Light-emitting device

Abstract

To suppress malfunctions.SOLUTION: A semiconductor device includes a field-effect transistor, a switch, and a capacitive element. The field-effect transistor has a first gate and a second gate that are superposed on each other via a channel formation region. A value of threshold voltage varies depending on potential of the second gate. The switch has a function of controlling whether or not one of a source and a drain of the field-effect transistor, and the second gate in the field-effect transistor are brought into a conduction state. The capacitive element has a function of holding voltage between the second gate in the field-effect transistor and the other of the source and the drain in the field-effect transistor.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] One aspect of the present invention relates to a semiconductor device. Another aspect of the present invention relates to a light-emitting device. Also, one aspect of the present invention relates to an electronic device.

Background Art

[0002] In recent years, the development of semiconductor devices using field-effect transistors has been advanced.

[0003] Examples of the semiconductor device include a semiconductor device that controls the amount of current flowing between the source and drain of the field-effect transistor to perform a desired operation (for example, Patent Document 1 ). )

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in conventional semiconductor devices, there has been a problem that it is difficult to control the amount of current flowing between the source and drain due to variations in the threshold voltage of the field-effect transistor. If the amount of current flowing between the source and drain cannot be controlled, malfunctions may occur in the semiconductor device, for example. One or more of suppressing malfunctions and reducing the influence of variations in the threshold voltage of the field-effect transistor are regarded as one of the problems.

[0006] One aspect of the present invention makes it one of the problems to suppress malfunctions and / or reduce the influence of variations in the threshold voltage of the field-effect transistor.

Means for Solving the Problems

[0007] In one aspect of the present invention, a field effect transistor having a first gate and a second gate that overlap each other via a channel formation region is used. Further, by controlling the potential of the second gate, the threshold voltage of the field effect transistor is set. With the above configuration, control of the amount of current flowing between the source and the drain of the field effect transistor during operation is achieved.

[0008] One aspect of the present invention is a semiconductor device including a field effect transistor, a switch, and a capacitive element.

[0009] The above field effect transistor has a first gate and a second gate that overlap each other via a channel formation region. The value of the threshold voltage in the field effect transistor changes according to the potential of the second gate. Also, the field effect transistor may be normally-on. For example, the field effect transistor may be a depletion type transistor.

[0010] The above switch has a function of controlling whether to conduct one of the source and the drain of the field effect transistor and the second gate in the field effect transistor.

[0011] The above capacitive element has a function of holding the voltage between the second gate in the field effect transistor and the other of the source and the drain in the field effect transistor.

Advantages of the Invention

[0012] According to one aspect of the present invention, operation failures are suppressed, and the threshold voltage of the field effect transistor ​​​​​​​​​​One or more effects of reducing the influence of variations can be obtained.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Embodiments for Carrying Out the Invention

[0014] Examples of embodiments according to the present invention will be described below. Note that it is easy for those skilled in the art to change the content of the embodiments without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the description content of the embodiments shown below.

[0015] Note that part or all of the content in each embodiment (for example, the content shown in the specification or drawings) can be appropriately combined with each other appropriately. Also, part of the content in each embodiment can be appropriately replaced with each other It can be switched.

[0016] Also, ordinal numbers such as the first and the second are attached to avoid confusion of components, and the number of each component is not limited to the number of ordinal numbers.

[0017] (Embodiment 1) In this embodiment, an example of a semiconductor device including a field effect transistor having two gates will be described with reference to FIG. 1.

[0018] The semiconductor device shown in FIG. 1(A) includes a field effect transistor Tr, a switch Sw, and a capacitive element Cp.

[0019] The field effect transistor Tr has a first gate and a second gate. The first gate and the second gate in the field effect transistor Tr overlap each other via a channel formation region. Also, the threshold voltage value of the field effect transistor Tr is controlled according to the potential of the second gate.

[0020] As the field effect transistor Tr, an enhancement type or a depletion type field effect transistor can be used.

[0021] The switch Sw has a function of controlling whether to conduct one of the source and the drain in the field effect transistor Tr and the second gate in the field effect transistor Tr.

[0022] The capacitive element Cp has a function of holding the voltage between the second gate in the field effect transistor Tr and the other of the source and the drain in the field effect transistor Tr.

[0023] Next, as an example of a driving method of the semiconductor device in the present embodiment, a driving method example of the semiconductor device shown in FIG. 1(A) will be described with reference to FIGS. 1(B-1) to 1(B-3). Here, as an example, a case where the field effect transistor Tr is a depletion-type N-channel transistor will be described.

[0024] In the driving method example of the semiconductor device shown in FIG. 1(A), as shown in FIG. 1(B-1), during period T1 , the switch Sw is turned on (also referred to as state ON). Also, a potential V1 is supplied to the first gate of the field effect transistor Tr. Also, a potential V2 is supplied to the second gate of the field effect transistor T r. Also, a potential Vb is supplied to the other of the source and drain of the field effect transistor Tr. Note that the value of V2 is assumed to be larger than the value of V1 - Vb.

[0025] At this time, the second gate and the drain of the field effect transistor Tr become conductive , and the potentials of the second gate and the drain of the field effect transistor Tr each become the potential V2. As a result, the threshold voltage (also referred to as Vth h) of the field effect transistor Tr shifts in the negative direction according to the potential V2.

[0026] For example, if the threshold voltage of the original field effect transistor Tr is Vth0, the threshold voltage of the field effect transistor Tr during period T1 becomes Vth0 - ΔVth. At this time, the value of ΔV th is determined according to the value of the potential V2. Therefore, the value of the threshold voltage of the field effect transistor Tr changes according to the value of the potential V2.

[0027] Also, the voltage between the first gate and the source of the field effect transistor Tr (also referred to as Vgs​​​​ becomes V1 - Vb. At this time, the value of V1 - Vb is greater than the threshold voltage of the field - effect transistor Tr in the period T1. Therefore, the field - effect transistor Tr is in the on - state

[0028] Next, in the period T2, the switch Sw is turned on. Also, a potential V1 is supplied to the first gate of the field - effect transistor Tr. Further, the second gate of the field - effect transistor Tr is made floating

[0029] At this time, the field - effect transistor Tr remains in the on - state. Thus, a current flows between the source and the drain of the field - effect transistor Tr, and the potential of the second gate of the field - effect transistor Tr changes. As a result, the value of the threshold voltage of the field - effect transistor Tr shifts in the positive direction, and when the threshold voltage of the field - effect transistor Tr becomes equal to or higher than V1 - Vb, the field - effect transistor Tr turns off. Thus, the threshold - voltage data of the field - effect transistor Tr is obtained

[0030] Next, in the period T3, the switch Sw is turned off. Also, the potential of the first gate of the field - effect transistor Tr is set to V1 + Vsig, and the first gate of the field - effect transistor Tr is made floating. Vsig is the potential of the data signal. Further, the second gate of the field - effect transistor Tr is made floating. Also, a potential Va is supplied to one of the source and the drain of the field - effect transistor

[0031] At this time, the field - effect transistor Tr turns on, and in the field - effect transistor Tr ​​​​​​​​​​​A current flows between the source and the drain. At this time, in the field effect transistor Tr Let the potential of the other source and drain be the potential Vc.

[0032] For example, when the field effect transistor Tr operates in the saturation region, the value of the current (Ids) flowing between the source and the drain in the field effect transistor Tr is determined according to the value of the data signal input to the first gate, regardless of the threshold voltage of the field effect transistor Tr. Therefore, for example, when Vgs is greater than V1 - Vb, the field effect transistor Tr is turned on and a current flows between the source and the drain.

[0033] Also, even when the potential of the other source and drain of the field effect transistor Tr changes due to deterioration of the field effect transistor Tr or the like, the first gate and the second gate in the field effect transistor Tr are in a floating state, and because there is the capacitor element Cp, the change in the voltage between the first gate and the source in the field effect transistor Tr can be suppressed.

[0034] Note that a mobility correction period may be provided between the period T2 and the period T3, and the potential of the second gate in the field effect transistor Tr may be set according to the mobility of the field effect transistor Tr. Thereby, the influence due to the variation in the mobility of the field effect transistor Tr can be suppressed.

[0035] The above is the description of an example of the driving method of the semiconductor device in the present embodiment.

[0036] As described with reference to FIG. 1, in an example of the semiconductor device in the present embodiment, a threshold voltage data acquisition period (for example, the period T2) is provided, and the data of the threshold voltage of the field effect transistor is obtained in advance Obtain this. As a result, the current flowing between the source and drain of the field-effect transistor amount can be determined regardless of the threshold voltage of the field-effect transistor, so the influence due to variations in the threshold voltage of the field-effect transistor can be suppressed. Also, the influence due to deterioration of the field-effect transistor can be suppressed.

[0037] Further, in an example of the semiconductor device in this embodiment, a field-effect transistor having a first gate and a second gate that overlap each other via a channel formation region is used. With the above configuration, even if the field-effect transistor is a depletion-type transistor, the threshold voltage data of the field-effect transistor can be obtained. Because the threshold voltage of the field-effect transistor can be shifted by the potential of the second gate, even if the field-effect transistor is an N-channel transistor and the original threshold voltage of the field-effect transistor is a negative value and non-monotonic, and even if the voltage between the first gate and the source in the field-effect transistor does not become a negative value, the field-effect transistor can be turned off. Therefore, the amount of current flowing between the source and drain in the field-effect transistor can be determined regardless of the threshold voltage of the field-effect transistor, so the influence due to variations in the threshold voltage of the field-effect transistor can be suppressed.

[0038] Therefore, in an example of the semiconductor device in this embodiment, since the amount of current flowing between the source and drain in the field-effect transistor can be controlled, malfunction can be suppressed.

[0039] (Embodiment 2) In this embodiment, an example of a light-emitting device including a field-effect transistor having two gates will be described. Hereinafter, a description will be given with reference to FIGS. 2 to 6.

[0040] The light-emitting device shown in FIG. 2(A) includes wirings 151 to 158, field-effect transistors 11 1 to 118, capacitor elements 121 and 122, and a light-emitting element (also referred to as EL) 140.

[0041] The wiring 151 functions as, for example, a data signal line for supplying a data signal.

[0042] The wiring 152 functions as, for example, a potential supply line for supplying a potential.

[0043] The wiring 153 functions as, for example, a gate signal line for supplying a gate signal that is a pulse signal and has such a function.

[0044] The wiring 154 functions as, for example, a gate signal line for supplying a gate signal that is a pulse signal and has such a function.

[0045] The wiring 155 functions as, for example, a gate signal line for supplying a gate signal that is a pulse signal and has such a function.

[0046] The wiring 156 functions as, for example, a potential supply line for supplying a potential.

[0047] The wiring 157 functions as, for example, a potential supply line for supplying a potential.

[0048] The wiring 158 functions as, for example, a potential supply line for supplying a potential.

[0049] One of the source and drain of the field-effect transistor 111 is electrically connected to the wiring 151. Further, the gate of the field-effect transistor 111 is electrically connected to the wiring 153 is connected thereto.

[0050] One of the source and drain in the field effect transistor 112 is electrically connected to the other of the source and drain in the field effect transistor 111. Also, the gate in the field effect transistor 112 is electrically connected to the wiring 154.

[0051] One of the pair of electrodes in the capacitive element 121 is electrically connected to the other of the source and drain in the field effect transistor 111.

[0052] The field effect transistor 113 has a first gate and a second gate that overlap each other via a channel formation region. The first gate in the field effect transistor 113 is electrically connected to the other of the source and drain in the field effect transistor 112.

[0053] One of the source and drain in the field effect transistor 114 is electrically connected to one of the source and drain in the field effect transistor 113. Also, the other of the source and drain in the field effect transistor 114 is electrically connected to the second gate in the field effect transistor 113. Also, the gate in the field effect transistor 114 is electrically connected to the wiring 153.

[0054] One of the pair of electrodes in the capacitive element 122 is electrically connected to the second gate in the field effect transistor 113. Also, the other of the pair of electrodes in the capacitive element 122 is electrically connected to the other of the source and drain in the field effect transistor 113.

[0055] One of the source and drain in the field effect transistor 115 is electrically connected to the wiring 152. The other of the source and drain in the field effect transistor 115 is electrically connected to one of the source and drain in the field effect transistor 113. The gate in the field effect transistor 115 is electrically connected to the wiring 154. It is.

[0056] One of the source and drain in the field effect transistor 116 is electrically connected to the wiring 156. The other of the source and drain in the field effect transistor 116 is electrically connected to the first gate in the field effect transistor 113. Also, the electric The gate in the field effect transistor 116 is electrically connected to the wiring 153.

[0057] One of the source and drain in the field effect transistor 117 is electrically connected to the wiring 157. The other of the source and drain in the field effect transistor 117 is electrically connected to the other of the pair of electrodes in the capacitor element 121 and the other of the pair of electrodes in the capacitor element 122. The gate in the field effect transistor 117 is electrically connected to the wiring 1 53.

[0058] One of the source and drain in the field effect transistor 118 is electrically connected to the wiring 158. The other of the source and drain in the field effect transistor 118 is electrically connected to the second gate in the field effect transistor 113. Also, the electric The gate in the field effect transistor 118 is electrically connected to the wiring 155.

[0059] One of the anode and the cathode in the light-emitting element 140 is electrically connected to the other of the source and the drain in the field-effect transistor 113. As the light-emitting element 140, for example, an electroluminescence element (also referred to as an EL element) can be used. Furthermore, the light-emitting device shown in FIG. 2(B) has a configuration in which the connection relationship between the field-effect transistors 113 and 117 in the light-emitting device shown in FIG. 2(A) is different.

[0060] In the light-emitting device shown in FIG. 2(B), the other of the source and the drain in the field-effect transistor 113 is electrically connected to the other of the source and the drain in the field-effect transistor 112. In addition, the first gate in the field-effect transistor 113 is electrically connected to the other of the pair of electrodes in the capacitor element 121.

[0061] In the light-emitting device shown in FIG. 2(B), the other of the source and the drain in the field-effect transistor 113 is electrically connected to the other of the source and the drain in the field-effect transistor 112. In addition, the other of the source and the drain in the field-effect transistor 117 is electrically connected to the other of the source and the drain in the field-effect transistor 112, and the other of the pair of electrodes in the capacitor element 122. In addition, the first gate in the field-effect transistor 113 is electrically connected to the other of the pair of electrodes in the capacitor element 121. In addition, the other of the source and the drain in the field-effect transistor 117 is electrically connected to the other of the source and the drain in the field-effect transistor 112, and the other of the pair of electrodes in the capacitor element 122. In the light-emitting device shown in FIG. 2(C), the connection relationship of the field-effect transistor 116 is different from that of the light-emitting device shown in FIG. 2(B), and there is no wiring 156. In the light-emitting device shown in FIG. 2(C), one of the source and the drain in the field-effect transistor 116 is electrically connected to the first gate in the field-effect transistor 113. In addition, the other of the source and the drain in the field-effect transistor 116 is electrically connected to the other of the pair of electrodes in the capacitor element 122.

[0062] In the light-emitting device shown in FIG. 2(C), the connection relationship of the field-effect transistor 116 is different from that of the light-emitting device shown in FIG. 2(B), and there is no wiring 156. In the light-emitting device shown in FIG. 2(C), one of the source and the drain in the field-effect transistor 116 is electrically connected to the first gate in the field-effect transistor 113.

[0063] In the light-emitting device shown in FIG. 2(C), one of the source and the drain in the field-effect transistor 116 is electrically connected to the first gate in the field-effect transistor 113. In addition, the other of the source and the drain in the field-effect transistor 116 is electrically connected to the other of the pair of electrodes in the capacitor element 122. In addition, the other of the source and the drain in the field-effect transistor 116 is electrically connected to the other of the pair of electrodes in the capacitor element 122. In addition, the other of the source and the drain in the field-effect transistor 116 is electrically connected to the other of the pair of electrodes in the capacitor element 122. 13 may be an enhancement-type transistor.

[0064] By adopting the configuration shown in FIG. 2(C), the number of wirings can be reduced.

[0065] In addition, the light-emitting device shown in FIG. 3(A) includes wirings 159 and 160 in addition to the light-emitting device shown in FIG. 2(A), and has a different connection relationship between the field-effect transistors 111 and 117 and is configured without the field-effect transistor 112.

[0066] In the light-emitting device shown in FIG. 3(A), the gate of the field-effect transistor 111 is electrically connected to the wiring 159. Also, the first gate of the field-effect transistor 113 is electrically connected to the other of the source and drain of the field-effect transistor 111. Also, the gate of the field-effect transistor 117 is electrically connected to the wiring 160.

[0067] The light-emitting device shown in FIG. 3(B) has a different connection relationship of the capacitive element 121 from that of the light-emitting device shown in FIG. 3(A).

[0068] In the light-emitting device shown in FIG. 3(B), the other of the pair of electrodes of the capacitive element 121 is electrically connected to the other of the source and drain of the field-effect transistor 111.

[0069] The light-emitting device shown in FIG. 3(C) has a different connection relationship of the field-effect transistor 116 from that of the light-emitting device shown in FIG. 3(B) and is configured without the wiring 156.

[0070] In the light-emitting device shown in FIG. 3(C), the source and drain of the field-effect transistor 116 One side of the rain is electrically connected to the first gate in the field effect transistor 113 . Also, the other of the source and drain in the field effect transistor 116 is electrically connected to the other of the pair of electrodes in the capacitor element 122. The field effect transistor 113 may be an enhancement type transistor.

[0071] By adopting the configuration shown in FIG. 3(C), the number of wirings can be reduced.

[0072] Also, by adopting the configurations shown in FIGS. 3(A) to 3(C), the number of field effect transistors can be reduced.

[0073] An example of a light emitting device including a capacitor element for adjusting the voltage applied to the light emitting element 140 will be described with reference to FIG. 4. using FIG. 4.

[0074] The light emitting device shown in FIG. 4(A) includes a capacitor element 123 in addition to the configuration of the light emitting device shown in FIG. 2(A). is provided.

[0075] In the light emitting device shown in FIG. 4(A), one of the pair of electrodes in the capacitor element 123 is electrically connected to one of the anode and cathode in the light emitting element 140. Also, a reference potential is applied to one of the pair of electrodes in the capacitor element 123. 123.

[0076] Also, the light emitting device shown in FIG. 4(B) has a configuration including a capacitor element 123 in addition to the configuration of the light emitting device shown in FIG. 2(B). The connection relationship of the capacitor element 123 is the same as that of the light emitting device shown in FIG. 4(A). is the same as that of the light emitting device shown in FIG. 4(A). same.

[0077] Also, the light emitting device shown in FIG. 4(C) has a configuration including a capacitor element 123 in addition to the configuration of the light emitting device shown in FIG. 2(C). The connection of the capacitor 123 is the same as that of the light-emitting device shown in FIG. It's the same.

[0078] Note that the light emitting device is not limited to the light emitting device shown in FIG. 4(A) to FIG. 4(C). For example, the light emitting device shown in FIG. A capacitive element may be provided in addition to the configuration of the light emitting device shown in FIG.

[0079] Next, an example of a method for driving the light emitting device according to this embodiment will be described with reference to FIGS. .

[0080] As an example of a method for driving the light emitting device in this embodiment, a method for driving the light emitting device shown in FIG. An example will be described with reference to the timing chart of FIG. The device is a light-emitting device shown in FIG. 2A, in which the light-emitting element 140 is a light-emitting diode, and Each of the transistors 111 to 118 is an N-channel transistor. In this case, the light emitting device is a light emitting diode which is a light emitting element 140. The anode in the capacitor 122 is electrically connected to the other of the pair of electrodes in the capacitor 122. A potential Vx is applied to the cathode of the light-emitting diode which is the light-emitting element 140.

[0081] In the example of the method for driving the light emitting device shown in FIG. 5A, as shown in FIG. 5B, in the period T11, A high-level (VH) signal is input via the wiring 153, and a low-level (VL) signal is input via the wiring 154. and a high-level signal is input via wiring 155. A potential V11 is supplied to the wiring 156, and a potential V12 is supplied to the wiring 157. A potential V13 is supplied to the wiring 158. At this time, the potential difference between the potentials V11 and V12 is Assume that it is greater than the threshold voltage (also referred to as Vth113) of the field effect transistor 113. Also, assume that the potential V12 is smaller than the potential Vx.

[0082] At this time, the field effect transistors 111, 114, 116, 117, and 118 turn on, and the field effect transistors 112 and 115 turn off.

[0083] Also, the second gate and the drain of the field effect transistor 113 become conductive, and the potentials of the second gate and the drain of the field effect transistor 113 each become the potential V13. As a result, the threshold voltage of the field effect transistor 113 shifts in the negative direction according to the potential V13.

[0084] Also, the voltage (also referred to as Vgs113) between the first gate and the source of the field effect transistor 113 becomes V11 - V12. The value of V11 - V12 is greater than the threshold voltage of the field effect transistor 113 at this time. Therefore, the field effect transistor 113 turns on.

[0085] Next, in the period T12, a data signal is input via the wiring 151, a high-level signal is input via the wiring 153, a low-level signal is input via the wiring 154, and a low-level signal is input via the wiring 155. Also, the potential V11 is supplied to the wiring 156, and the potential V12 is supplied to the wiring 157.

[0086] At this time, the field effect transistors 111, 114, 116, 117, and 118 The dissta 116 and the field effect transistor 117 turn on, and the field effect transistors 112, 115, and 118 turn off.

[0087] Also, the field effect transistor 113 remains on. Therefore, when a current flows between the source and the drain in the field effect transistor 113, the potential of the second gate in the field effect transistor 113 changes. As a result, the value of the threshold voltage in the field effect transistor 113 shifts in the positive direction, and when the threshold voltage in the field effect transistor 113 becomes equal to or higher than V11 - V12, the field effect transistor 113 turns off. Thereby, the threshold voltage data of the field effect transistor 113 is obtained.

[0088] Also, the potential of one of the pair of electrodes in the capacitive element 121 becomes the potential (Vsig) of the data signal input via the wiring 151.

[0089] Next, in the period T13, a low-level signal is input via the wiring 153, a high-level signal is input via the wiring 154, and a low-level signal is input via the wiring 155. Also, the potential Vdd is supplied to the wiring 152. Note that the value of the potential Vdd is set to be higher than the potential V11. Also, although a high-level signal is input via the wiring 154 after a low-level signal is input via the wiring 153 in the period T13, it is not limited thereto.

[0090] At this time, the field effect transistors 112 and 115 turn on, and the field effect transistors 111, 114, and ​​​​​​116, the field effect transistor 117, and the field effect transistor 118 are turned off. become.

[0091] Furthermore, the potential of the first gate in the field effect transistor 113 changes according to the value of the data signal. As a result, the field effect transistor 113 turns on, and a current flows between the source and the drain in the field effect transistor 113. flows.

[0092] Furthermore, a current flows between the anode and the cathode in the light emitting diode which is the light emitting element 140, and the light emitting diode which is the light emitting element 140 emits light. flows, and the light emitting diode which is the light emitting element 140 emits light.

[0093] For example, when the field effect transistor 113 operates in the saturation region, the current value (Ids) flowing between the source and the drain in the field effect transistor 113 is determined according to the value of the data signal input to the first gate regardless of the threshold voltage of the field effect transistor 113. source and drain in the transistor 113 independent of the threshold voltage of the transistor 113, and is determined according to the value of the data signal input to the first gate. Therefore, for example, when Vgs113 is greater than V11 - V12, the field effect transistor 113 turns on, and a current flows between the source and the drain. flows.

[0094] Also, even if the potential of the other side of the source and the drain of the field effect transistor 113 changes due to deterioration of the field effect transistor 113 or the like, the first gate and the second gate in the field effect transistor 113 are in a floating state, and since there are the capacitor element 121 and the capacitor element 122, the change in the value of the voltage between the first gate and the source in the field effect transistor 113 can be suppressed. change, the first gate and the second gate in the field effect transistor 113 are in a floating state, and due to the presence of the capacitor element 121 and the capacitor element 122, the change in the value of the voltage between the first gate and the source in the field effect transistor 113 can be suppressed. between the first gate and the source in the field effect transistor 113 can be suppressed.

[0095] Note that a mobility correction period is provided between the period T12 and the period T13, and the field effect transistor 11 Set the potential of the second gate in the field-effect transistor 113 according to the mobility of 3 This is also possible. Thereby, the influence due to the variation in the mobility of the field-effect transistor 113 is suppressed to be possible.

[0096] The above is the description of an example of the driving method of the light-emitting device shown in Fig. 5(A).

[0097] Note that one or more of the field-effect transistors 111 to 118 of the semiconductor device shown in Fig. 5(A) may be P-channel type transistors.

[0098] Next, as an example of the driving method of the light-emitting device in the present embodiment, an example of the driving method of the light-emitting device shown in Fig. 6(A) will be described using the timing chart of Fig. 6(B). The light-emitting device shown in Fig. 6(A) is a light-emitting device in which the light-emitting element 140 of the light-emitting device shown in Fig. 3(A) is a light-emitting diode, and each of the field-effect transistors 111 to 118 is an N-channel type transistor. At this time, the anode of the light-emitting diode that is the light-emitting element 140 is electrically connected to the other of the pair of electrodes in the capacitive element 122 . Further, a potential Vx is applied to the cathode of the light-emitting diode that is the light-emitting element 140 .

[0099] In the example of the driving method of the light-emitting device shown in Fig. 6(A), as shown in Fig. 6(B), during the period T21 , a high-level signal is input via the wiring 153, a low-level signal is input via the wiring 154, a high-level signal is input via the wiring 155, a low-level signal is input via the wiring 159, and a high-level signal is input via the wiring 160. Further, the wiring 1 ​​​​​​Supply potential V11 to 56, supply potential V12 to wiring 157, and supply potential V13 to wiring 158 At this time, assume that the potential difference between potential V11 and potential V12 is greater than the threshold voltage of field effect transistor 11 3. Also, assume that potential V12 is less than potential Vx.

[0100] At this time, field effect transistors 114, 116, 117, and 118 turn on, and field effect transistors 111 and 115 turn off.

[0101] Also, the second gate and drain in field effect transistor 113 become conductive, and the potentials of the second gate and drain in field effect transistor 113 each become potential V13. As a result, the threshold voltage of field effect transistor 113 shifts in the negative direction according to potential V13.

[0102] Also, the voltage between the gate and source in field effect transistor 113 becomes V11 - V12 . The value of V11 - V12 is greater than the threshold voltage of field effect transistor 113 at this time. Therefore, field effect transistor 113 turns on.

[0103] Also, in period T22, input a high-level signal via wiring 153, input a low-level signal via wiring 154 , input a low-level signal via wiring 155, input a low-level signal via wiring 159 , input a high-level signal via wiring 160. Also, supply potential V11 to wiring 156 and supply potential V12 to wiring 157.

[0104] ​​​​​At this time, the field-effect transistor 114, the field-effect transistor 116, and the field-effect transistor 117 turn on, and the field-effect transistor 111, the field-effect transistor 115, and the field-effect transistor 118 turn off.

[0105] Also, the field-effect transistor 113 remains on. Therefore, when a current flows between the source and the drain in the field-effect transistor 113, the potential of the second gate in the field-effect transistor 113 changes. As a result, the value of the threshold voltage in the field-effect transistor 113 shifts in the positive direction, and when the threshold voltage in the field-effect transistor 113 becomes equal to or higher than V11 - V12, the field-effect transistor 113 turns off. Thereby, the threshold voltage data of the field-effect transistor 113 is obtained.

[0106] Next, in the period T23, a low-level signal is input via the wiring 153, a low-level signal is input via the wiring 154, a low-level signal is input via the wiring 155, a high-level signal is input via the wiring 159, and a low-level signal is input via the wiring 160. Also, a data signal is input via the wiring 151.

[0107]

[0108] At this time, the field-effect transistor 111 turns on, and the field-effect transistor 114, the field-effect transistor 115, the field-effect transistor 116, the field-effect transistor 1 17, and the field-effect transistor 118 turn off.

[0108] At this time, the potential of the first gate in the field-effect transistor 113 changes according to the potential of the data signal (Vs ig).

[0109] Next, in period T24, a low-level signal is input via wiring 153, and a high-level signal is input via wiring 154 and a low-level signal is input via wiring 155, and a low-level signal is input via wiring 159 and a low-level signal is input via wiring 160. Also, a potential Vdd is supplied via wiring 152. Note that the value of the potential Vdd is higher than the potential V11.

[0110] At this time, the field-effect transistor 115 turns on, and the field-effect transistors 111 , 114, 116, 117, and 118 turn off.

[0111] Also, the field-effect transistor 113 turns on, and a current flows between the source and the drain in the field-effect transistor 113.

[0112] Furthermore, a current flows between the anode and the cathode in the light-emitting diode which is the light-emitting element 140, causing the light-emitting diode which is the light-emitting element 140 to emit light.

[0113] For example, when the field-effect transistor 113 operates in the saturation region, the current value (Ids) flowing between the source and the drain in the field-effect transistor 113 is determined according to the value of the data signal (Vsig) input to the first gate, regardless of the threshold voltage of the field-effect transistor 113. Thus, for example, when Vgs113 is greater than V11 - V12, the field-effect transistor 113 turns on, and a current flows between the source and the drain.

[0114] ​​​​​​​​​Also, even when the potential of the other of the source and drain in the field-effect transistor 113 changes due to deterioration of the field-effect transistor 113 or the like, the first gate and the second gate in the field-effect transistor 113 are in a floating state, and there are the capacitor elements 121 and 122. Therefore, a change in the value of the voltage between the first gate and the source in the field-effect transistor 113 can be suppressed. Since the first gate and the second gate in the field-effect transistor 113 are in a floating state and there are the capacitor elements 121 and 122, a change in the value of the voltage between the first gate and the source in the field-effect transistor 113 can be suppressed.

[0115] Note that a mobility correction period may be provided between the period T23 and the period T24, and the potential of the second gate in the field-effect transistor 113 may be set according to the mobility of the field-effect transistor 113. Thereby, the influence due to the variation in the mobility of the field-effect transistor 113 can be suppressed.

[0116] Note that one or more of the field-effect transistors 111 to 118 of the semiconductor device shown in FIG. 6(A) may be P-channel type transistors.

[0117] The above is the description of an example of the driving method of the light-emitting device shown in FIG. 6(A).

[0118] As described with reference to FIGS. 5 and 6, in an example of the light-emitting device according to the present embodiment, a threshold voltage data acquisition period is provided to acquire in advance data on the threshold voltage of the field-effect transistor. Thereby, since the amount of current flowing between the source and the drain of the field-effect transistor can be determined regardless of the threshold voltage of the field-effect transistor, the influence due to the variation in the threshold voltage of the field-effect transistor can be suppressed. Also, the influence due to the deterioration of the field-effect transistor can be suppressed.

[0119] ​​​​​​​​​​​​Also, in an example of the light-emitting device according to the present embodiment, it has a first gate and a second gate. A field-effect transistor is used. With the above configuration, even if the field-effect transistor is a depletion-type transistor, threshold voltage data of the field-effect transistor can be obtained. That is, since the threshold voltage of the field-effect transistor can be shifted by the potential of the second gate, the field-effect transistor is an N-channel type transistor, the original threshold voltage of the field-effect transistor is a negative value and is normally on, and even if the voltage between the first gate and the source in the field-effect transistor does not become a negative value, the field-effect transistor can be turned off. Therefore, since the amount of current flowing between the source and the drain in the field-effect transistor can be determined regardless of the threshold voltage of the field-effect transistor, the influence due to variations in the threshold voltage of the field-effect transistor can be suppressed. Therefore, in an example of the light-emitting device according to the present embodiment, since the amount of current flowing between the source and the drain in the field-effect transistor can be controlled, malfunction can be suppressed.

[0120] Therefore, in an example of the light-emitting device according to the present embodiment, since the amount of current flowing between the source and the drain in the field-effect transistor can be controlled, malfunction can be suppressed.

[0121] (Embodiment 3) In the present embodiment, a configuration example of a light-emitting device including a drive circuit will be described with reference to FIG. 7.

[0122] The semiconductor device shown in FIG. 7 includes a first drive circuit 901, a second drive circuit 902, and a plurality of light-emitting circuits 910.

[0123] The first drive circuit 901 has a function of controlling the light-emitting operation of the light-emitting circuit 910.

[0124] The first drive circuit 901 is configured using, for example, a shift register or the like.​​​​​​​

[0125] The second drive circuit 902 has a function of controlling the light emission operation of the light emission circuit 910.

[0126] The second drive circuit 902 is configured using, for example, a shift register, an analog switch, or the like. and the like.

[0127] A plurality of light emission circuits 910 are arranged in a matrix direction in the light emission unit 900. As the light emission circuit 910, the configuration of the light emitting device shown in the second embodiment can be applied. At this time, a signal is supplied from the first drive circuit 901 to the wiring electrically connected to the gate of the field effect transistor in the light emitting device shown in the second embodiment. Further, a data signal is supplied from the second drive circuit 902 to the wiring to which the data signal is input in the light emitting device shown in the second embodiment. and the like. and the like. and the like. and the like. and the like.

[0128] Note that the first drive circuit 901 may be provided on the same substrate as the light emission circuit 910.

[0129] The above is the description of the configuration example of the light emitting device shown in FIG. 7.

[0130] As described with reference to FIG. 7, in an example of the light emitting device according to the present embodiment, the light emission operation of the light emission circuit can be controlled by the first drive circuit and the second drive circuit. and the like.

[0131] (Embodiment 4) In this embodiment, an example of the field effect transistor in the semiconductor device or the light emitting device of the above embodiment will be described. and the like.

[0132] A structural example of the field effect transistor in this embodiment will be described with reference to FIG. 8.

[0133] The field-effect transistor shown in FIG. 8(A) has, on the device formation layer 400_A, a conductive layer 40 1_A, an insulating layer 402_A, a semiconductor layer 403_A, a conductive layer 405a_A, and a conductive layer 405b_A, and an insulating layer 406.

[0134] Also, the field-effect transistor shown in FIG. 8(B) has, on the device formation layer 400_B, a conductive layer 401_B, an insulating layer 402_B, a semiconductor layer 403_B including regions 404a and 404b, a conductive layer 405a_B, a conductive layer 405b_B, and an insulating layer 407.

[0135] Furthermore, each component shown in FIGS. 8(A) and 8(B) will be described.

[0136] As the device formation layer 400_A and the device formation layer 400_B, for example, an insulating layer or a substrate having an insulating surface can be used.

[0137] Each of the conductive layer 401_A and the conductive layer 401_B functions as the gate of the field-effect transistor. Note that a layer having the function of the gate of the field-effect transistor is also referred to as a gate electrode or a gate wiring.

[0138] As the conductive layer 401_A and the conductive layer 401_B, for example, a metal material such as molybdenum, magnesium, titanium, chromium, tantalum, tungsten, aluminum, copper, neodymium, or scandium, or a layer (single layer or laminate) of an alloy material having these as main components can be used.

[0139] Each of the insulating layer 402_A and the insulating layer 402_B functions as the gate insulating layer of the field-effect transistor.

[0140] ​​​​​​ As the insulating layers 402_A and 402_B, for example, silicon oxide, silicon nitride, silicon oxynitride, silicon nitride oxide, aluminum oxide, aluminum nitride, aluminum oxynitride, aluminum nitride oxide, hafnium oxide, or lanthanum oxide and other layers (single layer or laminated) can be used.

[0141] In addition, as the insulating layers 402_A and 402_B, for example, an insulating layer made of a material containing Group 13 elements and oxygen elements in the periodic

[0142] table can also be used. Examples of the material containing Group 13 elements and oxygen elements include gallium oxide, aluminum oxide, aluminum gallium oxide, gallium aluminum oxide, and the like. Note that aluminum gallium oxide refers to a substance in which the content (atomic %) of aluminum is

[0143] more than the content (atomic %) of gallium, and gallium aluminum oxide refers to a substance in which the content (atomic %) of gallium is more than the content (atomic %) of aluminum. Each of the semiconductor layers 403_A and 403_B functions as a layer in which a channel of a field effect transistor is formed (also referred to as a channel forming layer), that is, a layer having a channel forming region.

[0144] In addition, as the semiconductor applicable to the semiconductor layer 403_A and the semiconductor layer 403_B, for example, a semiconductor having a wider band gap than silicon, for example, 2 eV or more, preferably 2.5 eV or more, more preferably 3 eV or more can be used. For example, as the semiconductor applicable to the semiconductor layer 403_ A and the semiconductor layer 403_B, In-based oxides (such as indium oxide), Sn-based oxides (such as tin oxide), or Zn-based oxides (such as zinc oxide) and other oxide semiconductors such as metal oxides can be used.

[0145] In addition, as the above metal oxide, for example, metal oxides such as quaternary metal oxides, ternary metal oxides, and binary metal oxides can also be used. Note that the metal oxide applicable as the above oxide semiconductor may contain gallium as a stabilizer to reduce the variation in characteristics. Further, the metal oxide applicable as the above oxide semiconductor may contain tin as the above stabilizer. Further, the metal oxide applicable as the above oxide semiconductor may contain hafnium as the above stabilizer. Further, the metal oxide applicable as the above oxide semiconductor may contain aluminum as the above stabilizer. Further, the metal oxide applicable as the above oxide semiconductor may contain, as the above stabilizer, one or more of lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium, which are lanthanoids. Further, the metal oxide applicable as the above oxide semiconductor may contain silicon oxide.

[0146] For example, as the quaternary metal oxide, for example, In-Sn-Ga-Zn oxide, In-H f-Ga-Zn oxide, In-Al-Ga-Zn oxide, In-Sn-Al-Zn oxide, In-Sn-Hf-Zn oxide, In-Hf-Al-Zn oxide, etc. can be used .

[0147] In addition, as the ternary metal oxide, for example, In-Ga-Zn oxide, In-Sn-Zn oxide, In-Al-Zn oxide, Sn-Ga-Zn oxide, Al-Ga-Zn oxide, Sn-Al-Zn oxide, or In-Hf-Zn oxide, In-La-Zn oxide, In-Ce-Zn oxide, In-Pr-Zn oxide, In-Nd-Zn oxide, In-Sm-Zn oxide, In-Eu-Zn oxide, In-Gd-Zn oxide, In-Tb-Zn oxide, In-Dy-Zn oxide, In-Ho-Zn oxide, In-Er-Zn oxide, In-Tm-Zn oxide, In-Yb-Zn oxide , or In-Lu-Zn oxide, etc. can be used

[0148] In addition, as the binary metal oxide, for example, In-Zn oxide, Sn-Zn oxide, A l-Zn oxide, Zn-Mg oxide, Sn-Mg oxide, In-Mg oxide, I n-Sn oxide, or In-Ga oxide, etc. can be used

[0149] In addition, as the oxide semiconductor, a material represented by InLO3(ZnO) m (m is a number greater than 0) can also be used. InLO3(ZnO) The L in represents one or more metal elements selected from Ga, Al, Mn, and m Co .

[0150] For example, as the oxide semiconductor, In:Ga:Zn = 1:1:1 (= 1 / 3:1 / 3:1 / 3) or In:Ga:Zn = 2:2:1 (= 2 / 5:2 / 5:1 / 5) atomic ratio of In -Ga-Zn-based oxides and oxides in the vicinity of its composition can be used. Also, as the oxide semi conductor, In:Sn:Zn = 1:1:1 (= 1 / 3:1 / 3:1 / 3), In:S n:Zn = 2:1:3 (= 1 / 3:1 / 6:1 / 2) or In:Sn:Zn = 2:1:5 (= 1 / 4:1 / 8:5 / 8) atomic ratio of In-Sn-Zn-based oxides and oxides in the vicinity of its composition can be used. For example, it is preferable to form the semiconductor layer using a sputtering target having a composition such that the composition of the formed semiconductor layer becomes the above composition.

[0151] Also, when an oxide semiconductor is used for the semiconductor layer 403_A and the semiconductor layer 403_B, the semiconductor layer may be in a single crystal, polycrystalline (also referred to as polycrystal), or amorphous state.

[0152] Also, as the semiconductor layer 403_A and the semiconductor layer 403_B, an oxide semiconductor layer containing CAAC-OS (C Ax is Aligned Crystalline Oxide Semiconduct or) may be used.

[0153] CAAC-OS is a mixed-phase structure of a crystal region and an amorphous region, and in the crystal of the crystal region, the c-axis is perpendicular to the formation surface or the surface of the semiconductor layer, and when viewed from a direction perpendicular to the ab-plane, it has a triangular or hexagonal atomic arrangement, and when viewed from a direction perpendicular to the c-axis, it means a structure in which metal atoms are arranged in layers or metal atoms and oxygen atoms are arranged in layers. Therefore, CAAC-OS is a complete It is not a perfect single crystal nor a complete amorphous material. When CAAC-OS has a plurality of crystal regions, the crystals in the plurality of crystal regions may have different orientations of the a-axis and the b-axis.

[0154] Also, the size of the crystals in the crystal regions in CAAC-OS is on the order of several nm to several tens of nm when accumulated. However, in the observation of CAAC-OS by a transmission electron microscope (also referred to as TEM), the boundary between the crystal regions and the amorphous regions in CAAC-OS is not always clear. Also, in CAAC-OS, grain boundaries are not confirmed. Therefore, since CAAC-OS includes regions without grain boundaries, the decrease in electron mobility due to grain boundaries is small.

[0155] Also, in CAAC-OS, the distribution of the crystal regions may not be uniform. For example, when an oxide semiconductor layer containing CAAC-OS is formed by crystal growth from the surface side of the oxide semiconductor layer, in the vicinity of the surface of the oxide semiconductor layer in the CAAC-OS portion, the proportion of the crystal regions is high, and in the vicinity of the formed surface of the oxide semiconductor layer in the CAAC-OS portion, the proportion of the amorphous regions may be high.

[0156] Also, since the c-axis of the crystals in the crystal regions of CAAC-OS is perpendicular to the formed surface or the surface of the oxide semiconductor layer in the CAAC-OS portion, the direction of the c-axis may be different depending on the shape of the oxide semiconductor layer in the CAAC-OS portion (the cross-sectional shape of the formed surface or the cross-sectional shape of the surface). Note that the c-axis in the crystal regions of CAAC-OS is substantially perpendicular to the formed surface or the surface of the oxide semiconductor layer in the CAAC-OS portion.

[0157] Also, in CAAC-OS, a part of the oxygen may be substituted with nitrogen.

[0158] Also, CAAC-OS has a composition in the crystal region of In 1+σ Ga 1-σ O3(ZnO) M (where 0 < σ < 1, M is a number from 1 to 3), and the overall composition is In P Ga Q O R ( ZnO) M (where 0 < P < 2, 0 < Q < 2, M is a number from 1 to 3), which is preferred. is preferred.

[0159] Also, when using an oxide semiconductor layer containing CAAC-OS, the layer in contact with the lower surface of the oxide semiconductor layer is preferably flat. For example, the average surface roughness of the layer in contact with the lower surface of the oxide semiconductor layer containing CAAC-OS is preferably 1 nm or less, and more preferably 0.3 nm or less. When the layer in contact with the lower surface of the oxide semiconductor layer containing CAAC-OS is flattened, the mobility can be improved to be higher than that of an oxide semiconductor that is entirely amorphous. For example, by one or more of chemical mechanical polishing (CMP) treatment and plasma treatment, the layer in contact with the lower surface of the oxide semiconductor layer containing CAAC-OS can be flattened. At this time, the plasma treatment includes a process of sputtering the surface with a rare gas ion and a process of etching the surface using an etching gas. is included. By improving the flatness of the layer in contact with the lower surface of the oxide semiconductor layer containing CAAC-OS, the mobility can be improved to be higher than that of an oxide semiconductor that is entirely amorphous. For example, by one or more of chemical mechanical polishing (CMP) treatment and plasma treatment, the layer in contact with the lower surface of the oxide semiconductor layer containing CAAC-OS can be flattened. At this time, the plasma treatment includes a process of sputtering the surface with a rare gas ion and a process of etching the surface using an etching gas. is included. When an oxide semiconductor layer containing CAAC-OS is used in a field-effect transistor, the variation in the electrical characteristics of the field-effect transistor due to irradiation with visible light or ultraviolet light is suppressed, so that a highly reliable field-effect transistor can be obtained. is included. is included.

[0160] Furthermore, in regions 404a and 404b shown in FIG. 8(B), dopants are added, and the electric characteristics of the field-effect transistor are less likely to vary due to irradiation with visible light or ultraviolet light, so a highly reliable field-effect transistor can be obtained. is obtained.

[0161] Furthermore, in regions 404a and 404b shown in FIG. 8(B), dopants are added, and the electric It functions as the source or drain of a field-effect transistor. As dopants, for example, elements of Group 13 in the periodic table (such as boron), elements of Group 15 in the periodic table (such as one or more of nitrogen, phosphorus, and arsenic), and one or more of noble gas elements (such as one or more of helium, argon, and xenon) can be used. Also, a region having the function of the source of a field-effect transistor is also referred to as a source region, and a region having the function of the drain of a field-effect transistor is also referred to as a drain region. By adding dopants to region 404a and region 404b, the resistance between the conductive layers can be reduced.

[0162] Each of conductive layer 405a_A, conductive layer 405b_A, conductive layer 405a_B, and conductive layer 405b_ B functions as the source or drain of a field-effect transistor. Also, a layer having the function of the source of a field-effect transistor is also referred to as a source electrode or a source wiring, and a layer having the function of the drain of a field-effect transistor is also referred to as a drain electrode or a drain wiring.

[0163] As conductive layer 405a_A, conductive layer 405b_A, conductive layer 405a_B, and conductive layer 405b_ B, for example, a metal material such as aluminum, magnesium, chromium, copper, tantalum, titanium, molybdenum, tungsten, or a layer (single layer or laminate) of an alloy material having these metal materials as the main components can be used.

[0164] Also, conductive layer 405a_A, conductive layer 405b_A, conductive layer 405a_B, and conductive layer 40 As 5b_B, a layer containing a conductive metal oxide can also be used. As the conductive metal oxide, for example, indium oxide, tin oxide, zinc oxide, indium tin oxide, or indium zinc oxide can be used. Note that the conductive metal oxide applicable to the conductive layer 405a_A, the conductive layer 405b_A, the conductive layer 405a_B, and the conductive layer 405b_B may contain silicon oxide.

[0165] As the insulating layer 406, for example, a layer (single layer or laminate) of a material applicable to the insulating layer 402_A can be used.

[0166] As the insulating layer 407, for example, a layer (single layer or laminate) of a material applicable to the insulating layer 402_A can be used.

[0167] Also, when an oxide semiconductor layer is used as the semiconductor layer 403_A or the semiconductor layer 403_B, for example, dehydration and dehydrogenation are performed to remove impurities such as hydrogen, water, hydroxyl groups, or hydrides ( also referred to as hydrogen compounds) in the oxide semiconductor layer, and oxygen is supplied to the oxide semiconductor layer to purify the oxide semiconductor layer. For example, by using a layer containing oxygen as the layer in contact with the oxide semiconductor layer and performing heat treatment, the oxide semiconductor layer can be highly purified. For example, heat treatment is performed at a temperature of 400°C or higher and 750°C or lower, or at a temperature of 400°C or higher and lower than the strain point of the substrate. Further, heat treatment may be performed in subsequent steps. At this time, as the heat treatment apparatus for performing the above heat treatment, for example, an electric furnace or a device that heats the object to be processed by heat conduction or heat radiation from a heating element such as a resistance heating element can be used. For example, GRTA (G

[0168] For example, heat treatment is carried out at a temperature of 400 °C or higher and 750 °C or lower, or at a temperature of 400 °C or higher and lower than the distortion point of the substrate. Further, heat treatment may be carried out in subsequent steps. At this time, as the heat treatment apparatus for carrying out the above heat treatment, for example, an electric furnace or a device that heats the object to be processed by heat conduction or heat radiation from a heating element such as a resistance heating element can be used. For example, GRTA (G processing is carried out at a temperature of 400 °C or higher and 750 °C or lower, or at a temperature of 400 °C or higher and lower than the distortion point of the substrate. Further, heat treatment may be carried out in subsequent steps. At this time, as the heat treatment apparatus for carrying out the above heat treatment, for example, an electric furnace or a device that heats the object to be processed by heat conduction or heat radiation from a heating element such as a resistance heating element can be used. For example, GRTA (G treatment device, for example, an electric furnace or a device that heats the object to be processed by heat conduction or heat radiation from a heating element such as a resistance heating element can be used, for example, GRTA (G transfer or heat radiation from a heating element such as a resistance heating element to heat the object to be processed can be used, for example, GRTA (G devices such as Rapid Thermal Anneal) or LRTA (Lamp Ra pid Thermal Anneal) devices such as RTA (Rapid Therma l Anneal) devices can be used. The LRTA device is, for example, a halogen lamp , a metal halide lamp, a xenon arc lamp, a carbon arc lamp, a high-pressure sodium lamp, or a high-pressure mercury lamp, etc. It is a device that heats the object to be processed by the radiation of light (electromagnetic waves) emitted from a lamp. Also, the GRTA device is a device that performs heat treatment using high-temperature gas. As the high-temperature gas, for example, noble gas or an inert gas (such as nitrogen) that does not react with the object to be processed by heat treatment can be used.

[0169] Also, after the above heat treatment, while maintaining the heating temperature or during the process of cooling down from the heating temperature to the same furnace as the furnace where the heat treatment was performed, high-purity oxygen gas, high-purity N2O gas, or ultra-dry air (atmosphere with a dew point of -40°C or lower, preferably -60°C or lower) may be introduced. At this time, it is preferable that the oxygen gas or N2O gas does not contain water, hydrogen, etc. Also, the purity of the oxygen gas or N2O gas introduced into the heat treatment device is 6N or higher, preferably 7 N or higher, that is, the impurity concentration in the oxygen gas or N2O gas is 1 ppm or lower, preferably 0.1 ppm or lower. Due to the action of the oxygen gas or N2O gas, oxygen is supplied to the oxide semiconductor layer, and defects caused by oxygen deficiency in the oxide semiconductor layer can be reduced. Note that the introduction of the above high-purity oxygen gas, high-purity N2O gas, or ultra-dry air may be performed during the above heat treatment.

[0170] Also, when forming an oxide semiconductor layer containing CAAC-OS, a sputtering method is used, the temperature of the device formation layer on which the oxide semiconductor film is formed is set to 100°C or higher and 600°C or lower, preferably 150°C or higher and 550°C or lower, more preferably 200°C or higher and 500°C or lower, to form an oxide semiconductor film. By increasing the temperature of the device formation layer to form an oxide semiconductor film, the atomic arrangement in the oxide semiconductor film is ordered and densified, and polycrystal or CAAC-OS is easily formed. Further, by forming the film in an oxygen gas atmosphere, since there are no extra atoms such as noble gas, polycrystal or CAAC-OS is easily formed. However, a mixed atmosphere of oxygen gas and noble gas may also be used. In that case, the ratio of oxygen gas is 30 vol% or more preferably 50 vol% or more, more preferably 80 vol% or more.

[0171] By using the highly purified oxide semiconductor layer for a field effect transistor, the carrier density of the oxide semiconductor layer can be made less than 1×10 14 / cm 3 preferably less than 1×10 12 / cm 3 more preferably less than 1×10 11 / cm 3 -17 -18 The off-current of the field effect transistor per 1 μm channel width can be made 10 aA (1×10 -17 A) or less, further 1 aA (1×10 -18 A) or less, further 10 zA (1×10 -20 A) or less, further 1 zA (1×10 -21 A) or less, further 100 yA (1×10 -22 A) or less. The lower the off-current of the field effect transistor, the better. However, in this embodiment, ​The lower limit value of the off-current of the field-effect transistor is estimated to be about 10 -30 A / μm.

[0172] As described with reference to FIG. 8, an example of the field-effect transistor in the present embodiment can be applied to the field-effect transistor in the semiconductor device or the light-emitting device of the above embodiment to form a semiconductor device or a light-emitting device.

[0173] (Embodiment 5) In this embodiment, a structural example of the light-emitting device will be described. Here, as an example, it is assumed that the configuration of the light-emitting device is the circuit configuration shown in FIG. 2(A).

[0174] The light-emitting device in the present embodiment includes a first substrate (also referred to as an active matrix substrate) provided with semiconductor elements such as field-effect transistors, a second substrate, and a light-emitting element provided between the first substrate and the second substrate.

[0175] First, a structural example of the active matrix substrate in the light-emitting device of the present embodiment will be described with reference to FIG. 9. FIG. 9 is a diagram showing a structural example of the active matrix substrate in the light-emitting device of the present embodiment. FIG. 9(A) is a plan schematic view. FIG. 9(B) is a cross-sectional schematic view of the line segment A-B in FIG. 9(A). FIG. 9(C) is a cross-sectional schematic view of the line segment C-D in FIG. 9(A). Note that in FIG. 9, components having dimensions different from the actual ones are included. For convenience, in FIG. 9(B), a part of the cross-section of the line segment A-B in FIG. 9(A) is omitted. In FIG. 9(C), a part of the cross-section of the line segment C-D in FIG. 9(A) is omitted.

[0176] ​​​​​​​​​​​​​The active matrix substrate shown in FIG. 9 includes a substrate 500 and conductive layers 511a to 51 1h, the insulating layer 512, the semiconductor layers 513a to 513h, and the conductive layers 515a to The semiconductor device includes a conductive layer 515l, an insulating layer 516, a conductive layer 517a, and a conductive layer 517b.

[0177] Each of the conductive layers 511 a to 511 h is provided on one surface of the substrate 500 .

[0178] The conductive layer 511a is, for example, in the field effect transistor 111 of the light emitting device shown in FIG. the gate in the field effect transistor 114, the gate in the field effect transistor 116 the gate of the field effect transistor 117, and the wiring 153. It has functions.

[0179] The conductive layer 511b is, for example, in the field effect transistor 112 of the light emitting device shown in FIG. functions as a gate in the semiconductor device, a gate in the field effect transistor 115, and a wiring 154; has.

[0180] The conductive layer 511c has a function as, for example, the wiring 156 of the light-emitting device shown in FIG. .

[0181] The conductive layer 511d is, for example, in the field effect transistor 113 of the light emitting device shown in FIG. It functions as the first gate in the

[0182] The conductive layer 511e is, for example, a pair of electrodes in the capacitor 121 of the light-emitting device shown in FIG. The second electrode functions as the other of the pair of electrodes of the capacitor 122 .

[0183] The conductive layer 511f has a function as, for example, the wiring 157 of the light-emitting device shown in FIG. .

[0184] The conductive layer 511g functions as a gate in the field-effect transistor 118 of the light-emitting device shown in FIG. 2(A), for example, and as a wiring 155.

[0185] The conductive layer 511h functions as a wiring 158 of the light-emitting device shown in FIG. 2(A), for example. .

[0186] The insulating layer 512 is provided over the conductive layers 511a to 511h. The insulating layer 512 functions as a gate insulating layer in the field-effect transistors 111 to 118 of the light-emitting device shown in FIG. 2(A), for example, and as a dielectric layer in the capacitor elements 121 and 122.

[0187] The semiconductor layer 513a overlaps the conductive layer 511a with the insulating layer 512 therebetween. The semiconductor layer 513 a functions as a channel-forming layer in the field-effect transistor 111 of the light-emitting device shown in FIG. 2(A), for example.

[0188] The semiconductor layer 513b overlaps the conductive layer 511b with the insulating layer 512 therebetween. The semiconductor layer 513 b functions as a channel-forming layer in the field-effect transistor 112 of the light-emitting device shown in FIG. 2(A), for example.

[0189] The semiconductor layer 513c overlaps the conductive layer 511a with the insulating layer 512 therebetween. The semiconductor layer 513 c functions as a channel-forming layer in the field-effect transistor 116 of the light-emitting device shown in FIG. 2(A), for example.

[0190] The semiconductor layer 513d overlaps the conductive layer 511d with the insulating layer 512 therebetween. The semiconductor layer 513 ​​​​d functions as a channel formation layer in the field-effect transistor 113 of the light-emitting device shown in FIG. 2(A), for example. It has the function as a formation layer.

[0191] The semiconductor layer 513e overlaps the conductive layer 511b with the insulating layer 512 interposed therebetween. The semiconductor layer 513 e functions as a channel formation layer in the field-effect transistor 115 of the light-emitting device shown in FIG. 2(A), for example. It has the function as a formation layer.

[0192] The semiconductor layer 513f overlaps the conductive layer 511a with the insulating layer 512 interposed therebetween. The semiconductor layer 513 f functions as a channel formation layer in the field-effect transistor 117 of the light-emitting device shown in FIG. 2(A), for example. It has the function as a formation layer.

[0193] The semiconductor layer 513g overlaps the conductive layer 511a with the insulating layer 512 interposed therebetween. The semiconductor layer 513 g functions as a channel formation layer in the field-effect transistor 114 of the light-emitting device shown in FIG. 2(A), for example. It has the function as a formation layer.

[0194] The semiconductor layer 513h overlaps the conductive layer 511g with the insulating layer 512 interposed therebetween. The semiconductor layer 513 h functions as a channel formation layer in the field-effect transistor 118 of the light-emitting device shown in FIG. 2(A), for example. It has the function as a formation layer.

[0195] The conductive layer 515a is electrically connected to the semiconductor layer 513a. The conductive layer 515a functions as, for example, one of the source and drain in the field-effect transistor 111 of the light-emitting device shown in FIG. 2(A), and also functions as the wiring 151. It has the function as one of the source and drain in the field-effect transistor 111 of the light-emitting device shown in FIG. 2(A), and also functions as the wiring 151.

[0196] The conductive layer 515b is electrically connected to the semiconductor layer 513a and the semiconductor layer 513b. Also , the conductive layer 515b overlaps with the conductive layer 511e with the insulating layer 512 therebetween. The conductive layer 515b functions as, for example, one of the source and drain in the field-effect transistor 111 of the light-emitting device shown in Fig. 2(A), one of the source and drain in the field-effect transistor 112, and one of a pair of electrodes in the capacitor element 121.

[0197] The conductive layer 515c is electrically connected to the semiconductor layer 513c. Also, the conductive layer 515c is electrically connected to the conductive layer 511c at an opening provided through the insulating layer 512. The conductive layer 515c functions as, for example, one of the source and drain in the field-effect transistor 116 of the light-emitting device shown in Fig. 2(A).

[0198] The conductive layer 515d is electrically connected to the semiconductor layer 513b. Also, the conductive layer 515d overlaps with the semiconductor layer 513c. Further, the conductive layer 515d is provided through the insulating layer 512 and is electrically connected to the conductive layer 511d at an opening. The conductive layer 515d functions as, for example, the other of the source and drain in the field-effect transistor 112 of the light-emitting device shown in Fig 2(A), and also functions as the other of the source and drain in the field-effect transistor 116.

[0199] The conductive layer 515e is electrically connected to the semiconductor layers 513d, 513e, and 513g. The conductive layer 515e functions as, for example, one of the source and drain in the field-effect transistor 113 of the light-emitting device shown in Fig. 2(A), one of the source and drain in the field-effect transistor 114, and the other of the source and drain in the field-effect transistor 115. ​​​​​​

[0200] The conductive layer 515f is electrically connected to the semiconductor layer 513d. Further, the conductive layer 515f is electrically connected to the conductive layer 511e at an opening provided through the insulating layer 512 . The conductive layer 515f functions as, for example, the other of the source and drain in the field effect transistor 113 of the light emitting device shown in Fig. 2(A).

[0201] The conductive layer 515g is electrically connected to the semiconductor layer 513e. The conductive layer 515g functions as, for example one of the source and drain in the field effect transistor 115 of the light emitting device shown in Fig. 2(A), as well as a wiring 152.

[0202] The conductive layer 515h is electrically connected to the semiconductor layer 513g. Further, the conductive layer 515h overlaps the conductive layer 511e with the insulating layer 512 interposed therebetween. The conductive layer 515h functions as, for example, Fig. 2(A) the other of the source and drain in the field effect transistor 114 of the light emitting device shown, as well as one of the pair of electrodes in the capacitor element 122.

[0203] The conductive layer 515i is electrically connected to the semiconductor layer 513h. Further, the conductive layer 515i is electrically connected to the conductive layer 511h at an opening provided through the insulating layer 512 . The conductive layer 515i functions as, for example, one of the source and drain in the field effect transistor 118 of the light emitting device shown in Fig. 2(A).

[0204] The conductive layer 515j is electrically connected to the semiconductor layer 513h. The conductive layer 515j functions as, for example the other of the source and drain in the field effect transistor 118 of the light emitting device shown in Fig. 2(A).

[0205] The conductive layer 515k is electrically connected to the semiconductor layer 513f. Further, the conductive layer 515k is electrically connected to the conductive layer 511f at an opening provided through the insulating layer 512 . The conductive layer 515k functions as, for example, one of the source and drain in the field-effect transistor 117 of the light-emitting device shown in Fig. 2(A).

[0206] The conductive layer 515l is electrically connected to the semiconductor layer 513f. Further, the conductive layer 515l is electrically connected to the conductive layer 511e at an opening provided through the insulating layer 512 . The conductive layer 515l functions as, for example, the other of the source and drain in the field-effect transistor 117 of the light-emitting device shown in Fig. 2(A).

[0207] The insulating layer 516 is provided over the semiconductor layers 513a to 513h and the conductive layers 515a to 515l.

[0208] The conductive layer 517a overlaps the semiconductor layer 513d with the insulating layer 516 interposed therebetween. Further, the conductive layer 5 17a is electrically connected to the conductive layer 515h and the conductive layer 515j at an opening provided through the insulating layer 516. The conductive layer 517a functions as, for example, the second gate in the field-effect transistor 113 of the light-emitting device shown in Fig. 2(A).

[0209] The conductive layer 517b is electrically connected to the conductive layer 515f at an opening provided through the insulating layer 516 .

[0210] Furthermore, a structural example of the light-emitting device in this embodiment will be described with reference to Fig. 10. Fig. 1 0 is a schematic cross-sectional view showing a structural example of a light-emitting device in the present embodiment. In the present embodiment the light-emitting element in the light-emitting device has a structure in which light is emitted in the upper surface direction, but the present invention is not limited to this, and a structure in which light is emitted in the lower surface direction may also be used.

[0211] The light-emitting device shown in FIG. 10 includes, in addition to the active matrix substrate shown in FIG. 9, an insulating layer 518 and , a conductive layer 519, an insulating layer 521, a light-emitting layer 522, a conductive layer 523, a substrate 524, , a coloring layer 525, an insulating layer 526, and an insulating layer 527.

[0212] The insulating layer 518 is provided on the insulating layer 516, the conductive layer 517a, and the conductive layer 517b .

[0213] The conductive layer 519 is provided on the insulating layer 518. Further, the conductive layer 519 is electrically connected to the conductive layer 517b at an opening provided through the insulating layer 518. The conductive layer 51 9 has a function as, for example, one of the anode and the cathode of the light-emitting element 140 shown in FIG. 2(A). 9 has a function as, for example, one of the anode and the cathode of the light-emitting element 140 shown in FIG. 2(A). function.

[0214] The insulating layer 521 is provided on the conductive layer 519.

[0215] The light-emitting layer 522 is electrically connected to the conductive layer 519 at an opening provided in the insulating layer 521. The light-emitting layer 522 has a function as, for example, the light-emitting layer of the light-emitting element 140 shown in FIG. 2(A). The light-emitting layer 522 has a function as, for example, the light-emitting layer of the light-emitting element 140 shown in FIG. 2(A). function.

[0216] The conductive layer 523 is electrically connected to the light-emitting layer 522. The conductive layer 523 has a function as, for example, the other of the anode and the cathode of the light-emitting element 140 shown in FIG. 2(A ).

[0217] In an example of the light-emitting device according to the present embodiment, the structure of the light-emitting element is configured to emit light in the upward direction. However, the present invention is not limited to this, and the structure may be configured to emit light in the downward direction. It is possible.

[0218] The coloring layer 525 is provided on one plane of the substrate 524 so as to transmit light of a specific wavelength among the light from the light-emitting layer 522. It is provided on one plane of the substrate 524.

[0219] The insulating layer 526 is provided on one plane of the substrate 524 with the coloring layer 525 interposed therebetween.

[0220] The insulating layer 527 is provided between the insulating layer 526 and the conductive layer 523.

[0221] Furthermore, each component of the light-emitting device described with reference to FIGS. 9 and 10 will be described.

[0222] As the substrates 500 and 524, for example, a glass substrate or a plastic substrate can be used. Note that the substrates 500 and 524 do not necessarily have to be provided. Note that the substrates 500 and 524 do not necessarily have to be provided.

[0223] As the conductive layers 511a to 511h, for example, a layer (single layer or laminate) of a material applicable to the conductive layer 401_A shown in FIG. 8(A) can be used. It can be used.

[0224] As the insulating layer 512, for example, a layer (single layer or laminate) of a material applicable to the insulating layer 402_A shown in FIG. 8(A) can be used. It can be used.

[0225] As the semiconductor layers 513a to 513h, for example, a layer of a material applicable to the semiconductor layer 403_A shown in FIG. 8(A) can be used. It can be used.

[0226] As the conductive layers 515a to 515l, for example, the conductive layer 405a_ shown in FIG. 8(A) A and a layer (single layer or laminate) of a material applicable to the conductive layer 405b_A can be used. .

[0227] As the insulating layer 516, for example, a layer (single layer or laminate) of a material applicable to the insulating layer 406 shown in Fig. 8(A) can be used. layer or laminate) can be used.

[0228] As the conductive layers 517a and 517b, for example, a layer (single layer or laminate) of a material applicable to the conductive layers 511a to 511h can be used.

[0229] As the insulating layer 518, for example, a layer (single layer or laminate) of a material applicable to the insulating layer 512 can be used. can be used.

[0230] As the conductive layer 519, for example, a layer of a material applicable to the conductive layers 511a to 511h (single layer or laminate) can be used.

[0231] As the insulating layer 521, for example, an organic insulating layer or an inorganic insulating layer can be used.

[0232] The light-emitting layer 522 is a layer that emits light presenting light of a specific color. As the light-emitting layer 522, for example, a light-emitting layer using a light-emitting material that emits light presenting a specific color can be used. Also, the light-emitting layer 522 may be constituted by using a laminate of light-emitting layers that emit light presenting colors with different characteristics. As the light-emitting material, an electroluminescence material such as a fluorescent material or a phosphorescent material can be used. Also, a material containing a plurality of electroluminescence materials can be used to constitute the light-emitting material. For example, a layer of a fluorescent material that emits light presenting blue, a first phosphorescent material layer that emits light presenting orange, and a second phosphorescent material layer that emits light presenting orange can be used. A light-emitting layer 522 that emits white light may be formed by laminating layers. Also, As the electroluminescent material, an organic electroluminescent material or an inorganic electroluminescent material can be used. Further, in addition to the above light-emitting layer, for example, one or more of a hole injection layer, a hole transport layer, an electron transport layer, and an electron injection layer may be provided to form the light-emitting layer.

[0233] As the conductive layer 523, for example, a layer (single layer or laminate) of a material applicable to the conductive layers 511a to 511h that transmits light can be used.

[0234] As the coloring layer 525, for example, a layer that transmits light having a wavelength presenting red, a wavelength presenting green, or a wavelength presenting blue and contains a dye or a pigment can be used. Also, as the coloring layer 525, a layer that transmits light presenting a color of cyan, magenta, or yellow and contains a dye or a pigment may be used. For example, the coloring layer 525 is formed using, for example, photolithography, printing method, inkjet method, electrodeposition method, or electrophotography method. For example, by using the inkjet method, it can be manufactured at room temperature, at low vacuum, or on a large substrate. Also, since it can be manufactured without using a resist mask, the manufacturing cost and the number of manufacturing processes can be reduced.

[0235] As the insulating layer 526, for example, a layer (single layer or laminate) of a material applicable to the insulating layer 512 can be used. Note that the insulating layer 526 does not necessarily have to be provided, but by providing the insulating layer 526 the intrusion of impurities from the coloring layer 525 into the light-emitting element can be suppressed.

[0236] ​​As the insulating layer 527, for example, a layer (single layer or laminate) of a material applicable to the insulating layer 512 or a layer of a resin material can be used.

[0237] As described with reference to FIGS. 9 and 10, in an example of the light-emitting device according to the present embodiment, a light-emitting element that emits light exhibiting a specific color, and a coloring layer that transmits light having a specific wavelength among the light emitted by the light-emitting element are provided. Thereby, since a color image can be displayed without forming a plurality of light-emitting elements that emit light having different colors, the manufacturing process can be facilitated and the yield can be improved. For example, since the light-emitting element can be manufactured without using a metal mask, the manufacturing process becomes easy. In addition, the contrast of the image can be improved.

[0238] (Embodiment 6) In the present embodiment, an example of an electronic device will be described.

[0239] A configuration example of the electronic device according to the present embodiment will be described with reference to FIGS. 11(A) to 11(C) and FIG. 12. FIGS. 11(A) to 11(C) and FIG. 12 are schematic diagrams for explaining a configuration example of the electronic device according to the present embodiment.

[0240] The electronic device shown in FIG. 11(A) is an example of a portable information terminal. The information terminal shown in FIG. 11(A) includes a housing 1001a and a display unit 1002a provided on the housing 1001a.

[0241] Note that one or more connection terminals for connecting to an external device may be provided on a side surface 1003a of the housing 1001a, and one or more of the buttons for operating the portable information terminal shown in FIG. 11 (A) may be provided.

[0242] The portable information terminal shown in Fig. 11(A) includes a CPU, a main memory, an interface for transmitting and receiving signals between an external device, the CPU, and the main memory, and an antenna for transmitting and receiving signals with an external device, inside the housing 1001a. Note that one or more integrated circuits having specific functions may be provided inside the housing 1001a.

[0243] The portable information terminal shown in Fig. 11(A) has functions as one or more of, for example, a telephone, an e - book, a personal computer, and a gaming machine.

[0244] The electronic device shown in Fig. 11(B) is an example of an installation - type information terminal. The installation - type information terminal shown in Fig. 11(B) includes a housing 1001b and a display unit 1002b provided on the housing 1001b.

[0245] Note that the display unit 1002b can also be provided on the deck portion 1008 of the housing 1001b.

[0246] Also, the installation - type information terminal shown in Fig. 11(B) includes a CPU, a main memory, and an interface for transmitting and receiving signals between an external device, the CPU, and the main memory, inside the housing 1001b. Note that one or more integrated circuits having specific functions may be provided inside the housing 1001c. Also, an antenna for transmitting and receiving signals with the outside may be provided for the installation - type information terminal shown in Fig. 11(B).

[0247] Furthermore, one or more of a ticket output unit for outputting tickets, a coin insertion unit, and a bill insertion unit may be provided on the side surface 1003b of the housing 1001b of the installation - type information terminal shown in Fig. 11(B).

[0248] ​​​​​​​The installed information terminal shown in Fig. 11(B) is, for example, a cash dispenser, an information communication terminal (also referred to as a multimedia station) for placing orders for tickets, etc., or a function as a gaming machine. It has.

[0249] Fig. 11(C) is an example of an installed information terminal. The installed information terminal shown in Fig. 11(C) includes a housing 1001c and a display unit 1002c provided on the housing 1001c. Note that a support base for supporting the housing 1001c may be provided.

[0250] In addition, one or more connection terminals for connecting to an external device may be provided on the side surface 1003c of the housing 1001c, and one or more of the buttons for operating the installed information terminal shown in Fig. 11(C) may be provided.

[0251] Further, the installed information terminal shown in Fig. 11(C) may include a CPU, a main memory, and an interface for transmitting and receiving signals between the external device and the CPU and the main memory inside the housing 1001c. In addition, one or more integrated circuits having specific functions may be provided inside the housing 1001c. Also, an antenna for transmitting and receiving signals to and from the outside may be provided on the installed information terminal shown in Fig. 11(C).

[0252] The installed information terminal shown in Fig. 11(C) has functions as, for example, a digital photo frame, an output monitor, or a television device.

[0253] For example, the configuration of the light-emitting device in the above embodiment can be used for, for example, the display unit of an electronic device, and the light-emitting device in Embodiment 2 above can be used as the display units 1002a to 1002c shown in Figs. 11(A) to 11(C).

[0254] Furthermore, the electronic device shown in FIG. 12 is an example of a foldable information terminal. FIG. 12(A) is an external view diagram, and FIG. 12(B) is a block diagram.

[0255] As shown in FIG. 12(A), the electronic device shown in FIG. 12 includes a housing 6000a, a housing 6000 b, a panel 6001a, a panel 6001b, a shaft portion 6002, a button 6003, a connection terminal 6004, and a recording medium insertion portion 6005. Also, as shown in FIG. 12, the electronic device includes a power supply unit 6101, a wireless communication unit 6102, an arithmetic unit 6 103, a sound unit 6104, and a panel unit 6105, as shown in FIG. 12(B).

[0256] The panel 6001a is provided on the housing 6000a.

[0257] The panel 6001b is provided on the housing 6000b. Also, the housing 6000b is connected to the housing 6000a by a shaft portion 60 02.

[0258] The panels 6001a and 6001b have a function as a display panel. For example, different images or a continuous image may be displayed on the panels 6001a and 6001b.

[0259] As the panels 6001a and 6001b, the light-emitting device in the above Embodiment 2 can be used.

[0260] Also, one or both of the panels 6001a and 6001b may have a function as a touch panel. At this time, for example, an image of a keyboard is displayed on one or both of the panels 6001a and 6001b, and a finger 6010 or the like touches the image of the keyboard. ​ It may also perform an input operation. Further, the display panel and the touch panel may be laminated to form one or both of Panel 60 01a and Panel 6001b. Further, an input / output panel including a display circuit and a light detection circuit may be used to form one or both of Panel 6001a and Panel 6001b.

[0261] In the electronic device shown in FIG. 12, since there is a shaft portion 6002, for example, by moving the housing 6000a or the housing 6 000b so that the housing 6000a is superimposed on the housing 6000b, the electronic device can be folded.

[0262] The button 6003 is provided on the housing 6000b. Note that the button 600 3 may be provided on the housing 6000a. Further, a plurality of buttons 6003 may be provided on one or both of the housing 6000a and the housing 6000b. For example, by providing the button 6003 which is a power button, it is possible to control whether to turn on the electronic device by pressing the button 6003.

[0263] The connection terminal 6004 is provided on the housing 6000a. Note that the connection terminal 6 004 may be provided on the housing 6000b. Further, a plurality of connection terminals 6004 may be provided on one or both of the housing 6000a and the housing 600 0b. For example, by connecting the personal computer and the electronic device via the connection terminal 6004, the personal computer may rewrite the content of the data stored in the electronic device.

[0264] The recording medium insertion portion 6005 is provided on the housing 6000a. Note that the recording medium insertion portion 6005 may be provided on the housing 6000b. Further, a plurality of recording medium insertion portions 6005 may be provided on the housing 600 ​​​​​It may be provided on one or both of 0a and the housing 6000b. For example, a card is inserted into the recording medium insertion part By inserting the card-type recording medium, data can be read from the card-type recording medium to the electronic device , or data in the electronic device can be written to the card-type recording medium.

[0265] In addition, the power supply unit 6101 has a function of controlling the supply of power for operating the electronic device . For example, power is supplied from the power supply unit 6101 to the wireless communication unit 6102, the arithmetic unit 6103, the audio unit 6104, and the panel unit 6105. The power supply unit 6101 includes, for example, a power storage device . The power storage device is provided inside one or both of the housing 6000a and the housing 6000b. Note that a power supply circuit for generating a power supply voltage for operating the electronic device may be provided in the power supply unit 6101 . At this time, the power supply voltage is generated in the power supply circuit using the power supplied by the power storage device . Also, the power supply unit 6101 may be connected to a commercial power supply.

[0266] The wireless communication unit 6102 has a function of transmitting and receiving radio waves. For example, the wireless communication unit 6102 includes an antenna, a demodulation circuit, a modulation circuit, etc. At this time, for example, data exchange with the outside is performed using the transmission and reception of radio waves by the antenna . Note that a plurality of antennas may be provided in the wireless communication unit 6102 .

[0267] The arithmetic unit 6103 has a function of performing arithmetic processing according to command signals input from, for example, the wireless communication unit 6102, the audio unit 6104, and the panel unit 6105 . For example, the arithmetic unit 6103 is provided with a CPU, a logic circuit, a memory circuit, etc.

[0268] The audio unit 6104 has a function of controlling the input and output of sounds that are audio data. For example, the audio The section 6104 is provided with a speaker and a microphone.

[0269] The power supply section 6101, the wireless communication section 6102, the arithmetic section 6103, and the audio section 6104 are provided, for example, inside one or both of the housing 6000a and the housing 6000b.

[0270] The panel section 6105 has a function of controlling the operations of the panel 6001a (also referred to as panel A) and the panel 6001b (also referred to as panel B). Note that a drive circuit for controlling the driving of the panel 6001a and the panel 60 01a and the panel 6001b may be provided in the panel section 6105 to control the operations in the panel 6001a and the panel 6001b.

[0271] Note that a control circuit may be provided in one or more of the power supply section 6101, the wireless communication section 6102, the arithmetic section 6103, the audio section 6104, and the panel section 6105 to control the operations by the control circuit. Also, a control circuit may be provided in the arithmetic section 6103, and one or more of the power supply section 6 101, the wireless communication section 6102, the audio section 6104, and the panel section 6105 may be controlled by the control circuit of the arithmetic section 6103.

[0272] Also, a memory circuit may be provided in one or more of the power supply section 6101, the wireless communication section 6102, the audio section 6104, and the panel section 6105 to store data necessary when operating by the memory circuit. This can increase the operation speed.

[0273] Also, the electronic device shown in FIG. 12 can receive power supply from a commercial power supply and can also use the power stored in the power storage device. Therefore, for example, even when power supply cannot be received from the commercial power supply due to a power outage or the like, by using the power storage device as a power supply, the electronic device The machine can be driven.

[0274] By adopting the configuration shown in FIG. 12, the electronic device shown in FIG. 12 can function as, for example, one or more of a telephone, an e-book , a personal computer, and a gaming machine.

[0275] The above is the description of examples of the electronic device in this embodiment.

[0276] As described with reference to FIGS. 11 and 12, an example of the electronic device in this embodiment has a configuration including a panel portion in which the configuration of the light-emitting device in the above embodiment is used.

[0277] Further, in an example of the electronic device in this embodiment, either one or more of a photoelectric conversion unit that generates a power supply voltage according to the incident illuminance and an operation unit that operates the electronic device may be provided on the housing . For example, by providing the photoelectric conversion unit, an external power supply becomes unnecessary, so that the electronic device can be used for a long time even in a place where there is no external power supply .

Description of Reference Numerals

[0278] 111 Field-effect transistor 112 Field-effect transistor 113 Field-effect transistor 114 Field-effect transistor 115 Field-effect transistor 116 Field-effect transistor 117 Field-effect transistor 118 Field-effect transistor 121 Capacitor 122 Capacitor 123 Capacitor 140 Light-emitting element 151 Wiring 152 Wiring 153 Wiring​ 154 Wiring 155 Wiring 156 Wiring 157 Wiring 158 Wiring 159 Wiring 160 Wiring 400_A Element-Forming Layer 400_B Element-Forming Layer 401_A Conductive Layer 401_B Conductive Layer 402_A Insulating Layer 402_B Insulating Layer 403_A Semiconductor Layer 403_B Semiconductor Layer 404a Region 404b Region 405a_A Conductive Layer 405a_B Conductive Layer 405b_A Conductive Layer 405b_B Conductive Layer 406 Insulating Layer 407 Insulating Layer 500 Substrate 511a Conductive Layer 511b Conductive Layer 511c Conductive Layer 511d Conductive Layer 511e Conductive Layer 511f Conductive Layer 511g Conductive Layer 511h Conductive Layer 512 Insulating Layer 513a Semiconductor Layer 513b Semiconductor Layer 513c Semiconductor Layer 513d Semiconductor Layer 513e Semiconductor Layer 513f Semiconductor Layer 513g Semiconductor Layer 513h Semiconductor Layer 515a Conductive Layer 515b Conductive Layer 515c Conductive Layer 515d Conductive Layer 515e Conductive Layer 515f Conductive Layer 515g conductive layer 515h conductive layer 515i conductive layer 515j conductive layer 515k conductive layer 515l conductive layer 516 insulating layer 517a conductive layer 517b conductive layer 518 insulating layer 519 conductive layer 521 insulating layer 522 light-emitting layer 523 conductive layer 524 substrate 525 coloring layer 526 insulating layer 527 insulating layer 900 light-emitting section 901 driving circuit 902 driving circuit 910 light-emitting circuit 1001a housing 1001b housing 1001c housing 1002a display section 1002b display section 1002c display section 1003a side surface 1003b side surface 1003c side surface 1008 deck section 6000a housing 6000b housing 6001a panel 6001b panel 6002 shaft section 6003 button 6004 connection terminal 6005 recording medium insertion section 6010 finger 6101 power supply section 6102 wireless communication section 6103 arithmetic section 6104 sound section 6105 panel section

Claims

1. A pixel includes a first transistor to a fifth transistor, a light-emitting element, and first wiring to third wiring, wherein the first transistor has a first gate electrode and a second gate electrode, one of a source and a drain of the second transistor is electrically connected to the first wiring to which a data signal is supplied, the other of the source and the drain of the second transistor is electrically connected to the first gate electrode, one of a source and a drain of the third transistor is electrically connected to a pixel electrode of the light-emitting element, the other of the source and the drain of the third transistor is electrically connected to the second wiring to which a first potential is supplied, one of a source and a drain of the fourth transistor is electrically connected to one of the source and the drain of the first transistor, the other of the source and the drain of the fourth transistor is electrically connected to the third wiring, one of a source and a drain of the fifth transistor is electrically connected to the second gate electrode, the fifth transistor has a function of supplying a second potential to the second gate electrode, the first transistor has a function of controlling a current flowing between the third wiring and the pixel electrode of the light-emitting element according to a potential of the data signal, and includes a first conductive film to a third conductive film, wherein the first conductive film has a function as the other of the source and the drain of the second transistor, the third conductive film is electrically connected to the second gate electrode, the second conductive film is electrically connected to the pixel electrode of the light-emitting element, and a capacitance formed between the second conductive film and the third conductive film is larger than a capacitance formed between the second conductive film and the first conductive film. A light-emitting device.

2. A pixel includes a first transistor to a fifth transistor, a light-emitting element, and first wiring to third wiring, wherein the first transistor has a first gate electrode having a region disposed below a channel formation region of the first transistor and a second gate electrode having a region disposed above the channel formation region of the first transistor, one of a source and a drain of the second transistor is electrically connected to the first wiring to which a data signal is supplied, the other of the source and the drain of the second transistor is electrically connected to the first gate electrode, One of the source or drain of the third transistor is electrically connected to the pixel electrode of the light-emitting element, The other of the source or drain of the third transistor is electrically connected to the second wiring to which the first potential is supplied, One of the source or drain of the fourth transistor is electrically connected to one of the source or drain of the first transistor, The other of the source or drain of the fourth transistor is electrically connected to the third wiring, One of the source or drain of the fifth transistor is electrically connected to the second gate electrode, The fifth transistor has a function of supplying a second potential to the second gate electrode, The first transistor has a function of controlling a current flowing between the third wiring and the pixel electrode of the light-emitting element according to the potential of the data signal, Having a first conductive film to a third conductive film, The first conductive film has a function as the other of the source or drain of the second transistor, The third conductive film is electrically connected to the second gate electrode, The second conductive film is electrically connected to the pixel electrode of the light-emitting element, The capacitance formed between the second conductive film and the third conductive film is larger than the capacitance formed between the second conductive film and the first conductive film, Light-emitting device.

3. In claim 1 or claim 2, Each of the first transistor to the fifth transistor has an n-channel type, Light-emitting device.

4. In claim 3, The third wiring has a function of supplying a third potential to the pixel, The third potential is higher than the first potential, Light-emitting device.

Images