has a structure in which regions mainly composed of In (first region) and regions mainly composed of Ga (second region) are unevenly distributed and mixed. 【0401】 Here, the first region is a region with higher conductivity compared to the second region. In other words, the conductivity of the metal oxide is exhibited when carriers flow through the first region. Therefore, a high field-effect mobility (μ) can be achieved when the first region is distributed in a cloud-like manner within the metal oxide. 【0402】 On the other hand, the second region is a region with higher insulating properties compared to the first region. In other words, the distribution of the second region within the metal oxide can suppress leakage current. 【0403】 Therefore, when CAC-OS is used in a transistor, the conductivity due to the first region and the insulation due to the second region work complementaryly to give CAC-OS a switching function (on / off function). In other words, CAC-OS has conductive function in part of the material, insulating function in part of the material, and semiconductor function as a whole. By separating the conductive function and the insulating function, both functions can be maximized. Therefore, by using CAC-OS in a transistor, a high on-current (I on This enables high field-effect mobility (μ) and good switching operation. 【0404】 Furthermore, transistors using CAC-OS offer high reliability. Therefore, CAC-OS is ideal for various semiconductor devices, including display devices. 【0405】 Oxide semiconductors can take on diverse structures, each possessing different properties. One embodiment of the present invention may include two or more of the following: amorphous oxide semiconductors, polycrystalline oxide semiconductors, a-like OS, CAC-OS, nc-OS, and CAAC-OS. 【0406】 <Transistors containing oxide semiconductors> Next, we will explain the case where the above oxide semiconductor is used in a transistor. 【0407】 By using the above-mentioned oxide semiconductor in transistors, it is possible to realize transistors with high field-effect mobility. Furthermore, it is possible to realize highly reliable transistors. 【0408】 In particular, it is preferable to use an oxide containing indium (In), gallium (Ga), and zinc (Zn) (also referred to as "IGZO") as the semiconductor layer in which the channel is formed. Alternatively, an oxide containing indium (In), aluminum (Al), and zinc (Zn) (also referred to as "IAZO") may be used as the semiconductor layer. Alternatively, an oxide containing indium (In), aluminum (Al), gallium (Ga), and zinc (Zn) (also referred to as "IAGZO") may be used as the semiconductor layer. 【0409】 It is preferable to use an oxide semiconductor with a low carrier concentration for the transistor. For example, the carrier concentration of an oxide semiconductor is 1 × 10⁻⁶. 17 cm -3 The following is preferably 1 × 10 15 cm -3 More preferably 1 × 10 13 cm -3 More preferably 1 × 10 11 cm -3 More preferably 1 × 10 10 cm -3 It is less than 1 × 10 -9 cm -3 This concludes the explanation. Furthermore, when lowering the carrier concentration of an oxide semiconductor film, the impurity concentration in the oxide semiconductor film should be lowered to reduce the defect level density. In this specification, a low impurity concentration and low defect level density are referred to as high-purity intrinsic or substantially high-purity intrinsic. Note that oxide semiconductors with low carrier concentrations are sometimes referred to as high-purity intrinsic or substantially high-purity intrinsic oxide semiconductors. 【0410】 High-purity intrinsic or substantially high-purity intrinsic oxide semiconductor films have a low defect level density, which may result in a low trap level density. 【0411】 Charges trapped in the trap levels of oxide semiconductors can take a long time to disappear and sometimes behave like fixed charges. Therefore, transistors in which channel formation regions are formed in oxide semiconductors with a high density of trap levels may exhibit unstable electrical properties. 【0412】 Therefore, reducing the impurity concentration in the oxide semiconductor is effective in stabilizing the electrical characteristics of the transistor. Furthermore, in order to reduce the impurity concentration in the oxide semiconductor, it is preferable to also reduce the impurity concentration in adjacent films. Examples of impurities include hydrogen, nitrogen, alkali metals, alkaline earth metals, iron, nickel, or silicon. Note that impurities in an oxide semiconductor refer to elements other than the main components that make up the oxide semiconductor. For example, elements with a concentration of less than 0.1 atomic percent can be considered impurities. 【0413】 <Impurities> Here, we will explain the effects of various impurities in oxide semiconductors. 【0414】 In oxide semiconductors, the presence of silicon or carbon, which are both Group 14 elements, leads to the formation of defect levels in the oxide semiconductor. Therefore, the concentration of silicon or carbon in the oxide semiconductor (the concentration obtained by secondary ion mass spectrometry (SIMS)) is 2 × 10⁻¹⁰. 18 atoms / cm 3 The following is preferably 2 × 10 17 atoms / cm 3 The following applies: 【0415】 When alkali metals or alkaline earth metals are present in oxide semiconductors, they can form defect levels and generate carriers. Therefore, transistors using oxide semiconductors containing alkali metals or alkaline earth metals tend to exhibit normally-on characteristics. For this reason, the concentration of alkali metals or alkaline earth metals in the oxide semiconductor obtained by SIMS should be set to 1 × 10⁻⁶. 18 atoms / cm 3 The following is preferably 2 × 10 16 atoms / cm 3 Do the following: 【0416】 In oxide semiconductors, the presence of nitrogen generates electrons, which act as carriers, increasing the carrier concentration and making it easier for the semiconductor to become n-type. As a result, transistors using oxide semiconductors containing nitrogen tend to exhibit normally-on characteristics. Alternatively, the presence of nitrogen in oxide semiconductors can lead to the formation of trap levels. This can result in unstable electrical properties of the transistor. Therefore, the nitrogen concentration in oxide semiconductors obtained by SIMS should be set to 5 × 10⁻¹⁰. 19 atoms / cm 3 Less than 5 × 10 18 atoms / cm 3 More preferably 1 × 10 18 atoms / cm 3 More preferably 5 × 10 17 atoms / cm 3 Do the following: 【0417】 Hydrogen contained in oxide semiconductors can react with oxygen bonded to metal atoms to form water, potentially creating oxygen vacancies. When hydrogen fills these vacancies, electrons, which act as carriers, can be generated. Furthermore, some of the hydrogen can combine with oxygen bonded to metal atoms to generate electrons. Therefore, transistors using oxide semiconductors containing hydrogen tend to exhibit normally-on characteristics. For this reason, it is preferable to reduce the hydrogen content in oxide semiconductors as much as possible. Specifically, the hydrogen concentration in the oxide semiconductor obtained by SIMS should be 1 × 10⁻⁶. 20 atoms / cm 3 Less than 1 × 10 19 atoms / cm 3 Less than 5x10 18 atoms / cm 3 Less than 1 × 10 18 atoms / cm 3 Make it less than. 【0418】 By using an oxide semiconductor with sufficiently reduced impurities in the channel formation region of a transistor, stable electrical characteristics can be provided. 【0419】 The configuration shown in this embodiment can be used in appropriate combination with the configurations shown in other embodiments. 【0420】 (Embodiment 4) This embodiment describes a display module applicable to an electronic device according to one aspect of the present invention. 【0421】 <Example of display module configuration> First, a display module equipped with a display device applicable to an electronic device according to one aspect of the present invention will be described. 【0422】 Figure 20A shows a perspective view of the display module 1280. The display module 1280 includes a display device 1000 and an FPC 1290. 【0423】 The display module 1280 has substrates 1291 and 1292. The display module 1280 has a display unit 1281. The display unit 1281 is an area in the display module 1280 that displays an image, and is an area in which light from each pixel provided in the pixel unit 1284, which will be described later, can be seen. 【0424】 Figure 20B shows a schematic perspective view illustrating the configuration of the substrate 1291. On the substrate 1291, a circuit section 1282, a pixel circuit section 1283 on the circuit section 1282, and a pixel section 1284 on the pixel circuit section 1283 are stacked. In addition, a terminal section 1285 for connecting to the FPC 1290 is provided in the portion of the substrate 1291 that does not overlap with the pixel section 1284. The terminal section 1285 and the circuit section 1282 are electrically connected by a wiring section 1286 composed of multiple wires. 【0425】 Furthermore, the pixel section 1284 and the pixel circuit section 1283 correspond to, for example, the pixel layer PXAL described above. Also, the circuit section 1282 corresponds to, for example, the circuit layer SICL described above. 【0426】 The pixel section 1284 has a plurality of periodically arranged pixels 1284a. A magnified view of a single pixel 1284a is shown on the right side of Figure 20B. Pixel 1284a has light-emitting devices 1430a, 1430b, and 1430c, each with a different emission color. Light-emitting devices 1430a, 1430b, and 1430c correspond, for example, to the aforementioned light-emitting devices 130R, 130G, and 130B. Furthermore, the plurality of light-emitting devices may be arranged in a stripe arrangement as shown in Figure 20B. Various arrangement methods such as delta arrangement and pentile arrangement can also be applied. 【0427】 The pixel circuit section 1283 has a plurality of pixel circuits 1283a arranged periodically. 【0428】 A single pixel circuit 1283a is a circuit that controls the light emission of three light-emitting devices in a single pixel 1284a. A single pixel circuit 1283a may also be configured to have three circuits that control the light emission of one light-emitting device. For example, a pixel circuit 1283a can be configured to have at least one selection transistor, one current control transistor (drive transistor), and a capacitor for each light-emitting device. In this case, a gate signal is input to the gate of the selection transistor, and a source signal is input to either the source or the drain. This realizes an active-matrix type display device. 【0429】 The circuit section 1282 has circuits for driving each pixel circuit 1283a of the pixel circuit section 1283. For example, it is preferable to have one or both of a gate line drive circuit and a source line drive circuit. In addition, it may have one or more selected from an arithmetic circuit, a memory circuit, a power supply circuit, etc. 【0430】 The FPC1290 functions as wiring for supplying video signals or power potential to the circuit unit 1282 from an external source. An IC may also be mounted on the FPC1290. 【0431】 Since the display module 1280 can be configured such that one or both of the pixel circuit section 1283 and the circuit section 1282 are stacked on the lower side of the pixel section 1284, the aperture ratio (effective display area ratio) of the display section 1281 can be made extremely high. 【0432】 This embodiment can be appropriately combined with other embodiments shown in this specification. 【0433】 (Embodiment 5) In this embodiment, an example of an electronic device to which a display device is applied will be described as an example of an electronic device according to one aspect of the present invention. 【0434】 Figures 21A and 21B show the external appearance of the electronic device 8300, which is a head-mounted display. 【0435】 The electronic device 8300 includes a housing 8301, a display unit 8302, operation buttons 8303, and a band-shaped fastener 8304. 【0436】 The operation button 8303 has functions such as a power button. The electronic device 8300 may also have other buttons besides the operation button 8303. 【0437】 Furthermore, as shown in Figure 21C, a lens 8305 may be provided between the display unit 8302 and the user's eye position. The lens 8305 allows the user to view the display unit 8302 in a magnified manner, thereby enhancing the sense of realism. In this case, as shown in Figure 21C, a dial 8306 may be provided to change the position of the lens for diopter adjustment. 【0438】 For the display unit 8302, it is preferable to use a display device with extremely high resolution. By using a display device with high resolution in the display unit 8302, even when magnified using the lens 8305 as shown in Figure 21C, the user will not be able to see the pixels, and a more realistic image can be displayed. 【0439】 Figures 21A to 21C show an example where there is one display unit 8302. This configuration allows for a reduction in the number of parts. 【0440】 The display unit 8302 can display two images side-by-side in its left and right regions, one for the right eye and the other for the left eye. This allows for the display of stereoscopic images using binocular parallax. 【0441】 Alternatively, a single image visible to both eyes may be displayed across the entire area of ​​the display unit 8302. This makes it possible to display a panoramic image across both ends of the field of view, thereby enhancing the sense of realism. 【0442】 Here, it is preferable that the electronic device 8300 has a mechanism to change the curvature of the display unit 8302 to an appropriate value according to the size of the user's head or the position of their eyes. For example, the user may adjust the curvature of the display unit 8302 themselves by operating a dial 8307 for adjusting the curvature of the display unit 8302. Alternatively, the housing 8301 may be provided with a sensor (e.g., a camera, a contact sensor, or a non-contact sensor) that detects the size of the user's head or the position of their eyes, and the device may have a mechanism to adjust the curvature of the display unit 8302 based on the sensor's detection data. 【0443】 Furthermore, when using lens 8305, it is preferable to provide a mechanism that adjusts the position and angle of lens 8305 in synchronization with the curvature of display unit 8302. Alternatively, dial 8306 may have a function to adjust the angle of the lens. 【0444】 Figures 21E and 21F show an example in which the curvature of the display unit 8302 is controlled by a drive unit 8308. The drive unit 8308 is fixed to at least a portion of the display unit 8302. The drive unit 8308 has the function of deforming the display unit 8302 by deforming or moving the portion to which it is fixed. 【0445】 Figure 21E is a schematic diagram showing a user 8310 with a relatively large head size wearing the housing 8301. In this case, the shape of the display unit 8302 is adjusted by the drive unit 8308 so that the curvature is relatively small (the radius of curvature is large). 【0446】 On the other hand, Figure 21F shows the case where user 8311, who has a smaller head size compared to user 8310, is wearing the housing 8301. Also, user 8311 has a narrower distance between their eyes compared to user 8310. In this case, the shape of the display unit 8302 is adjusted by the drive unit 8308 so that the curvature of the display unit 8302 is large (the radius of curvature is small). In Figure 21F, the position and shape of the display unit 8302 in Figure 21E are shown by dashed lines. 【0447】 Thus, by having a mechanism to adjust the curvature of the display unit 8302, the electronic device 8300 can provide an optimal display for a wide range of users, regardless of age or gender. 【0448】 Furthermore, by changing the curvature of the display unit 8302 according to the content displayed on it, a high level of realism can be provided to the user. For example, vibration can be simulated by vibrating the curvature of the display unit 8302. In this way, various effects can be applied to match the scenes in the content, providing the user with a new experience. Moreover, by linking this with the vibration module installed in the housing 8301, an even more immersive display becomes possible. 【0449】 The electronic device 8300 may also have two display units 8302, as shown in Figure 21D. 【0450】 Having two display units 8302 allows the user to view one display unit per eye. This enables the display of high-resolution images even when performing 3D displays using parallax. Furthermore, the display units 8302 are curved in an arc shape with the user's eye as the approximate center. This ensures that the distance from the user's eye to the display surface of the display unit remains constant, allowing the user to see a more natural image. In addition, even if the brightness and chromaticity of the light from the display unit change depending on the viewing angle, the user's eye is positioned in the direction of the normal to the display surface of the display unit, so this effect can be practically ignored, resulting in a more realistic image. 【0451】 Figures 22A to 22C show the appearance of an electronic device 8300 that differs from the electronic device 8300 shown in Figures 21A to 21D, respectively. Specifically, for example, Figures 22A to 22C differ from Figures 21A to 21D in that they have a fixing device 8304a for attachment to the head and a pair of lenses 8305. 【0452】 The user can view the display on the display unit 8302 through the lens 8305. It is preferable to position the display unit 8302 in a curved shape, as this allows the user to experience a greater sense of presence. Furthermore, by viewing different images displayed in different areas of the display unit 8302 through the lens 8305, three-dimensional display using parallax can be performed. Note that the configuration is not limited to a single display unit 8302; two display units 8302 may be provided, with one display unit for each of the user's eyes. 【0453】 Furthermore, it is preferable to use a display device with extremely high resolution for the display unit 8302. By using a display device with high resolution for the display unit 8302, even when magnified using the lens 8305 as shown in Figure 22C, the user will not be able to see the pixels, and a more realistic image can be displayed. 【0454】 Furthermore, a head-mounted display, which is an electronic device according to one aspect of the present invention, may be configured as an electronic device 8200, which is a glasses-type head-mounted display as shown in Figure 22D. 【0455】 The electronic device 8200 includes a mounting section 8201, a lens 8202, a main body 8203, a display unit 8204, and a cable 8205. A battery 8206 is also built into the mounting section 8201. 【0456】 Cable 8205 supplies power from battery 8206 to main unit 8203. Main unit 8203 is equipped with a wireless receiver and can display received video information on display unit 8204. In addition, main unit 8203 is equipped with a camera and can use information about the user's eyeball or eyelid movements as an input means. 【0457】 Furthermore, the attachment unit 8201 may be provided with multiple electrodes at a position that touches the user, capable of detecting the current flowing in accordance with the user's eye movements, and may have a function to recognize the user's gaze. It may also have a function to monitor the user's pulse rate based on the current flowing through the electrodes. In addition, the attachment unit 8201 may have various sensors such as a temperature sensor, a pressure sensor, or an acceleration sensor, and may have a function to display the user's biometric information on the display unit 8204, or a function to change the image displayed on the display unit 8204 in accordance with the user's head movements. 【0458】 Figures 23A to 23C show the external appearance of electronic device 8750, which is different from the electronic device 8300 shown in Figures 21A to 21D and Figures 22A to 22C, respectively, and the electronic device 8200 shown in Figure 22D. 【0459】 Figure 23A is a perspective view showing the front, top, and left side of the electronic device 8750, while Figures 23B and 23C are perspective views showing the rear, bottom, and right side of the electronic device 8750. 【0460】 The electronic device 8750 includes a pair of display devices 8751, a housing 8752, a pair of mounting parts 8754, a cushioning member 8755, a pair of lenses 8756, and the like. The pair of display devices 8751 are each provided inside the housing 8752 in a position where they can be seen through the lenses 8756. 【0461】 Here, one of the pair of display devices 8751 corresponds to the display device DSP described in Embodiment 1. Although not shown, the electronic device 8750 shown in Figures 23A to 23C has an electronic component with a processing unit described in the previous embodiment (for example, the circuit included in the control circuit PRPH shown in Figure 5). Although not shown, the electronic device 8750 shown in Figures 23A to 23C has a camera. This camera can capture images of the user's eyes and their vicinity. Although not shown, the electronic device 8750 shown in Figures 23A to 23C includes a motion detection unit, audio, control unit, communication unit, and battery within the housing 8752. 【0462】 The electronic device 8750 is an electronic device for VR. When a user wears the electronic device 8750, they can view images displayed on the display device 8751 through the lenses 8756. Furthermore, by displaying different images on a pair of display devices 8751, it is also possible to perform a three-dimensional display using parallax. 【0463】 Furthermore, the rear side of the housing 8752 is provided with an input terminal 8757 and an output terminal 8758. The input terminal 8757 can be connected to a cable that supplies video signals from a video output device or power to charge the battery provided inside the housing 8752. The output terminal 8758 functions, for example, as an audio output terminal, and earphones or headphones can be connected to it. 【0464】 Furthermore, it is preferable that the housing 8752 has a mechanism that allows adjustment of the left and right positions of the lens 8756 and the display device 8751 so that they are in the optimal position according to the position of the user's eyes. It is also preferable that the housing has a mechanism that adjusts the focus by changing the distance between the lens 8756 and the display device 8751. 【0465】 By using the above-mentioned camera, display device 8751, and electronic components, the electronic device 8750 can estimate the state of the user of the electronic device 8750 and display information regarding the estimated user state on the display device 8751. Alternatively, information regarding the user state of electronic devices connected to the electronic device 8750 via a network can be displayed on the display device 8751. 【0466】 The cushioning member 8755 is the part that comes into contact with the user's face (for example, the forehead or cheek). By ensuring that the cushioning member 8755 is in close contact with the user's face, light leakage can be prevented, thereby enhancing the sense of immersion. It is preferable to use a soft material for the cushioning member 8755 so that it comes into close contact with the user's face when the user wears the electronic device 8750. For example, materials such as rubber, silicone rubber, urethane, and sponge can be used. Furthermore, if the surface of a sponge or similar material is covered with cloth, leather (for example, genuine leather or synthetic leather), gaps are less likely to form between the user's face and the cushioning member 8755, effectively preventing light leakage. In addition, using such materials is preferable because it feels good against the skin and does not make the user feel cold when worn in cold seasons. It is preferable that the components that come into contact with the user's skin, such as the cushioning member 8755 or the mounting part 8754, be removable, as this makes cleaning or replacement easier. 【0467】 The electronic device of this embodiment may further include an earphone 8754A. The earphone 8754A has a communication unit (not shown) and has wireless communication functionality. The earphone 8754A can output audio data through its wireless communication functionality. The earphone 8754A may also have a vibration mechanism that functions as a bone conduction earphone. 【0468】 Furthermore, the earphone 8754A can be configured to be directly connected to the mounting part 8754 or connected via a wire, as shown in the earphone 8754B in Figure 23C. The earphone 8754B and the mounting part 8754 may also have magnets. This allows the earphone 8754B to be magnetically fixed to the mounting part 8754, which facilitates storage and is therefore preferable. 【0469】 The earphone 8754A may have a sensor unit. The state of the user of the electronic device can be estimated using this sensor unit. 【0470】 Furthermore, an electronic device according to one aspect of the present invention may have, in addition to any one of the above-described configuration examples, one or more selected from an antenna, a battery, a camera, a speaker, a microphone, a touch sensor, and an operation button. 【0471】 An electronic device according to one aspect of the present invention may have a secondary battery, and it is preferable that the secondary battery can be charged using contactless power transmission. 【0472】 Examples of secondary batteries include lithium-ion secondary batteries (for example, lithium polymer batteries using a gel-like electrolyte (lithium-ion polymer batteries)), nickel-metal hydride batteries, nickel-cadmium batteries, organic radical batteries, lead-acid batteries, air secondary batteries, nickel-zinc batteries, or silver-zinc batteries. 【0473】 An electronic device according to one aspect of the present invention may have an antenna. By receiving a signal with the antenna, the display unit can display images, information, etc. Furthermore, if the electronic device has an antenna and a secondary battery, the antenna may be used for contactless power transmission. 【0474】 The display unit of an electronic device according to one aspect of the present invention can display video having a screen resolution of, for example, Full HD, 4K2K, 8K4K, 16K8K, or higher. 【0475】 This embodiment can be appropriately combined with other embodiments shown in this specification. 【0476】 (Embodiment 6) This embodiment describes an electronic device equipped with a display device manufactured using one aspect of the present invention. 【0477】 The electronic device described below is equipped with a display device according to one embodiment of the present invention in its display unit. Therefore, it is an electronic device that achieves high screen resolution. 【0478】 For example, the display units of the notebook-type information terminal 5300 in Figure 24C, the television device 9000 in Figure 24F, the in-car display panels 5701 to 5704 in Figure 24G, and the electronic signboard 6200 in Figure 24H, which will be described later, may each use a display device of 12 inches or larger. For this reason, it is preferable to apply the display device described in Embodiment 1 to the electronic devices described above. This makes it possible to create electronic devices that have both high screen resolution and a large screen. 【0479】 Furthermore, the information terminal 5500 in Figure 24A, the information terminal 5900 in Figure 24B, the camera 8000 in Figure 24D, and the portable game console 5200 in Figure 24E, which will be described later, can each use a display device cut from a single circuit board on which multiple display devices are manufactured. This makes it possible to create electronic devices with high screen resolution. 【0480】 One aspect of the present invention comprises a display device and one or more components selected from an antenna, a battery, a housing, a camera, a speaker, a microphone, a touch sensor, and an operation button. 【0481】 An electronic device according to one aspect of the present invention may have a secondary battery as described in Embodiment 5. Furthermore, it is preferable that the secondary battery can be charged using contactless power transmission. 【0482】 Furthermore, for example, the secondary battery described in Embodiment 5 can be used. 【0483】 An electronic device according to one aspect of the present invention may have the antenna described in Embodiment 5. 【0484】 The display unit of an electronic device according to one aspect of the present invention can display video having a screen resolution of, for example, Full HD, 4K2K, 8K4K, 16K8K, or higher. 【0485】 Examples of electronic devices include those with relatively large screens, such as television sets, notebook computers, monitors, digital signage, pachinko machines, and game consoles. Examples of electronic devices with relatively small screens include digital cameras, digital video cameras, digital photo frames, mobile phones, portable game consoles, personal digital assistants, and audio playback devices. 【0486】 Electronic equipment to which one aspect of the present invention is applied can be incorporated along the interior or exterior surfaces (e.g., flat or curved surfaces) of buildings (e.g., residences, commercial facilities, and industrial facilities), or along the interior or exterior surfaces (e.g., flat or curved surfaces) of mobile bodies (e.g., automobiles, trains, ships, and aircraft). 【0487】 [mobile phone] The information terminal 5500 shown in Figure 24A is a type of information terminal, specifically a mobile phone (smartphone). The information terminal 5500 has a housing 5510 and a display unit 5511. For input interfaces, a touch panel is provided on the display unit 5511, and buttons are provided on the housing 5510. 【0488】 [Wearable devices] Figure 24B shows the external appearance of an information terminal 5900, which is an example of a wearable device. The information terminal 5900 has a housing 5901, a display unit 5902, operation buttons 5903, a crown 5904, and a band 5905. 【0489】 [Information terminal] Furthermore, Figure 24C illustrates a notebook-type information terminal 5300. As an example, the notebook-type information terminal 5300 shown in Figure 24C is equipped with a display unit 5331 in the casing 5330a and a keyboard unit 5350 in the casing 5330b. 【0490】 In the above, smartphones, wearable devices, and notebook computers were used as examples of electronic devices and illustrated in Figures 24A to 24C, respectively. However, other information terminals besides smartphones, wearable devices, and notebook computers can also be used. Examples of other information terminals besides smartphones, wearable devices, and notebook computers include PDAs (Personal Digital Assistants), desktop computers, and workstations. 【0491】 [camera] Figure 24D shows the external appearance of the camera 8000 with the viewfinder 8100 attached. 【0492】 The camera 8000 has a housing 8001, a display unit 8002, operation buttons 8003, and a shutter button 8004. The camera 8000 also has a detachable lens 8006 attached to it. 【0493】 Furthermore, the camera 8000 may have the lens 8006 and the housing integrated into a single unit. 【0494】 Camera 8000 can take an image by pressing the shutter button 8004 or by touching the display unit 8002, which functions as a touch panel. 【0495】 The housing 8001 has a mount with electrodes, and in addition to the viewfinder 8100, a strobe device and the like can be connected to it. 【0496】 The viewfinder 8100 has a housing 8101, a display unit 8102, and buttons 8103. 【0497】 The housing 8101 is attached to the camera 8000 by engaging with the camera's mount. The viewfinder 8100 can display the image received from the camera 8000 on the display unit 8102. 【0498】 Button 8103 functions as a power button. 【0499】 A display device according to one embodiment of the present invention can be applied to the display unit 8002 of the camera 8000 and the display unit 8102 of the viewfinder 8100. The camera 8000 may also have a built-in viewfinder. 【0500】 [Game console] Figure 24E shows the external appearance of a portable game console 5200, which is an example of a game console. The portable game console 5200 has a housing 5201, a display unit 5202, and buttons 5203. 【0501】 Furthermore, the video output from the portable game console 5200 can be displayed on display devices such as television equipment, personal computer displays, game displays, and head-mounted displays. 【0502】 By applying the display device described in the above embodiment to the portable game console 5200, a portable game console 5200 with low power consumption can be realized. Furthermore, because the low power consumption reduces heat generation from the circuit, the impact of heat on the circuit itself, peripheral circuits, and modules can be minimized. 【0503】 Figure 24E illustrates a portable game console as an example of a game console, but the electronic devices of one aspect of the present invention are not limited to this. Examples of electronic devices of one aspect of the present invention include a stationary game console, an arcade game machine installed in an entertainment facility (e.g., a game center or amusement park), and a pitching machine for batting practice installed in a sports facility. 【0504】 <Television equipment> Figure 24F is a perspective view showing a television device. The television device 9000 includes a housing 9002, a display unit 9001, a speaker 9003, operation keys 9005 (including a power switch or operation switches), connection terminals 9006, and sensors 9007 (including functions for measuring force, displacement, position, velocity, acceleration, angular velocity, rotational speed, distance, light, liquid, magnetism, temperature, chemical substances, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared radiation). A storage device according to one aspect of the present invention may be provided in the television device. The television device may incorporate a display unit 9001 of, for example, 50 inches or larger, or 100 inches or larger. 【0505】 By applying the display device described in the above embodiment to the television device 9000, a low-power television device 9000 can be realized. Furthermore, because the low power consumption reduces heat generation from the circuit, the impact of heat generation on the circuit itself, peripheral circuits, and modules can be minimized. 【0506】 <Mobile> A display device according to one aspect of the present invention can also be applied to the area around the driver's seat of a mobile vehicle. 【0507】 Figure 24G is a diagram showing the area around the windshield inside a car. In Figure 24G, display panels 5701, 5702, and 5703 mounted on the dashboard are shown, as well as display panel 5704 mounted on the pillar. 【0508】 Display panels 5701 to 5703 can provide various information by displaying, for example, navigation information, speedometer, tachometer, mileage, fuel gauge, gear status, and air conditioning settings. Furthermore, the display items and layout shown on the display panels can be changed as needed to suit the user's preferences, thereby enhancing the design. Display panels 5701 to 5703 can also be used as lighting devices. 【0509】 The display panel 5704 can compensate for the blind spots (views obstructed by the pillars) by displaying images from imaging devices installed on the vehicle body. In other words, by displaying images from imaging devices installed on the outside of the vehicle, blind spots can be compensated for, and safety can be enhanced. Furthermore, by displaying images that compensate for the parts that are not visible, safety checks can be performed more naturally and without discomfort. The display panel 5704 can also be used as a lighting device. 【0510】 A display device according to one aspect of the present invention can be applied, for example, to display panels 5701 to 5704. 【0511】 Although the above description uses automobiles as an example of a mobile body, the mobile body is not limited to automobiles. For example, other examples of mobile bodies include trains, monorails, ships, and aircraft (e.g., helicopters, unmanned aerial vehicles (drones), airplanes, or rockets), and a display device according to one aspect of the present invention can be applied to these mobile bodies. 【0512】 [Digital signboard] Figure 24H shows an example of a wall-mountable electronic sign (digital signage). Figure 24H shows the electronic sign 6200 mounted on wall 6201. A display device according to one aspect of the present invention can be applied, for example, to the display section of the electronic sign 6200. The electronic sign 6200 may also be provided with an interface such as a touch panel. 【0513】 While the above example shows an electronic device that can be mounted on a wall as an example of an electronic sign, the types of electronic signs are not limited to this. For example, electronic signs can be mounted on pillars, placed on the ground as a stand, or installed on the rooftops or side walls of buildings. 【0514】 This embodiment can be appropriately combined with other embodiments shown in this specification. [Explanation of symbols] 【0515】 DSP: display device, PXAL: pixel layer, EML: layer, OSL: layer, SICL: circuit layer, BS: substrate, DRV: drive circuit area, LIA: area, DIS: display section, ARA[1,1]: display area, ARA[2,1]: display area, ARA[m-1,1]: display area, ARA[m,1]: Display area, ARA[1,2]: Display area, ARA[2,2]: Display area, ARA[m-1,2]: Display area, ARA[m,2]: Display area, ARA[1,n-1]: Display area, ARA[2,n-1]: Display area, ARA[m-1,n-1]: Display area, ARA[m,n-1]: Table display area, ARA[1,n]: display area, ARA[2,n]: display area, ARA[m-1,n]: display area, ARA[m,n]: display area, ARD[1,1]: circuit area, ARD[2,1]: circuit area, ARD[m-1,1]: circuit area, ARD[m,1]: circuit area, ARD[ 1,2]: circuit area, ARD[2,2]: circuit area, ARD[m-1,2]: circuit area, ARD[m,2]: circuit area, ARD[1,n-1]: circuit area, ARD[2,n-1]: circuit area, ARD[m-1,n-1]: circuit area, ARD[m,n-1]: circuit area, ARD[1 ,n]: Circuit area, ARD[2,n]: Circuit area, ARD[m-1,n]: Circuit area, ARD[m,n]: Circuit area, PRPH: Control circuit, SD: Drive circuit, SDS: Circuit, GD: Drive circuit, GDS: Circuit, DMG: Distribution circuit, DMS: Distribution circuit, CTR: Control unit, MD: Memory device, PG: Voltage generation circuit, TMC: Timing controller, CKS: Clock signal generation circuit, GPS: Image processing unit, INT: Interface, BW: Bus wiring, PX: Pixel, GL: Wiring, GL1: Wiring, GL2: Wiring, GL3: Wiring, SL: Wiring, ANO: Wiring, VCOM :Wiring, V0:Wiring, 30:Drive circuit, 70A:Pixel, 70B:Pixel, 80:Pixel, 80a:Sub-pixel, 80b:Sub-pixel, 80c:Sub-pixel, 80d:Sub-pixel, 103:Insulator, 104:Conductor, 105:Insulator, 106:Conductor, 107:Adhesive layer, 110:Substrate, 112a:Conductor, 112b:Conductor, 112c:Conductor, 113a:First layer, 113b:Second layer, 113c:Third layer, 114:Common layer, 115:Common electrode, 118a:Mask layer, 125:Insulator, 127:Insulator, 126a:Conductor, 126b:Conductor, 126c:Conductor, 128:Layer,129a: Conductor, 129b: Conductor, 129c: Conductor, 130R: Light-emitting device, 130G: Light-emitting device, 130B: Light-emitting device, 131: Protective layer, 131a: Protective layer, 131b: Protective layer, 131c: Protective layer, 147: Resin layer, 166a: Colored layer, 166b: Colored layer, 166c: Colored layer, 200: Transistor, 200A: Transistor, 200B: Transistor, 200C: Transistor, 200D: Transistor, 211: Insulator, 213: Insulator, 214: Insulator, 215: Insulator, 218: Insulator, 221: Conductor, 222a: Conductor, 222b: Conductor, 223: Conductor, 225: Insulator, 231: Semiconductor layer, 231n: Low-resistance region, 231i: Channel formation region, 300: Transistor, 310: Substrate, 311: Insulator, 312: Insulator, 313: Insulator, 314: Insulator, 316: Conductor, 317: Conductor, 318: Semiconductor layer, 318i: Semiconductor region, 318p: Low-resistance region, 319: Conductor, 320: Insulator, 322: Insulator, 324: Insulator, 400: Pixel circuit, 400A: Pixel circuit, 400B: Pixel circuit, 400C: Pixel circuit, 400D: Pixel circuit, 400E: Pixel circuit, 40 0F: Pixel circuit, 400G: Pixel circuit, 400H: Pixel circuit, 600: Capacitance, 600A: Capacitance, 761: Lower electrode, 762: Upper electrode, 763: EL layer, 764: Layer, 771: Light-emitting layer, 771a: Light-emitting layer, 771b: Light-emitting layer, 771c: Light-emitting layer, 772: Light-emitting layer, 772a: Light-emitting layer, 772b: Light-emitting layer, 772c: Light-emitting layer, 773: Light-emitting layer, 780: Layer, 780a: Layer, 780b: Layer, 780c: Layer, 781: Layer, 782: Layer, 785: Charge generation layer, 790: Layer, 790a: Layer, 790b: Layer, 790c: Layer, 791: Layer, 792: Layer, 1000: Display unit 1000A: Display device, 1000B: Display device, 1000C: Display device, 1280: Display module, 1281: Display unit, 1290: FPC, 1282: Circuit unit, 1283: Pixel circuit unit, 1283a: Pixel circuit, 1284: Pixel unit, 1284a: Pixel, 1285: Terminal unit, 1286: Wiring unit, 1291: Board, 1292: Board, 1430a: Light-emitting device, 1430b: Light-emitting device, 1430c: Light-emitting device, 5200: Portable game console, 5201: Enclosure, 5202: Display unit, 5203: Button, 5300: Notebook-type information terminal, 5330a: Enclosure,5330b: Housing, 5331: Display unit, 5350: Keyboard unit, 5500: Information terminal, 5510: Housing, 5511: Display unit, 5701: Display panel, 5702: Display panel, 5703: Display panel, 5704: Display panel, 5900: Information terminal, 5901: Housing, 5902: Display unit, 5903: Operation buttons, 5904: Crown, 5905: Band, 6200: Electronic signboard, 6201: Wall, 8000: Camera, 8001: Housing, 8002: Display unit, 8003: Operation buttons, 8004: Shutter button, 8006: Lens, 8100: Viewfinder, 8101: Housing, 8102: Display unit, 8103: Button, 8200: Electronic equipment, 8201: Mounting unit, 8202 :Lens, 8203:Main unit, 8204:Display unit, 8205:Cable, 8206:Battery, 8300:Electronic equipment, 8301:Housing, 8302:Display unit, 8303:Operation buttons, 8304:Fixing device, 8304a:Fixing device, 8305:Lens, 8310:User, 8311:User, 8750:Electronic equipment, 8751:Display device, 8752:Housing, 8754:Mounting part, 8754A:Earphone, 8754B:Earphone, 8755:Cushioning material, 8756:Lens, 8757:Input terminal, 8758:Output terminal, 9000:Television device, 9001:Display unit, 9002:Housing, 9003:Speaker, 9005:Operation keys, 9006:Connection terminal, 9007:Sensor,

Claims

[Claim 1] It has a first layer and a second layer located above the first layer, The first layer comprises a substrate and a plurality of circuit regions. The second layer has multiple display areas, Each of the aforementioned plurality of circuit regions has a drive circuit, The drive circuit has a transistor containing low-temperature polysilicon in the channel formation region. Each of the plurality of display areas has a display pixel, The display pixel comprises a transistor containing a metal oxide in the channel formation region and a light-emitting device. The drive circuit included in one of the plurality of circuit regions has the function of driving the display pixel included in one of the plurality of display regions. At least two of the aforementioned plurality of display areas have a function to display images at different frame frequencies, The light-emitting device comprises: a first conductive film electrically connected to the transistor through an opening in a flat lower layer covering the transistor; an insulating layer disposed on a recess of the first conductive film in a region overlapping the opening; a second conductive film having a region in contact with the upper surface of the first conductive film, a region in contact with the upper surface of the insulating layer, and a region in contact with the side surface of the first conductive film; a third conductive film having a region in contact with the upper surface of the second conductive film; and an EL layer having a region in contact with the upper surface of the third conductive film, a region in contact with the side surface of the second conductive film, and a region in contact with the side surface of the third conductive film. Display device. [Claim 2] In claim 1, One of the plurality of circuit regions and one of the plurality of display regions are located in overlapping regions in a plan view. Display device. [Claim 3] In claim 1 or claim 2, Wiring is extended between the first layer and the second layer in a direction perpendicular to the substrate. The wiring is electrically connected to the display pixel and the drive circuit. Display device. [Claim 4] In claim 1 or claim 2, The substrate is a glass substrate. Display device.

Images