Semiconductor device

Abstract

To provide a semiconductor device having a new configuration.SOLUTION: A semiconductor device has: a first transistor in which one of a source or a drain is electrically connected to first wiring for reading data; a second transistor in which one of a source or a drain is electrically connected to a gate of the first transistor, the other of the source or the drain is electrically connected to second wiring for writing the data; and a third transistor in which one of a source or a drain is electrically connected to the gate of the first transistor, the other of the source or the drain is electrically connected to a capacitor for holding a charge according to the data, wherein the third transistor has a metal oxide in a channel formation region.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] This specification describes a semiconductor device and its operation method and the like.

[0002] In this specification, a semiconductor device is a device that utilizes semiconductor characteristics, and includes a circuit containing semiconductor elements ( transistors, diodes, photodiodes, etc.), a device having the same circuit, and the like. It also refers to all devices that can function by utilizing semiconductor characteristics. For example, integrated circuits , chips equipped with integrated circuits, and electronic components in which chips are housed in packages are examples of semiconductor devices. In addition, storage devices, display devices, light-emitting devices, lighting devices, and electronic devices, etc., are themselves semiconductor devices and may have semiconductor devices.

Background Art

[0003] Metal oxides have attracted attention as semiconductors applicable to transistors. Indium-gallium-zinc oxide, called "IGZO", "Igzo", etc., is a typical example of a multi-component metal oxide. In research on IGZO, a CAAC (c-axis aligned crystalline) structure and an nc (nanocrystalline) structure that are neither single crystals nor amorphous have been found (for example, Non-Patent Document 1). axis aligned crystalline) structure, and nc (nanocr ystalline) structure have been found (for example, Non-Patent Document 1).

[0004] A transistor having a metal oxide semiconductor in a channel formation region (hereinafter sometimes referred to as an "oxide semiconductor transistor", or "OS transistor".) has been reported to have an extremely small off-current (for example, Non-Patent Documents 1 and 2). Various semiconductor devices using OS transistors have been fabricated (for example, Non-Patent Documents 3 and 4). (for example, Non-Patent Documents 1 and 2). OS transistors have been used to fabricate various semiconductor devices (for example, Non-Patent Documents 3 and 4). The manufacturing process can be incorporated into a CMOS process with conventional Si transistors, The OS transistor can be stacked on the Si transistor (for example, Non-Patent Document 4).

Prior Art Documents

Non-Patent Documents

[0005]

Non-Patent Document 1

Non-Patent Document 2

Non-Patent Document 3

Non-Patent Document 4

Summary of the Invention

[0006] An object of one embodiment of the present invention is to provide a semiconductor device that functions as a memory device utilizing extremely small off-state current. To provide a semiconductor device having excellent reliability, such as long-term data retention, The object of the present invention is to provide a semiconductor device which is excellent in reducing power consumption.

[0007] The description of a plurality of problems does not preclude the existence of each problem. It is not necessary to solve all of the problems shown. Also, problems other than those listed may be solved by the present invention. This will become apparent from the above, and such a problem can also be one aspect of the present invention. [Means for solving the problem]

[0008] In one aspect of the present invention, one of the source and the drain is connected to a first wiring for reading data. A first transistor electrically connected to the first transistor, the source or the drain of which is The other of the source and drain is electrically connected to the gate of the transistor. a second transistor electrically connected to a second wiring for providing a second transistor having a source or a drain The other of the source and drain of the first transistor is electrically connected to the gate of the first transistor. a third transistor electrically connected to the capacitor for holding a charge according to the data; and the third transistor has a metal oxide in a channel formation region. It is a device.

[0009] In one embodiment of the present invention, the second transistor has a metal oxide in a channel formation region. The semiconductor device preferably has the following features.

[0010] In one aspect of the present invention, the first transistor preferably has silicon in a channel formation region. A semiconductor device having this is preferred.

[0011] In one aspect of the present invention, a semiconductor device in which the first wiring is the same wiring as the second wiring is preferred. is preferred.

[0012] One aspect of the present invention is an electronic device including the semiconductor device described above and a housing.

[0013] One aspect of the present invention is a method of operating the semiconductor device described above, the method including a data writing operation of bringing the second transistor and the third transistor into a conductive state, a data holding operation of bringing the third transistor into a non-conductive state, and a data reading operation of bringing the second transistor into a non-conductive state and bringing the third transistor into a conductive state. and the third transistor into a conductive state, a data holding operation of bringing the third transistor into a non-conductive state, and a data reading operation of bringing the second transistor into a non-conductive state and bringing the third transistor into a conductive state. A data holding operation of bringing the third transistor into a non-conductive state, and a data reading operation of bringing the second transistor into a non-conductive state and bringing the third transistor into a conductive state. A data reading operation of bringing the second transistor into a non-conductive state and bringing the third transistor into a conductive state. is a method of operating a semiconductor device.

[0014] For other aspects of the present invention, descriptions in the embodiments described below and in the drawings are provided. are described in the drawings.

Advantages of the Invention

[0015] According to one embodiment of the present invention, a semiconductor device that functions as a storage device using an extremely small off-current can provide a semiconductor device with excellent reliability such as long-term data retention, or can provide a semiconductor device with excellent low power consumption. In a semiconductor device that functions as a storage device using an extremely small off-current, a semiconductor device with excellent reliability such as long-term data retention can be provided, or a semiconductor device with excellent low power consumption can be provided. is capable of providing a semiconductor device with excellent low power consumption.

[0016] The description of a plurality of effects does not prevent the existence of other effects. Also, one embodiment of the present invention does not necessarily have to have all of the exemplified effects. Also, regarding one embodiment of the present invention, Regarding problems, effects, and novel features other than those described above, they can be understood from the description and drawings of this specification. It will become clear soon.

Brief Description of the Drawings

[0017]

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DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, embodiments of the present invention will be described. However, one embodiment of the present invention is not limited to the following description, and it will be easily understood by those skilled in the art that the form and details can be variously changed without departing from the spirit and scope of the present invention. Therefore, one embodiment of the present invention is not construed as being limited to the description of the embodiments shown below. In the present specification and the like, ordinal numbers such as "first", "second", and "third" are attached to avoid confusion of components. Therefore, they do not limit the number of components. Also, they do not limit the order of components. For example, in one of the embodiments of the present specification and the like, a component referred to as "first" may be a component referred to as "second" in other embodiments or in the claims. Also, for example, a component referred to as "first" in one of the embodiments of the present specification and the like may be omitted in other embodiments or in the claims.

[0019]

[0020] In the drawings, the same elements, elements having similar functions, elements of the same material, or elements formed simultaneously may be denoted by the same reference numerals, and repeated descriptions thereof may be omitted.

[0021] In this specification, for example, the power supply potential VDD may be described by omitting it as the potential VDD, VDD, etc. This also applies to other components (for example, signals, voltages, circuits, elements, electrodes, wirings, etc.).

[0022] Also, when the same reference numeral is used for a plurality of elements, particularly when it is necessary to distinguish them, identification symbols such as “_1”, “_2”, “[n]”, “[m,n]”, etc. may be appended to the reference numeral for description. For example, the second wiring GL may be described as wiring GL[2].

[0023] (Embodiment 1) A configuration example of a semiconductor device which is one aspect of the present invention and a method of operating the semiconductor device will be described with reference to FIGS. 1 to 14.

[0024] FIG. 1A shows an example of a circuit diagram of a semiconductor device. The semiconductor device 10 shown in FIG. 1A includes a transistor 11, a transistor 12, a transistor 13, and a capacitor 14.

[0025] The gate of the transistor 11 is connected to the wiring WWL. One of the source or drain of the transistor 11 is connected to the gate of the transistor 13 and one of the source or drain of the transistor 12. The other of the source or drain of the transistor 11 is connected to the wiring BL. In the description in FIG. 1A and this specification, the source of the transistor 11 ​​​​​One of the source or drain, the gate of transistor 13, and the source of transistor 12 The node to which one of the source or drain is connected is referred to as node MN1.

[0026] The gate of transistor 12 is connected to wiring RWL. The source or the other of the drain of transistor 12 is connected to one electrode of capacitor 14. The other electrode of capacitor 14 is connected to wiring CL. In the description in FIG. 1A and this specification, the other of the source or drain of transistor 12 and the node to which one electrode of capacitor 14 is connected are referred to as node MN2. Note that wiring CL is a wiring to which a fixed potential is applied.

[0027] Note that the capacitance value of capacitor 14 (the capacitance value of node MN2) is preferably set to be larger than the gate capacitance of transistor 13 (the capacitance value of node MN1). In the configuration of FIG. 1A, when reading data from semiconductor device 10, data is written back from node MN2 to node MN1 and then read. Therefore, by making the capacitance value of node MN1 smaller than the capacitance value of node MN2, the amount of charge required for writing back data can be reduced.

[0028] One of the source or drain of transistor 13 is connected to wiring RL. The source or the other of the drain of transistor 13 is connected to wiring SL.

[0029] Transistor 12 has a function of controlling whether to transfer the voltage of node MN1 to node MN2 according to the voltage applied to wiring RWL. Further, transistor 12 holds the voltage applied to node MN2 in capacitor 14 according to the voltage applied to wiring RWL. ​It has a function. Transistor 12 functions as a switch whose conduction state or non-conduction state (also referred to as on or off) can be switched.

[0030] As transistor 12, it is preferably composed of a transistor having an oxide semiconductor in a channel formation region (hereinafter referred to as an OS transistor). In the configuration of one aspect of the present invention , by using a memory element having an OS transistor, by taking advantage of the fact that the leakage current (hereinafter referred to as off-current) flowing between the source and drain during the off state is extremely low, a desired voltage can be held in the memory element.

[0031] Transistor 12 is preferably composed of a transistor having an oxide semiconductor in a channel formation region (hereinafter referred to as an OS transistor). In the configuration of one aspect of the present invention, by using an OS transistor for transistor 12, by taking advantage of the fact that the leakage current (hereinafter referred to as off-current) flowing between the source and drain during the non-conduction state (off) is extremely low, a capacitor 14 can hold a charge corresponding to the data written in the semiconductor device 10. That is, in the charge holding circuit 1 5 composed of transistor 12 and capacitor 14, the data written in the semiconductor device 10 can be held for a long time.

[0032] In addition, in the charge holding circuit 15 using an OS transistor, since data can be rewritten and read by charging or discharging the charge, substantially unlimited times of data writing and reading are possible. The charge holding circuit 15 using an OS transistor ​, such as magnetic memory or resistive change memory, without structural changes at the atomic level Therefore, it has excellent rewrite resistance. Also, the charge holding circuit 15 using an OS transistor does not exhibit instability due to an increase in electron trapping centers even during repeated rewrite operations like in flash memory is not recognized.

[0033] Also, the charge holding circuit 15 using an OS transistor can be freely arranged on a circuit using a transistor having a silicon channel formation region (hereinafter referred to as an Si transistor) and the like, so integration can be easily achieved. Also, since the OS transistor can be fabricated using the same manufacturing equipment as the Si transistor , it can be fabricated at low cost.

[0034] Also, in addition to the gate electrode, source electrode, and drain electrode, the OS transistor can be a four-terminal semiconductor element when it includes a back gate electrode. Depending on the voltage applied to the gate electrode or the back gate electrode , the input and output of the signal flowing between the source and the drain can be independently controlled by an electrical circuit network. Therefore, circuit design can be performed with the same concept as that of an LSI . In addition, the OS transistor has better electrical characteristics than the Si transistor under a high-temperature environment . Specifically, since the ratio of the on-current to the off-current is large even at high temperatures such as 125°C or higher and 150°C or lower , a good switching operation can be performed .

[0035] As materials used for the Si transistor, single-crystalline silicon and non-single-crystalline silicon ( for example, polycrystalline silicon, etc.) can be used. Single-crystalline silicon for the Si transistor When used, the current flowing between the source and the drain when turned on (also referred to as the on-current) can be increased. In addition to silicon, as the material of the semiconductor layer, semiconductors such as germanium (Ge) ), compound semiconductors such as GaAs, InP, SiC, ZnSe, GaN, SiGe, etc. can also be used.

[0036] Transistor 11 has a function of controlling whether to transmit the voltage corresponding to the data applied to wiring BL to node MN1 according to the voltage applied to wiring WWL. Transistor 11 can function as a switch whose conduction state or non-conduction state (also referred to as on or off) is switched according to the voltage applied to wiring WWL.

[0037] When an Si transistor is used as the switch, the "conduction state" of the transistor refers to a state where the source electrode and the drain electrode of the transistor can be regarded as being electrically short-circuited. Also, the "non-conduction state" of the transistor refers to a state where the source electrode and the drain electrode of the transistor can be regarded as being electrically interrupted.

[0038] The data applied to wiring BL can be represented as binary data of data '1' or data '0'. Data '1' or data '0' is a signal written by the level of the potential. After data '1' is held at node MN2, it is a potential for flowing a current to such an extent that the data can be read out to transistor 12 by charge distribution from node MN2 to node MN1. Data '0' is a potential for not flowing a current to transistor 12 when charge is distributed from node MN2 to node MN1 after being held at node MN2. ​​​​​​​​​​​

[0039] The transistor 13 has a potential between its source electrode and drain electrode in response to the potential of the node MN1. The wiring RL has a function of controlling the amount of current flowing through it. After being precharged, the potential changes according to the amount of current flowing through transistor 13. The line SL is a line that changes current to the transistor 13 depending on the potential of the node MN1. A potential is applied to control the amount of current flowing through the transistor.

[0040] By using the configuration of FIG. 1A, data can be rewritten and recharged by charging or discharging electric charge. This allows data to be written and read an unlimited number of times. It is possible to discharge the stored charge when reading data, which is called "destruction". Since data can be read without reading, the power required for data refresh is reduced. It is possible to reduce the power consumption for charging and discharging the load.

[0041] In addition, by using the configuration of FIG. 1A, the capacitance value of node MN1 is smaller than the capacitance value of node MN2. Therefore, the amount of charge required to write back data can be reduced. Data can be read out without discharging the stored charge into wiring with a large capacitance. In addition, by increasing the capacitance of node MN2, reliability such as long-term data retention can be improved. This makes it possible to provide a highly reliable semiconductor device.

[0042] FIG. 1B shows a timing chart for explaining an example of the operation of the semiconductor device of FIG. 1A. In FIG. 1B, the wire WWL, the wire RWL, the wire BL, the wire RL, the wire SL, the node MN1 , and the fluctuation of the potential at node MN2 in response to writing and reading of data. is shown in the figure. In FIG. 1B, it is shown in divided periods T1 to T9, and periods T1 to T3 are data writing periods, period T4 is a data holding period, and periods T5 to T9 are data reading periods. Also in FIG. 1B, the data is shown as signals of '1' and '0'. In addition, in the description of the operation example of the semiconductor device 10, the potential of the wiring to which a signal for controlling the conductive state or non-conductive state of the transistor is applied is described as a potential of H level or L level.

[0043] Also, FIGS. 2 to 6 are diagrams for schematically explaining the operation of the semiconductor device 10 in periods T1 to T9 of FIG. 1B. In FIGS. 2 to 6, solid arrows schematically represent the flow of signals input and output between wirings or nodes. In addition, in FIGS. 2 to 6, for easy understanding in the circuit diagram, non-conductive transistors are marked with crosses.

[0044] Period T1 in FIG. 1B is a period for performing a data writing operation. As shown in FIG. 2A, the wiring WWL is set to the H level, the wiring RWL is set to the H level, and the transistors 11 and transistors 12 are made conductive. At the wiring BL, potentials corresponding to the data '1' and '0' are applied, and the potentials are applied to the node MN1 and the node MN2. The wirings RL and SL are at the same potential, and no current flows through the transistor 13.

[0045] Period T2 in FIG. 1B is a period for performing a data writing operation. As shown in FIG. 2B, the potentials of the node MN1 and the node MN2 become potentials corresponding to the data '1' and '0'.

[0046] ​​​​​The period T3 in FIG. 1B is a period for performing a data writing operation. As shown in FIG. 3A . Set the wiring WWL to the H level, the wiring RWL to the L level, turn on the transistor 11, and turn off the transistor 12. At the node MN2, potentials corresponding to the data '1' and '0' are held. At the node MN1, the potentials corresponding to the data '1' and '0' are discharged to the wiring BL and eventually become the L-level potential.

[0047] The period T4 in FIG. 1B is a period for data holding. As shown in FIG. 3B. Set the wiring W WL to the L level, the wiring RWL to the L level, turn off the transistor 11, and turn off the transist or 12. At the node MN2, potentials corresponding to the data '1' and '0' are held. At the node MN1, the potential during the period T3, that is, the L level, is held. The potential of the node MN2 can be made difficult to discharge to the wiring BL by turning off both the transistor 11 and the transistor 12.

[0048] The period T5 in FIG. 1B is a period for performing a data reading operation. As shown in FIG. 4A . Set the wiring WWL to the L level, the wiring RWL to the L level, turn off the transistor 11, and turn off the transistor 12. Precharge the wiring RL to a predetermined potential, for example, the H-level potential (illustrated as precharge in the figure).

[0049] The period T6 in FIG. 1B is a period for performing a data reading operation. As shown in FIG. 4B , set the wiring WWL to the L level, the wiring RWL to the H level, turn off the transistor 11, and turn on the transistor 12. The charge held at the node MN2 is divided to the node MN1 They are arranged such that nodes MN1 and MN2 have potentials corresponding to data '1' and '0'. Since the capacitance value of node MN1 is smaller than that of node MN2, fluctuations in the potential according to the charge distribution can be reduced. In transistor 13, current Iread flows according to the potential of node MN1, that is, the data '1' and '0' held in charge holding circuit 15. If the potential of node MN1 is at the H level, that is, data '1', current Iread is large, and if the potential of node MN1 is at the L level, that is, data '0', it is small. Therefore, if it is data '1', the potential fluctuation of precharged wiring RL is large, and if it is data '0' the potential fluctuation of precharged wiring RL becomes small. The wiring RL precharged in period T5 has its potential fluctuate according to the magnitude of current Iread.

[0050] Period T7 in FIG. 1B is a period for performing a data read operation. As shown in FIG. 5A . In transistor 13, current Iread flows according to the potential of node MN1. If the data of node MN1 is data '1', that is, at the H level potential, current Iread is large . Therefore, the potential fluctuation of precharged wiring RL is large. Conversely, if the data of node MN1 is data '0', that is, at the L level potential, current Iread is small (wiring RL changes to the L level). Therefore, the potential fluctuation of precharged wiring RL is small (wiring RL remains at the H level). Therefore, the data written in semiconductor device 10 can be read out to wiring RL.

[0051] Period T8 in FIG. 1B is a period for performing a data read operation. As shown in FIG. 5B ​​。Set the wiring WWL to the L level, the wiring RWL to the L level, and the transistor 11 to the non-conducting state. Set the transistor 12 to the non-conducting state. The potentials of the node MN1 and the node MN2 become the potentials corresponding to the data '1' and '0'.

[0052] The period T9 in FIG. 1B is a period for performing a data read operation. As shown in FIG. 6. Set the wiring WWL to the H level, the wiring RWL to the L level, the transistor 11 to the conducting state, and the transistor 12 to the non-conducting state. At the node MN2, the potential corresponding to the data '1' and '0' is held. At the node MN1, the potential corresponding to the data '1' and '0' is discharged to the wiring BL. At the node MN1, the potential of the wiring BL, that is, the L level, is obtained. In the transistor 13, the current Iread stops flowing.

[0053] In the configuration of FIG. 1A, by adopting the operation methods of FIGS. 1B, 2 to 6, data can be rewritten and read by charging or discharging the charge, so that substantially unlimited times of data writing and reading are possible. When reading data, it is possible to read the data without discharging the held charge, that is, performing so-called destructive reading, so that the power consumption for charging and discharging the charge required for data refresh can be reduced.

[0054] Also, in the configuration of FIG. 1A, by adopting the operation methods of FIGS. 1B, 2 to 6, since the capacitance value of the node MN1 is smaller than the capacitance value of the node MN2, the amount of charge required for rewriting the data can be reduced. Therefore, the data can be read without discharging the held charge to a wiring or the like having a large capacitance. Also, by increasing the capacitance value of the node MN2, Thus, a semiconductor device with excellent reliability such as long-term data retention can be achieved.

[0055] Note that the transistor 11 can also be an OS transistor, similar to the transistor 12. Since the OS transistor can be freely arranged on a circuit using Si transistors, etc., it can be easily integrated. Also, since the OS transistor can be fabricated using the same manufacturing equipment as Si transistors, it can be manufactured at low cost. In FIG. 7A, the transistors 11A and 12A of the semiconductor device 10A are labeled with the OS symbol to indicate that they are OS transistors. Also, the transistor 13A is labeled with the Si symbol to indicate that it is a Si transistor.

[0056] Note that the transistor 11 can also be a Si transistor, similar to the transistor 13. In FIG. 7B, the transistor 12B of the semiconductor device 10B is labeled with the OS symbol to indicate that it is an OS transistor. Also, the transistors 11B and 13B are labeled with the Si symbol to indicate that they are Si transistors.

[0057] In FIG. 7A, the transistors 11A and 12A of the semiconductor device 10A are illustrated as transistors with a top-gate structure or a bottom-gate structure without a back-gate electrode, but the structures of the transistors 11A and 12A are not limited to this. For example, as in the semiconductor device 10C shown in FIG. 8A, a back-gate connected to the back-gate electrode line BGL Transistors 11C and 12C having electrodes may also be used. The transistor 13C is a Si transistor. By adopting the configuration of FIG. 8A, it becomes easier to externally control electrical characteristics such as the threshold voltage of transistors 11C and 12C.

[0058] Alternatively, as in the semiconductor device 10D illustrated in FIG. 8B, transistors 11D and 12D having a back gate electrode connected to the gate electrode may be used. The transistor 13D is a Si transistor. By adopting the configuration of FIG. 8B, the amount of current flowing through transistors 11 D and 12D can be increased.

[0059] In FIG. 7A, the transistor 13A included in the semiconductor device 10A is illustrated as an n-channel transistor, but the conductivity type of the transistor 13A is not limited thereto. For example, as in the semiconductor device 10E illustrated in FIG. 9A, it can be a p-channel transistor 13E. Transistors 11E and 12E are n-channel OS transistors.

[0060] In FIG. 7B, the transistors 11B and 13B included in the semiconductor device 10B are illustrated as n-channel transistors, but the conductivity types of the transistors 11B and 13B are not limited thereto. For example, as in the semiconductor device 10F illustrated in FIG. 9B, they can be p-channel transistors 11F and 13F. The transistor 12F is an n-channel OS transistor.

[0061] ​​​​​​​In FIG. 7B, a semiconductor device 10B includes a transistor 11B and a transistor 1 Although transistors 11B and 3B are illustrated as transistors of the same conductivity type, The conductivity types of the resistors 13B may be different. For example, as shown in FIG. 9C, As shown in FIG. 1, an n-channel transistor 11G and a p-channel transistor 13G are provided. The transistor 12G is an n-channel OS transistor.

[0062] The semiconductor devices 10 can be arranged in a matrix. The figure shows an example of a configuration in which the semiconductor devices 10 are arranged in a matrix of two rows and two columns. In FIG. 0, the semiconductor device 10 is illustrated as semiconductor devices 10_1 to 10_4. In FIG. 10, the wiring RW is connected to each of the semiconductor devices 10_1 to 10_4. L_1, RWL_2, Wiring WWL_1, WWL_2, Wiring RL_1, RL_2, Wiring BL _1, BL_2, and wiring SL_1, SL_2 are illustrated.

[0063] FIG. 11 is a timing chart for explaining an example of operation in the configuration shown in FIG. The timing chart shown in FIG. 11 overlaps with that shown in FIG. 1B in detail. Therefore, the description will be omitted.

[0064] In the configuration of FIG. 10, the functions of different wiring are shared to reduce the number of wirings. As an example, in FIG. 12, the wirings RL_1 and RL_2 in FIG. By operating the wiring SL_1 and the wiring SL_2 in such a way that they have the same functions, The diagram shows a configuration example in which SL_2 is omitted. In other words, the wiring RL is the same wiring as the wiring SL. By operating it as such, the number of wirings can be reduced.

[0065] FIG. 13 shows a timing chart for explaining an operation example in the configuration illustrated in FIG. 12. The difference between the timing chart shown in FIG. 13 and the timing chart shown in FIG. 11 is that, when writing data to the semiconductor device in the first row, the wiring WWL_2 in the second row, for example, is set to the L level. With this configuration, the current flowing through transistor 13 during data writing can be suppressed. The details of the timing chart for other periods are omitted because they overlap with FIG. 1B. As another example different from FIG. 12, FIG. 14 illustrates a configuration example in which wiring SL_2 is omitted by operating so as to have the functions of wirings SL_1 and SL_2 in FIG. 10. That is, by sharing the wiring SL among a plurality of semiconductor devices, the number of wirings can be reduced. In the configuration described in the above-described embodiments, data can be rewritten and read by charging or discharging an electric charge. Therefore, data can be written and read substantially an unlimited number of times. When reading data, the held electric charge can be discharged, and the data can be read without so-called destructive reading. Therefore, the power consumption for charging and discharging the electric charge required for data refresh can be reduced. Also, in the configuration described in the above-described embodiments, since the capacitance value of node MN1 is smaller than the capacitance value of node MN2, the amount of electric charge required for rewriting data can be reduced.

[0066]

[0067]

[0068] Therefore, data can be read without discharging the stored charge to a wiring or the like having a large capacitance. Also, by increasing the capacitance value of the node MN2, a semiconductor device with excellent reliability such as long-term data retention can be achieved. Further, by increasing the capacitance value of the node MN2, a semiconductor device with excellent reliability such as long-term data retention can be achieved.

[0069] (Embodiment 2) In this embodiment, a cross-sectional configuration example of the semiconductor device described in the above embodiment will be described with reference to the drawings.

[0070] The semiconductor device shown in FIG. 15 includes a transistor 13, a transistor 12, and a capacitor 1 4. FIG. 17A is a cross-sectional view of the transistor 12 in the channel length direction, FIG. 17B is a cross-sectional view of the transistor 12 in the channel width direction, and FIG. 17C is a cross-sectional view of the transistor 1 3 in the channel width direction.

[0071] The transistor 12 is an OS transistor. The transistor 12 has a small off-current. Therefore, the power consumption of the semiconductor device can be reduced.

[0072] The semiconductor device described in this embodiment has a transistor 13, a transistor 12, and a capacitor 14 as shown in FIG. 15. The transistor 12 is provided above the transistor 13 , and the capacitor 14 is provided above the transistor 13 and the transistor 12.

[0073] The transistor 13 is provided on a substrate 311 and includes a semiconductor region 313 composed of a conductor 316, an insulator 315, and a part of the substrate 3 11, a low-resistance region 314a that functions as a source region or a drain region, and a low-resistance region 314b.

[0074] As shown in FIG. 17C, the transistor 13 is formed by forming a top surface of the semiconductor region 313 and a channel The side surfaces in the width direction are covered with the conductor 316 via the insulator 315. By making the resistor 13 a fin type, the effective channel width is increased. The on-characteristics of the transistor 13 can be improved. In addition, the contribution of the electric field of the gate electrode Since the potential can be increased, the off-state characteristics of the transistor 13 can be improved.

[0075] The transistor 13 may be either a p-channel type or an n-channel type.

[0076] The region in which the channel of the semiconductor region 313 is formed and the region in its vicinity, and the source region In the low resistance region 314a and the low resistance region 314b which become the drain region, silicon is It is preferable that the semiconductor material includes a silicon-based semiconductor, and it is preferable that the semiconductor material includes single crystal silicon. are Ge (germanium), SiGe (silicon germanium), and GaAs (gallium arsenide). Alternatively, the insulating layer 12 may be made of a material having a thickness of 100 nm, such as gallium aluminum arsenide (GaAlAs), or the like. The effective mass of silicon was controlled by applying stress to the crystal lattice and changing the lattice spacing. Alternatively, the transistor 13 may be formed by using GaAs and GaAlAs. HEMT (High Electron Mobility Transistor) You may do so.

[0077] The low resistance region 314a and the low resistance region 314b are semiconductor regions applied to the semiconductor region 313. In addition to the material, elements that impart n-type conductivity, such as arsenic or phosphorus, or p-type conductivity, such as boron, are added. Contains elements that impart properties.

[0078] The conductor 316 functioning as a gate electrode is a semiconductor material such as silicon containing an element that imparts n-type conductivity such as arsenic or phosphorus, or an element that imparts p-type conductivity such as boron, a metal material, an alloy material, or a conductive material such as a metal oxide material. Since the work function is determined by the material of the conductor, the material of the conductor can be selected to adjust the threshold voltage of the transistor. Specifically, it is preferable to use a material such as titanium nitride or tantalum nitride for the conductor. Further, in order to achieve both conductivity and embedding property, it is preferable to use a metal material such as tungsten or aluminum as a laminate for the conductor, and it is particularly preferable to use tungsten from the viewpoint of heat resistance. The conductor 316 functioning as a gate electrode can be made of a semiconductor material such as silicon containing an element that imparts n-type conductivity such as arsenic or phosphorus, or an element that imparts p-type conductivity such as boron, a metal material, an alloy material, or a conductive material such as a metal oxide material.

[0079] Since the work function is determined by the material of the conductor, the material of the conductor can be selected to adjust the threshold voltage of the transistor. Specifically, it is preferable to use a material such as titanium nitride or tantalum nitride for the conductor. Further, in order to achieve both conductivity and embedding property, it is preferable to use a metal material such as tungsten or aluminum as a laminate for the conductor, and it is particularly preferable to use tungsten from the viewpoint of heat resistance. The conductor 316 functioning as a gate electrode can be made of a semiconductor material such as silicon containing an element that imparts n-type conductivity such as arsenic or phosphorus, or an element that imparts p-type conductivity such as boron, a metal material, an alloy material, or a conductive material such as a metal oxide material. Since the work function is determined by the material of the conductor, the material of the conductor can be selected to adjust the threshold voltage of the transistor. Specifically, it is preferable to use a material such as titanium nitride or tantalum nitride for the conductor. Further, in order to achieve both conductivity and embedding property, it is preferable to use a metal material such as tungsten or aluminum as a laminate for the conductor, and it is particularly preferable to use tungsten from the viewpoint of heat resistance. The conductor 316 functioning as a gate electrode can be made of a semiconductor material such as silicon containing an element that imparts n-type conductivity such as arsenic or phosphorus, or an element that imparts p-type conductivity such as boron, a metal material, an alloy material, or a conductive material such as a metal oxide material. Since the work function is determined by the material of the conductor, the material of the conductor can be selected to adjust the threshold voltage of the transistor. Specifically, it is preferable to use a material such as titanium nitride or tantalum nitride for the conductor. Further, in order to achieve both conductivity and embedding property, it is preferable to use a metal material such as tungsten or aluminum as a laminate for the conductor, and it is particularly preferable to use tungsten from the viewpoint of heat resistance.

[0080] Note that the transistor 13 shown in FIG. 15 is an example and is not limited to its structure, and an appropriate transistor may be used according to the circuit configuration and driving method. For example, when the semiconductor device is a unipolar circuit consisting only of OS transistors, as shown in FIG. 16, the configuration of the transistor 13 may be the same as that of the transistor 12 which is an OS transistor. Details of the transistor 12 will be described later. In this specification and the like, a unipolar circuit refers to, for example, a circuit in which all transistors are transistors of the same polarity. For example, a circuit in which all transistors are n-channel type transistors can be said to be a unipolar circuit. Note that the transistor 13 shown in FIG. 15 is an example and is not limited to its structure, and an appropriate transistor may be used according to the circuit configuration and driving method. For example, when the semiconductor device is a unipolar circuit consisting only of OS transistors, as shown in FIG. 16, the configuration of the transistor 13 may be the same as that of the transistor 12 which is an OS transistor. Details of the transistor 12 will be described later. Note that the transistor 13 shown in FIG. 15 is an example and is not limited to its structure, and an appropriate transistor may be used according to the circuit configuration and driving method. For example, when the semiconductor device is a unipolar circuit consisting only of OS transistors, as shown in FIG. 16, the configuration of the transistor 13 may be the same as that of the transistor 12 which is an OS transistor. Details of the transistor 12 will be described later. Note that the transistor 13 shown in FIG. 15 is an example and is not limited to its structure, and an appropriate transistor may be used according to the circuit configuration and driving method. For example, when the semiconductor device is a unipolar circuit consisting only of OS transistors, as shown in FIG. 16, the configuration of the transistor 13 may be the same as that of the transistor 12 which is an OS transistor. Details of the transistor 12 will be described later.

[0081] In this specification and the like, a unipolar circuit refers to, for example, a circuit in which all transistors are transistors of the same polarity. For example, a circuit in which all transistors are n-channel type transistors can be said to be a unipolar circuit. In this specification and the like, a unipolar circuit refers to, for example, a circuit in which all transistors are transistors of the same polarity. For example, a circuit in which all transistors are n-channel type transistors can be said to be a unipolar circuit. In this specification and the like, a unipolar circuit refers to, for example, a circuit in which all transistors are transistors of the same polarity. For example, a circuit in which all transistors are n-channel type transistors can be said to be a unipolar circuit.

[0082] Over the transistor 13, insulators 320, 322, 324, and 326 are sequentially laminated and provided. Over the transistor 13, insulators 320, 322, 324, and 326 are sequentially laminated and provided.

[0083] As the insulators 320, 322, 324, and 326, for example, oxidation silicon, silicon oxynitride, silicon nitride oxide, silicon nitride, aluminum oxide, aluminum oxynitride, aluminum nitride oxide, aluminum nitride, etc. may be used.

[0084] In addition, in this specification, etc., silicon oxynitride refers to a material whose oxygen content is higher than its nitrogen content in terms of its composition, and silicon nitride oxide refers to a material whose nitrogen content is higher than its oxygen content in terms of its composition. Also, in this specification, etc., aluminum oxynitride refers to a material whose oxygen content is higher than its nitrogen content in terms of its composition, and aluminum nitride oxide refers to a material whose nitrogen content is higher than its oxygen content in terms of its composition. In addition, in this specification, etc., silicon oxynitride refers to a material whose oxygen content is higher than its nitrogen content in terms of its composition, and silicon nitride oxide refers to a material whose nitrogen content is higher than its oxygen content in terms of its composition. Also, in this specification, etc., aluminum oxynitride refers to a material whose oxygen content is higher than its nitrogen content in terms of its composition, and aluminum nitride oxide refers to a material whose nitrogen content is higher than its oxygen content in terms of its composition. In addition, in this specification, etc., aluminum oxynitride refers to a material whose oxygen content is higher than its nitrogen content in terms of its composition, and aluminum nitride oxide refers to a material whose nitrogen content is higher than its oxygen content in terms of its composition. In addition, in this specification, etc., aluminum oxynitride refers to a material whose oxygen content is higher than its nitrogen content in terms of its composition, and aluminum nitride oxide refers to a material whose nitrogen content is higher than its oxygen content in terms of its composition. In addition, in this specification, etc., aluminum oxynitride refers to a material whose oxygen content is higher than its nitrogen content in terms of its composition, and aluminum nitride oxide refers to a material whose nitrogen content is higher than its oxygen content in terms of its composition.

[0085] The insulator 322 may have a function as a planarization film that planarizes the step generated by the transistor 13 or the like provided below it. For example, the upper surface of the insulator 322 may be planarized by a planarization process using a chemical mechanical polishing (CMP) method or the like to enhance flatness. The insulator 322 may have a function as a planarization film that planarizes the step generated by the transistor 13 or the like provided below it. For example, the upper surface of the insulator 322 may be planarized by a planarization process using a chemical mechanical polishing (CMP) method or the like to enhance flatness. The insulator 322 may have a function as a planarization film that planarizes the step generated by the transistor 13 or the like provided below it. For example, the upper surface of the insulator 322 may be planarized by a planarization process using a chemical mechanical polishing (CMP) method or the like to enhance flatness. The insulator 322 may have a function as a planarization film that planarizes the step generated by the transistor 13 or the like provided below it. For example, the upper surface of the insulator 322 may be planarized by a planarization process using a chemical mechanical polishing (CMP) method or the like to enhance flatness.

[0086] In addition, for the insulator 324, it is preferable to use a film having a barrier property such that hydrogen and impurities do not diffuse from the substrate 311 or the transistor 13 or the like into the region where the transistor 12 is provided. In addition, for the insulator 324, it is preferable to use a film having a barrier property such that hydrogen and impurities do not diffuse from the substrate 311 or the transistor 13 or the like into the region where the transistor 12 is provided. In addition, for the insulator 324, it is preferable to use a film having a barrier property such that hydrogen and impurities do not diffuse from the substrate 311 or the transistor 13 or the like into the region where the transistor 12 is provided.

[0087] As an example of a film having a barrier property against hydrogen, for example, silicon nitride formed by CVD method can be used. Here, when hydrogen diffuses into a semiconductor element having an oxide semiconductor such as the transistor 12, the characteristics of the semiconductor element may deteriorate. Therefore As an example of a film having a barrier property against hydrogen, for example, silicon nitride formed by CVD method can be used. Here, when hydrogen diffuses into a semiconductor element having an oxide semiconductor such as the transistor 12, the characteristics of the semiconductor element may deteriorate. Therefore As an example of a film having a barrier property against hydrogen, for example, silicon nitride formed by CVD method can be used. Here, when hydrogen diffuses into a semiconductor element having an oxide semiconductor such as the transistor 12, the characteristics of the semiconductor element may deteriorate. Therefore , it is preferable to use a film that suppresses the diffusion of hydrogen between the transistor 12 and the transistor 13. Specifically, the film that suppresses the diffusion of hydrogen is a film with a small amount of hydrogen desorption.

[0088] The amount of hydrogen desorption can be analyzed, for example, using temperature-programmed desorption gas analysis (TDS). For example, the amount of hydrogen desorption of the insulator 324 is such that in the TDS analysis, in the range where the surface temperature of the film is from 50 °C to 500 °C, the desorption amount converted to hydrogen atoms per unit area of the insulator 324 is converted per unit area, and is 10×10 15 atoms / cm 2 or less, preferably 5×10 15 at oms / cm 2 or less.

[0089] Note that the insulator 326 preferably has a lower dielectric constant than the insulator 324. For example, the relative dielectric constant of the insulator 326 is preferably less than 4, more preferably less than 3. Also, for example, the relative dielectric constant of the insulator 326 is preferably 0.7 times or less, more preferably 0.6 times or less, of the relative dielectric constant of the insulator 324. By using a material with a low dielectric constant as the interlayer film, the parasitic capacitance generated between the wirings can be reduced.

[0090] In addition, a capacitor 14, or a conductor 328 connected to the transistor 12, and a conductor 330, etc. are embedded in the insulator 320, the insulator 322, the insulator 324, and the insulator 326. Note that the conductor 328 and the conductor 330 have functions as plugs or wirings. Also, conductors having functions as plugs or wirings may be given the same reference numeral when summarizing a plurality of structures. Further, in this specification, etc., a wiring and a plug connected to the wiring ​​​​​​​​They may be integrated. That is, when a part of the conductor functions as a wiring, and when a part of the conductor functions as a plug. There are also cases.

[0091] As materials for each plug and wiring (such as conductor 328 and conductor 330), conductive materials such as metal materials, alloy materials, metal nitride materials, or metal oxide materials can be used alone or in layers. It is preferable to use high melting point materials such as tungsten and molybdenum that can achieve both heat resistance and conductivity, and it is more preferable to use tungsten. Or, it is preferable to form it with a low resistance conductive material such as aluminum or copper. By using a low resistance conductive material, the wiring resistance can be reduced. A wiring layer may be provided on the insulator 326 and the conductor 330. For example, in FIG. 15, the insulator 350, the insulator 352, and the insulator 354 are laminated in order. In addition, a conductor 356 is formed on the insulator 350, the insulator 352, and the insulator 354. The conductor 356 has a function as a plug connected to the transistor 13 or a wiring. Note that the conductor 356 can be provided using the same material as the conductor 328 or the conductor 330.

[0092] Note that, for example, the insulator 350 is preferably an insulator having a barrier property against hydrogen, similar to the insulator 324. Also, the conductor 356 preferably includes a conductor having a barrier property against hydrogen. In particular, a conductor having a barrier property against hydrogen is formed in an opening provided in the insulator 350 having a barrier property against hydrogen. With this configuration, the transistor 13 and the transistor 12 can be separated by a barrier layer.

[0093] ​ Diffusion of hydrogen from transistor 13 to transistor 12 can be suppressed.

[0094] As the conductor having barrier properties against hydrogen, for example, tantalum nitride or the like may be used. Also, by laminating tantalum nitride and tungsten having high conductivity, diffusion of hydrogen from transistor 13 can be suppressed while maintaining the conductivity as wiring. In this case, it is preferable that the tantalum nitride layer having barrier properties against hydrogen is in contact with the insulator 350 having barrier properties against hydrogen.

[0095] A wiring layer may be provided on the insulator 354 and the conductor 356. For example, in FIG. 15, the insulator 360, the insulator 362, and the insulator 364 are laminated and provided in order. Also, the conductor 366 is formed on the insulator 360, the insulator 362, and the insulator 364. The conductor 366 has a function as a plug or wiring. The conductor 366 can be provided using the same material as the conductor 328 or the conductor 330.

[0096] For example, it is preferable to use an insulator having barrier properties against hydrogen for the insulator 360, similar to the insulator 324. Also, the conductor 366 preferably includes a conductor having barrier properties against hydrogen. In particular, a conductor having barrier properties against hydrogen is formed in the opening provided in the insulator 360 having barrier properties against hydrogen. With this configuration, the transistor 13 and the transistor 12 can be separated by the barrier layer, and diffusion of hydrogen from the transistor 13 to the transistor 12 can be suppressed.

[0097] A wiring layer may be provided on the insulator 364 and the conductor 366. For example, in FIG. 15 the insulators 370, 372, and 374 are sequentially laminated and provided. Also a conductor 376 is formed on the insulators 370, 372, and 374. The conductor 376 has a function as a plug or wiring. Note that the conductor 376 can be provided using the same material as the conductor 328 or the conductor 330.

[0098] Note that, for example, the insulator 370 preferably uses an insulator having a barrier property against hydrogen, similar to the insulator 324. Also, the conductor 376 preferably includes a conductor having a barrier property against hydrogen. In particular, a conductor having a barrier property against hydrogen is formed in an opening provided in the insulator 370 having a barrier property against hydrogen. With this configuration the transistor 13 and the transistor 12 can be separated by a barrier layer, and diffusion of hydrogen from the transistor 13 to the transistor 12 can be suppressed.

[0099] A wiring layer may be provided on the insulator 374 and the conductor 376. For example, in FIG. 15 the insulators 380, 382, and 384 are sequentially laminated and provided. Also a conductor 386 is formed on the insulators 380, 382, and 384. The conductor 386 has a function as a plug or wiring. Note that the conductor 386 can be provided using the same material as the conductor 328 or the conductor 330.

[0100] Note that, for example, the insulator 380 preferably uses an insulator having a barrier property against hydrogen, similar to the insulator 324. Also, the conductor 386 preferably includes a conductor having a barrier property against hydrogen. ​ Preferably, it includes a conductor. In particular, a conductor having a barrier property against hydrogen is formed in an opening provided in the insulator 380 having a barrier property against hydrogen. With this configuration, the transistor 13 and the transistor 12 can be separated by a barrier layer, and diffusion of hydrogen from the transistor 13 to the transistor 12 can be suppressed.

[0101] In the above, the wiring layer including the conductor 356, the wiring layer including the conductor 366, the wiring layer including the conductor 376, and the wiring layer including the conductor 386 have been described. However, the semiconductor device according to the present embodiment is not limited to this. The number of wiring layers similar to the wiring layer including the conductor 356 may be three or less, or may be five or more.

[0102] On the insulator 384, an insulator 510, an insulator 512, an insulator 514, and an insulator 516 are laminated in this order. Any of the insulator 510, the insulator 512, the insulator 514, and the insulator 516 is preferably made of a material having a barrier property against oxygen and hydrogen.

[0103] For example, for the insulator 510 and the insulator 514, it is preferable to use a film having a barrier property so that hydrogen and impurities do not diffuse from the substrate 311 or the like or from the region where the transistor 13 is provided to the region where the transistor 12 is provided. Therefore, it is preferable to use the same material as the insulator 324.

[0104] As an example of a film having a barrier property against hydrogen, silicon nitride formed by CVD can be used. Here, water is added to a semiconductor element having an oxide semiconductor such as the transistor 12. ​​​​​​​​​​​​​ When elements diffuse, the characteristics of the semiconductor device may deteriorate. Therefore, it is preferable to use a film that suppresses the diffusion of hydrogen between the transistor 12 and the transistor 13. Specifically, the film that suppresses the diffusion of hydrogen is a film with a small amount of hydrogen desorption.

[0105] Also, as a film having barrier properties against hydrogen, for example, for the insulator 510 and the insulator 5 14, it is preferable to use metal oxides such as aluminum oxide, hafnium oxide, and tantalum oxide.

[0106] In particular, aluminum oxide has a high blocking effect that does not allow the film to permeate both oxygen and impurities such as hydrogen and moisture that are factors causing fluctuations in the electrical characteristics of the transistor. Therefore, aluminum oxide can prevent the mixing of impurities such as hydrogen and moisture into the transistor 12 during and after the manufacturing process of the transistor. Also, it can suppress the release of oxygen from the metal oxide constituting the transistor 12. Therefore, it is suitable to be used as a protective film for the transistor 12.

[0107] Also, for example, for the insulator 512 and the insulator 516, the same materials as those of the insulator 320 can be used. Also, by applying a material with a relatively low dielectric constant to these insulators, the parasitic capacitance generated between the wirings can be reduced. For example, a silicon oxide film, a silicon oxynitride film, or the like can be used as the insulator 512 and the insulator 516.

[0108] Also, for the insulator 510, the insulator 512, the insulator 514, and the insulator 516, the conductor 5 18 and conductors (for example, the conductor 503) constituting the transistor 12 are embedded, etc.​​​​​​​​​ is provided. The conductor 518 has a function as a plug connected to the capacitor 14 or the transistor 13, or as a wiring. The conductor 518 can be provided using the same material as the conductor 328 or the conductor 330.

[0109] In particular, the conductor 518 in the region in contact with the insulator 510 and the insulator 514 is preferably a conductor having a barrier property against oxygen, hydrogen, and water. With this configuration, the transistor 13 and the transistor 12 can be separated by a layer having a barrier property against oxygen, hydrogen, and water, and the diffusion of hydrogen from the transistor 13 to the transistor 12 can be suppressed.

[0110] The transistor 12 is provided above the insulator 516.

[0111] As shown in FIGS. 17A and 17B, the transistor 12 includes a conductor 503 arranged to be embedded in the insulator 514 and the insulator 516, an insulator 520 arranged on the insulator 516 and the conductor 503, an insulator 522 arranged on the insulator 520, an insulator 524 arranged on the insulator 522, an oxide 530a arranged on the insulator 524, an oxide 530b arranged on the oxide 530a, conductors 542a and 542b arranged separately from each other on the oxide 530b, an insulator 580 arranged on the conductors 542a and 542b and having an opening formed by overlapping between the conductor 542a and the conductor 542b, an oxide 530c arranged on the bottom surface and the side surface of the opening, an insulator 550 arranged on the formation surface of the oxide 530c, and a conductor 560 arranged on the formation surface of the insulator 550. ​​​​​​​​​​​​​​​

[0112] As shown in FIGS. 17A and 17B, the oxide 530a, the oxide 530b, the conductor 5 It is preferable to dispose an insulator 544 between the conductor 542a and the insulator 580. As shown in FIGS. 17A and 17B, the conductor 560 is disposed inside the insulator 550. and a conductor 560a provided so as to be embedded inside the conductor 560a. It is preferable that the conductive material 560b is provided. Also, as shown in FIG. 17A and FIG. 17B, An insulator 574 may be disposed on the insulator 580, the conductor 560, and the insulator 550. preferable.

[0113] In the following, the oxide 530a, the oxide 530b, and the oxide 530c are collectively referred to as oxides 530a, 530b, and 530c. This is sometimes called oxide 530.

[0114] In the transistor 12, the region where the channel is formed and the vicinity thereof are oxidized. 5 shows a structure in which three layers of a substrate 530a, an oxide 530b, and an 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, a two-layer structure of oxide 530b and oxide 530c, or In addition, the transistor 12 may have a stacked structure of four or more layers. Although 560 is shown as a two-layer laminate structure, the present invention is not limited to this. For example, the conductor 560 may have a single layer structure, or a laminated structure of three or more layers. The transistor 12 shown in FIGS. 15, 16, 17A, and 17B is an example. There are no limitations on the structure, and appropriate transistors may be used depending on the circuit configuration and driving method.

[0115] Here, the conductor 560 functions as the gate electrode of the transistor 12, and the conductors 542 a and 542b function as source electrodes or drain electrodes, respectively. As described above, the conductor 560 is formed so as to be embedded in the opening of the insulator 580 and in the region sandwiched between the conductors 542a and 542b. The arrangement of the conductor 560, the conductor 542a, and the conductor 542b is selected self-aligned with respect to the opening of the insulator 580. That is, in the transistor 12, the gate electrode can be arranged self-aligned between the source electrode and the drain electrode. Therefore, the conductor 560 can be formed without providing an alignment margin, so that the occupied area of the transistor 12 can be reduced. As a result, miniaturization and high integration of the semiconductor device can be achieved.

[0116] Furthermore, since the conductor 560 is formed self-aligned in the region between the conductors 542a and 542b, the conductor 560 does not have a region overlapping with the conductor 542a or the conductor 542b. As a result, the parasitic capacitance formed between the conductor 560 and the conductors 542a and 542b can be reduced. Therefore, the switching speed of the transistor 12 can be improved, and high frequency characteristics can be achieved.

[0117] The conductor 560 may function as a first gate (also referred to as a top gate) electrode. Also, the conductor 503 may function as a second gate (also referred to as a bottom gate) electrode. In that case, the threshold voltage of the transistor 12 is controlled by changing the potential applied to the conductor 503 independently without linking it to the potential applied to the conductor 560. is possible. In particular, by applying a negative potential to the conductor 503, the threshold voltage of the transistor 12 can be made greater than 0 V, and the off-current can be reduced. Therefore, applying a negative potential to the conductor 503 can make the drain current smaller when the potential applied to the conductor 560 is 0 V than when no potential is applied.

[0118] The conductor 503 is arranged so as to have a region overlapping with the oxide 530 and the conductor 560. Thereby, when a potential is applied to the conductor 560 and the conductor 503, the electric field generated from the conductor 560 and the electric field generated from the conductor 503 are connected, and the channel formation region formed in the oxide 530 can be covered. In this specification and the like, the structure of a transistor in which a channel formation region is electrically surrounded by the electric fields of the first gate electrode and the second gate electrode is referred to as a surrounded channel (s-channel) structure.

[0119] Further, the conductor 503 has the same configuration as the conductor 518, and a conductor 503a is formed in contact with the inner walls of the openings of the insulator 514 and the insulator 516, and a conductor 503b is further formed inside. Note that, in the transistor 12, a configuration in which the conductor 503a and the conductor 503b are laminated is shown, but the present invention is not limited to this. For example, the conductor 503 may be provided in a single-layer or a laminated structure of three or more layers.

[0120] Here, the conductor 503a preferably uses a conductive material having a function of suppressing the diffusion of impurities such as hydrogen atoms, hydrogen molecules, water molecules, and copper atoms (the above impurities are difficult to permeate). Alternatively, it has a function of suppressing the diffusion of oxygen (for example, at least one of oxygen atoms, oxygen molecules, etc.). ​​​​​​​​​​​ It is preferable to use a conductive material having (the above oxygen is less permeable.) In the present specification and the like, the function of suppressing the diffusion of impurities or oxygen means the function of suppressing the diffusion of any one or all of the above impurities or the above oxygen.

[0121] For example, since the conductor 503a has the function of suppressing the diffusion of oxygen, it is possible to suppress the oxidation of the conductor 50 3b and the decrease in conductivity.

[0122] Further, when the conductor 503 also serves as a wiring function, it is preferable to use a highly conductive material mainly composed of tungsten, copper or aluminum for the conductor 503b. In that case, the conductor 503a does not necessarily have to be provided. Although the conductor 503b is shown as a single layer it may also have a laminated structure. For example, it may be a laminate of titanium or titanium nitride and the above conductive material

[0123] The insulators 520, 522, and 524 have the function as a second gate insulating film

[0124] Here, for the insulator 524 in contact with the oxide 530, it is preferable to use an insulator containing more oxygen than oxygen satisfying the stoichiometric composition. That is, it is preferable that an excess oxygen region is formed in the insulator 524. By providing such an insulator containing excess oxygen in contact with the oxide 530, the oxygen deficiency in the oxide 530 can be reduced, and the reliability of the transistor 12 can be improved.

[0125] Specific examples of the insulator having an excess oxygen region include an acid from which a part of oxygen desorbs by heating ​​​​​​It is preferable to use an oxide material. An oxide that desorbs oxygen upon heating is an oxide film in which the desorption amount of oxygen in terms of oxygen atoms is 1.0×10 or more, preferably 1.0 ×10 18 atoms / cm 3 or more, more preferably 2.0×10 ×10 19 atoms / cm 3 or more, still more preferably 3.0×10 19 atoms / c m 3 or more, as determined by TDS (Thermal Desorption Spectroscopy) analysis. Note that 20 atoms / cm 3 the surface temperature of the film during the above TDS analysis is preferably in the range of 100°C or higher and 700°C or lower, or 100 °C or higher and 400°C or lower.

[0126] In addition, the insulator having the above excess oxygen region and the oxide 530 may be subjected to one or more of heat treatment, microwave treatment, or RF treatment in contact with each other. By performing such treatment, water or hydrogen in the oxide 530 can be removed. For example, in the oxide 530, a reaction occurs in which the bond of VoH is cleaved, in other words, a reaction of "V H→V +H" occurs, enabling dehydrogenation. Part of the hydrogen generated at this time may combine with oxygen to form H2O and be removed from the oxide 530 or the insulator near the oxide 530. In addition, part of the hydrogen may diffuse or be trapped (also referred to as gettering) by the conductor 542. O H→V O +H

[0127] The above microwave treatment is, for example, a device having a power source for generating high-density plasma Alternatively, it is preferable to use an apparatus having a power source for applying RF to the substrate side. For example, oxygen By using a gas containing oxygen and high-density plasma, high-density oxygen radicals are generated. In addition, by applying RF to the substrate side, high density plasma is generated. The oxygen radicals are efficiently introduced into the oxide 530 or into the insulator near the oxide 530. The microwave treatment can be carried out at a pressure of 133 Pa or more, preferably 2 The pressure should be 00 Pa or more, and more preferably 400 Pa or more. The gases introduced into the apparatus are, for example, oxygen and argon, and the oxygen flow ratio (O / (O2+Ar)) is set to 50% or less, preferably 10% or more and 30% or less.

[0128] In addition, during the manufacturing process of the transistor 12, the surface of the oxide 530 is exposed. It is preferable to perform a heat treatment. The heat treatment is performed at a temperature of, for example, 100° C. or higher and 450° C. or lower. More preferably, the heat treatment is carried out at a temperature of 350° C. to 400° C. In addition, the heat treatment may be carried out in a nitrogen gas atmosphere or in a nitrogen atmosphere. or an atmosphere of inert gas, or an atmosphere of oxidizing gas of 10 ppm or more, 1% or more, or 10% For example, the heat treatment is preferably performed in an oxygen atmosphere. By supplying oxygen to the oxide 530, oxygen vacancies (V O ) can be reduced. The heat treatment may be carried out under reduced pressure or in an atmosphere of nitrogen gas or an inert gas. After heat treatment in this atmosphere, oxidizing gas is added at a concentration of 10 ppm or more to compensate for the oxygen that has been removed. Alternatively, the treatment may be carried out in an atmosphere containing 1% or more of an oxidizing gas, or 10 ppm or more of an oxidizing gas. After heat treatment in an atmosphere containing 1% or more, or 10% or more, nitrogen gas or Alternatively, heat treatment may be performed in an inert gas atmosphere.

[0129] Note that by subjecting the oxide 530 to an oxygen addition treatment, oxygen vacancies in the oxide 530 can be repaired with the supplied oxygen, in other words, the reaction “V +O→null” can be promoted. O Furthermore, by reacting the hydrogen remaining in the oxide 530 with the oxygen supplied to the oxide 530, the hydrogen can be removed (dehydrated) as H2O. As a result, it is possible to suppress the recombination of the hydrogen remaining in the oxide 530 with oxygen vacancies to form V H. O H. formed.

[0130] When the insulator 524 has an excess oxygen region, it is preferable that the insulator 522 has a function of suppressing the diffusion of oxygen (e.g., oxygen atoms, oxygen molecules, etc.) (the oxygen is difficult to permeate). Preferably.

[0131] Since the insulator 522 has a function of suppressing the diffusion of oxygen and impurities, it is preferable that the oxygen contained in the oxide 530 does not diffuse to the insulator 520 side. Also, it is possible to suppress the conductor 503 from reacting with the oxygen contained in the insulator 524 and the oxide 530.

[0132] The insulator 522 is preferably used as a single layer or a laminate of insulators containing so-called high-k materials such as aluminum oxide, hafnium oxide, an oxide containing aluminum and hafnium (hafnium aluminate), tantalum oxide, zirconium oxide, lead zirconate titanate (PZT), strontium titanate (SrTiO3), or (Ba ,Sr)TiO3 (BST), etc. As the miniaturization and high integration of transistors progress, the gate insulating film ,Sr)TiO3 (BST), etc. As the miniaturization and high integration of transistors progress, the gate insulating film Thinning may cause problems such as leakage current. When functioning as a gate insulating film By using a high-k material for the insulator, while maintaining the physical film thickness, during transistor operation it is possible to reduce the gate potential.

[0133] In particular, it has a function of suppressing the diffusion of impurities and oxygen (the above oxygen is difficult to permeate) It is preferable to use an insulator containing one or both of the oxides of aluminum and hafnium, which are insulating materials. As an insulator containing one or both of the oxides of aluminum and hafnium, aluminum oxide hafnium oxide, or an oxide containing aluminum and hafnium (hafnium aluminate), etc. are preferably used. When the insulator 522 is formed using such a material the insulator 522 functions as a layer that suppresses the release of oxygen from the oxide 530 and the mixing of impurities such as hydrogen from the peripheral portion of the transistor 12 into the oxide 530.

[0134] Alternatively, for example, aluminum oxide, bismuth oxide, germanium oxide, niobium oxide, silicon oxide, titanium oxide, tungsten oxide, yttrium oxide, zirconium oxide may be added to these insulators. Or these insulators may be nitrided. Silicon oxide, silicon oxynitride, or silicon nitride may be laminated on the above insulators and used.

[0135]

[0136] Also, the insulator 520 is preferably thermally stable. For example, silicon oxide and silicon oxynitride are suitable because they are thermally stable. Also, by combining a high-k material insulator with silicon oxide or silicon oxynitride, an insulator 520 with a laminated structure that is thermally stable and has a high relative permittivity can be obtained.

[0136]

[0136] In the transistors 12 of FIGS. 17A and 17B, insulator 520, insulator 522, and insulator 524 are shown as a second gate insulating film having a three-layer stacked structure, but the second gate insulating film may have a single-layer, two-layer, or four-layer or more stacked structure. In that case, it is not limited to a stacked structure made of the same material, and a stacked structure made of different materials may also be used. .

[0137] It is preferable to use a metal oxide that functions as an oxide semiconductor for the oxide 530 including the channel formation region in the transistor 12. For example, as the oxide 530, an In-M-Zn oxide (element M is one or more selected from aluminum, gallium, yttrium, copper, vanadium, beryllium, boron, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, or magnesium, etc.) or the like of a metal oxide may be used. In particular, the In-M-Zn oxide applicable as the oxide 530 is CAAC-OS (C-Axis Aligned Crystal Oxide Semiconductor), CAC-OS (Clustered-Aligned Composite Oxide Semiconductor). It is preferably. Further, an In-Ga oxide or an In-Zn oxide may be used as the oxide 530. CAAC-OS and CAC-OS will be described later. When it is desired to increase the on-current of the transistor 12, it is preferable to use an In-Zn oxide for the oxide 530. When an In-Zn oxide is used for the oxide 530, for example, an In-Zn oxide is used for the oxide 530a, and an In-M- for the oxide 530b and the oxide 530c. is preferably used. oxide may also be used. When an In-Zn oxide is used for the oxide 530, for example, an In-Zn oxide is used for the oxide 530a, and an In-M- oxide is used for the oxide 530b and the oxide 530c. When an In-Zn oxide is used for the oxide 530, for example, an In-Zn oxide is used for the oxide 530a, and an In-M- A stacked structure using a zinc oxide, or an In-M-Zn oxide is used for the oxide 530a, and an In-Zn oxide is used for either one of the oxide 530b and the oxide 530c. Examples thereof include a stacked structure.

[0138] In addition, for the transistor 12, it is preferable to use a metal oxide with a low carrier concentration. When reducing the carrier concentration of the metal oxide, the impurity concentration in the metal oxide may be reduced, and the density of defect levels may be reduced. In this specification and the like, a low impurity concentration and a low density of defect levels are referred to as high-purity intrinsic or substantially high-purity intrinsic. Note that impurities in the metal oxide include, for example, hydrogen, nitrogen, alkali metals, alkaline earth metals, iron, nickel, silicon, and the like.

[0139] In particular, hydrogen contained in the metal oxide may react with oxygen bonded to a metal atom to form water, and thus oxygen vacancies may be formed in the metal oxide. Further, when hydrogen enters the oxygen vacancies in the oxide 530, oxygen vacancies and hydrogen may combine to form V O H. V O H may function as a donor, and electrons that are carriers may be generated. Further, a part of hydrogen may combine with oxygen bonded to a metal atom to generate electrons that are carriers. Therefore, a transistor using a metal oxide containing a large amount of hydrogen is likely to have normally-on characteristics. In addition, since hydrogen in the metal oxide is likely to move due to stress such as heat and an electric field, if a large amount of hydrogen is contained in the metal oxide, the reliability of the transistor may deteriorate. In one aspect of the present invention, V H in the oxide 530 is reduced as much as possible, and high-purity intrinsic or substantially high-purity intrinsic is achieved. O ​​​It is preferably substantially highly pure and genuine. Thus, for O obtaining a metal oxide with sufficiently reduced V H, it is necessary to remove impurities such as moisture and hydrogen in the metal oxide (which may be described as dehydration and dehydrogenation treatment), and supply oxygen to the metal oxide to compensate for oxygen vacancies O (which may be described as oxygen addition treatment). It is important that impurities such as V H are sufficiently reduced. By using a metal oxide with sufficiently reduced impurities in the channel formation region of a transistor, stable electrical characteristics

[0140] can be imparted. Defects in which hydrogen enters oxygen vacancies can function as donors in the metal oxide. However, it is difficult to quantitatively evaluate such defects. Therefore, in a metal oxide, it may be evaluated by carrier concentration rather than donor concentration. Thus, in this specification and the like, as a parameter of the metal oxide, carrier concentration assuming a state where no electric field is applied may be used instead of donor concentration. That is, the "carrier concentration" described in this specification and the like may sometimes be paraphrased as "donor concentration".

[0141] Therefore, when using a metal oxide for the oxide 530, it is preferable that hydrogen in the metal oxide is reduced as much as possible. Specifically, in the metal oxide, by secondary ion mass spectrometry (SIMS: Secondary Ion Mass Spectrometry), the hydrogen concentration obtained is less than 1×10 (SIMS: Secondary Ion Mass Spectrometry), the hydrogen concentration obtained is less than 1×10 atoms / cm 20 atoms / cm 3 less than, preferably less than 1×10 19 atoms / cm 3 less than, more preferably less than 5×10 18 atoms / cm 3 less than, and further Preferably 1×10 18 atoms / cm 3 less than. By using a metal oxide with sufficiently reduced impurities such as hydrogen in the channel formation region of the transistor, stable electrical characteristics can be imparted.

[0142] Also, when a metal oxide is used for the oxide 530, the carrier concentration of the metal oxide in the channel formation region is preferably 1×10 cm 18 cm -3 or less, more preferably less than 1×10 17 cm -3 un satisfied, even more preferably less than 1×10 16 cm -3 less than, even more preferably 1×10 13 cm -3 less than, even more preferably less than 1×10 12 cm -3 less than is even more preferable. Note that the lower limit value of the carrier concentration of the metal oxide in the channel formation region is not particularly limited, but for example, it can be 1×10 cm -9 cm -3 and.

[0143] Also, when a metal oxide is used for the oxide 530, when the conductor 542 (conductor 542a and conductor 542b) is in contact with the oxide 530, oxygen in the oxide 530 may diffuse into the conductor 54 2 and the conductor 542 may be oxidized. When the conductor 542 is oxidized, the probability that the conductivity of the conductor 542 decreases is high. Note that the diffusion of oxygen in the oxide 530 into the conductor 542 can be rephrased as the conductor 542 absorbing oxygen in the oxide 530. can.

[0144] Also, oxygen in the oxide 530 is the conductor 542 (conductor 542a and conductor 542b) Diffusion into the oxide 530b between the conductor 542a and the oxide 530b and between the conductor 542b and the oxide 530b. A foreign layer may be formed between the conductive material 542 and the object 530b. The foreign layer may have more oxygen than the conductive material 542. Since the layer contains a large amount of conductor 542, the layer is presumed to have insulating properties. The three-layer structure of the hetero layer and the oxide 530b is a three-layer structure consisting of a metal, an insulator, and a semiconductor. It can be regarded as MIS (Metal-Insulator-Semiconductor) or) structure, or a diode junction structure mainly based on the MIS structure.

[0145] The different layer is not limited to being formed between the conductor 542 and the oxide 530b. For example, a heterogeneous layer may be formed between the conductor 542 and the oxide 530c. between the conductor 542 and the oxide 530b, and between the conductor 542 and the oxide 530c. It may be formed.

[0146] In addition, the metal oxide that functions as a channel formation region in the oxide 530 is a band gap metal oxide. It is preferable to use a gap 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 can be reduced.

[0147] The oxide 530 has an oxide 530a under the oxide 530b. The structure formed below the oxide 530b is prevented from diffusing impurities into the oxide 530b. In addition, by having the oxide 530c on the oxide 530b, the oxide 530 The structure formed above the oxide 530c is prevented from diffusing impurities into the oxide 530b. It is possible.

[0148] The oxide 530 preferably has a laminated structure of a plurality of oxide layers with different atomic ratios of each metal atom. Specifically, in the metal oxide used for the oxide 530a, the atomic ratio of the element M in the constituent elements is preferably larger than the atomic ratio of the element M in the constituent elements in the metal oxide used for the oxide 530b. Also, in the metal oxide used for the oxide 530a, the atomic ratio of the element M to In is preferably larger than the atomic ratio of the element M to In in the metal oxide used for the oxide 530b. Further, in the metal oxide used for the oxide 530b, the atomic ratio of In to the element M is preferably larger than the atomic ratio of In to the element M in the metal oxide used for the oxide 530a. Also, the oxide 530c can use a metal oxide that can be used for the oxide 530a or the oxide 530b.

[0149] Specifically, as the oxide 530a, a metal oxide with In:Ga:Zn = 1:3:4 [atomic ratio] or 1:1:0.5 [atomic ratio] may be used. Also, as the oxide 530b, a metal oxide with In:Ga:Zn = 4:2:3 [atomic ratio] or 1:1:1 [atomic ratio] may be used. Also, as the oxide 530c, a metal oxide with In:Ga:Zn = 1:3:4 [atomic ratio], Ga:Zn = 2:1 [atomic ratio], or Ga:Zn = 2:5 [atomic ratio] may be used. Further, specific examples of the case where the oxide 530c has a laminated structure include a laminated structure of In:Ga:Zn = 4:2:3 [atomic ratio] and In:Ga:Zn = 1:3:4 [atomic ratio], a laminated structure of Ga:Zn = 2:1 [atomic ratio] and In:Ga:Zn = 4 ​​​​​​​​​​​​​​​:2:3 [atomic ratio] and the laminated structure, Ga:Zn = 2:5 [atomic ratio], and In:Ga: Zn = 4:2:3 [atomic ratio] and the laminated structure, gallium oxide, and In:Ga: 2:3 [atomic ratio] and the laminated structure and the like can be mentioned.

[0150] In addition, it is preferable that the energy of the lower end of the conduction band of the oxide 530a and the oxide 530c is higher than the energy of the lower end of the conduction band of the oxide 530 b. In other words, it is preferable that the electron affinities of the oxide 530a and the oxide 530c are smaller than the electron affinity of the oxide 530b.

[0151] Here, at the junction of the oxide 530a, the oxide 530b, and the oxide 530c, the energy level of the lower end of the conduction band changes smoothly. In other words, the energy level of the lower end of the conduction band at the junction of the oxide 530a, the oxide 530b, and the oxide 530c can be said to change continuously or to be continuously joined. To achieve this, it is advisable to lower the density of defect levels in the mixed layer formed at the interface between the oxide 530a and the oxide 530b and at the interface between the oxide 530b and the oxide 530c. Specifically, by having a common element (as the main component) other than oxygen between the oxide 530a and the oxide 530b and between the oxide 530b and the oxide 530c, a mixed layer with a low density of defect levels can be formed. For example, when the oxide 530b is an In-Ga-Zn oxide, as the oxide 530a and the oxide 530c, an In-Ga-Zn oxide, a Ga-Zn oxide, gallium oxide, etc. may be used.

[0152] Specifically, when the oxide 530a and the oxide 530b, and the oxide 530b and the oxide 530c have a common element (as the main component) other than oxygen, a mixed layer with a low density of defect levels can be formed. For example, when the oxide 530b is an In-Ga-Zn oxide, as the oxide 530a and the oxide 530c, an In-Ga-Zn oxide, a Ga-Zn oxide, gallium oxide, etc. may be used.

[0153] ​​​At this time, the main path of the carriers is the oxide 530b. By configuring the object 530c as described above, the interface between the oxide 530a and the oxide 530b, and The defect state density at the interface between the oxide 530b and the oxide 530c can be reduced. Therefore, the effect of interface scattering on carrier conduction is reduced, and the transistor 12 has high A high on-current can be obtained.

[0154] The semiconductor material that can be used for the oxide 530 is not limited to the above-mentioned metal oxides. The oxide 530 is a semiconductor material having a band gap (a zero-gap semiconductor). For example, semiconductors of single elements such as silicon, gallium arsenide, Compound semiconductors such as ZnO, layered materials that function as semiconductors (atomic layer materials, 2D materials, etc.) It is preferable to use, for example, a semiconductor material. It is preferable to use such a material as the semiconductor material.

[0155] In this specification, the term "layered material" refers to a group of materials having a layered crystal structure. The layered crystal structure is formed by covalent and ionic bonds, and the layers are The structure is made up of layers of molecules that are weaker than covalent or ionic bonds, such as those formed by the force of a sulphur atom. Layered materials have high electrical conductivity within a unit layer, that is, high two-dimensional electrical conductivity. A material that functions as a semiconductor and has high two-dimensional electrical conductivity is used for the channel formation region. This makes it possible to provide a transistor with a large on-state current.

[0156] Layered materials include graphene, silicene, and chalcogenides. is a compound containing a chalcogen. The chalcogen is a general term for elements belonging to Group 16 and includes oxygen, sulfur, selenium, tellurium, polonium, and livermorium. Also, as chalcogenides, transition metal chalcogenides, Group 13 chalcogenides, etc. can be mentioned .

[0157] As the oxide 530, for example, it is preferable to use a transition metal chalcogenide that functions as a semiconductor . Specific examples of transition metal chalcogenides applicable as the oxide 530 include molybdenum sulfide (typically MoS2), molybdenum selenide (typically MoSe 2), molybdenum telluride (typically MoTe2), tungsten sulfide (typically W S2), tungsten selenide (typically WSe2), tungsten telluride (typically WTe2), hafnium sulfide (typically HfS2), hafnium selenide (typically HfSe2), zirconium sulfide (typically ZrS2), zirconium selenide (typically ZrSe2), etc.

[0158] On the oxide 530b, a conductor 542a that functions as a source electrode and a drain electrode , and a conductor 542b are provided. As the conductor 542a and the conductor 542b, aluminum , chromium, copper, silver, gold, platinum, tantalum, nickel, titanium, molybdenum, tungsten , hafnium, vanadium, niobium, manganese, magnesium, zirconium , beryllium, indium, ruthenium, iridium, strontium, lanthanum are selected from the selected metal elements, or an alloy containing the above-mentioned metal elements as components, or an alloy formed by combining the above-mentioned metal elements is preferably used. For example, tantalum nitride, titanium nitride, tungsten Nitrides containing titanium and aluminum, nitrides containing tantalum and aluminum, ruthenium oxide , ruthenium nitride, oxides containing strontium and ruthenium, oxides containing lanthanum and nickel etc. are preferably used. Also, tantalum nitride, titanium nitride, nitrides containing titanium and aluminum, nitrides containing tantalum and aluminum, ruthenium oxide, ruthenium nitride, oxides containing strontium and ruthenium, oxides containing lanthanum and nickel are preferably used because they are conductive materials that are difficult to oxidize or materials that maintain conductivity even when absorbing oxygen. Furthermore, metal nitride films such as tantalum nitride are preferable because they have a barrier property against hydrogen or oxygen.

[0159] Also, in Fig. 17, the conductors 542a and 542b are shown as single-layer structures, but they may also have a laminated structure of two or more layers. For example, a laminated structure of a tantalum nitride film and a tungsten film is acceptable. Also, a titanium film and an aluminum film may be laminated. Also, a two-layer structure in which an aluminum film is 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 are also acceptable. Also, a three-layer structure in which a titanium film or a titanium nitride film and an aluminum film or a copper film are laminated on the titanium film or the titanium nitride film, and then a titanium film or a titanium nitride film is formed thereon, a three-layer structure in which a molybdenum film or a molybdenum nitride film and an aluminum film or a copper film are laminated on the molybdenum film or the molybdenum nitride film, and then a molybdenum film or a molybdenum nitride film is formed thereon, etc. exist. Note that transparent materials containing indium oxide, tin oxide, or zinc oxide

[0160] Also, a three-layer structure in which a titanium film or a titanium nitride film and an aluminum film or a copper film are laminated on the titanium film or the titanium nitride film, and then a titanium film or a titanium nitride film is formed thereon, a three-layer structure in which a molybdenum film or a molybdenum nitride film and an aluminum film or a copper film are laminated on the molybdenum film or the molybdenum nitride film, and then a molybdenum film or a molybdenum nitride film is formed thereon, etc. exist. Note that transparent materials containing indium oxide, tin oxide, or zinc oxide Also, a three-layer structure in which a molybdenum film or a molybdenum nitride film and an aluminum film or a copper film are laminated on the molybdenum film or the molybdenum nitride film, and then a molybdenum film or a molybdenum nitride film is formed thereon, etc. exist. In addition, transparent materials containing indium oxide, tin oxide, or zinc oxide are provided. Transparent conductive materials may also be used.

[0161] As shown in FIG. 17A, the conductor 542a (conductor 542b) of the oxide 530 At the interface and in the vicinity thereof, a region 543a and a region 543b are formed as low resistance regions. 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 formation region is formed in the region between a and region 543b.

[0162] By providing the conductor 542a (conductor 542b) so as to be in contact with the oxide 530, The oxygen concentration in the region 543a (region 543b) may decrease. The metal contained in the conductor 542a (conductor 542b) and the oxide 530 are In such a case, a metal compound layer containing the component may be formed in the region 543a (region The carrier concentration in the region 543a (region 543b) increases, and the region 543a (region 543b) becomes a low resistance region. become.

[0163] The insulator 544 is provided to cover the conductor 542a and the conductor 542b. At this time, the insulator 544 prevents the oxidation of the oxide 542a and the conductor 542b. 30 and may be provided in contact with the insulator 524 .

[0164] Insulator 544: hafnium, aluminum, gallium, yttrium, zirconium tungsten, titanium, tantalum, nickel, germanium, neodymium, lanthanum It is possible to use a metal oxide containing one or more metals selected from the group consisting of magnesium, etc. Silicon oxynitride or silicon nitride may also be used as the insulator 544. can be done.

[0165] In particular, the insulator 544 may be made of oxide of either or both of aluminum and hafnium. Aluminum oxide, hafnium oxide, or aluminum and hafnium oxide are insulators containing It is preferable to use oxides containing hafnium (hafnium aluminate). Hafnium aluminate has higher heat resistance than hafnium oxide film. Therefore, it is suitable for heat treatment in the later process. In theory, this is preferable because it is difficult to crystallize. If the material is oxidation-resistant or the conductivity does not decrease significantly even when oxygen is absorbed, the insulator 544 is not an essential component and may be appropriately designed depending on the desired transistor characteristics.

[0166] By including the insulator 544, impurities such as water and hydrogen contained in the insulator 580 are prevented from being converted into oxygen. The diffusion of the oxide 530b through the oxide 530c and the insulator 550 can be suppressed. In addition, the conductor 560 can be prevented from being oxidized due to excess oxygen contained in the insulator 580. It can be controlled.

[0167] The insulator 550 functions as a first gate insulating film. It is preferable that the insulator 550 is disposed so as to contact the inside (top and side surfaces) of the insulator 550. Similar to the insulator 524 described above, this insulator contains excess oxygen and releases oxygen when heated. It is preferable to form the insulating layer using an insulating material.

[0168] Specifically, silicon oxide having excess oxygen, silicon oxynitride, silicon nitride oxide, Silicon nitride, silicon oxide with fluorine added, silicon oxide with carbon added, carbon, and silicon oxide with nitrogen added, and silicon oxide having pores can be used. In particular, , silicon oxide and silicon oxynitride are preferable because they are stable against heat.

[0169] An insulator that releases oxygen by heating is provided in contact with the upper surface of the oxide 530c as the insulator 550, so that oxygen can be effectively supplied from the insulator 550 to the channel formation region of the oxide 530b through the oxide 530c. Also, similar to the insulator 524, it is preferable that the concentration of impurities such as water or hydrogen in the insulator 550 is reduced. The film thickness of the insulator 5 50 is preferably 1 nm or more and 20 nm or less.

[0170] In addition, in order to efficiently supply the excess oxygen possessed by the insulator 550 to the oxide 530, a metal oxide may be provided between the insulator 550 and the conductor 560. The metal oxide preferably has a function of suppressing the diffusion of oxygen from the insulator 550 to the conductor 560. By providing a metal oxide having a function of suppressing the diffusion of oxygen, the diffusion of excess oxygen from the insulator 550 to the conductor 560 is suppressed. That is, a decrease in the amount of excess oxygen supplied to the oxide 530 can be suppressed. In addition, oxidation of the conductor 560 by excess oxygen can be suppressed. As the metal oxide, a material that can be used for the insulator 544 may be used.

[0171] Note that the insulator 550 may have a laminated structure, similar to the second gate insulating film. As the miniaturization and high integration of transistors progress, problems such as leakage current may occur due to the thinning of the gate insulating film. Therefore, an insulator that functions as a gate insulating film is made into a high- ​​​ By adopting a laminated structure of k material and a thermally stable material, while maintaining the physical film thickness, it becomes possible to reduce the gate potential during transistor operation. Also, a laminated structure that is thermally stable and has a high relative dielectric constant can be achieved.

[0172] The conductor 560 that functions as the first gate electrode is shown as a two-layer structure in FIGS. 17A and 17B, but it may also have a single-layer structure or a laminated structure of three or more layers.

[0173] The conductor 560a is a conductive material having a function of suppressing the diffusion of impurities such as hydrogen atoms, hydrogen molecules, water molecules, nitrogen atoms, nitrogen molecules, nitrogen oxide molecules (N2O, NO, NO2, etc.), and copper atoms. Alternatively, it is preferable to use a conductive material having a function of suppressing the diffusion of oxygen (for example, at least one of oxygen atoms, oxygen molecules, etc.). Since the conductor 560a has a function of suppressing the diffusion of oxygen, it is possible to suppress the oxidation of the conductor 5 60b by the oxygen contained in the insulator 550 and the decrease in conductivity. As the conductive material having a function of suppressing the diffusion of oxygen, for example, tantalum, tantalum nitride, ruthenium, or ruthenium oxide, etc. are preferably used. Also, as the conductor 560a, an oxide semiconductor applicable to the oxide 530 can be used. In that case, by forming the conductor 560b by sputtering ring method, the electrical resistance value of the conductor 560a can be reduced to make it a conductor. This can be called an OC (Oxide Conductor) electrode. Also, the conductor 560b is a conductive material mainly composed of tungsten, copper, or aluminum. When the conductor 560b is formed by the sputtering ring method, the electrical resistance value of the conductor 560a can be reduced to make it a conductor. This can be called an OC (Oxide Conductor) electrode.

[0174] Also, the conductor 560b is a conductive material mainly composed of tungsten, copper, or aluminum. It is preferable to use the material. Further, since the conductor 560b also functions as wiring, it is preferable to use a conductor with high conductivity. For example, a conductive material mainly composed of tungsten, copper, or aluminum can be used. Further, the conductor 560b may have a laminated structure. For example, it may have a laminated structure of titanium or titanium nitride and the above conductive material. It is preferable to use a conductor with high conductivity. For example, a conductive material mainly composed of tungsten, copper, or aluminum can be used. Further, the conductor 560b may have a laminated structure. For example, it may have a laminated structure of titanium or titanium nitride and the above conductive material. It is preferable that the insulator 580 has an oxygen-rich region. For example, as the insulator 580, silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, silicon oxide added with fluorine, silicon oxide added with carbon, carbon, and silicon oxide added with nitrogen, silicon oxide having pores, or resin, etc. are preferably used. In particular, silicon oxide and silicon oxynitride are preferable because they are thermally stable. In particular, silicon oxide and silicon oxide having pores are preferable because an oxygen-rich region can be easily formed in a later process.

[0175] The insulator 580 is provided on the conductors 542a and 542b via the insulator 544. It is preferable that the insulator 580 has an oxygen-rich region. For example, as the insulator 580, silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, silicon oxide added with fluorine, silicon oxide added with carbon, carbon, and silicon oxide added with nitrogen, silicon oxide having pores, or resin, etc. are preferably used. In particular, silicon oxide and silicon oxynitride are preferable because they are thermally stable. In particular, silicon oxide and silicon oxide having pores are preferable because an oxygen-rich region can be easily formed in a later process. It is preferable that the insulator 580 has an oxygen-rich region. For example, as the insulator 580, silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, silicon oxide added with fluorine, silicon oxide added with carbon, carbon, and silicon oxide added with nitrogen, silicon oxide having pores, or resin, etc. are preferably used. In particular, silicon oxide and silicon oxynitride are preferable because they are thermally stable. In particular, silicon oxide and silicon oxide having pores are preferable because an oxygen-rich region can be easily formed in a later process. It is preferable that the insulator 580 has an oxygen-rich region. For example, as the insulator 580, silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, silicon oxide added with fluorine, silicon oxide added with carbon, carbon, and silicon oxide added with nitrogen, silicon oxide having pores, or resin, etc. are preferably used. In particular, silicon oxide and silicon oxynitride are preferable because they are thermally stable. In particular, silicon oxide and silicon oxide having pores are preferable because an oxygen-rich region can be easily formed in a later process. It is preferable that the insulator 580 has an oxygen-rich region. For example, as the insulator 580, silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, silicon oxide added with fluorine, silicon oxide added with carbon, carbon, and silicon oxide added with nitrogen, silicon oxide having pores, or resin, etc. are preferably used. In particular, silicon oxide and silicon oxynitride are preferable because they are thermally stable. In particular, silicon oxide and silicon oxide having pores are preferable because an oxygen-rich region can be easily formed in a later process. It is preferable that the insulator 580 has an oxygen-rich region. For example, as the insulator 580, silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, silicon oxide added with fluorine, silicon oxide added with carbon, carbon, and silicon oxide added with nitrogen, silicon oxide having pores, or resin, etc. are preferably used. In particular, silicon oxide and silicon oxynitride are preferable because they are thermally stable. In particular, silicon oxide and silicon oxide having pores are preferable because an oxygen-rich region can be easily formed in a later process. It is preferable that the insulator 580 has an oxygen-rich region. For example, as the insulator 580, silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, silicon oxide added with fluorine, silicon oxide added with carbon, carbon, and silicon oxide added with nitrogen, silicon oxide having pores, or resin, etc. are preferably used. In particular, silicon oxide and silicon oxynitride are preferable because they are thermally stable. In particular, silicon oxide and silicon oxide having pores are preferable because an oxygen-rich region can be easily formed in a later process. It is preferable that the insulator 580 has an oxygen-rich region. For example, as the insulator 580, silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, silicon oxide added with fluorine, silicon oxide added with carbon, carbon, and silicon oxide added with nitrogen, silicon oxide having pores, or resin, etc. are preferably used. In particular, silicon oxide and silicon oxynitride are preferable because they are thermally stable. In particular, silicon oxide and silicon oxide having pores are preferable because an oxygen-rich region can be easily formed in a later process.

[0176] It is preferable that the insulator 580 has an oxygen-rich region. By providing the insulator 580 that releases oxygen upon heating so as to have a region in contact with the oxide 530c, the oxygen in the insulator 580 can be efficiently supplied to the oxides 530a and 530b through the oxide 530c. It is preferable that the concentration of impurities such as water or hydrogen in the insulator 580 is reduced. It is preferable that the insulator 580 has an oxygen-rich region. By providing the insulator 580 that releases oxygen upon heating so as to have a region in contact with the oxide 530c, the oxygen in the insulator 580 can be efficiently supplied to the oxides 530a and 530b through the oxide 530c. It is preferable that the concentration of impurities such as water or hydrogen in the insulator 580 is reduced. It is preferable that the insulator 580 has an oxygen-rich region. By providing the insulator 580 that releases oxygen upon heating so as to have a region in contact with the oxide 530c, the oxygen in the insulator 580 can be efficiently supplied to the oxides 530a and 530b through the oxide 530c. It is preferable that the concentration of impurities such as water or hydrogen in the insulator 580 is reduced. It is preferable that the insulator 580 has an oxygen-rich region. By providing the insulator 580 that releases oxygen upon heating so as to have a region in contact with the oxide 530c, the oxygen in the insulator 580 can be efficiently supplied to the oxides 530a and 530b through the oxide 530c. It is preferable that the concentration of impurities such as water or hydrogen in the insulator 580 is reduced. It is preferable that the insulator 580 has an oxygen-rich region. By providing the insulator 580 that releases oxygen upon heating so as to have a region in contact with the oxide 530c, the oxygen in the insulator 580 can be efficiently supplied to the oxides 530a and 530b through the oxide 530c. It is preferable that the concentration of impurities such as water or hydrogen in the insulator 580 is reduced.

[0177] The opening of the insulator 580 is formed to overlap the region between the conductors 542a and 542b. ​As a result, the conductor 560 is formed so as to be embedded in the opening of the insulator 580 and the region sandwiched between the conductor 542a and the conductor 542b.

[0178] When miniaturizing a semiconductor device, it is required to shorten the gate length, but it is necessary to prevent the conductivity of the conductor 5 60 from decreasing. Therefore, if the film thickness of the conductor 560 is increased, the conductor 560 may have a high aspect ratio. In the present embodiment, since the conductor 560 is provided so as to be embedded in the opening of the insulator 580, even if the conductor 560 has a high aspect ratio, the conductor 560 can be formed without collapsing during the process.

[0179] The insulator 574 is preferably provided in contact with the upper surface of the insulator 580, the upper surface of the conductor 560, and the upper surface of the insulator 550. By forming the insulator 574 by sputtering, an excess oxygen region can be provided in the insulator 550 and the insulator 580. Thereby, oxygen can be supplied from the excess oxygen region into the oxide 530.

[0180] For example, as the insulator 574, a metal oxide containing one or more selected from hafnium, aluminum, gallium, yttrium, zirconium, tungsten, titanium, tantalum, nickel, germanium, or magnesium etc. can be used.

[0181] In particular, aluminum oxide has high barrier properties, and even if it is a thin film of 0.5 nm or more and 3.0 nm or less, it can suppress the diffusion of hydrogen and nitrogen. Therefore, aluminum oxide formed by sputtering is both an oxygen supply source and a barrier film for impurities such as hydrogen. It can also have a function as...

[0182] Further, it is preferable to provide an insulator 581 that functions as an interlayer film on the insulator 574. Similar to the insulator 524 and the like, the insulator 581 preferably has a reduced concentration of impurities such as water or hydrogen in the film.

[0183] In addition, conductors 540a and 540b are disposed at openings formed in the insulator 581, the insulator 574, the insulator 580, and the insulator 544. The conductors 540a and 540b are provided to face each other with the conductor 560 interposed therebetween. The conductors 540a and 540b have the same configuration as the conductors 546 and 548 described later.

[0184] An insulator 582 is provided on the insulator 581. It is preferable to use a material that is barrier - resistant to oxygen and hydrogen for the insulator 582. Therefore, the same material as the insulator 514 can be used for the insulator 582. For example, it is preferable to use metal oxides such as aluminum oxide, hafnium oxide, and tantalum oxide for the insulator 582. In particular, aluminum oxide has a high blocking effect of not allowing the film to permeate both oxygen and impurities such as hydrogen and moisture, which are factors causing fluctuations in the electrical characteristics of transistors. Therefore, aluminum oxide can prevent the entry of impurities such as hydrogen and moisture into the transistor 12 during and after the manufacturing process of the transistor. In addition, it can suppress the release of oxygen from the oxides constituting the transistor 12. Therefore, it is suitable for use as a protective film for the transistor 12.

[0185]

[0186] ​​​​​​​​​​​​Also, an insulator 586 is provided on the insulator 582. The insulator 586 can use the same material as the insulator 320. Further, by applying a material with a relatively low dielectric constant to these insulators, the parasitic capacitance generated between the wirings can be reduced. For example, as the insulator 586, a silicon oxide film, a silicon oxynitride film, or the like can be used.

[0187] Also, conductors 546 and conductors such as 548 are embedded in the insulators 520, 522, 524, 544, 580, 574, 581, 582, and 586.

[0188] The conductors 546 and 548 have functions as plugs connected to the capacitor 14, the transistor 12, or the transistor 13, or as wirings. The conductors 546 and 548 can be provided using the same material as the conductor 328 or the conductor 330.

[0189] After the formation of the transistor 12, an opening may be formed so as to surround the transistor 12, and an insulator having high barrier properties against hydrogen or water may be formed so as to cover the opening. By wrapping the transistor 12 with the above-mentioned insulator having high barrier properties, it is possible to prevent moisture and hydrogen from entering from the outside. Alternatively, a plurality of transistors 12 may be collectively wrapped with an insulator having high barrier properties against hydrogen or water. When forming an opening so as to surround the transistor 12, for example, an opening reaching the insulator 514 or the insulator 522 is formed, and the above-mentioned insulator having high barrier properties is formed so as to be in contact with the insulator 514 or the insulator 522. ​​​​​​​​​​​​When formed, it is suitable because it can also serve as part of the manufacturing process of the transistor 12. Note that water As the element or insulator with high barrier property to water, for example, the same material as the insulator 522 can be used.

[0190] Subsequently, a capacitor 14 is provided above the transistor 12. The capacitor 14 has a conductor 610, a conductor 620, and an insulator 630.

[0191] Also, a conductor 612 may be provided on the conductor 546 and the conductor 548. The conductor 6 12 has a function as a plug connected to the transistor 12 or a wiring. The conductor 6 10 has a function as an electrode of the capacitor 14. Note that the conductor 612 and the conductor 610 can be formed simultaneously.

[0192] For the conductor 612 and the conductor 610, a metal film containing an element selected from molybdenum, titanium, tantalum, tungsten , aluminum, copper, chromium, neodymium, scandium, or a metal nitride film (tantalum nitride film, titanium nitride film, molybdenum nitride film, tungsten nitride film) having the above-mentioned elements as components can be used. Or, indium tin oxide, indium oxide containing tungsten oxide, indium zinc oxide containing tungsten oxide oxide, indium oxide containing titanium oxide, indium tin oxide containing titanium oxide, indium zinc oxide, conductive materials such as indium tin oxide added with silicon oxide can also be applied. That's all right.

[0193] In FIG. 15, the conductor 612 and the conductor 610 are shown in a single-layer structure, but it is not limited to this configuration and a laminated structure of two or more layers may also be used. For example, a conductor with barrier property and a conductor with high conductivity A conductor having a barrier property and a conductor having high adhesiveness to a highly conductive conductor may be formed between the conductors.

[0194] The conductor 620 is provided so as to overlap with the conductor 610 via the insulator 630. Note that the conductor 620 can be formed of a conductive material such as a metal material, an alloy material, or a metal oxide material. It is preferable to use a high melting point material such as tungsten or molybdenum that achieves both heat resistance and conductivity, and it is particularly preferable to use tungsten. Also, when forming simultaneously with other structures such as conductors, Cu (copper), Al (aluminum), or the like, which are low resistance metal materials, may be used.

[0195] An insulator 640 is provided on the conductor 620 and the insulator 630. The insulator 64 0 can be formed using the same material as the insulator 320. Also, the insulator 640 may function as a planarization film that covers the uneven shape below it.

[0196] By using this structure, miniaturization or high integration can be achieved in a semiconductor device using a transistor having an oxide semiconductor.

[0197] FIGS. 18A and 18B are modified examples of the transistor 12 shown in FIGS. 17A and 17B. FIG. 17A is a cross-sectional view of the transistor 12 in the channel length direction, and FIG. 17B is a cross-sectional view of the transistor 12 in the channel width direction. Note that the configurations shown in FIGS. 18A and 18B can also be applied to other transistors included in a semiconductor device according to an aspect of the present invention, such as the transistor 13.

[0198] ​​​​​​​​​FIG. 18A is a cross-sectional view of the transistor 12 in the channel length direction, and FIG. 18A and 18B are cross-sectional views of the transistor 12 in the channel width direction. 2 has an insulator 402 and an insulator 404, which is different from the transistor shown in FIG. 17A and FIG. 17B. The conductor 540a is different from the conductor 12 in that an insulator 552 is provided in contact with the side surface of the conductor 540a. The point where the insulator 552 is provided in contact with the side surface of the body 540b is the same as that shown in FIGS. 17A and 17B. 17A and 17B, the transistor 12 does not have an insulator 520. 1. This differs from transistor 12 shown.

[0199] The transistor 12 shown in FIGS. 18A and 18B has an insulator 402 provided on an insulator 512. Furthermore, an insulator 404 is provided over the insulator 574 and over the insulator 402.

[0200] In the transistor 12 shown in FIGS. 18A and 18B, the insulators 514, 516, and The insulator 522, the insulator 524, the insulator 544, the insulator 580, and the insulator 574 are patterned. The insulator 404 covers the electrodes. , the top surface of the insulator 574, the side surface of the insulator 574, the side surface of the insulator 580, and the side surface of the insulator 544 , a side of the insulator 524, a side of the insulator 522, a side of the insulator 516, and a side of the insulator 514 , and the top surface of the insulator 402. As a result, the oxide 530 and the like are in contact with the top surface of the insulator 404. and is isolated from the outside by an insulator 402.

[0201] The insulators 402 and 404 are made of at least hydrogen (e.g., hydrogen atoms, hydrogen molecules, etc.). For example, the insulator 402 and the insulator 403 each preferably have a high function of suppressing the diffusion of water molecules. As the insulator 404, silicon nitride or silicon oxynitride, which is a material with high hydrogen barrier properties, is preferably used. This can suppress the diffusion of hydrogen or the like into the oxide 530, so that the characteristics of the transistor 12 can be prevented from deteriorating. Therefore, the reliability of the semiconductor device according to one aspect of the present invention can be enhanced. The insulator 552 is provided in contact with the insulator 581, the insulator 404, the insulator 574, the insulator 580, and the insulator 544. The insulator 552 preferably has a function of suppressing the diffusion of hydrogen or water molecules. For example, as the insulator 552, an insulator such as silicon nitride, aluminum oxide, or silicon oxynitride, which is a material with high hydrogen barrier properties, is preferably used. In particular, since silicon nitride is a material with high hydrogen barrier properties, it is suitable to be used as the insulator 552. By using a material with high hydrogen barrier properties as the insulator 552, the diffusion of impurities such as water or hydrogen from the insulator 580 or the like through the conductor 540a and the conductor 540b into the oxide 530 can be suppressed. Also, the absorption of oxygen contained in the insulator 580 by the conductor 540a and the conductor 540b can be suppressed. As described above, the reliability of the semiconductor device according to one aspect of the present invention can be enhanced. Figure 19 is a cross-sectional view showing a configuration example of a semiconductor device when the transistors 12 and 13 are configured as shown in FIGS. 18A and 18B. An insulator 552 is provided on the side surface of the conductor 546.

[0202] This embodiment can be implemented in appropriate combination with the configurations described in other embodiments and the like.

[0203]

[0204]

[0203]

[0204]

[0204]

[0205] (Embodiment 3) In this embodiment, the configurations of CAC-OS and CAAC-OS, which are metal oxides that can be used for the OS transistor described in the above embodiment, will be described. Note that in this specification and the like, CAC represents an example of the function or the composition of the material, and CAAC represents an example of the crystal structure. in this specification and the like, CAC represents an example of the function or the composition of the material, and CAAC represents an example of the crystal structure.

[0206] <Configuration of Metal Oxide> CAC-OS or CAC-metal oxide has a conductive function in a part of the material and an insulating function in a part of the material, and has a function as a semiconductor in the whole material. When CAC-OS or CAC-metal oxide is used for the active layer of a transistor, the conductive function is the function of flowing electrons (or holes) serving as carriers, and the insulating function is the function of not flowing electrons serving as carriers. By causing the conductive function and the insulating function to act complementarily with each other, a switching function (On / Off function) can be imparted to CAC-OS or CAC-metal oxide. In CAC-OS or CAC-metal oxide, by separating each function, both functions can be enhanced to the maximum extent.

[0207] In addition, CAC-OS or CAC-metal oxide has a conductive region and an insulating region. The conductive region has the above-described conductive function, and the insulating region has the above-described insulating function. Also, in the material, the conductive region and the insulating region may be separated at the nanoparticle level. Also, the conductive region and the insulating region are each in the material There may be a case of being offset. Also, the conductive region may be observed with its periphery blurred and connected in a cloud shape. There may be a case.

[0208] Also, in CAC-OS or CAC-metal oxide, the conductive region and the insulative region may be dispersed in the material with sizes of 0.5 nm or more and 10 nm or less, preferably 0.5 nm or more and 3 nm or less, respectively. Also, in CAC-OS or CAC-metal oxide, the conductive region and the insulative region may be dispersed in the material with sizes of 0.5 nm or more and 10 nm or less, preferably 0.5 nm or more and 3 nm or less, respectively. There may be a case where they are dispersed in the material with sizes of 0.5 nm or more and 10 nm or less, preferably 0.5 nm or more and 3 nm or less.

[0209] Also, CAC-OS or CAC-metal oxide is composed of components having different band gaps. For example, CAC-OS or CAC-metal oxide is composed of a component having a wide band gap due to the insulative region and a component having a narrow band gap due to the conductive region. In such a configuration, when carriers flow, carriers mainly flow in the component having the narrow band gap. Also, the component having the narrow band gap acts complementarily to the component having the wide band gap, and carriers also flow in the component having the wide band gap in conjunction with the component having the narrow band gap. Therefore, when the above CAC-OS or CAC-metal oxide is used in the channel formation region of a transistor, a high current driving force, that is, a large on-current, and a high field-effect mobility can be obtained in the on state of the transistor. Also, CAC-OS or CAC-metal oxide is composed of components having different band gaps. For example, CAC-OS or CAC-metal oxide is composed of a component having a wide band gap due to the insulative region and a component having a narrow band gap due to the conductive region. In such a configuration, when carriers flow, carriers mainly flow in the component having the narrow band gap. Also, the component having the narrow band gap acts complementarily to the component having the wide band gap, and carriers also flow in the component having the wide band gap in conjunction with the component having the narrow band gap. Therefore, when the above CAC-OS or CAC-metal oxide is used in the channel formation region of a transistor, a high current driving force, that is, a large on-current, and a high field-effect mobility can be obtained in the on state of the transistor. e is composed of a component having a wide band gap due to the insulative region and a component having a narrow band gap due to the conductive region. In this case, when carriers flow, carriers mainly flow in the component having the narrow band gap. Also, the component having the narrow band gap acts complementarily to the component having the wide band gap, and carriers also flow in the component having the wide band gap in conjunction with the component having the narrow band gap. Therefore, when the above CAC-OS or CAC-metal oxide is used in the channel formation region of a transistor, a high current driving force, that is, a large on-current, and a high field-effect mobility can be obtained in the on state of the transistor. In this case, when carriers flow, carriers mainly flow in the component having the narrow band gap. Also, the component having the narrow band gap acts complementarily to the component having the wide band gap, and carriers also flow in the component having the wide band gap in conjunction with the component having the narrow band gap. Therefore, when the above CAC-OS or CAC-metal oxide is used in the channel formation region of a transistor, a high current driving force, that is, a large on-current, and a high field-effect mobility can be obtained in the on state of the transistor. The component having the narrow band gap acts complementarily to the component having the wide band gap, and carriers also flow in the component having the wide band gap in conjunction with the component having the narrow band gap. For this reason, when the above CAC-OS or CAC-metal oxide is used in the channel formation region of a transistor, a high current driving force, that is, a large on-current, and a high field-effect mobility can be obtained in the on state of the transistor. In other words, CAC-OS or CAC-metal oxide can also be referred to as a matrix composite or a metal matrix composite. In other words, CAC-OS or CAC-metal oxide can also be referred to as a matrix composite or a metal matrix composite. In other words, CAC-OS or CAC-metal oxide can also be referred to as a matrix composite or a metal matrix composite.

[0210] In other words, CAC-OS or CAC-metal oxide can also be referred to as a matrix composite or a metal matrix composite. (matrix composite), or a metal matrix composite (metal m atrix composite).

[0211] <Structure of Metal Oxide> Oxide semiconductors are classified into single-crystalline oxide semiconductors and other non-single-crystalline oxide semiconductors. Examples of non-single-crystalline oxide semiconductors include CAAC-OS, polycrystalline oxide semiconductors , nc-OS (nanocrystalline oxide semiconduct or), pseudo-amorphous oxide semiconductors (a-like OS: amorphous-like oxide semiconductor), and amorphous oxide semiconductors.

[0212] CAAC-OS has a c-axis orientation and a crystal structure in which a plurality of nanocrystals are connected in the a-b plane direction and have strain. Note that the strain refers to a location where the lattice arrangement changes between a region with an aligned lattice arrangement and another region with an aligned lattice arrangement in the region where the plurality of nanocrystals are connected.

[0213] Nanocrystals are based on hexagons, but are not necessarily regular hexagons and may be non-regular hexagons. Also, in the strain, there may be cases where the lattice arrangement has pentagons, heptagons, etc. In addition, in CAAC-OS, it is not possible to confirm a clear grain boundary (also called a grain boundary) even in the vicinity of the strain. That is, it can be seen that the formation of grain boundaries is suppressed by the strain of the lattice arrangement. This is considered to be because CAAC-OS can tolerate strain due to the fact that the arrangement of oxygen atoms is not dense in the a-b plane direction and the interatomic bond distance changes due to the substitution of metal elements.

[0214] In addition, CAAC-OS has a layered crystal structure in which a layer containing indium and oxygen (hereinafter, In layer) and a layer containing element M, zinc, and oxygen (hereinafter, (M,Zn) layer) are laminated. (also called layered structure). Indium and element M are mutually substitutable. When the element M in the (M,Zn) layer is replaced with indium, the (In,M,Zn) layer Also, when the indium in the In layer is replaced with element M, (In,M) It can also be expressed as a layer.

[0215] CAAC-OS is a highly crystalline oxide semiconductor. Since it is not possible to confirm the grain boundaries, the decrease in electron mobility caused by the grain boundaries occurs. In addition, the crystallinity of an oxide semiconductor is easily deteriorated due to the inclusion of impurities or the generation of defects. Therefore, CAAC-OS is an oxide semiconductor with few impurities and defects (oxygen vacancies, etc.). Therefore, the physical properties of oxide semiconductors having CAAC-OS are stable. Therefore, oxide semiconductors having CAAC-OS are resistant to heat and have high reliability. In addition, CAAC-OS is designed to withstand the high temperatures (so-called thermal budget) in the manufacturing process. Therefore, when CAAC-OS is used for an OS transistor, This allows for greater freedom.

[0216] nc-OS is a material that is used in microscopic regions (e.g., regions between 1 nm and 10 nm, especially regions between 1 nm and The atomic arrangement has periodicity in the region of 3 nm or less. There is no regularity in the crystal orientation between the crystals. Therefore, no orientation is observed throughout the film. Therefore, depending on the analysis method, nc-OS may be classified as a-like OS or amorphous oxide semiconductor. Sometimes it is indistinguishable from the body.

[0217] The a-like OS is an oxide semiconductor that has a structure between the nc-OS and the amorphous oxide semiconductor. It is a semiconductor. The a-like OS has a loose or low-density region. That is, the a-like OS has lower crystallinity compared to nc-OS and CAAC-OS.

[0218] Oxide semiconductors have various structures, each having different characteristics. One aspect of the present invention of the oxide semiconductor may have two or more of an amorphous oxide semiconductor, a polycrystalline oxide semiconductor, a-like OS, n c-OS, and CAAC-OS.

[0219] <Transistor having an oxide semiconductor> Subsequently, the case of using the above oxide semiconductor in a transistor will be described.

[0220] By using the above oxide semiconductor in a transistor, a transistor with high field-effect mobility can be realized. Also, a highly reliable transistor can be realized.

[0221] Also, for a transistor, it is preferable to use an oxide semiconductor with a low carrier concentration. When reducing the carrier concentration of the oxide semiconductor film, the impurity concentration in the oxide semiconductor film may be reduced, and the density of defect levels may be reduced. In this specification and the like, a low impurity concentration and a low density of defect levels are referred to as highly pure intrinsic or substantially highly pure intrinsic.

[0222] Also, an oxide semiconductor film that is highly pure intrinsic or substantially highly pure intrinsic has a low density of defect levels and thus the density of trap levels may also be low.

[0223] Also, the charge trapped in the trap levels of the oxide semiconductor may take a long time to disappear and may behave as if it were a fixed charge. Therefore, a high density of trap levels long, and may behave as if it were a fixed charge. Therefore, a high trap level density A transistor in which a channel formation region is formed in an oxide semiconductor may have unstable electrical characteristics. There are cases where this occurs.

[0224] Therefore, in order to stabilize the electrical characteristics of the transistor, it is effective to reduce the impurity concentration in the oxide semiconductor. Also, in order to reduce the impurity concentration in the oxide semiconductor, it is preferable to also reduce the impurity concentration in the adjacent film. Examples of impurities include hydrogen, nitrogen, alkali metals, alkaline earth metals, iron, nickel, silicon, and the like.

[0225] <Impurities> Here, the effects of various impurities in the oxide semiconductor will be described.

[0226] When silicon or carbon, which is one of the Group 14 elements, is contained in the oxide semiconductor, defect levels are formed in the oxide semiconductor. For this reason, the concentration of silicon or carbon in the oxide semiconductor and the concentration of silicon or carbon near the interface with the oxide semiconductor (the concentration obtained by secondary ion mass spectrometry (SIMS: Secondary Ion Mass Spectrometry)) are set to 2×10 atoms / cm or less, preferably 2×10 atoms / cm 18 or less. 3 17 a toms / cm 3 or less.

[0227] Also, when an alkali metal or an alkaline earth metal is contained in the oxide semiconductor, defect levels may be formed and carriers may be generated. Therefore, a transistor using an oxide semiconductor containing an alkali metal or an alkaline earth metal tends to have normally-on characteristics. For this reason, it is necessary to reduce the concentration of alkali metal or alkaline earth metal in the oxide semiconductor. It is preferable. Specifically, the concentration of alkali metal or alkaline earth metal in the oxide semiconductor obtained by SIMS is 1×10 18 atoms / cm 3 or less, preferably 2×10 16 atoms / cm 3 or less.

[0228] In addition, in the oxide semiconductor, when nitrogen is contained, electrons as carriers are generated, and the carrier concentration increases, and it tends to be n-type. As a result, a transistor using an oxide semiconductor containing nitrogen tends to have normally-on characteristics. Therefore, in the oxide semiconductor, it is preferable that nitrogen is reduced as much as possible. For example, the nitrogen concentration in the oxide semiconductor is less than 5×10 19 atoms / cm 3 , preferably 5× 10 18 atoms / cm 3 or less, more preferably 1×10 18 atoms / cm 3 or less , even more preferably 5×10 17 atoms / cm 3 or less.

[0229] In addition, hydrogen contained in the oxide semiconductor may react with oxygen bonded to metal atoms to form water, resulting in the formation of oxygen vacancies. When hydrogen enters these oxygen vacancies, carriers, i.e., electrons, may be generated. Also, a part of hydrogen may bond with oxygen bonded to metal atoms to generate carriers, i.e., electrons. Therefore, a transistor using an oxide semiconductor containing hydrogen tends to have normally-on characteristics. For this reason, it is preferable that hydrogen in the oxide semiconductor is reduced as much as possible. Specifically, in the oxide semiconductor, The hydrogen concentration obtained by SIMS is less than 1×10 20 atoms / cm 3 , preferably less than 1×10 19 atoms / cm 3 , more preferably less than 5×10 18 atoms / cm 3 , still more preferably less than 1×10 18 atoms / cm 3 .

[0230] By using an oxide semiconductor with sufficiently reduced impurities in the channel formation region of the transistor, stable electrical characteristics can be imparted.

[0231] This embodiment can be implemented in appropriate combination with the configurations described in other embodiments etc. .

[0232] (Embodiment 4) In this embodiment, a memory device using the semiconductor device 10 described in Embodiment 1 will be described. .

[0233] [Memory Device] FIG. 20 is a block diagram showing a configuration example of a memory device. The memory device 30 includes a peripheral circuit 31 and a cell array 51. The peripheral circuit 31 includes a row decoder 32, a word line driver circuit 33, a bit line driver circuit 34, an output circuit 35, and a control logic circuit 36 .

[0234] The word line driver circuit 33 has a function of supplying a potential to the wiring WL. The bit line driver circuit 34 includes a column decoder 41, a precharge circuit 42, an amplifier circuit 43, and a write circuit 44. The precharge circuit 42 has a function of precharging the wiring RL etc. It has a function. The amplification circuit 43 has a function of amplifying the data signal read from the wiring RL. Note that the wiring WWL, the wiring RWL, the wiring SL, the wiring BL, and the wiring RL are wirings connected to the semiconductor device 10 that functions as a memory cell included in the cell array 51, as described in the first embodiment. The amplified data signal is output to the outside of the storage device 30 as a digital data signal RDATA via the output circuit 35.

[0235] A low power supply voltage (VSS) as a power supply voltage from the outside, a high power supply voltage (VDD) for the peripheral circuit 31, and a high power supply voltage (VIL) for the cell array 51 are supplied to the storage device 30.

[0236] In addition, a control signal (CE, WE, RE), an address signal ADDR, and a data signal WDATA are input to the storage device 30 from the outside. The address signal ADDR is input to the row decoder 32 and the column decoder 41, and the WDATA is input to the write circuit 44.

[0237] The control logic circuit 36 processes the input signals (CE, WE, RE) from the outside and generates control signals for the row decoder 32 and the column decoder 41. CE is a chip enable signal, WE is a write enable signal, and RE is a read enable signal. The signals processed by the control logic circuit 36 are not limited to these, and other control signals may be input as necessary.

[0238] Note that each of the above circuits or signals can be appropriately selected or discarded as necessary.

[0239] OS transistors can be applied to the transistors constituting the cell array 51. In addition, an OS transistor can be applied to the transistors constituting the peripheral circuit 31. . By forming the cell array 51 and the peripheral circuit 31 using OS transistors, the cell array 51 and the peripheral circuit 31 can be fabricated in the same manufacturing process, and the manufacturing cost can be kept low.

[0240] 〔Configuration Example of Cell Array〕 The details of the cell array 51 are described in FIG. 21. The cell array 51 includes m (where m is an integer of 1 or more .) semiconductor devices 10 that function as memory cells in each column and n (where n is an integer of 1 or more.) semiconductor devices 10 that function as memory cells in each row, for a total of m × n semiconductor devices 10. The semiconductor devices 10 are arranged in a matrix as exemplified in FIGS. 10, 12, and 1 4. In FIG. 21, the addresses of the semiconductor devices 10 are also shown, and the semiconductor devices 10 located at the addresses of [1,1], [m,1], [i,j], [1,n], [m,n] (where i is an integer from 1 to m and j is an integer from 1 to n.) are illustrated. Note that the number of wirings connecting the cell array 51 and the word line driver circuit 33 is determined by the configuration of the semiconductor device 10, the number of semiconductor devices 10 included in a column, etc. Also, the number of wirings connecting the cell array 51 and the bit line driver circuit 34 is determined by the configuration of the semiconductor device 10, the number of semiconductor devices 10 included in a row, etc. By configuring the semiconductor device 10, data can be rewritten and read by charging or discharging electric charges, so that data can be written and read substantially an unlimited number of times. When reading data, discharging the stored electric charge, so-called

[0241] Since data can be read without soft destruction reading, the power consumption for charging and discharging the required charge for data refresh can be reduced.

[0242] Also, by configuring the semiconductor device 10, the amount of charge required for rewriting data can be reduced. Therefore, data can be read without discharging the stored charge to a wiring or the like having a large capacitance. Also, a semiconductor device excellent in reliability such as long-term data retention can be provided.

[0243] (Embodiment 5) This embodiment shows an example of an electronic component and an electronic device in which a storage device or the like shown in the above embodiment is incorporated.

[0244] <Electronic Component> First, an example of an electronic component in which a storage device 300 is incorporated will be described with reference to FIGS. 22A and 22B.

[0245] FIG. 22A shows a perspective view of an electronic component 700 and a substrate (mounting substrate 704) on which the electronic component 700 is mounted. The electronic component 700 shown in FIG. 22A is an IC chip and has leads and a circuit section. The electronic component 700 is mounted on, for example, a printed circuit board 702. A plurality of such IC chips are combined and electrically connected to each other on the printed circuit board 702, thereby completing the mounting substrate 704.

[0246] The storage device 30 shown in the above embodiment is provided as the circuit section of the electronic component 700. In FIG. 22A, a QFP (Quad Flat Pac kage) is applied to the package of the electronic component 700, but the package form is not limited to this. The storage device is Si A layer 61 provided with transistors and a layer 62 provided with OS transistors are laminated. Yes.

[0247] Fig. 22B shows a perspective view of the electronic component 730. The electronic component 730 is an example of a SiP (System in package) or an MCM (Multi Chip Module). In the electronic component 730, an interposer 731 is provided on a package substrate 732 (printed circuit board), and a semiconductor device 735 and a plurality of storage devices 30 are provided on the interposer 731.

[0248] In the electronic component 730, an example of using the storage device 30 as a high-bandwidth memory (HBM: High Bandwi dth Memory) is shown. In addition, for the semiconductor device 735, C PU (Central Processing Unit), GPU (Graphic Processing Unit), FPGA (Field Programmable Gate Array) and other integrated circuits (semiconductor devices) can be used.

[0249] The package substrate 732 can use a ceramic substrate, a plastic substrate, a glass epoxy substrate, etc. For the interposer 731, a silicon interposer, a resin interposer, etc. can be used.

[0250] The interposer 731 has a plurality of wirings and has a function of electrically connecting a plurality of integrated circuits with different terminal pitches. The plurality of wirings are provided in a single layer or multiple layers. Also, the inter poser 731 electrically connects the integrated circuits provided on the interposer 731 to the package substrate 7 32. It has a function of electrically connecting to the electrode provided at 32. From these facts, the interposer may sometimes be referred to as a "rewiring substrate" or an "intermediate substrate". Also, the interposer 73 1 may be provided with through electrodes, and the integrated circuit and the package substrate 732 may be electrically connected using the through electrodes. Also, in a silicon interposer, TSV ( Through Silicon Via) can also be used as the through electrode.

[0251] It is preferable to use a silicon interposer as the interposer 731. Since it is not necessary to provide active elements in a silicon interposer, it can be manufactured at a lower cost than an integrated circuit. On the other hand, since the wiring formation of a silicon interposer can be performed by a semiconductor process, it is easy to form fine wiring, which is difficult in a resin interposer.

[0252] In HBM, many wirings need to be connected to realize a wide memory bandwidth. Therefore, for the interposer on which HBM is mounted, formation of fine and high-density wiring is required. Therefore, it is preferable to use a silicon interposer for the interposer on which HBM is mounted.

[0253] Also, in SiP, MCM, etc. using a silicon interposer, a decrease in reliability due to a difference in the coefficient of thermal expansion between the integrated circuit and the interposer rarely occurs. Also, since the silicon interposer has high surface flatness, connection failure between the integrated circuit provided on the silicon interposer and the silicon interposer rarely occurs. In particular, in a 2.5D package (2.5-dimensional mounting) in which a plurality of integrated circuits are arranged side by side on the interposer , it is preferable to use a silicon interposer. ​

[0254] Also, a heat sink (heat dissipation plate) may be provided so as to overlap with the electronic component 730. When providing the heat sink it is preferable to align the heights of the integrated circuits provided on the interposer 731. For example, in the electronic component 730 shown in the present embodiment, it is preferable to align the heights of the storage device 30 and the semiconductor device 735

[0255] In order to mount the electronic component 730 on another substrate, electrodes 733 may be provided at the bottom of the package substrate 732 An example of forming the electrodes 733 with solder balls is shown in FIG. 22B. By providing solder balls in a matrix pattern at the bottom of the package substrate 732, BGA (Bal l Grid Array) mounting can be realized. Also, the electrodes 733 may be formed with conductive pins By providing conductive pins in a matrix pattern at the bottom of the package substrate 732 PGA (Pin Grid Array) mounting can be realized.

[0256] The electronic component 730 can be mounted on other substrates using various mounting methods not limited to BGA and PGA. For example, SPGA (Staggered Pin Grid Ar ray), LGA (Land Grid Array), QFP (Quad Flat Package), QFJ (Quad Flat J-leaded package) or QFN (Quad Flat Non-leaded package) etc. mounting methods can be used.

[0257] <Electronic device> Next, an example of an electronic device including the above electronic component will be described with reference to FIG. 23.

[0258] ​​​​The robot 7100 is equipped with an illuminance sensor, a microphone, a camera, a speaker, and a display. It also has various sensors (such as an infrared sensor, an ultrasonic sensor, an acceleration sensor, a piezo sensor, a light sensor, a gyro sensor, etc.), and a moving mechanism. The electronic component 730 has a processor and has the function of controlling these peripheral devices. For example, the electronic component 700 has the function of storing data obtained by the sensors.

[0259] The microphone has the function of detecting acoustic signals such as the user's voice and environmental sounds. Also, the speaker has the function of emitting audio signals such as voice and warning sounds. The robot 7100 can analyze the audio signals input via the microphone and emit the necessary audio signals from the speaker. In the robot 7100, it is possible to communicate with the user using the microphone and the speaker.

[0260] The camera has the function of imaging the surroundings of the robot 7100. Also, the robot 7100 has the function of moving using the moving mechanism. The robot 7100 can use the camera to image the surrounding images and analyze the images to detect the presence or absence of obstacles when moving.

[0261] The flying object 7120 has a propeller, a camera, and a battery, etc., and has the function of autonomous flight. The electronic component 730 has the function of controlling these peripheral devices.

[0262] For example, the image data captured by the camera is stored in the electronic component 700. The electronic component 73 0 can analyze the image data and detect the presence or absence of obstacles when moving. Further, the remaining battery level can be estimated from the change in the battery's storage capacity by the electronic component 730. This is possible.

[0263] The cleaning robot 7140 has a display disposed on the upper surface, a plurality of cameras, brushes, operation buttons, various sensors, etc. disposed on the side surface. Although not shown, the cleaning robot 7140 is provided with tires, a suction port, etc. The cleaning robot 7140 can move automatically, detect dust, and suck dust from the suction port provided on the lower surface. For example, the electronic component 730 can analyze the image captured by the camera and determine the presence or absence of obstacles such as walls, furniture, or steps. Also, when an object likely to get caught in the brush, such as wiring, is detected by image analysis, the rotation of the brush can be stopped. The cleaning robot 7140 can move automatically, detect dust, and suck dust from the suction port provided on the lower surface. For example, the electronic component 730 can analyze the image captured by the camera and determine the presence or absence of obstacles such as walls, furniture, or steps. Also, when an object likely to get caught in the brush, such as wiring, is detected by image analysis, the rotation of the brush can be stopped.

[0264] For example, the electronic component 730 can analyze the image captured by the camera and determine the presence or absence of obstacles such as walls, furniture, or steps. Also, when an object likely to get caught in the brush, such as wiring, is detected by image analysis, the rotation of the brush can be stopped. For example, the electronic component 730 can analyze the image captured by the camera and determine the presence or absence of obstacles such as walls, furniture, or steps. Also, when an object likely to get caught in the brush, such as wiring, is detected by image analysis, the rotation of the brush can be stopped. For example, the electronic component 730 can analyze the image captured by the camera and determine the presence or absence of obstacles such as walls, furniture, or steps. Also, when an object likely to get caught in the brush, such as wiring, is detected by image analysis, the rotation of the brush can be stopped.

[0265] The automobile 7160 has an engine, tires, brakes, a steering device, a camera, etc. For example, the electronic component 730 performs control to optimize the driving state of the automobile 7160 based on data such as navigation information, speed, engine state, gear selection state, and brake usage frequency. For example, the image data captured by the camera is stored in the electronic component 700. For example, the electronic component 730 performs control to optimize the driving state of the automobile 7160 based on data such as navigation information, speed, engine state, gear selection state, and brake usage frequency. For example, the image data captured by the camera is stored in the electronic component 700. For example, the electronic component 730 performs control to optimize the driving state of the automobile 7160 based on data such as navigation information, speed, engine state, gear selection state, and brake usage frequency. For example, the image data captured by the camera is stored in the electronic component 700. For example, the electronic component 730 performs control to optimize the driving state of the automobile 7160 based on data such as navigation information, speed, engine state, gear selection state, and brake usage frequency. For example, the image data captured by the camera is stored in the electronic component 700. This is possible.

[0266] The electronic component 700 and / or the electronic component 730 can be incorporated into a TV device 7200 (television receiving image device), a smartphone 7210, a PC (personal computer) 7220, 7230, a game machine 7240, a game machine 7260, etc. For example, the electronic component 730 incorporated in the TV device 7200 functions as an image engine. This is possible.

[0267] For example, the electronic component 730 incorporated in the TV device 7200 functions as an image engine. It can be done. For example, the electronic component 730 performs image processing such as noise removal and resolution up-conversion. and the like.

[0268] The smartphone 7210 is an example of a mobile information terminal. The smartphone 7210 has a microphone, a camera, a speaker, various sensors, and a display unit. These peripheral devices are controlled by the electronic component 73 0.

[0269] The PCs 7220 and 7230 are examples of a notebook PC and a desktop PC, respectively. The PC 7230 can be connected to a keyboard 7232 and a monitor device 7233 either wirelessly or by wire. The game machine 7240 is an example of a portable game machine. The game machine 7260 is an example of a desktop game machine. A controller 7262 is connected to the game machine 7260 either wirelessly or by wire. The electronic component 700 and / or the electronic component 730 can also be incorporated into the controller 7262.

[0270] This embodiment can be implemented in appropriate combination with the configurations described in other embodiments and the like.

[0271] (Supplementary Note Regarding the Descriptions in this Specification, etc.) Regarding the above embodiments and the descriptions of each configuration in the embodiments, the following supplementary notes are provided.

[0272] The configurations shown in each embodiment can be appropriately combined with the configurations shown in other embodiments or examples to form an aspect of the present invention. Also, when multiple configuration examples are shown in one embodiment, it is possible to appropriately combine the configuration examples.

[0273] Note that the content described in one embodiment (which may be part of the content) can be applied to, combined with, or replaced with the content described in another embodiment (which may be part of the content), and / or the content described in one or more other embodiments (which may be part of the content). Note that the content described in one embodiment (which may be part of the content) can be applied to, combined with, or replaced with the content described in another embodiment (which may be part of the content), and / or the content described in one or more other embodiments (which may be part of the content). Note that the content described in one embodiment (which may be part of the content) can be applied to, combined with, or replaced with the content described in another embodiment (which may be part of the content), and / or the content described in one or more other embodiments (which may be part of the content). Note that the content described in one embodiment (which may be part of the content) can be applied to, combined with, or replaced with the content described in another embodiment (which may be part of the content), and / or the content described in one or more other embodiments (which may be part of the content).

[0274] Note that the content described in the embodiments refers to the content described using various figures in each embodiment or the content described using the text described in the specification. Note that the content described in the embodiments refers to the content described using various figures in each embodiment or the content described using the text described in the specification.

[0275] Note that the figure (which may be part of it) described in one embodiment can be combined with another part of the figure, another figure (which may be part of it) described in that embodiment, and / or the figure (which may be part of it) described in one or more other embodiments to form more figures. Note that the figure (which may be part of it) described in one embodiment can be combined with another part of the figure, another figure (which may be part of it) described in that embodiment, and / or the figure (which may be part of it) described in one or more other embodiments to form more figures. Note that the figure (which may be part of it) described in one embodiment can be combined with another part of the figure, another figure (which may be part of it) described in that embodiment, and / or the figure (which may be part of it) described in one or more other embodiments to form more figures. Note that the figure (which may be part of it) described in one embodiment can be combined with another part of the figure, another figure (which may be part of it) described in that embodiment, and / or the figure (which may be part of it) described in one or more other embodiments to form more figures.

[0276] In addition, in this specification, etc., in the block diagram, components are classified by function and shown as independent blocks. However, in an actual circuit, etc., it is difficult to divide components by function, and there may be cases where a single circuit is related to multiple functions or a single function is related to multiple circuits. Therefore, the blocks in the block diagram are not limited to the components described in the specification and can be appropriately rephrased according to the situation. In addition, in this specification, etc., in the block diagram, components are classified by function and shown as independent blocks. However, in an actual circuit, etc., it is difficult to divide components by function, and there may be cases where a single circuit is related to multiple functions or a single function is related to multiple circuits. Therefore, the blocks in the block diagram are not limited to the components described in the specification and can be appropriately rephrased according to the situation. In addition, in this specification, etc., in the block diagram, components are classified by function and shown as independent blocks. However, in an actual circuit, etc., it is difficult to divide components by function, and there may be cases where a single circuit is related to multiple functions or a single function is related to multiple circuits. Therefore, the blocks in the block diagram are not limited to the components described in the specification and can be appropriately rephrased according to the situation. In addition, in this specification, etc., in the block diagram, components are classified by function and shown as independent blocks. However, in an actual circuit, etc., it is difficult to divide components by function, and there may be cases where a single circuit is related to multiple functions or a single function is related to multiple circuits. Therefore, the blocks in the block diagram are not limited to the components described in the specification and can be appropriately rephrased according to the situation. In addition, in this specification, etc., in the block diagram, components are classified by function and shown as independent blocks. However, in an actual circuit, etc., it is difficult to divide components by function, and there may be cases where a single circuit is related to multiple functions or a single function is related to multiple circuits. Therefore, the blocks in the block diagram are not limited to the components described in the specification and can be appropriately rephrased according to the situation.

[0277] In the drawings, the size, layer thickness, or area is shown as an arbitrary size for the convenience of explanation. Therefore, it is not necessarily limited to that scale. Note that the drawings are shown schematically for clarity and are not limited to the shapes or values shown in the drawings. For example In the drawings, the size, layer thickness, or area is shown as an arbitrary size for the convenience of explanation. Therefore, it is not necessarily limited to that scale. Note that the drawings are shown schematically for clarity and are not limited to the shapes or values shown in the drawings. For example In the drawings, the size, layer thickness, or area is shown as an arbitrary size for the convenience of explanation. Therefore, it is not necessarily limited to that scale. Note that the drawings are shown schematically for clarity and are not limited to the shapes or values shown in the drawings. For example , variations in signals, voltages, or currents due to noise, or variations in signals, voltages, or currents due to timing shifts, etc. can be included. It is possible to include variations in signals, voltages, or currents due to noise, or variations in signals, voltages, or currents due to timing shifts, etc.

[0278] Also, the positional relationships of the components illustrated in the drawings and the like are relative. Therefore, when explaining the components with reference to the drawings, terms such as "above" and "below" indicating positional relationships may be used for convenience. The positional relationships of the components are not limited to the description in this specification and can be appropriately rephrased according to the situation. When explaining the connection relationships of transistors in this specification and the like, the notation "one of the source or drain" (or the first electrode, or the first terminal), and the other of the source and drain as "the other of the source or drain" (or the second electrode, or the second terminal) is used. This is because the source and drain of a transistor can change depending on the structure or operating conditions of the transistor, etc. Regarding the names of the source and drain of a transistor, they can be appropriately rephrased according to the situation, such as the source (drain) terminal or the source (drain) electrode. In this specification and the like, the terms "electrode" and "wiring" do not functionally limit these components. For example, an "electrode" may be used as part of a "wiring", and vice versa. Furthermore, the terms "electrode" and "wiring" also include cases where a plurality of "electrodes" and "wirings" are integrally formed. Also, in this specification and the like, voltage and potential can be appropriately rephrased. Voltage is the potential difference from a reference potential. For example, when the reference potential is the ground voltage (ground

[0279] When explaining the connection relationships of transistors in this specification and the like, the notation "one of the source or drain" (or the first electrode, or the first terminal), and the other of the source and drain as "the other of the source or drain" (or the second electrode, or the second terminal) is used. This is because the source and drain of a transistor can change depending on the structure or operating conditions of the transistor, etc. Regarding the names of the source and drain of a transistor, they can be appropriately rephrased according to the situation, such as the source (drain) terminal or the source (drain) electrode. When explaining the connection relationships of transistors in this specification and the like, the notation "one of the source or drain" (or the first electrode, or the first terminal), and the other of the source and drain as "the other of the source or drain" (or the second electrode, or the second terminal) is used. This is because the source and drain of a transistor can change depending on the structure or operating conditions of the transistor, etc. Regarding the names of the source and drain of a transistor, they can be appropriately rephrased according to the situation, such as the source (drain) terminal or the source (drain) electrode. When explaining the connection relationships of transistors in this specification and the like, the notation "one of the source or drain" (or the first electrode, or the first terminal), and the other of the source and drain as "the other of the source or drain" (or the second electrode, or the second terminal) is used. This is because the source and drain of a transistor can change depending on the structure or operating conditions of the transistor, etc. Regarding the names of the source and drain of a transistor, they can be appropriately rephrased according to the situation, such as the source (drain) terminal or the source (drain) electrode. When explaining the connection relationships of transistors in this specification and the like, the notation "one of the source or drain" (or the first electrode, or the first terminal), and the other of the source and drain as "the other of the source or drain" (or the second electrode, or the second terminal) is used. This is because the source and drain of a transistor can change depending on the structure or operating conditions of the transistor, etc. Regarding the names of the source and drain of a transistor, they can be appropriately rephrased according to the situation, such as the source (drain) terminal or the source (drain) electrode. When explaining the connection relationships of transistors in this specification and the like, the notation "one of the source or drain" (or the first electrode, or the first terminal), and the other of the source and drain as "the other of the source or drain" (or the second electrode, or the second terminal) is used. This is because the source and drain of a transistor can change depending on the structure or operating conditions of the transistor, etc. Regarding the names of the source and drain of a transistor, they can be appropriately rephrased according to the situation, such as the source (drain) terminal or the source (drain) electrode. When explaining the connection relationships of transistors in this specification and the like, the notation "one of the source or drain" (or the first electrode, or the first terminal), and the other of the source and drain as "the other of the source or drain" (or the second electrode, or the second terminal) is used. This is because the source and drain of a transistor can change depending on the structure or operating conditions of the transistor, etc. Regarding the names of the source and drain of a transistor, they can be appropriately rephrased according to the situation, such as the source (drain) terminal or the source (drain) electrode.

[0280] When explaining the connection relationships of transistors in this specification and the like, the notation "one of the source or drain" (or the first electrode, or the first terminal), and the other of the source and drain as "the other of the source or drain" (or the second electrode, or the second terminal) is used. This is because the source and drain of a transistor can change depending on the structure or operating conditions of the transistor, etc. Regarding the names of the source and drain of a transistor, they can be appropriately rephrased according to the situation, such as the source (drain) terminal or the source (drain) electrode. When explaining the connection relationships of transistors in this specification and the like, the notation "one of the source or drain" (or the first electrode, or the first terminal), and the other of the source and drain as "the other of the source or drain" (or the second electrode, or the second terminal) is used. This is because the source and drain of a transistor can change depending on the structure or operating conditions of the transistor, etc. Regarding the names of the source and drain of a transistor, they can be appropriately rephrased according to the situation, such as the source (drain) terminal or the source (drain) electrode. When explaining the connection relationships of transistors in this specification and the like, the notation "one of the source or drain" (or the first electrode, or the first terminal), and the other of the source and drain as "the other of the source or drain" (or the second electrode, or the second terminal) is used. This is because the source and drain of a transistor can change depending on the structure or operating conditions of the transistor, etc. Regarding the names of the source and drain of a transistor, they can be appropriately rephrased according to the situation, such as the source (drain) terminal or the source (drain) electrode. When explaining the connection relationships of transistors in this specification and the like, the notation "one of the source or drain" (or the first electrode, or the first terminal), and the other of the source and drain as "the other of the source or drain" (or the second electrode, or the second terminal) is used. This is because the source and drain of a transistor can change depending on the structure or operating conditions of the transistor, etc. Regarding the names of the source and drain of a transistor, they can be appropriately rephrased according to the situation, such as the source (drain) terminal or the source (drain) electrode.

[0281] When explaining the connection relationships of transistors in this specification and the like, the notation "one of the source or drain" (or the first electrode, or the first terminal), and the other of the source and drain as "the other of the source or drain" (or the second electrode, or the second terminal) is used. This is because the source and drain of a transistor can change depending on the structure or operating conditions of the transistor, etc. Regarding the names of the source and drain of a transistor, they can be appropriately rephrased according to the situation, such as the source (drain) terminal or the source (drain) electrode. When explaining the connection relationships of transistors in this specification and the like, the notation "one of the source or drain" (or the first electrode, or the first terminal), and the other of the source and drain as "the other of the source or drain" (or the second electrode, or the second terminal) is used. This is because the source and drain of a transistor can change depending on the structure or operating conditions of the transistor, etc. Regarding the names of the source and drain of a transistor, they can be appropriately rephrased according to the situation, such as the source (drain) terminal or the source (drain) electrode. If the voltage is set to a certain value, the voltage can be rephrased as electric potential. The ground potential does not necessarily mean 0V. Note that electric potential is relative, and depending on the reference electric potential, the electric potential applied to wiring or the like may change.

[0282] Also, in this specification and the like, a node can be rephrased as a terminal, wiring, electrode, conductive layer, conductor, impurity region, etc., according to the circuit configuration, device structure, etc. Further, it is possible to rephrase a terminal, wiring, etc. as a node.

[0283] In this specification and the like, "A and B are connected" means that A and B are electrically connected. Here, "A and B are electrically connected" means that when there is an object (an element such as a switch, transistor element, or diode, or a circuit including the element and wiring) between A and B, the transmission of an electrical signal between A and B is possible, which is called continuity. Note that when A and B are electrically connected, it includes the case where A and B are directly connected. Here, "A and B are directly connected" means a connection in which the transmission of an electrical signal between A and B is possible through a wiring (or electrode) or the like between A and B without passing through the above object. In other words, direct connection means a connection that can be regarded as the same circuit diagram when represented by an equivalent circuit.

[0284]

[0285]

[0284] In this specification and the like, a switch refers to something that can be in a conductive state (on state) or a non-conductive state (off state) and has a function of controlling whether to allow current to flow or not. Or, a switch refers to something that has a function of selecting and switching a path for current to flow.

[0285]

[0285] In this specification and the like, the channel length refers to, for example, in the top view of a transistor, the distance between the source and the drain in the region where the semiconductor (or the part where current flows in the semiconductor when the transistor is in the on state) and the gate overlap, or in the region where the channel is formed. In this specification and the like, the channel width refers to, for example, in the region where the semiconductor (or the part where current flows in the semiconductor when the transistor is in the on state) and the gate electrode overlap, or in the region where the channel is formed, the length of the portion where the source and the drain face each other. In this specification and the like, the terms such as "film" and "layer" can be interchanged with each other depending on the case or situation. For example, the term "conductive layer" may be changed to the term "conductive film". Or, for example, the term "insulating film" may be changed to the term "insulating layer".

[0286]

[0287] [Explanation of Reference Numerals]

[0288] BL_1: Wiring, MN1: Node, MN2: Node, RL_1: Wiring, RWL_1: Wiring, SL_1: Wiring, SL_2: Wiring, T1: Period, T2: Period, T3: Period, T4: Period, T5: Period, T6: Period, T7: Period, T8: Period, T9: Period, WWL_1: Wiring, WWL_2: Wiring, 10: Semiconductor Device, 10_1: Semiconductor Device, 10_4: Semiconductor Device, 10A: Semiconductor Device, 10B: Semiconductor Device, 10C: Semiconductor Device, 10D: Semiconductor Device, 10E: Semiconductor Device, 10F: Semiconductor Device, 10G: Semiconductor Device, 11: Transistor , 11A: Transistor, 11B: Transistor, 11C: Transistor, 11D: Trans istor, 11E: Transistor, 11F: Transistor, 11G: Transistor, 12 : Transistor, 12A: Transistor, 12B: Transistor, 12C: Transistor , 12D: Transistor, 12E: Transistor, 12F: Transistor, 12G: Trans istor, 13: Transistor, 13A: Transistor, 13B: Transistor, 13C : Transistor, 13D: Transistor, 13E: Transistor, 13G: Transistor , 14: Capacitor, 15: Charge holding circuit, 30: Memory device, 31: Peripheral circuit, 32: Lo wer decoder, 33: Word line driver circuit, 34: Bit line driver circuit, 35: Output cir cuit, 36: Control logic circuit, 41: Column decoder, 42: Precharge circuit , 43: Amplification circuit, 44: Circuit, 51: Cell array, 61: Layer, 62: Layer, 300: Memory device, 311: Substrate, 313: Semiconductor region, 314a: Low resistance region, 314b: Low resistance re gion, 315: Insulator, 316: Conductor, 320: Insulator, 322: Insulator, 324: Insul ator, 326: Insulator, 328: Conductor, 330: Conductor, 350: Insulator, 352: Insul ator, 354: Insulator, 356: Conductor, 360: Insulator, 362: Insulator, 364: Insul ator, 366: Conductor, 370: Insulator, 372: Insulator, 374: Insulator, 376: Conduct or, 380: Insulator, 382: Insulator, 384: Insulator, 386: Conductor, 402: Insul ator, 404: Insulator, 503: Conductor, 503a: Conductor, 503b: Conductor, 510: Insulator, 512: Insulator, 514: Insulator, 516: Insulator, 518: Conductor, 520: Insulator, 522: Insulator, 524: Insulator, 530: Oxide, 530a: Oxide, 530 b: Oxide, 530c: Oxide, 540a: Conductor, 540b: Conductor, 542: Conductor , 542a: Conductor, 542b: Conductor, 543a: Region, 543b: Region, 544: Insulator Insulator, 546: Conductor, 548: Conductor, 550: Insulator, 552: Insulator, 560: Conductor 560a: Conductor, 560b: Conductor, 574: Insulator, 580: Insulator, 581 : Insulator, 582: Insulator, 586: Insulator, 610: Conductor, 612: Conductor, 620 : Conductor, 630: Insulator, 640: Insulator, 700: Electronic component, 702: Printed circuit board , 704: Mounting substrate, 730: Electronic component, 731: Interposer, 732: Package Substrate, 733: Electrode, 735: Semiconductor device, 7100: Robot, 7120: Aircraft, 7 140: Cleaning robot, 7160: Automobile, 7200: TV device, 7210: Smart phone , 7220: PC, 7230: PC, 7232: Keyboard, 7233: Monitor device , 7240: Game console, 7260: Game console, 7262: Controller

Claims

[Claim 1] a first transistor, one of a source and a drain of which is electrically connected to a first wiring for reading data; a second transistor, one of a source or a drain of which is electrically connected to the gate of the first transistor and the other of which is electrically connected to a second wiring for writing data; a third transistor, one of a source or a drain of which is electrically connected to the gate of the first transistor, and the other of the source or the drain of which is electrically connected to a capacitor for holding a charge according to the data; The third transistor has a metal oxide in a channel formation region.

Images