Communication device

Abstract

To provide a communication device that can transmit and receive signals with a high potential.SOLUTION: A multicoupler includes first to fourth transistors, a transmission terminal, a reception terminal, an antenna terminal, and first and second control terminals. The transmission terminal is electrically connected to one of a source and a drain of the first and second transistors. The reception terminal is electrically connected to one of a source and a drain of the third and fourth transistors. The antenna terminal is electrically connected to the other of the source and drain of the second and fourth transistors. The first control terminal is electrically connected to gates of the second and third transistors. The second control terminal is electrically connected to gates of the first and fourth transistors. Each semiconductor of the first to fourth transistors includes metal oxide.SELECTED DRAWING: Figure 1

Description

Technical Field

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

[0002] Note that one aspect of the present invention is not limited to the above technical field. The technical field of the invention disclosed in this specification and the like relates to an article, a method, or a manufacturing method. Or, one aspect of the present invention relates to a process, a machine, a manufacture, or a composition of matter.

Background Art

[0003] The spread of portable information terminals typified by smartphones and tablet terminals has been progressing. Along with the spread of information terminals, various communication standards have been established. For example, the operation of the LTE-Advanced standard called the fourth-generation mobile communication system (4G) has been started.

[0004] In recent years, due to the development of information technologies such as IoT (Internet of Things), the amount of data handled by information terminals has tended to increase. Also, an improvement in communication speed is required for electronic devices such as information terminals.

[0005] In order to support various information technologies such as IoT, a new communication standard called the fifth-generation mobile communication system (5G) that realizes a communication speed faster than 4G, a large number of simultaneous connections, and a short delay time is being studied. In 5G, communication frequencies in the 3.7 GHz band, 4.5 GHz band, and 28 GHz band are used.

[0006] Communication devices compatible with 5G are manufactured using semiconductors mainly composed of one type of element such as Si, or compound semiconductors mainly composed of a plurality of types of elements such as Ga and As. Furthermore, an oxide semiconductor which is a kind of metal oxide has attracted attention.

[0007] In oxide semiconductors, a CAAC (c-axis aligned crystalline) structure and an nc (nanocrystalline) structure, which are neither single crystals nor amorphous, have been found (see Non-Patent Document 1 and Non-Patent Document 2).

[0008] Non-Patent Document 1 and Non-Patent Document 2 disclose a technique for manufacturing a transistor using an oxide semiconductor having a CAAC structure.

Prior Art Documents

Non-Patent Documents

[0009]

Non-Patent Document 1

Non-Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0010] As the communication frequency increases, the attenuation of radio waves increases, so the reach of the signal carried by the radio waves becomes shorter. Therefore, when the communication frequency is high, it is preferable to increase the amplitude of the potential of the signal.

[0011] One aspect of the present invention aims to provide a communication device capable of transmitting and receiving high-potential signals. Or, one aspect of the present invention aims to provide a communication device that can be used in a high-frequency band. Or, one aspect of the present invention aims to provide a communication device capable of accurately transmitting and receiving signals. Or, one aspect of the present invention aims to provide a small-sized communication device. Or, one aspect of the present invention aims to provide a highly reliable communication device. Or, one aspect of the present invention aims to provide a novel communication device.

[0012] Note that the description of these problems does not prevent the existence of other problems. Note that one aspect of the present invention does not need to solve all of these problems. Note that other problems will become apparent from the descriptions in the specification, drawings, claims, etc., and it is possible to extract these other problems from the descriptions in the specification, drawings, claims, etc.

Means for Solving the Problems

[0013] One aspect of the present invention includes a first transistor, a second transistor, a third transistor, a fourth transistor, a transmission terminal, a reception terminal, an antenna terminal, a first control terminal, and a second control terminal. The transmission terminal is electrically connected to one of the source or drain of the first transistor and one of the source or drain of the second transistor. The reception terminal is electrically connected to one of the source or drain of the third transistor and one of the source or drain of the fourth transistor. The antenna terminal is electrically connected to the other of the source or drain of the second transistor and the other of the source or drain of the fourth transistor. The first control terminal is electrically connected to the gate of the second transistor and the gate of the third transistor. The second control terminal is electrically connected to the gate of the first transistor and the gate of the fourth transistor. The semiconductors of the first to fourth transistors each contain a metal oxide, and it is a communication device.

[0014] Alternatively, in the above aspect, the potential of the other of the source or drain of the first and third transistors is the reference potential, the first to fourth transistors each have a function of a switch, and when turning on the second and third transistors, the potential of the gates of the second and third transistors is set to the first potential, and when turning off the second and third transistors, the potential of the gates of the second and third transistors is set to the second potential. The difference between the first potential and the reference potential is 2V or more, and the second potential may be smaller than the reference potential.

[0015] Alternatively, in the above aspect, when transmitting the first signal from the transmission terminal to the antenna terminal, the potential of the gates of the second and third transistors is set to the first potential, and the potential of the gates of the first and fourth transistors is set to the second potential. When transmitting the second signal from the antenna terminal to the reception terminal, the potential of the gates of the second and third transistors may be set to the second potential, and the potential of the gates of the first and fourth transistors may be set to the first potential.

[0016] Alternatively, in the above aspect, the second potential may be a negative potential.

[0017] Alternatively, one aspect of the present invention is a communication device having a substrate, a first insulator, a second insulator, a first conductor, a second conductor, a third conductor, a fourth conductor, a fifth conductor, a sixth conductor, a seventh conductor, an eighth conductor, a ninth conductor, a tenth conductor, a first semiconductor, a second semiconductor, a third semiconductor, a fourth semiconductor, a transmission terminal, an antenna terminal, a reception terminal, a first control terminal, and a second control terminal. On the substrate, the first insulator is provided. On the first insulator, the first conductor is provided. On the first conductor, the second insulator is provided. On the second insulator, for the first transistor, one of the second conductor and the third conductor serves as a source or a drain, the fourth conductor has a gate function, and a channel formation region is formed in the first semiconductor; for the second transistor, one of the third conductor and the fifth conductor serves as a source or a drain, the sixth conductor has a gate function, and a channel formation region is formed in the second semiconductor; for the third transistor, one of the fifth conductor and the seventh conductor serves as a source or a drain, the eighth conductor has a gate function, and a channel formation region is formed in the third semiconductor; for the fourth transistor, one of the seventh conductor and the ninth conductor serves as a source or a drain, the tenth conductor has a gate function, and a channel formation region is formed in the fourth semiconductor. The first conductor has a region overlapping with the third conductor, the fifth conductor, and the seventh conductor. The first to fourth semiconductors each contain a metal oxide. The transmission terminal is electrically connected to the third conductor. The antenna terminal is electrically connected to the fifth conductor. The reception terminal is electrically connected to the seventh conductor. The first control terminal is electrically connected to the fourth conductor and the eighth conductor. The second control terminal is electrically connected to the sixth conductor and the tenth conductor.

[0018] Alternatively, in the above aspect, the potentials of the second and ninth conductors are the reference potential, the first to fourth transistors each have a function of a switch, when turning on the first and third transistors, the potentials of the fourth and eighth conductors are set to the first potential, when turning off the first and third transistors, the potentials of the fourth and eighth conductors are set to the second potential, the difference between the first potential and the reference potential is 2 V or more, and the second potential may be smaller than the reference potential.

[0019] Alternatively, in the above aspect, when transmitting the first signal from the transmission terminal to the antenna terminal, the fourth and eighth conductors are set to the second potential, and the sixth and tenth conductors are set to the first potential, when transmitting the second signal from the antenna terminal to the reception terminal, the fourth and eighth conductors may be set to the first potential, and the sixth and tenth conductors may be set to the second potential.

[0020] Alternatively, in the above aspect, the second potential may be a negative potential.

[0021] Alternatively, in the above aspect, the potential of the first conductor may be the reference potential.

[0022] Alternatively, in the above aspect, the metal oxide may contain at least one of In or Zn.

[0023] Alternatively, a communication device according to an aspect of the present invention and an electronic device including a speaker, a microphone, or a secondary battery are also an aspect of the present invention.

Advantages of the Invention

[0024] According to an aspect of the present invention, a communication device capable of transmitting and receiving a high-potential signal can be provided. Alternatively, a communication device that can be used in a high-frequency band can be provided. Alternatively, a communication device capable of accurately transmitting and receiving signals can be provided. Alternatively, a small-sized communication device can be provided. Alternatively, a highly reliable communication device can be provided. Alternatively, a novel communication device can be provided.

[0025] Note that the description of these effects does not preclude the existence of other effects. Note that one aspect of the present invention does not necessarily have all of these effects. Note that other effects will be apparent from the description in the specification, drawings, claims, etc., and it is possible to extract these other effects from the description in the specification, drawings, claims, etc.

Brief Description of the Drawings

[0026]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Embodiments for Carrying Out the Invention

[0027] The embodiments will be described in detail with reference to the drawings. However, the present invention is not limited to the following description, and it will be easily understood by those skilled in the art that the form and details thereof can be variously changed without departing from the spirit and scope of the present invention. Therefore, the present invention should not be construed as being limited to the description of the embodiments shown below. In the configuration of the invention described below, the same reference numerals are commonly used among different drawings for the same part or parts having the same or similar functions, and the repeated description thereof will be omitted.

[0028] In addition, the positions, sizes, ranges, etc. of the respective components shown in the drawings and the like may not represent the actual positions, sizes, ranges, etc. in order to facilitate the understanding of the invention. Therefore, the disclosed invention is not necessarily limited to the positions, sizes, ranges, etc. disclosed in the drawings and the like. For example, in an actual manufacturing process, a resist mask or the like may unintentionally become thinner due to a process such as etching, but this may not be reflected in the drawing for the sake of easy understanding.

[0029] In addition, in a top view (also referred to as a "plan view") or a perspective view, etc., for the sake of clarity of the drawing, the description of some components may be omitted.

[0030] In addition, in this specification and the like, the terms "electrode" and "wiring" do not functionally limit these components. For example, an "electrode" may be used as part of a "wiring", and vice versa. Furthermore, the terms "electrode" and "wiring" also include cases where a plurality of "electrodes" and "wirings" are integrally formed.

[0031] In addition, in this specification and the like, the "terminal" in an electric circuit refers to a part where current input or output, voltage input or output, or signal reception or transmission is performed. Therefore, a part of a wiring or an electrode may function as a terminal.

[0032] Note that in this specification and the like, the terms "upper" and "lower" do not limit the positional relationship of the components to be directly above or below and in direct contact. For example, in the expression "electrode B on insulator A", it is not necessary for electrode B to be directly formed on insulator A, and those including other components between insulator A and electrode B are not excluded.

[0033] In addition, the functions of the source and drain are interchangeable depending on operating conditions such as when transistors with different polarities are employed or when the direction of current changes in circuit operation. Therefore, it is difficult to limit which one is the source or the drain. For this reason, in this specification, the terms "source" and "drain" are assumed to be interchangeable.

[0034] In addition, in this specification and the like, "electrically connected" includes both the case of direct connection and the case of connection via "something having some electrical effect". Here, "something having some electrical effect" is not particularly limited as long as it enables the transfer of electrical signals between the connection targets. Therefore, even when expressed as "electrically connect", in an actual circuit, there may be a case where there is no physical connection part and only wiring extends.

[0035] Also, for example, radio waves can be transmitted without being connected by wiring. For example, when transmitting radio waves generated by an AC power source to an antenna, the AC power source and the antenna do not necessarily need to be physically connected by wiring or the like. Even in this case, it can be said that the AC power source and the antenna are electrically connected. That is, even between elements that are not physically connected, there may be a case where they can be said to be electrically connected.

[0036] In addition, in this specification and the like, "parallel" means, for example, a state in which two straight lines are arranged at an angle of -10° or more and 10° or less. Therefore, the case of -5° or more and 5° or less is also included. Also, "perpendicular" and "orthogonal" mean, for example, a state in which two straight lines are arranged at an angle of 80° or more and 100° or less. Therefore, the case of 85° or more and 95° or less is also included.

[0037] Note that in this specification and the like, when referring to count values and measurement values as "identical", "the same", "equal", or "uniform", etc., unless otherwise specified, they include an error of plus or minus 20%.

[0038] Also, voltage often indicates the potential difference between a certain potential and a reference potential (e.g., ground potential or source potential). Therefore, voltage and potential can often be used interchangeably. In this specification and the like, unless otherwise explicitly stated, it is assumed that voltage and potential can be used interchangeably.

[0039] Note that even when referred to as a "semiconductor", for example, when its conductivity is sufficiently low, it has the characteristics of an "insulator". Therefore, it is also possible to use "semiconductor" replaced by "insulator". In this case, the boundary between "semiconductor" and "insulator" is ambiguous, and it is difficult to strictly distinguish between the two. Therefore, the "semiconductor" and "insulator" described in this specification may be able to be read as each other in some cases.

[0040] Also, even when referred to as a "semiconductor", for example, when its conductivity is sufficiently high, it has the characteristics of a "conductor". Therefore, it is also possible to use "semiconductor" replaced by "conductor". In this case, the boundary between "semiconductor" and "conductor" is ambiguous, and it is difficult to strictly distinguish between the two. Therefore, the "semiconductor" and "conductor" described in this specification may be able to be read as each other in some cases.

[0041] Note that ordinal numbers such as "first" and "second" in this specification and the like are attached to avoid confusion of components, and do not indicate any order or rank such as process order or stacking order. Also, even for terms without ordinal numbers in this specification and the like, ordinal numbers may be attached in the claims to avoid confusion of components. Also, even for terms with ordinal numbers in this specification and the like, different ordinal numbers may be attached in the claims. Also, even for terms with ordinal numbers in this specification and the like, ordinal numbers may be omitted in the claims and the like.

[0042] In this specification and the like, the "on state" of a transistor refers to a state in which the source and drain of the transistor can be regarded as being electrically short-circuited (also referred to as the "conductive state"). Further, the "off state" of a transistor refers to a state in which the source and drain of the transistor can be regarded as being electrically disconnected (also referred to as the "non-conductive state").

[0043] In this specification and the like, the "on-current" may refer to the current flowing between the source and drain when the transistor is in the on state. Also, the "off-current" may refer to the current flowing between the source and drain when the transistor is in the off state.

[0044] In this specification and the like, the gate refers to part or all of the gate electrode and the gate wiring. The gate wiring refers to the wiring for electrically connecting the gate electrode of at least one transistor to another electrode or another wiring.

[0045] In this specification and the like, the source refers to part or all of the source region, the source electrode, and the source wiring. The source region refers to a region in the semiconductor where the resistivity is below a certain value. The source electrode refers to the conductor part connected to the source region. The source wiring refers to the wiring for electrically connecting the source electrode of at least one transistor to another electrode or another wiring.

[0046] In this specification and the like, the drain refers to part or all of the drain region, the drain electrode, and the drain wiring. The drain region refers to a region in the semiconductor where the resistivity is below a certain value. The drain electrode refers to the conductor part connected to the drain region. The drain wiring refers to the wiring for electrically connecting the drain electrode of at least one transistor to another electrode or another wiring.

[0047] (Embodiment 1) A communication device according to one aspect of the present invention will be described with reference to the drawings. FIG. 1A is a block diagram showing a configuration example of a wireless transceiver 10, which is a type of communication device.

[0048] Note that the configuration of the communication device exemplified in this specification and the like is just an example, and it is not necessary to include all the components. The communication device only needs to have the necessary components among the components shown in this specification and the like. Also, it may have components other than the components shown in this specification and the like.

[0049] The wireless transceiver 10 includes an antenna 11, a duplexer 20, a control circuit 21, a local oscillator 23, a power amplifier 31, a band-pass filter 32, a mixer 33, a band-pass filter 34, a modulator 35, a low-noise amplifier 41, a band-pass filter 42, a mixer 43, a band-pass filter 44, and a demodulator 45.

[0050] The duplexer 20 has an antenna terminal ANT, a transmission terminal Tx, a reception terminal Rx, a control terminal CTLa, and a control terminal CTLb. The antenna terminal ANT is electrically connected to the antenna 11. The transmission terminal Tx is electrically connected to the power amplifier 31. The reception terminal Rx is electrically connected to the low-noise amplifier 41. The control terminal CTLa and the control terminal CTLb are electrically connected to the control circuit 21. Note that the control terminal CTLa and the control terminal CTLb may be electrically connected to different control circuits.

[0051] The duplexer 20 has a function of realizing transmission and reception of wireless signals with one antenna. The control circuit 21 has a function of controlling the operation of the duplexer 20. Specifically, it has a function of generating potentials to be supplied to the control terminal CTLa and the control terminal CTLb.

[0052] The modulator 35 has a function of generating a basic signal for transmitting a control signal, a data signal, etc. from the wireless transceiver 10 to another communication device, a base station, or the like. The basic signal is supplied to the mixer 33 via the band-pass filter 34.

[0053] The band-pass filter 34 has a function of removing noise components generated when the modulator 35 generates a basic signal.

[0054] The mixer 33 has a function of mixing the basic signal that has passed through the band-pass filter 34 and the signal 36 generated by the local oscillator 23 in a superheterodyne method. The mixer 33 mixes the basic signal and the signal 36 and supplies a signal having frequency components of the difference and the sum of the two to the band-pass filter 32.

[0055] The band-pass filter 32 has a function of passing one of the two frequency components. For example, it passes the sum frequency component. Also, the band-pass filter 32 has a function of removing noise components generated in the mixer 33. The signal that has passed through the band-pass filter 32 is supplied to the power amplifier 31.

[0056] The power amplifier 31 has a function of amplifying the supplied signal to generate the signal 30. The signal 30 is radiated to the outside from the antenna 11 via the duplexer 20.

[0057] A signal 40 transmitted from another communication device or a base station etc. is input to the low-noise amplifier 41 as a received signal via the antenna 11 and the duplexer 20.

[0058] The low-noise amplifier 41 has a function of amplifying a weak received signal to a signal having an intensity that can be processed by the radio transceiver 10. The signal 40 amplified by the low-noise amplifier 41 is supplied to the mixer 43 via the band-pass filter 42.

[0059] The band-pass filter 42 has a function of attenuating frequency components outside the necessary frequency band from among the frequency components included in the signal 40 and passing the frequency components of the necessary frequency band.

[0060] The mixer 43 has the function of mixing the signal 40 that has passed through the band-pass filter 42 and the signal 46 generated by the local oscillator 23 in a superheterodyne manner. The mixer 43 mixes the signal 40 and the signal 46 and supplies a signal having the frequency components of the difference and the sum of the two to the band-pass filter 44.

[0061] The band-pass filter 44 has the function of passing one of the two frequency components. For example, it passes the frequency component of the difference. Also, the band-pass filter 44 has the function of removing the noise components generated in the mixer 43. The signal that has passed through the band-pass filter 44 is supplied to the demodulator 45. The demodulator 45 has the function of converting the supplied signal into a control signal, a data signal, etc. and outputting it. The signal output from the demodulator 45 is supplied to various processing devices (arithmetic devices, storage devices, etc.).

[0062] FIG. 1B is a circuit diagram showing a configuration example of the multiplexer 20. The multiplexer 20 includes a transistor 51, a transistor 52, a resistor 53, a resistor 54, a transistor 61, a transistor 62, a resistor 63, and a resistor 64.

[0063] The transmission terminal Tx is electrically connected to one of the source or drain of the transistor 51 and one of the source or drain of the transistor 52. The reception terminal Rx is electrically connected to one of the source or drain of the transistor 61 and one of the source or drain of the transistor 62. The antenna terminal ANT is electrically connected to the other of the source or drain of the transistor 52 and the other of the source or drain of the transistor 62.

[0064] The gate of transistor 51 is electrically connected to one terminal of resistor 53. The gate of transistor 52 is electrically connected to one terminal of resistor 54. The gate of transistor 61 is electrically connected to one terminal of resistor 63. The gate of transistor 62 is electrically connected to one terminal of resistor 64. Also, control terminal CTLa is electrically connected to the other terminal of resistor 54 and the other terminal of resistor 63. Control terminal CTLb is electrically connected to the other terminal of resistor 53 and the other terminal of resistor 64.

[0065] Here, even if, for example, A and B are connected via a resistor, it can be said that A and B are electrically connected. Thus, it can be said that control terminal CTLa is electrically connected to the gate of transistor 52 and the gate of transistor 61. Also, it can be said that control terminal CTLb is electrically connected to the gate of transistor 51 and the gate of transistor 62.

[0066] A fixed potential can be supplied to the other of the source or drain of transistor 51 and the other of the source or drain of transistor 61. For example, a ground potential can be supplied. Note that a negative potential may be supplied to the other of the source or drain of transistor 51 and the other of the source or drain of transistor 61. Here, the potential supplied to the other of the source or drain of transistor 51 and the other of the source or drain of transistor 61 can be used as a reference potential.

[0067] In the following, the description will be made assuming that a ground potential is supplied to the other of the source or drain of transistor 51 and the other of the source or drain of transistor 61. That is, the description will be made assuming that the reference potential is the ground potential.

[0068] Figures 2A and 2B are circuit diagrams showing an example of the operation method of the wireless transceiver 10. In Figures 2A and 2B, when a transistor is in the off state, an "×" symbol is added superimposed on the transistor. Note that the same notation may be used in other figures as well.

[0069] Figure 2A is a circuit diagram showing an example of the state of the multiplexer 20 when the wireless transceiver 10 transmits the signal 30 to the outside of the wireless transceiver 10, that is, when the wireless transceiver 10 performs a transmission operation.

[0070] As shown in Figure 2A, when the wireless transceiver 10 transmits the signal 30 to the outside of the wireless transceiver 10, the transistors 52 and 61 are turned on, and the transistors 51 and 62 are turned off. In this case, the potential of the gate of the transistor 52 and the potential of the gate of the transistor 61 are set as the potential V1, and the potential of the gate of the transistor 51 and the potential of the gate of the transistor 62 are set as the potential V2. In the case shown in Figure 2A, the potential of the control terminal CTLa is a potential such that the potential of the gate of the transistor 52 and the potential of the gate of the transistor 61 become the potential V1. Also, the potential of the control terminal CTLb is a potential such that the potential of the gate of the transistor 51 and the potential of the gate of the transistor 62 become the potential V2.

[0071] As a result, the transmission terminal Tx and the antenna terminal ANT are electrically connected, and the signal 30 is transmitted from the transmission terminal Tx to the antenna terminal ANT. Since the transistor 61 is in the on state, the potential of the reception terminal Rx becomes the potential of the other of the source or drain of the transistor 61. For example, as shown in Figure 2A, the potential of the reception terminal Rx becomes the ground potential GND. Thereby, since the operation of a circuit electrically connected to the reception terminal Rx, such as the low-noise amplifier 41, can be stopped, malfunction of the wireless transceiver 10 can be suppressed.

[0072] FIG. 2B is a circuit diagram showing an example of the state of the multiplexer 20 when the wireless transceiver 10 receives the signal 40 from outside the wireless transceiver 10, that is, when the wireless transceiver 10 performs a receiving operation.

[0073] As shown in FIG. 2B, when the wireless transceiver 10 receives the signal 40 from outside the wireless transceiver 10, the transistor 51 and the transistor 62 are turned on, and the transistor 52 and the transistor 61 are turned off. In this case, the potential of the gate of the transistor 51 and the potential of the gate of the transistor 62 are set as the potential V1, and the potential of the gate of the transistor 52 and the potential of the gate of the transistor 61 are set as the potential V2. In the case shown in FIG. 2B, the potential of the control terminal CTLa is a potential such that the potential of the gate of the transistor 52 and the potential of the gate of the transistor 61 become the potential V2. Also, the potential of the control terminal CTLb is a potential such that the potential of the gate of the transistor 51 and the potential of the gate of the transistor 62 become the potential V1.

[0074] As described above, the antenna terminal ANT and the reception terminal Rx are electrically connected, and the signal 40 is transmitted from the antenna terminal ANT to the reception terminal Rx. Since the transistor 51 is in the on state, the potential of the transmission terminal Tx becomes the potential of the other of the source or drain of the transistor 51. For example, as shown in FIG. 2B, the potential of the transmission terminal Tx becomes the ground potential GND. Thereby, since the operation of the circuit electrically connected to the transmission terminal Tx, such as the power amplifier 31, can be stopped, malfunction of the wireless transceiver 10 can be suppressed.

[0075] As described above, when the potential V1 is supplied to the gate of the transistor 51, the transistor 51 is turned on; when it is supplied to the gate of the transistor 52, the transistor 52 is turned on; when it is supplied to the gate of the transistor 61, the transistor 61 is turned on; and when it is supplied to the gate of the transistor 62, the transistor 62 is turned on. Also, when the potential V2 is supplied to the gate of the transistor 51, the transistor 51 is turned off; when it is supplied to the gate of the transistor 52, the transistor 52 is turned off; when it is supplied to the gate of the transistor 61, the transistor 61 is turned off; and when it is supplied to the gate of the transistor 62, the transistor 62 is turned off. Therefore, it can be said that the transistors 51, 52, 61, and 62 have the function of a switch, being turned on when the potential of the gate is V1 and turned off when the potential is V2.

[0076] Here, it is preferable that the potential V1 be larger. This will be described with reference to FIGS. 3A and 3B.

[0077] FIGS. 3A and 3B show the potential of the source (S) when a 3V signal is input to the drain (D) of a transistor with a threshold voltage Vth of 1V and the potential of the gate (G) being V1. In the case shown in FIG. 3A, the potential V1 is set to 1V, and in the case shown in FIG. 3B, the potential V1 is set to 5V. In FIGS. 3A and 3B, the on-resistance of the transistor is ignored. Also, in FIGS. 3A and 3B, the direction of the signal flow is indicated by an arrow.

[0078] When the gate voltage Vg, which is the difference between the potential of the gate of the transistor and the potential of the source, is less than the threshold voltage Vth, it can be said that the drain current, which is the current flowing between the drain and the source, stops flowing. Therefore, it is difficult for the potential of the source to be greater than the difference between the potential of the gate and the threshold voltage Vth. Thus, as shown in FIG. 3A, when the difference between the potential of the gate and the potential of the drain is less than the threshold voltage Vth, the potential of the source becomes less than the potential of the drain. Therefore, when the potential of the gate is low, signal potential fluctuations are likely to occur.

[0079] On the other hand, when the potential of the gate is high, even if the potential of the drain is high, it becomes difficult for signal potential fluctuations to occur. As shown in FIG. 3B, when the potential V1, which is the potential of the gate, is 5V, even if the potential of the drain is 3V as in the case shown in FIG. 3A, no signal potential fluctuation occurs, and the potential of the source becomes 3V.

[0080] From the above, the potential V1 supplied to the gate when turning on the transistor is preferably higher. However, if the potential of the gate of the transistor is increased too much, the transistor may be damaged. Also, even if it is not damaged, the reliability of the transistor may decrease. For example, when the potential of the gate of a transistor (also referred to as a "Si transistor") containing silicon in the semiconductor where the channel is formed is set to 5V as shown in FIG. 3B, when the potential of the source of the Si transistor is, for example, 0V, the Si transistor may be damaged or its reliability may decrease. Therefore, if the difference between the potential of the gate of the Si transistor and the reference potential is 5V or more, the Si transistor may be damaged or its reliability may decrease. Also, the Si transistor may be damaged or its reliability may decrease even when the potential of the gate is 2V or more, 1.8V or more, or 1.5V or more. Specifically, even if the difference between the potential of the gate of the Si transistor and the reference potential is 2V or more, 1.8V or more, or 1.5V or more, the Si transistor may be damaged or its reliability may decrease.

[0081] Here, a transistor (also referred to as an "OS transistor") that includes an oxide semiconductor (Oxide Semiconductor: OS), which is a type of metal oxide, in the semiconductor where a channel is formed has a characteristic of having a higher breakdown voltage than, for example, an Si transistor. Therefore, even if the potential of the gate of the OS transistor is set to 5V as shown in FIG. 3B, the OS transistor is not destroyed and its reliability does not decrease.

[0082] In the 5G communication standard, high-frequency bands such as the 3.7 GHz band, 4.5 GHz band, and 28 GHz band are used. Therefore, since the attenuation of radio waves increases, the reach of the signal carried by the radio waves becomes shorter. Thus, when the communication frequency is high, it is preferable to increase the amplitude of the potential of the signal. From the above, when the wireless transceiver 10 particularly supports the 5G communication standard, it is preferable that the transistors 52 and 62 included in the duplexer 20 are OS transistors. Thereby, since the wireless transceiver 10 can transmit and receive signals with a high potential, it can be used in a high-frequency band.

[0083] Here, it is also preferable that the transistors 51 and 61 are OS transistors. That is, it is preferable that all of the transistors 51, 52, 61, and 62 are OS transistors. The reason for this will be described with reference to FIGS. 4A, 4B1, and 4B2.

[0084] FIGS. 4A and 4B1 are circuit diagrams in which the transistors 51 and 52, and the transmission terminal Tx and the antenna terminal ANT are extracted from among the components of the duplexer 20 shown in FIG. 1B.

[0085] FIG. 4A shows the case where the transistor 51 is in the off state and the transistor 52 is in the on state. That is, it shows the case where the wireless transceiver 10 performs a transmission operation.

[0086] In the case shown in FIG. 4A, it is assumed that a signal 30 of 4V is transmitted from the transmission terminal Tx to the antenna terminal ANT. In this case, the potential of the transmission terminal Tx and the potential of the antenna terminal ANT are 4V. Note that potential fluctuations of the signal 30 associated with the transmission of the signal 30 from the transmission terminal Tx to the antenna terminal ANT are not considered.

[0087] As shown in FIG. 4A, when the potential of the transmission terminal Tx is 4V, the voltage Vds, which is the difference between the potential of the drain and the potential of the source of the transistor 51, becomes 4V. Therefore, if the transistor 51 is a low-breakdown-voltage transistor such as an Si transistor, the transistor 51 may be damaged. Further, even if it is not damaged, the reliability of the transistor may decrease. Specifically, when the voltage Vds of the Si transistor is 4V or more, the Si transistor may be damaged or the reliability may decrease. Also, the Si transistor may be damaged or the reliability may decrease even when the voltage Vds is 3V or more, 2V or more, or 1.5V or more. From the above, it is preferable that the transistor 51 is a high-breakdown-voltage transistor such as an OS transistor.

[0088] FIG. 4B1 shows the case where the transistor 51 is in the on state and the transistor 52 is in the off state. That is, it shows the case where the wireless transceiver 10 performs a reception operation.

[0089] In the case shown in FIG. 4B1, the potential of the transmission terminal Tx is, for example, 0V. Here, the potential of the antenna terminal ANT is set to 4V as in the case shown in FIG. 4A. In this case, the voltage Vds of the transistor 52 becomes 4V. Therefore, if the transistor 52 is a low-breakdown-voltage transistor such as an Si transistor, the transistor 52 may be damaged or the reliability may decrease.

[0090] Therefore, when the transistor 52 is, for example, an Si transistor, as shown in FIG. 4B2, it is necessary to provide a plurality of transistors 52 in series and to provide a resistor 72 in parallel with the transistor 52. In the configuration shown in FIG. 4B2, a transistor 52[1] and a transistor 52[2] are provided as the transistors 52, and a resistor 72[1] and a resistor 72[2] are provided as the resistors 72. Then, the antenna terminal ANT is electrically connected to one of the source or drain of the transistor 52[1] and one terminal of the resistor 72[1]. Also, the other of the source or drain of the transistor 52[1] is electrically connected to one of the source or drain of the transistor 52[2], the other terminal of the resistor 72[1], and one terminal of the resistor 72[2]. Further, the transmission terminal Tx is electrically connected to one of the source or drain of the transistor 51, the other of the source or drain of the transistor 52[2], and the other terminal of the resistor 72[2].

[0091] In the case shown in FIG. 4B2, even if the potential of the antenna terminal ANT is 4V and the potential of the transmission terminal Tx is 0V as in the case shown in FIG. 4B1, the voltage Vds of the transistor 52 becomes 2V. Therefore, the voltage Vds of the transistor 52 can be reduced compared to the case shown in FIG. 4B1. However, the number of transistors and the like included in the multiplexer 20 increases, and the occupied area of the multiplexer 20 increases. As a result, the radio transceiver 10 becomes larger. Also, even when the transistor 52 is in the off state, a current flows from the antenna terminal ANT to the transmission terminal Tx via the resistor 72. As a result, the potential of the signal transmitted inside the multiplexer 20 fluctuates, so that the radio transceiver 10 cannot accurately transmit and receive signals.

[0092] On the one hand, the OS transistor is not destroyed even when the voltage Vds is 4 V or higher, and its reliability does not decrease. Specifically, it is not destroyed and its reliability does not decrease if the voltage Vds is 5 V or lower. Alternatively, there is a possibility that it is not destroyed and its reliability does not decrease even when the voltage Vds is 20 V. Therefore, by using the transistor 52 as the OS transistor, the number of transistors 52 provided in the multiplexer 20 can be reduced compared to the case where the transistor 52 is a low breakdown voltage transistor such as a Si transistor. Therefore, the size of the wireless transceiver 10 can be reduced. Also, it is not necessary to provide a resistor 72 connected in parallel with the transistor 52. Thereby, not only can the size of the wireless transceiver 10 be reduced, but also the signal transmission and reception by the wireless transceiver 10 can be performed with high accuracy.

[0093] Note that it is also preferable that the transistors 61 and 62 are OS transistors. The reason for this is that the description using FIGS. 4A, 4B1, and 4B2 can be applied by replacing the transistor 51 with the transistor 61, the transistor 52 with the transistor 62, the transmission terminal Tx with the reception terminal Rx, the signal 30 with the signal 40, and so on.

[0094] Another reason why it is preferable to use transistors 51, 52, 61, and 62 as OS transistors will be explained. OS transistors are characterized by extremely low off-current. Therefore, by using transistors 51, 52, 61, and 62 as OS transistors, it is possible to suppress potential fluctuations of signals transmitted inside the multiplexer 20. Specifically, when signal 30 is transmitted from the transmission terminal Tx to the antenna terminal ANT as shown in Fig. 2A, it is possible to suppress potential fluctuations of signal 30 caused by leakage current flowing through transistors 51 and 62 that are in the off state. Also, when signal 40 is transmitted from the antenna terminal ANT to the reception terminal Rx as shown in Fig. 2B, it is possible to suppress potential fluctuations of signal 40 caused by leakage current flowing through transistors 52 and 61 that are in the off state. As a result, the signal transmission and reception by the wireless transceiver 10 can be performed accurately.

[0095] Here, it is preferable to supply the gate of the transistor in the off state with a potential as low as possible. That is, it is preferable that potential V2 is as low as possible. For example, it is preferable that potential V2 is a potential smaller than the reference potential. For example, when the reference potential is the ground potential, it is preferable that potential V2 is a negative potential. By making potential V2 as low as possible, the leakage current flowing through the transistor in the off state can be reduced. The relationship between the gate potential and the off-current will be explained below.

[0096] Fig. 5A is a graph showing the Id-Vg characteristics of an Si transistor, and Fig. 5B is a graph showing the Id-Vg characteristics of an OS transistor. In Figs. 5A and 5B, the horizontal axis shows the gate voltage Vg, which is the difference between the potential of the gate and the potential of the source, on a linear scale, and the vertical axis shows the drain current Id flowing between the source and the drain on a logarithmic scale.

[0097] As shown in FIG. 5A, when the gate voltage Vg of the Si transistor becomes too small, the drain current Id increases. Specifically, when the gate voltage Vg becomes negative, the drain current Id may increase compared to the case where the gate voltage Vg is 0V. Therefore, for example, if the potential of the gate of the Si transistor is made smaller than the reference potential, the drain current Id, which is the off-current, may become larger compared to the case where the potential of the gate is equal to the reference potential. For example, when the reference potential is the ground potential, if the potential of the gate is made a negative potential, the off-current may become larger compared to the case where the potential of the gate is the ground potential.

[0098] On the other hand, as shown in FIG. 5B, in the OS transistor, the drain current Id continues to decrease even when the gate voltage Vg becomes smaller. Therefore, the gate voltage Vg of the OS transistor can be made smaller. For example, when the potential of the gate of the OS transistor is made smaller than the reference potential, the off-current becomes smaller than the case where the potential of the gate is equal to the reference potential. For example, when the reference potential is the ground potential, if the potential of the gate is made a negative potential, the off-current becomes smaller than the case where the potential of the gate is the ground potential.

[0099] For the reasons described above, the transistors 51, 52, 61, and 62 included in the sharing device 20 are preferably OS transistors.

[0100] Note that at least one of the transistors 51, 52, 61, and 62 may be a transistor having a back gate. FIG. 6A is a circuit diagram showing a configuration example of the sharing device 20 when the transistors 51, 52, 61, and 62 are configured by transistors having a back gate. FIG. 6A shows an example in which the gate and the back gate of the transistor are electrically connected, but one aspect of the present invention is not limited to this. For example, a wiring to which a constant potential is supplied may be electrically connected to the back gate. Alternatively, the potential of the gate of the transistor and the potential of the back gate of the transistor may be independently controlled.

[0101] The back gate is arranged so as to sandwich the channel formation region of the semiconductor between the gate and the back gate. By changing the potential of the back gate, the threshold voltage of the transistor can be changed. The potential of the back gate may be the same as the potential of the gate, or may be the ground potential or an arbitrary potential. Also, the back gate can function in the same way as the gate. Therefore, the gate and the back gate can be used interchangeably. For example, one of the gate or the back gate may be called the "first gate" and the other may be called the "second gate".

[0102] Also, generally, since the gate and the back gate are formed of a conductor, they also have a function (particularly an electrostatic shielding function against static electricity) of preventing the electric field generated outside the transistor from acting on the semiconductor in which the channel is formed. That is, it is possible to suppress fluctuations in the electrical characteristics of the transistor due to the influence of an external electric field such as static electricity.

[0103] Also, an inductor may be provided in at least one of between the gate of the transistor 51 and the resistor 53, between the gate of the transistor 52 and the resistor 54, between the gate of the transistor 61 and the resistor 63, and between the gate of the transistor 62 and the resistor 64. FIG. 6B is a circuit diagram showing a configuration example of the multiplexer 20 in the case where the inductors 55, 56, 65, and 66 are provided. Note that an inductor is also called a coil.

[0104] In the combiner 20 configured as shown in FIG. 6B, one terminal of the inductor 55 is electrically connected to the gate of the transistor 51, and the other terminal of the inductor 55 is electrically connected to one terminal of the resistor 53. Also, one terminal of the inductor 56 is electrically connected to the gate of the transistor 52, and the other terminal of the inductor 56 is electrically connected to one terminal of the resistor 54. Also, one terminal of the inductor 65 is electrically connected to the gate of the transistor 61, and the other terminal of the inductor 65 is electrically connected to one terminal of the resistor 63. Further, one terminal of the inductor 66 is electrically connected to the gate of the transistor 62, and the other terminal of the inductor 66 is electrically connected to one terminal of the resistor 64.

[0105] Here, as described above, even when, for example, A and B are connected via a resistor, it can be said that A and B are electrically connected. Also, even when, for example, A and B are connected via an inductor, it can be said that A and B are electrically connected. Thus, it can be said that the control terminal CTLa is electrically connected to the gates of the transistor 52 and the transistor 61. Also, it can be said that the control terminal CTLb is electrically connected to the gates of the transistor 51 and the transistor 62.

[0106] By configuring the combiner 20 as shown in FIG. 6B, even if the signals 30 transmitted from the transmission terminal Tx to the antenna ANT and the signals 40 transmitted from the antenna terminal ANT to the reception terminal Rx are high-frequency signals, the potential fluctuations of the signals 30 and 40 can be suppressed. Therefore, the signal transmission and reception by the wireless transceiver 10 can be accurately performed. In particular, when the wireless transceiver 10 supports a communication standard in a high-frequency band such as 5G, the signal transmission and reception by the wireless transceiver 10 can be accurately performed.

[0107] FIG. 7A is a diagram showing an example of a cross-sectional configuration of the wireless transceiver 10. FIG. 7A shows the transistors 51, 52, 61, and 62 shown in FIG. 1B and the like. FIG. 8A is a cross-sectional view of the transistor 200, which is a transistor applicable to the transistors 51, 52, 61, and 62, in the channel length direction, and FIG. 8B is a cross-sectional view of the transistor 200 in the channel width direction. As described above, the transistors 51, 52, 61, and 62 are OS transistors. Therefore, the transistor 200 is an OS transistor.

[0108] As shown in FIG. 7A, an insulator 102 is provided on the substrate 100. As the substrate 100, a silicon substrate, a glass substrate, a quartz substrate, a sapphire substrate, a ceramic substrate, a metal substrate (for example, a stainless steel substrate, a substrate having a stainless steel foil, a tungsten substrate, a substrate having a tungsten foil, etc.), a semiconductor substrate (for example, a single crystal semiconductor substrate, a polycrystalline semiconductor substrate, or a compound semiconductor substrate, etc.), an SOI (SOI: Silicon on Insulator) substrate, etc. can be used. Further, a plastic substrate having heat resistance capable of withstanding the processing temperature of the present embodiment may be used. Examples of the glass substrate include barium borosilicate glass, aluminosilicate glass, or aluminoborosilicate glass, or soda lime glass. In addition, crystallized glass or the like can be used.

[0109] Alternatively, as the substrate, a flexible substrate, a laminated film, paper containing fibrous materials, or a base film can be used. Examples of flexible substrates, laminated films, base films, etc. include the following. For example, there are plastics typified by polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), and polytetrafluoroethylene (PTFE). Alternatively, as an example, there are synthetic resins such as acrylic. Alternatively, as an example, there are polypropylene, polyester, polyvinyl fluoride, or polyvinyl chloride. Alternatively, as an example, there are polyamides, polyimides, aramid resins, epoxy resins, inorganic vapor deposition films, or papers. In particular, by manufacturing a transistor using a semiconductor substrate, a single crystal substrate, or an SOI substrate, etc., a transistor with less variation in characteristics, size, or shape, high current capacity, and small size can be manufactured. When a circuit is configured with such a transistor, power consumption reduction or high integration of the circuit can be achieved.

[0110] Also, as the substrate, a flexible substrate can be used, and transistors, resistors, and / or capacitors, etc. may be formed directly on the flexible substrate. Alternatively, a release layer may be provided between the substrate and transistors, resistors, and / or capacitors, etc. The release layer can be used to separate from the substrate after partially or completely completing a communication device thereon and transfer it to another substrate. At that time, transistors, resistors, and / or capacitors, etc. can also be transferred to a substrate with poor heat resistance or a flexible substrate. Note that for the above-mentioned release layer, for example, a laminated structure of inorganic films of a tungsten film and a silicon oxide film, a structure in which an organic resin film such as polyimide is formed on the substrate, a silicon film containing hydrogen, etc. can be used.

[0111] That is, a communication device may be formed on a certain substrate and then transferred to another substrate. As an example of the substrate to which the communication device is transferred, in addition to the substrate on which the above-described transistors can be formed, a paper substrate, a cellophane substrate, an aramid film substrate, a polyimide film substrate, a stone substrate, a wood substrate, a cloth substrate (including natural fibers (silk, cotton, hemp), synthetic fibers (nylon, polyurethane, polyester), or recycled fibers (acetate, cupra, rayon, recycled polyester), etc.), a leather substrate, or a rubber substrate, etc. By using these substrates, it is possible to manufacture a flexible communication device, manufacture a robust communication device, impart heat resistance, reduce weight, or make it thinner.

[0112] By providing a communication device on a flexible substrate, it is possible to suppress an increase in weight and provide a communication device that is not easily damaged.

[0113] An insulator 104 and a conductor 130 are provided on an insulator 102. For example, a reference potential is supplied to the conductor 130. The functions of the conductor 130 will be described later.

[0114] As the material of the conductor 130, a conductive material such as a metal material, an alloy material, a metal nitride material, or a metal oxide material can be used alone or in a laminated manner. It is preferable to use a high melting point material such as tungsten or molybdenum that combines heat resistance and conductivity, and it is more preferable to use tungsten. Alternatively, it is preferable to use a low resistance conductive material such as aluminum or copper. By using a low resistance conductive material, the wiring resistance can be reduced.

[0115] Also, an insulator 106 is provided on the insulator 104 and on the conductor 130. Then, transistors 51, 52, 61, and 62 are provided on the insulator 106.

[0116] As shown in FIGS. 8A and 8B, the transistor 200 includes an insulator 108 on the insulator 106, an insulator 110 on the insulator 108, a conductor 203 disposed so as to be embedded in the insulator 108 and the insulator 110, an insulator 112 disposed on the insulator 110 and on the conductor 203, an insulator 114 disposed on the insulator 112, an insulator 116 disposed on the insulator 114, a metal oxide 230a disposed on the insulator 116, a metal oxide 230b disposed on the metal oxide 230a, two conductors 132 disposed apart from each other on the metal oxide 230b, an insulator 120 disposed on the conductors 132 and having an opening formed by overlapping between the two conductors 132, an insulator 245 disposed on the bottom surface and the side surface of the opening, and a conductor 138 disposed on the formation surface of the insulator 245.

[0117] Also, as shown in FIGS. 8A and 8B, it is preferable that an insulator 118 is disposed between the metal oxide 230a, the metal oxide 230b, the conductor 132, and the insulator 120. Also, as shown in FIGS. 8A and 8B, the conductor 138 preferably includes a conductor 138a provided inside the insulator 245 and a conductor 138b provided so as to be embedded inside the conductor 138a. Also, as shown in FIGS. 8A and 8B, it is preferable that an insulator 122 is disposed on the insulator 120, on the conductor 138, and on the insulator 245.

[0118] Note that in this specification and the like, the metal oxide 230a and the metal oxide 230b may be collectively referred to as the metal oxide 230.

[0119] Note that in the transistor 200, a configuration in which two layers of the metal oxide 230a and the metal oxide 230b are stacked in a region where a channel is formed and in its vicinity is shown, but the present invention is not limited to this. For example, a single layer of the metal oxide 230b or a stacked configuration of three or more layers may be used.

[0120] In addition, in the transistor 200, the conductor 138 is shown as a two-layer stacked structure, but the present invention is not limited to this. For example, the conductor 138 may have a single-layer structure or a stacked structure of three or more layers. Also, the transistor 200 shown in FIGS. 8A and 8B is an example and is not limited to its configuration, and an appropriate transistor may be used according to the circuit configuration, operation method, etc.

[0121] Here, the conductor 138 functions as the gate of the transistor 200. Also, one of the two conductors 132 functions as the source of the transistor 200, and the other functions as the drain of the transistor 200.

[0122] In FIG. 7A, the conductor 138 included in the transistor 51 is denoted as conductor 138[1], the conductor 138 included in the transistor 52 is denoted as conductor 138[2], the conductor 138 included in the transistor 62 is denoted as conductor 138[3], and the conductor 138 included in the transistor 61 is denoted as conductor 138[4]. Here, although not shown in FIG. 7A, the conductor 138[1] and the conductor 138[3] are electrically connected to the control terminal CTLb. Also, the conductor 138[2] and the conductor 138[4] are electrically connected to the control terminal CTLa.

[0123] Also, in FIG. 7A, conductors 132a, 132b, 132c, 132d, and 132e are shown as the conductor 132. The conductor 132a functions as the other of the source or drain of the transistor 51. The conductor 132b functions as one of the source or drain of the transistor 51 and one of the source or drain of the transistor 52. The conductor 132c functions as the other of the source or drain of the transistor 52 and the other of the source or drain of the transistor 62. The conductor 132d functions as one of the source or drain of the transistor 62 and one of the source or drain of the transistor 61. The conductor 132e functions as the other of the source or drain of the transistor 61.

[0124] As described above, the conductor 138 is formed to be embedded in the opening of the insulator 120 and the region sandwiched between the two conductors 132. The arrangement of the conductor 138 and the two conductors 132 is self-alignedly selected with respect to the opening of the insulator 120. That is, in the transistor 200, the gate can be self-alignedly arranged between the source and the drain. Therefore, since the conductor 138 can be formed without providing an alignment margin, the occupied area of the transistor 200 can be reduced. Thereby, miniaturization and high integration of the communication device according to one aspect of the present invention can be achieved.

[0125] Furthermore, since the conductor 138 is self-alignedly formed in the region between the two conductors 132, the conductor 138 does not have a region overlapping with the two conductors 132. Thereby, the parasitic capacitance formed between the conductor 138 and the two conductors 132 can be reduced. Therefore, the switching speed of the transistor 200 can be improved, and the frequency characteristics of the communication device according to one aspect of the present invention can be enhanced.

[0126] The conductor 138 may function as a first gate. Also, the conductor 203 may function as a second gate. Here, the conductor 203 is arranged to have a region overlapping with the metal oxide 230 and the conductor 138. Thereby, when a potential is supplied to the conductor 138 and the conductor 203, the electric field generated from the conductor 138 and the electric field generated from the conductor 203 are connected, and the channel formation region formed in the metal oxide 230 can be covered.

[0127] In this specification and the like, a configuration of a transistor in which a channel formation region is electrically surrounded by the electric fields of a pair of gates (a first gate and a second gate) is referred to as a Surrounded channel (S-channel) configuration. Also, the S-channel configuration disclosed in this specification and the like is different from the Fin type configuration and the planar type configuration. By adopting the S-channel configuration, it is possible to enhance the resistance to the short channel effect, in other words, to obtain a transistor in which the short channel effect hardly occurs.

[0128] Further, as shown in FIG. 8A, the conductor 203 has a conductor 203a formed in contact with the inner wall of the opening provided in the insulator 108 and the insulator 110, and a conductor 203b is further formed inside. In the transistor 200, the configuration of laminating the conductor 203a and the conductor 203b is shown, but the present invention is not limited thereto. For example, the conductor 203 may be provided in a single layer or a laminated configuration of three or more layers.

[0129] Here, it is preferable to use a conductive material in which the conductor 203a has a function of suppressing the diffusion of impurities such as hydrogen atoms, hydrogen molecules, water molecules, and copper atoms (the above impurities are difficult to permeate). Alternatively, it is preferable to use a conductive material in which the conductor 203a has a function of suppressing the diffusion of oxygen (for example, at least one of oxygen atoms, oxygen molecules, etc.) (the above oxygen is difficult to permeate). In this specification, the function of suppressing the diffusion of impurities or oxygen means the function of suppressing the diffusion of any one or all of the above impurities or the above oxygen.

[0130] For example, since the conductor 203a has a function of suppressing the diffusion of oxygen, it is possible to suppress the oxidation of the conductor 203b and the decrease in conductivity.

[0131] Further, when the conductor 203 also serves as a wiring function, it is preferable to use a highly conductive material mainly composed of tungsten, copper, or aluminum for the conductor 203b. In the present embodiment, the conductor 203 is illustrated as a laminate of the conductor 203a and the conductor 203b, but the conductor 203 may have a single-layer configuration.

[0132] The insulators 112, 114, and 116 have a function as an insulating film corresponding to the second gate, that is, as a second gate insulating film.

[0133] Here, it is preferable that the insulator 116 has a reduced concentration of impurities such as water or hydrogen in the film. Thereby, for example, it is possible to suppress the incorporation of impurities such as water or hydrogen into the metal oxide 230. Here, when hydrogen diffuses into a semiconductor element having an oxide semiconductor such as the transistor 200, the characteristics of the semiconductor element may deteriorate. From the above, by reducing the concentration of impurities such as water or hydrogen contained in the insulator 116, fluctuations in the electrical characteristics of the transistor 200 can be suppressed.

[0134] Here, it is preferable to use an insulator that contains more oxygen than the oxygen that satisfies the stoichiometric composition for the insulator 116 in contact with the metal oxide 230. The oxygen is likely to be released from the film by heating. In this specification and the like, the oxygen released by heating may be referred to as "excess oxygen". That is, it is preferable that a region containing excess oxygen (also referred to as an "excess oxygen region") is formed in the insulator 116. By providing such an insulator containing excess oxygen in contact with the metal oxide 230, the oxygen vacancies (V O : also referred to as oxygen vacancy) in the metal oxide 230 can be reduced, and the reliability of the transistor 200 can be improved. When hydrogen enters the oxygen vacancies in the metal oxide 230, the defect (hereinafter, sometimes referred to as V O H) may function as a donor, and electrons as carriers may be generated. Also, a part of the hydrogen may combine with the oxygen that binds to the metal atom to generate electrons as carriers. Therefore, a transistor using an oxide semiconductor containing a large amount of hydrogen is likely to have normally-on characteristics. Also, since hydrogen in the oxide semiconductor is likely to move due to stress such as heat or an electric field, if the oxide semiconductor contains a large amount of hydrogen, the reliability of the transistor may deteriorate. In one aspect of the present invention, it is preferable to reduce V O H in the metal oxide 230 as much as possible and make the metal oxide 230 highly pure intrinsic or substantially highly pure intrinsic. Thus, V OIn order to obtain an oxide semiconductor with sufficiently reduced H, it is important to remove impurities such as moisture and hydrogen in the oxide semiconductor (also referred to as "dehydration" or "dehydrogenation treatment"), and to supply oxygen to the oxide semiconductor to compensate for oxygen deficiencies (also referred to as "oxygen addition treatment"). V O By using an oxide semiconductor with sufficiently reduced impurities such as H in the channel formation region of a transistor, stable electrical characteristics can be imparted.

[0135] As the insulator having an excess oxygen region, specifically, it is preferable to use an oxide material in which a part of oxygen is desorbed by heating. The oxide from which oxygen is desorbed by heating is an oxide film in which the desorption amount of oxygen in terms of oxygen atoms is 1.0×10 18 atoms / cm 3 or more, preferably 1.0×10 19 atoms / cm 3 or more, more preferably 2.0×10 19 atoms / cm 3 or more, or 3.0×10 20 atoms / cm 3 or more. The surface temperature of the film during the above TDS analysis is preferably in the range of 100°C or more and 700°C or less, or 100°C or more and 400°C or less.

[0136] Also, any one or more of heat treatment, microwave treatment, or RF treatment may be performed by bringing the insulator having the excess oxygen region into contact with the metal oxide 230. By performing this treatment, water or hydrogen in the metal oxide 230 can be removed. For example, in the metal oxide 230, a reaction in which the bond of VoH is broken occurs, in other words, a reaction of "V O H→Vo+H" occurs, and dehydrogenation can be achieved. A part of the hydrogen generated at this time may be combined with oxygen to form H2O and removed from the metal oxide 230 or the insulator near the metal oxide 230. Also, a part of the hydrogen may be gettered by the conductor 132.

[0137] Further, for the microwave treatment, for example, it is preferable to use a device having a power source for generating high-density plasma or a device having a power source for applying RF to the substrate side. For example, by using a gas containing oxygen and high-density plasma, high-density oxygen radicals can be generated. Then, by applying RF to the substrate side, the oxygen radicals generated by the high-density plasma can be efficiently introduced into the metal oxide 230 or the insulator near the metal oxide 230. Further, for the microwave treatment, the pressure may be 133 Pa or more, preferably 200 Pa or more, and more preferably 400 Pa or more. Further, as the gas introduced into the device for performing the microwave treatment, for example, oxygen and argon are used, and the oxygen flow rate ratio (O2 / (O2+Ar)) is set to 50% or less, preferably 10% or more and 30% or less.

[0138] Further, during the manufacturing process of the transistor 200, it is preferable to perform a heat treatment in a state where the surface of the metal oxide 230 is exposed. The heat treatment may be performed, for example, at 100°C or higher and 450°C or lower, more preferably 350°C or higher and 400°C or lower. The heat treatment is performed in an atmosphere of nitrogen gas or an inert gas, or an atmosphere containing 10 ppm or more, 1% or more, or 10% or more of an oxidizing gas. For example, the heat treatment is preferably performed in an oxygen atmosphere. Thereby, oxygen can be supplied to the metal oxide 230 to reduce oxygen vacancies (V O ). Further, the heat treatment may be performed under reduced pressure. Alternatively, the heat treatment may be performed in an atmosphere containing 10 ppm or more, 1% or more, or 10% or more of an oxidizing gas in order to supplement the desorbed oxygen after heat treatment in an atmosphere of nitrogen gas or an inert gas. Alternatively, after heat treatment in an atmosphere containing 10 ppm or more, 1% or more, or 10% or more of an oxidizing gas, heat treatment may be continuously performed in an atmosphere of nitrogen gas or an inert gas.

[0139] By subjecting the metal oxide 230 to an oxygen addition treatment, it is possible to repair the oxygen deficiency in the metal oxide 230 with the supplied oxygen, in other words, to promote the reaction of "Vo + O → null". Furthermore, by reacting the supplied oxygen with the hydrogen remaining in the metal oxide 230, the hydrogen can be removed (dehydrated) as H2O. As a result, it is possible to suppress the recombination of the hydrogen remaining in the metal oxide 230 with the oxygen deficiency to form V O H.

[0140] Also, when the insulator 116 has an excess oxygen region, it is preferable that the insulator 114 has a function of suppressing the diffusion of oxygen (for example, oxygen atoms, oxygen molecules, etc.) (the oxygen is difficult to permeate).

[0141] It is preferable that the insulator 114 has a function of suppressing the diffusion of oxygen and impurities, so that the oxygen in the metal oxide 230 does not diffuse to the insulator 112 side. Also, it is preferable because the conductor 203 can be suppressed from reacting with the oxygen in the insulator 116 and the metal oxide 230.

[0142] The insulator 114 is preferably a single layer or a laminate of an insulator containing a so-called high-k material such as aluminum oxide, hafnium oxide, an oxide containing aluminum and hafnium (hafnium aluminate), tantalum oxide, zirconium oxide, lead zirconate titanate (PZT), strontium titanate (SrTiO3), or (Ba,Sr)TiO3 (BST). As the miniaturization and high integration of transistors progress, problems such as leakage current may occur due to the thinning of the gate insulating film. By using a high-k material for the insulator functioning as the gate insulating film, it is possible to reduce the gate potential during transistor operation while maintaining the physical film thickness.

[0143] In particular, an insulator containing one or both oxides of aluminum and hafnium, which is an insulating material having a function of suppressing diffusion of impurities and oxygen (wherein oxygen is less permeable), may be used. As the insulator containing one or both oxides of aluminum and hafnium, it is preferable to use aluminum oxide, hafnium oxide, an oxide containing aluminum and hafnium (hafnium aluminate), or the like. When the insulator 114 is formed using such a material, the insulator 114 functions as a layer that suppresses the release of oxygen from the metal oxide 230 and the incorporation of impurities such as hydrogen from the peripheral portion of the transistor 200 into the metal oxide 230.

[0144] Alternatively, for example, aluminum oxide, bismuth oxide, germanium oxide, niobium oxide, silicon oxide, titanium oxide, tungsten oxide, yttrium oxide, or zirconium oxide may be added to these insulators. Alternatively, these insulators may be nitrided. Silicon oxide, silicon oxynitride, or silicon nitride may be laminated and used on the above insulators.

[0145] Also, the insulator 112 is preferably thermally stable. For example, silicon oxide and silicon oxynitride are suitable because they are thermally stable.

[0146] In this specification and the like, silicon oxynitride refers to a material having a higher oxygen content than nitrogen in its composition, and silicon nitride oxide refers to a material having a higher nitrogen content than oxygen in its composition. Also, in this specification and the like, aluminum oxynitride refers to a material having a higher oxygen content than nitrogen in its composition, and aluminum nitride oxide refers to a material having a higher nitrogen content than oxygen in its composition.

[0147] In the transistor 200 of FIGS. 8A and 8B, although the insulator 112, the insulator 114, and the insulator 116 are illustrated as the second gate insulating film having a three-layer stacked structure, the second gate insulating film may have a single-layer, two-layer, or four-layer or more stacked structure. In that case, it is not limited to a stacked structure made of the same material, and a stacked structure made of different materials may also be used.

[0148] The transistor 200 uses a metal oxide that functions as an oxide semiconductor for the metal oxide 230 including the channel formation region. For example, as the metal oxide 230, a metal oxide such as an In-M-Zn oxide (element M is selected from one or more of aluminum, gallium, yttrium, copper, vanadium, beryllium, boron, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, or magnesium, etc.) may be used.

[0149] The formation of the metal oxide that functions as an oxide semiconductor may be performed by a sputtering method or an ALD (Atomic Layer Deposition) method. Note that the metal oxide that functions as an oxide semiconductor will be described in detail in other embodiments.

[0150] In addition, as the metal oxide that functions as the channel formation region in the metal oxide 230, it is preferable to use a metal oxide having a band gap of 2 eV or more, preferably 2.5 eV or more. By using a metal oxide having a large band gap in this way, the off-current of the transistor can be reduced.

[0151] The metal oxide 230 has the metal oxide 230a under the metal oxide 230b, so that the diffusion of impurities from the constituent formed below the metal oxide 230a to the metal oxide 230b can be suppressed.

[0152] Note that the metal oxide 230 preferably has a laminated structure of a plurality of oxide layers with different atomic ratios of each metal atom. Specifically, in the metal oxide used for the metal oxide 230a, the atomic ratio of the element M in the constituent elements is preferably larger than the atomic ratio of the element M in the constituent elements in the metal oxide used for the metal oxide 230b. Further, in the metal oxide used for the metal oxide 230a, the atomic ratio of the element M to In is preferably larger than the atomic ratio of the element M to In in the metal oxide used for the metal oxide 230b. Further, in the metal oxide used for the metal oxide 230b, the atomic ratio of In to the element M is preferably larger than the atomic ratio of In to the element M in the metal oxide used for the metal oxide 230a.

[0153] Further, it is preferable that the energy of the lower end of the conduction band of the metal oxide 230a is higher than the energy of the lower end of the conduction band of the metal oxide 230b. In other words, it is preferable that the electron affinity of the metal oxide 230a is smaller than the electron affinity of the metal oxide 230b.

[0154] Here, at the junction of the metal oxide 230a and the metal oxide 230b, the energy level of the lower end of the conduction band changes smoothly. In other words, it can also be said that the energy level of the lower end of the conduction band at the junction of the metal oxide 230a and the metal oxide 230b changes continuously or is continuously joined. To do this, it is preferable to lower the density of defect energy levels in the mixed layer formed at the interface between the metal oxide 230a and the metal oxide 230b.

[0155] Specifically, by having a common element (as the main component) other than oxygen in the metal oxide 230a and the metal oxide 230b, a mixed layer with a low defect energy level density can be formed. For example, when the metal oxide 230b is an In-Ga-Zn oxide, it is preferable to use an In-Ga-Zn oxide, a Ga-Zn oxide, gallium oxide, etc. as the metal oxide 230a.

[0156] At this time, the main path of the carrier becomes the metal oxide 230b. By configuring the metal oxide 230a as described above, the density of defect levels at the interface between the metal oxide 230a and the metal oxide 230b can be reduced. Therefore, the influence of interface scattering on carrier conduction is reduced, and the transistor 200 can obtain a high on-current.

[0157] On the metal oxide 230b, a conductor 132 that functions as a source and a drain is provided. As the conductor 132, it is preferable to use a metal element selected from aluminum, chromium, copper, silver, gold, platinum, tantalum, nickel, titanium, molybdenum, tungsten, hafnium, vanadium, niobium, manganese, magnesium, zirconium, beryllium, indium, ruthenium, iridium, strontium, lanthanum, or an alloy containing the above-described metal elements as components. For example, it is preferable to use tantalum nitride, titanium nitride, tungsten, a nitride containing titanium and aluminum, a nitride containing tantalum and aluminum, ruthenium oxide, ruthenium nitride, an oxide containing strontium and ruthenium, an oxide containing lanthanum and nickel, etc. Further, tantalum nitride, titanium nitride, a nitride containing titanium and aluminum, a nitride containing tantalum and aluminum, ruthenium oxide, ruthenium nitride, an oxide containing strontium and ruthenium, an oxide containing lanthanum and nickel are preferable because they are conductive materials that are difficult to oxidize or materials that maintain conductivity even when absorbing oxygen. Furthermore, a metal nitride film such as tantalum nitride is preferable because it has a barrier property against hydrogen or oxygen.

[0158] Also, in FIG. 8A, the conductor 132 is shown as a single-layer configuration, but it may also be a laminated configuration of two or more layers. For example, a tantalum nitride film and a tungsten film may be laminated. Also, a titanium film and an aluminum film may be laminated. Also, a two-layer configuration in which an aluminum film is laminated on a tungsten film, a two-layer configuration in which a copper film is laminated on a copper-magnesium-aluminum alloy film, a two-layer configuration in which a copper film is laminated on a titanium film, or a two-layer configuration in which a copper film is laminated on a tungsten film may be used.

[0159] In addition, there are three-layer structures such as a titanium film or a titanium nitride film, on which an aluminum film or a copper film is laminated, and then a titanium film or a titanium nitride film is formed thereon; a molybdenum film or a molybdenum nitride film, on which an aluminum film or a copper film is laminated, and then a molybdenum film or a molybdenum nitride film is formed thereon. Note that a transparent conductive material containing indium oxide, tin oxide, or zinc oxide may be used.

[0160] Also, as shown in FIG. 8A, regions 133 may be formed as low-resistance regions at the interface between the metal oxide 230 and the conductor 132 and in the vicinity thereof. As described above, since the transistor 200 has two conductors 132, the transistor 200 also has two regions 133. One of the two regions 133 functions as one of the source region or the drain region. The other of the two regions 133 functions as the other of the source region or the drain region. A channel formation region is formed in the region sandwiched between the two regions 133.

[0161] By providing the conductor 132 in contact with the metal oxide 230, the oxygen concentration in the region 133 may be reduced. In addition, a metal compound layer containing the metal contained in the conductor 132 and the components of the metal oxide 230 may be formed in the region 133. In such a case, the carrier density in the region 133 increases, and the region 133 becomes a low-resistance region.

[0162] The insulator 118 is provided to cover the conductor 132 and suppress the oxidation of the conductor 132. At this time, the insulator 118 may be provided to cover the side surface of the metal oxide 230 and be in contact with the insulator 116.

[0163] As the insulator 118, a metal oxide containing one or more selected from hafnium, aluminum, gallium, yttrium, zirconium, tungsten, titanium, tantalum, nickel, germanium, neodymium, lanthanum, magnesium, etc. can be used. Further, as the insulator 118, silicon oxynitride, silicon nitride, etc. can also be used.

[0164] In particular, as the insulator 118, it is preferable to use an insulator containing one or both of aluminum oxide, hafnium oxide, an oxide containing aluminum and hafnium (hafnium aluminate), etc., which is an insulator containing one or both of aluminum or hafnium oxides. In particular, hafnium aluminate has higher heat resistance than a hafnium oxide film. Therefore, it is preferable because it is difficult to crystallize in the heat treatment in the subsequent process. Note that when the conductor 132 is a material having oxidation resistance or a material whose conductivity does not significantly decrease even when it absorbs oxygen, the insulator 118 is not an essential component. It may be appropriately designed according to the required transistor characteristics.

[0165] By having the insulator 118, it is possible to suppress the diffusion of impurities such as water and hydrogen contained in the insulator 120 to the metal oxide 230b through the insulator 245. Further, it is possible to suppress the oxidation of the conductor 138 by the excess oxygen possessed by the insulator 120.

[0166] The insulator 245 functions as an insulating film corresponding to the first gate, that is, as the first gate insulating film. The insulator 245 is preferably formed using an insulator that contains oxygen in excess and releases oxygen by heating, similar to the insulator 116 described above.

[0167] Specifically, silicon oxide having excess oxygen, silicon oxynitride, silicon nitride oxynitride, silicon nitride, silicon oxide added with fluorine, silicon oxide added with carbon, silicon oxide added with carbon and nitrogen, silicon oxide having pores can be used. In particular, silicon oxide and silicon oxynitride are preferable because they are stable against heat.

[0168] By providing an insulator containing excess oxygen as insulator 245, oxygen can be effectively supplied from insulator 245 to the channel formation region of metal oxide 230b. Also, similar to insulator 116, it is preferable that the concentration of impurities such as water or hydrogen in insulator 245 is reduced. The film thickness of insulator 245 is preferably 1 nm or more and 20 nm or less.

[0169] Also, in order to efficiently supply the excess oxygen possessed by insulator 245 to metal oxide 230, a metal oxide may be provided between insulator 245 and conductor 138. The metal oxide preferably has a function of suppressing oxygen diffusion from insulator 245 to conductor 138. By providing a metal oxide having a function of suppressing oxygen diffusion, the diffusion of excess oxygen from insulator 245 to conductor 138 is suppressed. That is, a decrease in the amount of excess oxygen supplied to metal oxide 230 can be suppressed. Also, oxidation of conductor 138 by excess oxygen can be suppressed. As the metal oxide, a material that can be used for insulator 118 may be used.

[0170] Note that insulator 245 may have a stacked structure, similar to the second gate insulating film. As the miniaturization and high integration of transistors progress, problems such as leakage current may occur due to the thinning of the gate insulating film. Therefore, by forming an insulator that functions as a gate insulating film into a stacked structure of a high-k material and a thermally stable material, it becomes possible to reduce the gate potential during transistor operation while maintaining the physical film thickness. Also, a stacked structure that is thermally stable and has a high relative dielectric constant can be formed.

[0171] Conductor 138 that functions as the first gate is shown as a two-layer structure in FIGS. 8A and 8B, but it may have a single-layer structure or a stacked structure of three or more layers.

[0172] It is preferable to use a conductive material for the conductor 138a that has a function of suppressing the diffusion of impurities such as hydrogen atoms, hydrogen molecules, water molecules, nitrogen atoms, nitrogen molecules, nitrogen oxide molecules (such as N2O, NO, NO2), and copper atoms. Alternatively, it is preferable to use a conductive material that has a function of suppressing the diffusion of oxygen (for example, at least one of oxygen atoms, oxygen molecules, etc.). By having the function of suppressing the diffusion of oxygen, the conductor 138b can be prevented from being oxidized by the oxygen contained in the insulator 245 and the conductivity from decreasing. As the conductive material having the function of suppressing the diffusion of oxygen, for example, it is preferable to use tantalum, tantalum nitride, ruthenium, or ruthenium oxide. Further, as the conductor 138a, an oxide semiconductor applicable to the metal oxide 230 can be used. In that case, by forming the conductor 138b by sputtering, the electrical resistance value of the conductor 138a can be decreased to make it a conductor. This can be called an OC (Oxide Conductor) electrode.

[0173] Also, for the conductor 138b, it is preferable to use a conductive material mainly composed of tungsten, copper, or aluminum. Further, since the conductor 138b also functions as a wiring, it is preferable to use a conductor with high conductivity. For example, a conductive material mainly composed of tungsten, copper, or aluminum can be used. Also, the conductor 138b may have a laminated structure, for example, a laminated structure of titanium or titanium nitride and the above conductive material may be used.

[0174] Insulator 120 is provided on conductor 132 via insulator 118. Insulator 120 preferably has an excess oxygen region. For example, as insulator 120, it is preferable to have silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, silicon oxide with added fluorine, silicon oxide with added carbon, silicon oxide with added carbon and nitrogen, silicon oxide with pores, or resin, etc. In particular, silicon oxide and silicon oxynitride are preferable because they are thermally stable. In particular, silicon oxide and silicon oxide with pores are preferable because an excess oxygen region can be easily formed in a later process.

[0175] Insulator 120 preferably has an excess oxygen region. By providing insulator 120 that releases oxygen upon heating, oxygen in insulator 120 can be efficiently supplied to metal oxide 230. Note that it is preferable that the concentration of impurities such as water or hydrogen in insulator 120 is reduced.

[0176] The opening of insulator 120 is formed to overlap the region between the two conductors 132. Thereby, conductor 138 is formed to be embedded in the opening of insulator 120 and the region sandwiched between the two conductors 132.

[0177] When miniaturizing a communication device, it is required to shorten the gate length of transistor 200, but on the other hand, it is necessary to prevent the conductivity of conductor 138 from decreasing. As a method of shortening the gate length of transistor 200 while preventing the conductivity of conductor 138 from decreasing, there is a method of increasing the film thickness of conductor 138. When the film thickness of conductor 138 is increased, conductor 138 can have a shape with a high aspect ratio. In the present embodiment, since conductor 138 is provided to be embedded in the opening of insulator 120, even if conductor 138 has a shape with a high aspect ratio, it can be formed without collapsing conductor 138 during the process.

[0178] The insulator 122 is preferably provided in contact with the upper surface of the insulator 120, the upper surface of the conductor 138, and the upper surface of the insulator 245. By forming the insulator 122 by sputtering, an excess oxygen region can be provided in the insulator 245 and the insulator 120. Thereby, oxygen can be supplied from the excess oxygen region into the metal oxide 230.

[0179] For example, as the insulator 122, a metal oxide containing one or more selected from hafnium, aluminum, gallium, yttrium, zirconium, tungsten, titanium, tantalum, nickel, germanium, or magnesium can be used.

[0180] In particular, aluminum oxide has high barrier properties and can suppress the diffusion of hydrogen and nitrogen even in a thin film of 0.5 nm or more and 3.0 nm or less. Therefore, aluminum oxide formed by sputtering can function as an oxygen supply source and also as a barrier film for impurities such as hydrogen.

[0181] Also, it is preferable to provide an insulator 124 that functions as an interlayer film on the insulator 122. Similar to the insulator 116 and the like, the insulator 124 preferably has a reduced concentration of impurities such as water or hydrogen in the film.

[0182] Also, as shown in FIG. 8A, a conductor 134 is disposed in an opening formed in the insulator 124, the insulator 122, the insulator 120, and the insulator 118 and reaching the conductor 132.

[0183] In FIG. 7A, conductors 134a, 134b, 134c, 134d, and 134e are shown as the conductor 134. The conductor 134a is provided on the conductor 132a, the conductor 134b is provided on the conductor 132b, the conductor 134c is provided on the conductor 132c, the conductor 134d is provided on the conductor 132d, and the conductor 134e is provided on the conductor 132e.

[0184] The conductor 134 has the function of a plug or wiring. The conductor 134 can use the same material as the conductor 130.

[0185] Also, as shown in FIG. 7A, a conductor 136a may be provided on the conductor 134a, a conductor 136b may be provided on the conductor 134b, a conductor 136c may be provided on the conductor 134c, a conductor 136d may be provided on the conductor 134d, and a conductor 136e may be provided on the conductor 134e. The conductors 136a to 136e have the function of a plug or wiring.

[0186] Here, a reference potential is supplied to the conductors 136a and 136e. Also, the conductor 136b is electrically connected to the transmission terminal Tx, the conductor 136c is electrically connected to the antenna terminal ANT, and the conductor 136d is electrically connected to the reception terminal Rx. From the above, it can be said that a reference potential is supplied to the conductors 132a and 132e. Also, it can be said that the conductor 132b is electrically connected to the transmission terminal Tx via the conductors 134b and 136b, the conductor 132c is electrically connected to the antenna terminal ANT via the conductors 134c and 136c, and the conductor 132d is electrically connected to the reception terminal Rx via the conductors 134d and 136d.

[0187] For the conductors 136a to 136e, a metal film containing an element selected from molybdenum, titanium, tantalum, tungsten, aluminum, copper, chromium, neodymium, and scandium, or a metal nitride film (tantalum nitride film, titanium nitride film, molybdenum nitride film, tungsten nitride film) containing the above-described elements as components can be used. Alternatively, a conductive material such as indium tin oxide, indium oxide containing tungsten oxide, indium zinc oxide containing tungsten oxide, indium oxide containing titanium oxide, indium tin oxide containing titanium oxide, indium zinc oxide, or indium tin oxide added with silicon oxide can also be applied.

[0188] In this embodiment, the conductors 136a to 136e are shown in a single-layer configuration, but the configuration is not limited thereto, and a stacked configuration of two or more layers may be used. For example, a conductor having barrier properties, and a conductor having high conductivity may be formed between a conductor having barrier properties and a conductor having high conductivity, and a conductor having high adhesion to the conductor having high conductivity.

[0189] An insulator 126 is provided on the insulator 124 and on the conductors 136a to 136e. As the insulator 126, for example, silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, aluminum oxide, aluminum oxynitride, aluminum nitride oxide, aluminum nitride, or the like may be used. Further, the insulator 126 may function as a planarization film that covers the uneven shape below it.

[0190] Next, the functions of the conductor 130 and the like will be described. The conductor 130 is provided so as to have a region overlapping with the conductor 132b, the conductor 132c, and the conductor 132d.

[0191] By providing the conductor 130 so as to have a region overlapping with the conductor 132b, the conductor 132c, and the conductor 132d, etc., as shown in FIG. 7B1, the insulators 106, 108, 110, 112, 114, and 116 are used as dielectrics, and a capacitor 140 having a configuration in which the dielectrics are sandwiched between the conductor 130 and the conductor 132 is formed. Here, one terminal of the AC power supply 142 shown in FIG. 7B1 is electrically connected to the conductor 132. Further, as described above, the potential of the conductor 130 can be set to a reference potential such as a ground potential. Therefore, it can be said that the other terminal of the AC power supply 142 is electrically connected to the conductor 130. Note that FIG. 7B2 is a circuit diagram in which the capacitor 140 is replaced with a circuit symbol.

[0192] The AC power supply 142 can be an AC power supply having a function of generating, for example, a signal 30 which is a signal transmitted by the wireless transceiver 10 to the outside of the wireless transceiver 10 when the conductor 132 is the conductor 132b. Further, when the conductor 132 is the conductor 132c, it can be an AC power supply having a function of generating, for example, a signal 40 which is a signal received by the wireless transceiver 10 from the outside of the wireless transceiver 10. Further, when the conductor 132 is the conductor 132d, it can be an AC power supply having a function of transmitting the signal 40 to a device electrically connected to the reception terminal Rx, for example.

[0193] Note that the conductor 132 and one terminal of the AC power supply 142 do not necessarily have to be physically connected by wiring or the like. Further, the conductor 130 and the other terminal of the AC power supply 142 do not necessarily have to be physically connected by wiring or the like. For example, signals generated by the AC power supply 142 are transmitted by radio waves. Therefore, even if the conductor 132 and the AC power supply 142 are not physically connected, it can be said that the conductor 132 and the AC power supply 142 are electrically connected.

[0194] Next, consider the case where the coupler 20 does not have the conductor 130. Note that it also does not have the insulator 102 and the insulator 104. In this case, as shown in FIG. 7B3, a capacitor 144 is formed with the insulators 106, 108, 110, 112, 114, and 116 as dielectrics and the dielectrics sandwiched between the substrate 100 and the conductor 132.

[0195] FIG. 7B4 is a circuit diagram in which the capacitor 144 is replaced with a circuit symbol. If the substrate 100 is, for example, a silicon substrate or a semiconductor substrate, the electrical resistance of the substrate 100 is greater than the electrical resistance of the conductor 130. Therefore, the capacitor 144 can be considered to have a configuration in which a resistor 141 is electrically connected in series with the capacitor 140a. Here, the resistor 141 can represent the difference between the electrical resistance of the substrate 100 shown in FIG. 7B3 and the electrical resistance of the conductor 130 shown in FIG. 7B1.

[0196] As described above, when the sharing device 20 has the conductor 130, fluctuations in the potential generated by the AC power supply 142 due to electrical resistance can be suppressed more effectively than when the sharing device 20 does not have the conductor 130. Therefore, signals can be transmitted and received accurately by the wireless transceiver 10.

[0197] The transistor 200A shown in FIGS. 9A, 9B, and 9C is a modified example of the transistor 200 having the configuration shown in FIGS. 8A and 8B. FIG. 9A is a top view of the transistor 200A, FIG. 9B is a cross-sectional view of the transistor 200A in the channel length direction, and FIG. 9C is a cross-sectional view of the transistor 200A in the channel width direction. Note that, in the top view of FIG. 9A, the description of some elements is omitted for clarity of the figure.

[0198] The transistor 200A having the configuration shown in FIGS. 9A, 9B, and 9C is different from the transistor 200 having the configuration shown in FIGS. 8A and 8B in that it has the insulators 252, 213, and 204. Also, it is different from the transistor 200 having the configuration shown in FIGS. 8A and 8B in that the insulator 252 is provided in contact with the side surface of the conductor 134. Furthermore, it is different from the transistor 200 having the configuration shown in FIGS. 8A and 8B in that it does not have the insulator 112.

[0199] In the transistor 200A having the configuration shown in FIGS. 9A, 9B, and 9C, the insulator 213 is provided on the insulator 106. Also, the insulator 204 is provided on the insulator 122 and on the insulator 213.

[0200] In the transistor 200A configured as shown in FIGS. 9A, 9B, and 9C, insulators 108, 110, 114, 116, 118, 120, and 122 are patterned, and an insulator 204 is configured to cover them. That is, the insulator 204 is in contact with the upper surface of the insulator 122, the side surface of the insulator 122, the side surface of the insulator 120, the side surface of the insulator 118, the side surface of the insulator 116, the side surface of the insulator 114, the side surface of the insulator 110, the side surface of the insulator 108, and the upper surface of the insulator 213, respectively. Thereby, the metal oxide 230 and the like are isolated from the outside by the insulator 204 and the insulator 213.

[0201] The insulator 213 and the insulator 204 preferably have a high function of suppressing the diffusion of hydrogen (for example, at least one of a hydrogen atom, a hydrogen molecule, etc.) or water molecules. For example, it is preferable to use silicon nitride or silicon oxynitride, which are materials having a high hydrogen barrier property, as the insulator 213 and the insulator 204. Thereby, since the diffusion of hydrogen or the like into the metal oxide 230 can be suppressed, the deterioration of the characteristics of the transistor 200A can be suppressed. Therefore, the reliability of the communication device according to one aspect of the present invention can be enhanced.

[0202] The insulator 252 is provided in contact with the insulator 124, the insulator 204, the insulator 122, the insulator 120, and the insulator 118. The insulator 252 preferably has a function of suppressing the diffusion of hydrogen or water molecules. For example, as the insulator 252, it is preferable to use an insulator such as silicon nitride, aluminum oxide, or silicon oxynitride, which is a material having a high hydrogen barrier property. In particular, since silicon nitride is a material having a high hydrogen barrier property, it is suitable for use as the insulator 252. By using a material having a high hydrogen barrier property as the insulator 252, the diffusion of impurities such as water or hydrogen from the insulator 120 or the like through the conductor 134 into the metal oxide 230 can be suppressed. In addition, the absorption of oxygen contained in the insulator 120 by the conductor 134 can be suppressed. As described above, the reliability of the communication device according to one aspect of the present invention can be enhanced.

[0203] Using FIGS. 10A, 10B, and 10C, a configuration example of the transistor 200B will be described. FIG. 10A is a top view of the transistor 200B. FIG. 10B is a cross-sectional view of the L1-L2 portion indicated by the dashed line in FIG. 10A. FIG. 10C is a cross-sectional view of the W1-W2 portion indicated by the dashed line in FIG. 10A. In the top view of FIG. 10A, the description of some elements is omitted for clarity of the figure.

[0204] The transistor 200B is a modified example of the transistor 200 and is a transistor that can be replaced with the transistor 200. Therefore, in order to prevent repetition of the description, mainly the differences between the transistor 200B and the transistor 200 will be described.

[0205] The conductor 138 that functions as the first gate has the conductor 138a and the conductor 138b on the conductor 138a. It is preferable to use a conductive material for the conductor 138a that has a function of suppressing the diffusion of impurities such as hydrogen atoms, hydrogen molecules, water molecules, and copper atoms. Alternatively, it is preferable to use a conductive material that has a function of suppressing the diffusion of oxygen (for example, at least one of oxygen atoms and oxygen molecules).

[0206] Since the conductor 138a has a function of suppressing the diffusion of oxygen, the material selectivity of the conductor 138b can be improved. That is, by having the conductor 138a, oxidation of the conductor 138b can be suppressed, and a decrease in conductivity can be suppressed.

[0207] In addition, it is preferable to provide the insulator 118 so as to cover the upper surface and the side surface of the conductor 138 and the side surface of the insulator 245. The insulator 118 may be made of an insulating material having a function of suppressing the diffusion of impurities such as water or hydrogen and oxygen. For example, it is preferable to use aluminum oxide or hafnium oxide. In addition, for example, metal oxides such as magnesium oxide, gallium oxide, germanium oxide, yttrium oxide, zirconium oxide, lanthanum oxide, neodymium oxide, or tantalum oxide, silicon oxynitride, or silicon nitride can also be used.

[0208] By providing the insulator 118, oxidation of the conductor 138 can be suppressed. Further, by having the insulator 118, diffusion of impurities such as water and hydrogen contained in the insulator 120 into the transistor 200B can be suppressed.

[0209] In the transistor 200B, since the conductor 138 overlaps a part of the conductor 132, the parasitic capacitance is likely to be larger than that of the transistor 200. Therefore, the operating frequency tends to be lower than that of the transistor 200. However, since the process of providing an opening in the insulator 120 and embedding the conductor 138, the insulator 245, etc. is unnecessary, the productivity is high as compared with the transistor 200.

[0210] The configurations, structures, methods, etc. shown in this embodiment can be used in appropriate combination with the configurations, structures, methods, etc. shown in other embodiments.

[0211] (Embodiment 2) In this embodiment, an oxide semiconductor which is a kind of metal oxide will be described.

[0212] The metal oxide preferably contains at least indium or zinc. Particularly preferably, it contains indium and zinc. In addition to those, it is preferable that aluminum, gallium, yttrium, tin, etc. are contained. Further, one or more selected from boron, silicon, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, magnesium, cobalt, etc. may be contained.

[0213] <Classification of crystal structure> First, the classification of the crystal structure in the oxide semiconductor will be described with reference to FIG. 11A. FIG. 11A is a diagram for explaining the classification of the crystal structure of an oxide semiconductor, typically IGZO (a metal oxide containing In, Ga, and Zn).

[0214] As shown in FIG. 11A, oxide semiconductors are roughly classified into "Amorphous", "Crystalline", and "Crystal". Further, "Amorphous" includes completely amorphous. Also, "Crystalline" includes CAAC (c-axis-aligned crystalline), nc (nanocrystalline), and CAC (cloud-aligned composite). Note that single crystal, poly crystal, and completely amorphous are excluded from the classification of "Crystalline" (excluding single crystal and poly crystal). Also, "Crystal" includes single crystal and poly crystal.

[0215] Note that the structure within the thick frame shown in FIG. 11A is an intermediate state between "Amorphous" and "Crystal", and belongs to a new boundary region (New crystalline phase). That is, the structure can be rephrased as a structure that is energetically unstable "Amorphous" and is completely different from "Crystal".

[0216] Note that the crystal structure of a film or a substrate can be evaluated using an X-ray diffraction (XRD) spectrum. Here, FIG. 11B shows the XRD spectrum obtained by grazing-incidence XRD (GIXD) measurement of a CAAC-IGZO film classified as "Crystalline". Note that the GIXD method is also called the thin film method or the Seemann-Bohlin method. Hereinafter, the XRD spectrum obtained by the GIXD measurement shown in FIG. 11B will be simply referred to as the XRD spectrum. Note that the composition of the CAAC-IGZO film shown in FIG. 11B is in the vicinity of In:Ga:Zn = 4:2:3 [atomic ratio]. Also, the thickness of the CAAC-IGZO film shown in FIG. 11B is 500 nm.

[0217] As shown in FIG. 11B, in the XRD spectrum of the CAAC-IGZO film, peaks indicating distinct crystallinity are detected. Specifically, in the XRD spectrum of the CAAC-IGZO film, a peak indicating c-axis orientation is detected near 2θ = 31°. As shown in FIG. 11B, the peak near 2θ = 31° is asymmetric about the axis of the angle at which the peak intensity (Intensity) was detected.

[0218] Also, the crystal structure of the film or substrate can be evaluated by the diffraction pattern (also referred to as the nano beam electron diffraction pattern) observed by the nano beam electron diffraction method (NBED). The diffraction pattern of the CAAC-IGZO film is shown in FIG. 11C. FIG. 11C is a diffraction pattern observed by NBED in which the electron beam is incident parallel to the substrate. Note that the composition of the CAAC-IGZO film shown in FIG. 11C is near In:Ga:Zn = 4:2:3 [atomic ratio]. Also, in the nano beam electron diffraction method, electron diffraction is performed with a probe diameter of 1 nm.

[0219] As shown in FIG. 11C, in the diffraction pattern of the CAAC-IGZO film, a plurality of spots indicating c-axis orientation are observed.

[0220] <<Structure of Oxide Semiconductor>> Note that when focusing on the crystal structure, the oxide semiconductor may be classified differently from that in FIG. 11A. For example, the oxide semiconductor can be divided into a single crystal oxide semiconductor and other non-single crystal oxide semiconductors. Examples of the non-single crystal oxide semiconductor include the above-mentioned CAAC-OS and nc-OS. Also, the non-single crystal oxide semiconductor includes a polycrystalline oxide semiconductor, an amorphous-like oxide semiconductor (a-like OS), an amorphous oxide semiconductor, and the like.

[0221] Here, the details of the above-mentioned CAAC-OS, nc-OS, and a-like OS will be described.

[0222] [CAAC-OS] CAAC-OS is an oxide semiconductor having a plurality of crystal regions, and the plurality of crystal regions have their c-axes oriented in a specific direction. Here, the specific direction means the thickness direction of the CAAC-OS film, the normal direction of the surface on which the CAAC-OS film is formed, or the normal direction of the surface of the CAAC-OS film. Also, the crystal region is a region having periodicity in the atomic arrangement. When the atomic arrangement is regarded as a lattice arrangement, the crystal region is also a region where the lattice arrangements are aligned. Further, CAAC-OS has a region where a plurality of crystal regions are connected in the a-b plane direction, and this region may have strain. Here, the strain refers to a portion where the orientation of the lattice arrangement changes between a region where the lattice arrangements are aligned and another region where the lattice arrangements are aligned in the region where a plurality of crystal regions are connected. That is, CAAC-OS is an oxide semiconductor having its c-axis oriented and having no obvious orientation in the a-b plane direction.

[0223] Each of the plurality of crystal regions is composed of one or a plurality of minute crystals (crystals having a maximum diameter of less than 10 nm). When a crystal region is composed of one minute crystal, the maximum diameter of the crystal region is less than 10 nm. Also, when a crystal region is composed of a number of minute crystals, the size of the crystal region may be on the order of several tens of nm.

[0224] Also, in an In-M-Zn oxide (where the element M is one or more selected from aluminum, gallium, yttrium, tin, titanium, etc.), CAAC-OS tends to have a layered crystal structure (also referred to as a layered structure) in which a layer containing indium (In) and oxygen (hereinafter referred to as the In layer) and a layer containing the element M, zinc (Zn), and oxygen (hereinafter referred to as the (M,Zn) layer) are laminated. Here, indium and the element M are mutually substitutable. Therefore, the (M,Zn) layer may contain indium. Also, the In layer may contain the element M. Note that the In layer may also contain Zn. The layered structure is observed as a lattice image, for example, in a high-resolution TEM image.

[0225] When performing structural analysis on the CAAC-OS film using, for example, an XRD apparatus, in the out-of-plane XRD measurement using θ / 2θ scan, a peak indicating c-axis orientation is detected at 2θ = 31° or in its vicinity. Note that the position of the peak indicating c-axis orientation (the value of 2θ) may vary depending on the type and composition of the metal elements constituting CAAC-OS.

[0226] Also, for example, in the electron diffraction pattern of the CAAC-OS film, a plurality of bright spots (spots) are observed. Note that one spot and another spot are observed at point-symmetric positions with the spot of the incident electron beam transmitted through the sample (also referred to as the direct spot) as the center of symmetry.

[0227] When observing the crystal region from the above specific direction, the lattice arrangement within the crystal region is based on a hexagonal lattice, but the unit cell is not necessarily a regular hexagon and may be a non-regular hexagon. Also, in the above distortion, there may be lattice arrangements such as pentagons and heptagons. Note that in CAAC-OS, even near the distortion, no distinct crystal grain boundaries can be confirmed. That is, it can be seen that the formation of crystal grain boundaries is suppressed by the distortion of the lattice arrangement. This is presumably because CAAC-OS can tolerate distortion due to the fact that the arrangement of oxygen atoms is not dense in the a-b plane direction and the interatomic bond distance changes due to the substitution of metal atoms.

[0228] Note that a crystal structure in which distinct crystal grain boundaries are confirmed is called a so-called polycrystal. Crystal grain boundaries can become recombination centers, and there is a high possibility of causing a decrease in the on-current of the transistor and a decrease in the field-effect mobility due to the capture of carriers. Therefore, CAAC-OS in which no distinct crystal grain boundaries are confirmed is one of the crystalline oxides having a crystal structure suitable for the semiconductor of the transistor. Note that for forming CAAC-OS, a configuration having Zn is preferable. For example, In-Zn oxide and In-Ga-Zn oxide are preferable because they can suppress the generation of crystal grain boundaries more than In oxide.

[0229] CAAC-OS is an oxide semiconductor with high crystallinity and no distinct crystal grain boundaries. Therefore, it can be said that CAAC-OS is less likely to have a reduction in electron mobility due to crystal grain boundaries. Also, since the crystallinity of an oxide semiconductor may decrease due to the incorporation of impurities or the generation of defects, etc., CAAC-OS can also be said to be an oxide semiconductor with few impurities and defects (such as oxygen deficiencies). Therefore, the physical properties of the oxide semiconductor having CAAC-OS are stable. For this reason, the oxide semiconductor having CAAC-OS is heat-resistant and highly reliable. Also, CAAC-OS is stable against high temperatures (so-called thermal budget) in the manufacturing process. Therefore, when CAAC-OS is used for an OS transistor, it becomes possible to expand the degree of freedom in the manufacturing process.

[0230] [nc-OS] nc-OS has periodicity in the atomic arrangement in a minute region (for example, a region of 1 nm or more and 10 nm or less, particularly a region of 1 nm or more and 3 nm or less). In other words, nc-OS has minute crystals. Since the size of the minute crystals is, for example, 1 nm or more and 10 nm or less, particularly 1 nm or more and 3 nm or less, the minute crystals are also called nano-crystals. Also, nc-OS does not show regularity in the crystal orientation between different nano-crystals. Therefore, no orientation is seen in the entire film. Therefore, depending on the analysis method, nc-OS may not be distinguishable from a-like OS or an amorphous oxide semiconductor. For example, when structural analysis is performed on an nc-OS film using an XRD apparatus, no peak indicating crystallinity is detected in the Out-of-plane XRD measurement using θ / 2θ scan. Also, when electron beam diffraction (also called limited field electron beam diffraction) using an electron beam with a probe diameter larger than the nano-crystals (for example, 50 nm or more) is performed on an nc-OS film, a diffraction pattern like a halo pattern is observed. On the other hand, when electron beam diffraction (also called nano-beam electron beam diffraction) using an electron beam with a probe diameter close to or smaller than the nano-crystals (for example, 1 nm or more and 30 nm or less) is performed on an nc-OS film, an electron beam diffraction pattern in which a plurality of spots are observed within a ring-shaped region centered on a direct spot may be obtained.

[0231] [a-like OS] The a-like OS is an oxide semiconductor having a structure between the nc-OS and the amorphous oxide semiconductor. The a-like OS has a loose or low-density region. That is, the a-like OS has lower crystallinity compared to the nc-OS and the CAAC-OS. Also, the a-like OS has a higher hydrogen concentration in the film compared to the nc-OS and the CAAC-OS.

[0232] [[Constitution of Oxide Semiconductor]] Next, the details of the above-mentioned CAC-OS will be described. Note that the CAC-OS relates to the material constitution.

[0233] [CAC-OS] The CAC-OS is, for example, a configuration of a material in which the elements constituting the metal oxide are unevenly distributed in a size of 0.5 nm or more and 10 nm or less, preferably 1 nm or more and 3 nm or less, or in the vicinity thereof. In the following, in the metal oxide, one or more metal elements are unevenly distributed, and a region having the metal element is in a state of being mixed in a size of 0.5 nm or more and 10 nm or less, preferably 1 nm or more and 3 nm or less, or in the vicinity thereof, which is also referred to as a mosaic state or a patch state.

[0234] Furthermore, the CAC-OS is in a mosaic state by separating the material into a first region and a second region, and the first region is a configuration distributed in the film (hereinafter also referred to as a cloud state). That is, the CAC-OS is a composite metal oxide having a configuration in which the first region and the second region are mixed.

[0235] Here, the atomic ratios of In, Ga, and Zn to the metal elements constituting the CAC-OS in In-Ga-Zn oxide are denoted as [In], [Ga], and [Zn], respectively. For example, in the CAC-OS of In-Ga-Zn oxide, the first region is a region where [In] is larger than [In] in the composition of the CAC-OS film. Also, the second region is a region where [Ga] is larger than [Ga] in the composition of the CAC-OS film. Or, for example, the first region is a region where [In] is larger than [In] in the second region and [Ga] is smaller than [Ga] in the second region. Also, the second region is a region where [Ga] is larger than [Ga] in the first region and [In] is smaller than [In] in the first region.

[0236] Specifically, the above-mentioned first region is a region mainly composed of indium oxide, indium zinc oxide, etc. Also, the above-mentioned second region is a region mainly composed of gallium oxide, gallium zinc oxide, etc. That is, the above-mentioned first region can be rephrased as a region mainly composed of In. Also, the above-mentioned second region can be rephrased as a region mainly composed of Ga.

[0237] Note that there may be cases where no clear boundary can be observed between the above-mentioned first region and the above-mentioned second region.

[0238] For example, in the CAC-OS of In-Ga-Zn oxide, it can be confirmed by EDX mapping obtained using energy dispersive X-ray spectroscopy (EDX) that the region mainly composed of In (the first region) and the region mainly composed of Ga (the second region) are unevenly distributed and have a mixed structure.

[0239] When using CAC-OS in a transistor, the conductivity resulting from the first region and the insulating property resulting from the second region act complementarily, enabling the function of switching (turning on / off) to be imparted to the CAC-OS. That is, CAC-OS has a conductive function in a part of the material and an insulating function in a part of the material, and has a semiconductor function as a whole. By separating the conductive function and the insulating function, both functions can be enhanced to the maximum extent. Therefore, by using CAC-OS in a transistor, a high on-current (I on ), a high field-effect mobility (μ), and a good switching operation can be realized.

[0240] Oxide semiconductors have various structures, each having different characteristics. The oxide semiconductor according to one aspect of the present invention may have two or more of an amorphous oxide semiconductor, a polycrystalline oxide semiconductor, an a-like OS, a CAC-OS, an nc-OS, and a CAAC-OS.

[0241] <Transistor having an oxide semiconductor> Subsequently, the case of using the above oxide semiconductor in a transistor will be described.

[0242] By using the above oxide semiconductor in a transistor, a transistor with a high field-effect mobility can be realized. Also, a highly reliable transistor can be realized.

[0243] For a transistor, it is preferable to use an oxide semiconductor with a low carrier concentration. For example, the carrier concentration of the oxide semiconductor is 1×10 17 cm -3 or less, preferably 1×10 15 cm -3 or less, more preferably 1×10 13 cm -3 or less, even more preferably 1×10 11 cm -3 or less, still more preferably 1×10 10 cm -3 less, and 1×10 -9 cm-3 The above is the case. When reducing the carrier concentration of the oxide semiconductor film, the impurity concentration in the oxide semiconductor film may be decreased and the density of defect levels may be decreased. In this specification and the like, a low impurity concentration and a low density of defect levels are referred to as high-purity intrinsic or substantially high-purity intrinsic. Note that an oxide semiconductor with a low carrier concentration may be referred to as a high-purity intrinsic or substantially high-purity intrinsic oxide semiconductor.

[0244] In addition, since an oxide semiconductor film that is high-purity intrinsic or substantially high-purity intrinsic has a low density of defect levels, the density of trap levels may also be low.

[0245] In addition, the charge trapped in the trap levels of the oxide semiconductor takes a long time to disappear and may behave as if it were a fixed charge. Therefore, a transistor in which a channel formation region is formed in an oxide semiconductor with a high density of trap levels may have unstable electrical characteristics.

[0246] Therefore, in order to stabilize the electrical characteristics of the transistor, it is effective to reduce the impurity concentration in the oxide semiconductor. In addition, in order to reduce the impurity concentration in the oxide semiconductor, it is preferable to also reduce the impurity concentration in the adjacent film. Examples of the impurity include hydrogen, nitrogen, an alkali metal, an alkaline earth metal, iron, nickel, and silicon.

[0247] <Impurity> Here, the influence of each impurity in the oxide semiconductor will be described.

[0248] In an oxide semiconductor, when silicon or carbon, which is one of the Group 14 elements, is contained, defect levels are formed in the oxide semiconductor. For this reason, the concentration of silicon or carbon in the oxide semiconductor and the concentration of silicon or carbon near the interface with the oxide semiconductor (the concentration obtained by secondary ion mass spectrometry (SIMS)) are 2×10 18 atoms / cm 3 or less, preferably 2×10 17atoms / cm 3 Shall be as follows.

[0249] In addition, when an alkali metal or an alkaline earth metal is contained in the oxide semiconductor, defect levels may be formed and carriers may be generated. Therefore, a transistor using an oxide semiconductor containing an alkali metal or an alkaline earth metal tends to have normally-on characteristics. For this reason, the concentration of the alkali metal or alkaline earth metal in the oxide semiconductor obtained by SIMS is set to 1×10 18 atoms / cm 3 or less, preferably 2×10 16 atoms / cm 3 or less.

[0250] In addition, in the oxide semiconductor, when nitrogen is contained, electrons as carriers are generated, the carrier concentration increases, and it tends to be n-type. As a result, a transistor using an oxide semiconductor containing nitrogen as the semiconductor tends to have normally-on characteristics. Or, in the oxide semiconductor, when nitrogen is contained, trap levels may be formed. As a result, the electrical characteristics of the transistor may become unstable. For this reason, the nitrogen concentration in the oxide semiconductor obtained by SIMS is set to less than 5×10 19 atoms / cm 3 preferably less than 5×10 18 atoms / cm 3 more preferably 1×10 18 atoms / cm 3 or less, even more preferably 5×10 17 atoms / cm 3 or less.

[0251] In addition, since hydrogen contained in the oxide semiconductor reacts with oxygen bonded to metal atoms to form water, oxygen vacancies may be formed. When hydrogen enters these oxygen vacancies, electrons, which are carriers, may be generated. Also, a part of the hydrogen may bond with oxygen bonded to metal atoms to generate electrons, which are carriers. Therefore, a transistor using an oxide semiconductor containing hydrogen tends to have normally-on characteristics. For this reason, it is preferable that the hydrogen in the oxide semiconductor is reduced as much as possible. Specifically, in the oxide semiconductor, the hydrogen concentration obtained by SIMS is less than 1×10 20 atoms / cm 3 , preferably less than 1×10 19 atoms / cm 3 , more preferably less than 5×10 18 atoms / cm 3 , still more preferably less than 1×10 18 atoms / cm 3 .

[0252] By using an oxide semiconductor with sufficiently reduced impurities in the channel formation region of a transistor, stable electrical characteristics can be imparted.

[0253] The configurations, structures, methods, etc. shown in this embodiment can be used in appropriate combination with those shown in other embodiments.

[0254] (Embodiment 3) In this embodiment, application examples of the communication device described above will be described.

[0255] [Semiconductor Wafer, Chip] FIG. 12A shows a top view of a substrate 711 before dicing processing. As the substrate 711, for example, a semiconductor substrate (also referred to as a "semiconductor wafer") can be used. A plurality of circuit regions 712 are provided on the substrate 711. In the circuit region 712, a communication device according to one aspect of the present invention, a CPU, an RF tag, an image sensor, or the like can be provided.

[0256] The plurality of circuit regions 712 are each surrounded by a separation region 713. A separation line (also referred to as a "dicing line") 714 is set at a position overlapping the separation region 713. By cutting the substrate 711 along the separation line 714, the chip 715 including the circuit region 712 can be cut out from the substrate 711. An enlarged view of the chip 715 is shown in Fig. 12B.

[0257] In addition, a conductor or a semiconductor may be provided in the separation region 713. By providing a conductor or a semiconductor in the separation region 713, ESD that may occur during the dicing process can be alleviated, and a decrease in the yield of the dicing process can be suppressed. In general, the dicing process is performed while flowing pure water with a reduced specific resistance by dissolving carbon dioxide gas or the like to the cutting part for the purpose of cooling the substrate, removing chips, preventing charging, and the like. By providing a conductor or a semiconductor in the separation region 713, the amount of use of the pure water can be reduced. Therefore, the production cost of the communication device can be reduced. In addition, the productivity of the communication device can be improved.

[0258] As the semiconductor provided in the separation region 713, it is preferable to use a material having a band gap of 2.5 eV or more and 4.2 eV or less, preferably 2.7 eV or more and 3.5 eV or less. When such a material is used, the accumulated charges can be slowly discharged, so that a rapid movement of charges due to ESD can be suppressed, and electrostatic breakdown can be made less likely to occur.

[0259] 〔Electronic Component〕 An example of applying the chip 715 to an electronic component will be described with reference to Figs. 13A and 13B. Note that an electronic component is also referred to as a semiconductor package or an IC package. There are a plurality of standards and names for electronic components depending on the terminal extraction direction and the shape of the terminals.

[0260] In the assembly process (post-process), the electronic component is completed by combining the communication device shown in the above embodiment and components other than the communication device.

[0261] The subsequent processes will be described using the flowchart shown in FIG. 13A. After the element substrate having the communication device shown in the above embodiment is completed in the previous process, a "back grinding process" is performed to grind the back surface (the surface on which no communication device or the like is formed) of the element substrate (step S721). By thinning the element substrate by grinding, warping of the element substrate can be reduced, and miniaturization of the electronic components can be achieved.

[0262] Next, a "dicing process" is performed to separate the element substrate into a plurality of chips (chip 715) (step S722). Then, a "die bonding process" is performed to individually pick up the separated chips and bond them onto the lead frame (step S723). For the bonding between the chip and the lead frame in the die bonding process, an appropriate method suitable for the product, such as bonding with resin or bonding with tape, is selected. Note that the chip may be bonded onto an interposer substrate instead of the lead frame.

[0263] Next, a "wire bonding process" is performed to electrically connect the leads of the lead frame and the electrodes on the chip with a thin metal wire (wire) (step S724). As the thin metal wire, a silver wire or a gold wire can be used. Also, for wire bonding, ball bonding or wedge bonding can be used.

[0264] The wire-bonded chip is subjected to a "sealing process (molding process)" using an epoxy resin or the like (step S725). By performing the sealing process, the inside of the electronic component is filled with resin, and the circuit portion built in the chip and the wire connecting the chip and the lead can be protected from mechanical external forces, and deterioration of characteristics (reduction in reliability) due to moisture and dust can be reduced.

[0265] Next, a "lead plating process" for plating the leads of the lead frame is performed (step S726). The plating process suppresses rusting of the leads and enables more reliable soldering when mounting on a printed circuit board later. Next, a "forming process" for cutting and forming the leads is performed (step S727).

[0266] Next, a "marking process" for performing printing processing (marking) on the surface of the package is performed (step S728). Then, through an "inspection process" (step S729) for examining the quality of the external shape, presence or absence of malfunction, etc., the electronic component is completed.

[0267] Also, a perspective schematic diagram of the completed electronic component is shown in FIG. 13B. In FIG. 13B, as an example of the electronic component, a perspective schematic diagram of a QFP (Quad Flat Package) is shown. The electronic component 750 shown in FIG. 13B shows leads 755 and a communication device 753. As the communication device 753, the communication devices shown in the above embodiments can be used.

[0268] The electronic component 750 shown in FIG. 13B is mounted on a printed circuit board 752, for example. A plurality of such electronic components 750 are combined, and each is electrically connected on the printed circuit board 752 to complete a board (mounted board 754) on which the electronic components are mounted. The completed mounted board 754 is used in electronic devices and the like.

[0269] 〔Electronic Device〕 Next, an example of an electronic device including the communication device or the above-described electronic component according to an aspect of the present invention will be described with reference to FIG. 14.

[0270] As an electronic device using the communication device or electronic component according to one aspect of the present invention, there are a display device such as a television or a monitor, a lighting device, a desktop or notebook personal computer, a word processor, an image playback device that plays back still images or moving images stored in a recording medium such as a DVD (Digital Versatile Disc), a portable CD player, a radio, a tape recorder, a headphone stereo, a stereo, a table clock, a wall clock, a cordless telephone handset, a transceiver, a mobile phone, a car phone, a portable game machine, a tablet terminal, a large game machine such as a pachinko machine, a calculator, a portable information terminal (also referred to as a "portable information device"), an electronic notebook, an e-book terminal, an electronic translator, a voice input device, a video camera, a digital still camera, a high-frequency heating device such as an electric shaver or a microwave oven, an electric rice cooker, an electric washing machine, an electric vacuum cleaner, a water heater, a fan, a hair dryer, air conditioning equipment such as an air conditioner, a humidifier, and a dehumidifier, a dish washer, a dish dryer, a clothes dryer, a futon dryer, an electric refrigerator, an electric freezer, an electric refrigerator-freezer, a freezer for DNA storage, a flashlight, tools such as a chain saw, a smoke detector, medical equipment such as a dialysis device, and the like. Further, there are industrial devices such as induction lamps, traffic lights, belt conveyors, elevators, escalators, industrial robots, power storage systems, and power storage devices for power leveling and smart grids.

[0271] In addition, a moving body propelled by an electric motor using the power from the power storage device is also to be included in the category of electronic devices. Examples of the moving body include an electric vehicle (EV), a hybrid vehicle (HEV) having both an internal combustion engine and an electric motor, a plug-in hybrid vehicle (PHEV), a track-laying vehicle obtained by changing the tires of these vehicles to an endless track, a motorized bicycle including an electric assist bicycle, a motorcycle, an electric wheelchair, a golf cart, a small or large ship, a submarine, a helicopter, an aircraft, a rocket, a satellite, a space exploration vehicle or a planetary exploration vehicle, a spaceship, and the like.

[0272] The communication device or electronic component according to one aspect of the present invention can be used in communication devices incorporated in these electronic devices. By applying the communication device or electronic component according to one aspect of the present invention to the electronic device, the electronic device can perform wireless communication in a high-frequency band. Therefore, the electronic device can be made to conform to, for example, the 5G communication standard.

[0273] The electronic device may have a sensor (including a function of measuring force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor or infrared rays), etc.

[0274] The electronic device can have various functions. For example, it can have functions such as displaying various information (still images, moving images, text images, etc.) on a display unit, a touch panel function, a function of displaying a calendar, date or time, a function of executing various software (programs), a wireless communication function, a function of reading programs or data recorded on a recording medium, etc.

[0275] FIG. 14 and FIGS. 15A to 15F show an example of an electronic device. In FIG. 14, the display device 8000 is an example of an electronic device using the communication device 8004 according to one aspect of the present invention. Specifically, the display device 8000 corresponds to a display device for receiving TV broadcasts, and has a housing 8001, a display unit 8002, a speaker unit 8003, a communication device 8004, a power storage device 8005, etc. The communication device 8004 according to one aspect of the present invention is provided inside the housing 8001. The communication device 8004 can hold control information, control programs, etc. Further, the communication device 8004 has a communication function and can make the display device 8000 function as an IoT device. Also, the display device 8000 can receive power supply from a commercial power source and can also use the power stored in the power storage device 8005.

[0276] The display unit 8002 can use a display device such as a liquid crystal display device, a light-emitting display device having a light-emitting element such as an organic EL element in each pixel, an electrophoretic display device, a DMD (Digital Micromirror Device), a PDP (Plasma Display Panel), an FED (Field Emission Display).

[0277] Note that the display device includes all information display devices such as those for TV broadcast reception, personal computers, and advertising displays.

[0278] In FIG. 14, the installed lighting device 8100 is an example of an electronic device using the communication device 8103 of one aspect of the present invention. Specifically, the lighting device 8100 includes a housing 8101, a light source 8102, a communication device 8103, a power storage device 8105, etc. In FIG. 14, the case where the communication device 8103 is provided inside the ceiling 8104 where the housing 8101 and the light source 8102 are installed is illustrated, but the communication device 8103 may be provided inside the housing 8101. The communication device 8103 can hold information such as the emission luminance of the light source 8102 and a control program. Further, the communication device 8103 has a communication function and can make the lighting device 8100 function as an IoT device. Also, the lighting device 8100 can receive power supply from a commercial power source or use the power stored in the power storage device.

[0279] Note that in FIG. 14, the installed lighting device 8100 provided on the ceiling 8104 is illustrated, but the communication device of one aspect of the present invention can also be used for installed lighting devices provided on, for example, side walls 8405, floors 8406, windows 8407, etc. other than the ceiling 8104, or for desktop lighting devices.

[0280] Also, as the light source 8102, an artificial light source that artificially obtains light using power can be used. Specifically, an incandescent bulb, a discharge lamp such as a fluorescent lamp, and a light-emitting element such as an LED or an organic EL element can be cited as an example of the above artificial light source.

[0281] In FIG. 14, an air conditioner having an indoor unit 8200 and an outdoor unit 8204 is an example of an electronic device using a communication device 8203 according to one aspect of the present invention. Specifically, the indoor unit 8200 includes a housing 8201, an air outlet 8202, a communication device 8203, a power storage device 8205, and the like. In FIG. 14, the case where the communication device 8203 is provided in the indoor unit 8200 is illustrated, but the communication device 8203 may be provided in the outdoor unit 8204. Alternatively, the communication device 8203 may be provided in both the indoor unit 8200 and the outdoor unit 8204. The communication device 8203 can hold control information of the air conditioner, a control program, and the like. Further, the communication device 8203 has a communication function and can make the air conditioner function as an IoT device. Further, the air conditioner can receive power supply from a commercial power source or use the power stored in the power storage device 8205.

[0282] Note that in FIG. 14, a separate type air conditioner composed of an indoor unit and an outdoor unit is illustrated, but a communication device according to one aspect of the present invention can also be used for an integrated type air conditioner having the functions of the indoor unit and the outdoor unit in one housing.

[0283] In FIG. 14, an electric refrigerator-freezer 8300 is an example of an electronic device using a communication device 8304 according to one aspect of the present invention. Specifically, the electric refrigerator-freezer 8300 includes a housing 8301, a refrigerator door 8302, a freezer door 8303, a communication device 8304, a power storage device 8305, and the like. In FIG. 14, the power storage device 8305 is provided inside the housing 8301. The communication device 8304 can hold control information of the electric refrigerator-freezer 8300, a control program, and the like. Further, the communication device 8304 has a communication function and can make the electric refrigerator-freezer 8300 function as an IoT device. Further, the electric refrigerator-freezer 8300 can receive power supply from a commercial power source or use the power stored in the power storage device 8305.

[0284] Fig. 15A shows an example of a wristwatch-type portable information terminal. The portable information terminal 6100 includes a housing 6101, a display unit 6102, a band 6103, operation buttons 6105, etc. Further, the portable information terminal 6100 includes a secondary battery and a communication device or electronic component according to an aspect of the present invention inside thereof. By using the communication device or electronic component according to an aspect of the present invention in the portable information terminal 6100, the portable information terminal 6100 can function as an IoT device.

[0285] Fig. 15B shows an example of a mobile phone. The portable information terminal 6200 includes, in addition to a display unit 6202 incorporated in a housing 6201, operation buttons 6203, a speaker 6204, a microphone 6205, etc.

[0286] Further, the portable information terminal 6200 includes a fingerprint sensor 6209 in a region overlapping with the display unit 6202. The fingerprint sensor 6209 may be an organic optical sensor. Since fingerprints vary from person to person, a fingerprint pattern can be acquired by the fingerprint sensor 6209 for personal authentication. The light emitted from the display unit 6202 can be used as a light source for acquiring a fingerprint pattern by the fingerprint sensor 6209.

[0287] Also, the portable information terminal 6200 includes a secondary battery and a communication device or electronic component according to an aspect of the present invention inside thereof. By using the communication device or electronic component according to an aspect of the present invention in the portable information terminal 6200, the portable information terminal 6200 can function as an IoT device.

[0288] Fig. 15C shows an example of a cleaning robot. The cleaning robot 6300 has a display unit 6302 arranged on the upper surface of a housing 6301, a plurality of cameras 6303 arranged on the side surface, a brush 6304, operation buttons 6305, various sensors, etc. Although not shown, the cleaning robot 6300 is provided with tires, a suction port, etc. The cleaning robot 6300 can move automatically, detect dust 6310, and suck the dust from a suction port provided on the lower surface.

[0289] For example, the cleaning robot 6300 can analyze the images captured by the camera 6303 and determine the presence or absence of obstacles such as walls, furniture, or steps. Also, when an object that is likely to get caught in the brush 6304, such as wiring, is detected by image analysis, the rotation of the brush 6304 can be stopped. The cleaning robot 6300 includes a secondary battery and a communication device or electronic component according to an aspect of the present invention inside thereof. By using the communication device or electronic component according to an aspect of the present invention in the cleaning robot 6300, the cleaning robot 6300 can be made to function as an IoT device.

[0290] FIG. 15D shows an example of a robot. The robot 6400 shown in FIG. 15D includes an arithmetic unit 6409, an illuminance sensor 6401, a microphone 6402, an upper camera 6403, a speaker 6404, a display unit 6405, a lower camera 6406, an obstacle sensor 6407, and a moving mechanism 6408.

[0291] The microphone 6402 has a function of detecting the user's voice and environmental sounds, etc. Also, the speaker 6404 has a function of emitting sound. The robot 6400 can communicate with the user by using the microphone 6402 and the speaker 6404.

[0292] The display unit 6405 has a function of displaying various information. The robot 6400 can display the information desired by the user on the display unit 6405. The display unit 6405 may be equipped with a touch panel. Also, the display unit 6405 may be a removable information terminal, and by installing it at a fixed position of the robot 6400, charging and data transfer can be enabled.

[0293] The upper camera 6403 and the lower camera 6406 have the function of imaging the surroundings of the robot 6400. Also, the obstacle sensor 6407 can detect the presence or absence of obstacles in the traveling direction when the robot 6400 moves forward using the moving mechanism 6408. The robot 6400 can recognize the surrounding environment and move safely using the upper camera 6403, the lower camera 6406, and the obstacle sensor 6407.

[0294] The robot 6400 is equipped with a secondary battery and a communication device or electronic component according to one aspect of the present invention inside thereof. By using the communication device or electronic component according to one aspect of the present invention in the robot 6400, the robot 6400 can be made to function as an IoT device.

[0295] Figure 15E shows an example of an aircraft. The aircraft 6500 shown in Figure 15E has a propeller 6501, a camera 6502, a battery 6503, and electronic components 6504, etc., and has the function of autonomous flight.

[0296] For example, the image data captured by the camera 6502 is stored in the electronic component 6504. The electronic component 6504 can analyze the image data and detect the presence or absence of obstacles when moving. Also, the remaining battery level can be estimated by the electronic component 6504 from the change in the power storage capacity of the battery 6503. The aircraft 6500 is equipped with a communication device or electronic component according to one aspect of the present invention inside thereof. By using the communication device or electronic component according to one aspect of the present invention in the aircraft 6500, the aircraft 6500 can be made to function as an IoT device.

[0297] Figure 15F shows an example of an automobile. The automobile 7160 has an engine, tires, brakes, a steering device, a camera, etc. The automobile 7160 is equipped with a communication device or electronic component according to one aspect of the present invention inside thereof. By using the communication device or electronic component according to one aspect of the present invention in the automobile 7160, the automobile 7160 can be made to function as an IoT device.

[0298] The configurations, structures, methods, etc. shown in this embodiment can be used in appropriate combination with those shown in other embodiments.

[0299] (Embodiment 4) Using the OS transistor shown in this specification or the like, a normally-off CPU (also referred to as a "Noff-CPU") can be realized. Note that a Noff-CPU is an integrated circuit including a normally-off type transistor that is in a non-conducting state (also referred to as an off state) even when the gate voltage is 0V.

[0300] The Noff-CPU can stop the power supply to circuits that are not required to operate within the Noff-CPU and put the circuits in a standby state. In the circuits where the power supply is stopped and the standby state is entered, no power is consumed. Therefore, the Noff-CPU can minimize the power consumption. In addition, the Noff-CPU can retain information necessary for operations such as set conditions for a long period even when the power supply is stopped. To resume from the standby state, it is only necessary to resume the power supply to the circuit, and rewriting of set conditions and the like is not required. That is, a high-speed resume from the standby state is possible. Thus, the Noff-CPU can reduce the power consumption without significantly reducing the operating speed.

[0301] The Noff-CPU can be suitably used, for example, in small-scale systems such as IoT (Internet of Things) end devices (also referred to as "endpoint microcontrollers") 803 in the IoT field.

[0302] Fig. 16 shows the hierarchical structure of the IoT network and the trends of the required specifications. In Fig. 16, the power consumption 804 and the processing performance 805 are shown as the required specifications. The hierarchical structure of the IoT network is roughly divided into an upper-layer cloud field 801 and a lower-layer embedded field 802. The cloud field 801 includes, for example, servers. The embedded field 802 includes, for example, machines, industrial robots, in-vehicle devices, home appliances, and the like.

[0303] Higher up in the hierarchy, higher processing performance is required rather than lower power consumption. Therefore, in the cloud field 801, high-performance CPUs, high-performance GPUs, large-scale SoCs (System on a Chip), etc. are used. Also, lower down in the hierarchy, lower power consumption is required rather than processing performance, and the number of devices also explodes. A communication device according to one aspect of the present invention can be suitably used for a communication device of an IoT terminal device that requires low power consumption.

[0304] Note that "endpoint" refers to the terminal area of the embedded field 802. Examples of devices used for endpoints include microcontrollers used in factories, home appliances, infrastructure, agriculture, etc.

[0305] Fig. 17 shows an image diagram of factory automation as an application example of an endpoint microcontroller. The factory 884 is connected to the cloud 883 via an Internet line (Internet). Also, the cloud 883 is connected to the home 881 and the office 882 via the Internet line. The Internet line may be a wired communication method or a wireless communication method. For example, in the case of a wireless communication method, wireless communication conforming to a communication standard such as the 4th generation mobile communication system (4G) or the 5th generation mobile communication system (5G) may be performed using a communication device according to one aspect of the present invention in the communication device. Also, the factory 884 may be connected to the factories 885 and 886 via the Internet line.

[0306] The factory 884 has a master device (control device) 831. The master device 831 is connected to the cloud 883 and has a function of exchanging information. Also, the master device 831 is connected to a plurality of industrial robots 842 included in the IoT terminal device 841 via an M2M (Machine to Machine) interface 832. As the M2M interface 832, for example, industrial Ethernet (Ethernet is a registered trademark), which is a type of wired communication method, or local 5G, which is a type of wireless communication method, may be used.

[0307] The factory manager can connect to the factory 884 via the cloud 883 from the home 881 or the office 882 to know the operating status and so on. Also, defective product / missing product checks, location instructions, tact time measurement, etc. can be carried out.

[0308] In recent years, factories labeled as "smart factories" have been globally promoting the introduction of IoT into factories. In cases of smart factories, it has been reported that not only simple inspections and audits by endpoint microcontrollers but also fault detection and anomaly prediction are carried out.

[0309] Small-scale systems such as endpoint microcontrollers often have low overall system power consumption during operation, so the power reduction effect during standby operation by Noff-CPU is significant. On the other hand, in the field of IoT integration, instant responsiveness may be required, but by using Noff-CPU, a fast return from standby operation can be achieved.

[0310] The configurations, structures, methods, etc. shown in this embodiment can be used in appropriate combination with those shown in other embodiments.

Explanation of Reference Numerals

[0311] 10: Wireless transceiver, 11: Antenna, 20: Combiner, 21: Control circuit, 23: Local oscillator, 30: Signal, 31: Power amplifier, 32: Band-pass filter, 33: Mixer, 34: Band-pass filter, 35: Modulator, 36: Signal, 40: Signal, 41: Low-noise amplifier, 42: Band-pass filter, 43: Mixer, 44: Band-pass filter, 45: Demodulator, 46: Signal, 51: Transistor, 52: Transistor, 53: Resistor, 54: Resistor, 55: Inductor, 56: Inductor, 61: Transistor, 62: Transistor, 63: Resistor, 64: Resistor, 65: Inductor, 66: Inductor, 72: Resistor, 100: Substrate, 102: Insulator, 104: Insulator, 106: Insulator, 108: Insulator, 110: Insulator, 112: Insulator, 114: Insulator, 116: Insulator, 118: Insulator, 120: Insulator, 122: Insulator, 124: Insulator, 126: Insulator, 130: Conductor, 132: Conductor, 132a: Conductor, 132b: Conductor, 132c: Conductor, 132d: Conductor, 132e: Conductor, 133: Region, 134: Conductor, 134a: Conductor, 134b: Conductor, 134c: Conductor, 134d: Conductor, 134e: Conductor, 136a: Conductor, 136b: Conductor, 136c: Conductor, 136d: Conductor, 136e: Conductor, 138: Conductor, 138a: Conductor, 138b: Conductor, 140: Capacitor, 140a: Capacitor, 141: Resistor, 142: AC power supply, 144: Capacitor, 200: Transistor, 200A: Transistor, 200B: Transistor, 203: Conductor, 203a: Conductor, 203b: Conductor, 204: Insulator, 213: Insulator, 230: Metal oxide, 230a: Metal oxide, 230b: Metal oxide, 245: Insulator, 252: Insulator, 711: Substrate, 712: Circuit region, 713: Separation region, 714: Separation line, 715: Chip, 750: Electronic component, 752: Printed circuit board, 753: Communication device, 754: Mounting substrate, 755: Lead, 801: Cloud field, 802: Embedded field, 804: Power consumption, 805: Processing performance, 831: Master device, 832: M2M interface, 841: IoT terminal device, 842: Industrial robot, 881: Home, 882: Office, 883: Cloud, 884: Factory, 885: Factory, 886: Factory, 6100: Mobile information terminal, 6101: Housing, 6102: Display unit6103: Band, 6105: Operation Button, 6200: Portable Information Terminal, 6201: Housing, 6202: Display Unit, 6203: Operation Button, 6204: Speaker, 6205: Microphone, 6209: Fingerprint Sensor, 6300: Cleaning Robot, 6301: Housing, 6302: Display Unit, 6303: Camera, 6304: Brush, 6305: Operation Button, 6310: Dust, 6400: Robot, 6401: Illuminance Sensor, 6402: Microphone, 6403: Upper Camera, 6404: Speaker, 6405: Display Unit, 6406: Lower Camera, 6407: Obstacle Sensor, 6408: Moving Mechanism, 6409: Arithmetic Unit, 6500: Aircraft, 6501: Propeller, 6502: Camera, 6503: Battery, 6504: Electronic Components, 7160: Automobile, 8000: Display Device, 8001: Housing, 8002: Display Unit, 8003: Speaker Unit, 8004: Communication Device, 8005: Power Storage Device, 8100: Lighting Device, 8101: Housing, 8102: Light Source, 8103: Communication Device, 8104: Ceiling, 8105: Power Storage Device, 8200: Indoor Unit, 8201: Housing, 8202: Air Outlet, 8203: Communication Device, 8204: Outdoor Unit, 8205: Power Storage Device, 8300: Electric Refrigerator-Freezer, 8301: Housing, 8302: Refrigerator Door, 8303: Freezer Door, 8304: Communication Device, 8305: Power Storage Device, 8405: Side Wall, 8406: Floor, 8407: Window,

Claims

1. An antenna, a duplexer electrically connected to the antenna, and a control circuit electrically connected to the duplexer, wherein the duplexer has a function of realizing transmission and reception of radio signals by the antenna, the control circuit has a function of controlling the operation of the duplexer, the duplexer includes a first transistor, a second transistor, a first resistor, a second resistor, a third transistor, a fourth transistor, a third resistor, and a fourth resistor, a transmission terminal of the duplexer is electrically connected to one of a source or a drain of the first transistor and one of a source or a drain of the second transistor, a reception terminal of the duplexer is electrically connected to one of a source or a drain of the third transistor and one of a source or a drain of the fourth transistor, an antenna terminal of the duplexer is electrically connected to the other of a source or a drain of the second transistor and the other of a source or a drain of the fourth transistor, a gate of the first transistor is electrically connected to one terminal of the first resistor, a gate of the second transistor is electrically connected to one terminal of the second resistor, a gate of the third transistor is electrically connected to one terminal of the third resistor, a gate of the fourth transistor is electrically connected to one terminal of the fourth resistor, a first control terminal of the duplexer is electrically connected to the other terminal of the second resistor and the other terminal of the third resistor, a second control terminal of the duplexer is electrically connected to the other terminal of the first resistor and the other terminal of the fourth resistor, the other of a source or a drain of the first transistor and the other of a source or a drain of the third transistor have a function of supplying a constant potential, a communication device.

2. The communication device according to claim 1, wherein the second transistor and the fourth transistor include an oxide semiconductor in a channel formation region.

3. The communication device according to claim 1, wherein the first transistor to the fourth transistor include an oxide semiconductor in a channel formation region.

Images