Semiconductor device

Abstract

To provide a low-power semiconductor device capable of stable operation.SOLUTION: A semiconductor device includes a logic circuit 102D providing a circuit configuration of transistors having oxide semiconductor in channel formation regions. The transistors configuring the logic circuit respectively include gates and back gates. Input terminals IN1B, IN2B are electrically connected to either the gate or the back gate of the transistors 135, 136 electrically connected to wiring VDDL giving high power supply potential. An output terminal OUT is connected to the other of the gate or the back gate of the transistors 135, 136 electrically connected to wiring VDDL. An output terminal OUTB is connected to either source or drain of the transistors 133, 134 electrically connected to wiring VSSL giving low power supply potential, and the gate or the back gate of the transistors 133, 134 are electrically connected to the input terminals IN1B, IN2B.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] One embodiment of the present invention relates to a semiconductor device.

[0002] Another embodiment of the present invention relates to a semiconductor device. The technical field of the invention disclosed in the present specification and the like is not limited to the following. Alternatively, one aspect of the present invention relates to a process, a machine, a manufacture , or composition of matter.

[0003] In this specification and the like, a semiconductor device is a device that can function by utilizing semiconductor characteristics. Refers to devices in general. Display devices, light-emitting devices, storage devices, electro-optical devices, power storage devices, control systems , semiconductor circuits and electronic devices may include semiconductor devices. [Background technology]

[0004] A transistor whose channel formation region is made of metal oxide (also called an oxide semiconductor) ( Since the leakage current (off-state current) that flows when the transistor is off is extremely small, low power consumption is achieved. It is expected to be applied to logic circuits for low power consumption. For example, in Patent Document 1, A unipolar inverter circuit consisting of OS transistors has been proposed. do. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] US Patent Application Publication No. 2011 / 84731 Summary of the Invention [Problem to be solved by the invention]

[0006] When a logic circuit is constructed using only n-channel transistors, the output voltage drops by the threshold voltage. In addition, a through current flows between the power supply lines, which increases power consumption. The problem arises of increased force.

[0007] In addition, in transistors whose channel formation region is made of silicon (Si transistors), When the transistors that make up the logic circuit are exposed to high temperatures, their electrical characteristics change. Fluctuations in the electrical characteristics lead to a decrease in the on / off ratio of the transistor, which makes it difficult to maintain normal circuit operation. This will cause problems such as not being able to do so.

[0008] In view of the above problems, one embodiment of the present invention is to provide a highly reliable semiconductor device. Another object of one embodiment of the present invention is to provide a semiconductor device that is excellent in low power consumption. This is one of the challenges.

[0009] The description of these problems does not preclude the existence of other problems. It is not necessary for one embodiment to solve all of these problems. The subject matter will be self-evident from the description, drawings, claims, etc. It is possible to extract other issues from the drawings, claims, etc. [Means for solving the problem]

[0010] One aspect of the present invention is a circuit including a first input terminal and a second input terminal, a first output terminal and a second output terminal. a terminal, a first wiring, a second wiring, and first to fourth transistors, The transistor has either a source or a drain electrically connected to the first wiring, and a gate or a barrier One of the gates is electrically connected to the first input terminal, and the other of the source or drain and and the other of the gate and the back gate is electrically connected to a second output terminal, The transistor has either a source or a drain electrically connected to the first wiring, and a gate or a back One of the gates is electrically connected to the second input terminal, and the other of the source or drain and the gate The other of the gate or the back gate is electrically connected to the first output terminal, and the third transistor , the gate and the back gate are electrically connected to the first input terminal, and the source or drain One of the source and drain is electrically connected to the first output terminal, and the other of the source and drain is electrically connected to the second wiring. The fourth transistor has a gate and a back gate electrically connected to the second input terminal. the source or the drain is electrically connected to the second output terminal, and the source Alternatively, the other of the drains is electrically connected to the second wiring.

[0011] One aspect of the present invention is a circuit including a first input terminal and a second input terminal, a first output terminal and a second output terminal. a terminal, first to third wirings, and first to eighth transistors, In the case of the transistor, either the source or the drain is electrically connected to the first wiring, and the gate or the back gate is electrically connected to the first wiring. One of the gates is electrically connected to a first input terminal, and the other of the source or drain and the gate The other of the gate and back gate of the second transistor is electrically connected to the gate and back gate of the second transistor. The second transistor has one of its source and drain electrically connected to the second wiring. the other of the source and the drain is electrically connected to the second output terminal, The transistor has either a source or a drain electrically connected to the first wiring, and a gate or a back One of the gates is electrically connected to the second input terminal, and the other of the source or drain and the gate The other of the gate and back gate is electrically connected to the gate and back gate of the fourth transistor. The fourth transistor has one of its source and drain electrically connected to the second wiring. the other of the source and the drain is electrically connected to the first output terminal, and the fifth transistor The gate and back gate of the transistor are electrically connected to the first input terminal, and the source or drain One of the drains is electrically connected to the gate and back gate of the fourth transistor, and The other of the gate and drain of the sixth transistor is electrically connected to the third wiring. and the back gate are electrically connected to the first input terminal, and one of the source and the drain is 1 electrically connected to the output terminal, and the other of the source or drain is electrically connected to the third wiring The seventh transistor has a gate and a back gate electrically connected to the second input terminal. and either the source or the drain is electrically connected to the gate and back gate of the second transistor. the other of the source and the drain is electrically connected to the third wiring, and the eighth transistor The transistor has a gate and a back gate electrically connected to the second input terminal, and a source or One of the drains is electrically connected to the second output terminal, and the other of the source or drain is electrically connected to the third output terminal. The semiconductor device is electrically connected to the wiring.

[0012] In one aspect of the present invention, a first potential applied to the first wiring is higher than a second potential applied to the second wiring. Semiconductor devices with a capacitance higher than 100 Ω are preferred.

[0013] In one embodiment of the present invention, the first to fourth transistors each have a metal oxide layer in a channel formation region. The semiconductor device is preferably a transistor having a structure.

[0014] In one embodiment of the present invention, the first to eighth transistors each have a metal oxide layer in a channel formation region. The semiconductor device is preferably a transistor having a structure.

[0015] In one embodiment of the present invention, the metal oxide contains at least In (indium) or Zn ( A semiconductor device containing either one of the following is preferred:

[0016] In one embodiment of the present invention, the metal oxide is preferably a semiconductor device containing Ga (gallium). It's nice.

[0017] One aspect of the present invention is a method for switching a switching element including a plurality of switch circuits and a plurality of logic circuits, the logic circuits including: First and second input terminals, first and second output terminals, and first to third The first transistor has a source or a drain. One of the inputs is electrically connected to the first wiring, and one of the gate or back gate is connected to the first input. The other of the source or drain and the gate or back gate are electrically connected to the terminals. the other end is electrically connected to the gate and back gate of the second transistor, The transistor has one of its source and drain electrically connected to the second wiring. The other of the drains is electrically connected to the second output terminal, and the third transistor has a source or drain One of the drains is electrically connected to the first wiring, and one of the gate or back gate is connected to the second input. The other of the source or drain and the gate or backgate are electrically connected to the input terminal. The other end of the transistor is electrically connected to the gate and back gate of the fourth transistor. The transistor has one of the source and the drain electrically connected to the second wiring. The other drain is electrically connected to the first output terminal, and the fifth transistor has a gate and The back gate is electrically connected to the first input terminal, and either the source or the drain is connected to the fourth gate. It is electrically connected to the gate and back gate of the transistor and is connected to the source or drain as well. The sixth transistor has a gate and a back gate electrically connected to the third wiring. 1 input terminal, and either the source or the drain is electrically connected to the first output terminal. The other of the source and the drain is electrically connected to the third wiring. The gate and back gate of the transistor are electrically connected to the second input terminal, and the source or drain One of the inputs is electrically connected to the gate and back gate of the second transistor, and the other of the inputs is electrically connected to the source The other of the drains is electrically connected to the third wiring, and the eighth transistor has a gate and a and the back gate is electrically connected to the second input terminal, and one of the source and the drain is The other of the source and drain is electrically connected to the third wiring. It is a semiconductor device.

[0018] In one aspect of the present invention, a first potential applied to the first wiring is higher than a second potential applied to the second wiring. Semiconductor devices with a capacitance higher than 100 Ω are preferred.

[0019] In one embodiment of the present invention, the first to eighth transistors each have a metal oxide layer in a channel formation region. The semiconductor device is preferably a transistor having a structure.

[0020] In one embodiment of the present invention, the switch circuit includes a transistor. A semiconductor device that is a transistor having a metal oxide in the channel forming region is preferred.

[0021] In one aspect of the present invention, any one of the plurality of switch circuits is in a non-conducting state. A semiconductor device having a function of holding a potential corresponding to data held in a logic circuit is preferred. It's nice.

[0022] In one embodiment of the present invention, the metal oxide contains at least In (indium) or Zn ( A semiconductor device containing zinc is preferred.

[0023] In one embodiment of the present invention, the metal oxide is preferably a semiconductor device containing Ga (gallium). stomach.

[0024] Other aspects of the present invention will be described in the following embodiments and and as described in the drawings. [Effects of the Invention]

[0025] One embodiment of the present invention can provide a highly reliable semiconductor device. According to one embodiment, a semiconductor device excellent in low power consumption can be provided.

[0026] Other aspects of the present invention will be described in the following embodiments and and as described in the drawings. [Brief explanation of the drawings]

[0027] [Figure 1] 1A and 1B are a block diagram and a circuit diagram illustrating a configuration example of a semiconductor device. [Figure 2] 1A is a circuit diagram illustrating an example of the configuration of a semiconductor device, FIG. 1B is a timing chart, and FIG. 1C is a diagram showing circuit symbols. [Figure 3] 1A and 1B are circuit symbols and graphs illustrating an example of the configuration of a semiconductor device. [Figure 4] FIG. 1 is a circuit diagram illustrating a configuration example of a semiconductor device. [Figure 5]1A and 1B are circuit diagrams illustrating a configuration example of a semiconductor device. [Figure 6] 1A and 1B are circuit diagrams and timing charts illustrating an example of the configuration of a semiconductor device. [Figure 7] FIG. 1 is a circuit diagram illustrating a configuration example of a semiconductor device. [Figure 8] 1A and 1B are perspective views illustrating a configuration example of a semiconductor device. [Figure 9] 1A is a block diagram, FIG. 1B is a circuit diagram, and FIG. 1C is a circuit diagram illustrating a configuration example of a semiconductor device. [Figure 10] 1A to 1D are diagrams illustrating circuit symbols, (B) diagrams illustrating circuit symbols, (C) circuit diagrams, and (D) timing charts, each illustrating a configuration example of a semiconductor device. [Figure 11] 1A, 1B, 1C, and 1D are circuit diagrams illustrating examples of the configuration of a semiconductor device. [Figure 12] 1A and 1B are circuit diagrams and circuit symbol symbols, respectively, illustrating an example of the configuration of a semiconductor device. [Figure 13] 1A and 1B are circuit diagrams and circuit symbol symbols, respectively, illustrating an example of the configuration of a semiconductor device. [Figure 14] 1 is a timing chart illustrating a configuration example of a semiconductor device. [Figure 15] 1A and 1B are circuit diagrams illustrating a configuration example of a semiconductor device. [Figure 16] FIG. 1 is a circuit diagram illustrating a configuration example of a semiconductor device. [Figure 17] 1A and 1B are cross-sectional views illustrating examples of the structure of a transistor. [Figure 18] 1A to 1C are a top view, a cross-sectional view, and a cross-sectional view illustrating an example of a transistor structure. [Figure 19] 1A to 1C are a top view, a cross-sectional view, and a cross-sectional view illustrating an example of a transistor structure. [Figure 20] 1A to 1C are a top view, a cross-sectional view, and a cross-sectional view illustrating an example of a transistor structure. [Figure 21]1A to 1C are a top view, a cross-sectional view, and a cross-sectional view illustrating an example of a transistor structure. [Figure 22] 1A to 1C are a top view, a cross-sectional view, and a cross-sectional view illustrating an example of a transistor structure. [Figure 23] 1A to 1D are diagrams showing configuration examples of an electronic device. [Figure 24] 6A and 6B are graphs illustrating the operation of the semiconductor device. DETAILED DESCRIPTION OF THE INVENTION

[0028] Hereinafter, embodiments will be described with reference to the drawings. It is possible to implement the invention in various ways without departing from the spirit and scope of the invention. It will be readily apparent to those skilled in the art that various modifications may be made to the mode and details of the present invention. The present invention should not be construed as being limited to the description of the following embodiments.

[0029] In this specification, the ordinal numbers "first," "second," and "third" refer to the constituent elements. The numbers are added to avoid confusion and do not limit the number of components. The order of the components is not limited. The element referred to as "first" in one embodiment may be used in other embodiments or in the claims. In addition, for example, the second component may be the component referred to as "second" in the specification. A component referred to as "first" in one embodiment may be used in other embodiments, or It may be omitted in the claims.

[0030] In the drawings, elements that are the same or have similar functions, elements that are made of the same material, or In some cases, the same reference numerals may be used to designate elements that are formed at the same time, and repeated explanations thereof will be omitted. It may be omitted.

[0031] In this specification, the term "metal oxide" is used in a broad sense. Metal oxides are oxide insulators, oxide conductors (transparent oxide conductors, They are divided into semiconductors, oxide semiconductors, etc. It is classified as.

[0032] For example, when a metal oxide is used in a channel formation region of a transistor, the metal oxide In other words, metal oxides have amplifying, rectifying, and When the metal oxide has at least one switching function, the metal oxide is called a metal oxide semiconductor. (metal oxide semiconductor). Specifically, a transistor having a metal oxide in a channel formation region is called an "oxide semiconductor transistor." Similarly, the above-mentioned “oxide semiconductor transistor” can be called an “OS transistor.” The "transistor using this method" is also a transistor having a metal oxide in a channel formation region.

[0033] (Embodiment 1) The structure of a semiconductor device according to one embodiment of the present invention will be described.

[0034] FIG. 1A is a block diagram of a semiconductor device according to this embodiment. The semiconductor device 100 can be roughly divided into a signal generating circuit 101 and a logic circuit 102. do.

[0035] In this specification, a semiconductor device is a device that can function by utilizing semiconductor characteristics. Therefore, the signal generating circuit 101 and the logic circuit 102 are semiconductor devices. It is sometimes called.

[0036] The signal generating circuit 101 receives an input signal and an inverted input signal from a terminal IN and a terminal INB. The signal generating circuit 101 is a circuit ( The signal generating circuit 101 uses a CMOS circuit to generate a sequential It can be configured by appropriately designing circuits and combinational circuits.

[0037] The logic circuit 102 has a circuit (illustrated as OS / Cir.) configured with OS transistors. The logic circuit 102 is a combinational circuit. For example, an inverter circuit (NO The logic circuit 102 is a terminal that operates in response to an input signal and an inverted output signal. The output signal and inverted output signal are output from the terminal OUT and terminal OUTB. .

[0038] The logic circuit 102 is a two-wire combinational circuit made up of OS transistors. Unlike Si transistors, transistors have little fluctuation in electrical characteristics in high temperature environments. Therefore, it is possible to achieve highly reliable operation even in a high temperature environment.

[0039] FIG. 1B is a circuit diagram showing a specific circuit configuration of the logic circuit 102. The logic circuit 102 shown in B) is a two-wire logic circuit that functions as an inverter circuit.

[0040] The logic circuit 102 shown in FIG. 1B includes transistors 111 to 114. FIG. 1B also shows a wiring VDDL to which a high power supply potential VDD is applied and a wiring VDDL to which a low power supply potential VDD is applied. The wiring VSSL to which the power supply potential VSS (for example, ground potential) is applied is shown.

[0041] One of the gate and back gate of the transistor 111 is a terminal to which an input signal is applied. Either the source or the drain of the transistor 111 is connected to the wiring VDDL The other of the source and drain of the transistor 111 is connected to The gate or back gate of the transistor 111 is connected to the terminal OUTB. The other terminal is connected to the terminal OUTB that outputs the inverted output signal. It is possible to do this.

[0042] The transistor 111 is turned on or off depending on the potential applied to the gate. or non-conducting (also called OFF), and the terminal OUTB is set to a high level based on the potential VDD. The transistor 111 has a function of controlling whether or not the potential applied to the back gate is Depending on the potential applied, the transistor can be either depletion type (also called normally-on) or It has the function of controlling the transistor type (normally off) or enhancement type. The transistor 111 is also called a first transistor.

[0043] The gate or back gate of the transistor 112 is supplied with an inverted input signal. One of the source and drain of the transistor 112 is connected to the wiring V The other of the source and drain of the transistor 112 is connected to The gate or back gate of the transistor 112 is connected to the output terminal OUT. The other is connected to a terminal OUT that outputs an output signal.

[0044] The transistor 112 is turned on or off depending on the potential applied to the gate, and the terminal It has the function of controlling whether or not OUT is set to a high level potential based on the potential VDD. The transistor 112 changes its normal state in response to the potential applied to the back gate. The transistor 112 has a function of being controlled to be on or normally off. Also called a Transformer.

[0045] The gate and back gate of the transistor 113 are connected to a terminal IN to which an input signal is applied. Either the gate or the back gate of the transistor 113 is connected to the terminal The source or drain of the transistor 113 may be connected to IN. The source or drain of the transistor 113 is connected to a terminal OUT that outputs an output signal. The other end of the drain is connected to the wiring VSSL.

[0046] The transistor 113 is turned on in response to the potential of the terminal IN applied to the gate and back gate. , it turns on or off, and whether the terminal OUT is set to a low level potential based on the potential VSS. The transistor 113 has a function of controlling whether or not the transistor 113 is a third transistor.

[0047] The gate and back gate of the transistor 114 are connected to a terminal I NB. Either the gate or the back gate of the transistor 114 is connected to the The source or drain of the transistor 114 may be connected to the terminal INB. One of the terminals is connected to a terminal OUTB that outputs an inverted output signal. The other of the source and the drain is connected to the wiring VSSL.

[0048] The transistor 114 is turned on in response to the potential of the terminal INB applied to the gate and back gate. This turns the terminal OUTB on or off, setting it to a low-level potential based on the potential VSS. The transistor 114 has a function of controlling whether or not the transistor 114 is turned on. cormorant.

[0049] Next, the operation of the logic circuit 102 shown in FIG. 1B will be explained using FIGS. 2A to 2C. and explain.

[0050] Figure 2(A) shows a circuit diagram similar to Figure 1(B), and Figure 2(B) shows the operation of Figure 2(A). 10 shows a timing chart for explaining the above.

[0051] In the timing chart shown in FIG. 2B, the time T1 to T2 and the time T3 In the periods T1 to T4, the input signal applied to the terminal IN is at a high level, and the inverted input signal applied to the terminal INB is at a low level. The transistor 111 is normally on, and the transistor 113 is normally off. The transistor 112 is normally off, and the transistor 114 is off. The terminal OUTB is at a low level based on the potential VSS. This results in a high level potential.

[0052] By adopting this structure, the potential applied to the back gate of the transistor can be switched. For example, in the circuit symbol of the transistor 115 illustrated in FIG. The gate of the transistor is g, the back gate of the transistor is bg, and the The source potential is s and the drain potential is d. The current (Id) flowing through the drain of a transistor and the voltage (Vg) at the gate when 0V is applied. As shown in the figure, the voltage at the back gate is the potential VSS (Vb g=0) to shift the threshold voltage positively and make it normally off. In addition, the voltage at the back gate is set to the potential VDD (Vbg=VDD) to minimize the threshold voltage. It can be inversely shifted to a normally-on state.

[0053] A high-level potential is applied to the back gate of the transistor 111. A low level potential is applied to the back gate of transistor 112. 11 is a normally-on transistor, and transistor 112 is a normally-off transistor. The transistor 111 functions as a normally-on transistor. This allows the amount of current flowing through the OUTB terminal to be increased. Since the transistor 112 can function as a normally-off transistor, the wiring V The through current between the DDL and the wiring VSSL can be reliably reduced.

[0054] In the timing chart shown in FIG. 2B, between times T2 and T3, the terminal IN The input signal to be applied to terminal INB is set to low level, and the inverted input signal to terminal INB is set to high level. The transistor 111 is normally off, and the transistor 113 is off. 112 is normally on, and transistor 114 is on. The terminal OUT is at the potential VDD. The terminal OUTB is at a high level potential based on the potential VSS. become.

[0055] A low-level potential is applied to the back gate of the transistor 111. A high-level potential is applied to the back gate of transistor 112. 11 is a normally-off transistor, and transistor 112 is a normally-on transistor. The transistor 111 functions as a normally-off transistor. This ensures that the through current between the VDDL and VSSL wirings can be reduced. In addition, the transistor 112 can be made to function as a normally-on transistor. This allows the amount of current flowing through the OUT terminal to be increased.

[0056] The circuit diagram of the logic circuit 102 shown in FIG. 2A functions as a two-wire inverter circuit. Figure 2(C) shows the circuit symbol for a two-wire system.

[0057] In FIG. 1B, the back gates of the transistors 111 and 112 are 4 shows the configuration in which the terminals IN and INB are connected. As shown in the circuit diagram of circuit 102A, the terminals IN and INB are connected to the gate side. That's fine.

[0058] In a transistor, the thickness of the gate insulating film on the gate side or the gate insulating film on the back gate side The thickness of the membrane is changed. Then, by switching the connection between Figure 1(B) and Figure 4, the channel Therefore, the shift amount of the threshold voltage can be adjusted. The gate insulating film on the side where the terminals IN and INB are connected can be By adopting this configuration, the input signal to the terminal IN and the terminal INB This makes it possible to improve the switching characteristics of the input signal and the inverted input signal.

[0059] By using the above-described configuration, a semiconductor device having a logic circuit configured with OS transistors can be realized. The device can achieve highly reliable operation and low power consumption. This can be done.

[0060] Next, a configuration example of a logic circuit different from that shown in FIG. 1B will be described.

[0061] The logic circuit 102B shown in FIG. 5A functions as an inverter circuit in the same manner as in FIG. 1B. FIG. 1 is a circuit diagram of a two-wire logic circuit.

[0062] The logic circuit 102B shown in FIG. 5A includes transistors 121 to 122. 5A also shows a wiring VDHL to which a high power supply potential VDH is applied, a high power supply potential VDH, and a Wiring VDDL to which potential VDD is applied, and wiring VSS to which low power supply potential VSS is applied The high power supply potential VDH is higher than the high power supply potential VDD.

[0063] One of the gate and back gate of the transistor 121 is a terminal to which an input signal is applied. One of the source and drain of the transistor 121 is connected to the wiring VDHL The other of the source and drain of the transistor 121 is connected to the 2. The gate or back gate of transistor 121 is connected to the The other gate is connected to the gate and back gate of the transistor 122 .

[0064] The transistor 121 is turned on or off depending on the potential applied to the gate. Whether the potential of the gate and back gate of the transistor 122 is set to a potential based on the potential VDH. The transistor 121 has a function of controlling whether the transistor 121 is turned on or off in response to a potential applied to the back gate. This has the function of controlling whether the transistor is normally on or normally off. The transistor 121 is also referred to as a first transistor.

[0065] One of the source and drain of the transistor 122 is connected to the wiring VDDL. The other of the source or the drain of the transistor 122 is connected to the terminal OUTB.

[0066] The transistor 122 is turned on or off depending on the potentials applied to the gate and back gate. is turned off, and controls whether or not the terminal OUTB is set to a high level potential based on the potential VDD. The transistor 122 is also referred to as a second transistor.

[0067] The gate or back gate of the transistor 123 is supplied with an inverted input signal. One of the source and drain of the transistor 123 is connected to the wiring V The other of the source and drain of the transistor 123 is connected to the transistor The gate and back gate of the transistor 123 are connected to the gate and back gate of the transistor 124. The other back gate is connected to the gate and back gate of transistor 124 .

[0068] The transistor 123 is turned on or off depending on the potential applied to the gate. Whether the potential of the gate and back gate of the transistor 124 is set to a potential based on the potential VDH. The transistor 123 has a function of controlling whether the transistor 123 is turned on or off in response to a potential applied to the back gate. This has the function of controlling whether the transistor is normally on or normally off. The transistor 123 is also referred to as a third transistor.

[0069] One of the source and drain of the transistor 124 is connected to the wiring VDDL. The other of the source or drain of the transistor 124 is connected to the terminal OUT.

[0070] The transistor 124 is turned on or off depending on the potentials applied to the gate and back gate. is turned off, and controls whether or not the terminal OUT is set to a high level potential based on the potential VDD. The transistor 124 is also referred to as a fourth transistor.

[0071] The gate and back gate of the transistor 125 are connected to a terminal IN to which an input signal is applied. Either the gate or the back gate of the transistor 125 is connected to the terminal The source or drain of the transistor 125 may be connected to IN. is connected to the gate and back gate of transistor 124. The other of the source and drain is connected to the wiring VSSL.

[0072] The transistor 125 is turned on in response to the potential of the terminal IN applied to the gate and back gate. , and the potential of the gate and back gate of the transistor 124 is set to potential The transistor 1 has a function of controlling whether or not to set the potential to a low level based on VSS. 25 is also called the fifth transistor.

[0073] The gate and back gate of the transistor 126 are connected to a terminal IN to which an input signal is applied. Either the gate or the back gate of the transistor 126 is connected to the terminal The source or drain of the transistor 126 may be connected to the input terminal of the The source or drain of the transistor 126 is connected to a terminal OUT that outputs an output signal. The other end of the drain is connected to the wiring VSSL.

[0074] The transistor 126 is turned on in response to the potential of the terminal IN applied to the gate and back gate. , it turns on or off, and whether the terminal OUT is set to a low level potential based on the potential VSS. The transistor 126 has a function of controlling whether or not the transistor 126 is turned on.

[0075] The gate and back gate of the transistor 127 are connected to the terminal I NB. Either the gate or the back gate of the transistor 127 The source or drain of the transistor 127 may be connected to the terminal INB. One of the terminals is connected to the gate and back gate of the transistor 122. The other of the source or the drain of the capacitor 127 is connected to the wiring VSSL.

[0076] The transistor 127 is turned on in response to the potential of the terminal INB applied to the gate and back gate. This turns the transistor 122 on or off, and the potentials of the gate and back gate of the transistor 122 are changed. The transistor has a function of controlling whether or not to set the potential to a low level based on the potential VSS. 127 is also called the seventh transistor.

[0077] The gate and back gate of the transistor 128 are connected to the terminal I NB. Either the gate or the back gate of the transistor 128 The source or drain of the transistor 128 may be connected to the terminal INB. One of the terminals is connected to a terminal OUTB that outputs an inverted output signal. The other of the source and the drain is connected to the wiring VSSL.

[0078] The transistor 128 is turned on in response to the potential of the terminal INB applied to the gate and back gate. This turns the terminal OUTB on or off, setting it to a low-level potential based on the potential VSS. The transistor 128 has a function of controlling whether or not the transistor 128 is turned on. The transistor 128 is also referred to as an eighth transistor.

[0079] In FIG. 5A, the back gates of the transistors 121 and 123 are 5B shows the configuration for connecting the terminals IN and INB. As shown in the circuit diagram of the logic circuit 102C, the terminals IN and INB are connected to the gate side. It may also be composed.

[0080] In a transistor, the thickness of the gate insulating film on the gate side or the gate insulating film on the back gate side By changing the thickness of the velum, and switching the connection between Figure 5(A) and Figure 5(B), The electric field strength in the channel formation region can be adjusted. Therefore, the shift amount of the threshold voltage It is possible to adjust the gate insulation resistance on the side where the terminals IN and INB are connected. The film is preferably thin. By adopting this configuration, the film is able to provide the terminals IN and INB with a high The switching characteristics of the input signal and the inverted input signal can be improved.

[0081] Next, the operation of the logic circuit 102B shown in FIG. 5A will be explained with reference to FIGS. 6A and 6B. This will be used to explain.

[0082] FIG. 6(A) shows a circuit diagram similar to FIG. 5(A), and FIG. 6(B) shows the operation of FIG. 6(A). 6A is a timing chart for explaining the operation of the transistor 1. The gate and back gate nodes of 22 are shown as nodes P. The gate and back gate nodes of register 124 are shown as nodes PB.

[0083] In the timing chart shown in FIG. 6B, at times T5 to T6 and at time T7 In T1 to T8, the input signal to the terminal IN is at a high level, and the inverted input signal to the terminal INB is at a low level. The transistor 121 is normally on, and the transistors 125 and Transistor 123 is normally off and transistor 126 is turned on. The transistor 127 and the transistor 128 are turned off. The node PB is at the potential VSS, and the transistor 122 is turned on. The terminal OUT is set to the potential VSS. The OUTB terminal is at a low level potential based on the potential VDD. become.

[0084] A high-level potential is applied to the back gate of the transistor 121. A low level potential is applied to the back gate of transistor 123. 21 is a normally-on transistor, and transistor 123 is a normally-off transistor. The transistor 121 functions as a normally-on transistor. Therefore, the amount of current flowing through the gate and back gate of the transistor 122 can be In addition, the transistor 123 can be used as a normally-off transistor. This effectively reduces the through current between the VDHL and VSSL wiring. It is possible.

[0085] In addition, in the configuration of FIG. 6A, the node P is set to a voltage based on the potential VDH, which is higher than the potential VDD. Therefore, the voltage applied between the gate and source of the transistor 122 can be This allows for a larger voltage to be applied, and the voltage drop due to the threshold voltage can be reduced, making it possible to achieve a more reliable The potential of the terminal OUTB can be set to the potential VDD.

[0086] Figures 24(A) and (B) show the input signal (IN) and the inverted input signal (IN) obtained by circuit simulation. The waveform diagrams of the input signal (INB), output signal (OUT), and inverted output signal (OUTB) were obtained. The graphs are shown in Fig. 24(A) and Fig. 24(B) for a power supply voltage of 1.2V and 2.5V, respectively. In either case, an output signal (output voltage) corresponding to the voltage of the input signal (input voltage) is obtained. Ta.

[0087] In the timing chart shown in FIG. 6B, between times T6 and T7, the terminal IN The input signal to be applied to terminal INB is set to low level, and the inverted input signal to terminal INB is set to high level. The transistor 121 is normally off, and the transistors 125 and 126 are The transistor 123 is normally on, and the transistors 127 and The node P is at a low level potential based on the potential VSS, and the transistor 128 is turned on. The transistor 122 is turned off. The node PB is at a high level potential based on the potential VDH. The transistor 124 is turned on. The terminal OUT is at a low level potential based on the potential VSS. The terminal OUTB becomes a high-level potential based on the potential VDD.

[0088] A low-level potential is applied to the back gate of the transistor 121. A high level potential is applied to the back gate of transistor 123. 21 is a normally-off transistor, and transistor 123 is a normally-on transistor. The transistor 121 functions as a normally-off transistor. Therefore, the through current between the wiring VDHL and VSSL can be reliably reduced. In addition, the transistor 123 can be made to function as a normally-on transistor. This increases the amount of current flowing through the gate and back gate of the transistor 124. It is possible.

[0089] In addition, in the configuration of FIG. 6A, the node PB is set to a potential VDH higher than the potential VDD. Therefore, the potential applied between the gate and source of the transistor 124 can be This allows for a larger voltage to be applied, reducing the voltage drop due to the threshold voltage, making it more reliable. The potential of the terminal OUTB can be set to the potential VDD.

[0090] The circuit diagram of the logic circuit 102B shown in FIG. 6(A) is a two-wire inverter circuit. Therefore, as in Figure 2(A), the two-wire circuit symbol shown in Figure 2(C) is used. The symbol can be represented as:

[0091] By using the above-described configuration, a semiconductor device having a logic circuit configured with OS transistors can be realized. The device can achieve highly reliable operation and low power consumption. In addition, a configuration can be achieved in which the voltage drop of the output signal is suppressed.

[0092] Furthermore, by applying the above-described configuration, it is possible to configure a basic combinational circuit. can.

[0093] 7 is a circuit diagram of a logic circuit to which the configuration of FIG. 4 is applied. The logic circuit 102D shown in FIG. 7 includes transistors 131 to 138. Also, in FIG. 10 shows a wiring VDDL to which a low power supply potential VSS is applied, and a wiring VSSL to which a low power supply potential VSS is applied. Terminals IN1, IN1B, IN2 and IN2B are terminals for supplying input signals. OUT and terminal OUTB are terminals that give output signals. An output signal corresponding to the NAND (NOR of the inverted input signal) is obtained from the OUTB terminal. From these, an output signal is obtained according to the NAND of the input signals (logical AND of the inverted input signals). The function of the logic circuit can be changed by switching the signal input to the terminal. The truth table for this path is shown in Table 1.

[0094] [Table 1]

[0095] By using the above combinational circuits, counters, serial-to-parallel converters, processors, These circuits are made up of OS transistors. Therefore, good switching characteristics can be maintained even in high temperature environments. It is also possible to reduce power consumption by reducing through current and suppress voltage drops equivalent to the threshold voltage. etc. can be achieved.

[0096] FIG. 8 shows an example of a perspective view of an IC incorporating the logic circuit, which is a semiconductor device.

[0097] FIG. 8A shows an example of an IC. The IC 7000A shown in FIG. 8A has a lead 700 The IC 7000A is mounted on, for example, a printed circuit board 7002. A plurality of such IC chips are combined and each is mounted on a printed circuit board 700. 2, the board (mounted board 7004) on which the electronic components are mounted is completed. The circuit section 7003A may include various circuits shown in the above embodiments on one die or multiple die. The circuit portion 7003A is divided into several dies. 1, and wiring layer 7032.

[0098] The OS transistor layer may be a single layer or may be stacked with a wiring layer sandwiched therebetween. Specifically, another example of an IC is shown in FIG. 8(B). The IC7000B shown in FIG. 8(B) is The IC 7000B has leads 7001 and a circuit portion 7003B. 7002. Multiple such IC chips are combined, and each A substrate (mounting substrate 70) on which electronic components are mounted by being electrically connected on the substrate 7002 In the circuit portion 7003B, various circuits shown in the above embodiment modes are integrated into one device. The circuit section 7003A is provided as an OS transceiver. The OS transistor layer 7031, the wiring layer 7032, and the OS transistor layer 7033 are shown. The transistor layer 7031 is connected to the OS transistor layer 7033 via a wiring layer 7032. On the OS transistor layer 7033, another OS transistor is connected via another wiring layer. It is also possible to use a structure in which multiple OS transistor layers are stacked. Since the circuit portion 7003B can be provided in the same manner, the circuit portion 7003B can be easily miniaturized.

[0099] In Figures 8(A) and (B), the packages of IC7000A and IC7000B are QFP (Qua d Flat Package), but the packaging style is not limited to this. do not have.

[0100] As described above, the configurations, methods, etc. shown in this embodiment may be different from the configurations, methods, etc. shown in other embodiments. They can be used in appropriate combinations.

[0101] (Embodiment 2) A semiconductor device according to one embodiment of the present invention, which is different from the semiconductor device described in Embodiment 1. The configuration will be explained.

[0102] FIG. 9A is a block diagram of a semiconductor device according to this embodiment. The semiconductor device 100A can be roughly divided into a signal generating circuit 101 and a signal processing circuit 201. can be done.

[0103] In this specification, a semiconductor device is a device that can function by utilizing semiconductor characteristics. Therefore, the signal generating circuit 101 and the signal processing circuit 201 may be used separately or are sometimes collectively called a semiconductor device.

[0104] The signal generating circuit 101 outputs an input signal and an inverted input signal from a terminal D and a terminal Db. The signal generating circuit 101 is a circuit made up of Si transistors (Si The signal generating circuit 101 uses a CMOS circuit to generate a sequential circuit. and can be configured by appropriately designing using combinational circuits.

[0105] The signal processing circuit 201 is a circuit configured with OS transistors (illustrated as OS / Cir.). The signal processing circuit 201 includes a sequential circuit and a combinational circuit. Combinational circuits include inverter circuits (also called NOT circuits) and logical product circuits (AN Sequential circuits include flip-flop circuits and counter circuits. The processing circuit 201 processes the input signal and the inverted input signal in an internal circuit and outputs the signal to the terminals Q and and outputs an output signal and an inverted output signal from terminal Qb.

[0106] 9(B) is a circuit diagram showing an example of the circuit of the signal processing circuit 201. ) includes a logic circuit 202 (Seq. in the figure) that functions as a sequential circuit. and a logic circuit 102 (indicated as Comb. in the figure) that functions as a combinational circuit. The circuit configuration is a combination of multiple of these.

[0107] The logic circuit 202 is a two-wire sequential circuit made up of OS transistors. Unlike Si transistors, the electrical characteristics of silicon transistors do not fluctuate much in high temperature environments. Therefore, it is possible to achieve highly reliable operation even in a high temperature environment.

[0108] FIG. 9(C) is a circuit diagram showing a specific circuit configuration of the logic circuit 202. The logic circuit 202 shown in C) is a logic circuit that functions as a switch and an inverter circuit, This is a two-wire flip-flop circuit having the following.

[0109] The logic circuit 202 shown in FIG. 9C receives the clock signal CLK or the inverted clock signal CLK. A switch circuit 203 whose on / off is controlled in response to CLKb, an inverter circuit, and a logic circuit 102 that functions as a

[0110] The logic circuit 102 shown in FIG. 9C is a 2-bit logic circuit as described with reference to FIGS. Figure 10(A) shows a two-wire inverter circuit, similar to Figure 2(C). The logic circuit 102 is connected to a wiring V DHL, the wiring VDDL to which the high power supply potential VDD is applied, and the wiring VDDL to which the low power supply potential VSS is applied. Therefore, the circuit symbols in Figure 2(C) and Figure 10(A) are The symbol can also be represented as the circuit symbol shown in FIG. 10(B). The wiring names given in FIG. 10(B) may be omitted.

[0111] FIG. 10C shows a logic circuit that can be represented by the logic circuit 102B described in FIG. 6A. 10C is a circuit diagram of a specific circuit configuration of the logic circuit 102. The transistors 121 to 128 are included. A wiring VDHL to which VDH is applied, a wiring VDDL to which a high power supply potential VDD is applied, and The wiring VSSL to which the low power supply potential VSS is applied is shown. The high power supply potential VDH is The potential is higher than the high power supply potential VDD. The gate and back gate nodes of the transistor are shown as node P. The node of the gate and back gate of the capacitor 124 is shown as node PB.

[0112] One of the gate and back gate of the transistor 121 is a terminal to which an input signal is applied. One of the source and drain of the transistor 121 is connected to the wiring VDHL The other of the source and drain of the transistor 121 is connected to the 2. The gate or back gate of transistor 121 is connected to the The other gate is connected to the gate and back gate of the transistor 122 .

[0113] The transistor 121 is turned on or off depending on the potential applied to the gate. Whether the potential of the gate and back gate of the transistor 122 is set to a potential based on the potential VDH. The transistor 121 has a function of controlling whether the transistor 121 is turned on or off in response to a potential applied to the back gate. This has the function of controlling whether the transistor is normally on or normally off. The transistor 121 is also referred to as a first transistor.

[0114] One of the source and drain of the transistor 122 is connected to the wiring VDDL. The other of the source or the drain of the transistor 122 is connected to the terminal OUTB.

[0115] The transistor 122 is turned on or off depending on the potentials applied to the gate and back gate. is turned off, and controls whether or not the terminal OUTB is set to a high level potential based on the potential VDD. The transistor 122 is also referred to as a second transistor.

[0116] The gate or back gate of the transistor 123 is supplied with an inverted input signal. One of the source and drain of the transistor 123 is connected to the wiring V The other of the source and drain of the transistor 123 is connected to the transistor The gate and back gate of the transistor 123 are connected to the gate and back gate of the transistor 124. The other back gate is connected to the gate and back gate of transistor 124 .

[0117] The transistor 123 is turned on or off depending on the potential applied to the gate. Whether the potential of the gate and back gate of the transistor 124 is set to a potential based on the potential VDH. The transistor 123 has a function of controlling whether the transistor 123 is turned on or off in response to a potential applied to the back gate. This has the function of controlling whether the transistor is normally on or normally off. The transistor 123 is also referred to as a third transistor.

[0118] One of the source and drain of the transistor 124 is connected to the wiring VDDL. The other of the source or drain of the transistor 124 is connected to the terminal OUT.

[0119] The transistor 124 is turned on or off depending on the potentials applied to the gate and back gate. is turned off, and controls whether or not the terminal OUT is set to a high level potential based on the potential VDD. The transistor 124 is also referred to as a fourth transistor.

[0120] The gate and back gate of the transistor 125 are connected to a terminal IN to which an input signal is applied. Either the gate or the back gate of the transistor 125 is connected to the terminal The source or drain of the transistor 125 may be connected to IN. is connected to the gate and back gate of transistor 124. The other of the source and drain is connected to the wiring VSSL.

[0121] The transistor 125 is turned on in response to the potential of the terminal IN applied to the gate and back gate. , and the potential of the gate and back gate of the transistor 124 is set to potential The transistor 1 has a function of controlling whether or not to set the potential to a low level based on VSS. 25 is also called the fifth transistor.

[0122] The gate and back gate of the transistor 126 are connected to a terminal IN to which an input signal is applied. Either the gate or the back gate of the transistor 126 is connected to the terminal The source or drain of the transistor 126 may be connected to the input terminal of the The source or drain of the transistor 126 is connected to a terminal OUT that outputs an output signal. The other end of the drain is connected to the wiring VSSL.

[0123] The transistor 126 is turned on in response to the potential of the terminal IN applied to the gate and back gate. , it turns on or off, and whether the terminal OUT is set to a low level potential based on the potential VSS. The transistor 126 has a function of controlling whether or not the transistor 126 is turned on.

[0124] The gate and back gate of the transistor 127 are connected to the terminal I NB. Either the gate or the back gate of the transistor 127 The source or drain of the transistor 127 may be connected to the terminal INB. One of the terminals is connected to the gate and back gate of the transistor 122. The other of the source or the drain of the capacitor 127 is connected to the wiring VSSL.

[0125] The transistor 127 is turned on in response to the potential of the terminal INB applied to the gate and back gate. This turns the transistor 122 on or off, and the potentials of the gate and back gate of the transistor 122 are changed. The transistor has a function of controlling whether or not to set the potential to a low level based on the potential VSS. 127 is also called the seventh transistor.

[0126] The gate and back gate of the transistor 128 are connected to the terminal I NB. Either the gate or the back gate of the transistor 128 The source or drain of the transistor 128 may be connected to the terminal INB. One of the terminals is connected to a terminal OUTB that outputs an inverted output signal. The other of the source and the drain is connected to the wiring VSSL.

[0127] The transistor 128 is turned on in response to the potential of the terminal INB applied to the gate and back gate. This turns the terminal OUTB on or off, setting it to a low-level potential based on the potential VSS. The transistor 128 has a function of controlling whether or not the transistor 128 is turned on. The transistor 128 is also referred to as an eighth transistor.

[0128] By adopting this configuration, as explained in FIGS. 3(A) and 3(B), The potential applied to the gate can be switched.

[0129] Next, the operation of the logic circuit 102 shown in FIG. 10(C) will be explained with reference to FIG. 10(D). FIG. 10D is a diagram illustrating the operation of the logic circuit 102 shown in FIG. The timing chart shown in FIG. 10(D) is the same as that shown in FIG. 6(B). This is the same as the timing chart described above.

[0130] In the timing chart shown in FIG. 10(C), the time T11 to T12 and the time At time T13 to T14, the input signal to the terminal IN is at a high level, and the input signal to the terminal INB is at a low level. The inverted input signal is set to a low level. The transistor 121 is normally on. 125 and transistor 126 are turned on. Transistor 123 is normally off. The transistors 127 and 128 are turned off. When the node P is at the potential VDH, The node PB is at a high level potential, and the transistor 122 is turned on. The terminal OUT becomes a low-level potential based on S, and the transistor 124 is turned off. The OUTB terminal is at a low level based on the potential VSS. This is the potential of the capacitor.

[0131] A high-level potential is applied to the back gate of the transistor 121. A low level potential is applied to the back gate of transistor 123. 21 is a normally-on transistor, and transistor 123 is a normally-off transistor. The transistor 121 functions as a normally-on transistor. Therefore, the amount of current flowing through the gate and back gate of the transistor 122 can be In addition, the transistor 123 can be used as a normally-off transistor. This effectively reduces the through current between the VDHL and VSSL wiring. It is possible.

[0132] In addition, in the configuration of FIG. 10C, the node P is set to a potential VDH higher than the potential VDD. Therefore, the potential applied between the gate and source of the transistor 122 can be This allows for a larger voltage to be applied, reducing the voltage drop due to the threshold voltage, making it more reliable. The potential of the terminal OUTB can be set to the potential VDD.

[0133] In the timing chart shown in FIG. 10(D), from time T12 to time T13, The input signal to terminal IN is set to low level, and the inverted input signal to terminal INB is set to high level. The transistor 121 is normally off, and the transistors 125 and 1 Transistor 123 is normally on, transistor 127 and transistor 26 are off. The transistor 128 is turned on. The node P is at a low level potential based on the potential VSS. The node PB is at a high level potential based on the potential VDH. The terminal OUT is at a low level based on the potential VSS. The terminal OUTB becomes a high level potential based on the potential VDD.

[0134] A low-level potential is applied to the back gate of the transistor 121. A high level potential is applied to the back gate of transistor 123. 21 is a normally-off transistor, and transistor 123 is a normally-on transistor. The transistor 121 functions as a normally-off transistor. Therefore, the through current between the wiring VDHL and VSSL can be reliably reduced. In addition, the transistor 123 can be made to function as a normally-on transistor. This increases the amount of current flowing through the gate and back gate of the transistor 124. It is possible.

[0135] In addition, in the configuration of FIG. 10(C), the node PB is set to a potential VDH higher than the potential VDD. Therefore, a potential applied between the gate and source of the transistor 124 can be This allows for a larger voltage to be applied, reducing the voltage drop due to the threshold voltage, making it more reliable. In fact, the potential of the terminal OUTB can be set to the potential VDD.

[0136] The switch circuit 203 shown in FIG. 9C has a two-wire switch. , between terminal IN and terminal OUT, and between terminal INB and terminal OUTB, it is turned on or off. In FIG. 11(A), the clock signal CLK controls the Illustrates the circuit symbol for a two-wire switch that is controlled to be on or off.

[0137] The switch circuit 203 shown in FIG. 11A is the same as the switch circuit 20 shown in FIG. 11B. As shown in 3A, the wiring that gives the clock signal CLK is connected to the gate of each transistor. The on / off control can be performed by using the same.

[0138] Alternatively, the switch shown in FIG. 11(C) may be used. The switch circuit 203B supplies a signal BG to the back gate separately from the wiring that supplies the clock signal CLK. The gate and back gate are connected to the wiring that controls the on / off state depending on the signal. The signal BG is used to control the threshold voltage of the transistor. By using this configuration, it is possible to control the on / off of a transistor. In addition to controlling the voltage, the threshold voltage of the transistor can be controlled.

[0139] Alternatively, the switch shown in FIG. 11(D) may be used. The clock circuit 203C includes wiring for providing a clock signal CLK and a gate and a The back gate can be connected to control the ON / OFF. By using such a structure, the switching characteristics of the transistor can be improved.

[0140] By using the above-described configuration, a semiconductor device having a logic circuit configured with OS transistors can be manufactured. The device can achieve highly reliable operation and low power consumption. In addition, a voltage drop in the output signal can be suppressed.

[0141] Next, a configuration different from the configuration described above will be described.

[0142] FIG. 12(A) is a circuit diagram of a logic circuit to which the configuration of FIG. 10(B) is applied. The logic circuit 102E shown in FIG. 12(A) includes transistors 151 to 165. ) includes wiring VDHL to which a high power supply potential VDH is applied, wiring VDHL to which a high power supply potential VDD is applied, The figure shows a line VDDL and a wiring VSSL to which a low power supply potential VSS is applied. N1, IN1B, IN2 and terminal IN2B are terminals for supplying input signals. The terminal OUTB is a terminal that provides an output signal. The terminal OUT outputs the negation of the input signal. An output signal according to the logical product (NOR of the inverted input signal) is obtained from terminal OUTB. An output signal is obtained according to the logical AND of the input signal (logical AND of the inverted input signal). The function of the logic circuit may be changed by switching the input signal. The truth table of the circuit is the same as Table 1 described in the first embodiment above.

[0143] The logic circuit 102D shown in Figure 12(A) represents a two-wire NAND circuit. The circuit symbol for a two-wire NAND circuit is shown in Figure 12(B). The attached wiring name may be omitted.

[0144] By using the above combinational circuits, counters, serial-to-parallel converters, processors, These circuits are made up of OS transistors. Therefore, good switching characteristics can be maintained even in high temperature environments. It is also possible to reduce power consumption by reducing through current and suppress voltage drops equivalent to the threshold voltage. etc. can be achieved.

[0145] As another example of the configuration, FIG. 13(A) shows a configuration in which data is retained even when the supply of power supply voltage is stopped. By making it possible, a circuit diagram of a power-gating capable logic circuit 202A is illustrated. The logic circuit 202A includes the logic circuit 102 and the switch circuit 203, as well as a reset signal RST and a logic circuit 102E to which an inverted reset signal RSTb is input, a power gating signal The switch circuit 203D is provided with a signal PG and a signal BG.

[0146] The switch circuit 203D is controlled to be turned on or off in response to a signal PG. , which is a signal for holding data during power gating. The transistors that make up the circuit are OS transistors, just like other logic circuits. Therefore, the transistor included in the switch circuit 203D has an extremely small off-state current. By turning it off, the logic circuit 2 is connected to the nodes SN and SNb shown in FIG. It can hold a charge according to the data given to O2A.

[0147] The logic circuit 202A shown in FIG. 13A is an asynchronous reset type and a power gating type. In FIG. 13B, the flip-flop circuit shown in FIG. The circuit symbol symbol is shown.

[0148] Next, the operation of the logic circuit 202A shown in FIG. 13(A) will be described with reference to FIG. FIG. 14 shows timing charts for explaining the operation of the logic circuit 202A shown in FIG. 13(A). Figure 14 shows the timing chart for signal processing (Run) and data backup ( BK), power gating (PG), and data recovery (Recovery) The diagram is shown in the figure.

[0149] In the timing chart shown in FIG. 14, signal processing is performed from time T21 to time T22. At this time, the BG signal is set to low level. As a result, the transistor included in the switch circuit 203D is set to a normally-off state. Between time T22 and time T23, the signal PG is set to a low level. The capacitance element connected to the capacitor holds a charge according to the data.

[0150] Between times T23 and T24, the voltages VDD and VDH are set to low level, and During this time, the current flowing through the nodes SN and SNb can be eliminated. The capacitance element holds a charge according to the data. Therefore, the node SN and the node S The capacitance element connected to Nb continues to hold a charge according to the data.

[0151] At times T24 and T25, the power gating state is changed to the data recovery state. At this time, the voltages VDD and VDH that were set to low level are The OS transistors are turned on when the signal BG is at a low level. Therefore, the node SN and the node SNb are connected to the normally-off state. The capacitive element continues to hold a charge according to the data.

[0152] At times T25 and T26, the clock signal CLK is set to a high level. A signal corresponding to the charge corresponding to the data held in node SN and node SNb is output to node SN. The signal is output from the logic circuit 102 connected to the node SNb to the logic circuit 102E.

[0153] Between times T26 and T27, the clock signal CLK is set to a low level, and the signals BG and The signal PG is set to high level. The data stored in the nodes SN and SNb is Then, after time T27, the clock signal CLK and the inverted clock signal CLKb is applied to execute signal processing.

[0154] The logic circuit 202A includes the logic circuit 102 and the logic circuit 102E described above. Therefore, the through current between the wiring VDHL and wiring VSSL can be reliably reduced.

[0155] The configuration explained in FIG. 13(A) can also be realized in the circuit diagram shown in FIG. 15(A). That is, like the logic circuit 202B, wiring for transmitting an inverted input signal and an inverted output signal is provided. Similarly, the logic circuit 20 shown in FIG. As shown in the circuit diagram of 2C, it can also be realized by replacing the NAND circuit with a NOR circuit. be.

[0156] As another example of the configuration, a logic circuit 202D shown in FIG. 16 is an application of the logic circuit described above. This is a circuit diagram of a 2-bit counter (with asynchronous reset function) shown in Figure 16. The circuit configuration shown can be realized by combining logic circuits having different functions as described above. It is Noh.

[0157] As described above, the configurations, methods, etc. shown in this embodiment may be different from the configurations, methods, etc. shown in other embodiments. They can be used in appropriate combinations.

[0158] (Embodiment 3) In this embodiment mode, an OS transistor applicable to the semiconductor device described in the above embodiment mode will be described. An example of the configuration of the data will be described below.

[0159] <Example of transistor structure> 17A to 17C show an example of a transistor, which is an OS transistor. 17A is a cross-sectional view of the transistor 500 in the channel length direction. 17B is a cross-sectional view of the transistor 500 in the channel width direction.

[0160] The transistor 500 is a transistor having a metal oxide in a channel formation region (OS transistor). The transistor 500 is a transistor that can withstand high temperatures up to 200°C. It has excellent switching characteristics, and is therefore highly reliable even in high temperature environments. In addition, the off-state current can be reduced. Therefore, it is possible to provide a semiconductor device that consumes less power even in a high-temperature environment. do.

[0161] In the cross-sectional views shown in FIGS. 17(A) and 17(B), the insulator 512, the insulator 514, and the insulator The insulating material 512, the insulating material 514, and the insulating material 516 are stacked in this order. It is preferable that any of the bodies 516 is made of a material that has a barrier property against oxygen and hydrogen. .

[0162] For example, insulator 514 may be configured to provide a layer of insulating material, such as ... material that provides transistor 500, e.g., from an underlying substrate. It is preferable to use a film that has a barrier property to prevent hydrogen and impurities from diffusing into the region where the .

[0163] As an example of a film with barrier properties against hydrogen, silicon nitride formed by CVD is used. In addition, as a film having a barrier property against hydrogen, for example, an insulator 51 For 4, metal oxides such as aluminum oxide, hafnium oxide, and tantalum oxide can be used. It is preferable that:

[0164] In particular, aluminum oxide is highly resistant to oxygen and water, which can cause fluctuations in the electrical characteristics of transistors. It has a high blocking effect that prevents impurities such as oxygen and moisture from penetrating the membrane. Aluminum oxide is a material that can withstand hydrogen, moisture, and other chemicals during and after the transistor manufacturing process. This can prevent impurities from entering the transistor 500. This can suppress the release of oxygen from the oxide that makes up the transistor. It is suitable for use as a protective film for the substrate 500.

[0165] For example, the insulators 512 and 516 are made of a material with a relatively low dielectric constant. By using an insulating film between the wirings, the parasitic capacitance occurring between the wirings can be reduced. 12 and the insulator 516 may be a silicon oxide film, a silicon oxynitride film, or the like. This can be done.

[0166] Above the insulator 516 is the transistor 500 .

[0167] As shown in FIGS. 17A and 17B, the transistor 500 is disposed on an insulator 516. an insulator 520 disposed on the insulator 520; an insulator 522 disposed on the insulator 520; An insulator 524 disposed thereon, an oxide 530a disposed thereon, and an oxide The oxide 530b is disposed on the object 530a, and the oxide 530b is disposed on the object 530a, but is spaced apart from each other. Conductor 542a and conductor 542b are connected to each other. an insulator disposed on the conductive material 542 and having an opening formed therein overlapping the conductive material 542a and the conductive material 542b; 580, a conductor 560 disposed in the opening, oxide 530b, conductor 542a, and conductor The insulator 550 is disposed between the conductor 542b and the insulator 580 and the conductor 560. , oxide 530b, conductor 542a, conductor 542b, and insulator 580, and insulator 550 and an oxide 530c disposed therebetween.

[0168] As shown in FIGS. 17(A) and 17(B), the oxide 530a, the oxide 530b, the conductor 542a, and an insulator 544 is disposed between the conductor 542b and the insulator 580. 17(A) and 17(B), the conductor 560 is preferably an insulator 550. and a conductor 560a provided inside the conductor 560a so as to be embedded inside the conductor 560a. It is preferable that the conductive material 560b is provided with a conductive material 560b. Insulator 574 is disposed on insulator 580, conductor 560, and insulator 550. It is preferable that

[0169] In the following, the oxide 530a, the oxide 530b, and the oxide 530c will be collectively referred to as oxide 530a, oxide 530b, and oxide 530c. The conductor 542a and the conductor 542b are sometimes collectively referred to as oxide 530. It may also be referred to as conductor 542.

[0170] In the transistor 500, an oxide is formed in the region where the channel is formed and in the vicinity thereof. 5 shows a structure in which three layers of oxide 530a, oxide 530b, and oxide 530c are stacked. However, the present invention is not limited to this. For example, a single layer of oxide 530b, an oxide Two-layer structure of oxide 530b and oxide 530a, two-layer structure of oxide 530b and oxide 530c Alternatively, a stacked structure of four or more layers may be provided. Although the conductor 560 is shown as a two-layer laminate structure, the present invention is not limited to this. For example, the conductor 560 may have a single layer structure or a laminated structure of three or more layers. The transistor 500 shown in FIGS. 17A and 17B is just an example. However, the present invention is not limited to the above, and an appropriate transistor may be used depending on the circuit configuration and driving method.

[0171] Here, the conductor 560 functions as the gate electrode of the transistor, and the conductors 542a and and the conductor 542b function as a source electrode and a drain electrode, respectively. Thus, conductor 560 is inserted through the opening in insulator 580 and through conductors 542a and 542b. The conductor 560, the conductor 542a, and the conductor 542b are formed so as to be embedded in the region sandwiched between them. The placement of the conductor 542b is selected to be self-aligned with the opening of the insulator 580. In the transistor 500, the gate electrode is disposed between the source electrode and the drain electrode. Therefore, the conductor 560 can be arranged in a self-aligned manner without providing a margin for alignment. Since the transistor 500 can be formed without any gaps, the area occupied by the transistor 500 can be reduced. This allows for miniaturization and high integration of semiconductor devices.

[0172] Furthermore, the conductor 560 is self-aligned in the region between the conductors 542a and 542b. Since the conductor 560 is formed, the area where the conductor 560 overlaps with the conductor 542a or the conductor 542b is As a result, the conductor 560 does not have a gap between the conductor 542a and the conductor 542b. The parasitic capacitance formed can be reduced. This improves the scanning speed and provides high frequency characteristics.

[0173] The insulator 550 functions as a gate insulating film.

[0174] Here, the insulator 524 in contact with the oxide 530 has more oxygen than the stoichiometric composition. It is preferable to use an insulator that contains a large amount of oxygen. That is, the insulator 524 has an excess oxygen region. It is preferable that the insulator containing such excess oxygen is formed in the oxide 530. By providing the oxide 530 in contact with the oxide 530, oxygen vacancies in the oxide 530 are reduced, and the signal quality of the transistor 500 is improved. The reliability can be improved.

[0175] As an insulator having an excess oxygen region, specifically, an oxide in which a part of oxygen is released by heating is used. It is preferable to use oxide materials. Oxides that release oxygen when heated are called TDS (Th Thermal Desorption Spectroscopy (DSS) analysis revealed that the oxygen atoms The converted amount of oxygen desorption is 1.0 x 10 18 atoms / cm 3 or more, preferably 1.0 x10 19 atoms / cm 3 More preferably, 2.0 × 10 19 atoms / c m 3 or more, or 3.0 x 10 20 atoms / cm 3 The oxide film is as described above. The surface temperature of the film during the TDS analysis is 100°C or higher and 700°C or lower, or The temperature is preferably in the range of 00°C or higher and 400°C or lower.

[0176] Also, if the insulator 524 has an excess oxygen region, the insulator 522 may be oxygen-rich (e.g., It has the function of suppressing the diffusion of oxygen atoms, oxygen molecules, etc. (the oxygen is less likely to permeate) It is preferable that:

[0177] The insulator 522 has a function of suppressing the diffusion of oxygen and impurities, and the oxide 530 The oxygen contained therein is preferable because it does not diffuse to the insulator 520 side.

[0178] The insulator 522 may be, for example, aluminum oxide, hafnium oxide, tantalum oxide, or zinc oxide. lead zirconate titanate (PZT), strontium titanate (SrTiO3 ) or (Ba,Sr)TiO3 (BST), which are so-called high-k materials It is preferable to use the body in a single layer or a multilayer structure. As this progresses, problems such as leakage current may occur due to the thinning of the gate insulating film. By using a high-k material as an insulator that functions as a gate insulating film, This makes it possible to reduce the gate potential during transistor operation.

[0179] In particular, it has the function of suppressing the diffusion of impurities and oxygen (the oxygen is less likely to permeate). a) Insulating materials containing oxides of one or both of aluminum and hafnium It is recommended to use an insulator containing oxides of either or both aluminum and hafnium. The oxides include aluminum oxide, hafnium oxide, aluminum and hafnium. It is preferable to use oxide (hafnium aluminate) or the like. When the insulator 522 is formed by the oxide 530, the insulator 522 is resistant to oxygen release from the oxide 530 and to The layer serves to prevent impurities such as hydrogen from entering the oxide 530 from the periphery of the transistor 500. It works like this.

[0180] Alternatively, for example, aluminum oxide, bismuth oxide, germanium oxide, or the like may be added to these insulators. um, niobium oxide, silicon oxide, titanium oxide, tungsten oxide, yttrium oxide, Zirconium oxide may be added, or these insulators may be nitrided. Silicon oxide, silicon oxynitride or silicon nitride may be laminated on the insulator. .

[0181] The insulator 520 is preferably thermally stable. For example, silicon oxide and Silicon oxide nitride and silicon oxynitride are thermally stable and therefore suitable as high-k insulators and insulators. By combining with 20, it is possible to obtain a thermally stable laminated structure with a high relative dielectric constant. do.

[0182] The insulators 520, 522, and 524 each have a laminated structure of two or more layers. In this case, the laminated structure is not limited to the same material, but may be made of different materials. It may have a laminated structure.

[0183] The transistor 500 includes an oxide 530 including a channel formation region, and an oxide semiconductor It is preferable to use a functional metal oxide. For example, the oxide 530 is In-M- Zn oxide (element M is aluminum, gallium, yttrium, copper, vanadium, beryl Sodium, boron, titanium, iron, nickel, germanium, zirconium, molybdenum, la tantalum, tungsten, or magnesium It is preferable to use a metal oxide such as one or more selected from the group consisting of aluminum, etc. The material 530 may be an In-Ga oxide or an In-Zn oxide.

[0184] The metal oxide that functions as the channel forming region in the oxide 530 is a band gap metal oxide. It is preferable to use a material with a peak voltage of 2 eV or more, preferably 2.5 eV or more. By using a metal oxide with a wide band gap, the off-state current of a transistor can be reduced. It is possible.

[0185] The oxide 530 has an oxide 530a under the oxide 530b, so that the oxide 530a The diffusion of impurities from structures formed below the oxide 530b can be suppressed. In addition, by having the oxide 530c on the oxide 530b, the oxide 530c can be formed. Therefore, the diffusion of impurities from the structure formed above into the oxide 530b can be suppressed. do.

[0186] The oxide 530 has a layered structure made of oxides with different atomic ratios of metal atoms. Specifically, in the metal oxide used for the oxide 530a, the constituent elements are preferably The atomic ratio of element M in the oxide 530b is It is preferable that the atomic ratio of the metal oxide used for the oxide 530a is larger than that of the element M. In the oxide 530b, the atomic ratio of the element M to In is It is preferable that the atomic ratio of element M to In is larger than that of element M. In the metal oxide used, the atomic ratio of In to the element M is It is preferable that the atomic ratio of In to the element M in the metal oxide is larger than that of In. Oxide 530c is a metal oxide that can be used for oxide 530a or oxide 530b. Things can be used.

[0187] The energy of the conduction band minimum of the oxide 530a and the oxide 530c is It is preferable that the energy of the conduction band minimum of 0b is higher than that of the oxide. The electron affinity of the oxide 530a and the oxide 530c is smaller than the electron affinity of the oxide 530b. It is preferable that

[0188] Here, at the junctions of oxide 530a, oxide 530b, and oxide 530c, The energy level of the conduction band minimum changes gradually. The energy level of the conduction band minimum at the junction of the oxide 530b and the oxide 530c is It can also be said that the oxide layer is continuously changed or continuously bonded. At the interface between oxide 530a and oxide 530b, and at the interface between oxide 530b and oxide 530c In this case, the defect level density of the mixed layer formed in the step (b) is preferably reduced.

[0189] Specifically, oxide 530a and oxide 530b, and oxide 530b and oxide 530c are By having a common element other than oxygen (as the main component), a mixed layer with low defect level density is formed. For example, when the oxide 530b is an In-Ga-Zn oxide, the oxide 530a and oxide 530c, In-Ga-Zn oxide, Ga-Zn oxide, oxide Gallium nitride or the like may be used.

[0190] At this time, the main path of the carriers is the oxide 530b. By configuring 30c as described above, the interface between oxide 530a and oxide 530b and the oxide This can reduce the defect state density at the interface between the oxide 530b and the nitride 530c. Therefore, the influence of interface scattering on carrier conduction is reduced, and the transistor 500 has high A large on-current can be obtained.

[0191] On the oxide 530b, a conductor 542 is formed, which functions as a source electrode and a drain electrode. (conductor 542a and conductor 542b) are provided. Aluminum, chromium, copper, silver, gold, platinum, tantalum, nickel, titanium, molybdenum, tantalum Gusten, hafnium, vanadium, niobium, manganese, magnesium, zirconium, Choose from beryllium, indium, ruthenium, iridium, strontium, and lanthanum. or an alloy containing the above-mentioned metal elements or a combination of the above-mentioned metal elements. It is preferable to use an alloy of tantalum nitride, titanium nitride, tungsten nitride, etc. titanium and aluminum nitrides, tantalum and aluminum nitrides, and titanium oxides Ruthenium, ruthenium nitride, oxides containing strontium and ruthenium, lanthanum and nickel It is preferable to use oxides containing titanium. Nitrides containing tantalum and aluminum, nitrides containing tantalum and aluminum, ruthenium oxide , ruthenium nitride, oxides containing strontium and ruthenium, oxides containing lanthanum and nickel Oxides are conductive materials that are resistant to oxidation or that maintain conductivity even after absorbing oxygen. Therefore, it is preferable.

[0192] As shown in FIG. 17A, the oxide 530 is formed at the interface with the conductor 542 and its vicinity. In the second embodiment, a region 543 (region 543a and region 543b) is formed as a low resistance region. In this case, the region 543a functions as either a source region or a drain region. The region 543b functions as the other of the source region and the drain region. A channel forming region is formed in the region sandwiched between region 543a and region 543b.

[0193] By providing the conductor 542 so as to be in contact with the oxide 530, the oxygen concentration in the region 543 In addition, the metal contained in the conductor 542 and the oxide 53 In such a case, a metal compound layer containing the component 0 may be formed. The carrier density increases, and region 543 becomes a low resistance region.

[0194] The insulator 544 is provided to cover the conductor 542 and prevents oxidation of the conductor 542. At this time, the insulator 544 covers the side surface of the oxide 530 and is in contact with the insulator 524. It may be provided.

[0195] Insulator 544 includes hafnium, aluminum, gallium, yttrium, and zirconium. Sm, tungsten, titanium, tantalum, nickel, germanium, or magnesium A metal oxide containing one or more metals selected from the group consisting of fluorine, fluorine, arsenic ...

[0196] In particular, the insulator 544 may be an oxide of aluminum or hafnium or both. Insulators containing aluminum oxide, hafnium oxide, aluminum and hafnium It is preferable to use oxides containing hafnium (hafnium aluminate). Hafnium aluminate has higher heat resistance than hafnium oxide. In addition, the conductor 542 is preferably made of a material having oxidation resistance. When using a material that absorbs oxygen and whose conductivity does not decrease significantly, 544 is not an essential component and may be designed appropriately depending on the desired transistor characteristics.

[0197] The insulator 550 functions as a gate insulating film. The insulator 550 is preferably arranged in contact with the sides (top and side surfaces). For example, the thermal desorption spectroscopy (TD) S analysis), the amount of oxygen released in terms of oxygen atoms was 1.0 x 10 18 atoms / cm 3 or more, preferably 1.0 × 10 19 atoms / cm 3 More than or equal to 2.0, more preferably x10 19 atoms / cm 3 or more, or 3.0 x 10 20 atoms / cm 3 That's all The surface temperature of the film during the TDS analysis was 100°C or higher. The temperature range is preferably from 100°C to 700°C.

[0198] Specifically, silicon oxide having excess oxygen, silicon oxynitride, silicon nitride oxide, Silicon nitride, fluorine-doped silicon oxide, carbon-doped silicon oxide, carbon and Silicon oxide doped with nitrogen and silicon oxide having vacancies can be used. Silicon oxide and silicon oxynitride are preferred because they are stable to heat.

[0199] An insulator that releases oxygen when heated is used as the insulator 550, and is placed on the top surface of the oxide 530c. By providing the oxide 530b in contact with the insulator 550, the oxide 530c passes through the oxide 530b. In addition, oxygen can be effectively supplied to the channel formation region of the insulator 524. In addition, it is preferable that the concentration of impurities such as water or hydrogen in the insulator 550 is reduced. The thickness of the insulator 550 is preferably 1 nm or more and 20 nm or less.

[0200] In addition, in order to efficiently supply excess oxygen contained in the insulator 550 to the oxide 530, A metal oxide may be provided between the insulating material 550 and the conductor 560. It is preferable to suppress the diffusion of oxygen from the body 550 to the conductor 560. By providing a metal oxide, the diffusion of excess oxygen from the insulator 550 to the conductor 560 is suppressed. In other words, it is possible to suppress the decrease in the amount of excess oxygen supplied to the oxide 530. In addition, oxidation of the conductor 560 due to excess oxygen can be suppressed. Any material that can be used for the insulator 544 may be used.

[0201] The conductor 560 functioning as the gate electrode is shown as a two-layer structure in FIGS. However, it may have a single layer structure or a laminated structure of three or more layers.

[0202] The conductor 560a is a hydrogen atom, a hydrogen molecule, a water molecule, a nitrogen atom, a nitrogen molecule, or a nitrogen oxide molecule. (N2O, NO, NO2, etc.), conductive material with the function of suppressing the diffusion of impurities such as copper atoms It is preferable to use a material containing a small amount of oxygen (for example, oxygen atoms, oxygen molecules, etc.). It is preferable to use a conductive material that has the function of suppressing the diffusion of at least one of the conductors. Since 60a has the function of suppressing the diffusion of oxygen, the oxygen contained in the insulator 550 This can prevent the conductor 560b from being oxidized and the conductivity from decreasing. Examples of conductive materials that have the function of suppressing scattering include tantalum, tantalum nitride, and tantalum fluoride. It is preferable to use ruthenium or ruthenium oxide.

[0203] The conductor 560b is a conductive material mainly composed of tungsten, copper, or aluminum. In addition, since the conductor 560b also functions as a wiring, It is preferable to use a conductor with high conductivity, such as tungsten, copper, or aluminum. The conductor 560b can be made of a conductive material containing aluminum as a main component. For example, it may be a laminated structure of titanium, titanium nitride and the above conductive material. stomach.

[0204] The insulator 580 is provided on the conductor 542 via the insulator 544. Preferably, the insulator 580 has an excess oxygen region. For example, silicon oxide is used as the insulator 580. , silicon oxynitride, silicon nitride oxide, silicon nitride, fluorine-doped silicon oxide , carbon-doped silicon oxide, carbon- and nitrogen-doped silicon oxide, vacancy-containing silicon oxide It is preferable that the insulating layer contains silicon oxide or resin. In particular, silicon oxide and oxide Silicon nitride is preferred because it is thermally stable. In particular, silicon oxide and vacant oxide are preferred. Silicon dioxide is preferred because it allows for easy formation of an excess oxygen region in a subsequent step.

[0205] The insulator 580 preferably has an excess oxygen region. Oxygen is released upon heating. By providing the insulator 580 in contact with the oxide 530c, the oxygen in the insulator 580 is oxidized. The oxide 530 can be efficiently supplied through the insulator 530c. It is preferable that the concentration of impurities such as water or hydrogen in 80 is reduced.

[0206] The opening in the insulator 580 is formed to overlap the region between the conductor 542a and the conductor 542b. As a result, the conductor 560 is connected to the opening of the insulator 580 and the conductor 542a. It is formed so as to be embedded in the region sandwiched between the bodies 542b.

[0207] In miniaturizing semiconductor devices, it is required to shorten the gate length. It is necessary to prevent the conductivity of the conductor 60 from decreasing. In this embodiment, the conductor 560 may have a shape with a high aspect ratio. The conductor 560 is provided so as to be embedded in the opening of the insulator 580. Even a shape with a high ratio can be formed without causing the conductor 560 to collapse during the process. Cut.

[0208] The insulator 574 is disposed on the top surface of the insulator 580, the top surface of the conductor 560, and the top surface of the insulator 550. The insulator 574 is preferably provided in contact with the surface. Thus, an excess oxygen region can be provided in the insulator 550 and the insulator 580. From this excess oxygen region, oxygen can be supplied into the oxide 530 .

[0209] For example, the insulator 574 may be hafnium, aluminum, gallium, yttrium, Zirconium, tungsten, titanium, tantalum, nickel, germanium, or magnesium It is possible to use a metal oxide containing one or more metals selected from the group consisting of cadmium, cadmium, and sulphur. Cut.

[0210] In particular, aluminum oxide has a high barrier property and is a thin film of 0.5 nm to 3.0 nm. Therefore, the diffusion of hydrogen and nitrogen can be suppressed even if sputtering is performed. The aluminum oxide film formed by this method is a source of oxygen and also a barrier for impurities such as hydrogen. It can also function as a film.

[0211] In addition, it is preferable to provide an insulator 581 that functions as an interlayer film over the insulator 574. The insulator 581, like the insulator 524, has a low impurity concentration such as water or hydrogen in the film. is preferably reduced.

[0212] Also, the insulating material 581, the insulating material 574, the insulating material 580, and the insulating material 544 are formed. The conductor 540a and the conductor 540b are placed in the opening. The conductors 540a and 540b are provided opposite each other with the conductor 560 in between. b has a function as a plug or wiring that connects to the transistor 500 .

[0213] By using this structure, a semiconductor device using a transistor having an oxide semiconductor This makes it possible to suppress fluctuations in electrical characteristics and improve reliability. A transistor including an oxide semiconductor and having a large on-state current can be provided. It is possible to provide a transistor including an oxide semiconductor with low current. A semiconductor device having an oxide semiconductor can be provided. In a semiconductor device using a transistor, miniaturization or high integration can be achieved.

[0214] Note that the transistor 500 of the semiconductor device described in this embodiment is not limited to the above structure. The following describes examples of structures that can be used for the transistor 500. .

[0215] <Transistor structure example 1> An example of the structure of the transistor 510A will be described with reference to FIGS. 18(A), (B), and (C). FIG. 18(A) is a top view of the transistor 510A. FIG. 18(B) is a top view of the transistor 510A. FIG. 18(C) is a cross-sectional view of the portion indicated by the dashed line L1-L2 in FIG. 18A is a cross-sectional view of the portion indicated by the chain line W1-W2. For clarity, some elements are omitted from the illustration.

[0216] 18(A), (B), and (C), a transistor 510A and a layer functioning as an interlayer film are shown. Insulators 511, 512, 514, 516, 580, and 582, and insulator 584. Also shown are transistors 510A and 510B. The conductors 546 (conductors 546a and 546b) functioning as contact plugs 6b).

[0217] The transistor 510A includes a conductor 560 (conductor 560a, and conductor 560b), an insulator 550 functioning as a gate insulating film, and a channel formed The oxide 530 has regions formed therein (oxide 530a, oxide 530b, and oxide 530c). 30c), a conductor 542a serving as either a source or a drain, and a The drain electrode 542 has a conductor 542b that functions as the other drain electrode, and an insulator 574.

[0218] In addition, in the transistor 510A shown in FIGS. 18(A), (B), and (C), oxide 5 30c, an insulator 550, and a conductor 560 are inserted into an opening in the insulator 580. The oxide 530c, the insulator 550, and the conductor 574 are disposed between the oxide 530c and the insulator 550. 560 is disposed between the conductor 542a and the conductor 542b.

[0219] The insulators 511 and 512 function as interlayer films.

[0220] The interlayer film may be silicon oxide, silicon oxynitride, silicon nitride oxide, or aluminum oxide. um, hafnium oxide, tantalum oxide, zirconium oxide, lead zirconate titanate (PZ T), strontium titanate (SrTiO3) or (Ba,Sr)TiO3 (BST ) can be used as a single layer or a laminate. For example, aluminum oxide, bismuth oxide, germanium oxide, niobium oxide, silicon oxide, Titanium oxide, tungsten oxide, yttrium oxide, and zirconium oxide may be added. Alternatively, these insulators may be nitrided. Silicon or silicon nitride may also be used in a laminated form.

[0221] For example, the insulator 511 prevents impurities such as water or hydrogen from entering the transistor 51 from the substrate side. It is preferable that the insulating film functions as a barrier film that prevents the inclusion of OA. The body 511 has a function of suppressing the diffusion of impurities such as hydrogen atoms, hydrogen molecules, water molecules, and copper atoms. It is preferable to use an insulating material that has a high conductivity (the impurities are less likely to penetrate). It has the function of suppressing the diffusion of oxygen (for example, at least one of oxygen atoms, oxygen molecules, etc.) It is preferable to use an insulating material that is difficult for oxygen to permeate. Aluminum oxide or silicon nitride may be used as 511. Impurities such as hydrogen and water diffuse from the substrate side of the insulator 511 to the transistor 510A side. This can suppress the

[0222] For example, the insulator 512 preferably has a lower dielectric constant than the insulator 511. By using a low-cost material for the interlayer film, the parasitic capacitance occurring between wirings can be reduced.

[0223] In transistor 510A, conductor 560 may function as a gate electrode. do.

[0224] The insulators 514 and 516 are layers similar to the insulators 511 and 512. For example, the insulator 514 functions as a barrier film to prevent impurities such as water or hydrogen from entering the substrate. It is preferable that the film functions as a barrier film that prevents the metal oxide from entering the transistor 510A. This structure allows impurities such as hydrogen and water to pass through the insulator 514 from the substrate side to the transistor. 510A. It is preferable that the dielectric constant of the interlayer film is lower than that of the substrate 514. By using a material with a low dielectric constant as the interlayer film, The parasitic capacitance occurring between the wirings can be reduced.

[0225] Furthermore, the insulator 522 preferably has a barrier property. By having this, impurities such as hydrogen from the periphery of the transistor 510A to the transistor 510A can be prevented. It functions as a layer that suppresses the inclusion of impurities.

[0226] The insulator 522 may be, for example, aluminum oxide, hafnium oxide, aluminum and hafnium oxide. Oxides containing hafnium (hafnium aluminate), tantalum oxide, zirconium oxide, Lead zirconate titanate (PZT), strontium titanate (SrTiO3) or (B Insulators containing so-called high-k materials such as a,Sr)TiO3 (BST) are deposited as single layers or As transistors become smaller and more highly integrated, Thinning the gate insulating film can cause problems such as leakage current. By using high-k materials as insulators that function as a transistor, the physical thickness can be maintained. This makes it possible to reduce the gate potential during start operation.

[0227] For example, the insulator 521 is preferably thermally stable, e.g., silicon oxide. Silicon oxynitride is a thermally stable material and is therefore a good choice for insulating and insulating high-k materials. By combining it with 522, it is possible to create a thermally stable laminated structure with a high dielectric constant. Cut.

[0228] The oxide 530 having a region that functions as a channel formation region is formed by an oxide 530a and an oxide The oxide 530b is on the oxide 530a, and the oxide 530c is on the oxide 530b. By having the oxide 530a under the oxide 530b, the oxide 530b is formed below the oxide 530a. The diffusion of impurities from the oxide 530b to the oxide 530b can be suppressed. By having oxide 530c on object 530b, the oxide 530c is formed above the oxide 530c. The diffusion of impurities from the structure to the oxide 530b can be suppressed. As the material, an oxide semiconductor, which is one of the above-mentioned metal oxides, can be used.

[0229] The oxide 530c is formed in the opening of the insulator 580 through the insulator 574. When the insulator 574 has a barrier property, the insulating material 574 is preferably provided with a barrier layer. This can prevent impurities from diffusing into the oxide 530.

[0230] One of the conductors 542 functions as a source electrode and the other functions as a drain electrode. .

[0231] The conductor 542a and the conductor 542b are made of aluminum, titanium, chromium, nickel, Copper, yttrium, zirconium, molybdenum, silver, tantalum, or tungsten, etc. In particular, tantalum nitride, etc. The metal nitride film has barrier properties against hydrogen and oxygen, and is highly resistant to oxidation. ,preferable.

[0232] Although a single layer structure is shown in FIGS. 18(A), (B), and (C), a laminated structure of two or more layers may also be used. For example, a tantalum nitride film and a tungsten film may be laminated. A tungsten film and an aluminum film may be laminated. Two-layer structure: a copper film laminated on a copper-magnesium-aluminum alloy film , a two-layer structure in which a copper film is laminated on a titanium film, and a two-layer structure in which a copper film is laminated on a tungsten film. You may do so.

[0233] Also, a titanium film or titanium nitride film and an aluminum film overlaid on the titanium film or titanium nitride film are used. An aluminum film or a copper film is laminated, and a titanium film or a titanium nitride film is further formed thereon. A three-layer structure consisting of a molybdenum film or molybdenum nitride film and a molybdenum film or molybdenum nitride film. An aluminum or copper film is layered on top of the molybdenum film, and then a molybdenum or There are three-layer structures in which indium oxide, tin oxide or molybdenum nitride are formed. Alternatively, a transparent conductive material containing zinc oxide may be used.

[0234] A barrier layer may be provided on the conductor 542. The barrier layer is resistant to oxygen or hydrogen. It is preferable to use a substance having a barrier property against the insulator 574. During film formation, the conductor 542 can be prevented from being oxidized.

[0235] The barrier layer may be made of, for example, a metal oxide, particularly aluminum oxide, Using insulating films such as hafnium oxide and gallium oxide that have barrier properties against oxygen and hydrogen It is also preferable to use silicon nitride formed by the CVD method.

[0236] The barrier layer can broaden the range of material options for the conductor 542. For example, The conductor 542 is made of tungsten or aluminum, which has low oxidation resistance but high conductivity. In addition, for example, a conductive material that is easy to form a film or process can be used. You can be there.

[0237] The insulator 550 functions as a gate insulating film. In the opening, an oxide 530c and an insulator 574 are preferably provided. It's nice.

[0238] As transistors become smaller and more highly integrated, the gate insulating film becomes thinner, which reduces the lead In this case, the insulator 550 may have a laminated structure. The insulator that functions as the gate insulating film is made of high-k material and thermally stable material. By using a laminated structure with a material, the gate potential during transistor operation can be controlled while maintaining the physical film thickness. It is also possible to achieve a thermally stable laminated structure with a high relative dielectric constant. .

[0239] The conductor 560 functioning as a gate electrode is formed by a conductor 560a and a The conductor 560a includes a hydrogen atom, a hydrogen molecule, a water molecule, a copper atom, etc. It is preferable to use a conductive material that has the function of suppressing the diffusion of impurities. Has the function of suppressing the diffusion of oxygen (for example, at least one of oxygen atoms, oxygen molecules, etc.) It is preferable to use a conductive material. The function of suppressing diffusion is to suppress the diffusion of either one or all of the above impurities or the above oxygen. The function is to suppress the above.

[0240] The conductor 560a has a function of suppressing the diffusion of oxygen, and therefore the material of the conductor 560b In other words, by having the conductor 560a, the conductor 560 The oxidation of b is suppressed, and the decrease in electrical conductivity can be prevented.

[0241] Examples of conductive materials that have the function of suppressing oxygen diffusion include tantalum and tantalum nitride. It is preferable to use ruthenium, ruthenium oxide, or the like. As Oa, an oxide semiconductor that can be used as the oxide 530 can be used. In this case, the conductor 560b is formed by sputtering, so that the electric potential of the conductor 560a is reduced. This is called OC (Oxide Conductor). The electrode can be called a ctor electrode.

[0242] The conductor 560b is made of a conductive material mainly composed of tungsten, copper, or aluminum. In addition, since the conductor 560 functions as a wiring, it is preferable to use a material having high conductivity. It is preferable to use a conductor that is strong enough to withstand the heat. For example, tungsten, copper, or aluminum may be used as the main material. The conductor 560b may have a layered structure. For example, a laminate of titanium, titanium nitride and the above conductive material may be used.

[0243] An insulator 574 is disposed between the insulator 580 and the transistor 510A. 4 is an insulating material that has the function of suppressing the diffusion of impurities such as water or hydrogen, and oxygen. For example, aluminum oxide or hafnium oxide is preferably used. In addition, other examples include magnesium oxide, gallium oxide, germanium oxide, Yttrium oxide, zirconium oxide, lanthanum oxide, neodymium oxide or tantalum oxide Metal oxides such as silicon nitride oxide or silicon nitride can be used.

[0244] By including the insulator 574, impurities such as water and hydrogen contained in the insulator 580 can be converted into an acid. The oxide 530c is prevented from diffusing into the oxide 530b through the insulator 550. In addition, the excess oxygen contained in the insulator 580 can prevent the conductor 560 from being oxidized. It is possible.

[0245] Insulators 580, 582, and 584 function as interlayer films.

[0246] The insulator 582, like the insulator 514, prevents impurities such as water or hydrogen from traversing the It is preferable that the insulating film functions as a barrier insulating film that prevents the metal from being mixed into the transistor 510A.

[0247] In addition, the insulators 580 and 584, like the insulator 516, are thicker than the insulator 582. By using a material with a low dielectric constant as the interlayer film, the This can reduce the parasitic capacitance.

[0248] Also, transistor 510A is connected to insulators 580, 582, and 584. Electrical connections to other structures may be made through plugs or wiring such as embedded conductors 546. good.

[0249] The material of the conductor 546 may be a metal material, an alloy material, a metal nitride material, or a gold material. Conductive materials such as metal oxide materials can be used in a single layer or in a laminated layer. It is preferable to use high-melting-point materials such as tungsten and molybdenum, which have both thermal and electrical conductivity. Alternatively, it is preferable to form the wiring board from a low-resistance conductive material such as aluminum or copper. By using a resistive conductive material, the wiring resistance can be reduced.

[0250] For example, the conductor 546 may be a material having barrier properties against hydrogen and oxygen. By using a layered structure of conductive materials such as tantalum nitride and highly conductive tungsten, It is possible to suppress the diffusion of impurities from the outside while maintaining the conductivity of the wiring. .

[0251] By having the above structure, a transistor including an oxide semiconductor and having a large on-state current can be provided. Alternatively, a semiconductor device having an oxide semiconductor with a low off-state current can be provided. A semiconductor device having a transistor can be provided. To provide a semiconductor device having stable electrical characteristics and improved reliability. can be done.

[0252] <Transistor structure example 2> An example of the structure of the transistor 510B will be described with reference to FIGS. 19(A), (B), and (C). FIG. 19(A) is a top view of the transistor 510B. FIG. 19(B) is a top view of the transistor 510B. 19(A) is a cross-sectional view of the portion indicated by the dashed line L1-L2 in FIG. 19(A) is a cross-sectional view of the portion indicated by the chain line W1-W2. For clarity, some elements are omitted from the illustration.

[0253] Transistor 510B is a modification of transistor 510A. To avoid confusion, differences from transistor 510A will be mainly described.

[0254] Transistor 510B has conductors 542 (conductors 542a and 542b) and , the oxide 530c, the insulator 550, and the conductor 560 overlap each other. With this structure, a transistor with a high on-state current can be provided. Therefore, a highly efficient transistor can be provided.

[0255] The conductor 560 functioning as a gate electrode is formed by a conductor 560a and a The conductor 560a includes a hydrogen atom, a hydrogen molecule, a water molecule, a copper atom, etc. It is preferable to use a conductive material that has the function of suppressing the diffusion of impurities. Has the function of suppressing the diffusion of oxygen (for example, at least one of oxygen atoms, oxygen molecules, etc.) It is preferable to use a conductive material.

[0256] The conductor 560a has a function of suppressing the diffusion of oxygen, and therefore the material of the conductor 560b In other words, by having the conductor 560a, the conductor 560 The oxidation of b is suppressed, and the decrease in electrical conductivity can be prevented.

[0257] In addition, the top and side surfaces of the conductor 560, the side surfaces of the insulator 550, and the oxide 530c It is preferable to provide an insulator 574 so as to cover the side surface. When an insulating material is used that has the function of suppressing the diffusion of impurities such as hydrogen and oxygen, For example, it is preferable to use aluminum oxide or hafnium oxide. Other examples include magnesium oxide, gallium oxide, germanium oxide, and yttrium oxide. metals such as sodium, zirconium oxide, lanthanum oxide, neodymium oxide or tantalum oxide Oxide, silicon nitride oxide, silicon nitride, or the like can be used.

[0258] By providing the insulator 574, oxidation of the conductor 560 can be suppressed. By providing the insulator 574, impurities such as water and hydrogen contained in the insulator 580 are absorbed into the transistor. This can prevent diffusion to resistor 510B.

[0259] In addition, an insulator 576 (insulator) having a barrier property is provided between the conductor 546 and the insulator 580. By providing the insulator 576, The oxygen in the insulator 580 reacts with the conductor 546, and the conductor 546 is prevented from being oxidized. This can be done.

[0260] In addition, by providing an insulator 576 having a barrier property, the conductive material used for the plug and wiring can be For example, the conductor 546 can be made of a material with oxygen-absorbing properties. While having high electrical conductivity, the use of metal materials provides a semiconductor device with low power consumption. Specifically, tungsten and aluminum have low oxidation resistance, but In addition, for example, a material that is easy to form a film or process can be used. A conductor may be used.

[0261] <Transistor structure example 3> An example of the structure of the transistor 510C will be described with reference to FIGS. 20(A), (B), and (C). FIG. 20(A) is a top view of transistor 510C. FIG. 20(B) is a top view of transistor 510C. FIG. 20(C) is a cross-sectional view of the portion indicated by the dashed line L1-L2 in FIG. 20(A). 20(A) is a cross-sectional view of the portion indicated by the chain line W1-W2. For clarity, some elements are omitted from the illustration.

[0262] Transistor 510C is a modification of transistor 510A. To avoid confusion, differences from transistor 510A will be mainly described.

[0263] The transistor 510C shown in FIGS. 20A, 20B, and 20C has a conductor 542a and A conductor 547a is disposed between the oxide 530b, and a conductor 542b is disposed between the oxide 530b. The conductor 547b is disposed on the conductor 542a (conductor 542b). The conductor 547a (conductor 547b) extends beyond the upper surface and the side surface on the conductor 560 side, and The conductor 547 has a region that contacts the upper surface of the conductor 542. Furthermore, the thickness of the conductor 547 is at least It is preferably thicker than the conductive material 542 .

[0264] The transistor 510C shown in FIGS. 20(A), (B), and (C) has the above-described configuration. conductor 542 is closer to conductor 560 than transistor 510A. Alternatively, the end of the conductor 542a and the end of the conductor 542b may be connected to the conductor The body 560 can be overlapped, which effectively forms the channel of the transistor 510C. This can shorten the length and improve the on-state current and frequency characteristics.

[0265] In addition, the conductor 547a (conductor 547b) overlaps with the conductor 542a (conductor 542b). By adopting such a configuration, the conductor 546a (the conductor In the etching to form the opening in which the conductor 547a (conductor 546b) is embedded, 47b) acts as a stopper to prevent over-etching of oxide 530b. It is possible.

[0266] 20(A), (B), and (C), the transistor 510C has an insulator 54 The insulator 544 may be made of water or other suitable material. Impurities such as hydrogen or excess oxygen are mixed into the transistor 510C from the insulator 580 side. It is preferable that the insulator 545 functions as a barrier insulating film that suppresses the penetration of Insulators that can be used for the insulator 544 can be used. Examples of the nitride include aluminum nitride, aluminum titanium nitride, titanium nitride, and silicon nitride. Nitride insulators such as silicon or silicon oxynitride may also be used.

[0267] <Transistor structure example 4> An example of the structure of the transistor 510D will be described with reference to FIGS. 21(A), (B), and (C). FIG. 21(A) is a top view of the transistor 510D. FIG. 21(B) is a top view of the transistor 510D. FIG. 21(C) is a cross-sectional view of the portion indicated by the dashed line L1-L2 in FIG. 21(A). 21(A) is a cross-sectional view of the portion indicated by the chain line W1-W2. For clarity, some elements are omitted from the illustration.

[0268] Transistor 510D is a variation of the transistor described above. To prevent this, differences from the above transistor will be mainly described.

[0269] 21A to 21C, the oxide 530c has an insulator 550 thereon, and the insulator 550 A metal oxide 552 is provided on the metal oxide 552. A conductor 560 is provided on the metal oxide 552. An insulator 570 is provided on the body 560. An insulator 571 is provided on the insulator 570.

[0270] The metal oxide 552 preferably has a function of suppressing oxygen diffusion. By providing a metal oxide 552 between the conductive material 560 and the conductive material 560, which suppresses the diffusion of oxygen, The diffusion of oxygen into the dielectric 560 is suppressed. In other words, the amount of oxygen supplied to the oxide 530 is reduced. In addition, oxidation of the conductor 560 by oxygen can be suppressed. .

[0271] The metal oxide 552 may function as a part of the gate. The oxide semiconductor that can be used as the material 530 is used as the metal oxide 552. In this case, the conductor 560 is formed by sputtering, and the metal oxide 5 The electrical resistance of 52 can be reduced to make it a conductive layer. The electrode can be called a conductor.

[0272] The metal oxide 552 may also function as a part of the gate insulating film. Therefore, when silicon oxide or silicon oxynitride is used for the insulator 550, the metal oxide The material 552 is preferably a metal oxide, which is a high-k material having a high dielectric constant. This laminated structure is stable against heat and has a high dielectric constant. Therefore, the gate voltage applied during transistor operation can be adjusted while maintaining the physical film thickness. In addition, the equivalent oxide thickness ( It is possible to reduce the thickness of the EOT.

[0273] In the transistor 510D, the metal oxide 552 is shown as a single layer, but it may be a stack of two or more layers. For example, a metal oxide that functions as a part of the gate electrode and a gate insulating film may be used. A metal oxide that functions as part of the film may be laminated.

[0274] When the metal oxide 552 functions as a gate electrode, It is possible to improve the on-current of transistor 510D without weakening the influence of these electric fields. Alternatively, when it functions as a gate insulating film, the insulating film 550 and the metal oxide 55 2, the physical thickness of the conductor 560 and the oxide 530 are kept at a distance from each other. The leakage current between the conductor 560 and the oxide 530 can be suppressed. By providing a stacked structure of the conductor 550 and the metal oxide 552, the conductor 560 and the oxide The physical distance between the conductor 560 and the oxide 530, and the electric field strength acting on the oxide 530 from the conductor 560 are , and can be easily adjusted appropriately.

[0275] Specifically, by reducing the resistance of an oxide semiconductor that can be used for the oxide 530, Metal oxide 552 can be used. Alternatively, hafnium, aluminum, gallium Sm, yttrium, zirconium, tungsten, titanium, tantalum, nickel, gel Metals containing one or more of the following: ammonium, magnesium, etc. An oxide can be used.

[0276] In particular, the insulating layer contains oxides of either or both of aluminum and hafnium. , aluminum oxide, hafnium oxide, oxides containing aluminum and hafnium (hafnium It is preferable to use hafnium aluminate. Therefore, the heat resistance of the hafnium oxide film is higher than that of the hafnium oxide film. It is preferable because it is difficult to crystallize. Note that the metal oxide 552 is not an essential component. It may be designed appropriately depending on the transistor characteristics.

[0277] The insulator 570 has a function of suppressing the permeation of impurities such as water or hydrogen, and oxygen. For example, aluminum oxide or hafnium oxide can be used. This prevents the conductor 560 from being damaged by oxygen from above the insulator 570. In addition, the insulator 570 can prevent water or hydrogen from flowing from above the insulator 570. Impurities such as ions may be mixed into the oxide 230 via the conductor 560 and the insulator 550. This can suppress the above.

[0278] The insulator 571 functions as a hard mask. When processing 60, the side of the conductor 560 is approximately perpendicular, specifically, the side of the conductor 560 and the substrate The angle formed by the plate surface is 75 degrees or more and 100 degrees or less, preferably 80 degrees or more and 95 degrees or less. This can be done.

[0279] The insulator 571 has a function of suppressing the permeation of impurities such as water or hydrogen, and oxygen. By using an insulating material having the above structure, the insulating material may also function as a barrier layer. In this case, the insulator 570 may not be provided.

[0280] The insulator 571 is used as a hard mask to form the insulator 570, the conductor 560, and the metal oxide 552, insulator 550, and oxide 530c are selectively removed to remove these The side surfaces of the oxide 530b can be made substantially flush with each other, and part of the surface of the oxide 530b can be exposed.

[0281] Transistor 510D also has regions 531a and 531b on a portion of the exposed oxide 530b surface. and region 531b. One of region 531a or region 531b is used as a source region. one functions as a drain region, and the other functions as a drain region.

[0282] The regions 531a and 531b can be formed by, for example, ion implantation or ion doping. The exposed oxide is then removed using a method such as plasma immersion ion implantation or plasma treatment. This can be achieved by introducing impurity elements such as phosphorus or boron into the surface of the oxide 530b. In this embodiment, the term "impurity element" refers to an element other than the main component element. .

[0283] In addition, after exposing a part of the surface of the oxide 530b, a metal film is formed and then heat-treated. By this, the elements contained in the metal film are diffused into the oxide 530b, and the regions 531a and A region 531b can also be formed.

[0284] The region of the oxide 530b into which the impurity element is introduced has a reduced electrical resistivity. The regions 531a and 531b may be referred to as "impurity regions" or "low resistance regions." do.

[0285] By using the insulator 571 and / or the conductor 560 as a mask, the region 531a The region 531b can be formed in a self-aligned manner. Therefore, the region 531a and / or the region 531b do not overlap with the conductor 560, and the parasitic capacitance is reduced. In addition, the channel forming region and the source / drain region (region 531a and No offset region is formed between region 531a and region 531b. By forming 1b in a self-aligned manner, the on-current is increased and the threshold This allows for reduction of the voltage threshold and improvement of the operating frequency.

[0286] In order to further reduce the off-state current, an off-state current is formed between the channel forming region and the source / drain region. An offset region is a region having a high electrical resistivity, and The offset region is a region where the introduction of the impurity element is not performed. This can be achieved by introducing the impurity element described above after the formation of the insulator 5. The insulating layer 75 functions as a mask in the same manner as the insulating layer 571. Impurity elements are not introduced into the region overlapping with the body 575, and the electrical resistivity of the region remains high. It is possible.

[0287] The transistor 510D also includes an insulator 570, a conductor 560, a metal oxide 552, ... The insulating layer 575 is disposed on the side of the insulating layer 550 and the oxide 530c. It is preferable to use an insulator with a low dielectric constant, such as silicon oxide, silicon oxynitride, Silicon oxynitride, silicon nitride, silicon oxide with fluorine, silicon oxide with carbon silicon, carbon and nitrogen doped silicon oxide, silicon oxide with vacancies, or Resins are preferred. In particular, silicon oxide, silicon oxynitride, silicon nitride oxide, etc. In the latter process, if silicon oxide with vacancies is used as the insulator 575, In addition, silicon oxide and silicon oxynitride are preferable because they can easily form an excess oxygen region. Silicon is preferred because it is thermally stable. Insulator 575 also has the function of diffusing oxygen. It is preferred that the compound has the following structure:

[0288] Also, transistor 510D has insulator 575 and insulator 574 on oxide 530. The insulator 574 is preferably formed by sputtering. By using this method, it is possible to form an insulator film with few impurities such as water or hydrogen. For example, aluminum oxide may be used as the insulator 574.

[0289] In addition, the oxide film formed by the sputtering method may extract hydrogen from the structure on which the film is formed. Therefore, the insulator 574 absorbs hydrogen and water from the oxide 230 and the insulator 575. This can reduce the hydrogen concentration in the oxide 230 and the insulator 575.

[0290] <Transistor structure example 5> A structural example of the transistor 510E will be described with reference to FIGS. 22A to 22C. FIG. 22(A) is a top view of the transistor 510E. 22(A) is a cross-sectional view of the portion indicated by the dashed line L1-L2. 22(A) is a cross-sectional view of the portion indicated by W1-W2. For this reason, some elements are omitted in the illustration.

[0291] Transistor 510E is a modification of the transistor described above. To prevent this, differences from the above transistor will be mainly described.

[0292] 22A to 22C, the conductor 542 is not provided, and the exposed oxide 530 b has regions 531a and 531b on a part of the surface. One of the oxides 1b functions as a source region and the other functions as a drain region. An insulator 573 is provided between the object 530b and the insulator 574.

[0293] The area 531 (area 531a and area 531) shown in FIGS. 22(A) to 22(C) b) is a region where the following elements are added to the oxide 530b. The region 531 is, for example, This can be achieved by using a dummy gate.

[0294] Specifically, a dummy gate is provided on the oxide 530b, and the dummy gate is used as a mask. It is preferable to use the oxide 530b as a thin film and add an element that reduces the resistance of the oxide 530b. The element is added to the region not overlapping with the dummy gate, forming a region 531. The element is added by mass-separating the ionized source gas. ion implantation, which adds ionized source gas without mass separation; and ion doping, which adds ionized source gas without mass separation. method, plasma immersion ion implantation method, etc. can be used.

[0295] Representative elements that reduce the resistance of the oxide 530 include boron and phosphorus. In addition, hydrogen, carbon, nitrogen, fluorine, sulfur, chlorine, titanium, rare gases, etc. Representative examples of rare gases include helium, neon, argon, krypton, and xenon. The concentration of the element is measured by secondary ion mass spectrometry (SIMS). Measurement can be performed using methods such as ion mass spectrometry (Ion Mass Spectrometry).

[0296] In particular, boron and phosphorus are used in the manufacturing of amorphous silicon or low-temperature polysilicon. This is preferable because existing equipment can be used. Existing facilities can be repurposed. Capital investment can be reduced.

[0297] Next, an insulating film that will become an insulator 573 and a An insulating film to be the insulator 573 and an insulating film to be the insulator 574 may be formed. By laminating an insulating film that becomes the insulating layer 574, the region 531, the oxide 530c, and the insulating layer 574 are An overlapping area with the edge body 550 can be provided.

[0298] Specifically, after forming an insulating film to be the insulator 580 on the insulating film to be the insulator 574, The insulating film that will become the insulating film 580 is subjected to CMP (Chemical Mechanical Polishing). By performing a dummy gate etching process, a part of the insulating film that will become the insulator 580 is removed. Subsequently, when the dummy gate is removed, the insulator 57 in contact with the dummy gate is removed. Therefore, the side of the opening in the insulator 580 is covered with insulating material. The opening exposes the insulating layer 574 and the insulating layer 573. ... A part of the region 531 is exposed. Next, an oxide film that becomes oxide 530c is formed in the opening. After forming an insulating film to be the insulator 550 and a conductive film to be the conductor 560 in this order, The oxide film that becomes oxide 530c and the insulator 55 are formed by CMP processing or the like until 580 is exposed. 22(A) and the insulating film that will become the conductor 560 are removed. 22B.) to 22C can be formed.

[0299] Note that the insulators 573 and 574 are not essential components. It may be designed appropriately depending on the characteristics.

[0300] The transistors shown in FIGS. 22A to 22C can be formed by converting existing devices. Furthermore, since the conductor 542 is not provided, costs can be reduced.

[0301] Note that this embodiment mode may be implemented in appropriate combination with other embodiment modes described in this specification. It is possible.

[0302] (Fourth embodiment) In this embodiment mode, an electronic device in which the semiconductor device described in the above embodiment mode can be used is An example of the device will be described.

[0303] The semiconductor device according to one embodiment of the present invention can be mounted on various electronic devices. The semiconductor device according to one embodiment of the present invention is an electronic device that is expected to be handled in a high-temperature environment. It can be used as an IC for a control processor in an electronic device. In addition to vehicles and other moving objects, vacuum cleaners, microwave ovens, electric ovens, rice cookers, water heaters, induction cookers, etc. Cooking appliances, water dispensers, heating and cooling appliances including air conditioners, washing machines, dryers , audiovisual equipment, etc.

[0304] 23(A) to 23(D) show examples of electronic devices.

[0305] FIG. 23A is a diagram showing an automobile 5700 as an example of a moving object. The semiconductor device described controls devices such as sensors and actuators in the automobile 5700. This can be used in a control system.

[0306] 23(B) is a diagram showing an electric motorcycle 5800 as an example of a moving object. The semiconductor device described above is a device such as a sensor or actuator in the electric motorcycle 5800. It can be used in the control system that controls the equipment or the battery management system. can.

[0307] In the above description, automobiles and electric motorcycles are used as examples of moving objects. Moving objects are not limited to automobiles and electric motorcycles. For example, moving objects include trains and monorails. , ships, and aircraft (helicopters, unmanned aerial vehicles (drones), airplanes, rockets) The semiconductor device according to one embodiment of the present invention can be applied to these moving bodies. Cut.

[0308] FIG. 23(C) shows a microwave oven 5900 as an example of the electronic device. The semiconductor device described in the embodiment is a power device for passing current in a microwave oven 5900. It can be used in control ICs for controlling the above.

[0309] FIG. 23(D) shows an electric refrigerator-freezer 6000, which is an example of the electronic device. The semiconductor device described in the embodiment is a power supply for supplying current in the electric refrigerator-freezer 6000. It can be used in control ICs for controlling devices.

[0310] A semiconductor device according to one embodiment of the present invention operates with excellent reliability even in a high-temperature environment. This makes it possible to reduce power consumption. It is possible to achieve this.

[0311] Note that this embodiment mode may be implemented in appropriate combination with other embodiment modes described in this specification. It is possible.

[0312] (Notes regarding the present specification) The above-described embodiments and the respective components in the embodiments will be described below with additional notes.

[0313] The configurations shown in each embodiment may be appropriately combined with the configurations shown in other embodiments to realize the present invention. In addition, in one embodiment, multiple configuration examples may be shown. In this case, the configuration examples can be combined as appropriate.

[0314] It should be noted that the contents (or even a part of the contents) described in one embodiment may be used in the implementation of the embodiment. Another content (or part of the content) described in the form, and / or one or more other implementations The contents (or a part of the contents) described in the embodiments may be applied, combined, or replaced. You can do things like drawing.

[0315] The contents described in the embodiments are explained using various drawings in each embodiment. This refers to the content stated in the specification or the content stated using the text in the specification.

[0316] In addition, a drawing (or a part thereof) described in one embodiment may be replaced with another part of the drawing. , another figure (or a part thereof) described in the embodiment, and / or one or more By combining the figures (or a part thereof) described in other embodiments of the present invention, This allows for even more diagrams to be constructed.

[0317] In addition, in the block diagrams in this specification, components are classified by function and are independent of each other. However, in actual circuits, the components are divided into functional blocks. It is difficult to separate the functions into separate parts, and there are cases where multiple functions are involved in one circuit, or where a circuit is involved in multiple circuits. Therefore, the blocks in the block diagram may be The present invention is not limited to the components described above, and may be rephrased appropriately depending on the situation.

[0318] In addition, in the drawings, the size, layer thickness, and area are shown at arbitrary scales for the convenience of explanation. Therefore, the drawings are not necessarily limited to the scale. The drawings are merely schematic illustrations for the purpose of clarity, and are not limited to the shapes or values ​​shown in the drawings. fluctuations in signal, voltage, or current due to noise, or signal due to timing deviations These may include variations in signal, voltage, or current.

[0319] In this specification and the like, when describing the connection relationship of a transistor, "one side" (or first electrode, or first terminal), "the other side of the source or drain" (or second electrode The source and drain of a transistor are called the first terminal and the second terminal. This is because it varies depending on the structure or operating conditions of the transistor. The names of the source (drain) terminal and the source (drain) electrode, etc. Can be rephrased appropriately depending on the situation.

[0320] In addition, the terms "electrode" and "wiring" used in this specification and the like refer to these components functionally. This is not a limitation. For example, an "electrode" may be used as part of a "wiring." , and vice versa. Furthermore, the terms "electrode" and "wiring" may be used interchangeably with "electrodes" and "wiring." This also includes cases where the wiring is formed integrally.

[0321] In this specification and the like, the terms voltage and potential can be interchanged as appropriate. The potential difference from the reference potential. For example, the reference potential is the ground voltage (earth If we use the term "voltage", we can translate voltage into potential. Ground potential is not necessarily 0V. It does not necessarily mean that the potential is relative, and depending on the reference potential, The potential applied to wiring etc. may be changed.

[0322] In this specification, the terms "film" and "layer" are used in some cases or in other situations. For example, the term "conductive layer" can be used interchangeably with " It may be possible to change the term to "conductive film." In some cases, the term "insulating layer" can be changed to the term "insulating layer."

[0323] In this specification, a switch refers to a device that can be in a conducting state (ON state) or a non-conducting state (OFF state). It refers to a device that has the function of controlling whether or not current flows by entering a state where it is in a non-operating state. A switch is a device that has the function of selecting and switching a path through which a current flows.

[0324] In this specification and the like, the channel length is, for example, the length of a semiconductor the body (or the part of the semiconductor through which current flows when the transistor is on) and the gate The distance between the source and drain in the region where they overlap or where the channel is formed. It means separation.

[0325] In this specification, the channel width is, for example, the width of a semiconductor (or a transistor) when it is in an on state. The area where the gate electrode overlaps with the gate electrode (the area where current flows in the semiconductor when the gate electrode is in the non-transistor state), or the channel The length of the portion where the source and drain face each other in the region where the capacitor is formed. .

[0326] In this specification, "A and B are connected" does not mean that A and B are directly connected. In addition to those that are electrically connected, A and B are also included. Connected to means that there is an object that has some electrical effect between A and B. When this occurs, it refers to something that enables the transmission and reception of electrical signals between A and B. [Explanation of symbols]

[0327] IN1: terminal, IN2B: terminal, L1-L2: dashed line, T1: time, T2: time, T3 :Time, T4:Time, T5:Time, T6:Time, T7:Time, T8:Time, T11:Time , T12: Time, T13: Time, T14: Time, T21: Time, T22: Time, T23: Time, T24: Time, T25: Time, T26: Time, T27: Time, 100: Semiconductor device 100A: semiconductor device, 101: signal generating circuit, 102: logic circuit, 102B: logic circuit circuit, 102C: logic circuit, 102D: logic circuit, 102E: logic circuit, 111: transistor sta, 112: transistor, 113: transistor, 114: transistor, 115: Transistor, 121: transistor, 122: transistor, 123: transistor, 124: transistor, 125: transistor, 126: transistor, 127: transistor Transistor, 128: Transistor, 131: Transistor, 138: Transistor, 151 :Transistor, 165:Transistor, 201:Signal processing circuit, 202:Logic circuit, 2 02A: Logic circuit, 202B: Logic circuit, 202C: Logic circuit, 202D: Logic circuit, 2 03: Switch circuit, 203A: Switch circuit, 203B: Switch circuit, 203C: Switch circuit, 203D: switch circuit, 230: oxide, 300: transistor, 500 : transistor, 510A: transistor, 510B: transistor, 510C: transistor 510D: transistor, 510E: transistor, 511: insulator, 512: Insulator, 514: Insulator, 516: Insulator, 520: Insulator, 521: Insulator, 522: Insulator, 524: Insulator, 530: Oxide, 530a: Oxide, 530b: Oxide, 53 0c: oxide, 531: region, 531a: region, 531b: region, 540a: conductor, 5 40b: Conductor, 542: Conductor, 542a: Conductor, 542b: Conductor, 543: Area , 543a: region, 543b: region, 544: insulator, 545: insulator, 546: conductor , 546a: conductor, 546b: conductor, 547: conductor, 547a: conductor, 547b : conductor, 550: insulator, 552: metal oxide, 560: conductor, 560a: conductor, 560b: conductor, 570: insulator, 571: insulator, 573: insulator, 574: insulator , 575: insulator, 576: insulator, 576a: insulator, 576b: insulator, 580: insulator Insulators, 581: Insulators, 582: Insulators, 584: Insulators, 5700: Automobiles, 5800 : Electric motorcycle, 5900: Microwave oven, 6000: Electric refrigerator / freezer, 7000A: IC, 7000B: IC, 7001: Lead, 7002: Printed circuit board, 7003A: Circuit section, 7003B: Circuit section, 7004: Mounting board, 7031: OS transistor layer, 7032: Wiring layer, 7033: OS transistor layer

Claims

[Claim 1] a first input terminal and a second input terminal; a first output terminal and a second output terminal; a first wiring and a second wiring; first to fourth transistors, the first transistor has one of a source or a drain electrically connected to the first wiring, one of a gate or a back gate electrically connected to the first input terminal, and the other of the source or the drain and the other of the gate or the back gate electrically connected to the second output terminal; the second transistor has one of a source or a drain electrically connected to the first wiring, one of a gate or a back gate electrically connected to the second input terminal, and the other of the source or the drain and the other of the gate or the back gate electrically connected to the first output terminal; the third transistor has a gate and a back gate electrically connected to the first input terminal, one of a source and a drain electrically connected to the first output terminal, and the other of the source and the drain electrically connected to the second wiring; the fourth transistor has a gate and a back gate electrically connected to the second input terminal, one of a source and a drain electrically connected to the second output terminal, and the other of the source and the drain electrically connected to the second wiring.

Images