Display device and electronic apparatus

Abstract

Provided is a display device having a touch sensor and a driver for driving the touch sensor that are built in. This display device has a touch panel function, and an electrode of the touch sensor is electrically connected to a first drive circuit monolithically formed on a substrate on which a pixel circuit is formed. A transistor having a metallic oxide in a semiconductor layer can be used in the first drive circuit. The transistor of the first drive circuit has a structure that can be easily downsized and can be operated at high speed. Consequently, an area occupied by the circuit can be reduced, thereby contributing to the reduction of a bezel width.

Description

Display devices and electronic devices

[0001] One aspect of the present invention relates to a display device.

[0002] Note that one embodiment of the present invention is not limited to the above technical field. Examples of the technical field of one embodiment of the present invention include semiconductor devices, display devices, light-emitting devices, power storage devices, memory devices, lighting devices, input devices (e.g., touch sensors), input / output devices (e.g., antennas, touch panels), and methods for driving, using, or manufacturing these devices.

[0003] Note that in this specification and the like, a semiconductor device refers to any device that can function by utilizing semiconductor characteristics. A transistor and a semiconductor circuit are examples of a semiconductor device. In addition, a memory device, a display device, an imaging device, and an electronic device may include a semiconductor device.

[0004] In recent years, display devices have been used in a variety of applications. Examples of applications of large display devices include home television devices, digital signage, and public information displays (PIDs). Display devices are also widely used in smartphones, tablet terminals, and the like.

[0005] As a display device, a light-emitting device having a light-emitting device (also referred to as a light-emitting element) has been developed. A light-emitting device (also referred to as an EL device or an EL element) utilizing the electroluminescence (hereinafter referred to as EL) phenomenon has characteristics such as being easily thin and lightweight, being capable of responding quickly to an input signal, and being able to be driven using a DC constant voltage power supply. Patent Document 1 discloses an example of a display device using an organic EL element.

[0006] JP 2002-324673 A

[0007] An active matrix display device has a gate driver that selects pixels to which data is written and a source driver that supplies data to the selected pixels. In addition, to provide a display device with touch panel functionality, a touch sensor and a driver to drive the sensor are required.

[0008] These drivers can be implemented using IC chips with the respective functions, which are mounted on the frame of the substrate on which the pixel circuits are formed using techniques such as COG (Chip On Glass), COF (Chip On Film), or TCP (Tape Carrier Package).

[0009] As the number of IC chips mounted on a display increases due to the increase in display area or resolution, the manufacturing cost of the display increases. This also hinders efforts to narrow the frame. To address these issues, it is desirable to form the driver and pixel circuit monolithically on the same substrate.

[0010] Therefore, an object of one embodiment of the present invention is to provide a display device having a touch sensor. Another object is to provide a display device having a built-in touch sensor and a driver for driving the touch sensor. Another object is to provide a display device having a built-in gate driver, a source driver, and a touch sensor driver. Another object is to provide a display device or the like with a novel structure. Another object is to provide a novel semiconductor device or the like.

[0011] Note that the description of these problems does not preclude the existence of other problems. Note that one embodiment of the present invention does not necessarily solve all of these problems. Note that problems other than these will become apparent from the description of the specification, drawings, claims, etc., and it is possible to extract other problems from the description of the specification, drawings, claims, etc.

[0012] One embodiment of the present invention relates to a display device having a touch sensor.

[0013] One embodiment of the present invention includes a pixel circuit, a light-emitting device, a sensor electrode, and a first driver circuit. The first driver circuit has a function of supplying a signal potential to the sensor electrode. The pixel circuit and the first driver circuit are provided over the same substrate. The pixel circuit is provided in a display portion. The pixel circuit includes a first transistor. The first driver circuit includes a second transistor. The light-emitting device includes a first electrode, a light-emitting layer, and a second electrode. The light-emitting layer is provided between the first electrode and the second electrode. The first electrode is a source or a drain of the first transistor. a first insulating layer provided on the second electrode; an opening provided in the first insulating layer in a region outside the connection between the second electrode and the power supply line; a sensor electrode provided on the first insulating layer; the sensor electrode electrically connected to the source or drain of the second transistor through the opening; and the second transistor having a channel formation region along a side surface of the second insulating layer provided on a substrate.

[0014] The sensor electrode can be electrically connected to the source or drain of the second transistor via the connection electrode.

[0015] The connection electrode can be a conductive layer formed using the same process as the first electrode.

[0016] The first transistor may be a transistor having a channel forming region along a side surface of the second insulating layer.

[0017] The second transistor is preferably a transistor having a channel formation region made of metal oxide.

[0018] The pixel circuit may also have a second driver circuit, the pixel circuit having a third transistor, the second driver circuit having a gate driver function, the second driver circuit having a fourth transistor, one of the source and drain of the fourth transistor being electrically connected to the gate of the third transistor, and the fourth transistor being a transistor having a channel formation region along a side surface of the second insulating layer.

[0019] The fourth transistor is preferably a transistor having a channel formation region made of metal oxide.

[0020] The pixel circuit may also have a third driver circuit, the pixel circuit having a fifth transistor, the third driver circuit having a function of a source driver, the third driver circuit having a sixth transistor, one of the source and drain of the sixth transistor being electrically connected to one of the source and drain of the fifth transistor, and the sixth transistor being a transistor having a channel formation region along a side surface of the second insulating layer.

[0021] The sixth transistor is preferably a transistor having a metal oxide in a channel formation region.

[0022] In addition, a camera may be provided on the surface of the substrate opposite to the surface on which the pixel circuit is provided, and in the display unit, a first region that overlaps with the camera lens may have a larger pixel pitch than a second region that does not overlap with the camera lens.

[0023] In the first and second regions, the sensor electrode can be provided by a metal layer so as to have an area overlapping with a wiring electrically connected to the pixel circuit.

[0024] Alternatively, in the first region, the sensor electrode may be formed of a translucent conductive film, and in the second region, the sensor electrode may be formed of a metal layer so as to have an area overlapping with wiring electrically connected to the pixel circuit, and the translucent conductive film may extend to the second region and be electrically connected to the metal layer.

[0025] Alternatively, in the second region, the sensor electrode may be provided as a metal layer so as to have an area overlapping with wiring electrically connected to the pixel circuit, and in the first region, no sensor electrode may be provided.

[0026] According to one embodiment of the present invention, a display device having a touch sensor can be provided. Alternatively, a display device having a built-in touch sensor and a driver for driving the touch sensor can be provided. Alternatively, a display device having a built-in gate driver, a source driver, and a touch sensor driver can be provided. Alternatively, a display device or the like with a novel structure can be provided. Alternatively, a novel semiconductor device or the like can be provided.

[0027] The description of multiple effects does not preclude the existence of other effects. Furthermore, one embodiment of the present invention does not necessarily have all of the exemplified effects. Furthermore, problems, effects, and novel features of one embodiment of the present invention other than those described above will become apparent from the description and drawings of this specification.

[0028] FIG. 1 is a diagram illustrating a display device. FIG. 2 is a block diagram illustrating a display device. FIGS. 3A to 3C are diagrams illustrating a touch sensor. FIGS. 4A to 4F are diagrams illustrating a pixel layout. FIGS. 5A to 5C are diagrams illustrating a pixel circuit. FIGS. 6A to 6E are diagrams illustrating a configuration example of a display device. FIGS. 7A to 7D are diagrams illustrating a configuration example of a display device. FIGS. 8A and 8B are diagrams illustrating a vertical transistor. FIGS. 9A and 9B are diagrams illustrating a vertical transistor. FIG. 10A is a diagram illustrating a configuration example of a display device. FIGS. 10B and 10C are diagrams illustrating a transistor. FIG. 11 is a diagram illustrating a configuration example of a display device. FIGS. 12A to 12C are diagrams illustrating a configuration example of a display device. FIGS. 13A and 13B are diagrams illustrating sensor electrodes. FIGS. 14A and 14B are diagrams illustrating sensor electrodes. FIGS. 15A and 15B are diagrams illustrating sensor electrodes. FIGS. 16A and 16B are diagrams illustrating sensor electrodes. Fig. 17A and Fig. 17B are diagrams illustrating the connection configuration of sensor electrodes and drive circuits. Fig. 18A to Fig. 18C are diagrams illustrating sensor electrodes. Fig. 19A to Fig. 19F are diagrams illustrating an example configuration of an electronic device. Fig. 20A to Fig. 20C are diagrams illustrating an example configuration of an electronic device. Fig. 21A to Fig. 21C are diagrams illustrating an example configuration of an electronic device.

[0029] Hereinafter, embodiments will be described with reference to the drawings. However, it will be readily understood by those skilled in the art that the embodiments can be implemented in many different ways and that various changes in form and details can be made without departing from the spirit and scope of the present invention. Therefore, the present invention should not be interpreted as being limited to the description of the following embodiments.

[0030] Furthermore, when it is stated in this specification that X and Y are connected, it is understood that the following cases are disclosed in this specification: when X and Y are electrically connected, when X and Y are functionally connected, and when X and Y are directly connected. Therefore, it is not limited to a specific connection relationship, for example, a connection relationship shown in a figure or text, and it is understood that connections other than those shown in a figure or text are also disclosed in a figure or text. X and Y are understood to be objects (e.g., devices, elements, circuits, wiring, electrodes, terminals, conductive films, layers, etc.).

[0031] As an example of a case where X and Y are electrically connected, one or more elements (e.g., a switch, a transistor, a capacitance element, an inductor, a resistance element, a diode, a display device, a light-emitting device, a load, etc.) that enable the electrical connection between X and Y can be connected between X and Y. The on and off states of the switch are controlled. In other words, the switch has the function of being in a conductive state (on state) or a non-conductive state (off state) and controlling whether or not a current flows.

[0032] As an example of a case where X and Y are functionally connected, one or more circuits that enable the functional connection between X and Y (for example, logic circuits (inverters, NAND circuits, NOR circuits, etc.), signal conversion circuits (digital-analog conversion circuits, analog-digital conversion circuits, gamma correction circuits, etc.), potential level conversion circuits (power supply circuits (boosting circuits, step-down circuits, etc.), level shifter circuits that change the potential level of a signal, etc.), voltage sources, current sources, switching circuits, amplifier circuits (circuits that can increase the signal amplitude or amount of current, operational amplifiers, differential amplifier circuits, source follower circuits, buffer circuits, etc.), signal generation circuits, memory circuits, control circuits, etc.) can be connected between X and Y. As an example, even if another circuit is sandwiched between X and Y, if a signal output from X is transmitted to Y, X and Y are considered to be functionally connected.

[0033] It should be noted that when it is explicitly stated that X and Y are electrically connected, this includes the case where X and Y are electrically connected (i.e., the case where X and Y are connected with another element or another circuit sandwiched between them) and the case where X and Y are directly connected (i.e., the case where X and Y are connected without another element or another circuit sandwiched between them).

[0034] Furthermore, for example, it can be expressed as follows: "X, Y, and the source (or first terminal, etc.) and drain (or second terminal, etc.) of the transistor are electrically connected to each other, and are electrically connected in the order of X, the source (or first terminal, etc.) of the transistor, the drain (or second terminal, etc.) of the transistor, and Y." Or, it can be expressed as follows: "The source (or first terminal, etc.) of the transistor is electrically connected to X, and the drain (or second terminal, etc.) of the transistor is electrically connected to Y, and X, the source (or first terminal, etc.) of the transistor, the drain (or second terminal, etc.) of the transistor, and Y are electrically connected in this order." Or, it can be expressed as follows: "X is electrically connected to Y via the source (or first terminal, etc.) and drain (or second terminal, etc.) of the transistor, and X, the source (or first terminal, etc.) of the transistor, the drain (or second terminal, etc.) of the transistor, and Y are provided in this connection order." By using expressions similar to these examples to define the order of connections in a circuit configuration, the source (or first terminal, etc.) and drain (or second terminal, etc.) of a transistor can be distinguished and the technical scope can be determined. Note that these expressions are merely examples and are not limiting. Here, X and Y represent objects (e.g., devices, elements, circuits, wiring, electrodes, terminals, conductive films, layers, etc.).

[0035] Note that even when independent components are shown electrically connected in a circuit diagram, one component may have the functions of multiple components. For example, if part of a wiring also functions as an electrode, one conductive film has the functions of both a wiring and an electrode. Therefore, in this specification, the term "electrically connected" also includes such cases where one conductive film has the functions of multiple components.

[0036] Furthermore, in this specification, the term "capacitive element" can refer to, for example, a circuit element having a capacitance value higher than 0 F, a region of wiring having a capacitance value higher than 0 F, parasitic capacitance, or the gate capacitance of a transistor. Therefore, in this specification, the term "capacitive element" includes not only a circuit element including a pair of electrodes and a dielectric between the electrodes, but also a parasitic capacitance occurring between wiring and one of the source or drain of a transistor and the gate, and the like. Furthermore, terms such as "capacitive element," "parasitic capacitance," and "gate capacitance" can be replaced with terms such as "capacitance," and conversely, the term "capacitance" can be replaced with terms such as "capacitive element," "parasitic capacitance," and "gate capacitance." Furthermore, the term "pair of electrodes" in "capacitance" can be replaced with "pair of conductors," "pair of conductive regions," "pair of regions," and the like. The capacitance value can be, for example, 0.05 fF or more and 10 pF or less. It may also be, for example, 1 pF or more and 10 μF or less.

[0037] Furthermore, in this specification, a transistor has three terminals called a gate, a source, and a drain. The gate is a control terminal that controls the conduction state of the transistor. The two terminals that function as a source or a drain are input / output terminals of the transistor. One of the two input / output terminals becomes a source and the other becomes a drain depending on the transistor's conductivity type (n-channel or p-channel) and the level of the potential applied to the three terminals of the transistor. Therefore, in this specification, the terms source and drain are interchangeable. Furthermore, in this specification, when describing the connection relationship of a transistor, the terms "one of the source or drain" (or first electrode or first terminal) and "the other of the source or drain" (or second electrode or second terminal) are used. Note that, depending on the transistor structure, a backgate may be included in addition to the three terminals described above. In this case, in this specification, one of the gate or backgate of the transistor may be referred to as the first gate, and the other of the gate or backgate of the transistor may be referred to as the second gate. Furthermore, for the same transistor, the terms "gate" and "backgate" may be interchangeable. Furthermore, when a transistor has three or more gates, the gates may be referred to as a first gate, a second gate, a third gate, and so on in this specification and the like.

[0038] Furthermore, in this specification and the like, the term "node" can be rephrased as a terminal, wiring, electrode, conductive layer, conductor, impurity region, etc., depending on the circuit configuration, device structure, etc. Furthermore, the term "node" can be rephrased as a terminal, wiring, etc.

[0039] Furthermore, in this specification, the ordinal numbers "first," "second," and "third" are used to avoid confusion between components. Therefore, they do not limit the number of components. Furthermore, they do not limit the order of the components. For example, a component referred to as "first" in one embodiment of this specification may be a component referred to as "second" in another embodiment, in the claims, etc. Furthermore, for example, a component referred to as "first" in one embodiment of this specification, etc. may be omitted in another embodiment, in the claims, etc.

[0040] Furthermore, in this specification, terms indicating position, such as "above," "below," "upward," or "belowward," may be used for convenience in describing the positional relationship between components with reference to the drawings. Furthermore, the positional relationship between components changes as appropriate depending on the direction in which each configuration is depicted. Therefore, the terms are not limited to those described in the specification, and can be rephrased appropriately depending on the situation. For example, the expression "insulator located on the upper surface of a conductor" can be rephrased as "insulator located on the lower surface of a conductor" by rotating the orientation of the drawing 180 degrees.

[0041] Furthermore, the terms "above" and "below" do not limit the positional relationship of components to being directly above or below and in direct contact with each other. For example, the expression "electrode B on insulating layer A" does not require that electrode B be formed on insulating layer A in direct contact with it, and does not exclude the inclusion of other components between insulating layer A and electrode B.

[0042] Furthermore, in this specification and the like, the term "overlap" does not limit the state of the stacking order of components, etc. For example, the expression "electrode B overlapping insulating layer A" does not limit the state in which electrode B is formed on insulating layer A, but does not exclude the state in which electrode B is formed under insulating layer A or the state in which electrode B is formed on the right (or left) side of insulating layer A, etc.

[0043] Furthermore, in this specification and the like, the terms "adjacent" and "close to" do not necessarily mean that components are in direct contact with each other. For example, the expression "electrode B adjacent to insulating layer A" does not require that insulating layer A and electrode B are formed in direct contact with each other, and does not exclude the inclusion of other components between insulating layer A and electrode B.

[0044] Furthermore, in this specification and the like, terms such as "film" and "layer" can be interchanged depending on the situation. For example, the term "conductive layer" may be changed to the term "conductive film." Or, for example, the term "insulating film" may be changed to the term "insulating layer." Or, depending on the situation, terms such as "film" and "layer" may be replaced with other terms without using terms such as "film" and "layer." For example, the term "conductive layer" or "conductive film" may be changed to the term "conductor." Or, the term "conductor" may be changed to the term "conductive layer" or "conductive film." Or, for example, the term "insulating layer" or "insulating film" may be changed to the term "insulator." Or, the term "insulator" may be changed to the term "insulating layer" or "insulating film."

[0045] Furthermore, in this specification and the like, terms such as "electrode," "wiring," and "terminal" do not functionally limit these components. For example, an "electrode" may be used as part of a "wiring," and vice versa. Furthermore, the terms "electrode" and "wiring" include cases where multiple "electrodes" or "wirings" are integrally formed. Furthermore, for example, a "terminal" may be used as part of a "wiring" or "electrode," and vice versa. Furthermore, the term "terminal" includes cases where multiple "electrodes," "wirings," "terminals," etc. are integrally formed. Therefore, for example, an "electrode" can be part of a "wiring" or "terminal," and a "terminal" can be part of a "wiring" or "electrode." Furthermore, terms such as "electrode," "wiring," and "terminal" may be replaced with terms such as "region" in some cases.

[0046] Furthermore, in this specification and the like, terms such as "wiring," "signal line," and "power line" may be interchangeable depending on the circumstances. For example, the term "wiring" may be changed to the term "signal line." For example, the term "wiring" may be changed to the term "power line." Vice versa, terms such as "signal line" and "power line" may be changed to the term "wiring." A term such as "power line" may be changed to the term "signal line." Vice versa, terms such as "signal line" may be changed to the term "power line." Furthermore, the term "potential" applied to a wiring may be changed to the term "signal" depending on the circumstances. Vice versa, terms such as "signal" may be changed to the term "potential."

[0047] In this specification, "parallel" refers to a state in which two straight lines are arranged at an angle of -10° or more and 10° or less. Therefore, it also includes cases where the angle is -5° or more and 5° or less. Furthermore, "substantially parallel" or "roughly parallel" refers to a state in which two straight lines are arranged at an angle of -30° or more and 30° or less. Furthermore, "perpendicular" refers to a state in which two straight lines are arranged at an angle of 80° or more and 100° or less. Therefore, it also includes cases where the angle is 85° or more and 95° or less. Furthermore, "substantially perpendicular" or "approximately perpendicular" refers to a state in which two straight lines are arranged at an angle of 60° or more and 120° or less.

[0048] In this specification and elsewhere, when referring to counting values ​​and measurement values, terms such as "identical," "same," "equal," or "uniform" (including synonyms thereof) are used, unless otherwise specified, and include an error of plus or minus 20%.

[0049] The embodiments described in this specification will be described with reference to the drawings. However, the embodiments can be implemented in many different ways, and those skilled in the art will readily understand that various changes in form and detail can be made without departing from the spirit and scope of the present invention. Therefore, the present invention should not be construed as being limited to the description of the embodiments. Note that in the configuration of the invention of the embodiments, the same reference numerals are used in different drawings for the same parts or parts having similar functions, and repeated description thereof may be omitted. Furthermore, when referring to similar functions, the same hatch pattern may be used and no particular reference numeral may be assigned. Furthermore, to make the drawings easier to understand, the illustration of some components may be omitted in perspective views, top views, etc.

[0050] In addition, in the drawings and the like relating to this specification, the size, layer thickness, or region may be exaggerated for clarity. Therefore, the size or aspect ratio is not necessarily limited. Note that the drawings are schematic illustrations of ideal examples and are not limited to the shapes or values ​​shown in the drawings. For example, variations in signal, voltage, or current due to noise, or variations in signal, voltage, or current due to timing deviations, etc. may be included.

[0051] In addition, in drawings and the like relating to this specification, arrows indicating the X direction, Y direction, and Z direction may be used. In this specification and the like, the "X direction" refers to the direction along the X axis, and the forward direction and the reverse direction may not be distinguished unless explicitly stated. The same applies to the "Y direction" and the "Z direction." The X direction, Y direction, and Z direction are directions that intersect with each other. More specifically, the X direction, Y direction, and Z direction are directions that are perpendicular to each other. In this specification and the like, one of the X direction, Y direction, and Z direction may be referred to as the "first direction" or "first direction." The other may be referred to as the "second direction" or "second direction." The remaining one may be referred to as the "third direction" or "third direction."

[0052] In this specification, when the same symbol is used for multiple elements, and particularly when it is necessary to distinguish between them, an identifying symbol such as “A”, “b”, “_1”, "[n]”, or "[m, n]” may be added to the symbol.

[0053] In this specification, a display device having a connector such as an FPC (Flexible Printed Circuit) or a TCP (Tape Carrier Package) attached to a substrate constituting the display device, or a display device having an IC (Integrated Circuit) directly mounted on a substrate constituting the display device by a COG (Chip On Glass) method, may be referred to as a display device, a display module, or the like.

[0054] Embodiment 1 In this embodiment, a display device according to one embodiment of the present invention will be described. One embodiment of the present invention is a display device having a touch panel function. An electrode of a touch sensor is provided so as to overlap with a display portion, and the electrode is electrically connected to a first driver circuit monolithically formed on a substrate on which a pixel circuit is formed.

[0055] An in-cell touch panel in which a touch sensor is built into a display device can reduce the number of components, thereby reducing costs.

[0056] The pixel circuit and the first driver circuit can use transistors having metal oxide in their semiconductor layers. The transistors in the first driver circuit have a structure that can be easily miniaturized and can operate at high speed. Therefore, the area occupied by the circuit can be reduced, contributing to a narrower frame.

[0057] In addition, a second driver circuit (gate driver) that drives the pixel circuit and a third driver circuit (source driver) can also be formed using transistors having metal oxide in their semiconductor layers, and the three driver circuits can be formed in a monolithic manner on the substrate on which the pixel circuit is formed.

[0058] By using one embodiment of the present invention having such characteristics, the cost required for mounting an IC chip can be reduced and the frame of a display device can be narrowed.

[0059] 1 is a schematic diagram illustrating a display device according to one embodiment of the present invention. The display device according to one embodiment of the present invention includes a pixel and a conductive layer that forms an electrode of a touch sensor (hereinafter, referred to as a sensor electrode) between a pair of substrates. The display device according to one embodiment of the present invention includes a plurality of sensor electrodes that overlap a display portion. Note that FIG. 1 illustrates a cutout of a part of the sensor electrode.

[0060] The display device 100 has a configuration in which a sensor electrode 130 is provided between a substrate 110 and a substrate 140. A display unit 111 is provided on the substrate 110, and the sensor electrode 130 is provided on the display unit 111. As shown in the enlarged view, the pixel 120 that constitutes the display unit 111 has a plurality of sub-pixels 122. By using a plurality of sub-pixels 122 that emit light of different colors, full-color display is possible.

[0061] A drive circuit 114 (sensor driver) for driving the touch sensor is also provided on the substrate 110. The drive circuit 114 is electrically connected to the sensor electrode 130 and the FPC 119. The sensor electrode 130 is also electrically connected to the FPC 119.

[0062] In addition, a driver circuit 112 and a driver circuit 113 for driving pixel circuits included in the pixels 120 are provided over the substrate 110. The driver circuit 112 and the driver circuit 113 are electrically connected to an FPC 118.

[0063] The FPC 118 and the FPC 119 may be integrated into one. Although the example shows the drive circuits 112, 113, and 114 being provided as a monolithic type, one or more of them may be replaced with a form in which an IC chip is mounted. Furthermore, depending on the type of touch sensor to be provided, the drive circuit 114 may not be necessary.

[0064] 2 is a block diagram illustrating the display device 100. The display device 100 has a pixel array 121 provided in a display unit 111, a drive circuit 112, a drive circuit 113, and a drive circuit 114. The pixel array 121 has pixels 120 arranged in the column direction and the row direction.

[0065] The pixel 120 includes a sub-pixel 122. The sub-pixel 122 has a function of emitting light for display.

[0066] In this specification, the smallest unit within a single "pixel" that performs independent operation is defined as a "sub-pixel" for convenience in the explanation, but "pixel" may be replaced with "region" and "sub-pixel" may be replaced with "pixel".

[0067] The subpixel 122 has a light-emitting device that emits visible light. As the light-emitting device, it is preferable to use an EL element such as an OLED (organic light-emitting diode) or a QLED (quantum-dot light-emitting diode). Examples of light-emitting materials that the EL element may have include fluorescent materials, phosphorescent materials, thermally activated delayed fluorescence (TADF) materials), and inorganic compounds (such as quantum dot materials). Alternatively, an LED such as a micro LED (light-emitting diode) may be used as the light-emitting device.

[0068] The drive circuits 112 and 113 are drivers for driving the pixels 120. The drive circuit 114 is a driver for driving the touch sensor. The drive circuits 112, 113, and 114 can be, for example, a shift register circuit that operates at high speed.

[0069] The driver circuit 112 can function as a gate driver, and the driver circuit 113 can function as a source driver. The driver circuit 112 is electrically connected to the sub-pixels 122 via gate lines GL. The driver circuit 113 is electrically connected to the sub-pixels 122 via source lines SL. An FPC 118 is electrically connected to the driver circuits 112 and 113, and a signal potential can be input from the outside via the FPC 118. A demultiplexer may be provided between the driver circuit 112 and the sub-pixels 122.

[0070] Sensor electrodes 130X and 130Y, which function as electrodes of the touch sensor, are provided on the pixel array 121. The sensor electrode 130X has a configuration in which multiple conductive layers, each shown as a square, are connected in the X direction. The sensor electrode 130Y has a configuration in which multiple conductive layers, each shown as a square, are connected in the Y direction.

[0071] In the figures described in this embodiment, the sizes of the sensor electrodes 130X and 130Y are merely examples and are not limited to the sizes shown in the drawings. The sizes of the sensor electrodes 130X and 130Y may be set according to the product specifications. For example, one of the conductive layers shown as a square may be arranged to have an area overlapping with 1 to 100,000 pixels.

[0072] For example, the sensor electrode 130X can be electrically connected to the drive circuit 114. The drive circuit 114 is connected to an FPC 119, and a signal potential can be input to the sensor electrode 130X from the outside via the FPC 119. In addition, the sensor electrode 130Y can be connected to the FPC 119, and the current flowing through the sensor electrode 130Y can be read out via the FPC 119.

[0073] 3A is a top view illustrating a portion of the touch sensor, which includes conductive layers 131X (131X1-131X3) that function as sensor electrodes 130X provided in the X direction and conductive layers 131Y (131Y1-131Y3) that function as sensor electrodes 130Y provided in the Y direction.

[0074] 3A illustrates a configuration in which the conductive layers 131X and 131Y are regularly arranged as rectangular conductive layers, but the configuration is not limited thereto. For example, the outer shape of the conductive layers may be circular, triangular, pentagonal, hexagonal, octagonal, etc.

[0075] The conductive layer 131X and the conductive layer 131Y can function as electrodes of a capacitance-type touch sensor. Capacitive touch sensors include surface capacitance touch sensors and projected capacitance touch sensors. Projected capacitance touch sensors include self-capacitance touch sensors and mutual capacitance touch sensors, primarily depending on the driving method. The mutual capacitance touch sensor is preferred because it enables simultaneous multi-point detection.

[0076] In the projected self-capacitance method, a pulse voltage is applied to each of the conductive layers 131X and 131Y in a scanning manner, and the value of the current flowing through each layer at that time is detected. When a detected object approaches, the magnitude of the current changes, and by detecting this difference, position information of the detected object can be obtained. In the projected mutual capacitance method, a pulse voltage is applied to either the conductive layer 131X or the conductive layer 131Y in a scanning manner, and the current flowing through the other layer is detected, thereby obtaining position information of the detected object.

[0077] In this embodiment, an example is shown in which a projected mutual capacitance method is used, a driving circuit 114 is connected to the conductive layer 131X, and a current flowing through the conductive layer 131Y is detected. Note that when a projected self-capacitance method is used, the driving circuit 114 can be eliminated.

[0078] An insulating layer is sandwiched between the conductive layers 131X and 131Y at their intersections to prevent short circuits. The insulating layer may be provided only at the intersections, or may be provided to cover the conductive layer 131X. Furthermore, as shown in FIG. 3B , a conductive layer 132 may be provided at the intersections to electrically connect adjacent rectangular conductive layers.

[0079] The conductive layer 131X and the conductive layer 131Y are preferably formed using a light-transmitting conductive material. Examples of the light-transmitting conductive material include conductive oxides such as indium oxide, indium tin oxide, indium zinc oxide, zinc oxide, and zinc oxide doped with gallium. A film containing graphene can also be used. The film containing graphene can be formed, for example, by reducing a film containing graphene oxide. Examples of a reduction method include a method using heat.

[0080] Alternatively, a metal or alloy thin enough to have light-transmitting properties can be used. For example, a metal such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, or titanium, or an alloy containing such a metal, can be used. Alternatively, a nitride of such a metal or alloy (e.g., titanium nitride) can be used. Furthermore, a stacked film formed by stacking two or more conductive films containing the above-mentioned materials can be used.

[0081] Furthermore, the conductive layers 131X and 131Y may be formed using a conductive film that is thin enough to be invisible to the user. For example, by forming such a conductive film into a lattice (mesh) pattern, high conductivity and high visibility of the display device can be achieved. In this case, it is preferable that the conductive film has a portion with a width of 30 nm to 100 μm, preferably 50 nm to 50 μm, and more preferably 50 nm to 20 μm. In particular, a conductive film with a pattern width of 10 μm or less is preferable because it is extremely difficult for the user to see.

[0082] 3C shows an example in which a lattice-shaped conductive film is used for the conductive layer 131X. When a lattice-shaped conductive film is used, the transmittance of light emitted by the light-emitting device can be increased by arranging the conductive film so as not to overlap with the light-emitting device.

[0083] Conductive nanowires may also be used for the conductive layers 131X and 131Y. By dispersing the nanowires at an appropriate density so that adjacent nanowires are in contact with each other, a two-dimensional network is formed, allowing the nanowires to function as a highly light-transmitting conductive film. For example, nanowires with an average diameter of 1 nm to 100 nm, preferably 5 nm to 50 nm, and more preferably 5 nm to 25 nm, can be used. Metal nanowires such as Ag nanowires, Cu nanowires, and Al nanowires, or carbon nanotubes can be used as the nanowires. For example, Ag nanowires can achieve a light transmittance of 89% or more and a sheet resistance of 40 Ω / □ to 100 Ω / □.

[0084] 4A to 4F are diagrams illustrating pixel layouts. The arrangement of sub-pixels is not particularly limited, and various methods can be applied. Examples of the arrangement of sub-pixels include a stripe arrangement, an S-stripe arrangement, a matrix arrangement, a delta arrangement, a Bayer arrangement, and a pentile arrangement.

[0085] Examples of the top surface shape of the subpixel include a triangle, a quadrangle (including a rectangle and a square), a polygon such as a pentagon, a polygon with rounded corners, an ellipse, a circle, etc. Here, the top surface shape of the subpixel corresponds to the top surface shape of the light-emitting region of the light-emitting device.

[0086] An S-stripe arrangement is applied to the pixel 120 shown in Fig. 4A. The pixel 120 shown in Fig. 4A is composed of three subpixels 122, namely, subpixels 122a, 122b, and 122c. For example, the subpixel 122a can be a blue subpixel, the subpixel 122b can be a red subpixel, and the subpixel 122c can be a green subpixel.

[0087] The pixel 120 shown in FIG. 4B includes subpixel 122a having a generally trapezoidal or triangular top surface shape with rounded corners, subpixel 122b having a generally trapezoidal or triangular top surface shape with rounded corners, and subpixel 122c having a generally rectangular or hexagonal top surface shape with rounded corners. Furthermore, subpixel 122a has a larger light-emitting area than subpixel 122b. In this manner, the shape and size of each subpixel can be determined independently. For example, the more reliable the light-emitting device, the smaller the size can be. For example, subpixel 122a can be a green subpixel, subpixel 122b can be a red subpixel, and subpixel 122c can be a blue subpixel.

[0088] The pixels 120a and 120b shown in Fig. 4C are arranged in a Pentile arrangement. Fig. 4C shows an example in which pixel 120a having subpixels 122a and 122b and pixel 120b having subpixels 122b and 122c are arranged alternately. For example, subpixel 122a can be a red subpixel, subpixel 122b can be a green subpixel, and subpixel 122c can be a blue subpixel.

[0089] The pixels 120a and 120b shown in Figures 4D and 4E are arranged in a delta configuration, with each subpixel having a generally rectangular shape with rounded corners in the top view, and each subpixel having a circular shape in the top view, in Figure 4D and 4E, respectively.

[0090] Pixel 120a has two subpixels (subpixels 122a and 122b) in the top row (first row) and one subpixel (subpixel 122c) in the bottom row (second row). Pixel 120b has one subpixel (subpixel 122c) in the top row (first row) and two subpixels (subpixels 122a and 122b) in the bottom row (second row). For example, subpixel 122a can be a red subpixel, subpixel 122b can be a green subpixel, and subpixel 122c can be a blue subpixel.

[0091] 4F shows an example in which subpixels of each color are arranged in a zigzag pattern. Specifically, when viewed from above, the positions of the upper edges of two subpixels aligned in the column direction (e.g., subpixels 122a and 122b, or subpixels 122b and 122c) are misaligned. For example, subpixel 122a can be a red subpixel, subpixel 122b can be a green subpixel, and subpixel 122c can be a blue subpixel.

[0092] In photolithography, the finer the pattern to be processed, the more significant the effect of light diffraction becomes. This reduces the fidelity of the photomask pattern when it is transferred by exposure, making it difficult to process the resist mask into the desired shape. Therefore, even if the photomask pattern is rectangular, it is likely to have rounded corners. As a result, the top surface shape of the subpixel may become a polygon with rounded corners, an ellipse, a circle, or the like.

[0093] 5A shows an example of a pixel circuit that can be applied to the sub-pixel 122. The pixel circuit includes a transistor M1, a transistor M2, a transistor M3, a capacitor C1, and a light-emitting device EL. The pixel circuit is also electrically connected to a gate line GL and a source line SL (see FIG. 2).

[0094] The gate of the transistor M1 is electrically connected to the gate line GL, and one of the source or drain is electrically connected to the source line SL, and the other is electrically connected to one electrode of the capacitor C1 and the gate of the transistor M2. The transistor M2 has one of the source or drain electrically connected to a wiring AL, and the other of the source or drain electrically connected to one electrode of the light-emitting device EL, the other electrode of the capacitor C1, and one of the source or drain of the transistor M3. The transistor M3 has the gate electrically connected to the gate line GL, and the other of the source or drain electrically connected to a wiring RL. The other electrode of the light-emitting device EL is electrically connected to a wiring CL.

[0095] The source line SL is supplied with a data potential D. The gate line GL is supplied with a selection signal. The selection signal includes a potential that turns on a transistor and a potential that turns off a transistor.

[0096] A reset potential is applied to the wiring RL. An anode potential is applied to the wiring AL. A cathode potential is applied to the wiring CL. In the subpixel 122, the anode potential is higher than the cathode potential. The reset potential applied to the wiring RL can be a potential such that the potential difference between the reset potential and the cathode potential is smaller than the threshold voltage of the light-emitting device EL. The reset potential can be a potential higher than the cathode potential, the same as the cathode potential, or a potential lower than the cathode potential.

[0097] The transistors M1 and M3 function as switches. The transistor M2 functions as a transistor for controlling the current flowing through the light-emitting device EL. For example, it can be said that the transistor M1 functions as a selection transistor and the transistor M2 functions as a drive transistor.

[0098] Here, the transistors M1 to M3 may be transistors having metal oxide in their channel formation regions (hereinafter referred to as OS transistors). Alternatively, all of the transistors M1 to M3 may be transistors having silicon (single crystal silicon, polycrystalline silicon, microcrystalline silicon, or amorphous silicon) in their channel formation regions (hereinafter referred to as Si transistors). Alternatively, the transistors M1 and M3 may be OS transistors, and the transistor M2 may be a Si transistor.

[0099] Alternatively, one or more of the transistors included in the driver circuits 112, 113, and 114 may be Si transistors and the remaining transistors may be OS transistors. Alternatively, one or more of the driver circuits 112, 113, and 114 may be Si transistors and the remaining transistors may be OS transistors.

[0100] As the OS transistor, a transistor using an oxide semiconductor for a semiconductor layer in which a channel is formed can be used. The semiconductor layer preferably contains, for example, indium, M (M is one or more selected from gallium, aluminum, silicon, boron, yttrium, tin, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, and magnesium), and zinc. In particular, M is preferably one or more selected from aluminum, gallium, yttrium, and tin. In particular, an oxide containing indium, gallium, and zinc (also referred to as IGZO) is preferably used for the semiconductor layer of the OS transistor. Alternatively, an oxide containing indium, tin, and zinc is preferably used. Alternatively, an oxide containing indium, gallium, tin, and zinc is preferably used.

[0101] A transistor using an oxide semiconductor, which has a wider band gap and a lower carrier concentration than silicon, can achieve an extremely small off-state current. Therefore, due to the small off-state current, charge stored in a capacitor connected in series with the transistor can be held for a long period of time. Therefore, it is preferable to use transistors including oxide semiconductors for the transistors M1 and M3 connected in series with the capacitor C1. By using transistors including oxide semiconductors as the transistors M1 and M3, charge held in the capacitor C1 can be prevented from leaking through the transistor M1 or the transistor M3. Furthermore, because charge held in the capacitor C1 can be held for a long period of time, a still image can be displayed for a long period of time without rewriting pixel data.

[0102] Although the transistors are shown as n-channel transistors in FIG. 5A, p-channel transistors can also be used.

[0103] Further, as a transistor included in a pixel circuit, a transistor having a pair of gates overlapping with each other with a semiconductor layer interposed therebetween can be used.

[0104] In a transistor having a pair of gates, when the pair of gates are electrically connected to each other and supplied with the same potential, the on-state current of the transistor is increased and the saturation characteristics are improved. A potential for controlling the threshold voltage of the transistor may be supplied to one of the pair of gates. Supplying a constant potential to one of the pair of gates can improve the stability of the electrical characteristics of the transistor. For example, one gate of the transistor may be electrically connected to a wiring to which a constant potential is supplied, or to its own source or drain.

[0105] 5B is an example in which transistors M1 and M3 each have a pair of gates. The pair of gates of the transistor M1 and the transistor M3 are electrically connected. This configuration can shorten the period for writing data to the pixel circuit.

[0106] 5C is an example in which a transistor having a pair of gates is used for transistor M2 in addition to transistors M1 and M3. The pair of gates of transistor M2 are electrically connected. By using such a transistor for transistor M2, the saturation characteristics are improved, making it easier to control the emission brightness of light-emitting device EL, and display quality can be improved.

[0107] Next, the configuration of the light-emitting device and the connection between the sensor electrodes and the drive circuit 114 will be described.

[0108] One embodiment of the present invention is a display device including a light-emitting device. For example, a full-color display device can be realized by including three types of light-emitting devices that emit red (R), green (G), or blue (B) light in a pixel. In the following description, an element such as a light-emitting layer sandwiched between a pair of electrodes of a light-emitting device is referred to as an EL layer.

[0109] In this specification and the like, a device fabricated using a metal mask or an FMM (fine metal mask, high-resolution metal mask) may be referred to as a device with an MM (metal mask) structure. In addition, in this specification and the like, a device fabricated without using a metal mask or an FMM may be referred to as a device with an MML (metal maskless) structure. Because a display device having a device with an MML structure is fabricated without using a metal mask, it has a higher degree of design freedom in terms of pixel arrangement, pixel shape, and the like than a display device having a device with an FMM structure or an MM structure.

[0110] In the method for manufacturing a display device with an MML structure, the island-shaped organic layer (hereinafter referred to as the EL layer) constituting the organic EL element is not formed using a metal mask pattern, but is formed by forming the EL layer on the entire surface and then processing it. This makes it possible to realize high-definition display devices or display devices with high aperture ratios, which have been difficult to achieve until now. Furthermore, since the EL layer can be made separately for each color, it is possible to realize display devices with extremely vivid images, high contrast, and high display quality. Furthermore, by providing a sacrificial layer on the EL layer, damage to the EL layer during the display device manufacturing process can be reduced, thereby improving the reliability of the light-emitting device.

[0111] While it is difficult to achieve a gap of less than 10 μm between two adjacent EL layers using a metal mask, the above method can narrow the gap to 3 μm or less, 2 μm or less, or even 1 μm or less. For example, by using an exposure device for LSIs, the gap can be narrowed to 500 nm or less, 200 nm or less, 100 nm or less, or even 50 nm or less. This significantly reduces the area of ​​the non-light-emitting region that may exist between the two light-emitting devices, enabling the aperture ratio to approach 100%. For example, the aperture ratio can be 50% or more, 60% or more, 70% or more, 80% or more, or even 90% or more, and even less than 100%.

[0112] Furthermore, the size of the EL layer itself can be made much smaller than when a metal mask is used. Furthermore, for example, when a metal mask is used to separately fabricate EL layers, thickness variations occur between the center and edges of the island-shaped EL layer, resulting in a smaller effective area that can be used as a light-emitting region relative to the overall area of ​​the EL layer. On the other hand, with the above-described fabrication method, the island-shaped EL layer is formed by processing (deleting) a film formed to a uniform thickness, making the thickness uniform. Even if the size of the EL layer is minute (deleted), almost the entire area can be used as a light-emitting region. Therefore, the above-described fabrication method can achieve both high definition and a high aperture ratio.

[0113] Organic films formed using FMM (Fine Metal Mask) often have an extremely small taper angle (e.g., greater than 0 degrees and less than 30 degrees), with the thickness decreasing toward the edge. Therefore, organic films formed using FMM have a continuous connection between their side and top surfaces, making it difficult to clearly identify the side surfaces. On the other hand, one embodiment of the present invention has an EL layer processed without using FMM, resulting in clear side surfaces. In particular, one embodiment of the present invention preferably has a portion where the taper angle of the EL layer is 30 degrees or more and less than 90 degrees, preferably 60 degrees or more and less than 90 degrees.

[0114] In this specification, the term "tapered end of an object" refers to a cross-sectional shape in which the angle between the side surface (surface) and the surface to be formed (bottom surface) in the end region is greater than 0 degrees and less than 90 degrees, and the thickness increases continuously from the end. The taper angle refers to the angle between the bottom surface (surface to be formed) and the side surface (surface) at the end of the object.

[0115] A more specific example will be described below.

[0116] 6A shows a schematic top view of the display device 100. The display device 100 has a plurality of red light-emitting devices 90R, a plurality of green light-emitting devices 90G, and a plurality of blue light-emitting devices 90B. Furthermore, a sensor electrode 130X or a sensor electrode 130Y, which is an electrode of a touch sensor, is provided on each of these light-emitting devices.

[0117] The light emitting devices 90R, 90G, and 90B are arranged in a matrix. The arrangement of the light emitting devices is not limited to this, and other arrangements such as a stripe arrangement, an S-stripe arrangement, a delta arrangement, a Bayer arrangement, and a zigzag arrangement may also be used, as well as a pentile arrangement and a diamond arrangement.

[0118] 6A also shows a connection electrode 311a electrically connected to the common electrode 313. The connection electrode 311a is given a potential (e.g., an anode potential or a cathode potential) to be supplied to the common electrode 313. In other words, the connection electrode 311a can also be considered a part of a power supply line. The connection electrode 311a is provided outside the display section in which the light-emitting devices 90R and the like are arranged, and is electrically connected to the common electrode 313 at a connection section 330a.

[0119] The connection electrode 311a can be provided along the periphery of the display unit. For example, it may be provided along one side of the periphery of the display unit, or it may be provided over two or more sides of the periphery of the display area. That is, when the top surface shape of the display area is rectangular, the top surface shape of the connection electrode 311a can be strip-shaped, L-shaped, U-shaped (square bracket-shaped), square-shaped, or the like.

[0120] 6A also shows a connection electrode 311b electrically connected to the sensor electrode 130X. The connection electrode 311b is electrically connected to a transistor included in the drive circuit 114. A connection portion 330b between the sensor electrode 130X and the connection electrode 311b is provided outside (on the opposite side to the display portion) of a connection portion 330a between the common electrode 313 and the connection electrode 311a.

[0121] Note that the transistor has a function of inputting a pulse voltage to the connection electrode 311b, that is, the connection electrode 311b is electrically connected to the source or drain of the transistor.

[0122] In addition, Figure 6A shows an example in which the conductive layer constituting the sensor electrode 130X extends to the connection portion 330b with the connection electrode 311b, but the conductive layer may be electrically connected to a low-resistance metal layer, and the metal layer may be electrically connected to the connection electrode 311b.

[0123] Fig. 6B is a schematic cross-sectional view corresponding to dashed dotted lines A1-A2, B1-B2, and C1-C2 shown in Fig. 6A, showing a schematic cross-sectional view of light-emitting device 90G, light-emitting device 90B, connection electrode 311a, and connection electrode 311b provided on insulating layer 301.

[0124] The light-emitting device 90R, which is not shown in the schematic cross-sectional view, can have the same configuration as the light-emitting device 90G or the light-emitting device 90B.

[0125] The light-emitting device 90G has a pixel electrode 311, an organic layer 312G, and a common electrode 313. The light-emitting device 90B has a pixel electrode 311, an organic layer 312B, and a common electrode 313. The common electrode 313 is provided in common to the light-emitting devices 90G and 90B. The pixel electrodes 311 are provided spaced apart from each other between the light-emitting devices.

[0126] The organic layer 312G contains a light-emitting organic compound having at least a peak wavelength in the green wavelength range, and the organic layer 312B contains a light-emitting organic compound having at least a peak wavelength in the blue wavelength range. The organic layer 312G and the organic layer 312B can also be called EL layers.

[0127] Furthermore, the organic layer 312G and the organic layer 312B may each have one or more of an electron injection layer, an electron transport layer, a hole injection layer, and a hole transport layer.

[0128] Here, it is preferable that the uppermost layer of the stacked structure of organic layer 312G and organic layer 312B, i.e., the layer in contact with common electrode 313, is a layer other than the light-emitting layer. For example, it is preferable that an electron injection layer, electron transport layer, hole injection layer, hole transport layer, or a layer other than these is provided to cover the light-emitting layer, and that layer is in contact with common electrode 313. In this way, when fabricating each light-emitting device, the reliability of the light-emitting device can be improved by protecting the top surface of the light-emitting layer with another layer.

[0129] The pixel electrode 311 is provided for each light-emitting device. The common electrode 313 is provided as a continuous layer common to each light-emitting device. A conductive film that is transparent to visible light is used for either the pixel electrode 311 or the common electrode 313, and a conductive film that is reflective is used for the other. By making each pixel electrode transparent and the common electrode 313 reflective, a bottom-emission display device can be obtained. Conversely, by making each pixel electrode reflective and the common electrode 313 transparent, a top-emission display device can be obtained. Note that by making both each pixel electrode and the common electrode 313 transparent, a dual-emission display device can also be obtained.

[0130] An insulating layer 340 is provided to cover the end of the pixel electrode 311. The end of the insulating layer 340 is preferably tapered. In this specification and the like, a tapered end of an object means that the angle formed between the surface and the surface on which the object is formed in the end region is greater than 0 degrees and less than 90 degrees, and the object has a cross-sectional shape in which the thickness increases continuously from the end.

[0131] Furthermore, by using an organic resin for the insulating layer 340, the surface can be made gently curved, which improves the coverage of the film formed on the insulating layer 340.

[0132] Materials that can be used for the insulating layer 340 include, for example, acrylic resin, polyimide resin, epoxy resin, polyamide resin, polyimideamide resin, siloxane resin, benzocyclobutene resin, phenol resin, and precursors of these resins.

[0133] Alternatively, an inorganic insulating material may be used for the insulating layer 340. Examples of inorganic insulating materials that can be used for the insulating layer 340 include oxides or nitrides such as silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, aluminum oxide, aluminum oxynitride, and hafnium oxide. In addition, yttrium oxide, zirconium oxide, gallium oxide, tantalum oxide, magnesium oxide, lanthanum oxide, cerium oxide, neodymium oxide, and the like may also be used.

[0134] As shown in Figure 6B, between light-emitting devices emitting different colors of light, the two organic layers are spaced apart, with a gap between them. In this manner, it is preferable that organic layer 312G and organic layer 312B are arranged so that they do not contact each other. This effectively prevents current from flowing through the two adjacent organic layers, which would otherwise cause unintended light emission. This allows for increased contrast and a display device with high display quality.

[0135] The end portions of organic layer 312G and organic layer 312B preferably have a taper angle of 30 degrees or more. The angle between the side surface (surface) and the bottom surface (surface to be formed) at each end portion of organic layer 312G and organic layer 312B is preferably 30 degrees or more and 120 degrees or less, more preferably 45 degrees or more and 120 degrees or less, and even more preferably 60 degrees or more and 120 degrees or less. Alternatively, the taper angle of organic layer 312G and organic layer 312B is preferably 90 degrees or nearly so (for example, 80 degrees or more and 100 degrees or less).

[0136] A protective layer 321 is provided on the common electrode 313. The protective layer 321 has a function of preventing impurities such as water from diffusing from above into each light-emitting device.

[0137] The protective layer 321 may have, for example, a single-layer structure or a multilayer structure including at least an inorganic insulating film. Examples of the inorganic insulating film include oxide films or nitride films such as a silicon oxide film, a silicon oxynitride film, a silicon nitride oxide film, a silicon nitride film, an aluminum oxide film, an aluminum oxynitride film, and a hafnium oxide film. Alternatively, the protective layer 321 may be made of a semiconductor material such as indium gallium oxide or indium gallium zinc oxide.

[0138] The protective layer 321 may also be a laminated film of an inorganic insulating film and an organic insulating film. For example, a configuration in which an organic insulating film is sandwiched between a pair of inorganic insulating films is preferable. Furthermore, it is preferable that the organic insulating film functions as a planarizing film. This allows the upper surface of the organic insulating film to be flat, improving the coverage of the inorganic insulating film thereon and enhancing the barrier properties. Furthermore, when a structure (e.g., an antenna, a touch sensor electrode, a color filter, a lens array, etc.) is provided above the protective layer 321, it is preferable to reduce the influence of uneven shapes caused by the structure below.

[0139] 6B shows an example in which an insulating layer 322 functioning as a planarizing film is provided on a protective layer 321, and sensor electrodes 130X and 130Y functioning as electrodes of a touch sensor are provided on the insulating layer 322. Note that the insulating layer 322 may also function as a solid sealing layer to improve the reliability of the light-emitting device. Furthermore, the layer corresponding to the insulating layer 322 is not limited to one layer, and may be formed of multiple layers.

[0140] 6B shows an example in which the sensor electrodes 130X and 130Y are formed of a translucent conductive film. When the sensor electrodes 130X and 130Y are formed of a lattice-shaped metal conductive film or the like, it is preferable to form them in positions that do not overlap with the light-emitting devices 90G and 90B or in positions where the overlapping area is minimized, as shown in FIG. 6C.

[0141] In the connection portion 330a, a common electrode 313 is provided in contact with the connection electrode 311a, and a protective layer 321 is provided to cover the common electrode 313. An insulating layer 340 is provided to cover the end of the connection electrode 311a.

[0142] At the connection portion 330b, the connection electrode 311b and the sensor electrode 130X are electrically connected via an opening provided in the insulating layer 322 and the protective layer 321. Here, since the sensor electrode 130X may be made of a material with a relatively high resistance, it is preferable to provide a metal layer 315 between the sensor electrode 130X and the connection electrode 311b. By providing the metal layer 315, it is possible to reduce the contact resistance between the sensor electrode 130X and the connection electrode 311b.

[0143] If contact resistance is not an issue, the sensor electrode 130 and the connection electrode 311b may be in direct contact with each other as shown in Fig. 6D. Alternatively, the insulating layer 322 may not be provided near the connection portion 330b as shown in Fig. 6E.

[0144] An example of the configuration of a display device that is partially different from that shown in Fig. 6B will be described below. Specifically, an example in which the insulating layer 340 is not provided will be described.

[0145] FIG. 7A shows an example in which the side surface of the pixel electrode 311 and the side surface of the organic layer 312G or the organic layer 312B are substantially aligned.

[0146] 7A , an insulating layer 325 is provided in contact with the side surfaces of the organic layer 312G, the organic layer 312B, and the pixel electrode 311. The insulating layer 325 can effectively prevent an electrical short circuit between the pixel electrode 311 and the common electrode 313 and a leakage current between them.

[0147] The insulating layer 325 can be an insulating layer containing an inorganic material. For example, an inorganic insulating film such as an insulating oxide film, a nitride insulating film, an oxynitride insulating film, or a nitride oxide insulating film can be used for the insulating layer 325. The insulating layer 325 may have a single-layer structure or a stacked-layer structure. Examples of oxide insulating films include a silicon oxide film, an aluminum oxide film, a magnesium oxide film, an indium gallium zinc oxide film, a gallium oxide film, a germanium oxide film, an yttrium oxide film, a zirconium oxide film, a lanthanum oxide film, a neodymium oxide film, a hafnium oxide film, and a tantalum oxide film. Examples of nitride insulating films include a silicon nitride film and an aluminum nitride film. Examples of oxynitride insulating films include a silicon oxynitride film and an aluminum oxynitride film. Examples of nitride oxide insulating films include a silicon nitride oxide film and an aluminum nitride oxide film. In particular, by using an inorganic insulating film such as an aluminum oxide film, a hafnium oxide film, or a silicon oxide film formed by an ALD method as the insulating layer 325, an insulating layer 325 with few pinholes and excellent protection of the organic layer can be formed.

[0148] In this specification and elsewhere, an oxynitride refers to a material whose composition contains more oxygen than nitrogen, and a nitride oxide refers to a material whose composition contains more nitrogen than oxygen. For example, silicon oxynitride refers to a material whose composition contains more oxygen than nitrogen, and silicon nitride oxide refers to a material whose composition contains more nitrogen than oxygen.

[0149] The insulating layer 325 can be formed by a sputtering method, a CVD method, a PLD method, an ALD method, or the like. The insulating layer 325 is preferably formed by an ALD method because it has good coverage.

[0150] Furthermore, a resin layer 326 is provided between two adjacent light-emitting devices so as to fill the gap between two opposing pixel electrodes and the gap between two opposing organic layers. The resin layer 326 can flatten the surface on which the common electrode 313 and other components are formed, thereby preventing the common electrode 313 from being broken due to insufficient coverage of the step between adjacent light-emitting devices.

[0151] An insulating layer containing an organic material can be suitably used as the resin layer 326. For example, acrylic resin, polyimide resin, epoxy resin, imide resin, polyamide resin, polyimideamide resin, silicone resin, siloxane resin, benzocyclobutene-based resin, phenolic resin, and precursors of these resins can be used as the resin layer 326. Alternatively, organic materials such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinylpyrrolidone, polyethylene glycol, polyglycerin, pullulan, water-soluble cellulose, and alcohol-soluble polyamide resin can be used as the resin layer 326. Alternatively, a photosensitive resin can be used as the resin layer 326. A photoresist can be used as the photosensitive resin. The photosensitive resin can be a positive-type material or a negative-type material.

[0152] Furthermore, it is preferable to use a material that absorbs visible light for the resin layer 326. When a material that absorbs visible light is used for the resin layer 326, light emitted from the EL layer can be absorbed by the resin layer 326, stray light from adjacent pixels can be blocked, and color mixing can be suppressed. Therefore, a display device with high display quality can be provided.

[0153] Since an insulating layer 325 is provided between the resin layer 326 and the organic layer 312G, etc., impurities such as moisture contained in the resin layer 326 can be prevented from diffusing into the organic layer 312G, etc., resulting in a highly reliable display device.

[0154] In addition, a reflective film (e.g., a metal film containing one or more selected from silver, palladium, copper, titanium, aluminum, etc.) may be provided between the insulating layer 325 and the resin layer 326, and a mechanism for improving the light extraction efficiency may be provided by reflecting the light emitted from the light-emitting layer with the reflective film.

[0155] 7B shows an example in which the width of the pixel electrode 311 is larger than the width of the organic layer 312G or the organic layer 312B. The organic layer 312G and the like are provided inside the edge of the pixel electrode 311.

[0156] The insulating layer 325 is provided to cover the side surfaces of the organic layers of the light-emitting devices and part of the top surface and side surfaces of the pixel electrodes 311. The resin layer 326 is located between two adjacent light-emitting devices and is provided in contact with the insulating layer 325.

[0157] 7C shows an example in which the width of pixel electrode 311 is smaller than the width of organic layer 312G or organic layer 312B. Organic layer 312G or the like extends outward beyond the edge of pixel electrode 311.

[0158] The insulating layer 325 is provided in contact with the side surfaces of the organic layers of two adjacent light-emitting devices. The insulating layer 325 may be provided to cover not only the side surfaces of the organic layer 312G etc. but also part of the top surfaces. The resin layer 326 is located between the two adjacent light-emitting devices and is provided in contact with the insulating layer 325.

[0159] Here, an example of the structure of the resin layer 326 will be described.

[0160] The upper surface of the resin layer 326 is preferably as flat as possible, but the surface of the resin layer 326 may have a concave or convex shape depending on the uneven shape of the surface on which the resin layer 326 is formed, the conditions under which the resin layer 326 is formed, and the like.

[0161] FIG. 7D is an enlarged cross-sectional view showing an example in which the surface of the resin layer 326 has an uneven shape in the configuration of FIG. 7C.

[0162] The ends of the pixel electrode 311G and the pixel electrode 311B have a tapered shape. An organic layer 312G is formed so as to cover the end of the pixel electrode 311G, and an organic layer 312B is formed so as to cover the end of the pixel electrode 311B. The insulating layer 301 has a recess between the pixel electrode 311G and the pixel electrode 311B. The recess is formed when the pixel electrode 311G and the pixel electrode 311B are processed.

[0163] An insulating layer 325 is provided so as to cover the ends of the organic layer 312G and the organic layer 312B, and a protective layer 327G is provided in the region between the organic layer 312G and the insulating layer 325. A protective layer 327B is provided in the region between the organic layer 312B and the insulating layer 325. The protective layer 327G and the protective layer 327B function as masks (also referred to as hard masks) when processing the organic layer 312G and the organic layer 312B, respectively. The organic layer 312G and the organic layer 312B can be formed using an inorganic film, more specifically, an inorganic conductive film (typically, tungsten) or an inorganic insulating film (typically, silicon oxide, silicon nitride, or aluminum oxide).

[0164] Furthermore, a recess is formed in the insulating layer 301 located in the region between the organic layer 312G and the organic layer 312B. The recess is formed when the organic layer 312G and the organic layer 312B are processed.

[0165] The common electrode 313 and the protective layer 321 are provided so as to cover the organic layer 312 G, the organic layer 312 B, the protective layer 327 G, the protective layer 327 B, the insulating layer 325 , and the resin layer 326 .

[0166] When the resin layer 326 has at least a part of an end portion that has a tapered shape in cross section, coverage of the common electrode 313 can be improved, which is preferable.

[0167] Note that the configurations and components illustrated in FIGS. 6A to 6E and 7A to 7D are merely examples, and other configurations can also be used in one embodiment of the present invention.

[0168] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0169] Embodiment 2 This embodiment will describe a vertical transistor that can be used for the driver circuits 112, 113, and 114 and the pixel 120 shown in Embodiment 1. The vertical transistor has a structure that can be easily miniaturized and can operate at high speed.

[0170] 8A and 8B are diagrams illustrating a vertical transistor. Fig. 8A is a top view. Fig. 8B is a cross-sectional perspective view illustrating the depth direction of region d shown in Fig. 8A. Note that for clarity, some elements are omitted in Fig. 8A and Fig. 8B.

[0171] The transistor 100T, which is a vertical transistor, can be provided over a substrate 402. The transistor 100T includes a conductive layer 404, a conductive layer 404e, an insulating layer 406, a semiconductor layer 408, a conductive layer 412a, and a conductive layer 412b. The conductive layer 404 is a gate line and is electrically connected to the conductive layer 404e, which functions as a gate electrode. A part of the insulating layer 406 functions as a gate insulating layer. The conductive layer 412a functions as one of a source electrode and a drain electrode. The conductive layer 412b functions as the other of the source electrode and the drain electrode.

[0172] The entire region of the semiconductor layer 408 that overlaps with the gate electrode between the source electrode and the drain electrode via the gate insulating layer functions as a channel formation region. The region of the semiconductor layer 408 that is in contact with the source electrode functions as a source region, and the region that is in contact with the drain electrode functions as a drain region.

[0173] A conductive layer 412a is provided over a substrate 402, an insulating layer 407 is provided over the conductive layer 412a, and a conductive layer 412b is provided over the insulating layer 407. The insulating layer 407 has a region sandwiched between the conductive layer 412a and the conductive layer 412b. The conductive layer 412a has a region overlapping with the conductive layer 412b with the insulating layer 407 interposed therebetween. The insulating layer 407 and the conductive layer 412b have an opening 441 that reaches the conductive layer 412a.

[0174] The conductive layer 412a and the conductive layer 412b may each have a stacked-layer structure. Figure 8B shows an example in which the conductive layer 412a has a stacked-layer structure of a conductive layer 412a_1 and a conductive layer 412a_2. Note that Figure 8B shows an example in which the conductive layer 412a_1 has a region where the conductive layer 412a_2 is not provided and is in contact with the semiconductor layer 408 in this region. However, the conductive layer 412a_2 and the semiconductor layer 408 may be in contact with each other. Alternatively, the conductive layer 412a_2 may not be provided.

[0175] The top surface shape of the opening 441 can be, for example, circular or elliptical. By making the top surface shape of the opening 441 circular, the processing accuracy when forming the opening 441 can be improved, and the opening 441 can be formed in a fine size. The top surface shape of the opening 441 may be a polygon such as a triangle, a quadrangle (including a rectangle, a diamond, and a square), or a pentagon, or a polygon with rounded corners. The opening 441 can be formed using, for example, a resist mask.

[0176] The semiconductor layer 408 is provided to cover the opening 441. The semiconductor layer 408 has regions in contact with the top surface and side surfaces of the conductive layer 412b, the side surfaces of the insulating layer 407, and the top surface of the conductive layer 412a. The semiconductor layer 408 is electrically connected to the conductive layer 412a through the opening 441. The semiconductor layer 408 has a shape that follows the shapes of the top surface and side surfaces of the conductive layer 412b, the side surfaces of the insulating layer 407, and the top surface of the conductive layer 412a.

[0177] 8B and the like, the semiconductor layer 408 has a single-layer structure; however, one embodiment of the present invention is not limited to this. The semiconductor layer 408 may have a stacked structure of two or more layers.

[0178] The insulating layer 406 functioning as a gate insulating layer of the transistor 100T is provided over the semiconductor layer 408, the conductive layer 412b, and the insulating layer 407 so as to cover the recessed portion resulting from the opening 441.

[0179] The conductive layer 404e of the transistor 100T is provided over the insulating layer 406 so as to cover a recess resulting from the opening 441. Here, an insulating layer (not shown) is preferably provided over the conductive layer 404e and the insulating layer 406. An opening reaching the conductive layer 404e is provided in the insulating layer, and the conductive layer 404 functioning as a gate line is electrically connected to the conductive layer 404e through the opening.

[0180] In the opening 441, the conductive layer 404e has a region overlapping with the semiconductor layer 408 with the insulating layer 406 interposed therebetween. The conductive layer 404e also has a region overlapping with the conductive layer 412a with the insulating layer 406 and the semiconductor layer 408 interposed therebetween and a region overlapping with the conductive layer 412b. The conductive layer 404e preferably covers an end portion of the conductive layer 412b on the opening 441 side. With this structure, the entire region of the semiconductor layer 408 that overlaps with the gate electrode with the gate insulating layer interposed therebetween can function as a channel formation region between the source electrode and the drain electrode.

[0181] The transistor 100T is a so-called top-gate transistor having a gate electrode above the semiconductor layer 408. Furthermore, since the bottom surface of the semiconductor layer 408 is in contact with the source electrode or the drain electrode, the transistor 100T can be called a TGBC (Top Gate Bottom Contact) transistor.

[0182] The conductive layers 412a, 412b, and 404 can each function as wirings, and the transistor 100T can be provided in a region where these wirings overlap. That is, in a circuit including the transistor 100T and the wirings, the area occupied by the transistor 100T and the wirings can be reduced. Therefore, the area occupied by the circuit can be reduced.

[0183] In the transistor of one embodiment of the present invention, the conductive layers 412a, 412b, and 404, which function as wirings, can be formed by processing different conductive films. Therefore, one or more other conductive layers can be arranged to overlap any one of the conductive layers, which increases the flexibility of the layout and enables the area occupied by the circuit to be reduced.

[0184] Next, the channel length and the channel width of the transistor 100T will be described. In the semiconductor layer 408, a region in contact with the conductive layer 412a functions as one of a source region and a drain region, a region in contact with the conductive layer 412b functions as the other of the source region and the drain region, and a region between the source region and the drain region functions as a channel formation region.

[0185] The channel length of the transistor 100T is the distance between the source region and the drain region. In Figure 8B, the channel length L100 of the transistor 100T is indicated by a dashed double-headed arrow. The channel length L100 is the distance between the edge of the region where the semiconductor layer 408 and the conductive layer 412a contact each other and the edge of the region where the semiconductor layer 408 and the conductive layer 412b contact each other in a cross-sectional view.

[0186] In other words, the channel length L100 is determined by the film thickness of the insulating layer 407 and the angle formed between the side surface of the insulating layer 407 on the opening 441 side and the upper surface of the conductive layer 412a, and is not affected by the performance of the exposure equipment used to fabricate the transistor. Therefore, the channel length L100 can be set to a value smaller than the limit resolution of the exposure equipment, and a transistor with a fine size can be realized.

[0187] By reducing the channel length L100, the on-state current of the transistor 100T can be increased. By using the transistor 100T, a circuit capable of high-speed operation can be manufactured. Furthermore, the transistor can be miniaturized, which allows the occupied area of ​​the circuit to be reduced.

[0188] 8B and the like show a cross-sectional view in which the side surface of the insulating layer 407 on the opening 441 side has a straight line shape; however, one embodiment of the present invention is not limited to this. In a cross-sectional view, the side surface of the insulating layer 407 on the opening 441 side may have a curved line shape, or the side surface may have both a straight line region and a curved line region.

[0189] The channel width of the transistor 100T is the width of the source region or the width of the drain region in a direction perpendicular to the channel length direction. That is, the channel width is the width of the region where the semiconductor layer 408 and the conductive layer 412a contact each other or the width of the region where the semiconductor layer 408 and the conductive layer 412b contact each other in a direction perpendicular to the channel length direction. Here, the channel width of the transistor 100T is described as the width of the region where the semiconductor layer 408 and the conductive layer 412b contact each other in a direction perpendicular to the channel length direction. In Figures 8A and 8B, the channel width W100 of the transistor 100T is indicated by a solid double-headed arrow. The channel width W100 is the length of the bottom end of the conductive layer 412b on the opening 441 side in a top view.

[0190] The channel width W100 is determined by the top surface shape of the opening 441. When the top surface shape of the opening 441 is circular, the diameter of the opening 441 is set to D441, and the film thickness of the conductive layer 412b is assumed to be negligible, then the channel width W100 can be calculated as "D441 × π".

[0191] That is, the transistor 100T has a large channel width relative to its occupied area. By increasing the channel width W100, the on-state current of the transistor 100T can be increased, and a circuit capable of high-speed operation can be manufactured.

[0192] 9A and 9B are diagrams illustrating an example in which a back gate is added to the configurations of FIGS. 8A and 8B. The conductive layer 415 serving as the back gate electrode is provided so as to be embedded in the insulating layer 407 (insulating layers 407a and 407c), and part of the insulating layer 407c provided between the semiconductor layer 408 and the conductive layer 415 functions as a gate insulating layer. Note that an insulating layer different from the insulating layer 407c may be used as the gate insulating layer.

[0193] The components included in the transistor 100T of this embodiment will be described below.

[0194] [Components of Transistor] [Semiconductor Layer 408] The semiconductor material that can be used for the semiconductor layer 408 is not particularly limited. For example, an elemental semiconductor or a compound semiconductor can be used. As the elemental semiconductor, for example, silicon or germanium can be used. As the compound semiconductor, for example, gallium arsenide and silicon germanium can be used. As the compound semiconductor, an organic substance having semiconductor properties or a metal oxide (also called an oxide semiconductor) having semiconductor properties can be used. Note that these semiconductor materials may contain impurities as dopants.

[0195] The crystallinity of the semiconductor material used for the semiconductor layer 408 is not particularly limited, and any of an amorphous semiconductor and a crystalline semiconductor (a single-crystalline semiconductor, a polycrystalline semiconductor, a microcrystalline semiconductor, or a semiconductor having a crystalline region in part) may be used. Use of a crystalline semiconductor is preferable because it can suppress deterioration of transistor characteristics.

[0196] The semiconductor layer 408 preferably includes a metal oxide (oxide semiconductor). Examples of metal oxides that can be used for the semiconductor layer 408 include indium oxide, gallium oxide, and zinc oxide. The metal oxide preferably includes at least indium (In) or zinc (Zn). The metal oxide preferably includes two or three elements selected from indium, element M, and zinc. The element M is one or more elements selected from gallium, aluminum, silicon, boron, yttrium, tin, antimony, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, cobalt, and magnesium. In particular, the element M is preferably one or more elements selected from aluminum, gallium, yttrium, and tin. Gallium is more preferred as the element M.

[0197] The semiconductor layer 408 can be formed using, for example, indium oxide, indium gallium oxide (In—Ga oxide), indium zinc oxide (In—Zn oxide), indium tin oxide (In—Sn oxide), indium titanium oxide (In—Ti oxide), gallium zinc oxide (Ga—Zn oxide), indium aluminum zinc oxide (In—Al—Zn oxide, also referred to as IAZO), indium tin zinc oxide (In—Sn—Zn oxide), indium titanium zinc oxide (In—Ti—Zn oxide), indium gallium zinc oxide (In—Ga—Zn oxide, also referred to as IGZO), indium gallium tin zinc oxide (In—Ga—Sn—Zn oxide, also referred to as IGZTO), indium gallium aluminum zinc oxide (In—Ga—Al—Zn oxide, also referred to as IGAZO or IAGZO), or the like. Alternatively, indium tin oxide containing silicon can be used.

[0198] Here, the composition of the metal oxide in the semiconductor layer 408 greatly affects the electrical characteristics and reliability of the transistor 100T. For example, by increasing the ratio of the number of indium atoms to the total number of atoms of all metal elements contained in the metal oxide, a transistor with a large on-state current can be realized.

[0199] When an In—Zn oxide is used for the semiconductor layer 408, it is preferable to use a metal oxide in which the atomic ratio of indium is equal to or greater than the atomic ratio of zinc. For example, a metal oxide in which the atomic ratio of metal elements is In:Zn=1:1, In:Zn=2:1, In:Zn=3:1, In:Zn=4:1, In:Zn=5:1, In:Zn=7:1, or In:Zn=10:1, or a ratio close to these, can be used.

[0200] When an In—Sn oxide is used for the semiconductor layer 408, it is preferable to use a metal oxide in which the atomic ratio of indium is equal to or greater than the atomic ratio of tin. For example, a metal oxide in which the atomic ratio of metal elements is In:Sn=1:1, In:Sn=2:1, In:Sn=3:1, In:Sn=4:1, In:Sn=5:1, In:Sn=7:1, or In:Sn=10:1, or a ratio close to these values, can be used.

[0201] When an In—Sn—Zn oxide is used for the semiconductor layer 408, a metal oxide in which the atomic ratio of indium is higher than the atomic ratio of tin can be used. Furthermore, it is preferable to use a metal oxide in which the atomic ratio of zinc is higher than the atomic ratio of tin. For example, the atomic ratios of metal elements may be In:Sn:Zn=2:1:3, In:Sn:Zn=3:1:2, In:Sn:Zn=4:2:3, In:Sn:Zn=4:2:4.1, In:Sn:Zn=5:1:3, In:Sn:Zn=5:1:6, In:Sn:Zn=5:1:7, In:Sn:Zn=5:1:8, In:Sn:Zn=6:1:6, In :Sn:Zn=10:1:3, In:Sn:Zn=10:1:6, In:Sn:Zn=10:1:7, In:Sn:Zn=10:1:8, In:Sn:Zn=5:2:5, In:Sn:Zn=10:1:10, In:Sn:Zn=20:1:10, In:Sn:Zn=40:1:10, or metal oxides thereof having a ratio close to these can be used.

[0202] When an In-Al-Zn oxide is used for the semiconductor layer 408, a metal oxide in which the atomic ratio of indium is higher than that of aluminum can be used. Furthermore, it is preferable to use a metal oxide in which the atomic ratio of zinc is higher than that of aluminum. For example, the atomic ratios of metal elements may be In:Al:Zn=2:1:3, In:Al:Zn=3:1:2, In:Al:Zn=4:2:3, In:Al:Zn=4:2:4.1, In:Al:Zn=5:1:3, In:Al:Zn=5:1:6, In:Al:Zn=5:1:7, In:Al:Zn=5:1:8, In:Al:Zn=6:1:6, In In:Al:Zn=10:1:3, In:Al:Zn=10:1:6, In:Al:Zn=10:1:7, In:Al:Zn=10:1:8, In:Al:Zn=5:2:5, In:Al:Zn=10:1:10, In:Al:Zn=20:1:10, In:Al:Zn=40:1:10, or metal oxides thereof having a similar ratio can be used.

[0203] When an In—Ga—Zn oxide is used for the semiconductor layer 408, a metal oxide in which the atomic ratio of indium to the sum of the atomic numbers of all contained metal elements is higher than the atomic ratio of gallium can be used. Furthermore, it is more preferable to use a metal oxide in which the atomic ratio of zinc is higher than the atomic ratio of gallium. For example, the semiconductor layer 408 may have an atomic ratio of metal elements of In:Ga:Zn=2:1:3, In:Ga:Zn=3:1:2, In:Ga:Zn=4:2:3, In:Ga:Zn=4:2:4.1, In:Ga:Zn=5:1:3, In:Ga:Zn=5:1:6, In:Ga:Zn=5:1:7, In:Ga:Zn=5:1:8, or In:Ga:Zn=6:1. :6, In:Ga:Zn=10:1:3, In:Ga:Zn=10:1:6, In:Ga:Zn=10:1:7, In:Ga:Zn=10:1:8, In:Ga:Zn=5:2:5, In:Ga:Zn=10:1:10, In:Ga:Zn=20:1:10, In:Ga:Zn=40:1:10, or metal oxides thereof can be used.

[0204] When an In-M-Zn oxide is used for the semiconductor layer 408, a metal oxide can be used in which the atomic ratio of indium to the sum of the atomic numbers of all contained metal elements is higher than the atomic ratio of element M. Furthermore, it is more preferable to use a metal oxide in which the atomic ratio of zinc is higher than the atomic ratio of element M. For example, the semiconductor layer 408 may have atomic ratios of metal elements of In:M:Zn=2:1:3, In:M:Zn=3:1:2, In:M:Zn=4:2:3, In:M:Zn=4:2:4.1, In:M:Zn=5:1:3, In:M:Zn=5:1:6, In:M:Zn=5:1:7, In:M:Zn=5:1:8, In:M:Zn=6:1: In:M:Zn=10:1:6, In:M:Zn=10:1:3, In:M:Zn=10:1:6, In:M:Zn=10:1:7, In:M:Zn=10:1:8, In:M:Zn=5:2:5, In:M:Zn=10:1:10, In:M:Zn=20:1:10, In:M:Zn=40:1:10, or metal oxides thereof having a similar structure can be used.

[0205] By increasing the indium content of the metal oxide, a transistor with a large on-state current can be obtained. By applying the transistor to a transistor that requires a high on-state current, a circuit with excellent electrical characteristics can be formed.

[0206] The composition of the metal oxide can be analyzed by, for example, energy dispersive X-ray spectrometry (EDX), X-ray photoelectron spectrometry (XPS), inductively coupled plasma mass spectrometry (ICP-MS), or inductively coupled plasma atomic emission spectrometry (ICP-AES). Alternatively, a combination of these techniques may be used for the analysis. For elements with low content, the actual content may differ from the content obtained by analysis due to the influence of analytical accuracy. For example, when the content of element M is low, the content of element M obtained by analysis may be lower than the actual content.

[0207] In this specification, a "nearby composition" includes a range of ±30% of the desired atomic ratio. For example, when an atomic ratio is described as In:M:Zn = 4:2:3 or a composition thereabout, this includes a case where, when the atomic ratio of indium is 4, the atomic ratio of M is 1 or more and 3 or less, and the atomic ratio of zinc is 2 or more and 4 or less. Furthermore, when an atomic ratio is described as In:M:Zn = 5:1:6 or a composition thereabout, this includes a case where, when the atomic ratio of indium is 5, the atomic ratio of M is more than 0.1 and 2 or less, and the atomic ratio of zinc is 5 or more and 7 or less. Furthermore, when an atomic ratio is described as In:M:Zn = 1:1:1 or a composition thereabout, this includes a case where, when the atomic ratio of indium is 1, the atomic ratio of M is more than 0.1 and 2 or less, and the atomic ratio of zinc is more than 0.1 and 2 or less.

[0208] The metal oxide can be preferably formed by sputtering or atomic layer deposition (ALD). When forming a metal oxide by sputtering, the atomic ratio of the target may differ from the atomic ratio of the metal oxide. In particular, the atomic ratio of zinc in the metal oxide may be smaller than the atomic ratio of the target. Specifically, the atomic ratio of zinc in the metal oxide may be approximately 40% to 90% of the atomic ratio of zinc contained in the target.

[0209] The semiconductor layer 408 may have a stacked structure including two or more metal oxide layers. The two or more metal oxide layers included in the semiconductor layer 408 may have the same or approximately the same composition. By using a stacked structure of metal oxide layers having the same composition, for example, the same sputtering target can be used for formation, thereby reducing manufacturing costs.

[0210] The two or more metal oxide layers included in the semiconductor layer 408 may have different compositions. For example, a stacked structure of a first metal oxide layer having an atomic ratio of In:M:Zn=1:3:4 or a composition similar thereto and a second metal oxide layer having an atomic ratio of In:M:Zn=1:1:1 or a composition similar thereto, provided on the first metal oxide layer, can be preferably used. Furthermore, it is particularly preferable to use gallium or aluminum as the element M. For example, a stacked structure of any one selected from indium oxide, indium gallium oxide, and IGZO and any one selected from IAZO, IAGZO, and ITZO (registered trademark) can be used.

[0211] A crystalline metal oxide layer is preferably used for the semiconductor layer 408. For example, a metal oxide layer having a c-axis aligned crystal (CAAC) structure, a polycrystalline structure, a nanocrystalline (nc) structure, or the like can be used. By using a crystalline metal oxide layer for the semiconductor layer 408, the density of defect states in the semiconductor layer 408 can be reduced, and a highly reliable transistor can be realized.

[0212] The higher the crystallinity of the metal oxide layer used for the semiconductor layer 408, the more the density of defect states in the semiconductor layer 408 can be reduced. On the other hand, by using a metal oxide layer with low crystallinity, a transistor capable of passing a large current can be realized.

[0213] The semiconductor layer 408 may have a stacked structure of two or more metal oxide layers with different crystallinity. For example, the semiconductor layer 408 may have a stacked structure of a first metal oxide layer and a second metal oxide layer provided on the first metal oxide layer, where the second metal oxide layer has a region with higher crystallinity than the first metal oxide layer. Alternatively, the second metal oxide layer may have a region with lower crystallinity than the first metal oxide layer. The two or more metal oxide layers included in the semiconductor layer 408 may have the same or approximately the same composition. By using a stacked structure of metal oxide layers with the same composition, for example, the same sputtering target can be used to form the layers, thereby reducing manufacturing costs. For example, by using the same sputtering target and varying the oxygen flow rate, a stacked structure of two or more metal oxide layers with different crystallinity can be formed. Note that the two or more metal oxide layers included in the semiconductor layer 408 may have different compositions.

[0214] In the case where an oxide semiconductor is used for the semiconductor layer 408, the carrier concentration of the oxide semiconductor in a region functioning as a channel formation region is 1×10 １８ cm −３ Preferably, it is 1×10 or less. １７ cm −３ More preferably, it is less than 1×10 １６ cm −３ More preferably, it is less than 1×10 １３ cm −３ More preferably, it is less than 1×10 １２ cm −３ The lower limit of the carrier concentration of the oxide semiconductor in the region functioning as a channel formation region is not particularly limited, but is preferably, for example, 1×10 −９ cm −３ It can be said that:

[0215] A transistor using an oxide semiconductor (hereinafter referred to as an OS transistor) has significantly higher field-effect mobility than a transistor using amorphous silicon. Furthermore, an OS transistor has significantly lower source-drain leakage current in an off state (hereinafter also referred to as off-state current) and can hold charge accumulated in a capacitor connected in series with the transistor for a long period of time. Furthermore, the use of an OS transistor can reduce the power consumption of a semiconductor device.

[0216] [Insulating Layer 407] When an oxide semiconductor is used for the semiconductor layer 408, an inorganic insulating material can be suitably used for the insulating layer 407 (the insulating layer 407a, the insulating layer 407b, and the insulating layer 407c). Note that the insulating layer 407 may have a stacked structure of an inorganic insulating material and an organic insulating material.

[0217] The inorganic insulating material can be one or more of oxide, oxynitride, nitride oxide, and nitride. For example, the insulating layer 407 can be one or more of silicon oxide, silicon oxynitride, aluminum oxide, hafnium oxide, yttrium oxide, zirconium oxide, gallium oxide, tantalum oxide, magnesium oxide, lanthanum oxide, cerium oxide, neodymium oxide, silicon nitride, silicon nitride oxide, and aluminum nitride.

[0218] In this specification and the like, an oxynitride refers to a material whose composition contains more oxygen than nitrogen. A nitride oxide refers to a material whose composition contains more nitrogen than oxygen. For example, silicon oxynitride refers to a material whose composition contains more oxygen than nitrogen, and silicon nitride oxide refers to a material whose composition contains more nitrogen than oxygen.

[0219] The insulating layer 407b is preferably formed using an oxide or an oxynitride. The insulating layer 407b is preferably formed using a film that releases oxygen when heated. For example, silicon oxide or silicon oxynitride can be suitably used for the insulating layer 407b.

[0220] When the insulating layer 407b releases oxygen, oxygen can be supplied from the insulating layer 407b to the semiconductor layer 408. When oxygen is supplied from the insulating layer 407b to the semiconductor layer 408, particularly to the channel formation region of the semiconductor layer 408, oxygen vacancies (V Ｏ ) and V Ｏ H (defects in which hydrogen enters oxygen vacancies) can be reduced, resulting in a transistor with good electrical characteristics and high reliability. The insulating layer 407b preferably has a high oxygen diffusion coefficient. By increasing the oxygen diffusion coefficient of the insulating layer 407b, oxygen can be easily diffused in the insulating layer 407b, and oxygen can be efficiently supplied from the insulating layer 407b to the semiconductor layer 408. Other treatments for supplying oxygen to the semiconductor layer 408 include heat treatment in an atmosphere containing oxygen and plasma treatment in an atmosphere containing oxygen.

[0221] Oxygen vacancies in the channel formation region of the transistor 100T (V Ｏ ) and V Ｏ In particular, when the channel length L100 is short, oxygen vacancies (V Ｏ ) and V Ｏ For example, if VH is introduced from the source or drain region to the channel forming region, the influence of VH on the electrical characteristics and reliability will increase. Ｏ The diffusion of H increases the carrier concentration in the channel formation region, which may cause a fluctuation in the threshold voltage of the transistor 100T or a decrease in reliability. Ｏ The influence of the diffusion of H on the electrical characteristics and reliability becomes greater as the channel length L100 of the transistor 100T becomes shorter. By supplying oxygen from the insulating layer 407b to the semiconductor layer 408, particularly to the channel formation region of the semiconductor layer 408, oxygen vacancies (V Ｏ ) and V Ｏ H can be reduced. Therefore, a transistor having a short channel length and having good electrical characteristics and high reliability can be realized.

[0222] The insulating layers 407a and 407c are preferably impermeable to oxygen. The insulating layers 407a and 407c function as blocking films that prevent oxygen from being released from the insulating layer 407b. Furthermore, the insulating layers 407a and 407c are preferably impermeable to hydrogen. The insulating layers 407a and 407c function as blocking films that prevent hydrogen from diffusing from the outside of the transistor to the semiconductor layer 408 through the insulating layer 407. The insulating layers 407a and 407c preferably have high film densities. Increasing the film densities of the insulating layers 407a and 407c can improve the blocking properties of oxygen and hydrogen. The film densities of the insulating layers 407a and 407c are preferably higher than that of the insulating layer 407b. When silicon oxide or silicon oxynitride is used for the insulating layer 407b, the insulating layers 407a and 407c can each preferably be made of, for example, silicon nitride, silicon nitride oxide, or aluminum oxide. The insulating layers 407a and 407c each preferably have a region containing more nitrogen than the insulating layer 407b. The insulating layers 407a and 407c can each be made of, for example, a material containing more nitrogen than the insulating layer 407b. The insulating layers 407a and 407c can each preferably be made of, for example, nitride or nitride oxide. The insulating layers 407a and 407c can each be made of, for example, silicon nitride or silicon nitride oxide.

[0223] When oxygen contained in the insulating layer 407b diffuses upward from a region of the insulating layer 407b that is not in contact with the semiconductor layer 408 (for example, the upper surface of the insulating layer 407b), the amount of oxygen supplied from the insulating layer 407b to the semiconductor layer 408 may decrease. By providing the insulating layer 407c on the insulating layer 407b, it is possible to prevent the oxygen contained in the insulating layer 407b from diffusing from a region of the insulating layer 407 that is not in contact with the semiconductor layer 408. Similarly, by providing the insulating layer 407a below the insulating layer 407b, it is possible to prevent the oxygen from diffusing downward from a region of the insulating layer 407 that is not in contact with the semiconductor layer 408. Therefore, the amount of oxygen supplied from the insulating layer 407b to the semiconductor layer 408 increases, and oxygen vacancies (V Ｏ ) and V Ｏ H can be reduced. Therefore, a highly reliable transistor can be obtained that exhibits favorable electrical characteristics.

[0224] The conductive layer 412a and the conductive layer 412b may be oxidized by oxygen contained in the insulating layer 407b, resulting in an increase in resistance. Furthermore, the conductive layer 412a and the conductive layer 412b may be oxidized by oxygen contained in the insulating layer 407b, resulting in a decrease in the amount of oxygen supplied from the insulating layer 407b to the semiconductor layer 408. By providing the insulating layer 407a between the insulating layer 407b and the conductive layer 412a, the conductive layer 412a may be prevented from being oxidized and the resistance may be reduced. Similarly, by providing the insulating layer 407c between the insulating layer 407b and the conductive layer 412b, the conductive layer 412b may be prevented from being oxidized and the resistance may be reduced. At the same time, the amount of oxygen supplied from the insulating layer 407b to the semiconductor layer 408 increases, resulting in an oxygen deficiency (V Ｏ ) and V Ｏ H can be reduced, and a highly reliable transistor can be obtained that exhibits favorable electrical characteristics.

[0225] When hydrogen diffuses into the semiconductor layer 408, it reacts with oxygen atoms contained in the oxide semiconductor to form water, which causes oxygen vacancies (V Ｏ ) may be formed. ＯBy providing the insulating layers 407a and 407c, oxygen vacancies (V Ｏ ) and V Ｏ H can be reduced, and a highly reliable transistor can be obtained that exhibits favorable electrical characteristics.

[0226] The insulating layers 407a and 407c preferably have thicknesses that allow them to function as blocking films for oxygen and hydrogen. If the insulating layers 407a and 407c are too thin, their function as blocking films may be reduced. On the other hand, if the insulating layers 407a and 407c are too thick, the region of the semiconductor layer 408 in contact with the insulating layer 407b may be narrowed, and the amount of oxygen supplied from the insulating layer 407b to the semiconductor layer 408 may be reduced. The insulating layers 407a and 407c may each be thinner than the insulating layer 407b.

[0227] In the transistor 100T, oxygen is supplied from the insulating layer 407 to the semiconductor layer 408, which reduces oxygen vacancies (V Ｏ ) and V Ｏ Therefore, a transistor having good electrical characteristics and high reliability can be obtained.

[0228] Note that one or both of the insulating layers 407a and 407c may not be provided.

[0229] [Conductive Layer 412a, Conductive Layer 412b, Conductive Layer 404e, and Conductive Layer 415] The conductive layers 412a, 412b, 404e, and 415, which function as source electrodes, drain electrodes, and gate electrodes, can be formed using one or more of chromium, copper, aluminum, gold, silver, zinc, tantalum, titanium, tungsten, manganese, nickel, iron, cobalt, molybdenum, and niobium, or an alloy containing one or more of the above metals. The conductive layers 412a, 412b, 404e, and 415 can be formed using a low-resistance conductive material containing one or more of copper, silver, gold, and aluminum. Copper and aluminum are particularly preferred because of their excellent mass productivity.

[0230] A metal oxide film (also referred to as an oxide conductor) can be used for each of the conductive layer 412a, the conductive layer 412b, the conductive layer 404e, and the conductive layer 415. Examples of oxide conductors (OC) include In—Sn oxide (ITO), In—W oxide, In—W—Zn oxide, In—Ti oxide, In—Ti—Sn oxide, In—Zn oxide, In—Sn—Si oxide (ITSO), and In—Ga—Zn oxide.

[0231] Here, oxide conductors (OC) will be explained. For example, when oxygen vacancies are formed in a metal oxide having semiconductor properties and hydrogen is added to the oxygen vacancies, a donor level is formed near the conduction band. As a result, the metal oxide becomes more conductive and becomes an electric conductor. A metal oxide that has become an electric conductor can be called an oxide conductor.

[0232] The conductive layers 412a, 412b, 404e, and 415 may each have a stacked structure of a conductive film containing the oxide conductor (metal oxide) and a conductive film containing a metal or an alloy. By using a conductive film containing a metal or an alloy, wiring resistance can be reduced.

[0233] A Cu-X alloy film (X is Mn, Ni, Cr, Fe, Co, Mo, Ta, or Ti) may be applied to each of the conductive layer 412a, the conductive layer 412b, the conductive layer 404e, and the conductive layer 415. By using a Cu-X alloy film, it is possible to process it by a wet etching process, thereby reducing manufacturing costs.

[0234] Note that the conductive layer 412a, the conductive layer 412b, the conductive layer 404e, and the conductive layer 415 may be formed using the same material or different materials.

[0235] Here, the conductive layers 412a and 412b will be specifically described using an example in which the semiconductor layer 408 is formed using a metal oxide.

[0236] When an oxide semiconductor is used for the semiconductor layer 408, the conductive layers 412a and 412b are oxidized by oxygen contained in the semiconductor layer 408, which may increase the resistance. The conductive layers 412a and 412b are oxidized by oxygen contained in the insulating layer 407b, which may increase the resistance. Furthermore, the conductive layers 412a and 412b are oxidized by oxygen contained in the semiconductor layer 408, which may increase the oxygen vacancy (V Ｏ When the conductive layers 412a and 412b are oxidized by oxygen contained in the insulating layer 407b, the amount of oxygen supplied from the insulating layer 407b to the semiconductor layer 408 may decrease.

[0237] The conductive layers 412a and 412b are preferably made of a material that is resistant to oxidation. The conductive layers 412a and 412b are preferably made of an oxide conductor. For example, In—Sn oxide (ITO) or In—Sn—Si oxide (ITSO) can be suitably used. The conductive layer 412a may be made of a nitride conductor. Examples of nitride conductors include tantalum nitride and titanium nitride. The conductive layer 412a may have a stacked structure of the above-mentioned materials.

[0238] By using a material that is not easily oxidized for the conductive layer 412a and the conductive layer 412b, it is possible to prevent the conductive layer 412a and the conductive layer 412b from being oxidized by oxygen contained in the semiconductor layer 408 or oxygen contained in the insulating layer 407b, which can prevent the resistance from increasing. Ｏ ) in the semiconductor layer 408 can be suppressed, and the amount of oxygen supplied from the insulating layer 407b to the semiconductor layer 408 can be increased. Ｏ ) and V Ｏ H can be reduced, and a highly reliable transistor can be obtained that exhibits favorable electrical characteristics.

[0239] Similarly, by using a material that is resistant to oxidation for the conductive layer 412b, an increase in resistance can be suppressed. Note that the conductive layers 412a and 412b may be formed using the same material or different materials.

[0240] The conductive layer 412b has a region in contact with the transistor 100T. By using a material that is not easily oxidized for the conductive layer 412b, oxygen vacancies (V Ｏ ) and V Ｏ H can be reduced.

[0241] As described above, the conductive layers 412a and 412b in contact with the semiconductor layer 408 are preferably made of a material that is resistant to oxidation. However, when a material that is resistant to oxidation is used, the resistance may become high. Since the conductive layers 412a and 412b function as wirings, it is preferable that the resistance be low. Therefore, by using a material that is resistant to oxidation for the conductive layer 412a_1 having a region in contact with the semiconductor layer 408 and using a material with low resistance for the conductive layer 412a_2 not having a region in contact with the semiconductor layer 408, the resistance of the conductive layer 412a can be reduced. Furthermore, oxygen vacancies (V Ｏ ) and V Ｏ H can be reduced, and a highly reliable transistor can be obtained that exhibits favorable electrical characteristics.

[0242] As described above, when the channel length L100 is short, oxygen vacancies (V Ｏ) and V Ｏ By using a material that is not easily oxidized for the conductive layer 412a_1, oxygen vacancies (V Ｏ ) and V Ｏ It is possible to suppress an increase in H. Therefore, a transistor having a short channel length, good electrical characteristics, and high reliability can be realized.

[0243] The conductive layer 412a_1 can preferably be made of one or more of an oxide conductor and a nitride conductor. The conductive layer 412a_2 can preferably be made of a material having lower resistance than the conductive layer 412a_1. The conductive layer 412a_2 can preferably be made of, for example, one or more of copper, aluminum, titanium, tungsten, and molybdenum, or an alloy containing one or more of the above metals. Specifically, the conductive layer 412a_1 can preferably be made of In—Sn—Si oxide (ITSO), and the conductive layer 412a_2 can preferably be made of tungsten.

[0244] Note that the structure of the conductive layer 412a may be determined depending on the wiring resistance required for the conductive layer 412a. For example, when the length of the wiring (conductive layer 412a) is short and the required wiring resistance is relatively high, the conductive layer 412a may have a single-layer structure and may be made of a material that is not easily oxidized. On the other hand, when the length of the wiring (conductive layer 412a) is long and the required wiring resistance is relatively low, it is preferable that the conductive layer 412a have a stacked structure of a material that is not easily oxidized and a material that has low resistance.

[0245] Note that the structure of the conductive layer 412a can be applied to other conductive layers.

[0246] [Insulating Layer 406] The insulating layer 406, which functions as a gate insulating layer, preferably has a low defect density. A low defect density in the insulating layer 406 enables a transistor to exhibit favorable electrical characteristics. Furthermore, the insulating layer 406 preferably has a high withstand voltage. A high withstand voltage of the insulating layer 406 enables a highly reliable transistor.

[0247] The insulating layer 406 can be formed using, for example, one or more of an oxide, an oxynitride, a nitride oxide, and a nitride having insulating properties. The insulating layer 406 can be formed using, for example, one or more of silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, aluminum oxide, aluminum oxynitride, aluminum nitride oxide, aluminum nitride, hafnium oxide, hafnium oxynitride, gallium oxide, gallium oxynitride, yttrium oxide, yttrium oxynitride, and Ga-Zn oxide. The insulating layer 406 can be formed as a single layer or a stacked layer. The insulating layer 406 can be formed as, for example, a stacked layer of an oxide and a nitride.

[0248] In a miniaturized transistor, if the thickness of the gate insulating layer becomes thin, leakage current may increase. By using a material with a high relative dielectric constant (also called a high-k material) for the gate insulating layer, it is possible to reduce the voltage during transistor operation while maintaining the physical film thickness. Examples of high-k materials include gallium oxide, hafnium oxide, zirconium oxide, oxides containing aluminum and hafnium, oxynitrides containing aluminum and hafnium, oxides containing silicon and hafnium, oxynitrides containing silicon and hafnium, and nitrides containing silicon and hafnium.

[0249] The insulating layer 406 preferably releases little impurities (for example, water and hydrogen) from itself. The small amount of impurities released from the insulating layer 406 suppresses diffusion of the impurities into the semiconductor layer 408, thereby enabling a transistor to have good electrical characteristics and high reliability.

[0250] Here, the insulating layer 406 will be specifically described using an example in which a metal oxide is used for the semiconductor layer 408 .

[0251] In order to improve the interface characteristics with the semiconductor layer 408, it is preferable to use an oxide for at least the side of the insulating layer 406 that is in contact with the semiconductor layer 408. For example, one or more of silicon oxide and silicon oxynitride can be suitably used for the insulating layer 406. It is more preferable to use a film that releases oxygen by heating for the insulating layer 406.

[0252] Note that the insulating layer 406 may have a stacked structure. The insulating layer 406 can have a stacked structure of an oxide film on the side in contact with the semiconductor layer 408 and a nitride film on the side in contact with the conductive layer 404e. For example, one or more of silicon oxide and silicon oxynitride can be preferably used as the oxide film. For example, silicon nitride can be preferably used as the nitride film.

[0253] [Substrate 402] There are no significant limitations on the material of the substrate 402, but it must have at least heat resistance sufficient to withstand subsequent heat treatment. For example, a single-crystal semiconductor substrate made of silicon or silicon carbide, a polycrystalline semiconductor substrate, a compound semiconductor substrate such as silicon germanium, an SOI substrate, a glass substrate, a quartz substrate, a sapphire substrate, a ceramic substrate, or an organic resin substrate may be used as the substrate 402. Furthermore, any of these substrates on which semiconductor elements are provided may also be used as the substrate 402. The shape of the semiconductor substrate and the insulating substrate may be circular or rectangular.

[0254] A flexible substrate may be used as the substrate 402, and the transistor 100T and the like may be formed directly on the flexible substrate. Alternatively, a peeling layer may be provided between the substrate 402 and the transistor 100T and the like. The peeling layer can be used to separate a semiconductor device, after a part or all of the semiconductor device is completed thereon, from the substrate 402 and transfer the semiconductor device to another substrate. In this case, the transistor 100T and the like can also be transferred to a substrate with poor heat resistance or a flexible substrate.

[0255] The above is a description of the components of the transistor 100T.

[0256] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0257] Embodiment 3 In this embodiment, a display device according to one embodiment of the present invention will be described.

[0258] FIG. 10 is a cross-sectional view of a display device 100 that is a display device of one embodiment of the present invention.

[0259] Figure 10 shows an example of a cross section of a portion of the region including FPC 118, a portion of the region including driver circuit 112, a portion of the region including driver circuit 113, a portion of the region including display unit 111, a portion of the region including driver circuit 114, and a portion of the region including FPC 119 in the display device 100 shown in Figure 1.

[0260] The display device 100 shown in FIG. 10A has, between the substrate 110 and the substrate 140, a transistor 201, a transistor 202, a transistor 203, a transistor 204, a transistor 205, a light-emitting device 90G that emits green light, a light-emitting device 90B that emits blue light, a sensor electrode 130X, and a sensor electrode 130Y.

[0261] The light-emitting device 90G includes a conductive layer 142a, a conductive layer 146a on the conductive layer 142a, and a conductive layer 149a on the conductive layer 146a. All or some of the conductive layers 142a, 146a, and 149a may be called pixel electrodes.

[0262] Light-emitting device 90G includes conductive layer 142b, conductive layer 146b on conductive layer 142b, and conductive layer 149b on conductive layer 146b.

[0263] The conductive layer 142a is connected to the conductive layer 222b of the transistor 203 through an opening provided in the insulating layer 214. The end of the conductive layer 146a is located outside the end of the conductive layer 142a. The end of the conductive layer 146a and the end of the conductive layer 149a are aligned or approximately aligned. For example, a conductive layer functioning as a reflective electrode can be used for the conductive layer 142a and the conductive layer 146a, and a conductive layer functioning as a transparent electrode can be used for the conductive layer 149a.

[0264] The conductive layers 142b, 146b, and 149b in the light-emitting device 90B are similar to the conductive layers 142a, 146a, and 149a in the light-emitting device 90G, and therefore a detailed description thereof will be omitted.

[0265] Recesses are formed in the conductive layers 142a and 142b so as to cover the openings provided in the insulating layer 214. A layer 148 is buried in the recesses.

[0266] The layer 148 has a function of planarizing the recesses of the conductive layers 142a and 142b. Conductive layers 146a and 146b, which are electrically connected to the conductive layers 142a and 142b, are provided on the conductive layers 142a and 142b and the layer 148. Therefore, the regions overlapping with the recesses of the conductive layers 142a and 142b can also be used as light-emitting regions or light-receiving regions, thereby increasing the aperture ratio of the pixel.

[0267] The layer 148 may be an insulating layer or a conductive layer. Various inorganic insulating materials, organic insulating materials, and conductive materials can be used as appropriate for the layer 148. In particular, the layer 148 is preferably formed using an insulating material, and is particularly preferably formed using an organic insulating material. For example, the organic insulating material that can be used for the resin layer 326 described above can be used for the layer 148.

[0268] A protective layer 321 is provided on the light emitting devices 90G and 90B. A solid sealing layer 150 is provided on the protective layer 321 to protect the light emitting devices.

[0269] The display device 100 is a top-emission type. Light emitted by the light-emitting device is emitted toward the substrate 140. The substrate 140 is preferably made of a material that is highly transparent to visible light. The pixel electrodes contain a material that reflects visible light, and the counter electrode (common electrode 313) contains a material that transmits visible light.

[0270] The transistors 201 to 205 are all formed over a substrate 110. The transistors 203 and 204 can be manufactured using the same material and the same process. The transistors 201, 202, and 205 can be manufactured using the same material and the same process.

[0271] Vertical transistors can be used as the transistors 201, 202, and 205. For details of the vertical transistors, refer to Embodiment 2.

[0272] As shown in FIG. 11, vertical transistors may also be used for the transistors 203 and 204 included in the display portion 111 .

[0273] An insulating layer 211, an insulating layer 213, an insulating layer 215, and an insulating layer 214 are provided over the substrate 110 in this order. A part of the insulating layer 211 functions as a gate insulating layer for each transistor. A part of the insulating layer 213 functions as a gate insulating layer for each transistor. The insulating layer 215 is provided to cover the transistor. The insulating layer 214 is provided to cover the transistor and functions as a planarization layer. Note that the number of gate insulating layers and the number of insulating layers covering the transistors are not limited, and each may be a single layer or two or more layers.

[0274] It is preferable that at least one insulating layer covering the transistor is made of a material that is resistant to the diffusion of impurities such as water and hydrogen. This allows the insulating layer to function as a barrier layer. With this structure, it is possible to effectively prevent impurities from diffusing into the transistor from the outside, thereby improving the reliability of the display device.

[0275] It is preferable to use an inorganic insulating film for each of the insulating layers 211, 213, and 215. Examples of the inorganic insulating film that can be used include a silicon nitride film, a silicon oxynitride film, a silicon oxide film, a silicon nitride oxide film, an aluminum oxide film, and an aluminum nitride film. Alternatively, a hafnium oxide film, an yttrium oxide film, a zirconium oxide film, a gallium oxide film, a tantalum oxide film, a magnesium oxide film, a lanthanum oxide film, a cerium oxide film, and a neodymium oxide film may also be used. Two or more of the above insulating films may also be stacked.

[0276] An organic insulating layer is suitable for the insulating layer 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, polyimideamide resin, siloxane resin, benzocyclobutene-based resin, phenolic resin, and precursors of these resins. The insulating layer 214 may also have a laminated structure of an organic insulating layer and an inorganic insulating layer. The outermost layer of the insulating layer 214 preferably functions as an etching protection layer. This can prevent recesses from being formed in the insulating layer 214 during processing of the conductive layer 142a, the conductive layer 146a, the conductive layer 149a, or the like. Alternatively, recesses may be formed in the insulating layer 214 during processing of the conductive layer 142a, the conductive layer 146a, the conductive layer 149a, or the like.

[0277] The transistor 202 and the transistor 203 each include a conductive layer 221 that functions as a gate, an insulating layer 211 that functions as a gate insulating layer, conductive layers 222a and 222b that function as a source and a drain, a semiconductor layer 231, an insulating layer 213 that functions as a gate insulating layer, and a conductive layer 223 that functions as a gate. Here, the same hatching pattern is applied to multiple layers obtained by processing the same conductive film. The insulating layer 211 is located between the conductive layer 221 and the semiconductor layer 231. The insulating layer 213 is located between the conductive layer 223 and the semiconductor layer 231.

[0278] The structure of the transistor included in the display device of this embodiment is not particularly limited. For example, a vertical transistor, a planar transistor, a fin transistor, a staggered transistor, an inverted staggered transistor, or the like can be used. Furthermore, either a top-gate or bottom-gate transistor structure may be used. Alternatively, a gate may be provided only on one side of a semiconductor layer where a channel is formed, not only on both sides.

[0279] The transistors 202 and 203 have a structure in which a semiconductor layer in which a channel is formed is sandwiched between two gates. The two gates may be connected and the same signal may be supplied to drive the transistors. Alternatively, the transistors may be driven by applying a potential for controlling the threshold voltage to one of the two gates and a potential for driving to the other.

[0280] The crystallinity of a semiconductor material used for a transistor is not particularly limited, and any of an amorphous semiconductor, a single-crystal semiconductor, and a semiconductor having crystallinity other than a single crystal (a microcrystalline semiconductor, a polycrystalline semiconductor, or a semiconductor having a crystalline region in part) may be used. The use of a single-crystal semiconductor or a crystalline semiconductor is preferable because it can suppress deterioration of transistor characteristics.

[0281] The semiconductor layer of the transistor preferably contains a metal oxide (also referred to as an oxide semiconductor). That is, the display device of this embodiment preferably uses an OS transistor using a metal oxide for a channel formation region. For the metal oxide that can be used for the OS transistor, the description in Embodiment 2 can be referred to.

[0282] All of the transistors included in the display device 100 can be OS transistors. Alternatively, all of the transistors included in the display device 100 can be Si transistors. Alternatively, some of the transistors included in the display device 100 can be OS transistors and the rest can be Si transistors.

[0283] Alternatively, an OS transistor may be provided over a Si transistor, or OS transistors may be stacked.

[0284] Examples of silicon include single crystal silicon, polycrystalline silicon, and amorphous silicon. In particular, a transistor having low temperature polysilicon (LTPS) in a semiconductor layer (hereinafter also referred to as an LTPS transistor) can be used. The LTPS transistor has high field-effect mobility and favorable frequency characteristics.

[0285] By using Si transistors such as LTPS transistors, circuits that need to be driven at high frequencies (such as source drivers) can be built on the same substrate as the display unit, which simplifies the external circuits mounted on the display device and reduces component and mounting costs.

[0286] For example, by using both an LTPS transistor and an OS transistor in the display portion 111, a display device with low power consumption and high driving capability can be realized. A configuration in which an LTPS transistor and an OS transistor are combined is sometimes referred to as LTPO. As a more preferred example, it is preferable to use an OS transistor as a transistor that functions as a switch for controlling conduction / non-conduction between wirings, and to use an LTPS transistor as a transistor for controlling current.

[0287] For example, one of the transistors included in the display unit 111 functions as a transistor for controlling the current flowing through the light-emitting device and can also be called a driving transistor. One of the source and drain of the driving transistor is electrically connected to the pixel electrode of the light-emitting device. It is preferable to use an LTPS transistor as the driving transistor. This allows the current flowing through the light-emitting device in the pixel circuit to be increased.

[0288] On the other hand, another transistor included in the display unit 111 functions as a switch for controlling pixel selection / non-selection and can also be called a selection transistor. The gate of the selection transistor is electrically connected to a gate line, and one of the source and drain is electrically connected to a source line (signal line). An OS transistor is preferably used as the selection transistor. This allows the gradation of a pixel to be maintained even when the frame frequency is significantly reduced (for example, 1 fps or less), thereby reducing power consumption by stopping the driver when displaying a still image.

[0289] As described above, the display device of one embodiment of the present invention can have a high aperture ratio, high definition, high display quality, and low power consumption.

[0290] A display device according to one embodiment of the present invention includes an OS transistor and a light-emitting device with a metal maskless (MML) structure. This structure significantly reduces leakage current that may flow through the transistor and leakage current that may flow between adjacent light-emitting devices (also referred to as lateral leakage current or side leakage current). Furthermore, when an image is displayed on the display device, the viewer can observe one or more of image clarity, image sharpness, high saturation, and a high contrast ratio. The extremely low leakage current that may flow through the transistor and lateral leakage current between the light-emitting devices significantly reduces light leakage during black display (so-called floating black).

[0291] In particular, among light-emitting devices with an MML structure, by applying the SBS structure described above, the layers provided between the light-emitting devices (for example, organic layers shared between the light-emitting devices, also called common layers) are configured to be separated, thereby eliminating side leakage or making it possible to greatly reduce side leakage.

[0292] 10B and 10C show other examples of the structure of a transistor that can be used as the transistor 203 and the transistor 204. In FIG.

[0293] The transistor 209 and the transistor 210 each include a conductive layer 221 functioning as a gate, an insulating layer 211 functioning as a gate insulating layer, a semiconductor layer 231 having a channel formation region 231i and a pair of low-resistance regions 231n, a conductive layer 222a connected to one of the pair of low-resistance regions 231n, a conductive layer 222b connected to the other of the pair of low-resistance regions 231n, an insulating layer 225 functioning as a gate insulating layer, a conductive layer 223 functioning as a gate, and an insulating layer 215 covering the conductive layer 223. The insulating layer 211 is located between the conductive layer 221 and the channel formation region 231i. The insulating layer 225 is located at least between the conductive layer 223 and the channel formation region 231i. Furthermore, an insulating layer 218 covering the transistor may be provided.

[0294] 10B shows an example in which the insulating layer 225 covers the top surface and side surfaces of the semiconductor layer 231. The conductive layer 222a and the conductive layer 222b are connected to the low-resistance region 231n through openings provided in the insulating layer 225 and the insulating layer 215, respectively. One of the conductive layer 222a and the conductive layer 222b functions as a source, and the other functions as a drain.

[0295] 10C , the insulating layer 225 overlaps with the channel formation region 231i of the semiconductor layer 231 but does not overlap with the low-resistance region 231n. For example, the insulating layer 225 can be processed using the conductive layer 223 as a mask to form the structure shown in FIG. 10C . In FIG. 10C , the insulating layer 215 is provided to cover the insulating layer 225 and the conductive layer 223, and the conductive layer 222a and the conductive layer 222b are each connected to the low-resistance region 231n through openings in the insulating layer 215.

[0296] A connection portion 230 is provided in a region of the substrate 110 where the substrate 140 does not overlap. In the connection portion 230, the wiring 165 is electrically connected to the FPC 118 via a conductive layer 166 and a connection layer 242. The conductive layer 166 has an example of a stacked structure including a conductive film obtained by processing the same conductive film as the conductive layers 142a and 142b, a conductive film obtained by processing the same conductive film as the conductive layers 146a and 146b, and a conductive film obtained by processing the same conductive film as the conductive layers 149a and 149b. The conductive layer 166 is exposed on the top surface of the connection portion 230. This allows the connection portion 230 and the FPC 118 to be electrically connected via the connection layer 242.

[0297] The connection layer 242 may be an anisotropic conductive film (ACF), an anisotropic conductive paste (ACP), or the like.

[0298] The connection portion 232 to which the FPC 119 is electrically connected can also have the same configuration as above.

[0299] One of the sensor electrode 130X and the sensor electrode 130Y, which functions as an electrode of the touch sensor, is provided on the solid sealing layer 150. The other of the sensor electrode 130X and the sensor electrode 130Y is provided with an insulating layer 328 interposed therebetween.

[0300] Alternatively, the sensor electrodes 130X and 130Y may be formed on the solid sealing layer 150, and an insulating layer 328 may be provided between the sensor electrodes 130X and 130Y at the intersection thereof.

[0301] The sensor electrode 130X extends in the direction in which the drive circuit 114 is provided, and is electrically connected to the connection electrode 311b through an opening provided in the solid sealing layer 150 or the like. Note that, although Fig. 10 illustrates a configuration in which the sensor electrode 130X and the connection electrode 311b are connected via the metal layer 315, the sensor electrode 130X and the connection electrode 311b may be in direct contact with each other. Note that the connection electrode 311b may have the same configuration as the pixel electrode.

[0302] An insulating layer 151 is provided on the insulating layer 328 and the other of the sensor electrode 130X and the sensor electrode 130Y. A light-shielding layer 135 is preferably provided on the insulating layer 151. The light-shielding layer 135 can be provided so as to have an area overlapping between adjacent light-emitting devices and with the drive circuits 112, 113, and 114.

[0303] The insulating layer 151 and the light-shielding layer 135 are bonded to the substrate 140 by an adhesive layer 153. In addition, various optical members such as a circular polarizer can be disposed on the outer surface of the substrate 140.

[0304] Note that the substrate 110 and the substrate 140 can be made of a material that can be used for the substrate 402 described in Embodiment 2. Alternatively, a silicon substrate on which an arithmetic circuit, a memory circuit, or the like is formed can be used. Alternatively, a glass epoxy resin substrate or the like can be used.

[0305] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0306] Embodiment 4 In this embodiment, a mode of a sensor electrode that can be applied to a display device of one embodiment of the present invention will be described.

[0307] FIG. 12A is a diagram illustrating a configuration of a display device 101 having a camera in an area overlapping with a display unit. The basic configuration of the display device 101 can be the same as that of the display device 100 described in Embodiment 1 and the like, and the display device 101 has a camera 116 on the back side of the substrate 110 (the side opposite the display unit 111). The camera 116 is a camera used primarily to photograph the user and is also called an in-camera. In FIG. 12A, the substrate 140 opposite the substrate 110 is not shown. The area where the display unit 111 and the camera 116 overlap and the vicinity thereof are referred to as area D.

[0308] Fig. 12B is a diagram showing a cross section of region D (cross section taken along D1-D2 in Fig. 12A ), and Fig. 12C is a top view of region D. Note that sensor electrode 130 is not shown in Fig. 12C .

[0309] 12C , pixel PIX1 is disposed in an area that does not overlap with camera 116, and pixel PIX2 is disposed in an area that overlaps with camera 116 or lens 116L of camera 116. Note that pixels PIX1 and PIX2 described here may also function as sub-pixels. In the following description, camera 116 can be appropriately replaced with camera lens 116L.

[0310] The pixel pitch in the region where pixel PIX2 is arranged is larger than that in the region where pixel PIX1 is arranged. In other words, the pixel density is smaller. Furthermore, pixel PIX2 has a larger pixel size than pixel PIX1. In other words, pixel PIX2 has a larger light-emitting device area than pixel PIX1.

[0311] With this configuration, the amount of light incident on the camera 116 can be increased compared to when the camera 116 is placed over the area where the pixel PIX1 is located, and more data related to imaging can be acquired. Furthermore, the portion that is lost due to the shadow of the pixel PIX2 can be compensated for by image correction that references the surrounding image. Therefore, imaging is possible even if the pixel PIX2 is placed over the camera 116.

[0312] Furthermore, although the region where pixel PIX2 is arranged has lower definition than the region where pixel PIX1 is arranged, by increasing the pixel size (area of ​​the light-emitting device), it is possible to achieve brightness equivalent to that of the region where pixel PIX1 is arranged. Furthermore, because the region where pixel PIX2 is arranged is sufficiently small compared to the entire display unit, the user can view the display without feeling it is unnatural.

[0313] In this way, the camera 116 can be arranged in an area overlapping the display unit 111, thereby enlarging the area of ​​the display unit 111. Furthermore, a pinhole or cutout, which is necessary when the display unit 111 and the camera 116 are arranged to overlap, can be eliminated.

[0314] 13A and 13B are top views of region D, showing the sensor electrode 130. For clarity, pixels PIX1 and PIX2 are not shown. Here, the sensor electrode 130 will be described without distinguishing between the conductive layers connected in the X direction and the conductive layers connected in the Y direction.

[0315] 13A is a top view of the sensor electrode 130 when a light-transmitting conductive film 131T is used as the sensor electrode 130. The light-transmitting conductive film 131T has sufficient light transmittance, so that the film 131T can be disposed so as to overlap the camera 116.

[0316] Fig. 13B is a top view of a case where a metal layer 131M is used as the sensor electrode 130. Because the metal layer 131M is basically not light-transmitting, as shown in Fig. 14A, the metal layer 131M is disposed in an area that does not overlap with the pixels PIX1 and PIX2. Note that in Fig. 14A, the portion corresponding to the outline of the sensor electrode 130 is indicated by a dashed line.

[0317] 14B, the metal layer 131M is preferably arranged to have an area overlapping with the gate line GL and the source line SL electrically connected to the pixel PIX (pixels PIX1 and PIX2) via an insulating layer (not shown). With this configuration, light emitted by the light-emitting device can be emitted to the outside without being blocked.

[0318] Here, it is preferable that the area of ​​the metal layer 131M in the region where the pixel PIX2 is arranged be smaller than that in the region where the pixel PIX1 is arranged. By adopting this configuration, it is possible to minimize the reduction in the amount of light incident on the camera 116.

[0319] 15A is a top view of a case where a translucent conductive film 131T and a metal layer 131M are used as the sensor electrode 130. As shown in Fig. 15B, the sensor electrode 130 is provided with a metal layer 131M in the region overlapping with pixel PIX1, and the sensor electrode 130 is provided with a translucent conductive film 131T in the region overlapping with pixel PIX2. Note that near the edge of the region where pixel PIX2 is provided, the translucent conductive film 131T and the metal layer 131M extending into the region overlapping with pixel PIX1 come into contact with each other, allowing electrical conduction between them.

[0320] 16A and 16B show a configuration in which the sensor electrode 130 is provided by the metal layer 131M in the region overlapping with pixel PIX1, and the sensor electrode 130 is not provided in the region overlapping with pixel PIX2. Because the diameter of the lens 116L is small compared to a fingertip, for example, a configuration in which the sensor electrode 130 is not provided on the camera 116 may not pose a problem depending on the application. This configuration minimizes obstacles that block light incident on the lens 116L, making it easier to improve imaging capabilities.

[0321] 16A and 16B, the sensor electrode 130 may be disconnected in one or both of the X and Y directions in the region where it overlaps with the camera 116. For example, if the sensor electrode 130 is disconnected in the X direction, as shown in FIG. 17A, drive circuits 114 (drive circuits 114a and 114b) may be disposed on both sides of the sensor electrode 130, and pulse voltages may be input by scanning from both sides at the same timing. In this case, since there is no disconnection in the Y direction, readout may be performed from one side for all columns.

[0322] 17B, ​​in the case where the sensor electrode 130 is broken in both the X direction and the Y direction, the drive circuits 114 (drive circuits 114a and 114b) are arranged on both sides of the sensor electrode 130, as in the case of Fig. 17A. Then, a pulse voltage is input by scanning from both sides at the same timing, and the column that is divided by the break in the Y direction of the sensor electrode 130 can be read from both sides.

[0323] In the above-described embodiment having the metal layer 131M, for example, the case where the long axis of the metal layer 131M forms an angle of 45° with the outer peripheral side of the display unit has been exemplified, but as shown in Fig. 18A, a configuration may also be used in which the metal layer 131M is parallel to the outer peripheral side of the sensor electrode 130. With this configuration, it is possible to make the reflected light of the metal layer 131M against external light less visible.

[0324] Furthermore, in the embodiment having the metal layer 131M described above, an example has been shown in which the metal layer 131M is arranged to surround one pixel PIX, but as shown in Figures 18B and 18C, the metal layer 131M may also be arranged to surround multiple pixels, such as three or six.

[0325] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0326] Embodiment Mode 5 In this embodiment mode, examples of electronic devices including the display device will be described with reference to FIGS. 19A to 19F. FIG.

[0327] Examples of electronic devices using a display device according to one embodiment of the present invention include display devices such as televisions and monitors, lighting devices, desktop or notebook personal computers, word processors, and DVD (Digital Versatile Examples of such devices include image playback devices that play back still images or videos stored on recording media such as a CD or DVD, portable CD players, radios, tape recorders, headphone stereos, stereos, table clocks, wall clocks, cordless telephone handsets, transceivers, mobile phones, car phones, portable game consoles, tablet terminals, large game machines such as pachinko machines, calculators, portable information terminals (also referred to as "mobile information terminals"), electronic organizers, e-book terminals, electronic translators, voice input devices, video cameras, digital still cameras, electric shavers, high-frequency heating devices such as microwave ovens, electric rice cookers, electric washing machines, electric vacuum cleaners, water heaters, electric fans, hair dryers, air conditioning equipment such as air conditioners, humidifiers, and dehumidifiers, dishwashers, dish dryers, clothes dryers, futon dryers, electric refrigerators, electric freezers, electric refrigerator-freezers, DNA storage freezers, flashlights, tools such as chainsaws, smoke detectors, and medical equipment such as dialysis machines. Further examples include industrial equipment such as guide lights, traffic lights, belt conveyors, elevators, escalators, industrial robots, power storage systems, and power storage devices for power leveling and smart grids.

[0328] Mobile bodies propelled by an electric motor using power from a power storage device are also included in the category of electronic devices. Examples of such mobile bodies include electric vehicles (EVs), hybrid vehicles (HVs) that combine an internal combustion engine and an electric motor, plug-in hybrid vehicles (PHVs), tracked vehicles in which the tires and wheels of these vehicles are replaced with tracks, mopeds including electrically assisted bicycles, motorcycles, electric wheelchairs, golf carts, small or large ships, submarines, helicopters, aircraft, rockets, artificial satellites, space probes, interstellar probes, and spacecraft.

[0329] A display device according to one embodiment of the present invention can be used for a display portion, a communication device, or the like built into these electronic devices.

[0330] The electronic device may have sensors (including the ability to sense, detect or measure force, displacement, position, velocity, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemicals, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, smell or infrared rays), etc.

[0331] Electronic devices can have various functions, such as a function to display various information (still images, videos, text images, etc.) on a display unit, a touch panel function, a function to display a calendar, date, time, etc., a function to execute various software (programs), a wireless communication function, and a function to read out programs or data recorded on a recording medium.

[0332] 19A to 19F show an example of an electronic device.

[0333] 19A illustrates an example of a wristwatch-type portable information terminal. The portable information terminal 6100 includes a housing 6101, a display portion 6102, a band 6103, operation buttons 6105, and the like. By using a display device according to one embodiment of the present invention for the display portion 6102, the portable information terminal 6100 can be made smaller.

[0334] 19B shows an example of a mobile phone. A mobile information terminal 6200 includes a display portion 6202 incorporated in a housing 6201, operation buttons 6203, a speaker 6204, a microphone 6205, and the like. The display portion 6202 includes a touch sensor and functions as a touch panel.

[0335] In addition, the portable information terminal 6200 includes a camera 6209 in a region overlapping with the display portion 6202. With this configuration, a pinhole or a notch formed in the display portion 6202 for arranging a camera can be unnecessary.

[0336] By using a display device according to one embodiment of the present invention for the display portion 6202, the portable information terminal 6200 can be made smaller.

[0337] 19C shows an example of a cleaning robot. The cleaning robot 6300 includes a display portion 6302 arranged on the top surface of a housing 6301, a plurality of cameras 6303 arranged on the side surface, a brush 6304, an operation button 6305, various sensors, and the like. The display portion 6302 is provided with a touch sensor and functions as a touch panel. Although not shown, the cleaning robot 6300 also includes tires, a suction port, and the like. The cleaning robot 6300 can move by itself, detect dust 6310, and suck up the dust from a suction port provided on the bottom surface.

[0338] For example, the cleaning robot 6300 can analyze an image captured by the camera 6303 to determine whether or not there is an obstacle such as a wall, furniture, or a step. When an object that may become entangled in the brush 6304, such as a wire, is detected by image analysis, the cleaning robot 6300 can stop rotation of the brush 6304. By using the display device according to one embodiment of the present invention for the display portion 6302, the cleaning robot 6300 can be miniaturized.

[0339] Fig. 19D shows an example of a robot. A robot 6400 shown in Fig. 19D includes a computing device 6409, an illuminance sensor 6401, a microphone 6402, an upper camera 6403, a speaker 6404, a display unit 6405, a lower camera 6406, an obstacle sensor 6407, and a movement mechanism 6408.

[0340] The microphone 6402 has a function of detecting the user's voice, environmental sounds, etc. The speaker 6404 has a function of emitting sound. The robot 6400 can communicate with the user using the microphone 6402 and the speaker 6404.

[0341] The display unit 6405 has a function of displaying various information. The robot 6400 can display information desired by the user on the display unit 6405. The display unit 6405 has a touch sensor and functions as a touch panel. The display unit 6405 may also be a detachable information terminal, which can be installed in a fixed position on the robot 6400 to enable charging and data transfer.

[0342] The display portion 6405 is equipped with an illuminance sensor, a camera, operation buttons, and the like, and can be touch-operated with a stylus pen, etc. Functions of the display portion 6405 include voice communication, video communication, e-mail, a notebook, Internet connection, music playback, and the like.

[0343] The upper camera 6403 and the lower camera 6406 have a function of capturing images of the periphery of the robot 6400. The obstacle sensor 6407 can detect the presence or absence of an obstacle in the moving direction when the robot 6400 moves forward using the moving mechanism 6408. The robot 6400 can recognize the surrounding environment and move safely using the upper camera 6403, the lower camera 6406, and the obstacle sensor 6407. The light-emitting device of one embodiment of the present invention can be used for the display portion 6405.

[0344] By using the display device according to one embodiment of the present invention for the display portion 6302, the robot 6400 can be miniaturized.

[0345] 19E shows an example of a television receiver. A television receiver 6500 shown in FIG. 19E includes a housing 6501, a display portion 6502, a speaker 6503, and the like.

[0346] The television receiver 6500 can be downsized by using the display device according to one embodiment of the present invention for the display portion 6502. The display portion 6502 includes a touch sensor and functions as a touch panel.

[0347] 19F illustrates an example of an automobile. The automobile 7160 includes an engine, tires, brakes, a steering device, a camera, and the like. The automobile 7160 includes a display device according to one embodiment of the present invention inside. The display device also includes a touch sensor and functions as a touch panel.

[0348] 20A shows an example of a laptop personal computer. The laptop personal computer 7200 includes a housing 7211, a keyboard 7212, a pointing device 7213, and an external connection port 7214. A display unit 7000 is incorporated in the housing 7211. The display unit 7000 includes a touch sensor and functions as a touch panel.

[0349] 20B and 20C show an example of digital signage.

[0350] 20B includes a housing 7301, a display portion 7000, and a speaker 7303. The digital signage 7300 may further include an LED lamp, operation keys (including a power switch or an operation switch), a connection terminal, various sensors, a microphone, and the like.

[0351] 20C shows a digital signage 7400 attached to a cylindrical pillar 7401. The digital signage 7400 has a display unit 7000 provided along the curved surface of the pillar 7401.

[0352] 20B and 20C, the display unit 7000 includes a touch sensor and functions as a touch panel.

[0353] 21A and 21B , an example of an electronic device including a foldable display device will be described. As shown in FIG. 21A , an electronic device 500 including a display device of one embodiment of the present invention includes a display device including regions 501A, 501B, and 501C in a housing 502. The regions 501B and 501C can be provided in a bent portion because the display device can be accommodated in the housing 502 in a folded shape.

[0354] Fig. 21B is a cross-sectional view taken along X1-X2 of electronic device 500 shown in Fig. 21A. As shown in Fig. 21B, in electronic device 500, a display device having folded substrates 110 and 140 is housed in housing 502. Housing 502 also contains substrate 540 connected to the display device. Housing 502 protects the display device and other components from external stress.

[0355] Areas 501A, 501B, and 501C corresponding to the display unit can be arranged not only on the flat portion of the housing 502 but also on the curved portion. Furthermore, areas 501A, 501B, and 501C are provided with touch sensors and function as touch panels.

[0356] 21C will be used to describe an example of an electronic device including a foldable display device different from those shown in FIGS. 21A and 21B . As shown in FIG. 21C , an electronic device 500A including a display device of one embodiment of the present invention includes a display device 501 housed in a foldable housing 502. Both the housing 502 and the display device 501 are foldable display devices, and therefore the electronic device can be a foldable electronic device.

[0357] 21C , electronic device 500A has substrate 110 and substrate 140 provided along housing 502. Display device 501 can be provided regardless of the shape of electronic device 500. By configuring the electronic device as shown in FIG. 21C , it is possible to provide a deformable configuration.

[0358] The structures, configurations, methods, and the like described in this embodiment can be used in appropriate combination with the structures, configurations, methods, and the like described in other embodiments.

[0359] AL: wiring, CL: wiring, GL: gate line, PIX: pixel, RL: wiring, SL: source line, 90B: light-emitting device, 90G: light-emitting device, 90R: light-emitting device, 100T: transistor, 100: display device, 110: substrate, 111: display unit, 112: drive circuit, 113: drive circuit, 114a: drive circuit, 114b: drive circuit, 114: drive circuit, 116L: lens, 116: camera, 118: FPC, 119: FPC, 120a: pixel, 120b: pixel, 120: pixel, 121: pixel array, 122a: sub-pixel, 122b: sub-pixel, 122c: sub-pixel , 122: subpixel, 130X: sensor electrode, 130Y: sensor electrode, 130: sensor electrode, 131M: metal layer, 131T: light-transmitting conductive film, 131X: conductive layer, 131Y: conductive layer, 132: conductive layer, 135: light-shielding layer, 140: substrate, 142a: conductive layer, 142b: conductive layer, 146a: conductive layer, 146b: conductive layer, 148: layer, 149a: conductive layer, 149b: conductive layer, 150: solid sealing layer, 151: insulating layer, 153: adhesive layer, 165: wiring, 166: conductive layer, 201: transistor, 202: transistor, 203: transistor, 204: transistor, 2 05: transistor, 209: transistor, 210: transistor, 211: insulating layer, 213: insulating layer, 214: insulating layer, 215: insulating layer, 218: insulating layer, 221: conductive layer, 222a: conductive layer, 222b: conductive layer, 223: conductive layer, 225: insulating layer, 230: connecting portion, 231i: channel formation region, 231n: low resistance region, 231: semiconductor layer, 232: connecting portion, 242: connecting layer, 301: insulating layer, 311a: connecting electrode, 311b: connecting electrode, 311B: pixel electrode, 311G: pixel electrode, 311: pixel electrode, 312B: organic layer, 312G: organic layer, 31 3: common electrode, 315: metal layer, 321: protective layer, 322: insulating layer, 325: insulating layer, 326: resin layer, 327B: protective layer, 327G: protective layer, 328: insulating layer, 330a: connecting portion, 330b: connecting portion, 340: insulating layer, 402: substrate, 404e: conductive layer, 404: conductive layer, 406: insulating layer, 407a: insulating layer, 407b: insulating layer, 407c: insulating layer, 407: insulating layer, 408: semiconductor layer, 412a: conductive layer, 412a_1: conductive layer, 412a_2: conductive layer, 412b: conductive layer, 415: conductive layer, 441: opening, 500A: electronic device, 500: electronic device,501A: area, 501B: area, 501C: area, 501: display device, 502: housing, 540: board, 6100: mobile information terminal, 6101: housing, 6102: display unit, 6103: band, 6105: operation button, 6200: mobile information terminal, 6201: housing, 6202: display unit, 6203: operation button, 6204: speaker, 6205: microphone, 6209: camera, 6300: cleaning robot, 6301: housing, 6302: display unit, 6303: camera, 6304: brush, 6305: operation button, 6310: dust, 6400: robot, 6401: illuminance sensor, 6402: microphone 6403: upper camera, 6404: speaker, 6405: display unit, 6406: lower camera, 6407: obstacle sensor, 6408: moving mechanism, 6409: computing device, 6500: television receiver, 6501: housing, 6502: display unit, 6503: speaker, 7000: display unit, 7160: automobile, 7200: notebook personal computer, 7211: housing, 7212: keyboard, 7213: pointing device, 7214: external connection port, 7300: digital signage, 7301: housing, 7303: speaker, 7400: digital signage, 7401: pillar,

Claims

1. It comprises a pixel circuit, a light-emitting device, a sensor electrode, and a first drive circuit. The first drive circuit has the function of supplying a signal potential to the sensor electrode, The pixel circuit and the first drive circuit are provided on the same substrate. The pixel circuit has a first transistor, The first drive circuit has a second transistor, The light-emitting device comprises a first electrode, a light-emitting layer, and a second electrode. The light-emitting layer is provided between the first electrode and the second electrode, The first electrode is electrically connected to either the source or the drain of the first transistor. The second electrode is electrically connected to a power line in a first region outside the display unit where the pixel circuit and the light-emitting device are located. A first insulating layer is provided on the second electrode. In a second region further away from the display unit than the first region, an opening is provided in the first insulating layer. The sensor electrode is provided on the first insulating layer. The sensor electrode is electrically connected to the source or drain of the second transistor via the opening. The second transistor is a display device having a channel-forming region along the side surface of a second insulating layer provided on the substrate.

2. In claim 1, The sensor electrode is electrically connected to the source or drain of the second transistor via a connecting electrode in the display device.

3. In claim 1, The first transistor is a display device having a channel-forming region along the side surface of the second insulating layer.

4. In claim 1, The second transistor is a display device having a metal oxide in its channel-forming region.

5. In claim 1, It has a second drive circuit, The pixel circuit has a third transistor, The second drive circuit has the function of a gate driver, The second drive circuit has a fourth transistor, Either the source or drain of the fourth transistor is electrically connected to the gate of the third transistor. The fourth transistor is a display device having a channel-forming region along the side surface of the second insulating layer.

6. In claim 5, The fourth transistor is a display device having a metal oxide in its channel-forming region.

7. In claim 1, It has a third drive circuit, The pixel circuit has a fifth transistor, The third drive circuit has the function of a source driver, The third drive circuit has a sixth transistor, Either the source or drain of the sixth transistor is electrically connected to either the source or drain of the fifth transistor. The sixth transistor is a display device having a channel-forming region along the side surface of the second insulating layer.

8. In claim 7, The sixth transistor is a display device having a metal oxide in its channel-forming region.

9. In claim 1, A camera is provided on the side of the substrate opposite to the side on which the pixel circuit is provided. In the display unit, the third region overlapping with the camera lens has a larger pixel pitch than the fourth region not overlapping with the camera lens.

10. In claim 9, A display device in which, in the third and fourth regions, the sensor electrode is provided with a metal layer such that it has an area that overlaps with the wiring electrically connected to the pixel circuit.

11. In claim 9, In the third region, the sensor electrode has a light-transmitting conductive film, In the fourth region, the sensor electrode has a region that overlaps with the wiring electrically connected to the pixel circuit, and has a metal layer. The light-transmitting conductive film extends to the fourth region and is electrically connected to the metal layer in the display device.

12. In claim 9, In the fourth region, the sensor electrode has a region that overlaps with the wiring electrically connected to the pixel circuit, and has a metal layer. A display device in which the sensor electrode is not provided in the third region.

13. An electronic device comprising a display device according to any one of claims 1 to 12, and a speaker.