Semiconductor device

Abstract

To provide a semiconductor device in which a low power and stable operation can be achieved.SOLUTION: A logic circuit 102D comprising transistors 131-138 which have oxide semiconductors in channel formation regions is a two-wire type logic circuit having two inputs and two outputs. Each of transistors constituting a logic circuit has a gate and a back gate. An input terminal IN1 is electrically connected to one of a gate or a back gate of a transistor that is electrically connected to a wiring line VDDL which gives high power supply potential. An output terminal OUT is connected to the other of the gate or the back gate of the transistor that is electrically connected to the wiring line which gives high power supply potential. An output terminal OUTB is electrically connected to one of a source or a drain of a transistor that is electrically connected to a wiring line VSSL which gives low power supply potential. A gate or a back gate of the transistor that is electrically connected to the wiring line which gives the low power supply potential is electrically connected to input terminals IN2, IN1B, and 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 above. 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. Display devices, light-emitting devices, storage devices, electro-optical devices, power storage devices, control systems , a semiconductor circuit and an electronic device may include a semiconductor device. [Background technology]

[0004] A transistor in which the 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, the OS transistor has low power consumption. It is expected that this technology will be applied to logic circuits for low power consumption. For example, in Patent Document 1, A unipolar inverter circuit consisting of an OS transistor with a MOSFET 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 reduces power consumption. Problems such as increased force arise.

[0007] In addition, in transistors whose channel formation region is made of silicon (Si transistors), When the transistors that make up the logic circuits 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, making it difficult to maintain normal circuit operation. Problems will arise such that it will not be possible to do so.

[0008] In view of the above problems, one embodiment of the present invention is to provide a semiconductor device with excellent reliability. Another object of the present invention is to provide a semiconductor device that is excellent in reducing power consumption. One of the challenges we face is to

[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. Other issues can be extracted from the drawings, claims, etc. [Means for solving the problem]

[0010] One aspect of the present invention is a semiconductor device 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 the source or the drain electrically connected to the first wiring, and the gate or One of the gates is electrically connected to a 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 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 a second wiring.

[0011] One aspect of the present invention is a semiconductor device 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 semiconductor device, either the source or the drain is electrically connected to the first wiring, and either the gate or the backgate 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. and the second transistor has one of a source and a 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 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. and 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; The gate and the back gate of the transistor are electrically connected to the first input terminal, and the source or drain of the transistor is electrically connected to the first input terminal. One of the drains is electrically connected to the gate and the back gate of the fourth transistor, The other of the gate and drain of the sixth transistor is electrically connected to the third wiring. and the back gate is 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 wire The seventh transistor has a gate and a back gate electrically connected to the second input terminal. 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; 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 the drain is The semiconductor device is electrically connected to the wiring.

[0012] In one embodiment of the present invention, a first potential applied to the first wiring is a second potential applied to the second wiring. Semiconductor devices having a capacitance higher than 100 .mu.m are preferred.

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

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

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

[0017] One embodiment of the present invention is a semiconductor memory device including a plurality of switch circuits and a plurality of logic circuits, A first input terminal and a second input terminal, a first output terminal and a second output terminal, and first to third The first transistor has a source or drain. One of the gates or back gates is electrically connected to the first wiring, and one of the gates or back gates is connected to the first input The other of the source or drain and the gate or backgate are electrically connected to the terminal. the other end is electrically connected to the gate and the back gate of the second transistor, The transistor has one of the source and drain electrically connected to the second wiring. The other drain of the third transistor 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 of the first and second transistors 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, and the source or The other drain is electrically connected to the first output terminal. 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 also connected to the source or drain. 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 transistor has a gate and a back gate electrically connected to the second input terminal, and a source or a drain One of the inputs is electrically connected to the gate and the 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 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 embodiment of the present invention, a first potential applied to the first wiring is a second potential applied to the second wiring. Semiconductor devices having a capacitance higher than 100 .mu.m are preferred.

[0019] In one embodiment of the present invention, the first to eighth transistors each have a metal oxide 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 which is a transistor having a metal oxide in a channel forming region is preferred.

[0021] In one embodiment 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 is nice.

[0022] In one embodiment of the present invention, the metal oxide is at least In (indium) or Zn ( 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 the drawings. Effect of the Invention

[0025] One embodiment of the present invention can provide a semiconductor device with excellent reliability. 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 the drawings. [Brief description 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. [Diagram 2] 1A is a circuit diagram illustrating a configuration example of a semiconductor device, FIG. 1B is a timing chart, and FIG. 1C is a diagram showing circuit symbols. [Diagram 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. [Diagram 5]1A and 1B are circuit diagrams illustrating a configuration example of a semiconductor device. [Figure 6] 1A is a circuit diagram illustrating an example of a configuration of a semiconductor device, and FIG. 1B is a timing chart illustrating the same. [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 is a diagram showing circuit symbols, (B) is a diagram showing circuit symbols, (C) is a circuit diagram, and (D) is a timing chart illustrating an example of the configuration 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 is a circuit diagram illustrating an example of the configuration of a semiconductor device, and FIG. 1B is a diagram showing circuit symbols. [Figure 13] 1A is a circuit diagram illustrating an example of the configuration of a semiconductor device, and FIG. 1B is a diagram showing circuit symbols. [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 an example of a transistor structure. [Figure 18] 1A is a top view, FIG. 1B is a cross-sectional view, and FIG. 1C is a cross-sectional view illustrating an example of a transistor structure. [Figure 19] 1A is a top view, FIG. 1B is a cross-sectional view, and FIG. 1C is a cross-sectional view illustrating an example of a transistor structure. [Figure 20] 1A is a top view, FIG. 1B is a cross-sectional view, and FIG. 1C is a cross-sectional view illustrating an example of a transistor structure. [Figure 21]1A is a top view, FIG. 1B is a cross-sectional view, and FIG. 1C is a cross-sectional view illustrating an example of a transistor structure. [Figure 22] 1A is a top view, FIG. 1B is a cross-sectional view, and FIG. 1C is a cross-sectional view illustrating an example of a transistor structure. [Diagram 23] 1A to 1D are diagrams showing configuration examples of an electronic device. [Figure 24] Graph (A) and graph (B) illustrate the operation of the semiconductor device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] Hereinafter, the embodiments will be described with reference to the drawings. It is possible to carry out the invention in various forms without departing from the spirit and scope of the invention. It will be readily understood by 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 embodiment.

[0029] In this specification, the ordinal numbers "first," "second," and "third" refer to the components of the The above is added to avoid confusion, and does not limit the number of components. In addition, the order of the components is not limited. The element referred to as "first" in one embodiment may be used in another embodiment or in the claims. In addition, for example, the second component may be the component referred to in the present specification. A component referred to as "first" in one embodiment may be used in another embodiment, 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 denote elements that are formed simultaneously, and repeated explanations of such elements will be omitted. It may be omitted.

[0031] In the present specification and the like, 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. They are classified as follows.

[0032] For example, when a metal oxide is used for 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). A transistor having a metal oxide in a channel formation region is called an "oxide semiconductor transistor." Similarly, the above-mentioned “oxide semiconductor The "transistor used" is also a transistor having a metal oxide in a channel formation region.

[0033] (Embodiment 1) A 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 composed of Si transistors ( The signal generating circuit 101 uses a CMOS circuit to generate a sequential It can be constructed by appropriately designing the circuit and combinational circuit.

[0037] The logic circuit 102 has a circuit (illustrated as OS / Cir.) configured with OS transistors. The logic circuit 102 is a combinational circuit. The logic circuit 102 is a terminal that operates in response to an input signal and an inverted output signal. The output signal and the 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 silicon transistors, the electrical characteristics of transistors do not change much 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 The wiring VSSL to which a power supply potential VSS (for example, ground potential) is applied is illustrated.

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

[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 to the transistor, it can be classified as a depletion type (also called normally-on type). The transistor has the function of controlling the transistor type or enhancement type (also called normally off). The transistor 111 is also called a first transistor.

[0043] One of the gate and back gate of the transistor 112 is provided 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 ninja.

[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 a terminal Either the source or the 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. The output 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 turned on.

[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 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 the terminal OUTB 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 with reference to FIGS. I will explain this in more detail.

[0050] FIG. 2(A) shows a circuit diagram similar to FIG. 1(B), and FIG. 2(B) shows the operation of FIG. 2(A). 13 shows a timing chart for explaining the above.

[0051] In the timing chart shown in FIG. 2B, at times T1 to T2 and at 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 off. The transistor 112 is normally off, and the transistor 114 is normally off. The OUT terminal is at a low level based on the potential VSS. The OUTB terminal is at a low level based on the potential VDD. This results in a high level potential.

[0052] By adopting this configuration, the potential applied to the back gate of the transistor can be switched. For example, in the circuit symbol of the transistor 115 shown in FIG. The gate of the transistor is g, the back gate of the transistor is bg, and the source of the transistor is The source potential of the transistor is s and the drain potential of the transistor is d. The current (Id) flowing through the drain of a transistor and the gate voltage (Vg) when 0V is used As shown in the figure, the voltage at the back gate is the potential VSS (Vb g=0) to positively shift the threshold voltage and make it normally off. In addition, the voltage at the back gate is set to the potential VDD (Vbg=VDD) to master the threshold voltage. It is possible to inversely shift the input terminals 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 It is possible to reliably reduce the shoot-through current between the DDL and the wiring VSSL.

[0054] In the timing chart shown in FIG. 2B, between times T2 and T3, The input signal to be applied to terminal INB is set to a low level, and the inverted input signal to terminal INB is set to a high level. The transistor 111 is normally off, and the transistor 113 is normally off. The transistor 112 is normally on, and the transistor 114 is on. The terminal OUT is at the potential VDD. The OUTB terminal becomes 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 makes it possible to reliably reduce the shoot-through current between the VDDL and VSSL wiring. 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 is a two-wire inverter circuit. In Figure 2(C), the circuit symbol for a two-wire system is shown.

[0057] In FIG. 1B, the back gates of the transistors 111 and 112 are In FIG. 4, the configuration in which the terminals IN and INB are connected is illustrated. As shown in the circuit diagram of circuit 102A, the terminals IN and INB are connected to the gate side. This is also 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. By switching the connection between Fig. 1(B) and Fig. 4, the channel The electric field strength in the region where the transistor is formed can be adjusted. This allows the shift amount of the threshold voltage to be adjusted. The gate insulating film on the side where the terminals IN and INB are connected can be formed as follows: With this configuration, the input signal to the terminal IN and the terminal INB The switching characteristics of the input signal and the inverted input signal can be improved.

[0059] By using the above-described configuration, a semiconductor device having a logic circuit formed of OS transistors can be The device can achieve highly reliable operation while consuming less power. This can be done.

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

[0061] The logic circuit 102B shown in FIG. 5A functions as an inverter circuit, similar to that shown in FIG. 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 12 5A includes a wiring VDHL to which a high power supply potential VDH is applied, A wiring VDDL to which a potential VDD is applied, and a wiring VSS to which a low power supply potential VSS is applied L is illustrated. Note that the high power supply potential VDH is a potential higher than the high power supply potential VDD.

[0063] One of the gate and the 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 transistor 12 2. The gate or back gate of transistor 121 is connected to 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 the terminal OUTB is controlled to be at 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 of the back gates 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 or not 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 the drain of the transistor 124 is connected to a terminal OUT.

[0070] Transistor 124 is turned on or off depending on the potentials applied to its gate and back gate. is turned off, and it controls whether 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 a terminal Either the source or the 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. , 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 a terminal Either the source or the drain of the transistor 126 may be connected to IN. The source or drain of the transistor 126 is connected to a terminal OUT for outputting 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. The output 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 a terminal I NB. Either the gate or the back gate of the transistor 127 is connected to 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 transistor 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 potential of the gate and back gate of the transistor 122 is 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 a terminal I NB. Either the gate or the back gate of the transistor 128 is connected to 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 the terminal OUTB 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.

[0079] In FIG. 5A, the back gates of the transistors 121 and 123 are In FIG. 5B, the configuration in which the terminals IN and INB are connected is shown. 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 of.

[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 The gate insulation on the side where the terminals IN and INB are connected can be adjusted. The film is preferably thin. With this configuration, the terminals IN and INB are The switching characteristics of the input signal and the inverted input signal can be made excellent.

[0081] Next, the operation of the logic circuit 102B shown in FIG. 5A will be described with reference to FIGS. 6A and 6B. I will use this 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 backgate nodes of register 124 are illustrated as nodes PB.

[0083] In the timing chart shown in FIG. 6B, at times T5 to T6 and at time T7 In the periods T1 to T8, 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 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 P is at a high level based on the potential VDH. The node PB is at the potential VSS, and the transistor 122 is turned on. The potential of the terminal OUT becomes low level, and the transistor 124 is turned off. The OUTB terminal becomes 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 shoot-through current between the wiring VDHL and VSSL. 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 makes it possible to increase the voltage that can be applied and reduce the voltage drop equivalent to the threshold voltage, 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) for a power supply voltage of 1.2 V and Fig. 24(B) for a power supply voltage of 2.5 V. 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, at times T6 to T7, The input signal to be applied to terminal INB is set to a low level, and the inverted input signal to terminal INB is set to a 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, it is possible to reliably reduce the shoot-through current between the wiring VDHL and the wiring VSSL. 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 makes it possible to increase the voltage that can be applied, and reduce the voltage drop due to the threshold voltage, making it more reliable. In addition, 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. 6A 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 symbols can be represented as:

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

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

[0093] FIG. 7 is a circuit diagram of a logic circuit to which the configuration of FIG. 4 is applied. 7 includes transistors 131 to 138. 1 illustrates 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. The terminals OUT and OUTB are terminals that provide output signals. The terminal OUT outputs the input signal. The output signal according to the negative logical product (the negative logical sum of the inverted input signals) is obtained from the OUTB terminal. 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-parallel converters, processors, These circuits are made 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 the shoot-through current and suppress the voltage drop by the threshold voltage. etc. can be achieved.

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

[0097] FIG. 8A shows an example of an IC. The IC 7000A shown in FIG. The IC 7000A is implemented on, for example, a printed circuit board 7002. A number 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. In the circuit section 7003A, various circuits shown in the above embodiment are mounted on one die or multiple die. The circuit portion 7003A is divided into several dies. 1, wiring layer 7032.

[0098] The OS transistor layer may be a single layer or may be stacked with a wiring layer interposed therebetween. Specifically, FIG. 8B shows another example of an IC. The IC7000B shown in FIG. 8B is The IC 7000B has a lead 7001 and a circuit portion 7003B. 7002. Multiple such IC chips are combined, each of which is a printer. A substrate (mounting substrate 70) on which electronic components are mounted by being electrically connected on a substrate 7002 In the circuit portion 7003B, various circuits shown in the above embodiment modes are integrated in one step. The circuit section 7003A is an OS transceiver. The OS transistor layer 7031, the wiring layer 7032, and the OS transistor layer 7033. 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 further connected via another wiring layer. It is also possible to arrange multiple OS transistor layers. 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 IC7000A and 7000B are packaged as QFPs (Qua d Flat Package), but the form of the package is not limited to this. do not have.

[0100] The configurations, methods, etc. described in this embodiment may be different from the configurations, methods, etc. described in other embodiments. They can be used in appropriate combination.

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

[0102] FIG. 9A is a block diagram of a semiconductor device according to this embodiment. The semiconductor device 100A is 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 referred to as 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 is a sequential circuit using a CMOS circuit. It can be configured by appropriately designing using combinational circuits.

[0105] The signal processing circuit 201 is a circuit configured with OS transistors (shown 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. Signal processing 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] FIG. 9B is a circuit diagram showing an example 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 silicon transistors, the electrical characteristics of silicon transistors do not change much in high temperature environments. Therefore, it is possible to achieve highly reliable operation even in a high temperature environment.

[0108] FIG. 9C is a circuit diagram showing a specific circuit configuration of the logic circuit 202. The logic circuit 202 shown in FIG. 2C includes a switch and a logic circuit that functions as 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 A switch circuit 203 that is turned on or off in response to CLKb, and 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. Fig. 10(A) shows a two-wire inverter circuit, similar to Fig. 2(C). The logic circuit 102 is connected to a line 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 Fig. 2(C) and Fig. 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 also shown in FIG. 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 illustrated as node PB.

[0112] One of the gate and the 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 transistor 12 2. The gate or back gate of transistor 121 is connected to 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 the terminal OUTB is controlled to be at 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 of the back gates 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 or not 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 the drain of the transistor 124 is connected to a terminal OUT.

[0119] Transistor 124 is turned on or off depending on the potentials applied to its gate and back gate. is turned off, and it controls whether 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 a terminal Either the source or the 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. , 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 a terminal Either the source or the drain of the transistor 126 may be connected to IN. The source or drain of the transistor 126 is connected to a terminal OUT for outputting 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. The output 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 a terminal I NB. Either the gate or the back gate of the transistor 127 is connected to 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 transistor 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 potential of the gate and back gate of the transistor 122 is 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 a terminal I NB. Either the gate or the back gate of the transistor 128 is connected to 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 the terminal OUTB 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.

[0128] By adopting this configuration, as explained in FIG. 3(A) and (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 for explaining 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. 10C, the times T11 to T12 and At times T13 and T14, the input signal applied to the terminal IN is at a high level, and the input signal applied 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. The node P is at the potential VDH. The node PB is at a high 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 a low-level potential based on the potential VSS. This is the potential of the

[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 shoot-through current between the wiring VDHL and VSSL. 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 makes it possible to increase the voltage that can be applied, and reduce the voltage drop due to the threshold voltage, making it more reliable. In addition, the potential of the terminal OUTB can be set to the potential VDD.

[0133] In the timing chart shown in FIG. 10(D), between times T12 and 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 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 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, it is possible to reliably reduce the shoot-through current between the wiring VDHL and the wiring VSSL. 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 set to a value lower than the This makes it possible to increase the voltage applied to the device and reduce the voltage drop due to the threshold voltage, resulting in a more reliable operation. In fact, the potential of the terminal OUTB can be set to the potential VDD.

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

[0137] The switch circuit 203 shown in FIG. 11A is a switch circuit 20 shown in FIG. As shown in 3A, the wiring that provides 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 in addition to the wiring that supplies the clock signal CLK. The on / off control is performed according to the signal given to the gate and back gate. 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 state of a transistor. In addition, it is possible to control the threshold voltage of the transistor.

[0139] Alternatively, the switch shown in FIG. 11(D) may be used. The switch circuit 203C includes wiring for providing a clock signal CLK, and the gates and 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 adopting the above-described configuration, a semiconductor device having a logic circuit formed of OS transistors can be manufactured. The device is capable of achieving highly reliable operation while consuming less power. In addition, a configuration can be achieved in which the voltage drop of the output signal is suppressed.

[0141] Next, a configuration different from the above-described configuration 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 diagram illustrates a line VDDL and a wiring VSSL to which a low power supply potential VSS is applied. Terminals N1, IN1B, IN2 and 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 AND (NOR of the inverted input signal) is obtained from the terminal OUTB. An output signal is obtained according to the logical AND of the input signals (logical AND of the inverted input signals). 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 FIG. 12A is a two-wire NAND circuit. The circuit symbol for a two-wire NAND circuit is shown in Figure 12(B). The wiring name may be omitted.

[0144] By using the above combinational circuits, counters, serial-parallel converters, processors, These circuits are made 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 the shoot-through current and suppress the voltage drop by 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. 2 shows a circuit diagram of a power-gating enabled logic circuit 202A. The logic circuit 202A includes the logic circuit 102 and the switch circuit 203, as well as a reset signal RST A logic circuit 102E to which an inverted reset signal RSTb is input, The switch circuit 203D receives the signals PG and BG.

[0146] The switch circuit 203D is controlled to be turned on or off in response to a signal PG. This 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 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 02A.

[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. 1 illustrates the circuit symbol symbol.

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

[0149] In the timing chart shown in FIG. 14, signal processing At this time, the BG signal is set to low level. As a result, the transistor in the switch circuit 203D is put into a normally-off state. At time T22 to T23, the signal PG is set to a low level. A charge according to data is held in the capacitive element connected to the

[0150] Between times T23 and T24, the voltages VDD and VDH are set to a low level, and During this time, the current flowing through the nodes SN and SNb is The capacitive element holds a charge according to the data. Therefore, the node SN and the node S The capacitive 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 each other in a 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 generated at node SN and is output from the logic circuit 102 connected to node SNb to the logic circuit 102E.

[0153] At 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 just before the node SN and the node SNb are held 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 shoot-through current between the wiring VDHL and the wiring VSSL can be reliably reduced.

[0155] The configuration described 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 that transmits an inverted input signal and an inverted output signal Similarly, the logic circuit 20 shown in FIG. It can also be realized by replacing the NAND circuit with a NOR circuit, as in the circuit diagram for 2C. be.

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

[0157] The configurations, methods, etc. described in this embodiment may be different from the configurations, methods, etc. described in other embodiments. They can be used in appropriate combination.

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

[0159] <Example of transistor structure> 17A to 17C show an example of 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 of up to 200°C. Since it has good switching characteristics, it has excellent reliability 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 (B), the insulator 512, the insulator 514, and the insulator The insulating body 512, the insulating body 514, and the insulating body 516 are stacked in 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, the insulator 514 may be configured to receive the transistor 500 from, for example, an underlying substrate. It is preferable to use a film having a barrier property to prevent diffusion of hydrogen and impurities in the region where the .

[0163] As an example of a film that has a barrier property against hydrogen, silicon nitride formed by CVD method 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 are used. is preferred.

[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 does not allow impurities such as oxygen and moisture to pass through the membrane. Aluminum oxide is highly resistant to hydrogen, moisture, etc. 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 constitutes the 00. 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 having a relatively low dielectric constant. By using an insulating film between the wirings, the parasitic capacitance between the wirings can be reduced. As the insulating film 512 and the insulator 516, a silicon oxide film, a silicon oxynitride film, or the like may be used. This can be done.

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

[0167] As shown in FIGS. 17A and 17B, the transistor 500 is disposed on an insulator 516. The insulating material 520 is disposed on the insulating material 520, the insulating material 522 is disposed on the insulating material 520, and the insulating material 522 is disposed on the insulating material 520. An insulator 524 is disposed on the insulating layer 524, an oxide 530a is disposed on the insulating layer 524, 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 having an opening formed thereon and overlapping the conductor 542a and the conductor 542b. 580, a conductor 560 disposed in the opening, oxide 530b, conductor 542a, conductor The conductive body 542b and the insulator 550 disposed between the insulator 580 and the conductive body 560. , oxide 530b, conductor 542a, conductor 542b, and insulator 580, and insulator 550 and an oxide 530c disposed therebetween.

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

[0169] In the following, the oxide 530a, the oxide 530b, and the oxide 530c are collectively referred to as oxides 530a, 530b, and 530c. The conductor 542a and the conductor 542b are collectively referred to as oxide 530. In some cases, the conductor 542 is also referred to as the 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 laminated. However, the present invention is not limited thereto. For example, a single layer of oxide 530b, A two-layer structure of oxide 530b and oxide 530a, and a 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 having a two-layer laminate structure, the present invention is not limited thereto. For example, the conductor 560 may have a single-layer structure or a laminated structure of three or more layers. The transistor 500 illustrated 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 a 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 between them. The arrangement of the conductor 542b is selected to be self-aligned with respect to 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-aligning manner without providing a margin for alignment. Since the transistor 500 can be formed without any problem, the area occupied by the transistor 500 can be reduced. This allows miniaturization and high integration of semiconductor devices.

[0172] Furthermore, a conductor 560 is formed in a self-aligned manner in the region between the conductors 542a and 542b. Since the conductor 560 is formed, the conductor 560 overlaps with the conductor 542a or the conductor 542b. 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. It is possible to improve the scanning speed and provide 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 insulator in which a part of oxygen is released by heating is used. It is preferable to use oxide materials that release oxygen when heated. Thermal Desorption Spectroscopy (DSA) analysis revealed that oxygen atoms The converted amount of oxygen released is 1.0 x 10 18 atoms / cm 3 More than or equal to 1.0 ×10 19 atoms / cm 3 More preferably, 2.0×10 19 atoms / c m 3 or more than 3.0×10 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 range of 00°C or more and 400°C or less is preferable.

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

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

[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 material 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 for the 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 Insulators containing oxides of aluminum and / or hafnium are recommended. The oxides include aluminum oxide, hafnium oxide, aluminum and hafnium. It is preferable to use oxide (hafnium aluminate) etc. When the insulator 522 is formed by the above method, the insulator 522 is resistant to oxygen release from the oxide 530 and to A layer for suppressing the intrusion of impurities such as hydrogen from the periphery of the transistor 500 into the oxide 530 is provided. It works like this.

[0180] Alternatively, for example, aluminum oxide, bismuth oxide, germanium oxide, etc. may be added to these insulators. 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] In addition, 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 laminated structure that is thermally stable and has 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, and may be made of different materials. A laminated structure may also be used.

[0183] In the transistor 500, an oxide semiconductor is added to an oxide 530 including a channel formation region. It is preferable to use a metal oxide that functions as the oxide 530. For example, In-M- Zn oxide (element M is aluminum, gallium, yttrium, copper, vanadium, beryllium, Sodium, boron, titanium, iron, nickel, germanium, zirconium, molybdenum, lambda tantalum, cerium, neodymium, hafnium, tantalum, tungsten, or magnesium It is preferable to use a metal oxide such as one or more selected from the group consisting of fluorine, ... As the material 530, In-Ga oxide or In-Zn oxide may be used.

[0184] The metal oxide serving as the channel forming region in the oxide 530 is a band gap metal oxide. It is preferable to use an electron pump having a peak of 2 eV or more, preferably 2.5 eV or more. By using metal oxides with a wide band gap, the off-state current of transistors can be reduced. It is possible.

[0185] The oxide 530 has an oxide 530a under the oxide 530b. The diffusion of impurities from the structure 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 The atomic ratio of element M in the oxide 530b is the atomic ratio of element M in the metal oxide in the constituent elements. It is preferable that the atomic ratio of the metal oxide 530a is larger than that of the element M. In the metal oxide used for the oxide 530b, the atomic ratio of element M to In is It is preferable that the atomic ratio of element M to In is larger than that of element In. In the metal oxide used, the atomic ratio of In to the element M is It is preferable that the atomic ratio of In is larger than that of the element M in the metal oxide. The oxide 530c is a metal oxide that can be used for the oxide 530a or the oxide 530b. The object can be used.

[0187] In addition, the energy of the conduction band minimum of the oxide 530a and the oxide 530c is It is preferable that the energy of the oxide is higher than the minimum energy of the conduction band of 0b. 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 530c and the oxide 530b is In order to achieve this, the oxide 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 a low defect level density is formed. For example, when the oxide 530b is an In-Ga-Zn oxide, the oxide 530a and oxide 530c are In-Ga-Zn oxide, Ga-Zn oxide, oxide For example, gallium nitride may be used.

[0190] At this time, the main path of the carriers is the oxide 530b. By configuring the oxide 530c as described above, the interface between the oxide 530a and the oxide 530b and the oxide This can reduce the defect state density at the interface between the nitride 530b and the oxide 530c. Therefore, the effect of interface scattering on carrier conduction is reduced, and the transistor 500 has high A high 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. The conductor 542 is made of aluminum. Aluminum, Chromium, Copper, Silver, Gold, Platinum, Tantalum, Nickel, Titanium, Molybdenum, Tan 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. For example, tantalum nitride, titanium nitride, tungsten nitride, etc. titanium and aluminum nitrides, tantalum and aluminum nitrides, ruthenium 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 their conductivity even when they absorb oxygen. Therefore, it is preferable.

[0192] As shown in FIG. 17A, the interface between the oxide 530 and the conductor 542 and its vicinity In the semiconductor device, 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 a region between 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 the region 543 may be reduced. In such a case, a metal compound layer containing a component of 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 suppresses 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: hafnium, aluminum, gallium, yttrium, zirconium tungsten, titanium, tantalum, nickel, germanium, or magnesium For example, 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. Aluminum oxide, hafnium oxide, aluminum and hafnium oxide, which are insulators containing It is preferable to use oxides containing hafnium (e.g., hafnium aluminate). Hafnium aluminate has higher heat resistance than hafnium oxide. In the heat treatment, the conductor 542 is preferably made of a material having oxidation resistance. When using materials that absorb oxygen and whose conductivity does not decrease significantly, 544 is not an essential component and may be appropriately designed depending on the desired transistor characteristics.

[0197] The insulator 550 functions as a gate insulating film. It is preferable to place the insulator 550 in contact with the upper and side surfaces of the insulator 550. 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 More than 1.0×10 19 atoms / cm 3 More preferably 2.0 ×10 19 atoms / cm 3 or more than 3.0×10 20 atoms / cm 3 That's it The surface temperature of the film during the TDS analysis was 100°C or less. The range of up to 700°C is preferable.

[0198] Specifically, silicon oxide having excess oxygen, silicon oxynitride, silicon nitride oxide, Silicon nitride, silicon oxide doped with fluorine, silicon oxide doped with carbon, 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] The insulator 550 is an insulator that releases oxygen when heated, and is placed on the top surface of the oxide 530c. By providing the oxide 530b in contact with the insulator 550, the oxide 530b passes through the oxide 530c. 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 be 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 insulator 550 and the conductor 560. The metal oxide serves as an insulating material. 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, the reduction in the amount of excess oxygen supplied to the oxide 530 can be suppressed. In addition, the 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 (e.g., oxygen atoms, oxygen molecules, etc.). It is preferable to use a conductive material having a function of suppressing the diffusion of at least one of the conductive materials. Since 60a has a 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 ruthenium. It is preferable to use ruthenium, ruthenium oxide, or the like.

[0203] The conductor 560b is a conductive material mainly composed of tungsten, copper, or aluminum. In addition, since the conductor 560b also functions as wiring, It is preferable to use a conductor with high electrical conductivity, such as tungsten, copper, or aluminum. The conductive material 560b may be a conductive material mainly composed of aluminum. 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, silicon oxide doped with fluorine , silicon oxide doped with carbon, silicon oxide doped with carbon and nitrogen, silicon oxide with vacancies It is preferable that the insulating layer 100 has silicon oxide or resin. In particular, silicon oxide and oxide Silicon nitride is preferred because it is thermally stable. In particular, silicon oxide and oxide having vacancies are preferred. Silicon oxide is preferred because it allows for easy formation of excess oxygen regions in a later 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 of the insulator 580 is formed to overlap the region between the conductor 542a and the conductor 542b. As a result, the conductor 560 is in contact with the opening of the insulator 580 and the conductor 542a. It is formed so as to be embedded in the region sandwiched between bodies 542b.

[0207] In miniaturizing semiconductor devices, it is necessary 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 high aspect ratio. The conductor 560 is provided so as to be embedded in the opening of the insulator 580. Even if the shape has a high ratio, the conductor 560 can be formed without collapsing 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. It is preferable that the insulator 574 is 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 provided 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 ruthenium, cadmium, and ruthenium. Cut.

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

[0211] In addition, it is preferable to provide an insulator 581 functioning 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 disposed in the opening. The conductor 540a and the conductor 540b are disposed opposite each other with the conductor 560 in between. The symbol b functions 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 the fluctuation of electrical characteristics and improve reliability. It is possible to provide a transistor including an oxide semiconductor having a large on-state current. It is possible to provide a transistor including an oxide semiconductor and having a low current. It is possible to provide a semiconductor device having an oxide semiconductor. 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> A structural example of a 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 a portion indicated by a dashed line L1-L2 in FIG. 18A is a cross-sectional view of a portion indicated by a chain line W1-W2. For clarity, some elements are omitted in the illustration.

[0216] In FIG. 18(A), (B), and (C), a transistor 510A and a thin film that functions as an interlayer are shown. Insulators 511, 512, 514, 516, 580, and 582, and insulator 584. Also shown is a transistor 510A electrically connected to The conductors 546 (conductors 546a and conductors 546b) function 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 (oxide 530a, oxide 530b, and oxide 530c) that are 30c), a conductor 542a serving as one of the source or drain, and a has a conductor 542b which functions as the other drain, and an insulator 574.

[0218] In addition, in the transistor 510A shown in FIGS. 18(A), (B), and (C), the oxide 5 30c, an insulator 550, and a conductor 560 are inserted into an opening in an 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 conductor 542a and 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. , hafnium oxide, tantalum oxide, zirconium oxide, lead zirconate titanate (PZ T), strontium titanate (SrTiO3) or (Ba,Sr)TiO3 (BST ) can be used in a single layer or a multilayer. 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 insulator from mixing with 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 unlikely to penetrate the insulating material). It has a function of suppressing the diffusion of oxygen (e.g., 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 to the transistor 510A side through the insulator 511. It is possible to suppress the above.

[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 the transistor 510A, the 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 between the substrate and the impurities such as water or hydrogen. It is preferable that the fluorine-containing compound functions as a barrier film to prevent the fluorine-containing compound from being mixed into the transistor 510A. With this structure, impurities such as hydrogen and water can enter the transistor from the substrate side rather than the insulator 514. The insulator 516 can suppress the diffusion of the insulating material to the 510A side. It is preferable that the dielectric constant of the interlayer is lower than that of the substrate 514. By using a material with a low dielectric constant as the interlayer, The parasitic capacitance occurring between wirings can be reduced.

[0225] In addition, the insulator 522 preferably has a barrier property. By having such a structure, it is possible to prevent impurities such as hydrogen from being introduced into the transistor 510A from the periphery of the transistor 510A. 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, or the like. 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 used as single layers or As transistors become smaller and more highly integrated, Thinning of the gate insulating film may cause problems such as leakage current. By using a high-k material as an insulator that functions as a gate insulator, the transistor can be This makes it possible to reduce the gate potential during start operation.

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

[0228] The oxide 530 having a region that functions as a channel formation region is made up of an oxide 530a and an oxide 5, an oxide 530b is formed on the oxide 530a, and an oxide 530c is formed on the oxide 530b. By having the oxide 530a under the oxide 530b, the oxide 530a is formed below the oxide 530a. The diffusion of impurities from the structure 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 insulating layer, 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 insulator 580 is preferably provided. 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 a barrier property against hydrogen and oxygen, and is also 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. Also, an aluminum film may be laminated on a tungsten film. A two-layer structure in which a copper film is 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] In addition, a titanium film or titanium nitride film and an alumina film are laminated on the titanium film or titanium nitride film. An aluminum film or a copper film is laminated, and then a titanium film or a titanium nitride film is formed on the aluminum film or a copper film. 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 film or Indium oxide, tin oxide or molybdenum nitride are also used. 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. In particular, aluminum oxide, Using insulating films with barrier properties against oxygen and hydrogen, such as hafnium oxide and gallium oxide. It is also preferable to use silicon nitride formed by a CVD method.

[0236] The inclusion of 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. There can be.

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

[0238] As transistors become smaller and more highly integrated, the gate insulating film becomes thinner, causing the leakage current to increase. In this case, the insulator 550 may have a laminated structure. The insulator that functions as the gate insulating film is made of a high-k material and a thermally stable material. By forming a laminated structure with a material, the gate potential during transistor operation can be controlled while maintaining the physical thickness. In addition, it is possible to obtain a laminated structure that is thermally stable and has a high relative dielectric constant. .

[0239] The conductor 560 functioning as a gate electrode is a conductor 560a and a conductor 560b on the conductor 560a. 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 a function of suppressing the diffusion of impurities. Has a function of suppressing the diffusion of oxygen (e.g., 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, so that 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 0a, 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 conductor electrode.

[0242] The conductor 560b is 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 having a low resistance. For example, tungsten, copper, or aluminum may be used as the main material. The conductor 560b may have a laminated structure. For example, a laminate of titanium, titanium nitride and the above-mentioned 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, it is preferable to use aluminum oxide or hafnium oxide. 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 oxide nitride or silicon nitride can be used.

[0244] By providing the insulator 574, impurities such as water and hydrogen contained in the insulator 580 can be converted into oxygen. 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 suppress the oxidation of the conductor 560. It is possible.

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

[0246] The insulator 582, like the insulator 514, prevents impurities such as water or hydrogen from entering the It is preferable that the insulating film functions as a barrier insulating film that prevents the metal oxide 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 caused by the

[0248] Transistor 510A is also connected to insulators 580, 582, and 584. Electrical connection to other structures may be made through plugs or wiring such as the embedded conductor 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 form. 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 a barrier property against hydrogen and oxygen. By using a layered structure of conductive tantalum nitride and highly conductive tungsten, It is possible to suppress the diffusion of impurities from the outside while maintaining the electrical conductivity of the wiring. .

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

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

[0253] Transistor 510B is a modification of transistor 510A. To avoid confusion, the following description will focus mainly on the differences from transistor 510A.

[0254] Transistor 510B includes conductor 542 (conductor 542a and conductor 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 transistor with high performance can be provided.

[0255] The conductor 560 functioning as a gate electrode is a conductor 560a and a conductor 560b on the conductor 560a. 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 a function of suppressing the diffusion of impurities. Has a function of suppressing the diffusion of oxygen (e.g., 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, so that 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 surface 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. In addition, for example, magnesium oxide, gallium oxide, germanium oxide, and yttrium oxide are also available. metals such as lithium oxide, 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 prevented from being absorbed by the transistor. Therefore, diffusion to register 510B can be suppressed.

[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 plugs and wiring can be For example, the conductor 546 can be made of a material that absorbs oxygen. By using metal materials with high electrical conductivity, a semiconductor device with low power consumption can be provided. Specifically, tungsten and aluminum have low oxidation resistance, while In addition, for example, a material that is easy to form a film or process can be used. An electrical conductor may be used.

[0261] <Transistor structure example 3> A structural example of a 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 a portion indicated by a dashed line L1-L2 in FIG. 20(A) is a cross-sectional view of a portion indicated by a chain line W1-W2. For clarity, some elements are omitted in the illustration.

[0262] Transistor 510C is a modification of transistor 510A. To avoid confusion, the following description will focus mainly on the differences from transistor 510A.

[0263] The transistor 510C shown in FIGS. 20A, 20B, and 20C includes 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 530b. 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. This allows the effective channel of the transistor 510C to be 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). It is preferable that the conductor 546a (conductive In the etching for forming the opening for embedding the conductor 547a (conductor 546b), 47b) acts as a stopper to prevent oxide 530b from being over-etched. It is possible.

[0266] In addition, the transistor 510C shown in FIGS. Alternatively, an insulator 545 may be disposed on top of the substrate 4. 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 intrusion of In addition, an insulator 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> A structural example of a 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 a portion indicated by a dashed line L1-L2 in FIG. 21(A) is a cross-sectional view of a portion indicated by a chain line W1-W2. For clarity, some elements are omitted in the illustration.

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

[0269] In FIG. 21(A) to (C), an insulator 550 is provided on the oxide 530c. 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. Also, 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 conductor 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, the oxidation of the conductor 560 due to 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 to form a metal oxide 5 The electrical resistance of 52 can be reduced to make it a conductive layer. The electrode can be called an inductor.

[0272] The metal oxide 552 may 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. However, the metal oxide 552 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 a part of the film may be laminated thereon.

[0274] When the metal oxide 552 functions as a gate electrode, It is possible to improve the on-state current of transistor 510D without weakening the effect of the electric field from these. Alternatively, when it functions as a gate insulating film, the insulator 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 laminated 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 from the conductor 560 to the oxide 530 are , and can be easily adjusted appropriately.

[0275] Specifically, the resistance of an oxide semiconductor that can be used for the oxide 530 is reduced. Metal oxide 552 can be used. Alternatively, hafnium, aluminum, gallium, tungsten, titanium, tantalum, nickel, gel A metal containing one or more of the following metals: 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 oxide, ha ... It is preferable to use hafnium aluminate. In particular, hafnium aluminate is It has higher heat resistance than hafnium oxide film. Therefore, it is possible to prevent the formation of oxide film during heat treatment in the subsequent process. It is preferable because it is difficult to crystallize. Note that the metal oxide 552 is not an essential component. Appropriate design may be made 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 may be used. In this way, the conductor 560 is prevented 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. The above-mentioned problems can be suppressed.

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

[0279] In addition, 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 layer may also function as a barrier layer. In this case, the insulator 570 does not need to be provided.

[0280] Using the insulator 571 as a hard mask, the insulator 570, the conductor 560, and the metal oxide 552, insulator 550, and oxide 530c are selectively removed to remove these The sides of the oxide 530b can be made substantially flush with each other and a portion 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. Either region 531a or region 531b serves as a source region. one serves as a drain region, and the other serves as a drain region.

[0282] The regions 531a and 531b may 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 doping the surface of the oxide 530b with an impurity element such as phosphorus or boron. In the present 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, forming the regions 531a and Region 531b may 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 And 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 formation region and the source / drain region (region 531a 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 makes it possible to reduce the minimum voltage and improve the operating frequency.

[0286] In order to further reduce the off-state current, an off-type MOSFET is placed between the channel formation region and the source / drain region. An offset region may be provided. The offset region is a region having a high electrical resistivity. The offset region is a region where the dopant element is not introduced. This can be achieved by introducing the above-mentioned impurity element 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, and an insulator 570. The insulator 575 is disposed on the side of the edge 550 and the oxide 530c. It is preferable to use an insulator with a low dielectric constant. For example, silicon oxide, silicon oxynitride, Silicon oxynitride, silicon nitride, silicon oxide with fluorine, silicon oxide with carbon Silicon, silicon oxide doped with carbon and nitrogen, silicon oxide with vacancies, or Resins are preferable. In particular, silicon oxide, silicon oxynitride, and silicon nitride oxide are preferable. In the case of using silicon oxide with voids as the insulator 575, the insulator 575 can be used in a later process. 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 formula:

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

[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 oxide 230 and insulator 575.

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

[0291] Transistor 510E is a variation of the transistor described above. In order to prevent this, differences from the above transistor will be mainly described.

[0292] In FIG. 22A to FIG. 22C, the conductor 542 is not provided, and the exposed oxide 530 b has regions 531a and 531b on a portion of the surface. One of the 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 region 531 (region 531a and region 531) shown in FIG. 22(A) to FIG. 22(C) b) is a region in which 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 to It is preferable to 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. can be used. 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 a method such as y Ion Mass Spectrometry.

[0296] In particular, boron and phosphorus are used in the manufacturing process 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 thin film are formed on the oxide 530b and the dummy gate. 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 formed. An overlapping area with the edge 550 can be provided.

[0298] Specifically, after forming an insulating film that will become the insulator 580 on the insulating film that will become the insulator 574, The insulating film that will become the insulating film 580 is CMP (Chemical Mechanical Polishing). By performing a dummy gate insulating film (580) etching process, a part of the insulating film that will become the insulator 580 is removed. When the dummy gate is subsequently 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 the insulating material. The opening has a bottom surface on which the insulating material 574 and the insulating material 573 are exposed. 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 that becomes the insulator 550 and a conductive film that becomes the conductor 560 in this order, The oxide film that becomes the oxide 530c and the insulator 55 are removed by CMP processing or the like until the oxide 580 is exposed. 22(A) and the insulating film which will become conductor 560 are removed. 22C can be formed.

[0299] Note that the insulator 573 and the insulator 574 are not essential components. Appropriate design may be required depending on the characteristics.

[0300] The transistors shown in FIGS. 22A to 22C can be made using 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] (Embodiment 4) 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. Examples of electronic devices include ICs for control processors in In addition to vehicles and other moving objects, vacuum cleaners, microwave ovens, electric ovens, rice cookers, water heaters, induction cookers Cooking appliances, water servers, heating and cooling appliances including air conditioners, washing machines, dryers , audio-visual 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 above controls devices such as sensors and actuators in the automobile 5700. The present invention can be used in a control system for

[0306] FIG. 23B is a diagram showing an electric two-wheeled vehicle 5800 as an example of a moving object. The semiconductor device described above is used for equipment such as sensors and actuators 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, automobiles and electric motorcycles are described as examples of moving objects. The moving object is not limited to an automobile or an electric two-wheeled vehicle. For example, the moving object may be a train or a monorail. , ships, and flying objects (helicopters, unmanned aerial vehicles (drones), airplanes, rockets) The semiconductor device according to one embodiment of the present invention can be applied to these moving objects. Cut.

[0308] FIG. 23C 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 a 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 as an example of the electronic device. The semiconductor device described in the embodiment is a power supply for supplying current to 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] (Additional notes regarding the present specification, etc.) The above embodiment and each configuration in the embodiment 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, a plurality of configuration examples may be shown. In this case, the configuration examples can be appropriately combined.

[0314] In addition, the contents (or even a part of the contents) described in one embodiment may be used in the embodiment. Another content (or a 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. It is possible to do things like drawing.

[0315] The contents described in the embodiments are explained in detail with reference to various figures in each embodiment. The content is described in the specification or using sentences in the description.

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

[0317] In the present specification and the like, in the block diagrams, components are classified by function and are independent of each other. However, in actual circuits, the components are divided into functional blocks. In some cases, it is difficult to separate the functions into individual circuits, and multiple functions are involved in one circuit, or multiple circuits are involved in a single circuit. Therefore, the blocks in the block diagram may be expressed as The present invention is not limited to the described components, and may be rephrased appropriately depending on the situation.

[0318] In addition, in the drawings, the size, layer thickness, and area are shown arbitrarily for convenience of explanation. The drawings are not necessarily limited to the scale shown. The figures are merely schematic illustrations for the purpose of illustration, and are not limited to the shapes or values ​​shown in the drawings. , noise, signal, voltage, or current variations, or timing errors 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) and drain are as follows: source (drain) terminal, 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 intended to be limiting. For example, an "electrode" may be used as a part of a "wire." , and vice versa. Furthermore, the terms "electrode" and "wiring" may be used interchangeably to refer to the plural "electrodes" and "wirings." 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. This is 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 say that the voltage is equivalent to the potential. The ground potential is not necessarily 0V. It is important to note that 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 the term "conductive layer" In some cases, it may be possible to change the term to "conductive film." Or, for example, to "insulating film." In some cases, the term "insulating layer" may be changed to the term "insulating layer."

[0323] In this specification, a switch refers to a device that can be in a conductive state (on state) or a non-conductive state (off state). It refers to a device that has the function of controlling whether or not a current flows by switching to a non-operating state. A switch has a 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 refers to, for example, the width of a semiconductor (or a transistor) when it is in an on-state. The region where the gate electrode overlaps with the gate electrode (the part of the semiconductor through which current flows when the semiconductor is in the insulated state), or the channel This refers to the length of the portion where the source and drain face each other in the region where the MOSFET 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" means that there is an object between A and B that has some electrical effect. When a device is connected to a power source, it enables the transmission and reception of electrical signals between A and B. [Explanation of symbols]

[0327] IN1: terminal, IN2B: terminal, L1-L2: one-dot chain 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 102C: logic circuit; 102D: logic circuit; 102E: logic circuit; 111: transistor 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 switch circuit, 203D: switch circuit, 230: oxide, 300: transistor, 500 : transistor, 510A: transistor, 510B: transistor, 510C: 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 Edges, 581: Insulators, 582: Insulators, 584: Insulators, 5700: Automobiles, 5800 : Electric two-wheeler, 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

1. a first transistor to a fifteenth transistor, a first wiring and a second wiring, a first input terminal to a fourth input terminal, and a first output terminal and a second output terminal; one of a source and a drain of the first transistor is electrically connected to the first output terminal; the other of the source and the drain of the first transistor is electrically connected to the first wiring; one of a source and a drain of the second transistor is electrically connected to the other of a source and a drain of the third transistor; the other of the source and the drain of the second transistor is electrically connected to the first output terminal; a gate of the second transistor electrically connected to the first input terminal; one of a source and a drain of the third transistor is electrically connected to the second wiring; a gate of the third transistor electrically connected to the second input terminal; one of a source and a drain of the fourth transistor is electrically connected to a gate of the first transistor; the other of the source and the drain of the fourth transistor is electrically connected to the first wiring; a gate of the fourth transistor is electrically connected to a gate of the first transistor; a second gate of the fourth transistor electrically connected to the third input terminal; one of a source and a drain of the fifth transistor is electrically connected to a gate of the first transistor; the other of the source and the drain of the fifth transistor is electrically connected to the first wiring; a gate of the fifth transistor is electrically connected to a gate of the first transistor; a second gate of the fifth transistor electrically connected to the fourth input terminal; one of the source and the drain of the sixth transistor is electrically connected to the other of the source and the drain of the seventh transistor; the other of the source and the drain of the sixth transistor is electrically connected to the gate of the first transistor; a gate of the sixth transistor electrically connected to the first input terminal; one of a source and a drain of the seventh transistor is electrically connected to the second wiring; a gate of the seventh transistor electrically connected to the second input terminal; one of a source and a drain of the eighth transistor is electrically connected to a gate of the eighth transistor; the other of the source and the drain of the eighth transistor is electrically connected to the first wiring; a second gate of the eighth transistor electrically connected to the second input terminal; one of a source and a drain of the ninth transistor is electrically connected to the second wiring; the other of the source and the drain of the ninth transistor is electrically connected to the gate of the eighth transistor; a gate of the ninth transistor electrically connected to the fourth input terminal; one of the source and the drain of the tenth transistor is electrically connected to the gate of the tenth transistor; the other of the source and the drain of the tenth transistor is electrically connected to the first wiring; a second gate of the tenth transistor electrically connected to the first input terminal; one of a source and a drain of the eleventh transistor is electrically connected to the second wiring; the other of the source and the drain of the eleventh transistor is electrically connected to the gate of the tenth transistor; a gate of the eleventh transistor is electrically connected to the third input terminal; one of the source and the drain of the twelfth transistor is electrically connected to the other of the source and the drain of the thirteenth transistor; the other of the source and the drain of the twelfth transistor is electrically connected to the first wiring; a gate of the twelfth transistor is electrically connected to a gate of the tenth transistor; one of a source and a drain of the thirteenth transistor is electrically connected to the second output terminal; a gate of the thirteenth transistor is electrically connected to a gate of the eighth transistor; one of a source and a drain of the fourteenth transistor is electrically connected to the second wiring; the other of the source and the drain of the fourteenth transistor is electrically connected to the second output terminal; a gate of the fourteenth transistor electrically connected to the fourth input terminal; one of a source and a drain of the fifteenth transistor is electrically connected to the second wiring; the other of the source and the drain of the fifteenth transistor is electrically connected to the second output terminal; a gate of the fifteenth transistor is electrically connected to the third input terminal; Semiconductor device.

2. In claim 1, a first potential applied to the first wiring is higher than a second potential applied to the second wiring; Semiconductor device.

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