Semiconductor device

Abstract

To provide a small semiconductor device.SOLUTION: The semiconductor device includes a first layer, a second layer, and a third layer formed over a substrate. The first transistor included in the first layer includes a first semiconductor layer containing Si. The second transistor included in the second layer includes a second semiconductor layer containing Ga. The third transistor included in the third layer includes a third semiconductor layer containing at least one of In and Zn. A first semiconductor layer of the first transistor is formed using the substrate. The second semiconductor layer of the second transistor is formed using a crystal grown over the substrate. A third semiconductor layer of the third transistor is formed above the first semiconductor layer and the second semiconductor layer.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] Note that one embodiment of the present invention is not limited to the above technical fields. The technical field relates to an article, a method, or a manufacturing method. is a process, machine, manufacture, or composition of matter. This concerns the

[0003] In this specification and the like, a semiconductor device is a device that can function by utilizing semiconductor characteristics. Therefore, it refers to semiconductor elements such as transistors and diodes, and The circuit including the semiconductor device is also used in display devices, light-emitting devices, lighting devices, electro-optical devices, and communication devices. The devices and electronic equipment may contain semiconductor elements and semiconductor circuits. Semiconductor devices, light-emitting devices, lighting devices, electro-optical devices, imaging devices, communication devices, and electronic devices are also used. It is sometimes called a conductor device. [Background technology]

[0004] Smartphone, tablet, or goggle-type display (head-mounted) Portable information terminals, such as display terminals, are becoming increasingly popular. With the spread of mobile communication, various communication standards have been established. For example, the fourth generation mobile communication system The LTE-Advanced standard, known as (4G), has begun operation.

[0005] In recent years, electronic devices other than information terminals (e.g., in-vehicle electronic devices, household electrical appliances, housing IoT (Internet of Things) connects devices (such as buildings, buildings, or wearable devices) to the Internet. With the development of information technology such as the Internet of Things, the amount of data handled by electronic devices is increasing. In addition, there is a demand for improved communication speeds in electronic devices such as information terminals. .

[0006] To realize IoT, the number of electronic devices connected to the Internet will increase. It is necessary to increase the number of electronic devices that can be connected at the same time. Because it is connected to the internet, there is a time lag (or delay) in communication. Therefore, in order to accommodate various information technologies including IoT, communication speeds faster than 4G, The fifth generation mobile communication system (5G) will realize many simultaneous connections and short latency. New communication standards are being considered for 5G, which will be used in the 3.7 GHz band, 4.5 GHz band, and Communication frequencies in the 28GHz band are used.

[0007] In Patent Document 1, a semiconductor device is formed by stacking transistors containing different semiconductor materials. An apparatus is disclosed.

[0008] 5G compatible semiconductor devices include semiconductors that use one type of element, such as Si, as their main component, It is made using compound semiconductors that use multiple elements such as Ga and As as their main components. Furthermore, oxide semiconductors, which are a type of metal oxide, have been attracting attention.

[0009] In oxide semiconductors, the structure is neither single crystal nor amorphous, and is called CAAC (c-axis aligned ed (crystalline) structure and nc (nanocrystalline) structure The structure has been found (see Non-Patent Documents 1 and 2).

[0010] In Non-Patent Documents 1 and 2, a transistor is fabricated using an oxide semiconductor having a CAAC structure. Techniques for fabricating transistors are disclosed. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] International Publication No. 2015-147835 [Non-patent literature]

[0012] [Non-Patent Document 1] S. Yamazaki et al., “SID Symposium Digest of Technical Papers”, 2012, volume 43, issue 1, p.183-186 [Non-patent document 2] S. Yamazaki et al., “Japanese Journal of Applied Physics”, 2014, volume 53, Number 4S, p.04ED18-1-04ED18-10 Summary of the Invention [Problem to be solved by the invention]

[0013] It is known that electronic devices generate heat due to the increase in communication speed. Semiconductor devices have a problem of increasing leakage current and malfunctioning in high temperature environments. In addition, electronic devices connected to networks using 5G, including IoT, are becoming increasingly portable. The electronic equipment is required to be excellent and small in size. Power supply control devices that supply power for high-speed operation, signal processing control devices, and arithmetic processing devices This poses a problem that the electronic equipment becomes large because multiple devices such as a memory device and a memory are required.

[0014] An object of one embodiment of the present invention is to provide a novel semiconductor device or the like. Another object is to provide a semiconductor device with high productivity. One of the objectives is to provide a semiconductor device or the like with reduced power consumption. Another object of the present invention is to provide a semiconductor device or the like that operates stably. Another object of the present invention is to provide a semiconductor device or the like having high reliability. One of the challenges is to:

[0015] The description of these problems does not preclude the existence of other problems. One embodiment does not necessarily solve all of these problems. Problems other than these may be solved by the specification. It is obvious from the description, drawings, claims, etc. It is possible to extract other issues from the descriptions in the sections. [Means for solving the problem]

[0016] One aspect of the present invention is a semiconductor device having a first layer, a second layer, and a third layer formed on a substrate. The first layer includes a first transistor containing silicon (Si). The second layer has a second semiconductor layer containing Ga. The third layer has a third transistor containing at least one of In and Zn. The first semiconductor layer of the first transistor has a third semiconductor layer including the substrate. The second semiconductor layer of the second transistor is formed by crystal growth on the substrate. The third semiconductor layer of the third transistor is formed using a crystal. and the second semiconductor layer.

[0017] In the above structure, the third transistor has a region overlapping with the first transistor. Preferably, it is located at the position.

[0018] In the above structure, the third transistor has a region overlapping with the second transistor. Preferably, it is located at the position.

[0019] In the above structure, the semiconductor device further includes a fourth layer. The fourth semiconductor layer of the transistor includes at least one of In and Zn. The transistor is preferably disposed at a position having an overlapping area with the third transistor. stomach.

[0020] In the above configuration, a sensor is formed on the opposite side of the first layer from the side where the first transistor is formed. Preferably, a sub-module is arranged. [Effects of the Invention]

[0021] According to one embodiment of the present invention, a semiconductor device or the like with reduced power consumption can be provided. Alternatively, a semiconductor device with stable operation can be provided. It is possible to provide a semiconductor device with good productivity. Alternatively, a novel semiconductor device or the like can be provided. This makes it possible to provide a small semiconductor device.

[0022] The description of these effects does not preclude the existence of other effects. An embodiment does not necessarily have all of these effects. Effects other than these may be included in the description. The above is self-evident from the description, drawings, claims, etc. From the above descriptions, it is possible to extract other effects. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 1 is a diagram illustrating a semiconductor device. [Figure 2] FIG. 2 is a diagram illustrating the semiconductor device. [Figure 3] FIG. 3 is a diagram illustrating a semiconductor device. [Figure 4] FIG. 4 is a diagram illustrating a semiconductor device. [Figure 5] FIG. 5 is a diagram illustrating a semiconductor device. [Figure 6] 6A and 6B are diagrams illustrating a semiconductor device. [Figure 7] FIG. 7 is a diagram illustrating an example of the configuration of a wireless transceiver. [Figure 8] 8A and 8B are diagrams illustrating an example of the configuration of a wireless transceiver. [Figure 9] FIG. 9 is a diagram illustrating a configuration example of a semiconductor device. [Figure 10] FIG. 10 is a diagram illustrating a configuration example of a semiconductor device. [Figure 11] 11A to 11C are diagrams showing examples of the configuration of a transistor. [Figure 12] 12A to 12C are diagrams showing examples of the configuration of a transistor. [Figure 13] 13A to 13C are diagrams showing examples of the configuration of a transistor. [Figure 14] FIG. 14 is a diagram illustrating a configuration example of a semiconductor device. [Figure 15]Figure 15A is a diagram explaining the classification of IGZO crystal structures, Figure 15B is a diagram explaining the XRD spectrum of a CAAC-IGZO film, and Figure 15C is a diagram explaining the electron microbeam diffraction pattern of a CAAC-IGZO film. [Figure 16] Figure 16A is a top view of a semiconductor wafer, and Figure 16B is an enlarged view of a chip. [Figure 17] Fig. 17A is a flowchart illustrating an example of a manufacturing process for an electronic component, and Fig. 17B is a schematic perspective view of the electronic component. [Figure 18] FIG. 18 is a diagram illustrating an example of an electronic device. [Figure 19] 19A to 19F are diagrams showing an example of an electronic device. [Figure 20] Figure 20 shows the hierarchical structure of IoT networks and trends in required specifications. [Figure 21] Figure 21 is an image diagram of factory automation. [Figure 22] 22A to 22C are diagrams showing the structure of an OS-FET used in calculating the cutoff frequency. [Figure 23] FIG. 23 is a diagram showing the calculation results of the cutoff frequency of an OS-FET. DETAILED DESCRIPTION OF THE INVENTION

[0024] The embodiments will be described in detail with reference to the drawings. However, the present invention is not limited to the following description. and variations in form and details may be made without departing from the spirit and scope of the present invention. It will be readily apparent to those skilled in the art that modifications may be made to the present invention. It should not be construed as being limited to the description of the embodiments. In the drawings, the same reference numerals are used to designate the same parts or parts having similar functions. and the repeated explanation will be omitted.

[0025] In addition, the position, size, range, etc. of each component shown in the drawings etc. are to be clearly indicated in order to facilitate understanding of the invention. Therefore, the actual location, size, range, etc. may not be shown. The invention is not necessarily limited to the position, size, range, etc. disclosed in the drawings, etc. For example, in the actual manufacturing process, resist masks and other materials may be damaged unintentionally by etching or other processes. However, this may not be reflected in the diagram to make it easier to understand.

[0026] Also, in top views (also called "plan views") and perspective views, etc., the drawings are easy to understand. Therefore, descriptions of some components may be omitted.

[0027] In addition, the terms "electrode" and "wiring" used in this specification and the like refer to these components functionally. This is not a limitation. For example, an "electrode" may be used as part of a "wiring." , and vice versa. Furthermore, the terms "electrode" and "wiring" may be used interchangeably with "electrodes" and "wiring." This also includes cases where the wiring is formed integrally.

[0028] In this specification, the resistance value of a "resistor" may be determined by the length of the wiring. Alternatively, the resistance value may be determined by connecting a conductive layer having a different resistivity from the conductive layer used in the wiring. Alternatively, the resistance value can be determined by doping impurities into the semiconductor layer. There may be cases where this is decided.

[0029] In this specification, a "terminal" in an electric circuit refers to a terminal that is used to input or output a current. It refers to the part where voltage is input or output, or where signals are received or transmitted. In this case, a part of the wiring or electrode may function as a terminal.

[0030] In this specification, the terms "upper", "upper", "lower" and "lower" refer to the configuration. The positional relationship of the elements does not necessarily have to be directly above or below and directly adjacent to each other. For example, if you say "electrode B on insulating layer A," it means that electrode B is directly on insulating layer A. It is not necessary to form a layer other than the insulating layer A and the electrode B. Also, if the expression is "conductive layer D above conductive layer C," it means that conductive layer D is on top of conductive layer C. It is not necessary that the conductive layers C and D are formed in direct contact with each other, and other components may be included between the conductive layers C and D. In addition, the terms "above" and "below" do not mean that the components are arranged diagonally. This does not exclude cases where the

[0031] The source and drain functions may also be different when using transistors with different polarities. When the direction of current changes during circuit operation, they may be interchanged depending on the operating conditions. Therefore, it is difficult to determine which is the source and which is the drain. In this specification, the terms source and drain can be used interchangeably. It shall be.

[0032] In addition, in this specification, "electrically connected" refers to a direct connection and a connection without any This includes cases where the device is connected via "something that has an electrical effect." "Something with an electrical effect" means something that enables the transmission and reception of electrical signals between connected objects. Therefore, even if it is expressed as "electrically connecting," In real circuits, there are cases where there are no physical connections and only wires are extended. In addition, "direct connection" refers to the connection of wiring formed by different conductive layers via contacts. This includes cases where the two or more wirings are connected together and function as a single wiring.

[0033] In this specification, "parallel" means that two lines are at an angle of -10° to 10°. This means that the angle between -5° and 5° is also included. Also, "perpendicular" and "orthogonal" mean, for example, that two straight lines are at an angle of 80° or more and 100° or less. Therefore, it also includes cases where the angle is between 85° and 95°.

[0034] In this specification and elsewhere, counting values ​​and measurement values ​​are referred to as "the same," "the same," "etc." When we say "good" or "uniform," we mean plus or minus 2 unless otherwise specified. It is assumed that there is a 0% margin of error.

[0035] Also, a voltage is a potential between a certain potential and a reference potential (for example, a ground potential or a source potential). Therefore, voltage and potential can be used interchangeably. In this specification and the like, unless otherwise specified, voltage and potential can be interchanged. This shall be the case.

[0036] Even when written as "semiconductor," if the conductivity is sufficiently low, it may be called an "insulator." Therefore, it is possible to use "semiconductor" instead of "insulator." In this case, the boundary between "semiconductor" and "insulator" is vague, and it is difficult to make a strict distinction between the two. Therefore, the terms "semiconductor" and "insulator" in this specification can be read interchangeably. It may be possible.

[0037] Also, even if a material is written as a "semiconductor," if the material has a sufficiently high conductivity, it may be written as a "conductor." Therefore, it is possible to use "semiconductor" instead of "conductor." In this case, the boundary between "semiconductor" and "conductor" is vague, and it is difficult to make a strict distinction between the two. Therefore, the terms "semiconductor" and "conductor" in this specification can be read interchangeably. It may be possible.

[0038] In this specification, ordinal numbers such as "first" and "second" are used to avoid confusion of components. It does not indicate any order or ranking, such as the order of processes or stacking. In addition, even if a term is not accompanied by an ordinal number in this specification, etc., it is not a misreading of the constituent elements. To avoid confusion, ordinal numbers may be used in the claims. Even if a term has an ordinal number in the above example, a different ordinal number may be used in the claims. In addition, even if a term is accompanied by an ordinal number in this specification, In some cases, ordinal numbers may be omitted in patent claims, etc.

[0039] In this specification, the "on state" of a transistor refers to the state where the source of the transistor is This refers to a state in which the drain and the gate are considered to be electrically short-circuited (also called the "conducting state"). The "off state" of a transistor means that the source and drain of the transistor are electrically isolated. This refers to a state in which the circuit can be considered disconnected (also called a "non-conducting state").

[0040] In this specification, the term "on-state current" refers to the amount of current that flows through the source when a transistor is in an on-state. The term "off-state current" may refer to the current that flows between the gate and drain of a transistor. It may refer to the current that flows between the source and drain when the device is in the off state.

[0041] In this specification, a high power supply voltage VDD (hereinafter simply referred to as "VDD", "H voltage", or "H") refers to the low power supply voltage VSS (hereinafter simply referred to as "VSS", "L voltage", VSS refers to a power supply voltage that is higher than VDD. It also refers to the power supply voltage that is lower than the ground voltage (hereafter simply referred to as "GND" or "GN For example, the VDD voltage (also called the "power supply voltage") can be used as VDD or VSS. In the case of earth voltage, VSS is a voltage lower than the ground voltage, and in the case of VSS is ground voltage , VDD is a voltage higher than the ground voltage.

[0042] In this specification, the term "gate" refers to a gate electrode and a part or all of a gate wiring. The gate wiring is the part that is connected to the gate electrode of at least one transistor and another This refers to wiring that electrically connects electrodes or other wiring.

[0043] In this specification, the source includes a source region, a source electrode, and a source wiring. The source region is the part of the semiconductor layer where the resistivity is below a certain value. The source electrode refers to the conductive layer connected to the source region. The source wiring is a wiring that connects the source electrode of at least one transistor with another electrode or another wiring. This refers to wiring that electrically connects wires.

[0044] In this specification, the drain includes a drain region, a drain electrode, and a drain electrode. The drain region is a part or all of the semiconductor layer with a resistivity of The drain electrode is the conductive part connected to the drain region. The drain wiring is the layer that is connected to the drain electrode of at least one transistor. , refers to wiring for electrically connecting to another electrode or another wiring.

[0045] In addition, in drawings, etc., the voltages of the wiring and electrodes are shown in order to make them easier to understand. When adding "H" to indicate H voltage or "L" to indicate L voltage next to an electrode, etc. In addition, wiring and electrodes where a voltage change occurs are marked with "H" or "L" in brackets. When a transistor is in the off state, the transistor An "x" symbol may be added over the mark.

[0046] (Embodiment 1) A semiconductor device according to one embodiment of the present invention will be described with reference to the drawings. 1 is a block diagram showing the configuration of a semiconductor device 10 included in the

[0047] Note that the configuration of the semiconductor device exemplified in this specification is an example and does not include all of the components. The semiconductor device does not need to have any necessary components among those shown in this specification. Furthermore, the device may have components other than those shown in this specification.

[0048] The semiconductor device 10 includes, for example, an antenna array 11, a transmission / reception control device 12, a signal processing Device 13, processor 14, GPU (Graphics Processing Unit) t)15, power control device 16, PLD (Programmable Logic Dev The transmission / reception control device 12 has a storage device 18 and a display device 19. is explained in detail in FIG.

[0049] 2 is a diagram illustrating the semiconductor device 10. The semiconductor device 10 is formed on a substrate. The layer L1 has a layer L2, a layer L3, and a layer L4. For example, the first transistor of the layer L1 has The transistor has a first semiconductor layer containing Si. The layer L3 has a second semiconductor layer containing Ga. The third transistor in the layer L3 The first to third semiconductor layers include at least one of In and Zn. The transistor is formed on or above a substrate comprising Si. This is a layer that does not have a semiconductor layer.

[0050] The first semiconductor layer of the first transistor is formed using the substrate. The second semiconductor layer of the transistor is formed using a crystal grown on the substrate. The third semiconductor layer of the third transistor is a first semiconductor layer and a second semiconductor layer. The semiconductor layer of the transistor is formed above the This is the layer in which the panel-forming region is formed.

[0051] The transmission / reception control device 12 includes a transmission / reception control device 12A and a transmission / reception control device 12B. The power supply control unit 16 includes a power supply control unit 16A and a power supply control unit 16B. For example, the layer L 1 includes a transmission / reception control device 12A, a signal processing device 13, a processor 14, a GPU 15, a power supply The layer L2 includes a control unit 16A and a PLD 17. The layer L2 includes a transmission / reception control unit 12B and a The layer L3 includes a storage device 18 and a display device 19. In addition, in FIG. 2, an antenna array 11 for wireless communication is formed on the layer L4. This shows:

[0052] The memory device 18 formed on the layer L3 includes a third transistor having a third semiconductor layer. However, the display device 19 may be formed of a third semiconductor different from the storage device 18. The third transistor may be formed with a layer L3. , layer L3A, and layer L3B on layer L3A. For example, storage device 18 may have The display device 19 can be formed of a transistor formed on the layer L3B. In other words, in the layer L3, the third The transistors can be stacked. Although an example in which transistors are stacked has been described, the third transistor to be stacked is The number of transistors is not limited.

[0053] 3 is a diagram illustrating the semiconductor device 10 in detail. The layer L1 includes a transmission / reception control device 12. A, signal processing unit 13, processor 14, GPU 15, power supply control unit 16A, and PL D17 is formed. In the layer L2, the transmission / reception control device 12B and the power supply control device 16B are formed. The layer L3A is formed with a memory device 18. The memory device 18 is a memory device 18A. The layer L3B has a display device 19 formed thereon. The display device 19 is a gate. Layer L4 has a display driver 19A and a display area 19B. A ray 11 is formed. The antenna array 11 has a plurality of antennas 11A.

[0054] The transmission / reception control device 12A formed on the layer L1 controls the signals transmitted and received via the antenna 11A. The transmission / reception control device 12B formed in the layer L2 has the function of processing the transmission / reception control. A transistor or a power supply having a capacity sufficient to supply the power used instantaneously by the control device 12A. has one of the diodes.

[0055] The signal processing device 13 provides a control signal to the gate driver 19A via the layer L3A, and Therefore, the signal processing device 13 can provide image data to the display area 19B. The signal processing device 13 can function as an image processing device. 5 can be used to perform expansion conversion of image data. Expansion conversion is the process of changing the filter of the displayed image. This includes filtering processing, pixel count conversion processing, etc.

[0056] The processor 14 controls the semiconductor device 10. The GPU 15 is a signal processing device. 13 and other artificial intelligence (AI) When performing learning or inference in e), some of the calculations can be processed at high speed. Therefore, in artificial intelligence inference, matrix operations using neural networks are often performed. The matrix calculation can be performed efficiently and quickly by using the GPU 15.

[0057] The power supply control device 16A formed on the layer L1 includes a transmission / reception control device 12, a signal processing device 13, To the processor 14, the GPU 15, the PLD 17, the storage device 18, or the display device 19 The power supply control device 16B formed on the layer L2 is a semiconductor A transistor or diode with sufficient power to supply the power used by device 10 The device has one of the following:

[0058] The PLD 17 can provide different functions by updating the logical configuration. The PLD 17 can function as a memory device. The previous display data displayed on the display device 19 is temporarily stored, and the previous display data and the transmission / reception control device are 12, it is possible to easily detect the difference between the received display data. The PLD 17 extends part of the arithmetic function of the signal processing unit 13 or the GPU 15. For example, the number of parallel operations can be increased when performing parallel calculations.

[0059] Next, the layer L2 will be described. The layer L2 is formed by growing a crystal on the substrate of the layer L1. Therefore, the first transistor formed using layer L1 is formed using layer L2. The second transistor is arranged so as not to overlap with the second transistor formed using the The second semiconductor layer of the transistor preferably contains Ga. The second semiconductor layer of the GaN layer preferably contains nitrogen or oxygen.

[0060] The layer L2 includes a transmission / reception control device 12B and a power supply control device 16B. 12B can supply a large amount of power that is used instantaneously by the transmission / reception control device 12A. The power supply control device 16B is connected to the transmission / reception control device 12A and the signal processing device 12B arranged on the layer L1. The power supply 13 supplies power to the processor 14, the GPU 15, the power control unit 16A, and the PLD 17. The power supply control device 16B also supplies power to the memory device 18 formed on the layer L3A, Power can be supplied to the display device 19 formed on layer L3B.

[0061] Next, the layer L3 will be described. First, the layer L3A formed on the layer L1 will be described. .

[0062] It is preferable that a storage device 18A is disposed on the transmission / reception control device 12A. It is preferable that a storage device 18B is disposed on the signal processing device 13. It is preferable that a storage device 18C is arranged on the GPU 14. It is preferable that a storage device 18F is provided on the power supply control device 16A. It is preferable that a storage device 18D is disposed on the PLD 17. It is preferable that

[0063] Any one of the storage devices 18A to 18F functions as a data saving register. As another example, any of the storage devices 18A to 18F may be a data management device. As another example, the memory devices 18A to 18C can function as a logical memory. One of the Fs is a FIFO memory (Fr) that can accommodate the different processing speeds of each device. It can function as a first in first out memory. For example, The data received by the transmission / reception control device 12 is temporarily stored in the FIFO memory, and the signal processing device The device 13 can use the processor 14 to read data from the FIFO memory. In this case, the transmission / reception control device 12 operates differently from the signal processing device 13 or the processor 14. The memory device 18E can operate at a frequency of 100 MHz. It is preferable that a plurality of pieces of information are stored.

[0064] The memory device 18 includes a third transistor. contains oxygen and further contains at least one or more of In, Ga, and Zn Therefore, the third semiconductor layer of the third transistor preferably contains an oxide semiconductor. In other words, the semiconductor layer in which the channel of the transistor is formed has a In the case of oxide semiconductors (Oxide Semiconductors), which are a type of metal oxide, A transistor containing S) is called an "OS transistor" or "OS-FET." OS transistors are known to have small variations in electrical characteristics due to temperature changes. In addition, since the energy gap of the semiconductor layer of an OS transistor is large, the channel width is 1 μm. Therefore, the off-state current characteristic can be extremely low, with a current value of several yA per 1000 sq.m. The OS transistor is preferably applied to a memory device. This will be explained in detail in the second embodiment.

[0065] Here, a memory device using an OS transistor will be described. When a transistor is used, the storage device can be called "OS memory."

[0066] The OS memory prevents data degradation even if power supply is stopped. Furthermore, the OS memory can be made smaller in size to hold data. This allows for storage devices suitable for high density. By utilizing the extremely low off-state current characteristics of transistors, Therefore, the OS memory can be used as a non-volatile memory. It can be considered a harpoon.

[0067] In addition, since OS memory is a method of writing charge to a node via an OS transistor, This eliminates the need for the high voltage required by conventional flash memory, enabling high-speed write operations. Charge injection and extraction into the floating gate or charge trapping layer can also be achieved. Therefore, the OS memory can be written and read virtually unlimited times. The OS memory is less susceptible to deterioration and is highly reliable compared to conventional flash memory. is obtained.

[0068] In addition, OS memory is a type of memory that operates at the atomic level, such as magnetic memory or resistive memory. There is no structural change. Therefore, OS memory is more efficient than magnetic memory and resistive memory. It has excellent rewrite durability.

[0069] Furthermore, the off-state current of OS transistors hardly increases even in high-temperature environments. The off-state current hardly increases even in temperatures above room temperature and below 200°C. The on-state current is less likely to decrease even under low temperature. By using OS transistors as transistors in semiconductor devices, A semiconductor device that operates stably even in a high temperature environment and has good reliability can be realized.

[0070] In addition, the OS transistor is used in the back end (BEOL) that forms the wiring of the semiconductor device. It can be formed by using a sputtering method during the process of One semiconductor device 10 can be formed using transistors with transistor characteristics. In other words, by using OS transistors, SoC (System on chip) ip) can be easily formed.

[0071] Note that the OS transistor may have a back gate. The back gate and the back gate are disposed so as to sandwich the channel forming region of the third semiconductor layer. The back gate can be made to function like a gate. Also, by changing the voltage of the back gate, By changing the back gate voltage, the threshold voltage of the transistor can be changed. The voltage may be the same as the gate voltage, or may be GND or any other voltage.

[0072] In addition, since the gate and back gate are generally formed of conductive layers, The function of preventing the electric field generated by the It has an electrostatic shielding function against static electricity. Fluctuations in the electrical characteristics of the transistor can be prevented.

[0073] Next, the layer L3B will be described. The display device 19 is configured by transistors included in the layer L3B. Although not described in detail in this specification, the display area 19B has a plurality of pixels. Each pixel has a light-emitting element. The light-emitting element may be an organic light-emitting device (OLED). nic Light Emitting Device) or LED (Light E It is preferable to use a mitting device.

[0074] Next, layer L4 will be described. The antenna array 11 has a plurality of antennas 11A. The antenna 11A is preferably formed of a light-transmitting conductive layer. The conductive layer may be made of indium oxide, ITO, indium zinc oxide, zinc oxide, or Gallium-doped zinc oxide or the like can be used.

[0075] FIG. 4 is a diagram illustrating a semiconductor device 10A having a different configuration from the semiconductor device 10 shown in FIG. In the configurations described below, the same parts or parts having similar functions will be referred to as the same. The same reference numerals are used in common among different drawings, and repeated explanations thereof will be omitted.

[0076] In the semiconductor device 10A, the layer L3B includes the display device 19, the memory device 18G, and the memory device 18. The semiconductor device 10 differs from the semiconductor device 10 in that it has a display device 19, a memory device 18G, and The third transistor included in the memory device 18H is formed in the same process.

[0077] 5 is a diagram illustrating the semiconductor device 10A in detail. The semiconductor device 10A includes a layer L3B 3 in that the semiconductor device 10 shown in FIG. Preferably, a storage device 18G is provided on the transmission / reception control device 12B. 18G stores setting information for the transmission / reception control device 12B. It is preferable that a storage device 18H is disposed on the upper side. The storage device 18H includes a power control device. The setting information of the storage device 16B is stored in the storage device 18G and the storage device 18H. Preferably, a memory is used.

[0078] FIG. 6A is a block diagram showing the configuration of a semiconductor device 10B, which is different from the semiconductor device 10 shown in FIG. The semiconductor device 10B shown in FIG. 6A includes a sensor module 20. 3 is a diagram illustrating a semiconductor device 10B having a different configuration from the semiconductor device 10 shown in FIG. The body device 10B has a layer L5 below the layer L1 (on the opposite side to the layer L2). The sensor module 20 is disposed on the substrate 10. The sensor module 20 is formed by a through-silicon via (TSV: Through Silicon Via) can be used to electrically connect to layer L1. The sensor module 20 can be an image sensor, an infrared sensor, an ultrasonic sensor, Alternatively, a touch sensor or the like can be used.

[0079] As an example, the case where the sensor module 20 is an image sensor will be described. The device 10B displays the information captured by the sensor module as an image on the display device 19. It can be shown.

[0080] The semiconductor device 10B is a device for wireless communication, signal processing for expanding and converting image data, a display device, and The sensor module can be configured as an SoC, reducing the number of components. Therefore, the semiconductor device 10B is required to be small and lightweight. The present invention is suitable for use in mobile terminals including goggle-type displays.

[0081] FIG. 7 is a diagram illustrating an example of the configuration of a wireless transceiver 900 as an example of the transmission / reception control device 12. The radio transceiver 900 includes a low noise amplifier (LNA) 901. amplifier), Band Pass Filter 902 (BPF: Band Pass Filter ter), mixer 903 (MIX: Mixer), band pass filter 904, demodulator 9 05 (DEM: Demodulator), Power Amplifier 911 (PA: Power A amplifier), bandpass filter 912, mixer 913, bandpass filter 9 14, Modulator 915 (MOD: Modulator), Duplexer 921 (DUP: Duplexer) exer), local oscillator 922 (LO: Local Oscillator), and It has antenna 931.

[0082] <Receive> A signal 941 transmitted from another semiconductor device or a base station or the like is input to an antenna 931 and The received signal is input to the low noise amplifier 901 via the duplexer 921. 1 has the function of transmitting and receiving wireless signals using a single antenna.

[0083] The low noise amplifier 901 converts a weak received signal into a signal strong enough to be processed by the radio transceiver 900. The signal 941 amplified by the low noise amplifier 901 is The signal is supplied to a mixer 903 via a filter 902 .

[0084] The bandpass filter 902 extracts the necessary frequency components from the frequency components contained in the signal 941. It has the function of attenuating frequency components outside a certain band and passing a required frequency band.

[0085] The mixer 903 mixes the signal 941 that has passed through the bandpass filter 902 with the signal 942 of the local oscillator 92. 2. The signal 943 generated by the superheterodyne method is mixed. The amplifier 903 mixes the signals 941 and 943 and outputs the difference frequency component and sum frequency component of the two signals. A signal having the following formula is fed to a bandpass filter 904:

[0086] The bandpass filter 904 has a function of passing one of the two frequency components. For example, the bandpass filter 904 passes the difference frequency component. The bandpass filter 904 also has the function of removing noise components generated in the mixer 903. The signal that has passed through is supplied to the demodulator 905. The demodulator 905 controls the supplied signal. The signal output from the demodulator 905 is converted into a digital signal or a data signal and output. The signal is provided to various processing units (arithmetic units, storage units, etc.).

[0087] <Send> The modulator 915 transmits control signals, data signals, etc. from the wireless transceiver 900 to other semiconductor devices. It also has the function of generating a basic signal to be transmitted to a base station, etc. The signal is supplied to the mixer 913 via a double-pass filter 914 .

[0088] The bandpass filter 914 filters out noise components that occur when the fundamental signal is generated by the modulator 915. It has the function of removing impurities.

[0089] The mixer 913 mixes the fundamental signal passed through the bandpass filter 914 with the local oscillator 922 The mixer has a function of mixing the signal 944 generated by the superheterodyne method. 913 mixes the fundamental signal with signal 944 and generates a signal with the difference frequency component and the sum frequency component of the two. The signal is fed to a bandpass filter 912 .

[0090] The bandpass filter 912 has a function of passing one of the two frequency components. For example, the bandpass filter 912 passes the sum frequency component. The bandpass filter 912 also has the function of removing noise components generated in the mixer 913. The signal that has passed through is supplied to a power amplifier 911.

[0091] The power amplifier 911 has a function of amplifying the supplied signal to generate a signal 942. The signal 942 is radiated to the outside from the antenna 931 via the duplexer 921 .

[0092] A wireless transceiver 900A, which is a modification of the wireless transceiver 900 described above, is shown in FIG. 8A and 8B. To reduce repetition of the explanation, the following mainly focuses on the wireless transceiver 900 and The differences will be explained below.

[0093] The wireless transceiver 900A has multiple antennas 931 to support the 5G communication standard. In addition, a plurality of duplexers 921, a plurality of low noise amplifiers 901, and a plurality of power amplifiers The radio transceiver 900A also includes a decoder circuit 906 (DEC) and It has a decoder circuit 916.

[0094] In FIG. 8A, an antenna 931, a duplexer 921, a low noise amplifier 901, and a power amplifier 8A shows a case where each antenna has five amplifiers 911. The first antenna 931 is designated as antenna 931[1], and the fifth antenna 931 is designated as antenna 931[5]. The duplexer 921, the low noise amplifier 901, and the power amplifier 911 are also The antenna 931, the duplexer 921, and the low noise amplifier 90 are written in the same way. The number of power amplifiers 911 and 912 is not limited to five.

[0095] The antenna 931[1] is electrically connected to the duplexer 921[1]. 1] is electrically connected to the low noise amplifier 901[1] and the power amplifier 911[1]. The antenna 931[5] is electrically connected to the duplexer 921[5]. 1[5] is electrically connected to the low noise amplifier 901[5] and the power amplifier 911[5]. The second to fourth antennas 931 are connected in the same manner as the antenna 931[1]. The second to fourth duplexers 921 are also electrically connected to the duplexer 921. 921 [1], the second to fourth low noise amplifiers 901 and the second to fourth power amplifiers It is electrically connected to the amplifier 911 .

[0096] The decoder circuit 906 is electrically connected to the plurality of low noise amplifiers 901. Five low noise amplifiers 901 are connected to the decoder circuit 906. The circuit 916 is electrically connected to a plurality of power amplifiers 911. In FIG. 8A, five power amplifiers are The power amplifier 911 is connected to a decoder circuit 916 .

[0097] The decoder circuit 906 includes low noise amplifiers 901[1] to 901[5]. The decoder circuit 906 has a function of selecting one or more of the following: The low-noise amplifier 901[1] to the low-noise amplifier 901[5] are sequentially selected. Similarly, the decoder circuit 916 outputs the power amplifiers 911[1] to 911[5]. The decoder circuit 916 has a function of selecting one or more of the following: The power amplifier 911 has a function of sequentially selecting the power amplifiers 911[1] to 911[5].

[0098] As an example, FIG. 8B shows a decoder circuit 906, a low noise amplifier 901[1], and a low noise amplifier 902. The decoder circuit 906 is connected to the low noise amplifier 901 [2]. [1] (hereinafter referred to as memory element 111[1]) and memory element 111 [1] is electrically connected via the terminal 124. Also, the decoder circuit 906 is the memory element 111 (memory element 111[2]) included in the low noise amplifier 901[2] ] is electrically connected to the memory element 111[2] via the terminal 124. Connected.

[0099] The memory element 111 includes a transistor 112 and a capacitor 113. The gate of transistor 112 is electrically connected to terminal 124. One of the drains of the transistor 112 is electrically connected to the terminal 123. The other drain is electrically connected to one electrode of the capacitor 113 and the gate of the transistor 115. The node 114 is connected to the other of the source and drain of the transistor 112. One of the electrodes of the capacitor 113 is formed on a wiring to which the gate of the transistor 115 is electrically connected. Terminal 124 is also connected to the source or drain of transistor 116 of decoder circuit 906. The transistor 112 is an OS transistor. The memory element 111 using an OS transistor is called an OS memory. It can be replaced.

[0100] The terminal 123 to which the memory element 111[1] is electrically connected and the terminal 123 to which the memory element 111[2] is electrically connected The terminal 123 for connecting electrically is electrically connected to the wiring 126. The voltage (charge) to be applied is supplied via a wiring 126 .

[0101] The decoder circuit 906 outputs a transformer to the terminal 124 electrically connected to any of the storage elements 111. It has the function of supplying a signal to turn on or off the resistor 112. The decoder circuit 906 sequentially outputs the memory elements 111 included in the low noise amplifier 901. By selecting the voltages, different voltages can be written to the nodes 114 for the storage elements 111. That is, a voltage suitable for each of the plurality of low noise amplifiers 901 is written to the node 114. It can be done.

[0102] The decoder circuit 916 also operates in the same manner as the decoder circuit 906 for the plurality of power amplifiers 911. It works.

[0103] The configurations, structures, methods, and the like shown in this embodiment may be used in conjunction with other embodiments and examples. The configuration, structure, method, etc. can be used in appropriate combination.

[0104] (Embodiment 2) In this embodiment, a transistor applicable to the semiconductor device described in the above embodiment will be described. As an example, a structure in which transistors having different electrical characteristics are stacked is described. This configuration will be described. By adopting this configuration, the degree of freedom in designing a semiconductor device can be increased. Furthermore, by stacking transistors with different electrical characteristics, The integration of the device can be increased.

[0105] A part of the cross-sectional structure of the semiconductor device is shown in FIG. 50, a transistor 500, a transistor 650, and a capacitor 600. 11A is a cross-sectional view of the transistor 500 in the channel length direction, and FIG. 11B is a cross-sectional view of the transistor 500 in the channel length direction. 11C is a cross-sectional view of the channel width direction of transistor 500, and FIG. 11D is a cross-sectional view of the channel width direction of transistor 550. For example, the transistor 500 is the same as the transistor shown in the above embodiment. Transistor 550 corresponds to transistor 116, and transistor 6 The capacitor 50 corresponds to the transistor 115. The capacitor 600 corresponds to the capacitor 113. The wirings 2001 to 2006 can be electrically connected to other transistors or the like. The wiring 2005 is electrically connected to a wiring 2006.

[0106] In this specification, the term "arranged in an overlapping position" is used to refer to a case where stacked transistors are arranged in an overlapping position. The range of a transistor may include a channel formation region of the transistor and The semiconductor layer of the transistor includes a region that functions as a source or a drain. do.

[0107] As an example, transistor 500 may be positioned so as to overlap transistor 550. In this case, as shown in FIG. 9, one of the source or drain regions of the transistor 500 is The portion is arranged at a position where one of the source and drain regions of the transistor 550 overlaps with the portion. In addition, one of the source and drain regions of the transistor 500 The portion is arranged at a position overlapping one of the source and drain of the transistor 550. It is possible.

[0108] In FIG. 9, for the sake of explanation, the transistor 500 is shown as a transistor 550 and a transistor 6 shows an example in which the transistors 650 are arranged at positions overlapping each other. Transistor 550 is a transistor included in layer L1, and transistor 650 is included in layer L2. The transistor 500 is a transistor included in the layer L3. It is a star.

[0109] The transistor 500 is an OS transistor. Therefore, the data voltage written to the storage node via the transistor 500 Alternatively, the charge can be retained for a long period of time. The frequency of operation is reduced, or refresh operation is not required, so the power consumption of the semiconductor device is reduced. can be reduced.

[0110] In FIG. 9, transistor 500 is provided above transistor 550, and capacitor 600 is It is provided above the transistor 550 and the transistor 500 .

[0111] The transistor 550 is provided on a substrate 311, and includes a conductor 316, an insulator 315, and a substrate A semiconductor region 313 consisting of a part of 311 functions as a source region or a drain region. It has a low resistance region 314a and a low resistance region 314b.

[0112] As shown in FIG. 11C, transistor 550 includes a top surface and a channel of semiconductor region 313. The side surfaces in the width direction of the transistor are covered with a conductor 316 via an insulator 315. By making the transistor 550 a fin type, the effective channel width increases, This can improve the on-state characteristics of the transistor 550. Since the supply of the current can be increased, the off characteristics of the transistor 550 can be improved. do.

[0113] The transistor 550 may be a p-channel transistor or an n-channel transistor. Either a transistor or a resistor may be used.

[0114] The region where the channel of the semiconductor region 313 is formed, the region in the vicinity thereof, the source region, or In the low resistance region 314a which becomes the drain region and the low resistance region 314b, silicon It preferably contains a semiconductor such as a silicon-based semiconductor, and it preferably contains single crystal silicon. Or Ge (germanium), SiGe (silicon germanium), GaAs (gallium It may be made of materials containing gallium aluminum arsenide (GaAlAs) or GaAlAs (Gallium Aluminum Arsenide). Silicon with effective mass controlled by applying stress to the crystal lattice and changing the lattice spacing. Alternatively, GaAs and GaAlAs may be used to form a transistor. The Star 550 is a HEMT (High Electron Mobility Transistor) stor) can also be used.

[0115] The low resistance region 314a and the low resistance region 314b are formed by the semiconductor layer applied to the semiconductor region 313. In addition to the conductive material, elements that impart n-type conductivity, such as arsenic and phosphorus, or p-type conductivity, such as boron, are added. It contains elements that impart electrical conductivity to the material.

[0116] The conductor 316, which functions as a gate electrode, is made of arsenic, phosphorus, or the like, which provides n-type conductivity. Semiconductor materials such as silicon that contain elements or elements that give them p-type conductivity, such as boron Conductive materials such as aluminum, metal, alloy, or metal oxide materials can be used. .

[0117] Since the work function is determined by the material of the conductor, it is necessary to select the material of the conductor. Specifically, the conductor is made of nitride silicon, and the threshold voltage of the transistor can be adjusted. It is preferable to use materials such as tantalum or tantalum nitride. To achieve this, metal materials such as tungsten and aluminum are used as layers for the conductor. It is preferable to use tungsten, in particular, in terms of heat resistance.

[0118] The transistor 550 is formed on a silicon on insulator (SOI) substrate. It may be formed using, for example.

[0119] In addition, for the SOI substrate, oxygen ions are implanted into a mirror-polished wafer, and then the wafer is heated to a high temperature. This allows an oxide layer to form at a certain depth from the surface, and also removes defects that have occurred in the surface layer. SIMOX (Separation by Implanted Oxygen) substrate and growth of microvoids formed by hydrogen ion implantation by heat treatment Smart Cut method, ELTRAN method (registered trademark: Epi SOI substrates formed by using techniques such as tactile layer transfer (TTL) are used. A transistor formed using a single crystal substrate may have a single crystal in the channel formation region. It has a semiconductor.

[0120] FIG. 10 illustrates a third transistor in layer L3A, transistor 550A, and a third transistor in layer L4A. 1 is a diagram illustrating a transistor 500 as a third transistor included in L3B. 10 shows an example in which the transistor 550A is electrically connected to the transistor 500. However, the transistor 550A is a transistor included in the memory device, and When the transistor 500 is a transistor included in a display device, the transistor 550A does not necessarily have to be connected to transistor 500.

[0121] 9, the transistor 500 shown in FIG. 10, or the transistor The resistor 550A is an example, and is not limited to this configuration. For example, a semiconductor device may be formed using only OS transistors. In the case of a circuit (meaning transistors of the same polarity, such as n-channel transistors only), In this case, as shown in FIG. 10, the configuration of the transistor 550A is changed to a similar configuration to that of the transistor 500. The transistor 500 will be described in detail later.

[0122] Here, the transistor 650 will be described. The transistor 650 is a transistor The transistor 650 is formed on the same substrate as the transistor 550. The semiconductor layer is formed on a silicon-on-insulator (SOI) substrate or an SOI substrate. It is preferable that the semiconductor layer has a crystal structure containing gallium. Examples include gallium nitride (GaN) and gallium oxide (GaOx).

[0123] A semiconductor device using GaN for the semiconductor layer 654 will be described with reference to FIG. GaN is grown by providing a low-temperature buffer layer 652 on the substrate 311 and single-crystallizing the low-temperature buffer layer 652. It can be formed by epitaxially growing GaN crystals. The single crystal GaN formed by this process corresponds to the semiconductor layer 654. An example using a crystalline silicon substrate is shown.

[0124] When forming the transistor 650, a semiconductor layer 656 is epitaxially grown on the semiconductor layer 654. It is preferable to use a semiconductor layer grown by a thermal process. The semiconductor layer 654 is preferably GaN. The semiconductor layer 656 is preferably AlGaN. For example, aluminum nitride (AlN) The band gap is approximately twice that of GaN (6.2 eV), and the electrostatic breakdown field is approximately four times that of GaN (12 MV / cm) and thermal conductivity approximately 1.5 times that of GaN (2.9W / cmK), making it an extremely excellent material. Therefore, AlN and mixed crystals of AlN and GaN are AlGaN is a preferred material for high-power, high-frequency devices. High Electron Mobility Transistor (HEMT) stor) can operate at higher voltages than HEMTs that use GaN as the channel formation region. At the interface between GaN and AlGaN, there is a polarization effect between GaN and AlGaN. This generates a two-dimensional electron gas (2DEG). In this case, the 2DEG serves as the channel formation region.

[0125] The conductor 330 is provided on the semiconductor layer 656. The conductor 330 is Equivalent to 50 source or drain.

[0126] The insulator 324 is sandwiched between the conductor 658 and the semiconductor layer 656. The conductor 658 is the gate electrode, and the insulator 324 is the gate insulator of the transistor 650. The insulator 324 may be silicon oxide, aluminum oxide, or hafnium oxide. For example, the insulator 324 may be made of silicon oxide, aluminum oxide, or the like. or hafnium oxide, etc., the off-state current of the transistor 650 Further, to explain the gate insulator in detail, the gate insulator is made of SiO2 It is preferable that the film is an Al2O3 film or an HfO2 film.

[0127] Also, the transistor 650 preferably has a recessed gate structure. Transistor 650 shows an example having a recessed gate structure. The transistor 650 has a recessed gate structure, which reduces the off-state current. The gate structure is formed by a semiconductor layer 656 overlapping with a gate electrode that forms a channel forming region. The semiconductor layer 656 is thinned by etching. The region of the semiconductor layer 656 that is exposed to the depletion enhancement of the 2DEG is called the recessed region. The non-recessed region also becomes larger due to the increased concentration of the 2DEG. A sufficient current can flow.

[0128] Over the transistor 550, the insulator 320, the insulator 322, the insulator 324, and the insulator The edge members 326 are stacked in order.

[0129] The insulators 320, 322, 324, and 326 may be, for example, an acid. silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, aluminum oxide, Aluminum oxynitride, aluminum nitride oxide, aluminum nitride, or the like may be used.

[0130] In this specification, silicon oxynitride refers to a material having a higher content of oxygen than nitrogen in its composition. Silicon nitride oxide refers to a material that contains more nitrogen than oxygen. In this specification, aluminum oxynitride refers to a material with a high content. Aluminum oxide nitride is a material that has a higher oxygen content than nitrogen. It refers to a material that contains more nitrogen than oxygen as a constituent.

[0131] The insulator 322 serves to eliminate a step caused by the transistor 550 and the like provided below. For example, the top surface of the insulator 322 may have a function as a planarizing film. To improve flatness, the surface is flattened by a planarization process using chemical mechanical polishing (CMP) or other methods. It may be possible.

[0132] The insulator 324 is also provided with a substrate 311 or a transistor 550 or the like. A film having a barrier property to prevent diffusion of hydrogen and impurities is formed in the area where the star 500 is provided. It is preferable to use

[0133] An example of a film having a barrier property against hydrogen is silicon nitride formed by CVD. Here, the transistor 500 or the like having an oxide semiconductor can be preferably used. When hydrogen diffuses into a semiconductor element, the characteristics of the semiconductor element may be deteriorated. Therefore, a structure for suppressing hydrogen diffusion between the transistor 500 and the transistor 550 is provided. Specifically, a film that suppresses the diffusion of hydrogen is preferably used. The film should have a low

[0134] The amount of hydrogen desorption can be analyzed using, for example, thermal desorption spectroscopy (TDS). For example, the amount of hydrogen desorbed from the insulator 324 can be determined by TDS analysis as follows: In the range of 50°C to 500°C, the amount of desorption converted to hydrogen atoms is Converted to a hit, it's 10 x 10 15 atoms / cm 2 Less than or equal to 5 x 10 15 a toms / cm 2 The following is fine.

[0135] It is preferable that the insulator 326 has a lower dielectric constant than the insulator 324. For example, The dielectric constant of the insulator 326 is preferably less than 4, more preferably less than 3. The relative dielectric constant of the insulator 326 is preferably 0.7 times or less than the relative dielectric constant of the insulator 324, and more preferably 0.6 times or less. By using a material with a low dielectric constant as the interlayer film, the parasitic capacitance generated between wirings can be reduced. It can be reduced.

[0136] In addition, the insulators 320, 322, 324, and 326 have capacitances of 60. 0, or the conductor 328 and the conductor 330 connected to the transistor 500 are embedded. The conductor 330 is connected to the source or drain electrode of the transistor 650. The conductor 328 and the conductor 330 function as plugs or wiring. In addition, the conductor that functions as a plug or wiring has a plurality of structures. In this specification and the like, the wiring and the wiring The wire and the plug to be connected may be an integral part. In other words, a part of the conductor may function as a wiring. In some cases, a part of the conductor functions as a plug.

[0137] The materials for each plug and wiring (conductor 328, conductor 330, etc.) include metal materials, Conductive materials such as alloy materials, metal nitride materials, or metal oxide materials can be used in single or multilayer configurations. High-temperature materials such as tungsten and molybdenum, which have both heat resistance and electrical conductivity, can be used. It is preferable to use a material with a melting point, and it is preferable to use tungsten. It is preferable to form the wiring board from a low-resistance conductive material such as aluminum or copper. This can reduce the wiring resistance.

[0138] A wiring layer may be provided on the insulator 326 and the conductor 330. For example, in FIG. An insulator 350, an insulator 352, and an insulator 354 are stacked in this order. A conductor 356 is formed on the insulators 350, 352, and 354. The conductor 356 is connected to a plug that connects to the transistor 550 and a plug that connects to the transistor 650. The conductor 356 functions as a plug or wiring. The conductive material 330 can be used to form the conductive material 330 .

[0139] For example, the insulator 350 has a barrier property against hydrogen, similar to the insulator 324. It is preferable to use an insulator having a barrier property against hydrogen. It is preferable that the insulating material 350 has a barrier property against hydrogen. A conductor having a barrier property against hydrogen is formed in the opening. The transistor 550 or the transistor 650 is a transistor 500 and a transistor 650 formed by a barrier layer. It can be separated from transistor 550 or transistor 650. This can suppress the diffusion of hydrogen into 00.

[0140] As a conductor having a barrier property against hydrogen, for example, tantalum nitride or the like is used. In addition, by laminating tantalum nitride and highly conductive tungsten, The diffusion of hydrogen from transistor 550 can be suppressed while maintaining the overall conductivity. In this case, the tantalum nitride layer having a barrier property against hydrogen is It is preferable that the insulating material 350 has a structure in which the insulating material 350 is in contact with the insulating material 350.

[0141] A wiring layer may be provided on the insulator 354 and the conductor 356. For example, in FIG. An insulator 360, an insulator 362, and an insulator 364 are stacked in this order. A conductor 366 is formed in the insulators 360, 362, and 364. The conductor 366 functions as a plug or wiring. The conductive material 328 and the conductive material 330 can be formed using the same materials.

[0142] For example, the insulator 360 has a barrier property against hydrogen, similar to the insulator 324. It is preferable to use an insulator having a barrier property against hydrogen. It is preferable that the insulating material 360 has a barrier property against hydrogen. A conductor having a barrier property against hydrogen is formed in the opening. The transistor 550 or the transistor 650 is a transistor 500 and a transistor 650 formed by a barrier layer. It can be separated from transistor 550 or transistor 650. This can suppress the diffusion of hydrogen into 00.

[0143] A wiring layer may be provided on the insulator 364 and the conductor 366. For example, in FIG. An insulator 370, an insulator 372, and an insulator 374 are stacked in this order. A conductor 376 is formed on the insulators 370, 372, and 374. The conductor 376 functions as a plug or wiring. The conductive material 328 and the conductive material 330 can be formed using the same materials.

[0144] For example, the insulator 370 has a barrier property against hydrogen, similar to the insulator 324. It is preferable to use an insulator having a barrier property against hydrogen. In particular, an insulator 370 having a barrier property against hydrogen is useful. A conductor having a barrier property against hydrogen is formed in the opening. The transistor 550 or the transistor 650 is a transistor 500 and a transistor 650 formed by a barrier layer. It can be separated from transistor 550 or transistor 650. This can suppress the diffusion of hydrogen into 00.

[0145] A wiring layer may be provided on the insulator 374 and the conductor 376. For example, in FIG. An insulator 380, an insulator 382, ​​and an insulator 384 are stacked in this order. A conductor 386 is formed on the insulators 380, 382, ​​and 384. The conductor 386 functions as a plug or wiring. The conductive material 328 and the conductive material 330 can be formed using the same materials.

[0146] For example, the insulator 380 has a barrier property against hydrogen, similar to the insulator 324. It is preferable to use an insulator having a barrier property against hydrogen. It is preferable that the insulator 380 has a barrier property against hydrogen. A conductor having a barrier property against hydrogen is formed in the opening. The transistor 550 or the transistor 650 is a transistor 500 and a transistor 650 formed by a barrier layer. It can be separated from transistor 550 or transistor 650. This can suppress the diffusion of hydrogen into 00.

[0147] In FIG. 14, transistor 550 is connected to transistor 650 via conductor 366. However, the example in which the transistor 550 is connected to the transistor 650 is shown. The wire is not limited to the conductor 366 .

[0148] In the above, the wiring layer including the conductor 356, the wiring layer including the conductor 366, the conductor 376 The wiring layer including the conductor 386 has been described. The semiconductor device is not limited to this. The number of layers may be three or less, or five or more wiring layers similar to the wiring layer including the conductor 356. That's fine.

[0149] On the insulator 384 are an insulator 510, an insulator 512, an insulator 514, and an insulator 516. are stacked in this order. It is preferable that the insulator 516 is made of a material that has a barrier property against oxygen and hydrogen. It's nice.

[0150] For example, the insulator 510 and the insulator 514 may include, for example, the substrate 311, the transistor The area where the transistor 550 is provided or the area where the transistor 650 is provided is A film with barrier properties that prevents hydrogen and impurities from diffusing is used in the region where 00 is provided. Therefore, the insulator 510 and the insulator 514 are preferably the same as the insulator 324. Materials can be used.

[0151] As an example of a film with barrier properties against hydrogen, silicon nitride formed by CVD is used. Here, a semiconductor element including an oxide semiconductor, such as the transistor 500, However, the diffusion of hydrogen may deteriorate the characteristics of the semiconductor element. The hydrogen diffusion occurs between the transistor 500 and the transistor 550 or the transistor 650. It is preferable to use a film that suppresses hydrogen diffusion. The film has a small amount of elemental detachment.

[0152] In addition, as a film having a barrier property against hydrogen, for example, an insulator 510 and an insulator 514 uses metal oxides such as aluminum oxide, hafnium oxide, and tantalum oxide. It is preferable that

[0153] In particular, aluminum oxide is highly resistant to oxygen and water, which can cause fluctuations in the electrical characteristics of transistors. It has a high blocking effect that prevents impurities such as oxygen and moisture from penetrating the membrane. Aluminum oxide is a material that can withstand hydrogen, moisture, and other chemicals during and after the transistor manufacturing process. This can prevent impurities from entering the transistor 500. This can suppress the release of oxygen from the oxide that makes up the transistor. It is suitable for use as a protective film for the substrate 500.

[0154] For example, the insulators 512 and 516 may be made of the same material as the insulator 320. In addition, materials with relatively low dielectric constants can be used as insulators. For example, the insulator 512 and the insulator 513 can reduce the parasitic capacitance between the wirings. The edge 516 may be a silicon oxide film, a silicon oxynitride film, or the like.

[0155] In addition, the insulators 510, 512, 514, and 516 are made of conductive materials. 518, and the conductors (for example, conductor 503) that constitute the transistor 500 are filled in. The conductor 518 is connected to the capacitor 600, the transistor 550, or the transistor The conductor 518 functions as a plug or wiring that connects to the resistor 650. The conductive material 328 and the conductive material 330 can be formed using the same materials.

[0156] In particular, the insulator 510 and the conductor 518 in the region in contact with the insulator 514 are oxidized to oxygen, hydrogen, and It is preferable that the conductive material has a barrier property against water. The transistor 550 or the transistor 650 is a transistor 500 and a compound semiconductor material containing oxygen, hydrogen, and and a layer having a barrier property against water, and the transistor 550 or The diffusion of hydrogen from the transistor 650 to the transistor 500 can be suppressed.

[0157] Above the insulator 516 is the transistor 500 .

[0158] As shown in FIGS. 11A and 11B, transistor 500 includes an insulator 514 and an insulator 516. A conductor 503 disposed so as to be embedded in an insulator 516, an insulator 516 and a conductor An insulator 520 disposed on the insulator 503, and an insulator 522 disposed on the insulator 520. , an insulator 524 disposed on the insulator 522, and an oxide layer disposed on the insulator 524. 530a, an oxide 530b disposed on the oxide 530a, and an oxide 530b disposed on the oxide 530b. Conductor 542a and conductor 542b are spaced apart from each other, and conductor 542a and conductor The conductive material 542a is disposed on the conductive material 542b, and an opening is formed between the conductive material 542a and the conductive material 542b so as to overlap the conductive material 542a. the insulator 580 disposed on the bottom and side of the opening, the insulator 545 disposed on the bottom and side of the opening, and the insulator 54 and a conductor 560 disposed on the forming surface of the 5.

[0159] 11A and 11B, the oxide 530a, the oxide 530b, the conductive The insulator 544 is disposed between the conductor 542a and the conductor 542b and the insulator 580. 11A and 11B, the conductor 560 is preferably made of an insulator 560. 45, and a conductor 560a provided inside the conductor 560a. 11A and 11B. As shown in FIG. 1, an insulator 574 is disposed on top of an insulator 580, a conductor 560, and an insulator 545. It is preferable to place

[0160] In this specification and the like, the oxide 530a and the oxide 530b are collectively referred to as oxides. The conductor 542a and the conductor 542b are collectively referred to as the conductor 530. Sometimes it's 42.

[0161] In the transistor 500, an oxide is formed in the region where the channel is formed and in the vicinity thereof. 5 shows a structure in which two layers of a carbide 530a and an oxide 530b are stacked. One embodiment of the present invention is not limited to this. For example, a single layer or three layers of oxide 530b may be used. The above-mentioned laminated structure may be provided.

[0162] In addition, although the conductor 560 in the transistor 500 has a two-layer structure, One embodiment of the present invention is not limited to this. For example, the conductor 560 may have a single layer structure. 9, 10, 11A, and 11B, or a laminated structure of three or more layers may be used. The transistor 500 shown in FIG. 14 is an example, and the circuit configuration and An appropriate transistor may be used depending on the driving method, etc.

[0163] Here, the conductor 560 functions as the gate electrode of the transistor, and the conductors 542a and and the conductor 542b function as a source electrode and a drain electrode, respectively. Thus, conductor 560 is inserted through the opening in insulator 580 and through conductors 542a and 542b. The conductor 560, the conductor 542a, and the conductor 542b are formed so as to be embedded in the region sandwiched between them. The placement of the conductor 542b is selected to be self-aligned with the opening of the insulator 580. In the transistor 500, the gate electrode is disposed between the source electrode and the drain electrode. Therefore, the conductor 560 can be arranged in a self-aligned manner without providing a margin for alignment. Since the transistor 500 can be formed without any gaps, the area occupied by the transistor 500 can be reduced. This allows for miniaturization and high integration of semiconductor devices.

[0164] Furthermore, the conductor 560 is self-aligned in the region between the conductors 542a and 542b. Since the conductor 560 is formed, the area where the conductor 560 overlaps with the conductor 542a or the conductor 542b is As a result, the conductor 560 does not have a gap between the conductor 542a and the conductor 542b. The parasitic capacitance formed can be reduced. This improves the scanning speed and provides high frequency characteristics.

[0165] Conductor 560 may function as a first gate (also called a top gate) electrode. The conductor 503 also functions as a second gate (also called a bottom gate) electrode. In this case, the voltage applied to the conductor 503 may be different from the voltage applied to the conductor 560. The threshold voltage of the transistor 500 is controlled by changing them independently without linking them together. In particular, applying a negative voltage to the conductor 503 turns on the transistor 5 It is possible to increase the threshold voltage of 00 and reduce the off-current. When a negative voltage is applied to the conductor 503, the voltage applied to the conductor 560 is larger than when no voltage is applied. The drain current can be reduced when the applied voltage is 0V.

[0166] The conductor 503 is arranged to overlap the oxide 530 and the conductor 560. When a voltage is applied to the conductor 560 and the conductor 503, a current is generated from the conductor 560. The electric field generated by the conductor 503 is connected to the electric field generated by the conductor 503, and the choke formed in the oxide 530 is generated. The channel forming area can be covered.

[0167] In this specification, a pair of gate electrodes (a first gate electrode and a second gate electrode) The structure of a transistor in which the channel formation region is electrically surrounded by the electric field of This is called a rounded channel (S-channel) configuration. In this case, the S-channel configuration is achieved by using a conductive layer that functions as the source and drain electrodes. The side and periphery of the oxide 530 in contact with the conductive body 542a and the conductive body 542b form a channel. The conductive material 542a and the conductive material 542b are I-shaped like the conductive material 542a. The side and periphery of the oxide 530 in contact with 542b are in contact with the insulator 544, so In this specification and the like, the I-type is defined as In addition, the S-chan disclosed in the present specification and the like can be treated as the same as high-purity genuine products. The nel configuration is different from the fin and planar configurations. By adopting this, the resistance to the short channel effect is improved. This makes it possible to provide a transistor in which this phenomenon is unlikely to occur.

[0168] The conductor 503 has the same structure as the conductor 518, and the insulator 514 and the insulator Conductor 503a is formed in contact with the inner wall of the opening of 516, and conductor 503b is formed further inside. In the transistor 500, the conductor 503a and the conductor 503b However, one embodiment of the present invention is not limited to this. For example, the conductor 503 may be a single layer or a laminated structure of three or more layers. stomach.

[0169] Here, the conductor 503a is a diffusion layer for impurities such as hydrogen atoms, hydrogen molecules, water molecules, and copper atoms. It is preferable to use a conductive material that has the function of suppressing the impurities (i.e., the impurities are less likely to permeate). Alternatively, the diffusion of oxygen (for example, at least one of oxygen atoms, oxygen molecules, etc.) can be suppressed. It is preferable to use a conductive material that has the function of preventing oxygen from permeating through the conductive material. In this specification, the function of suppressing the diffusion of impurities or oxygen means the function of suppressing the diffusion of the above impurities or oxygen. has the function of suppressing the diffusion of any one or all of the above oxygen.

[0170] For example, the conductor 503a has a function of suppressing the diffusion of oxygen, so that the conductor 503 This can prevent b from being oxidized and the electrical conductivity from decreasing.

[0171] When the conductor 503 also functions as a wiring, the conductor 503b is made of tungsten, copper, or the like. It is preferable to use a conductive material having high conductivity, such as aluminum or aluminum-based. In this embodiment, the conductor 503 is illustrated as a stack of conductors 503a and 503b. However, the conductor 503 may have a single layer structure.

[0172] The insulators 520, 522, and 524 function as a second gate insulating film. Possess the ability.

[0173] Here, the insulator 524 in contact with the oxide 530 has more oxygen than the stoichiometric composition. It is preferable to use an insulator containing a large amount of oxygen. The oxygen is released from the film by heating. In this specification and elsewhere, the oxygen released by heating is sometimes referred to as "excess oxygen." That is, the insulator 524 has a region containing excess oxygen (also called an "excess oxygen region"). It is preferable that the insulator containing such excess oxygen is formed in contact with the oxide 530. By providing the oxide 530, oxygen vacancies (V O :oxygen vacancy This can reduce the oxide film thickness (also referred to as oxide film thickness) and improve the reliability of the transistor 500. When hydrogen enters the oxygen vacancy in the oxide 530, the defect (hereinafter referred to as V O It may be called H ) can act as a donor, generating electrons as carriers. Some of them may combine with oxygen, which bonds with metal atoms, to generate electrons, which act as carriers. Therefore, a transistor using an oxide semiconductor containing a large amount of hydrogen is a normally-on transistor. In addition, hydrogen in oxide semiconductors tends to move due to stresses such as heat and electric fields. Therefore, if an oxide semiconductor contains a large amount of hydrogen, the reliability of the transistor will decrease. In one embodiment of the present invention, V in the oxide 530 O Reduce H as much as possible It is preferable to make it highly pure or substantially highly pure. O H is ten To obtain an oxide semiconductor with reduced impurities, it is necessary to remove impurities such as moisture and hydrogen from the oxide semiconductor. (also called "dehydration" or "dehydrogenation treatment") and supplying oxygen to the oxide semiconductor. It is important to compensate for the oxygen deficiency by adding oxygen to the surface (also called "oxygenation treatment"). O H etc. By using an oxide semiconductor in which the amount of impurities is sufficiently reduced for a channel formation region of a transistor, This makes it possible to impart stable electrical properties.

[0174] As an insulator having an excess oxygen region, specifically, an oxide in which a part of oxygen is released by heating is used. It is preferable to use oxide materials. Oxides that release oxygen when heated are called TDS (Th Thermal Desorption Spectroscopy (DSS) analysis revealed that the oxygen atoms The converted amount of oxygen desorption is 1.0 x 10 18 atoms / cm 3 or more, preferably 1.0 x10 19 atoms / cm 3 More preferably, 2.0 × 10 19 atoms / c m 3 or more, or 3.0 x 10 20 atoms / cm 3 The oxide film is as described above. The surface temperature of the film during the TDS analysis is 100°C or higher and 700°C or lower, or The temperature is preferably in the range of 00°C or higher and 400°C or lower.

[0175] In addition, the insulator having the excess oxygen region and the oxide 530 are brought into contact with each other and subjected to heat treatment. One or more of microwave treatment and RF treatment may be performed. By performing this, water or hydrogen in the oxide 530 can be removed. At 530, a reaction occurs in which the VoH bond is broken, in other words, "V O H→Vo+ The reaction "H" occurs, and some of the hydrogen generated at this time is It combines with oxygen to form H2O, which is then removed from the oxide 530 or the insulators adjacent to the oxide 530. In addition, some of the hydrogen may be gettered to the conductor 542. .

[0176] The microwave treatment may be carried out using, for example, an apparatus having a power source that generates high-density plasma. Alternatively, it is preferable to use a device having a power source that applies RF to the substrate side. By using a gas containing oxygen and high density plasma, high density oxygen radicals are generated. By applying RF to the substrate side, the high density plasma generated 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 200 The microwave treatment may be performed at a pressure of 400 Pa or more, more preferably 400 Pa or more. The gases introduced into the device are, for example, oxygen and argon, with an oxygen flow rate ratio (O / (O2+Ar)) is set to 50% or less, preferably 10% or more and 30% or less.

[0177] In addition, during the manufacturing process of the transistor 500, the surface of the oxide 530 is exposed. The heat treatment is preferably carried out at a temperature of, for example, 100° C. or higher and 450° C. or lower. The heat treatment is preferably performed at a temperature of 350° C. or higher and 400° C. or lower. Or in an inert gas atmosphere, or oxidizing gas is 10 ppm or more, 1% or more, or For example, it is preferable to carry out the heat treatment in an oxygen atmosphere. This supplies oxygen to the oxide 530, and oxygen vacancies (V O) can be reduced. The heat treatment may be carried out under reduced pressure. Alternatively, the heat treatment may be carried out under nitrogen gas or nitrogen gas. After heat treatment in an active gas atmosphere, oxidizing gas was added at 10p to compensate for the oxygen that was released. The treatment may be carried out in an atmosphere containing at least pm, at least 1%, or at least 10% of an oxidizing gas. After heat treatment in an atmosphere containing 10 ppm or more, 1% or more, or 10% or more, Alternatively, the heat treatment may be performed in a nitrogen gas or inert gas atmosphere.

[0178] In addition, by performing an oxygen addition treatment on the oxide 530, oxygen vacancies in the oxide 530 are filled with oxygen. In other words, it promotes the reaction "Vo + O → null" Furthermore, the supplied oxygen reacts with the hydrogen remaining in the oxide 530. This allows the hydrogen to be removed as H2O (dehydration). The hydrogen remaining in the substance 530 recombines with the oxygen vacancy to form V. O inhibits the formation of H It is possible.

[0179] Also, if the insulator 524 has an excess oxygen region, the insulator 522 may be oxygen-rich (e.g., It has the function of suppressing the diffusion of oxygen atoms, oxygen molecules, etc. (the oxygen is less likely to permeate) It is preferable that:

[0180] The insulator 522 has a function of suppressing the diffusion of oxygen and impurities, and the oxide 530 The oxygen contained in the conductor 503 is preferably not diffused to the insulator 520 side. This can prevent the insulator 524 and the oxide 530 from reacting with oxygen.

[0181] The insulator 522 may be, for example, aluminum oxide, hafnium oxide, aluminum and hafnium oxide. Oxides containing hafnium (hafnium aluminate), tantalum oxide, zirconium oxide, Lead zirconate titanate (PZT), strontium titanate (SrTiO3), or ( Insulators containing so-called high-k materials such as Ba,Sr)TiO3 (BST) are deposited in a single layer or As transistors become smaller and more highly integrated, Thinning the gate insulating film can cause problems such as leakage current. By using a high-k material as an insulator that functions as a transistor, the physical thickness can be maintained. This makes it possible to reduce the gate voltage during transistor operation.

[0182] In particular, it has the function of suppressing the diffusion of impurities and oxygen (the oxygen is less likely to permeate). a) Insulators containing oxides of one or both of aluminum and hafnium, which are insulating materials It is recommended to use an insulator containing oxides of either or both aluminum and hafnium. Aluminum oxide, hafnium oxide, oxides containing aluminum and hafnium ( It is preferable to use materials such as hafnium aluminate. When the insulator 522 is formed, the insulator 522 prevents oxygen from being released from the oxide 530 and prevents the transistor from being damaged. This layer functions as a layer that suppresses the intrusion of impurities such as hydrogen from the periphery of the capacitor 500 into the oxide 530. do.

[0183] Alternatively, for example, aluminum oxide, bismuth oxide, germanium oxide, or the like may be added to these insulators. um, niobium oxide, silicon oxide, titanium oxide, tungsten oxide, yttrium oxide, Zirconium oxide may be added, or these insulators may be nitrided. Silicon oxide, silicon oxynitride or silicon nitride may be laminated on the insulator. .

[0184] The insulator 520 is preferably thermally stable. For example, silicon oxide and Silicon oxide nitride and silicon oxynitride are suitable because they are thermally stable. By combining this insulator with silicon oxide or silicon oxynitride, Furthermore, it is possible to obtain an insulator 520 having a laminated structure with a high relative dielectric constant.

[0185] 11A and 11B, the transistor 500 has a three-layer stack structure. As the second gate insulating film, an insulator 520, an insulator 522, and an insulator 524 are illustrated. However, the second gate insulating film may have a single layer, two layers, or a laminated structure of four or more layers. In this case, the laminated structure is not limited to the same material, but may be a laminated structure made of different materials. It can also be composed of

[0186] The transistor 500 includes an oxide 530 including a channel formation region, and an oxide semiconductor The oxide semiconductor is made of at least one of In and Zn. For example, the oxide 530 may contain In-M-Zn oxide (element M is aluminum, gallium, yttrium, copper, vanadium, beryllium, boron, Titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium , neodymium, hafnium, tantalum, tungsten, magnesium, etc. It is preferable to use a metal oxide such as one or more metal oxides.

[0187] The metal oxide that functions as an oxide semiconductor may be formed by a sputtering method. Alternatively, the deposition may be performed by ALD (Atomic Layer Deposition). Note that a metal oxide functioning as an oxide semiconductor will be described in detail in other embodiments. do.

[0188] In addition, the metal oxide that functions as a channel forming region in the oxide 530 has a band It is preferable to use a material with a gap of 2 eV or more, preferably 2.5 eV or more. As shown in Fig. 1, by using a metal oxide with a wide band gap, the off-state current of a transistor can be reduced. can be reduced.

[0189] The oxide 530 has an oxide 530a under the oxide 530b, so that the oxide 530a The diffusion of impurities from the structure formed below the oxide 530b can be suppressed. can.

[0190] The oxide 530 has a structure of a plurality of oxide layers with different atomic ratios of each metal atom. Specifically, it is preferable that the metal oxide used for the oxide 530a has a content of 0.01% or less among the constituent elements. The atomic ratio of element M is the atomic ratio of element M in the constituent elements of the metal oxide used for oxide 530b. It is preferable that the atomic ratio of M is larger than that of M. In addition, the metal oxide used for the oxide 530a is In the metal oxide used for the oxide 530b, the atomic ratio of the element M to In is It is preferable that the atomic ratio of element M to In is larger than that of element M. In the metal oxide used in the oxide 530a, the atomic ratio of In to element M is It is preferable that the atomic ratio of In to M in the metal oxide is larger than that of In.

[0191] In addition, the energy of the conduction band minimum of the oxide 530a is greater than the energy of the conduction band minimum of the oxide 530b. In other words, the electron affinity of the oxide 530a is preferably higher than the electron affinity of the oxide 530a. is preferably smaller than the electron affinity of oxide 530b.

[0192] Here, at the junction between the oxide 530a and the oxide 530b, the energy of the bottom of the conduction band is In other words, the junction of oxide 530a and oxide 530b The energy level of the conduction band minimum at the junction changes continuously or is called a continuous junction. To achieve this, the oxide 530a and the oxide 530b are This is advantageous in that the defect level density of the mixed layer formed by this method is reduced.

[0193] Specifically, the oxide 530a and the oxide 530b have a common element other than oxygen (mainly By using the oxide as a component, it is possible to form a mixed layer with a low defect level density. When the material 530b is an In-Ga-Zn oxide, the oxide 530a is an In-Ga-Zn It is preferable to use oxide, Ga-Zn oxide, gallium oxide, etc.

[0194] At this time, the main path of the carriers is the oxide 530b. By forming the oxide 530a and the oxide 530b in this manner, the defect state density at the interface between the oxide 530a and the oxide 530b is reduced. Therefore, the influence of interface scattering on carrier conduction is reduced, and The transistor 500 can obtain a high on-state current.

[0195] On the oxide 530b, a conductor 542 is formed, which functions as a source electrode and a drain electrode. The conductors 542a and 542b are provided as follows: are aluminum, chromium, copper, silver, gold, platinum, tantalum, nickel, titanium, molybdenum Niobium, tungsten, hafnium, vanadium, niobium, manganese, magnesium, zirconium Strontium, Beryllium, Indium, Ruthenium, Iridium, Strontium, Lanthanum or an alloy containing the above metal element as a component, or the above metal element It is preferable to use an alloy in which the above-mentioned materials are combined. For example, tantalum nitride, titanium nitride, tantalum tungsten, nitrides containing titanium and aluminum, nitrides containing tantalum and aluminum , ruthenium oxide, ruthenium nitride, oxides containing strontium and ruthenium, lanthanum It is preferable to use oxides containing tantalum and nickel. titanium and aluminum nitrides, tantalum and aluminum nitrides, and titanium oxides Ruthenium, ruthenium nitride, oxides containing strontium and ruthenium, lanthanum and nickel Oxides containing chlorine are conductive materials that are resistant to oxidation, or that maintain conductivity even when they absorb oxygen. Furthermore, metal nitride films such as tantalum nitride are preferred because they are materials that can withstand hydrogen or It is preferable because it has a barrier property against oxygen.

[0196] In addition, although the conductor 542a and the conductor 542b are shown as having a single layer structure in FIG. Alternatively, a laminated structure of two or more layers may be used. For example, a tantalum nitride film and a tungsten film may be laminated. Alternatively, a titanium film and an aluminum film may be stacked. Two-layer structure with an aluminum film laminated on a copper-magnesium-aluminum alloy film, and a copper film on a copper-magnesium-aluminum alloy film Two-layer structure with a copper film on a titanium film, two-layer structure with a copper film on a tungsten film A two-layer structure may also be used.

[0197] Also, a titanium film or titanium nitride film and an aluminum film overlaid on the titanium film or titanium nitride film are used. An aluminum film or a copper film is laminated, and a titanium film or a titanium nitride film is further formed thereon. A three-layer structure consisting of a molybdenum film or molybdenum nitride film and a molybdenum film or molybdenum nitride film. An aluminum or copper film is layered on top of the molybdenum film, and then a molybdenum or In addition, there are three-layer structures in which indium oxide, tin oxide or molybdenum nitride is formed. Alternatively, a transparent conductive material containing zinc oxide may be used.

[0198] As shown in FIG. 11A, 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 may be used as either a source region or a drain region. The region 543b functions as the other of the source region and the drain region. A channel forming region is formed in the region sandwiched between the region 543a and the region 543b.

[0199] 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 density in the region 543a (region 543b) increases, and the region 543a (region 543b) becomes a low resistance region. become.

[0200] The insulator 544 is provided to cover the conductor 542a and the conductor 542b. The insulator 544 prevents oxidation of the conductive material 542a and the conductive material 542b. It may be provided to cover the side of object 530 and to be in contact with insulator 524.

[0201] Insulator 544 includes hafnium, aluminum, gallium, yttrium, and zirconium. Smoke, tungsten, titanium, tantalum, nickel, germanium, neodymium, lanthanum Alternatively, a metal oxide containing one or more selected from magnesium, etc. may be used. The insulator 544 may be made of silicon oxynitride or silicon nitride. It can also be used.

[0202] In particular, the insulator 544 may be an oxide of aluminum or hafnium or both. Insulators containing aluminum oxide, hafnium oxide, aluminum, and hafnium It is preferable to use oxides containing hafnium (hafnium aluminate). Hafnium aluminate has higher heat resistance than hafnium oxide film. This is preferable because it is difficult to crystallize during heat treatment at room temperature. The body 542b is made of a material that is resistant to oxidation or that does not significantly decrease in conductivity even when it absorbs oxygen. In this case, the insulator 544 is not an essential component. Just calculate it.

[0203] By including the insulator 544, impurities such as water and hydrogen contained in the insulator 580 can be removed. Diffusion into the oxide 530b can be suppressed via the insulator 545. The excess oxygen contained in the insulator 580 can prevent the conductor 560 from being oxidized. do.

[0204] The insulator 545 functions as a first gate insulating film. Similar to the body 524, an insulator containing excess oxygen and releasing oxygen when heated is used. It is preferable to form

[0205] Specifically, silicon oxide having excess oxygen, silicon oxynitride, silicon nitride oxide, Silicon nitride, fluorine-doped silicon oxide, carbon-doped silicon oxide, carbon, and Silicon oxide doped with nitrogen and silicon oxide having vacancies can be used. In particular, silicon oxide and silicon oxynitride are preferred because they are stable to heat.

[0206] By providing an insulator containing excess oxygen as the insulator 545, oxygen can be removed from the insulator 545. Oxygen can be effectively supplied to the channel forming region of the oxide 530b. As with 524, the concentration of impurities such as water or hydrogen in the insulator 545 is reduced. The thickness of the insulator 545 is preferably 1 nm or more and 20 nm or less.

[0207] In addition, in order to efficiently supply excess oxygen contained in the insulator 545 to the oxide 530, A metal oxide may be provided between the insulating layer 545 and the conductor 560. It is preferable to suppress the diffusion of oxygen from the body 545 to the conductor 560. By providing a metal oxide, the diffusion of excess oxygen from the insulator 545 to the conductor 560 is suppressed. In other words, it is possible to suppress the decrease in the amount of excess oxygen supplied to the oxide 530. In addition, oxidation of the conductor 560 due to excess oxygen can be suppressed. Any material that can be used for the insulator 544 may be used.

[0208] Note that the insulator 545 may have a stacked structure similar to the second gate insulating film. As transistors become smaller and more highly integrated, the gate insulating film becomes thinner, which reduces leakage current and other problems. Therefore, the insulator that functions as the gate insulating film should be high-k By using a laminated structure of a material that is thermally stable, the thickness of the material can be maintained while maintaining the thickness of the material. This allows for a reduction in the gate voltage during transistor operation. A simple laminated structure can be achieved.

[0209] The conductor 560 that functions as the first gate electrode has a two-layer structure in FIGS. 11A and 11B. However, it may have a single layer structure or a laminated structure of three or more layers.

[0210] The conductor 560a is a hydrogen atom, a hydrogen molecule, a water molecule, a nitrogen atom, a nitrogen molecule, or a nitrogen oxide molecule. (N2O, NO, NO2, etc.), conductive material with the function of suppressing the diffusion of impurities such as copper atoms It is preferable to use a material containing a small amount of oxygen (for example, oxygen atoms, oxygen molecules, etc.). It is preferable to use a conductive material that has the function of suppressing the diffusion of at least one of the conductors. Since 60a has the function of suppressing the diffusion of oxygen, the oxygen contained in the insulator 545 This can prevent the conductor 560b from being oxidized and the conductivity from decreasing. Examples of conductive materials that have the function of suppressing scattering include tantalum, tantalum nitride, and tantalum fluoride. It is preferable to use ruthenium oxide or ruthenium oxide as the conductor 560a. Therefore, an oxide semiconductor that can be used for the oxide 530 can be used. By forming the conductive material 60b by sputtering, the electrical resistance value of the conductive material 560a is reduced. It can be made into a conductor. This is called an OC (Oxide Conductor) electrode. It is possible.

[0211] The conductor 560b is a conductive material mainly composed of tungsten, copper, or aluminum. In addition, since the conductor 560b also functions as a wiring, It is preferable to use a conductor with high conductivity, such as tungsten, copper, or aluminum. The conductor 560b can be made of a conductive material containing aluminum as a main component. For example, a laminated structure of titanium or titanium nitride and the above conductive material may be used. good.

[0212] The insulator 580 is disposed on the conductor 542a and the conductor 542b via the insulator 544. The insulator 580 preferably has an excess oxygen region. 80 includes silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, and fluorine. Nitrogen-doped silicon oxide, carbon-doped silicon oxide, carbon- and nitrogen-doped silicon oxide It is preferable that the material be silicon oxide, silicon oxide having pores, or resin. Silicon oxide and silicon oxynitride are particularly preferred because they are thermally stable. Silicon oxide and silicon oxide with vacancies easily form excess oxygen regions in later processes. This is preferable because it can

[0213] The insulator 580 preferably has an excess oxygen region. Oxygen is released upon heating. By providing the insulator 580, oxygen in the insulator 580 can be efficiently supplied to the oxide 530. It should be noted that the concentration of impurities such as water or hydrogen in the insulator 580 is reduced. It is preferable that

[0214] The opening in the insulator 580 is formed to overlap the region between the conductor 542a and the conductor 542b. As a result, the conductor 560 is connected to the opening of the insulator 580 and the conductor 542a. It is formed so as to be embedded in the region sandwiched between the bodies 542b.

[0215] In miniaturizing semiconductor devices, it is required to shorten the gate length. It is necessary to prevent the conductivity of the conductor 60 from decreasing. In this embodiment, the conductor 560 may have a shape with a high aspect ratio. The conductor 560 is provided so as to be embedded in the opening of the insulator 580. Even a shape with a high ratio can be formed without causing the conductor 560 to collapse during the process. Cut.

[0216] The insulator 574 is disposed on the top surface of the insulator 580, the top surface of the conductor 560, and the top surface of the insulator 545. The insulator 574 is preferably provided in contact with the surface. Thus, an excess oxygen region can be provided in the insulator 545 and the insulator 580. This allows oxygen to be supplied into the oxide 530 from the excess oxygen region.

[0217] For example, the insulator 574 may be hafnium, aluminum, gallium, yttrium, Zirconium, tungsten, titanium, tantalum, nickel, germanium, or magnesium It is possible to use a metal oxide containing one or more metals selected from the group consisting of cadmium, cadmium, and sulphur. Cut.

[0218] In particular, aluminum oxide has a high barrier property and is a thin film of 0.5 nm to 3.0 nm. Therefore, the diffusion of hydrogen and nitrogen can be suppressed even if sputtering is performed. The aluminum oxide film formed by this method is a source of oxygen and also a barrier for impurities such as hydrogen. It can also function as a film.

[0219] In addition, it is preferable to provide an insulator 581 that functions as an interlayer film over the insulator 574. The insulator 581, like the insulator 524, has a low impurity concentration such as water or hydrogen in the film. is preferably reduced.

[0220] Also, the insulating material 581, the insulating material 574, the insulating material 580, and the insulating material 544 are formed. The conductor 540a and the conductor 540b are disposed in the opening. The conductor 540a and the conductor 540b are provided opposite each other with the conductor 560 in between. 0b has the same configuration as conductor 546 and conductor 548, which will be described later.

[0221] An insulator 582 is provided on the insulator 581. The insulator 582 is resistant to oxygen and hydrogen. Therefore, the insulator 582 is preferably made of an insulating material. The insulator 582 may be made of the same material as the insulator 514. For example, aluminum oxide may be used. It is preferable to use metal oxides such as tungsten oxide, hafnium oxide, and tantalum oxide.

[0222] In particular, aluminum oxide is highly resistant to oxygen and water, which can cause fluctuations in the electrical characteristics of transistors. It has a high blocking effect that prevents impurities such as oxygen and moisture from penetrating the membrane. Aluminum oxide is a material that can withstand hydrogen, moisture, and other chemicals during and after the transistor manufacturing process. This can prevent impurities from entering the transistor 500. This can suppress the release of oxygen from the oxide that makes up the transistor. It is suitable for use as a protective film for the substrate 500.

[0223] An insulator 586 is provided on the insulator 582. The insulator 586 is The same materials as those of 320 can be used. In addition, these insulators have a relatively low dielectric constant. By using a material with high insulating properties, the parasitic capacitance between wiring can be reduced. The edge 586 can be a silicon oxide film, a silicon oxynitride film, or the like.

[0224] Also, the insulator 520, the insulator 522, the insulator 524, the insulator 544, the insulator 580, the insulator The insulator 574, the insulator 581, the insulator 582, and the insulator 586 are provided with the conductor 546 and and a conductor 548 and the like are embedded therein.

[0225] The conductor 546 and the conductor 548 are connected to the capacitor 600, the transistor 500, or the transistor The conductor 546 has a function as a plug or wiring that connects to the transistor 550. The conductor 548 may be formed using the same material as the conductor 328 and the conductor 330. This can be done.

[0226] After the transistor 500 is formed, an opening is formed to surround the transistor 500. An insulator having high barrier properties against hydrogen or water may be formed so as to cover the opening. By encasing the transistor 500 in the insulator with high barrier properties, moisture, In addition, it is possible to prevent hydrogen from penetrating the transistors 500. The whole may be wrapped in an insulator that has high barrier properties against hydrogen or water. When forming an opening to surround the transistor 500, for example, the insulator 522 or the insulator An opening is formed that reaches the insulator 514, and the above-mentioned barrier is placed in contact with the insulator 522 or the insulator 514. If a highly flexible insulator is formed, the manufacturing process of the transistor 500 can be performed simultaneously. In addition, examples of insulators with high barrier properties against hydrogen or water include A material similar to that of the insulator 522 or the insulator 514 may be used.

[0227] Next, a capacitor 600 is provided above the transistor 500. The capacitor 600 is , a conductor 610, a conductor 620, and an insulator 630.

[0228] Furthermore, a conductor 612 may be provided over the conductor 546 and the conductor 548. 612 has a function as a plug or wiring that connects to the transistor 500. The conductor 610 functions as an electrode of the capacitor 600. The conductive body 610 can be formed in the same process.

[0229] Conductor 612 and conductor 610 may be made of molybdenum, titanium, tantalum, tungsten, or the like. Metal film containing elements selected from the group consisting of silicon, aluminum, copper, chromium, neodymium, and scandium or a metal nitride film containing the above-mentioned elements (tantalum nitride film, titanium nitride film, nitride Molybdenum film, tungsten nitride film, etc. can be used. oxides containing tungsten oxide, indium zinc oxides containing tungsten oxide Lead oxide, indium oxide with titanium oxide, indium tin oxide with titanium oxide, Conductive materials such as indium zinc oxide and indium tin oxide doped with silicon oxide It can also be applied.

[0230] In this embodiment, the conductor 612 and the conductor 610 are shown as having a single-layer structure. For example, a conductive material having a barrier property and a conductive material having a barrier property may be used. Conductors with barrier properties and highly conductive conductors A highly adhesive conductor may be formed.

[0231] The conductor 620 is provided so as to overlap with the conductor 610 with the insulator 630 interposed therebetween. The conductor 620 is made of a conductive material such as a metal material, an alloy material, or a metal oxide material. High-melting-point materials such as tungsten and molybdenum, which are both heat-resistant and conductive, are used. It is preferable to use tungsten, and it is particularly preferable to use tungsten. When forming the same structure as other components, low-resistance metal materials such as Cu (copper) and Al (aluminum) are used. Minium) or the like can be used.

[0232] An insulator 640 is provided on the conductor 620 and the insulator 630. The insulator 40 can be made of the same material as the insulator 320. , and may function as a planarizing film that covers the underlying unevenness.

[0233] By using this structure, a semiconductor device including a transistor having an oxide semiconductor This allows for miniaturization or high integration.

[0234] Examples of a substrate that can be used for a semiconductor device according to one embodiment of the present invention include a glass substrate, a quartz substrate, and the like. Plate, sapphire substrate, ceramic substrate, metal substrate (e.g., stainless steel substrate, Substrate with stainless steel foil, tungsten substrate, tungsten foil semiconductor substrates (e.g., single crystal semiconductor substrates, polycrystalline semiconductor substrates, or SOI (Silicon on Insulator) substrate In addition, a plate having heat resistance capable of withstanding the processing temperature of this embodiment can be used. A plastic substrate may be used. An example of a glass substrate is barium borosilicate glass. Glass, aluminosilicate glass, or aluminoborosilicate glass, or soda glass Other examples include glass-ceramics.

[0235] Alternatively, the substrate may be a flexible substrate, a laminated film, a paper containing a fibrous material, or A flexible substrate, a laminated film, a base film, etc. can be used. Examples of films include polyethylene terephthalate. Polyethylene naphthalate (PET), Polyethersulfone (PES) ), and polytetrafluoroethylene (PTFE) are typical plastics. For example, synthetic resin such as acrylic resin is used. Examples include polyethylene, polyester, polyvinyl fluoride, and polyvinyl chloride. Examples include polyamide, polyimide, aramid resin, epoxy resin, and inorganic vapor deposition film. In particular, semiconductor substrates, single crystal substrates, SOI substrates, etc. By manufacturing transistors using this method, variations in characteristics, size, and shape are reduced. This allows the manufacture of small-sized transistors with high current capacity. By constructing a circuit using such transistors, it is possible to reduce the power consumption of the circuit or to increase the integration density of the circuit. This can be achieved.

[0236] In addition, a flexible substrate is used as the substrate, and transistors, resistors, and Alternatively, a substrate and a transistor, a resistor, and a capacitor may be formed. A release layer may be provided between the capacitor and the like. Or, after the whole process is completed, it can be separated from the substrate and used for transferring to another substrate. In this case, transistors, resistors, and / or capacitors are mounted on substrates with poor heat resistance or flexible materials. The above-mentioned peeling layer may be formed of, for example, a tungsten film and a silicon oxide film. The structure is a laminated structure of an inorganic film with an inorganic film, or a structure in which an organic resin film such as polyimide is formed on a substrate. A silicon film containing hydrogen or the like can be used.

[0237] That is, a semiconductor device is formed on a substrate, and then the semiconductor device is transferred to another substrate. An example of the substrate onto which the semiconductor device is transferred is a substrate on which the above-described transistor is formed. In addition to the substrates that can be used, paper substrates, cellophane substrates, aramid film substrates, polyimide Film substrate, stone substrate, wood substrate, fabric substrate (natural fibers (silk, cotton, linen), synthetic fibers (nylon) lon, polyurethane, polyester) or regenerated fiber (acetate, cupra, rayon These include recycled polyester, leather substrates, and rubber substrates. By using the substrate, it is possible to manufacture flexible semiconductor devices and unbreakable semiconductor devices. It is possible to improve the structure, provide heat resistance, and reduce the weight or thickness.

[0238] By providing a semiconductor device on a flexible substrate, an increase in weight can be suppressed and the semiconductor device is less likely to be damaged. Therefore, a semiconductor device can be provided.

[0239] <Transistor variation 1> The transistor 500A shown in FIGS. 12A to 12C has the same structure as that shown in FIGS. 11A and 11B. 12A is a top view of transistor 500A. 12B is a cross-sectional view of the transistor 500A in the channel length direction, and FIG. 12C is a cross-sectional view of the transistor 500A in the channel length direction. 12A is a cross-sectional view of the transistor 500A in the channel width direction. For clarity, some elements are omitted. The same can be said for other transistors included in the semiconductor device of one embodiment of the present invention, such as the transistor 550. can be applied.

[0240] The transistor 500A shown in FIGS. 12A to 12C includes an insulator 552, an insulator 513, and an insulator 514. 11A and 11B in that it has an insulator 404. In addition, the transistor 500A has an insulator 552 provided in contact with the side surface of the conductor 540a. In addition, the insulator 552 is provided in contact with the side surface of the conductor 540b, which is a difference between the transistor 500 and the transistor 500. Furthermore, transistor 500A differs from transistor 500A in that it does not have an insulator 520. It is different from the Ta500.

[0241] The transistor 500A having the configuration shown in FIGS. 12A to 12C includes an insulator 512 on an insulator 512. 513 is provided. In addition, the insulator 404 is provided on the insulator 574 and the insulator 513. It can be done.

[0242] In the transistor 500A having the configuration shown in FIGS. 12A to 12C, the insulator 514, the insulator 516, insulator 522, insulator 524, insulator 544, insulator 580, and insulator 57 4 is patterned, and the insulating material 404 covers them. The insulator 404 is formed on the top surface of the insulator 574, the side surface of the insulator 574, the side surface of the insulator 580, and the insulator The side of the body 544, the side of the insulator 524, the side of the insulator 522, the side of the insulator 516, the insulator The oxide 530 and the like are in contact with the side surface of the insulating body 514 and the top surface of the insulating body 513, respectively. , and is isolated from the outside by insulators 404 and 513.

[0243] The insulator 513 and the insulator 404 are made of at least hydrogen (e.g., hydrogen atoms, hydrogen molecules, etc.). It is preferable that the insulator 51 has a high function of suppressing the diffusion of water molecules. 3 and the insulator 404 are made of a material with high hydrogen barrier properties, such as silicon nitride or nitride. It is preferable to use silicon oxide, which prevents hydrogen and the like from diffusing into the oxide 530. This can suppress the deterioration of the characteristics of the transistor 500A. This can improve the reliability of the semiconductor device of one embodiment of the present invention.

[0244] Insulator 552 includes insulator 581, insulator 404, insulator 574, insulator 580, and The insulator 552 is provided in contact with the insulator 544. The insulator 552 suppresses the diffusion of hydrogen or water molecules. For example, the insulator 552 is preferably a material having a high hydrogen barrier property. An insulator such as silicon nitride, aluminum oxide, or silicon nitride oxide is used. In particular, silicon nitride is a material with high hydrogen barrier properties, so that the insulator 55 It is preferable to use a material with high hydrogen barrier properties as the insulator 552. As a result, impurities such as water or hydrogen are transported from the insulator 580 to the conductor 540a and the conductor 540b. Diffusion into the oxide 530 through the insulator 58 can be suppressed. The oxygen contained in the conductive material 540a is prevented from being absorbed by the conductive material 540b. As described above, the reliability of the semiconductor device of one embodiment of the present invention can be improved.

[0245] <Transistor variation 2> An example of the configuration of the transistor 500B will be described with reference to FIGS. 13A, 13B, and 13C. FIG. 13A is a top view of transistor 500B. FIG. 13B shows the transistor 500B shown in FIG. 13A with a dashed line. 13A. FIG. 13C is a cross-sectional view of the L1-L2 region indicated by the dashed line W1-W in FIG. 13A is a cross-sectional view of two parts. Note that in the top view of FIG. 13A, some elements are shown in a simplified form for clarity. The description is omitted.

[0246] Transistor 500B is a modification of transistor 500. Therefore, to avoid repetition, we will mainly focus on transistors. The differences from the controller 500 will be explained below.

[0247] The conductor 560 functioning as the first gate electrode is made up of the conductor 560a and the conductor 56 Conductor 560a has a conductor 560b on it. Conductor 560a is composed of hydrogen atoms, hydrogen molecules, water molecules, copper It is preferable to use a conductive material that has the function of suppressing the diffusion of impurities such as atoms. or 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 such a property.

[0248] The conductor 560a has a function of suppressing the diffusion of oxygen, and therefore the material of the conductor 560b In other words, by having the conductor 560a, the conductor 560 The oxidation of b is suppressed, and the decrease in electrical conductivity can be prevented.

[0249] In addition, the insulator 545 is formed so as to cover the upper and side surfaces of the conductor 560 and the side surface of the insulator 545. It is preferable to provide the insulator 544. The insulator 544 is a material that can absorb impurities such as water or hydrogen, and It is advisable to use an insulating material that has the function of suppressing the diffusion of oxygen. For example, aluminum oxide It is preferable to use titanium dioxide or hafnium oxide. Nesium, gallium oxide, germanium oxide, yttrium oxide, zirconium oxide, acid metal oxides such as lanthanum oxide, neodymium oxide or tantalum oxide, silicon oxide nitride or Silicon nitride or the like can be used.

[0250] By providing the insulator 544, oxidation of the conductor 560 can be suppressed. By providing the insulator 544, impurities such as water and hydrogen contained in the insulator 580 are absorbed into the transistor. This can prevent the diffusion of the electrons into the resistor 500B.

[0251] Transistor 500B has conductor 56 connected to a portion of conductor 542a and a portion of conductor 542b. Since the 0s overlap, the parasitic capacitance tends to be larger than that of the transistor 500. However, the operating frequency of the insulator 580 tends to be lower than that of the insulator 500. Since there is no need to provide an opening in the substrate 540 and fill in the conductor 560 or the insulator 545, High productivity compared to the transistor 500.

[0252] The configurations, structures, methods, and the like shown in this embodiment may be used in conjunction with other embodiments and examples. The configuration, structure, method, etc. can be used in appropriate combination.

[0253] (Embodiment 3) In this embodiment, an oxide semiconductor, which is a type of metal oxide, will be described.

[0254] The metal oxide preferably contains at least indium or zinc. In addition to these, aluminum, gallium, It is preferable that the material contains yttrium, tin, etc. Also, boron, silicon, titanium, etc. Iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, Selected from among odymium, hafnium, tantalum, tungsten, magnesium, cobalt, etc. One or more of these may be included.

[0255] <Classification of crystal structures> First, the classification of crystal structures in oxide semiconductors will be explained with reference to FIG. 15A. FIG. 15A shows an oxide semiconductor, typically IGZO (a metal oxide containing In, Ga, and Zn). FIG. 1 is a diagram illustrating the classification of crystal structures of metal oxides.

[0256] As shown in FIG. 15A, oxide semiconductors are broadly divided into "amorphous" and "non-amorphous" oxide semiconductors. ) and "Crystalline" and "Crystal" Also, among "Amorphous" there are those that are completely amorphous. Also, "Crystalline" contains CAAC (ca xis-aligned crystalline), nc(nanocrystall ine), and CAC (cloud-aligned composite). (excluding single crystal and poly crys tal). The classification of "Crystalline" includes single crystals. l, polycrystalline, and completely amorphous are excluded. Also, "Crystal" includes single crystal and p Contains poly crystal.

[0257] The structures within the bold frame in Figure 15A are "Amorphous" and "Cr It is an intermediate state between "crystal" and "new crystal" In other words, the structure is in the It is completely different from the unstable "Amorphous" and "Crystal" This can be rephrased as a structure in which:

[0258] The crystal structure of the film or substrate can be determined by X-ray diffraction (XRD). The crystallinity can be evaluated using the crystallinity spectrum. The GIXD (Grazing-Incidence) of CAAC-IGZO films The XRD spectrum obtained by the GIXD measurement is shown in Figure 15B. This is also called the membrane method or the Seemann-Bohlin method. The XRD spectrum obtained by the measurement is simply referred to as the XRD spectrum. The composition of the CAAC-IGZO film is approximately In:Ga:Zn=4:2:3 [atomic ratio]. The thickness of the CAAC-IGZO film shown in Figure 15B is 500 nm.

[0259] As shown in Figure 15B, the XRD spectrum of the CAAC-IGZO film shows clear crystalline Specifically, in the XRD spectrum of the CAAC-IGZO film, A peak indicating the c-axis orientation is detected near 2θ=31°. The peak intensity at 2θ=31° is detected at the angle It is asymmetrical about the axis.

[0260] The crystal structure of the film or substrate was also analyzed by nanobeam electron diffraction (NBED). Diffraction patterns (ultra-small) observed by electron diffraction It can be evaluated by the electron diffraction pattern. The folding pattern is shown in Figure 15C. Figure 15C shows the NB method in which the electron beam is incident parallel to the substrate. The diffraction pattern observed by ED is shown in Figure 15C. The composition of the film is approximately In:Ga:Zn=4:2:3 [atomic ratio]. In the diffraction method, electron diffraction is performed with a probe diameter of 1 nm.

[0261] As shown in Figure 15C, the diffraction pattern of the CAAC-IGZO film shows multiple patterns indicating c-axis orientation. Several spots are observed.

[0262] <<Structure of oxide semiconductor>> In addition, when focusing on the crystal structure, oxide semiconductors may be classified differently from those shown in FIG. 15A. For example, oxide semiconductors are classified into single-crystal oxide semiconductors and other non-single-crystal oxide semiconductors. As a non-single-crystal oxide semiconductor, for example, the above-mentioned CAAC-OS Non-single-crystal oxide semiconductors include polycrystalline oxide semiconductors, pseudo-crystalline oxide semiconductors, and nc-OS. Pseudo-amorphous oxide semiconductor (a-like OS) e semiconductor), amorphous oxide semiconductor, etc.

[0263] Here, we will explain the details of the above-mentioned CAAC-OS, nc-OS, and a-like OS. and provide an explanation.

[0264] [CAAC-OS] The CAAC-OS has multiple crystalline regions, each of which has a c-axis aligned in a specific direction. The specific direction is the thickness direction of the CAAC-OS film. , in the normal direction to the surface on which the CAAC-OS film is formed, or in the normal direction to the surface of the CAAC-OS film. The crystalline region is a region in which the atomic arrangement has periodicity. When viewed as a crystal arrangement, the crystalline region is also a region with a uniform lattice arrangement. The OS has a region where multiple crystalline regions are connected in the ab-plane direction, and this region has strain. The distortion may occur in a region where multiple crystal regions are connected. The area where the orientation of the lattice arrangement changes between a region with one lattice arrangement and a region with a different lattice arrangement. In other words, the CAAC-OS has a c-axis orientation and no clear orientation in the ab-plane direction. It is an oxide semiconductor that has not been

[0265] Each of the plurality of crystalline regions is made up of one or more minute crystals (maximum diameter 10 When a crystalline region is made up of a single microcrystal (crystals less than 1 nm in size), The maximum diameter of the crystalline region is less than 10 nm. When such crystal regions are formed, the size of the crystal regions may be on the order of several tens of nanometers.

[0266] In-M-Zn oxide (element M is aluminum, gallium, yttrium, sulphur, CAAC-OS is a material selected from the group consisting of aluminum, titanium, and other materials. The layer containing element M, zinc (Zn), and oxygen (hereinafter referred to as the In layer) is The layered crystal structure (layered structure) is composed of a layer containing oxygen (hereinafter referred to as the (M,Zn) layer). Indium and element M can be substituted for each other. Therefore, the (M, Zn) layer may contain indium. The In layer may contain Zn. For example, it is observed as a lattice image in a high-resolution TEM image.

[0267] For example, when the structure of the CAAC-OS film is analyzed using an XRD device, the θ / 2θ phase In the out-of-plane XRD measurement using a can, two peaks indicating the c-axis orientation were observed. The peak indicating the c-axis orientation is detected at or near θ=31°. ) may vary depending on the type and composition of the metal elements that make up the CAAC-OS.

[0268] For example, in the electron diffraction pattern of the CAAC-OS film, multiple bright spots (spots) Note that one spot and another spot are the incident electron beams that have passed through the sample. The spot (also called the direct spot) is the center of symmetry, and the points are observed at positions that are point-symmetric. can be.

[0269] When the crystalline region is observed from the specific direction, the lattice arrangement within the crystalline region is a hexagonal lattice. However, the unit cell is not necessarily a regular hexagon, and may be a non-regular hexagon. The above distortion may have a lattice arrangement such as a pentagon or heptagon. -In OS, clear grain boundaries were confirmed even near the strain. In other words, the formation of grain boundaries is suppressed by the distortion of the lattice arrangement. This is because the arrangement of oxygen atoms in the CAAC-OS is close-packed in the ab-plane direction. The bond distance between atoms changes when metal atoms are substituted. , it is believed that this is because distortion can be tolerated.

[0270] The crystal structure in which clear grain boundaries are observed is called polycrystal. The grain boundaries act as recombination centers, trapping carriers and forming transistors. It is highly likely that this will cause a decrease in on-state current and a decrease in field effect mobility. CAAC-OS, which has no visible grain boundaries, has a crystal structure suitable for the semiconductor layer of a transistor. It is one of the crystalline oxides containing Zn to form CAAC-OS. For example, In-Zn oxide and In-Ga-Zn oxide are This is preferable because it can suppress the generation of grain boundaries more effectively than oxides.

[0271] CAAC-OS is an oxide semiconductor with high crystallinity and no clear grain boundaries. Therefore, the CAAC-OS is less susceptible to the decrease in electron mobility caused by grain boundaries. In addition, the crystallinity of oxide semiconductors may be reduced by the incorporation of impurities or the generation of defects. Therefore, CAAC-OS is an oxide semiconductor with few impurities and defects (such as oxygen vacancies). Therefore, the physical properties of an oxide semiconductor having a CAAC-OS are stable. Therefore, oxide semiconductors having CAAC-OS are heat-resistant and highly reliable. C-OS is stable even under high temperatures (so-called thermal budget) in the manufacturing process. Therefore, using CAAC-OS for OS transistors increases the flexibility of the manufacturing process. It becomes possible to

[0272] [nc-OS] nc-OS is a material that can be used in microscopic areas (e.g., areas between 1 nm and 10 nm, especially areas between 1 nm and 10 nm). In other words, nc-OS has a periodic atomic arrangement in the region of 3 nm or less. It has small crystals. The size of the minute crystals is, for example, 1 nm or more and 10 nm or less. Since the size of these tiny crystals is between 1 nm and 3 nm, they are also called nanocrystals. In nc-OS, there is no regularity in the crystal orientation between different nanocrystals. Therefore, depending on the analytical method, nc-OS may be considered as a-like In some cases, it is difficult to distinguish between an OS and an amorphous oxide semiconductor. For example, in the case of an nc-OS film, , Structural analysis was performed using an XRD instrument, and out-of-plane analysis using θ / 2θ scan was performed. In the XRD measurement, no peaks indicating crystallinity were detected. However, electron beam circuits using electron beams with probe diameters larger than nanocrystals (e.g., 50 nm or larger) are being used. When electron diffraction (also called selected area electron diffraction) is performed, a diffraction pattern resembling a halo pattern is observed. On the other hand, for the nc-OS film, the size of the nanocrystals is close to or smaller than that of the nanocrystals. Electron beam diffraction (nanobeam) using an electron beam with a probe diameter (for example, 1 nm to 30 nm) When electron diffraction is performed, a ring-shaped region is formed around the direct spot. An electron diffraction pattern may be obtained in which multiple spots are observed.

[0273] [a-like OS] The a-like OS is an oxide semiconductor with a structure between the nc-OS and amorphous oxide semiconductor. A-like OS has pores or low density regions. The OS has lower crystallinity than the nc-OS and CAAC-OS. e-OS has a higher hydrogen concentration in the film than nc-OS and CAAC-OS.

[0274] <<Oxide semiconductor structure>> Next, the details of the above-mentioned CAC-OS will be explained. Regarding the formation of

[0275] [CAC-OS] CAC-OS is a type of metal oxide in which the elements constituting the metal oxide are 0.5 nm to 10 nm in size. Preferably, the material is unevenly distributed in a size of 1 nm to 3 nm or in the vicinity thereof. In the following, it is assumed that one or more metal elements are unevenly distributed in a metal oxide. The region having the metal element has a size of 0.5 nm to 10 nm, preferably 1 nm to 3 nm. A mixed state of particles with sizes of less than 1 m or close to that size is called a mosaic or patch state. .

[0276] Furthermore, CAC-OS is a material that is separated into a first region and a second region. The first regions are in a shape similar to a cloud, and the first regions are distributed throughout the film (hereinafter also referred to as a cloud shape). ) In other words, the CAC-OS is a mixture of the first area and the second area. It is a composite metal oxide having a structure in which

[0277] Here, the I ratio of the metal elements constituting the CAC-OS in the In-Ga-Zn oxide is The atomic ratios of n, Ga, and Zn are defined as [In], [Ga], and [Zn], respectively. For example, in the CAC-OS of In-Ga-Zn oxide, the first region is the region where [In] is larger than [In] in the composition of the CAC-OS film. The second region is a region where [Ga] is larger than [Ga] in the composition of the CAC-OS film. Or, for example, the first region has [In] higher than the [In] in the second region. In this region, [Ga] is larger than [Ga] in the first region. In addition, the second region has a larger [Ga] than the [Ga] in the first region and a smaller [I [n] is smaller than [In] in the first region.

[0278] Specifically, the first region is mainly composed of indium oxide, indium zinc oxide, etc. The second region is a region containing gallium oxide, gallium zinc oxide, etc. In other words, the first region is called a region in which In is the main component. The second region can be rephrased as a region containing Ga as the main component. It is possible.

[0279] Note that there are cases where a clear boundary between the first region and the second region cannot be observed. .

[0280] For example, in the case of CAC-OS in In-Ga-Zn oxide, energy dispersive X-ray diffraction (EDX) Optical method (EDX:Energy Dispersive X-ray spectrosc) The EDX mapping obtained using the opy revealed a region containing In as the main component (the first region). The structure has a structure in which a first region (a first region) and a region (a second region) mainly composed of Ga are unevenly distributed and mixed. It can be confirmed that this is the case.

[0281] When CAC-OS is used in a transistor, the conductivity due to the first region and the conductivity due to the second region are The insulating properties due to the region act complementary to each other to provide a switching function (On In other words, the CAC-OS and has a conductive function in a part of the material and an insulating function in a part of the material, and By separating the conductive function from the insulating function, Therefore, by using CAC-OS in transistors, This allows for a high on-state current (I on ), high field-effect mobility (μ), and good switching This allows for realizing a switching operation.

[0282] Oxide semiconductors have a variety of structures, each of which has different characteristics. The oxide semiconductors in Two or more of AC-OS, nc-OS, and CAAC-OS may be included.

[0283] <Transistors containing oxide semiconductors> Next, a case where the oxide semiconductor is used in a transistor will be described.

[0284] By using the oxide semiconductor for a transistor, a transistor with high field-effect mobility can be realized. Furthermore, a highly reliable transistor can be realized.

[0285] For the transistor, an oxide semiconductor with a low carrier concentration is preferably used. , the carrier concentration of the oxide semiconductor is 1×10 17 cm -3 Less than 1 × 10 15 c m -3 or less, more preferably 1 × 10 13 cm -3 Less than or equal to 1×10 11 cm -3 or less, more preferably 1 × 10 10 cm -3 Less than 1 x 10 -9 cm - 3 In order to reduce the carrier concentration of the oxide semiconductor film, The impurity concentration in the semiconductor film may be reduced to reduce the defect state density. A low impurity concentration and a low defect level density are called high purity intrinsic or substantially high purity intrinsic. The oxide semiconductor having a low carrier concentration is preferably a high-purity intrinsic or substantially high-purity intrinsic oxide. These are sometimes called compound semiconductors.

[0286] Furthermore, a highly purified intrinsic or substantially highly purified intrinsic oxide semiconductor film has a low density of defect states. Therefore, the trap level density may also be low.

[0287] In addition, the time required for the charges trapped in the trap levels of the oxide semiconductor to disappear is Therefore, the trap level density is high. A transistor in which a channel formation region is formed in an oxide semiconductor has unstable electrical characteristics. This may be the case.

[0288] Therefore, in order to stabilize the electrical characteristics of a transistor, the impurity concentration in the oxide semiconductor In order to reduce the impurity concentration in the oxide semiconductor, it is effective to reduce It is preferable to reduce the impurity concentration in the adjacent film. These include alkali metals, alkaline earth metals, iron, nickel, and silicon.

[0289] <Impurities> Here, the influence of each impurity in an oxide semiconductor will be described.

[0290] When oxide semiconductors contain silicon or carbon, which are elements of Group 14, they are oxidized. Defect levels are formed in semiconductors, which is why defects in silicon and carbon in oxide semiconductors The concentration of silicon and carbon near the interface with the oxide semiconductor (secondary ion mass spectrometry) (SIMS: Secondary Ion Mass Spectrometry) The concentration obtained is 2 x 10 18 atoms / cm 3 Less than or equal to 2 x 10 17 a toms / cm 3 The following applies.

[0291] In addition, when an oxide semiconductor contains an alkali metal or an alkaline earth metal, defect levels are formed. Therefore, alkali metals or alkaline earth metals may be included. Transistors using oxide semiconductors, which are widely used in semiconductors, tend to be normally on. Therefore, the concentration of alkali metals or alkaline earth metals in oxide semiconductors obtained by SIMS Degrees, 1 x 10 18 atoms / cm 3 Less than or equal to 2 x 10 16 atoms / cm 3 Do the following:

[0292] In addition, when nitrogen is contained in an oxide semiconductor, electrons that serve as carriers are generated, and As a result, the nitrogen-containing oxide semiconductor becomes a semiconductor. The transistors used for the oxide semiconductors tend to be normally on. Therefore, if nitrogen is contained, trap levels may be formed. Therefore, the electrical properties of the oxide semiconductor obtained by SIMS may become unstable. The nitrogen concentration in 19 atoms / cm 3 Less than 5 x 10 18 ato ms / cm 3 Less than or equal to 1×10 18 atoms / cm 3 The following are more preferred: Kuha 5 x 10 17 atoms / cm 3 Do the following:

[0293] In addition, hydrogen contained in oxide semiconductors reacts with oxygen that bonds with metal atoms to form water. When hydrogen enters the oxygen vacancy, the electron carrier In addition, some of the hydrogen atoms may bond with the oxygen atoms that bond with the metal atoms, forming chiral ions. Therefore, it is necessary to use an oxide semiconductor containing hydrogen. Therefore, the hydrogen in the oxide semiconductor tends to cause a transistor to be normally on. It is preferable that the amount of Si in the oxide semiconductor is as small as possible. The hydrogen concentration obtained by MS was 1×10 20 atoms / cm 3 Less than 1x, preferably 10 19 atoms / cm 3 less than 5 × 10 18 atoms / cm 3less than , and more preferably 1 × 10 18 atoms / cm 3 Make it less than.

[0294] By using an oxide semiconductor with sufficiently reduced impurities for a channel formation region of a transistor, This makes it possible to impart stable electrical properties.

[0295] The configurations, structures, methods, and the like shown in this embodiment may be used in conjunction with other embodiments and examples. The configuration, structure, method, etc. can be used in appropriate combination.

[0296] (Fourth embodiment) In this embodiment, an application example of the above-described semiconductor device will be described.

[0297] [Semiconductor wafers, chips] 16A shows a top view of the substrate 711 before the dicing process is performed. For example, a semiconductor substrate (also called a "semiconductor wafer") can be used as 711. A plurality of circuit regions 712 are provided on the substrate 711. a semiconductor device according to one embodiment of the present invention, a CPU, an RF tag, an image sensor, or the like It can be established.

[0298] Each of the multiple circuit regions 712 is surrounded by an isolation region 713. A separation line (also called a "dicing line") 714 is set at a position where the separation line overlaps with the separation line. By cutting the substrate 711 along 714, a chip 715 including a circuit region 712 is formed on the substrate. The chip 715 can be cut out from the chip 711. An enlarged view of the chip 715 is shown in FIG.

[0299] In addition, a conductor or a semiconductor layer may be provided in the separation region 713. By providing a semiconductor layer, ESD that may occur during the dicing process is mitigated, and the dicing process In general, the dicing process involves cooling the substrate, grinding it, and Pure water with reduced resistivity due to the dissolution of carbon dioxide gas, etc., for the purposes of removing debris and preventing static electricity. By providing a conductor or semiconductor layer in the separation region 713, The amount of pure water used can be reduced, thereby reducing the production cost of semiconductor devices. Furthermore, the productivity of the semiconductor device can be improved.

[0300] The semiconductor layer provided in the separation region 713 has a band gap of 2.5 eV or more and 4.2 e It is preferable to use a material with an energy of 2.7 eV or less, preferably 2.7 eV or more and 3.5 eV or less. Such materials allow the accumulated charge to be slowly discharged, thus reducing the risk of ESD damage. This suppresses the sudden movement of charges due to electrostatic discharge, making it less likely that electrostatic breakdown will occur.

[0301] [Electronic Components] An example of applying the chip 715 to an electronic component will be described with reference to FIG. The electronic components are also called semiconductor packages or IC packages. There are multiple standards and names depending on the direction of insertion and the shape of the terminal.

[0302] The electronic component is assembled with the semiconductor device shown in the above embodiment in the assembly process (post-process). The semiconductor device is completed by combining it with other components.

[0303] The post-process will be described using the flowchart shown in FIG. After the element substrate having the semiconductor device shown in the embodiment is completed, the back surface (semiconductor The back surface (the surface on which no conductor devices are formed) is ground (step S 721) By thinning the element substrate through grinding, warping of the element substrate is reduced, and the electronic components are This allows for the product to be made smaller.

[0304] Next, a "dicing process" is performed to separate the element substrate into a plurality of chips (chips 715). (Step S722). Then, the separated chips are individually picked up and attached to the lead frame. Then, a "die bonding process" is performed (step S723). During the process, the chip and lead frame are joined using resin or tape. The appropriate method is selected depending on the product. The chip may be bonded onto a poser substrate.

[0305] Next, the leads of the lead frame and the electrodes on the chip are electrically connected with thin metal wires. The "wire bonding process" is carried out to electrically connect the thin metal wires (step S724). Silver wire or gold wire can be used for wire bonding. Bonding or wedge bonding can be used.

[0306] The wire-bonded chip is sealed with epoxy resin in the "encapsulation process (molding)" The sealing process is then carried out (step S725). The chip is filled with resin, and the circuitry built into the chip and the wires connecting the chip and leads are machined. It can protect from external mechanical forces and also prevents deterioration of characteristics (reduced reliability) due to moisture and dust. can be reduced.

[0307] Next, a "lead plating process" is carried out to plate the leads of the lead frame (step (Step S726). The plating process prevents the leads from rusting and allows them to be mounted on a printed circuit board later. This allows for more reliable soldering during the process. The leads are then cut and shaped. Then, a "molding step" is carried out (step S727).

[0308] Next, a "marking process" is carried out to print (mark) the surface of the package. Then, an "inspection process" is carried out to check whether the external appearance is good or not, whether there is any malfunction, etc. (Step S728). After passing through the "process" (step S729), the electronic component is completed.

[0309] A perspective view of the completed electronic component is shown in FIG. 17B. As an example, a perspective schematic diagram of a QFP (Quad Flat Package) is shown. The electronic component 750 shown in FIG. 17B shows leads 755 and semiconductor device 753. The semiconductor device 753 can be any of the semiconductor devices described in the above embodiment modes. do.

[0310] The electronic component 750 shown in FIG. 17B is mounted on, for example, a printed circuit board 752. A plurality of electronic components 750 are combined and electrically connected on a printed circuit board 752. By connecting the components together, a substrate (mounted substrate 754) on which electronic components are mounted is completed. The substrate 754 is used in electronic devices and the like.

[0311] [Electronic equipment] Next, examples of electronic devices including the semiconductor device according to one embodiment of the present invention or the electronic component will be described. Explanations will be given.

[0312] Examples of electronic devices using the semiconductor device or electronic component according to one embodiment of the present invention include televisions, monitors, and the like. Display devices such as monitors, lighting devices, desktop or notebook personal computers , word processors, DVDs (Digital Versatile Discs), etc. Image playback devices that play still images or videos stored on recording media, portable CD players , radio, tape recorder, headphone stereo, stereo, table clock, wall clock, Wireless telephone handsets, transceivers, mobile phones, car phones, portable game consoles, tablets large game machines such as pachinko machines, calculators, portable information terminals ("mobile information terminals") ), electronic organizers, e-book terminals, electronic translators, voice input devices, video cameras, Digital still cameras, electric shavers, microwave ovens and other high-frequency heating devices, electric rice cookers, Washing machines, vacuum cleaners, water heaters, electric fans, hair dryers, air conditioners, humidifiers, dehumidifiers Air conditioning equipment such as humidifiers, dishwashers, dish dryers, clothes dryers, futon dryers, electric refrigerators, Electric freezers, electric refrigerator-freezers, freezers for DNA storage, flashlights, tools such as chainsaws , smoke detectors, medical equipment such as dialysis machines. conveyors, elevators, escalators, industrial robots, power storage systems, power balance Examples include industrial equipment such as energy storage devices for standardization and smart grids.

[0313] In addition, mobile objects propelled by electric motors using power from a power storage device are also included in the category of electronic devices. The above-mentioned mobile units include, for example, electric vehicles (EVs), internal combustion engines, and Hybrid electric vehicles (HEV) and plug-in hybrid electric vehicles (PHEV) , tracked vehicles in which these tires and wheels are converted into tracks, and motorized vehicles including electrically assisted bicycles. Bicycles, motorcycles, electric wheelchairs, golf carts, small or large boats, submarines, helicopters Examples include robots, aircraft, rockets, satellites, space probes, planetary probes, and spacecraft. do.

[0314] The semiconductor device or electronic component according to one aspect of the present invention is a communication device built into these electronic devices. It can be used in communication devices, etc.

[0315] Electronic devices include sensors (force, displacement, position, velocity, acceleration, angular velocity, rotation speed, distance, light, liquid , magnetic, temperature, chemical, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, (including those that measure humidity, gradient, vibration, odor, or infrared rays) good.

[0316] Electronic devices can have various functions. For example, they can store various information (still images, videos, Functions for displaying text images, etc. on the display, touch panel function, calendar, date, or The function of the device is to display the time, run various software (programs), and The device has functions such as transmitting and receiving data, and reading programs or data recorded on a recording medium. This can be done.

[0317] An example of an electronic device is shown in Fig. 18 and Figs. 19A to 19F. The device 8000 is an example of an electronic device including a semiconductor device 8004 according to one embodiment of the present invention. Specifically, the display device 8000 corresponds to a display device for receiving TV broadcasts, and has a housing 8001 , a display portion 8002, a speaker portion 8003, a semiconductor device 8004, a power storage device 8005, etc. The semiconductor device 8004 according to one embodiment of the present invention is provided inside the housing 8001. The semiconductor device 8004 can hold control information, control programs, etc. In addition, the semiconductor device 8004 has a communication function, and the display device 8000 can be used as an IoT device. The display device 8000 can be operated by receiving power from a commercial power source. Alternatively, power stored in the power storage device 8005 can be used.

[0318] The display unit 8002 is a display device having a light emitting element such as a liquid crystal display device or an organic EL element in each pixel. Optical display devices, electrophoretic display devices, DMD (Digital Micromirror Display) device), PDP (Plasma Display Panel), FED (Fie A display device such as a 100% Emission Display can be used.

[0319] In addition to TV broadcast reception, display devices are also used for personal computers and advertising displays. This includes all display devices for displaying information, such as:

[0320] In FIG. 18, a stationary lighting device 8100 is a semiconductor device according to one embodiment of the present invention. 8103. Specifically, the lighting device 8100 is an example of an electronic device using the housing 8101. 18, the semiconductor device 8103 includes a light source 8102, a semiconductor device 8103, a power storage device 8105, and the like. The conductor device 8103 is attached to the ceiling 8104 on which the housing 8101 and the light source 8102 are installed. Although the semiconductor device 8103 is shown as being provided inside the housing 8101, The semiconductor device 8103 can improve the brightness of the light source 8102. The semiconductor device 8103 can store information, control programs, etc. This allows the lighting device 8100 to function as an IoT device. The lighting device 8100 can receive power from a commercial power source or can receive power stored in a power storage device. The generated power can also be used.

[0321] In addition, FIG. 18 illustrates a lighting device 8100 of a fixed type provided on a ceiling 8104. However, in the semiconductor device according to one embodiment of the present invention, the sidewall 8405, It can also be used in a fixed lighting device installed on a floor 8406, a window 8407, etc. It can also be used as a tabletop lighting device.

[0322] The light source 8102 can be an artificial light source that artificially obtains light using electricity. Specifically, this applies to incandescent lamps, discharge lamps such as fluorescent lamps, and light-emitting devices such as LEDs and organic EL elements. An example of the artificial light source is a light element.

[0323] In FIG. 18, an air conditioner having an indoor unit 8200 and an outdoor unit 8204 8 illustrates an example of an electronic device including a semiconductor device 8203 according to one embodiment of the present invention. The indoor unit 8200 includes a housing 8201, an air outlet 8202, a semiconductor device 8203, a power storage device 8204, and a power supply 8205. 18, the semiconductor device 8203 is provided in an indoor unit 8200. However, the semiconductor device 8203 may be provided in an outdoor unit 8204. Alternatively, the semiconductor device 8203 may be provided in both the indoor unit 8200 and the outdoor unit 8204. The semiconductor device 8203 may be used to transmit control information for an air conditioner and a control program. The semiconductor device 8203 has a communication function and can store programs. Air conditioners can function as IoT devices. The power supply can be supplied from a commercial power source, and the power can be stored in the power storage device 8205. The generated power can also be used.

[0324] In addition, Figure 18 shows a separate type air conditioner consisting of an indoor unit and an outdoor unit. However, it is an integrated air conditioner that has the functions of both an indoor unit and an outdoor unit in a single housing. The semiconductor device according to one embodiment of the present invention can be used for the conditioner.

[0325] In FIG. 18, an electric refrigerator-freezer 8300 includes a semiconductor device 830 according to one embodiment of the present invention. 8301. Specifically, the electric refrigerator-freezer 8300 is an example of an electronic device using the housing 8301. , a refrigerator door 8302, a freezer door 8303, a semiconductor device 8304, a power storage device 8305, etc. In FIG. 18, a power storage device 8305 is provided inside a housing 8301. The semiconductor device 8304 controls the electric refrigerator-freezer 8300 and stores control information and a control program. The semiconductor device 8304 has a communication function, and can The 8300 can function as an IoT device. The power storage device 8305 can receive power from a commercial power source or can use the power stored in the power storage device 8305. Force can also be used.

[0326] FIG. 19A shows an example of a wristwatch-type mobile information terminal. 101, a display unit 6102, a band 6103, an operation button 6105, etc. The portable information terminal 6100 includes a secondary battery and a semiconductor device or a The semiconductor device or electronic component according to one aspect of the present invention is provided in a portable information terminal 61. By using this in the mobile information terminal 6100, it is possible to function as an IoT device. do.

[0327] 19B shows an example of a mobile phone. A mobile information terminal 6200 includes a housing 6201 In addition to the display unit 6202 incorporated in the It is equipped with the 6205 and other models.

[0328] The portable information terminal 6200 also has a fingerprint sensor 6209 in an area overlapping the display unit 6202. The fingerprint sensor 6209 may be an organic optical sensor. Fingerprints are unique to each individual. Therefore, the fingerprint sensor 6209 can acquire a fingerprint pattern and perform personal authentication. The light emitted from the display unit 6202 is used as a light source for acquiring a fingerprint pattern by the fingerprint sensor 6209. The light generated can be used.

[0329] The portable information terminal 6200 includes a secondary battery and a semiconductor device according to one embodiment of the present invention. The semiconductor device or electronic component according to one aspect of the present invention is provided as a portable information device. By using the information terminal 6200, the mobile information terminal 6200 functions as an IoT device. It is possible.

[0330] 19C shows an example of a cleaning robot. The cleaning robot 6300 is housed in a housing 630 1, a display unit 6302 arranged on the top surface, a plurality of cameras 6303 arranged on the side, and a brush 6 304, an operation button 6305, various sensors, etc. Although not shown, the cleaning robot The cleaning robot 6300 is equipped with tires, a suction nozzle, etc. It moves, detects dust 6310, and sucks up the dust from the suction port on the bottom. Cut.

[0331] For example, the cleaning robot 6300 analyzes the image captured by the camera 6303 and detects the walls, furniture, etc. It can also determine whether there are obstacles such as steps. If an object that is likely to get tangled in the brush 6304 is detected, the rotation of the brush 6304 is stopped. The cleaning robot 6300 includes a secondary battery and a battery according to one embodiment of the present invention. The semiconductor device or electronic component according to one aspect of the present invention is provided. By using it in the Cleaning Robot 6300, the Cleaning Robot 6300 can function as an IoT device. It can be done.

[0332] Figure 19D shows an example of a robot. The robot 6400 shown in Figure 19D performs the following operations: Device 6409, illuminance sensor 6401, microphone 6402, upper camera 6403, A peaker 6404, a display unit 6405, a lower camera 6406 and an obstacle sensor 6407, It is equipped with a moving mechanism 6408.

[0333] The microphone 6402 has the function of detecting the user's voice and environmental sounds. The speaker 6404 has a function of emitting sound. The phone 6402 and the speaker 6404 can be used to communicate with the user. It is possible to do this.

[0334] The display unit 6405 has a function of displaying various information. The display unit 6405 can display information desired by the user. The display unit 6405 may be a detachable information terminal. By placing it in a fixed position on the robot 6400, charging and data transfer can be performed. This makes it possible.

[0335] The upper camera 6403 and the lower camera 6406 capture images of the surroundings of the robot 6400. The obstacle sensor 6407 also detects the obstacles by using the moving mechanism 6408. Robot 6 can detect the presence or absence of obstacles in its path as it moves forward. 400 uses an upper camera 6403, a lower camera 6406, and an obstacle sensor 6407. The light-emitting device according to one embodiment of the present invention can recognize the surrounding environment and move safely. can be used for the display portion 6405.

[0336] The robot 6400 includes a secondary battery and a semiconductor device or The semiconductor device or electronic component according to one embodiment of the present invention is provided by a robot 6400. By using this, the robot 6400 can function as an IoT device.

[0337] FIG. 19E shows an example of an air vehicle. The air vehicle 6500 shown in FIG. 19E has a propeller. 6501, a camera 6502, and a battery 6503, and has the capability to fly autonomously. It has.

[0338] For example, image data captured by the camera 6502 is stored in the electronic component 6504. The child component 6504 analyzes image data and detects whether there are any obstacles when moving. Also, the electronic component 6504 can detect the change in the storage capacity of the battery 6503. The flying object 6500 has a battery remaining capacity according to an embodiment of the present invention. The semiconductor device or electronic component according to one aspect of the present invention includes: By using this in the Air Vehicle 6500, the Air Vehicle 6500 can function as an IoT device. can be done.

[0339] FIG. 19F shows an example of a car. The car 7160 has an engine, tires, brakes, and The car 7160 has a brake, a steering device, a camera, etc. The car 7160 has a vehicle interior according to one embodiment of the present invention. The present invention relates to a semiconductor device or electronic component. By using this product in a car 7160, the car 7160 can function as an IoT device. This can be done.

[0340] The configurations, structures, methods, etc. shown in this example may be used in other embodiments and examples. The structure, method, etc. can be used in appropriate combination.

[0341] (Embodiment 5) The OS transistors described in this specification and the like are used to realize normally-off CPUs ("Noff"). It is also called "Noff-CPU". Normally-off transistors are non-conducting (also called off-state) even when the voltage is 0V. It is an integrated circuit containing a resistor.

[0342] The Noff-CPU stops supplying power to circuits that are not required to operate. The circuit can be put into a standby state. When the power supply is stopped and the circuit is in a standby state, No power is consumed. Therefore, the Noff-CPU can minimize power consumption. In addition, the Noff-CPU can maintain the settings and other necessary functions even if the power supply is cut off. It can retain information for a long period of time. When it returns from standby mode, the power supply to the circuit is resumed. It is only necessary to reset the standby state, and there is no need to rewrite the setting conditions. In this way, the No-off CPU can recover quickly without significantly slowing down its operation speed. This significantly reduces power consumption.

[0343] Noff-CPU is used in the IoT (Internet of Things) field, for example. IoT end devices (also called "endpoint microcomputers") 803 and other small-scale systems It can be suitably used for

[0344] Figure 20 shows the hierarchical structure of IoT networks and the trend of required specifications. The power consumption 804 and processing performance 805 are shown as examples. It is roughly divided into the cloud field 801, which is the upper layer, and the embedded field 802, which is the lower layer. The cloud field 801 includes, for example, servers. The embedded field 802 includes, for example, machines. , industrial robots, automotive equipment, home appliances, etc.

[0345] The higher the layer, the more important it is to have high processing performance rather than low power consumption. In 801, high-performance CPUs, high-performance GPUs, large-scale SoCs, etc. are used. Low power consumption is required rather than high processing performance, and the number of devices is increasing explosively. The semiconductor device according to one embodiment of the present invention is suitable for use in a communication device of an IoT terminal device that requires low power consumption. It can be used appropriately.

[0346] The term "endpoint" refers to the terminal area of ​​the embedded field 802. The devices used in this project are, for example, those used in factories, home appliances, infrastructure, agriculture, etc. This applies to microcontrollers.

[0347] Figure 21 shows an example of an application of an endpoint microcontroller in factory automation. The factory 884 is connected to the cloud via the Internet. Cloud 883 is also connected to Home 8 via the Internet. 81 and office 882. The internet line is a wired communication system. For example, in the case of a wireless communication system, the communication device may include the The semiconductor device according to the present invention can be used to implement a fourth generation mobile communication system (4G) or a fifth generation mobile communication system. Wireless communication can be performed in accordance with communication standards such as the 5G mobile communication system. 84 may be connected to a factory 885 and a factory 886 via an internet line.

[0348] The factory 884 has a master device (control device) 831. The master device 831 It has a function to connect to the cloud 883 and send and receive information. The IoT terminal device 841 includes multiple industrial robots 842, and M2M (Mach The M2M interface is connected via a Machine to Machine (M2M) interface 832. The interface 832 may be, for example, an industrial Ethernet ( "Ethernet" is a registered trademark) and local 5G, a type of wireless communication method. Good too.

[0349] Factory managers can manage the factory from home 881 or office 882 via cloud 883. You can connect to the site 884 to check the operation status. It is possible to give location instructions, measure takt time, etc.

[0350] In recent years, the introduction of IoT into factories has been progressing worldwide, calling them "smart factories." In the case of smart factories, it is not just inspection and audit using endpoint microcomputers, Cases have been reported in which it has also been used to detect faults and predict abnormalities.

[0351] Small-scale systems such as endpoint microcontrollers consume a large amount of power during operation. Since the power consumption is often small, the power saving effect of the Noff-CPU during standby operation is large. On the other hand, in the embedded field of IoT, quick response is sometimes required, but Noff-CP By using U, high-speed recovery from standby operation can be achieved.

[0352] The configurations, structures, methods, and the like shown in this embodiment may be used in conjunction with other embodiments and examples. The configuration, structure, method, etc. can be used in appropriate combination. [Example]

[0353] In this example, an OS-FET that can be used for a semiconductor device according to one embodiment of the present invention The cutoff frequency was determined by simulation and the results are now explained.

[0354] Cutoff frequency (f T ) can be calculated using the following formula 1.

[0355]

number

[0356] where C g is the gate capacitance of the OS-FET, gm is the mutual conductance. Transconductance g at drain voltage m can be calculated using the following formula 2: .

[0357]

number

[0358] In the above formula 2, V g is the gate voltage of the OS-FET, I d is the drain current, V d teeth is the drain voltage.

[0359] The cutoff frequency was calculated using Silvaco's device simulator Atlas 3D. The structure of the OS-FET used in the calculation is shown in Figures 22A to 22C. 22B is a schematic cross-sectional view in the L-length direction at the center of the channel of an OS-FET. 22C is a schematic cross-sectional view of the center of the channel of an OS-FET in the W width direction. FIG. 2 is a schematic cross-sectional view of a source region or a drain region of an OS-FET in the W-width direction.

[0360] In FIGS. 22A to 22C, the OS-FETs are BGE, BGI1, BGI2, and OS 1, OS2, SD, TGI, and TGE. BGE serves as a back gate electrode. The TGE functions as a gate electrode (also called a top gate electrode). and OS2 are metal oxides with a stacked structure. SD are source and drain electrodes, respectively. It functions as one of the input electrodes, or the other of the source or drain electrodes. 1 and BGI2 are stacked gate insulating films provided between BGE and OS1. The TGI functions as a gate insulating film provided between the OS2 and the TGE. do.

[0361] For OS1, a metal oxide with an atomic ratio of In:Ga:Zn=1:3:4 was used. As OS2, a metal oxide with an atomic ratio of In:Ga:Zn=4:2:3 was used.

[0362] In addition, L in FIG. 22A, that is, the width of the TGE, indicates the channel length, and in FIG. 22B, W in the figure, that is, the width of OS1 and OS2, indicates the channel width.

[0363] Next, Table 1 shows the calculation conditions.

[0364] [Table 1]

[0365] The calculation results for the cutoff frequency of the OS-FET obtained under the above conditions are shown in Figure 23. In the figure, the horizontal axis is the drain voltage of the OS-FET (unit: V), and the vertical axis is the cutoff frequency f T (unit In the above calculation, the gate voltage and the drain voltage are assumed to be the same value. The channel length and width of the OS-FET were set to 30 nm and 30 nm, respectively.

[0366] Looking at the results in Figure 23, when the drain voltage is 1 V, the cutoff frequency of the OS-FET is 38 .6GHz, when the drain voltage is 2V, the cutoff frequency is 71.5GHz, when the drain voltage is When the drain voltage is 3V, the cutoff frequency is 104.4GHz, and when the drain voltage is 4V, the cutoff frequency is 132.8GHz, and when the drain voltage was 5V, the cutoff frequency was 160.1GHz. By setting the drain voltage to 3V or more, a cutoff frequency of 100GHz or more can be obtained. was confirmed by calculation.

[0367] From the above calculation results, it can be seen that an OS-FET can be suitably used in a semiconductor device according to one embodiment of the present invention. I found that it is possible.

[0368] The configurations, structures, methods, etc. shown in this embodiment may be the same as those shown in other embodiments. It can be used in appropriate combination. [Explanation of symbols]

[0369] :L1: layer, L2: layer, L3: layer, L3A: layer, L3B: layer, L4: layer, 5G: local , 10: semiconductor device, 10A: semiconductor device, 10B: semiconductor device, 11: antenna array 11A: Antenna, 12: Transmission and reception control device, 12A: Transmission and reception control device, 12B: Transmission and reception Control device, 13: signal processing device, 14: processor, 15: GPU, 16: power control device , 16A: Power supply control device, 16B: Power supply control device, 17: PLD, 18: Storage device, 18 A: Storage device, 18B: Storage device, 18C: Storage device, 18D: Storage device, 18E: Storage Device, 18F: Storage device, 18G: Storage device, 18H: Storage device, 19: Display device, 19 A: Gate driver, 19B: Display area, 20: Sensor module, 24: Capacitor, 111 : memory element, 112: transistor, 113: capacitance, 114: node, 115: transistor starter, 116: transistor, 123: terminal, 124: terminal, 126: wiring, 311: substrate Plate, 313: semiconductor region, 314a: low resistance region, 314b: low resistance region, 315: insulating body, 316: conductor, 320: insulator, 322: insulator, 324: insulator, 326: insulator body, 328: conductor, 330: conductor, 350: insulator, 352: insulator, 354: insulator body, 356: conductor, 360: insulator, 362: insulator, 364: insulator, 366: conductor body, 370: insulator, 372: insulator, 374: insulator, 376: conductor, 380: insulation body, 382: insulator, 384: insulator, 386: conductor, 404: insulator, 500: transistor Transistor, 500A: Transistor, 500B: Transistor, 503: Conductor, 503 a: conductor, 503b: conductor, 510: insulator, 512: insulator, 513: insulator, 5 14: Insulator, 516: Insulator, 518: Conductor, 520: Insulator, 522: Insulator, 5 24: insulator, 530: oxide, 530a: oxide, 530b: oxide, 540a: conductor conductor, 540b: conductor, 542: conductor, 542a: conductor, 542b: conductor, 543 a: Region, 543b: Region, 544: Insulator, 545: Insulator, 546: Conductor, 548 : conductor, 550: transistor, 550A: transistor, 552: insulator, 560: Conductor, 560a: Conductor, 560b: Conductor, 574: Insulator, 580: Insulator, 58 1: insulator, 582: insulator, 586: insulator, 600: capacitance, 610: conductor, 612 : conductor, 620: conductor, 630: insulator, 640: insulator, 650: transistor, 652: low-temperature buffer layer, 54: semiconductor layer, 656: semiconductor layer, 658: conductor, 711 : Substrate, 712: Circuit area, 713: Separation area, 714: Separation line, 715: Chip, 75 0: Electronic components, 752: Printed circuit boards, 753: Semiconductor devices, 754: Mounting boards, 755 : Lead, 801: Cloud field, 802: Embedded field, 804: Power consumption, 805: Processing performance, 831: Master device, 832: M2M interface, 841: IoT End-use equipment, 842: Industrial robots, 881: Home, 882: Office, 883: Classroom Udo, 884: Factory, 885: Factory, 886: Factory, 900: Radio Transceiver, 900A: Radio transceiver, 901: low noise amplifier, 902: band pass filter, 903: mixer 904: Bandpass filter, 905: Demodulator, 906: Decoder circuit, 911: Power -Amplifier, 912: Bandpass filter, 913: Mixer, 914: Bandpass filter , 915: Modulator, 916: Decoder circuit, 921: Duplexer, 922: Local oscillator, 93 1: Antenna, 941: Signal, 942: Signal, 943: Signal, 944: Signal, 2001: Wiring, 2005: Wiring, 2006: Wiring, 6100: Mobile information terminal, 6101: Housing, 6 102: display unit, 6103: band, 6105: operation button, 6200: mobile information terminal, 6201: Housing, 6202: Display, 6203: Operation buttons, 6204: Speaker, 62 05: Microphone, 6209: Fingerprint sensor, 6300: Cleaning robot, 6301: Housing Body, 6302: Display unit, 6303: Camera, 6304: Brush, 6305: Operation button, 6310: Garbage, 6400: Robot, 6401: Light sensor, 6402: Microphone 6403: Upper camera, 6404: Speaker, 6405: Display, 6406: Lower camera camera, 6407: obstacle sensor, 6408: moving mechanism, 6409: computing unit, 6500: Aircraft, 6501: Propeller, 6502: Camera, 6503: Battery, 6504: Electronics Parts, 7160: Automobiles, 8000: Display devices, 8001: Housings, 8002: Display units, 8 003: Speaker unit, 8004: Semiconductor device, 8005: Power storage device, 8100: Lighting device , 8101: Housing, 8102: Light source, 8103: Semiconductor device, 8104: Ceiling, 8105 : Power storage device, 8200: Indoor unit, 8201: Housing, 8202: Air outlet, 8203: Semiconductor Equipment, 8204: Outdoor unit, 8205: Power storage device, 8300: Electric refrigerator-freezer, 8301: Housing, 8302: Refrigerator door, 8303: Freezer door, 8304: Semiconductor device, 8305 : Storage device, 8405: Side wall, 8406: Floor, 8407: Window

Claims

1. a first layer, a second layer, a third layer, and a fourth layer; the first layer includes a first transceiver control unit, a signal processing unit, a processor, a GPU, a first power control unit, and a PLD; the second layer includes a second transmission / reception control device and a second power control device; the third layer includes a storage device and a display device; the fourth layer having an antenna array for wireless communication; the second layer has a region located above the first layer; the third layer has a region overlapping with the first layer via the second layer and a region overlapping with the first layer without the second layer therebetween; The fourth layer has a region located above the third layer.

2. a first layer, a second layer, a third layer, and a fourth layer; the first layer includes a first transceiver control unit, a signal processing unit, a processor, a GPU, a first power control unit, and a PLD; the second layer includes a second transmission / reception control device and a second power control device; the third layer includes a storage device and a display device; the fourth layer having an antenna array for wireless communication; the second layer has a region located above the first layer; the third layer has a first region overlapping with the first layer via the second layer and a second region overlapping with the first layer without the second layer therebetween; the fourth layer has a region located above the third layer; the memory device includes a first transistor, a second transistor, and a third transistor; In the first region, the first transistor has a region overlapping with the first transmission / reception control device; In the first region, the second transistor has an area overlapping with the first power supply control device; In the second region, the third transistor has a region overlapping with the display device.

Images