Semiconductor device

Abstract

To provide a battery control circuit, a battery protection circuit, a power storage device, a semiconductor device, a vehicle, an electronic appliance, etc. with a novel structure, a structure of lower consumption power, or a structure with a high degree of integration.SOLUTION: A semiconductor device has: a first transistor having a first conductor and a first semiconductor on the first conductor; a first insulator on the first transistor; a second conductor provided in an opening in the first insulator; a second transistor on the first insulator; and a third conductor on the second transistor. The first conductor functions as a source electrode or a drain electrode of the first transistor. The first semiconductor and the second conductor overlap with each other. The second conductor and the third conductor overlap with each other. The third conductor and the second transistor overlap with each other. The first semiconductor and the second transistor are electrically connected to each other through the second conductor and the third conductor.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] One aspect of the present invention relates to a semiconductor device and a method of operating the semiconductor device. Further, one aspect of the present invention relates to a battery control circuit, a battery protection circuit, a power storage device, an electronic device, and an electrical device.

[0002] Note that one aspect of the present invention is not limited to the above technical field. The technical field of the invention disclosed in this specification and the like relates to an object, a method, or a manufacturing method. Alternatively, one aspect of the present invention relates to a process, a machine, a manufacture, or a composition of matter. Therefore, more specifically, as the technical field of one aspect of the present invention disclosed in this specification, a display device, a light-emitting device, a power storage device, an imaging device, a storage device, a driving method thereof, or a manufacturing method thereof can be cited as an example.

Background Art

[0003] Power storage devices (also referred to as batteries or secondary batteries) have come to be used in a wide range of fields from small electronic devices to automobiles. As the application range of batteries expands, applications using battery stacks having a multi-cell configuration in which a plurality of battery cells are connected in series are increasing.

[0004] Power storage devices are provided with a circuit for grasping abnormalities during charge and discharge such as over-discharge, over-charge, over-current, or short circuit. In this way, in a circuit for protecting and controlling a battery, data such as voltage and current is acquired in order to detect abnormalities during charge and discharge. Further, in such a circuit, control such as stopping charge and discharge and cell balancing is performed based on the observed data.

[0005] Patent Document 1 discloses a protection IC that functions as a battery protection circuit. Patent Document 1 discloses a protection IC that is provided with a plurality of comparators (comparators) inside and compares a reference voltage with the voltage of a terminal to which a battery is connected to detect an abnormality during charge and discharge.

[0006] Further, Patent Document 2 discloses a battery state detection device that detects a micro short circuit in a secondary battery and a battery pack incorporating the same.

[0007] Also, Patent Document 3 discloses a protection semiconductor device that protects a battery pack in which cells of a secondary battery are connected in series.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0009] One aspect of the present invention aims to provide novel battery control circuits, battery protection circuits, power storage devices, semiconductor devices, vehicles, electronic devices, etc. Or, one aspect of the present invention aims to provide battery control circuits, battery protection circuits, power storage devices, semiconductor devices, vehicles, electronic devices, etc. with low power consumption. Or, one aspect of the present invention aims to provide battery control circuits, battery protection circuits, power storage devices, semiconductor devices, vehicles, electronic devices, etc. with high integration.

[0010] Note that the problems of one aspect of the present invention are not limited to the problems listed above. The problems listed above do not prevent the existence of other problems. Other problems are those not mentioned in this item and described below. Problems not mentioned in this item can be derived by those skilled in the art from the descriptions in the specification, drawings, etc., and can be appropriately extracted from these descriptions. Note that one aspect of the present invention solves at least one of the problems listed above and / or other problems.

Means for Solving the Problems

[0011] One aspect of the present invention is a semiconductor device having a first transistor having a first conductor and a first semiconductor on the first conductor, a first insulator on the first transistor, a second conductor provided in an opening of the first insulator, a second transistor on the first insulator, and a third conductor on the second transistor. The first conductor functions as one of a source electrode and a drain electrode of the first transistor, the first semiconductor and the second conductor overlap each other, the second conductor and the third conductor overlap each other, the third conductor and the second transistor overlap each other, and the first semiconductor and the second transistor are electrically connected via the second conductor and the third conductor.

[0012] Also, in the above configuration, the third conductor is preferably electrically connected to a bump or wire bonding.

[0013] Also, in the above configuration, the third conductor is preferably an electrode pad in contact with a bump or wire bonding.

[0014] Also, in the above configuration, having a fourth conductor on the first semiconductor, the fourth conductor functions as one of a source electrode and a drain electrode of the second transistor, and the fourth conductor and the second conductor are preferably electrically connected.

[0015] Also, in the above configuration, the second transistor has a metal oxide, and the metal oxide preferably has indium.

[0016] Also, in the above configuration, the second transistor has a metal oxide, the metal oxide has indium, zinc, and element M, and element M is preferably one or more selected from aluminum, gallium, yttrium, tin, boron, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, and magnesium.

[0017] Also, in the above configuration, the first semiconductor preferably has one or more materials selected from silicon, silicon carbide, germanium, silicon germanium, gallium arsenide, gallium aluminum arsenide, indium phosphide, zinc selenide, gallium nitride, and gallium oxide.

[0018] Also, in the above configuration, it has a third transistor on the first conductor, the third transistor has a third semiconductor, the third semiconductor has the same material as one or more materials selected from silicon, silicon carbide, germanium, silicon germanium, gallium arsenide, gallium aluminum arsenide, indium phosphide, zinc selenide, gallium nitride, and gallium oxide that the first semiconductor has, and the first conductor preferably functions as the source or drain of the third transistor.

[0019] Alternatively, one aspect of the present invention preferably has the semiconductor device described in any of the above and a secondary battery, and the negative electrode of the secondary battery and the third conductor are electrically connected.

[0020] Alternatively, one aspect of the present invention has a first layer, a second layer, a first insulator disposed between the first layer and the second layer, and a first conductor. The first conductor is provided in a first opening of the first insulator. The first layer has a first transistor, the first transistor has a first semiconductor, and the first semiconductor is one or more selected from silicon, silicon carbide, germanium, silicon germanium, gallium arsenide, gallium aluminum arsenide, indium phosphide, zinc selenide, gallium nitride, and gallium oxide. The second layer has a comparator and a logic circuit. The logic circuit or the comparator has a second transistor. The first transistor is electrically connected to the second transistor via the first conductor. The comparator has a function of providing a signal corresponding to the positive electrode voltage of the secondary battery to the logic circuit, and the logic circuit has a function of providing a signal corresponding to the output from the comparator to the gate of the first transistor, which is a battery control circuit.

[0021] Also, in the above configuration, it is preferable that the first transistor and the second transistor overlap each other.

[0022] Also, in the above configuration, the second transistor preferably has a metal oxide, and the metal oxide preferably has indium.

[0023] Also, in the above configuration, the second transistor has a second semiconductor, the second semiconductor has a metal oxide, the metal oxide has indium, zinc, and element M, and element M is preferably one or more selected from aluminum, gallium, yttrium, tin, boron, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, and magnesium.

[0024] Also, in any one of the above configurations, the first conductor is preferably electrically connected to the negative electrode of the secondary battery.

[0025] Alternatively, one aspect of the present invention is an electronic component having a first chip having the battery control circuit described in any one of the above, a second chip having an integrated circuit, a printed circuit board, and bumps between the first chip and the printed circuit board. The integrated circuit has a function of supplying at least one of a control signal and power to the battery control circuit of the first chip. The first chip and the second chip are each disposed on the printed circuit board. The first chip has a first surface on which a first conductor is exposed, and the first surface and the printed circuit board are disposed so as to face each other via the bumps.

[0026] Alternatively, one aspect of the present invention is a vehicle having the above-described electronic component and an electric motor.

[0027] Alternatively, one aspect of the present invention is an electronic device having the above-described electronic component and a display unit. The electronic component has a third chip disposed on the printed circuit board, and the third chip has a function of transmitting and receiving signals by wireless communication.

Advantages of the Invention

[0028] According to one aspect of the present invention, a novel battery control circuit, battery protection circuit, power storage device, semiconductor device, vehicle, electronic device, etc. can be provided. Further, according to one aspect of the present invention, a battery control circuit, battery protection circuit, power storage device, semiconductor device, vehicle, electronic device, etc. with low power consumption can be provided. Further, according to one aspect of the present invention, a battery control circuit, battery protection circuit, power storage device, semiconductor device, vehicle, electronic device, etc. with high integration can be provided.

[0029] Note that the effects of one aspect of the present invention are not limited to the effects listed above. The effects listed above do not prevent the existence of other effects. Other effects are those effects not mentioned in this item as described below. Effects not mentioned in this item can be derived by those skilled in the art from the descriptions in the specification, drawings, etc., and can be appropriately extracted from these descriptions. Note that one aspect of the present invention has at least one of the effects listed above and / or other effects. Therefore, one aspect of the present invention may not have the effects listed above in some cases.

Brief Description of Drawings

[0030]

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Mode for Carrying Out the Invention

[0031] Hereinafter, embodiments will be described with reference to the drawings. However, the embodiments can be implemented in many different modes, and it will be easily understood by those skilled in the art that the forms and details can be variously changed without departing from the spirit and its scope. Therefore, the present invention is not construed as being limited to the description of the following embodiments.

[0032] In this specification and the like, ordinal numbers such as "first", "second", and "third" are attached to avoid confusion of components. Therefore, they do not limit the number of components. Also, they do not limit the order of components. For example, in one of the embodiments of this specification and the like, a component referred to as "first" may be a component referred to as "second" in other embodiments or in the claims. Also, for example, a component referred to as "first" in one of the embodiments of this specification and the like may be omitted in other embodiments or in the claims.

[0033] In the drawings, the same reference numerals may be given to the same elements, elements having the same or similar functions, elements of the same material, or elements formed simultaneously, and repeated descriptions thereof may be omitted.

[0034] Also, the position, size, range, etc. of each configuration shown in the drawings and the like may not represent the actual position, size, range, etc. in order to facilitate understanding of the invention. For this reason, the disclosed invention is not necessarily limited to the position, size, range, etc. disclosed in the drawings and the like. For example, in an actual manufacturing process, a resist mask or the like may be unintentionally reduced in size due to a process such as etching, but this may not be reflected in the drawing for ease of understanding.

[0035] Also, in a top view (also referred to as a "plan view") or a perspective view, etc., in order to make the drawing easier to understand, the description of some components may be omitted.

[0036] Also, in this specification and the like, the terms "electrode" and "wiring" do not functionally limit these components. For example, an "electrode" may be used as part of a "wiring", and vice versa. Furthermore, the terms "electrode" and "wiring" also include cases where a plurality of "electrodes" and "wirings" are integrally formed.

[0037] In addition, in this specification and the like, the term "terminal" may refer to, for example, a wiring or an electrode connected to the wiring. Also, in this specification and the like, a part of the "wiring" may be referred to as a "terminal".

[0038] Note that in this specification and the like, the terms "above" and "below" do not limit the positional relationship of the components to be directly above or directly below and in direct contact. For example, in the expression "electrode B on insulating layer A", it is not necessary for electrode B to be formed directly in contact on insulating layer A, and those including other components between insulating layer A and electrode B are not excluded.

[0039] Also, since the functions of the source and drain are interchanged depending on operating conditions such as when transistors of different polarities are employed or when the direction of current changes in circuit operation, it is difficult to limit which one is the source or drain. For this reason, in this specification, the terms source and drain can be used interchangeably.

[0040] In addition, in this specification and the like, "electrically connected" includes both the case of direct connection and the case of being connected via "something having some electrical action". Here, "something having some electrical action" is not particularly limited as long as it enables the transfer of electrical signals between the connection targets. Therefore, even when expressed as "electrically connect", in an actual circuit, there may be a case where there is no physical connection part and only the wiring extends.

[0041] In addition, in this specification and the like, "parallel" means, for example, a state in which two straight lines are arranged at an angle of -10° or more and 10° or less. Therefore, the case of -5° or more and 5° or less is also included. Also, "perpendicular" and "orthogonal" mean, for example, a state in which two straight lines are arranged at an angle of 80° or more and 100° or less. Therefore, the case of 85° or more and 95° or less is also included.

[0042] In addition, in this specification and the like, when referring to count values and measured values as "identical", "the same", "equal", or "uniform", etc., unless otherwise specified, they shall be deemed to include an error of plus or minus 20%.

[0043] Also, in this specification, when an etching process is performed after forming a resist mask, unless otherwise specified, the resist mask shall be removed after the etching process is completed.

[0044] Also, voltage often indicates the potential difference between a certain potential and a reference potential (such as ground potential or source potential). Therefore, voltage and potential can often be used interchangeably.

[0045] Note that even when denoted as "semiconductor", for example, when the conductivity is sufficiently low, it has the characteristics of an "insulator". Therefore, it is also possible to use "insulator" instead of "semiconductor". In this case, the boundary between "semiconductor" and "insulator" is ambiguous, and it is difficult to strictly distinguish between the two. Therefore, the "semiconductor" and "insulator" described in this specification may be able to be read as each other in some cases.

[0046] Also, even when denoted as "semiconductor", for example, when the conductivity is sufficiently high, it has the characteristics of a "conductor". Therefore, it is also possible to use "conductor" instead of "semiconductor". In this case, the boundary between "semiconductor" and "conductor" is ambiguous, and it is difficult to strictly distinguish between the two. Therefore, the "semiconductor" and "conductor" described in this specification may be able to be read as each other in some cases.

[0047] Note that in this specification and the like, the "on state" of a transistor refers to a state in which the source and drain of the transistor can be regarded as being electrically short-circuited (also referred to as the "conducting state"). Also, the "off state" of a transistor refers to a state in which the source and drain of the transistor can be regarded as being electrically disconnected (also referred to as the "non-conducting state").

[0048] In addition, in this specification and the like, the "on-current" may refer to the current flowing between the source and the drain when the transistor is in the on-state. Also, the "off-current" may refer to the current flowing between the source and the drain when the transistor is in the off-state.

[0049] In addition, in this specification and the like, the high power supply potential VDD (hereinafter, also simply referred to as "VDD" or "H potential") indicates a power supply potential having a potential higher than the low power supply potential VSS. Also, the low power supply potential VSS (hereinafter, also simply referred to as "VSS" or "L potential") indicates a power supply potential having a potential lower than the high power supply potential VDD. Also, the ground potential can be used as VDD or VSS. For example, when VDD is the ground potential, VSS is a potential lower than the ground potential, and when VSS is the ground potential, VDD is a potential higher than the ground potential.

[0050] In addition, in this specification and the like, the "gate" refers to part or all of the gate electrode and the gate wiring. The "gate wiring" refers to the wiring for electrically connecting the gate electrode of at least one transistor to another electrode or another wiring.

[0051] In addition, in this specification and the like, the "source" refers to part or all of the source region, the source electrode, and the source wiring. The "source region" refers to a region in the semiconductor layer having a resistivity equal to or less than a certain value. The "source electrode" refers to the conductive layer connected to the source region. The "source wiring" refers to the wiring for electrically connecting the source electrode of at least one transistor to another electrode or another wiring.

[0052] In addition, in this specification and the like, the "drain" refers to part or all of the drain region, the drain electrode, and the drain wiring. The "drain region" refers to a region in the semiconductor layer having a resistivity equal to or less than a certain value. The "drain electrode" refers to the conductive layer connected to the drain region. The "drain wiring" refers to the wiring for electrically connecting the drain electrode of at least one transistor to another electrode or another wiring.

[0053] (Embodiment 1) In this embodiment, the configuration of a battery control circuit and a power storage device including the battery control circuit will be described.

[0054] The battery control circuit according to one aspect of the present invention, or a power storage device including the battery control circuit, may be referred to as "BTOS". "BTOS" may be able to construct a system with low power consumption. "BTOS" may be able to construct a system with a simple circuit.

[0055] The battery control circuit according to one aspect of the present invention has a function of controlling a battery. For example, it has a function of switching modes. For example, it has a function of changing the charging or discharging conditions of the battery. Examples of the mode include a constant current mode, a constant voltage mode, etc. The conditions include, for example, current density, upper limit voltage, lower limit voltage, etc. Further, the battery control circuit according to one aspect of the present invention preferably has a function of protecting the battery. For example, it has a function of stopping the charging or discharging of the battery. For example, it has a function of discharging the battery in response to detection of overcharging. For example, it has a function of detecting an abnormality of the battery and stopping the operation of the battery or changing the conditions of the battery. Stopping the operation of the battery includes, for example, stopping charging or discharging. Examples of the abnormality of the battery include overcharging, over-discharging, overcurrent during charging, overcurrent during discharging, short circuit, micro short circuit described later, deviation from a predetermined range of operating temperature, etc. Further, the battery control circuit according to one aspect of the present invention may be called a battery protection circuit.

[0056] <An example 1 of a power storage device> FIG. 1 shows an example of a power storage device 100. The power storage device 100 shown in FIG. 1 has a battery control circuit 101 and a battery pack 120. It is preferable that a circuit using a transistor having an oxide semiconductor in a channel formation region (hereinafter referred to as an OS transistor) is mounted on the battery control circuit 101.

[0057] The battery control circuit 101 has a circuit 101a and a circuit 101b.

[0058] The circuit 101a includes a cell balance circuit 130, a detection circuit 185, a detection circuit 186, a detection circuit MSD, a detection circuit SD, a temperature sensor TS, and a logic circuit 182.

[0059] Further, the circuit 101b includes a transistor 140 and a transistor 150. As the transistor 140 and the transistor 150, various transistors described in this specification and the like can be used, for example, the transistors shown in the following embodiments. As shown in FIG. 1, it is preferable that the transistor 140 and the transistor 150 each have a parasitic diode.

[0060] An OS transistor can be used as the transistors included in the cell balance circuit 130, the detection circuit 185, the detection circuit 186, the detection circuit MSD, the detection circuit SD, the temperature sensor TS, and the logic circuit 182 included in the circuit 101a.

[0061] As an example of the transistor 140 and the transistor 150 included in the circuit 101b, consider an example in which a transistor having single-crystalline silicon in a channel formation region is used. In such a case, for example, the transistor 140 and the transistor 150 can be formed on a silicon substrate, and an OS transistor can be formed thereon using a film formation process, and the circuit 101a and the circuit 101b can be formed on the same substrate. Thereby, for example, cost reduction can be achieved. Also, integration of the circuit becomes possible, and the circuit area can be reduced. Further, by providing the circuit 101a and the circuit 101b laminated on the same substrate, the resistance of the wiring routing can be reduced. A large current may flow through the transistor 140 and the transistor 150, and it is preferable to reduce the wiring resistance.

[0062] The battery pack 120 has a plurality of battery cells 121. In FIG. 1, an example having n battery cells 121 is shown. The k-th battery cell (k is an integer from 1 to n) may be represented as battery cell 121(k). The plurality of battery cells included in the battery pack 120 are electrically connected in series. Here, FIG. 1 shows an example in which the battery pack 120 has a plurality of battery cells 121 connected in series, but the battery pack 120 may have only one battery. Alternatively, the battery pack 120 may have a plurality of batteries, and the plurality of batteries may be connected in parallel in multiple numbers.

[0063] Here, for example, a secondary battery shown in the following embodiments can be used as the battery cell. For example, a secondary battery having a wound battery element can be used. Also, the battery cell preferably has an exterior body. For example, a cylindrical exterior body, a rectangular exterior body, or the like can be used. As the material of the exterior body, a metal plate covered with an insulator, a metal film sandwiched between insulators, or the like can be used. The battery cell has, for example, a pair of positive and negative electrodes. Also, the battery cell may have a terminal electrically connected to the positive electrode and a terminal electrically connected to the negative electrode. Also, the battery cell may be part of the battery control circuit of one aspect of the present invention.

[0064] The cell balance circuit 130 has a function of controlling the charging of the individual battery cells 121 included in the battery pack 120. The detection circuit 185 has a function of detecting overcharging and over-discharging of the battery pack 120. The detection circuit 186 has a function of detecting discharge overcurrent and charge overcurrent of the battery pack 120.

[0065] The detection circuit MSD has a function of detecting a micro short circuit.

[0066] A micro short circuit refers to a minute short circuit inside a secondary battery. It does not mean that the positive and negative electrodes of the secondary battery are short-circuited to a state where charge and discharge are impossible, but rather refers to a phenomenon where a short-circuit current flows for a short period at a minute short-circuit portion. The cause of the micro short circuit is presumed to be that when charge and discharge are performed multiple times, metal elements such as lithium or cobalt are deposited inside the battery, and as the deposits grow, local current concentration occurs between a part of the positive electrode and a part of the negative electrode, resulting in a location where a part of the separator ceases to function, or the generation of side reaction products.

[0067] The detection circuit SD detects, for example, a short circuit in a circuit that operates using the battery pack 120. Also, the detection circuit SD detects, for example, the charging current and the discharging current of the battery pack 120.

[0068] The battery control circuit 101 has terminals VC1 to VCN that are electrically connected to the positive electrodes of each of the n battery cells 121 included in the battery pack 120, and a terminal VSSS that is electrically connected to the negative electrode of the Nth battery cell 121.

[0069] Also, the battery control circuit 101 has a terminal group AH. The terminal group AH has one terminal or a plurality of terminals.

[0070] The terminal group AH preferably has a function of supplying a signal to the logic circuit 182 and a function of supplying a signal from the logic circuit 182 to a circuit provided outside the battery control circuit 101.

[0071] Logic circuit 182 has a function of controlling transistors 140 and 150 according to output signals from detection circuit 185, detection circuit 186, detection circuit SD, detection circuit MSD, and temperature sensor TS. Further, logic circuit 182 may supply a signal to a charging circuit provided outside or inside battery control circuit 101. In this case, for example, charging of the secondary battery is controlled according to a signal supplied from logic circuit 182 to the charging circuit. Here, the charging circuit has, for example, a function of controlling the charging conditions of the battery. Alternatively, a signal for controlling the charging conditions of the battery is supplied to another circuit, for example, a cell balance circuit, an overcharge detection circuit, transistors 140 and 150, a circuit for controlling transistors 140 and 150, etc. included in one aspect of the present invention.

[0072] Transistors 140 and 150 have a function of controlling charging or discharging of battery pack 120. As an example, the conduction state or non-conduction state of transistor 140 is controlled by control signal T1 supplied by logic circuit 182, and whether to charge battery pack 120 is controlled. Also, the conduction state or non-conduction state of transistor 150 is controlled by control signal T2 supplied by logic circuit 182, and whether to discharge battery pack 120 is controlled. Also, in the example shown in FIG. 1, one of the source and drain of transistor 140 is electrically connected to terminal VSSS. The other of the source and drain of transistor 140 is electrically connected to one of the source and drain of transistor 150. The other of the source and drain of transistor 150 is electrically connected to terminal VM. Terminal VM is electrically connected to, for example, the negative electrode of the charger. Also, terminal VM is electrically connected to, for example, the load during discharging.

[0073] The battery control circuit 101 may have a function of observing the voltage values (monitoring voltages) of each terminal of the battery cells 121 included in the assembled battery 120 and the current value (monitoring current) flowing through the assembled battery. For example, it may be configured to observe the on-current of the transistor 140 or the transistor 150 as the monitoring current. Alternatively, a resistance element may be provided in series with the transistor 140 or the like, and the current value of the resistance element may be observed.

[0074] The temperature sensor TS may have a function of measuring the temperature of the battery cell 121 and controlling the charging and discharging of the battery cell based on the measured temperature. For example, at a low temperature, the resistance of the secondary battery may increase, so the charging current density and the discharging current density may be decreased. Also, at a high temperature, the resistance of the secondary battery may decrease, so the discharging current density may be increased. Further, when there is a concern about deterioration of the secondary battery characteristics due to increasing the charging current at a high temperature, for example, the charging current may be controlled to a value at which the deterioration is suppressed. Data such as charging conditions and discharging conditions are preferably stored in a storage circuit or the like included in the battery control circuit 101 according to one aspect of the present invention. Also, the temperature of the battery control circuit 101 or the assembled battery 120 may increase due to charging. In such a case, it is preferable to control the charging according to the measured temperature. For example, the charging current may be suppressed as the temperature increases.

[0075] As the memory element, the configuration of the memory element 114 shown in FIG. 2A can be used. The memory element 114 shown in FIG. 2A includes a capacitance element 161 and a transistor 162.

[0076] As the transistor 162, it is preferable to use an OS transistor. In the configuration according to one aspect of the present invention, by adopting a configuration using the memory element 114 having an OS transistor, a desired voltage can be held in the memory element by taking advantage of the fact that the leakage current (hereinafter, off-current) flowing between the source and the drain during the off state is extremely low.

[0077] FIG. 2B is different from FIG. 2A in that the transistor 162 included in the memory element 114 has a second gate. The second gate may be called a back gate or a bottom gate. The second gate included in the OS transistor will be described in detail in a later embodiment.

[0078] Next, the components of the cell balance circuit 130 and the detection circuit 185 will be described.

[0079] FIG. 3 shows a cell balance circuit 130a and a detection circuit 185a corresponding to one battery cell 121.

[0080] The cell balance circuit 130 shown in FIG. 1 includes a plurality of cell balance circuits 130a, and each cell balance circuit 130a is connected to one battery cell. In a configuration where a plurality of battery cells 121 are connected in series, a cell balance circuit 130a and a transistor 132 are provided for each battery cell 121, and by directly connecting the transistor 132, when charging the plurality of battery cells 121 connected in series, the variation in the charging voltage between the battery cells 121 can be reduced.

[0081] The detection circuit 185a shown in FIG. 3 includes a circuit 185c and a circuit 185d. The detection circuit 185 has a function of detecting overcharge, and the detection circuit 186 has a function of detecting over-discharge.

[0082] The detection circuit 185 shown in FIG. 1 includes a plurality of detection circuits 185a, and each detection circuit 185a is connected to one battery cell. Alternatively, for a configuration in which a plurality of battery cells 121 are connected in series, one detection circuit 185a may be provided.

[0083] In FIG. 3, the transistor 132 and the resistance element 131 are connected in series, and one of the source and drain of the transistor 132 is electrically connected to the negative electrode of the battery cell 121, and the other is electrically connected to one electrode of the resistance element. The other electrode of the resistance element is electrically connected to the positive electrode of the secondary battery.

[0084] Here, one of the source and drain of the transistor 132 may be electrically connected to the positive electrode of the battery cell 121, the other may be electrically connected to one electrode of the resistance element 131, and the other electrode of the resistance element 131 may be electrically connected to the negative electrode of the battery cell 121, respectively.

[0085] Also, in FIG. 3, the cell balance circuit 130a, the circuit 185c, and the circuit 185d each have a comparator 113 and a memory element 114. The memory element 114 has a capacitor element 161 and a transistor 162. The memory element 114 is electrically connected to one of the non-inverting input terminal or the inverting input terminal of each comparator 113 included in the cell balance circuit 130a, the circuit 185c, and the circuit 185d. In the memory element 114, a common terminal, here the terminal VT, is electrically connected to one of the source and drain of the transistor 162 included in each memory element 114. Also, in the memory element 114, a terminal (terminal SH6 in the cell balance circuit 130a, terminal SH1 in the circuit 185c, and terminal SH2 in the circuit 185d) is electrically connected to the gate of the transistor 162 included in each memory element 114.

[0086] In FIG. 3, the cell balance circuit 130a is electrically connected to the positive electrode and the negative electrode of the battery cell 121. The positive electrode of the battery cell 121 is electrically connected to the terminal VC1, and the negative electrode is electrically connected to the terminal VC2. In the cell balance circuit 130a, the inverting input terminal of the comparator 113 is electrically connected to the other of the source and drain of the transistor 162 included in the memory element 114. Also, in the cell balance circuit 130a, it is preferable that the non-inverting input terminal of the comparator 113 is electrically connected to the terminal VC1. Alternatively, as shown in FIG. 3, a voltage obtained by resistively dividing the voltage between the terminal VC1 and the terminal VC2 may be applied to the non-inverting input terminal of the comparator 113. In the cell balance circuit 130a, the node connected to the other of the source and drain of the transistor 162 included in the memory element 114 is defined as the node N6.

[0087] In FIG. 3, the detection circuit 185a is electrically connected to the positive and negative electrodes of the battery cell 121. In the circuit 185c, the inverting input terminal of the comparator is electrically connected to the other of the source and drain of the transistor 162. Also in the circuit 185c, the non-inverting input terminal of the comparator 113 is preferably electrically connected to the terminal VC1. Alternatively, as shown in FIG. 3, a voltage obtained by resistively dividing the voltage between the terminals VC1 and VC2 may be applied to the non-inverting input terminal of the comparator 113. In the circuit 185c, the node connected to the other of the source and drain of the transistor 162 is defined as the node N1.

[0088] In the circuit 185d, the non-inverting input terminal of the comparator is electrically connected to the other of the source and drain of the transistor 162. Also in the circuit 185d, the inverting input terminal of the comparator 113 is preferably electrically connected to the terminal VC1. Alternatively, as shown in FIG. 3, a voltage obtained by resistively dividing the voltage between the terminals VC1 and VC2 may be applied to the inverting input terminal of the comparator 113. In the circuit 185d, the node connected to the other of the source and drain of the transistor 162 is defined as the node N2.

[0089] In the cell balance circuit 130 and the detection circuit 185, the potential is held at the nodes (here, the nodes N6, N1, and N2) to which the other electrodes of the capacitive elements 161 included in the respective circuits are connected, by turning off the transistor 162.

[0090] Terminal VT sequentially supplies an analog signal to the cell balance circuit 130, circuit 185c, and circuit 185d. An analog signal is sequentially supplied to and held at node N6, node N1, and node N2. Among node N6, node N1, and node N2, after an analog signal is supplied to the first node, the potential of the first node is held by turning off transistor 162 connected to the node. Thereafter, a potential is supplied to and held at the second node, and then a potential is supplied to and held at the third node. The on and off control of transistor 162 is controlled by signals supplied to terminal SH1, terminal SH2, and terminal SH6.

[0091] By providing the cell balance circuit 130 and the detection circuit 185 shown in FIG. 3 for each of the battery cells 121 included in the battery pack 120, the voltage difference (the difference between the voltage of the positive electrode and the negative electrode) at both ends of each of the plurality of battery cells 121 can be individually controlled. Further, the cell balance circuit 130 can cause the storage element 114 to hold a preferable value as the first upper limit voltage of the positive electrode for each battery cell 121.

[0092] The cell balance circuit 130 controls whether to turn on or off transistor 132 according to the relationship between the voltage of the positive electrode of the battery cell 121 and the voltage of the non-inverting input terminal of the comparator 113. By controlling transistor 132, the ratio between the current flowing through the resistance element 131 and the current flowing through the battery cell 121 can be adjusted. For example, when stopping the charging of the battery cell 121, a current is passed through the resistance element 131 to limit the current flowing through the battery cell 121.

[0093] In FIG. 1, a plurality of battery cells 121 are electrically connected in series between terminal VC1 and terminal VSSS. The plurality of battery cells 121 are charged by passing a current between terminal VC1 and terminal VSSS.

[0094] Consider a case where, in one of the plurality of battery cells 121, the positive electrode reaches a predetermined voltage and the current is limited. In such a case, by passing a current through the transistor 132 and the resistance element 131 connected in parallel to the battery cell, the charging of the other battery cells 121 whose positive electrodes have not reached the predetermined voltage can be continued without interrupting the current path between the terminal VC1 and the terminal VSSS. That is, in the battery cell 121 in which charging is completed, charging is stopped by turning on the transistor 132, and in the battery cell 121 in which charging is not completed, charging is continued with the transistor 132 turned off.

[0095] If there is, for example, a variation in resistance for each battery cell 121, the charging of a battery cell 121 with a low resistance may be completed first, and the charging of a battery cell 121 with a higher resistance may be insufficient compared to a certain battery cell 121. Here, insufficient charging means, for example, that the voltage difference between the positive electrode and the negative electrode is lower than the desired voltage. By using the cell balance circuit 130, the voltage of the positive electrode of the battery cell 121 during charging can be controlled based on the voltage of the negative electrode of each battery cell.

[0096] In the cell balance circuit according to one aspect of the present invention, without using a circuit provided outside the battery control circuit 101, such as an arithmetic circuit such as an MPU or an MCU, the charging voltage, the charging capacity, etc. of one battery cell or a plurality of battery cells can be controlled.

[0097] That is, by using n cell balance circuits 130, the variation in the state after charging of the plurality of battery cells 121, for example, the variation at full charge, can be reduced. Therefore, the capacity of the assembled battery 120 as a whole may increase. In addition, by increasing the capacity, the number of charge and discharge cycles of the battery cell 121 may be reduced, so the durability of the assembled battery 120 may increase.

[0098] Circuit 185c can cause the storage element 114 to hold the second upper limit voltage of the positive electrode in the charging of the battery cell 121 for each battery cell 121. This second upper limit voltage may be referred to as the overcharge voltage. Circuit 185d can cause the storage element 114 to hold the lower limit voltage of the positive electrode in the discharge. This lower limit voltage may be referred to as the overdischarge voltage.

[0099] Note that the comparator constituting the detection circuit 185 may be a hysteresis comparator, i.e., the threshold value is different when the output changes from the L level to the H level and when the output changes from the H level to the L level. It is preferable that the storage element connected to the input part of the reference potential of the hysteresis comparator has a function of holding two threshold values.

[0100] In the detection circuit 185, without using a circuit provided outside the battery control circuit 101, such as an arithmetic circuit like an MPU or an MCU, overcharge and overdischarge of one battery cell or a plurality of battery cells can be detected, and the battery cells can be protected. When a voltage drop due to overdischarge is detected, the control circuit according to one aspect of the present invention cuts off the discharge current to prevent the voltage drop. If the cutoff of the discharge current is insufficient, a leakage current may occur, and a voltage drop may occur. With a circuit configuration using power gating, the leakage current may be suppressed. Also, with a circuit configuration using an OS transistor, the leakage current may be suppressed.

[0101] The upper limit voltages of the cell balance circuit connected to the battery cell and the circuit for detecting overcharge are each controlled. The upper limit voltage detected by the cell balance circuit is, for example, lower than the upper limit voltage detected by the circuit for detecting overcharge. Therefore, in the process of charging, the cell balance circuit detects the reach of the upper limit voltage of the battery cell in the first step and changes the charging conditions. Here, for example, the current density of charging is reduced. Alternatively, discharging may be started. Thereafter, when it is detected that the upper limit voltage detected by the overcharge detection circuit is reached as the charging voltage of the battery cell increases, the charging conditions of the battery cell are changed in the second step. Here, for example, charging is stopped and discharging is started.

[0102] <Further components of the power storage device> An example of a further component included in the power storage device according to one aspect of the present invention will be described below.

[0103] FIG. 4 shows an example of the logic circuit 182. The logic circuit 182 shown in FIG. 4 includes an interface circuit IF, a counter circuit CND, a latch circuit LTC, and a transistor 172. It is preferable to use an OS transistor as the transistor 172. Note that the configuration shown in FIG. 4 may be composed only of the OS transistors included in the battery control circuit according to one aspect of the present invention, or only a part of the configuration shown in FIG. 4 may be composed of the OS transistors included in the battery control circuit according to one aspect of the present invention. When only a part of the configuration shown in FIG. 4 is composed of the OS transistors included in the battery control circuit according to one aspect of the present invention, the other part is composed of, for example, a transistor having single crystal silicon.

[0104] The interface circuit IF is supplied with signals from the output terminal OUT11 and the output terminal OUT12 of the detection circuit 185, signals from the output terminal OUT31 and the output terminal OUT32 of the detection circuit 186, and a signal from the output terminal OUT41 of the detection circuit SD. The output terminal OUT11 gives, for example, a signal corresponding to overcharge. The output terminal OUT12 gives, for example, a signal corresponding to overdischarge. The output terminal OUT31 gives, for example, a signal corresponding to overcurrent during charging. The output terminal OUT32 gives, for example, a signal corresponding to overcurrent during discharging.

[0105] When the interface circuit IF detects a signal indicating an abnormality, for example, a signal corresponding to at least one of overcharge, overdischarge, and overcurrent, it supplies the signal PG to the gate of the transistor 172.

[0106] The transistor 172 is connected to the counter circuit CND.

[0107] When the signal PG is a signal that turns on the transistor 172, more specifically, for example, when it outputs a high-potential signal, the counter circuit CND operates a counter and a delay circuit. On the other hand, when the signal PG is a signal that turns off the transistor 172, more specifically, for example, when it outputs a low-potential signal, the operation of the counter circuit CND can be stopped or the counter circuit CND can be put into a standby state. A signal res is supplied from the interface circuit IF to the counter circuit CND and the latch circuit LTC. The signal res is a reset signal. When the signal res is supplied to the counter circuit CND, counting starts. The signal en is an enable signal. The counter circuit CND starts or stops its operation according to the signal en.

[0108] When a signal indicating an abnormality is supplied to the interface circuit IF, after the counter circuit CND counts for a certain period, the signal corresponding to the detected abnormality is supplied to the latch circuit LTC via the counter circuit CND.

[0109] The latch circuit LTC supplies a signal that turns off the transistor to the gate of transistor 140 or transistor 150 in response to the detected abnormality.

[0110] FIG. 5A shows an example of the circuit diagram of the detection circuit 186. The detection circuit 186 has two comparators 113.

[0111] A memory element 114 that holds a voltage corresponding to the discharge overcurrent detection is electrically connected to the non-inverting input terminal of one comparator 113. A terminal SH3 is electrically connected to the gate of the transistor included in the memory element 114. Also, a terminal SENS is electrically connected to the inverting input terminal. When an overcurrent is detected by the voltage applied to the inverting input terminal, the output from the output terminal OUT32 is inverted.

[0112] A terminal SENS is electrically connected to the non-inverting input terminal of the other comparator 113. Also, a memory element 114 corresponding to the charge overcurrent detection is electrically connected to the inverting input terminal. A terminal SH4 is electrically connected to the gate of the transistor included in the memory element 114. When an overcurrent is detected by the voltage applied to the non-inverting input terminal, the output from the output terminal OUT31 is inverted.

[0113] The temperature sensor TS has a function of measuring the temperature of the battery pack 120 or the power storage device 100 including the battery pack 120. FIG. 5B is a circuit diagram showing an example of the temperature sensor TS. Note that the circuit diagram shown in FIG. 5B may represent a part of the circuit of the temperature sensor TS.

[0114] In FIG. 5B, the temperature sensor TS has three comparators 113, and voltages VT (VT = Tm1, Tm2, Tm3) corresponding to different temperatures are respectively applied to the inverting input terminals of the respective comparators. Each of the applied voltages VT is held by a memory element 114 electrically connected to the inverting input terminal. The voltages Tm1, Tm2, and Tm3 may be supplied from, for example, a voltage generation circuit 119.

[0115] A voltage corresponding to the measured temperature is applied to the input terminal Vt. The input terminal Vt is applied to the non-inverting input terminal of each of the three comparators 113.

[0116] Corresponding to the comparison result between the voltage applied to the input terminal Vt and the voltage of the inverting input terminal of each comparator 113, signals are output from the output terminals (output terminal OUT51, output terminal OUT52, output terminal OUT53) of each comparator, and the temperature can be determined.

[0117] The OS transistor has the property that its resistance value decreases as the temperature rises. By utilizing this property, the ambient temperature can be converted into a voltage. This voltage can be applied to the input terminal Vt, for example.

[0118] The logic circuit 182 may be configured to detect the output of the temperature sensor TS and turn off the transistor 140 and / or the transistor 150 to stop charging and / or discharging when the operable temperature range of the battery pack 120 is exceeded.

[0119] <Battery cell> A lithium-ion secondary battery cell can be used as the battery cell 121. The positive electrode active material of the lithium-ion secondary battery cell preferably has a metal (hereinafter, element A) that becomes a carrier ion. As element A, for example, alkali metals such as lithium, sodium, and potassium, and Group 2 elements such as calcium, beryllium, and magnesium can be used.

[0120] In the positive electrode active material, carrier ions are desorbed from the positive electrode active material during charging. If a large amount of element A is desorbed, there are many ions contributing to the capacity of the secondary battery, and the capacity increases. On the other hand, if a large amount of element A is desorbed, the crystal structure of the compound contained in the positive electrode active material is likely to collapse. The collapse of the crystal structure of the positive electrode active material may cause a decrease in the discharge capacity associated with the charge-discharge cycle. When the positive electrode active material according to one aspect of the present invention contains element X, the collapse of the crystal structure when carrier ions are desorbed during charging of the secondary battery may be suppressed. For example, a part of element X is substituted at the position of element A. As element X, elements such as magnesium, calcium, zirconium, lanthanum, and barium can be used. Also, for example, elements such as copper, potassium, sodium, and zinc can be used as element X. Further, two or more of the elements shown above may be used in combination as element X.

[0121] Further, the positive electrode active material preferably contains a halogen in addition to element X. It is preferable to contain a halogen such as fluorine or chlorine. When the positive electrode active material contains the halogen, the substitution of element X at the position of element A may be promoted.

[0122] When the positive electrode active material contains element X, or when it contains a halogen in addition to element X, the electrical conductivity on the surface of the positive electrode active material may be suppressed.

[0123] Further, the positive electrode active material contains a metal (hereinafter, element M) whose valence changes by charging and discharging of the secondary battery. Element M is, for example, a transition metal. The positive electrode active material has, for example, one or more of cobalt, nickel, and manganese as element M, and particularly has cobalt. Further, at the position of element M, an element that does not change in valence and can have the same valence as element M, such as aluminum, more specifically, for example, a trivalent typical element may be contained. The aforementioned element X may be substituted at the position of element M, for example. Also, when the positive electrode active material is an oxide, element X may be substituted at the position of oxygen.

[0124] As the positive electrode active material, it is preferable to use, for example, a lithium composite oxide having a layered rock salt type crystal structure. More specifically, for example, as the lithium composite oxide having a layered rock salt type crystal structure, lithium cobalt oxide, lithium nickel oxide, a lithium composite oxide having nickel, manganese and cobalt, a lithium composite oxide having nickel, cobalt and aluminum, etc. can be used. Further, these positive electrode active materials are preferably represented by the space group R-3m.

[0125] In the positive electrode active material having a layered rock salt type crystal structure, when the depth of charge is increased, the crystal structure may collapse. Here, the collapse of the crystal structure is, for example, the displacement of the layers. When the collapse of the crystal structure is irreversible, the capacity of the secondary battery may decrease with repeated charge and discharge.

[0126] When the positive electrode active material contains element X, for example, even when the depth of charge becomes deep, the above-mentioned layer displacement is suppressed. By suppressing the displacement, the volume change during charge and discharge can be reduced. Therefore, the positive electrode active material can achieve excellent cycle characteristics. Further, the positive electrode active material can have a stable crystal structure in a charged state at a high voltage. Therefore, when the positive electrode active material maintains a charged state at a high voltage, a short circuit may be less likely to occur. In such a case, since the safety is further improved, it is preferable.

[0127] In the positive electrode active material, the change in the crystal structure and the volume difference per the same number of transition metal atoms in a fully discharged state and a state charged at a high voltage are small.

[0128] The positive electrode active material may be represented by the chemical formula AM y O Z (y>0, z>0). For example, lithium cobalt oxide may be represented by LiCoO 2 . Also, for example, lithium nickel oxide may be represented by LiNiO 2 .

[0129] In the positive electrode active material having element X, when the depth of charge is 0.8 or more, although it is not represented by the space group R-3m and does not have a spinel-type crystal structure, ions such as element M (for example, cobalt) and element X (for example, magnesium) occupy the oxygen six-coordination positions, and the arrangement of cations may have symmetry similar to that of the spinel type. This structure is referred to as a pseudo-spinel-type crystal structure in this specification and the like. Note that in the pseudo-spinel-type crystal structure, light elements such as lithium may occupy the oxygen four-coordination positions, and in this case as well, the arrangement of ions has symmetry similar to that of the spinel type.

[0130] Due to the desorption of carrier ions accompanying charging, the structure of the positive electrode active material becomes unstable. It can be said that the pseudo-spinel-type crystal structure is a structure that can maintain high stability even though carrier ions have desorbed.

[0131] When the depth of charge is high, by using a positive electrode active material having a pseudo-spinel-type structure in a secondary battery, charging is possible even at a high charging voltage. For example, the battery control circuit according to one aspect of the present invention can freely change the set voltages used for cell balancing, overcharge detection, overdischarge detection, etc. according to the characteristics of the positive electrode active material by using the storage element 114. Therefore, for example, in the case of a positive electrode active material having a high charging voltage and excellent characteristics, the excellent characteristics can be fully exhibited while maintaining safety.

[0132] Also, although the pseudo-spinel-type crystal structure has Li randomly between layers, it can also be said that it is a crystal structure similar to the CdCl 2 type crystal structure. This crystal structure similar to the CdCl 2 type is close to the crystal structure of lithium nickel oxide when charged to a depth of charge of 0.94 (Li 0.06 NiO 2 ), but it is known that pure lithium cobaltate or a layered rock salt-type positive electrode active material containing a large amount of cobalt usually does not take this crystal structure.

[0133] In layered rock-salt type crystals and rock-salt type crystals, the anions take a cubic close-packed structure (face-centered cubic lattice structure). It is presumed that in pseudo-spinel type crystals, the anions also take a cubic close-packed structure. When these are in contact, there is a crystal plane where the orientations of the cubic close-packed structures composed of anions are aligned. However, since the space groups of layered rock-salt type crystals and pseudo-spinel type crystals are R-3m, which is different from the space groups of rock-salt type crystals, Fm-3m (the space group of a general rock-salt type crystal) and Fd-3m (the space group of a rock-salt type crystal with the simplest symmetry), the Miller indices of the crystal planes satisfying the above conditions are different between layered rock-salt type crystals and pseudo-spinel type crystals and rock-salt type crystals. In this specification, in layered rock-salt type crystals, pseudo-spinel type crystals, and rock-salt type crystals, when the orientations of the cubic close-packed structures composed of anions are aligned, it may be said that the crystal orientations are approximately the same.

[0134] The crystal structure of the pseudo-spinel type can show the coordinates of cobalt and oxygen in the unit cell within the range of Co(0,0,0.5), O(0,0,x), and 0.20 ≤ x ≤ 0.25.

[0135] In the positive electrode active material, the difference between the volume of the unit cell at a charge depth of 0 and the volume per unit cell of the pseudo-spinel type crystal structure at a charge depth of 0.82 is preferably 2.5% or less, and more preferably 2.2% or less.

[0136] In the pseudo-spinel type crystal structure, diffraction peaks appear at 2θ = 19.30 ± 0.20° (19.10° or more and 19.50° or less) and 2θ = 45.55 ± 0.10° (45.45° or more and 45.65° or less). More specifically, sharp diffraction peaks appear at 2θ = 19.30 ± 0.10° (19.20° or more and 19.40° or less) and 2θ = 45.55 ± 0.05° (45.50° or more and 45.60° or less).

[0137] The cathode active material has a pseudo-spinel crystal structure when charged at a high voltage, but not all of the particles need to have a pseudo-spinel crystal structure. It may contain other crystal structures or a part thereof may be amorphous. However, when Rietveld analysis is performed on the XRD pattern, the pseudo-spinel crystal structure is preferably 50 wt% or more, more preferably 60 wt% or more, and even more preferably 66 wt% or more. If the pseudo-spinel crystal structure is 50 wt% or more, more preferably 60 wt% or more, and even more preferably 66 wt% or more, a cathode active material with excellent cycle characteristics can be obtained.

[0138] The number of atoms of element X is preferably 0.001 times or more and 0.1 times or less, more preferably more than 0.01 and less than 0.04, and even more preferably about 0.02, based on the number of atoms of element M. The concentration of element X shown here may be, for example, a value obtained by performing elemental analysis on the entire particles of the cathode active material using ICP-MS or the like, or may be based on the value of the raw material formulation in the process of producing the cathode active material.

[0139] When the element M includes cobalt and nickel, the ratio Ni / (Co + Ni) of the number of atoms of nickel (Ni) to the sum of the number of atoms of cobalt and nickel (Co + Ni) is preferably less than 0.1, and more preferably 0.075 or less.

[0140] The cathode active material is not limited to the materials listed above.

[0141] For example, a composite oxide having a spinel crystal structure or the like can be used as the cathode active material. Also, for example, a polyanion-based material can be used as the cathode active material. Examples of the polyanion-based material include materials having an olivine crystal structure, NASICON-type materials, and the like. Also, for example, a material containing sulfur can be used as the cathode active material.

[0142] Examples of the material having a spinel crystal structure include LiM 2 O 4The composite oxide represented by can be used. It is preferable that element M has Mn. For example, LiMn 2 O 4 can be used. Also, when element M has Ni in addition to Mn, the discharge voltage of the secondary battery may be improved and the energy density may be improved, which is preferable. Further, a small amount of lithium nickelate (LiNiO 2 O 4 etc.) is mixed with a lithium-containing material having a spinel-type crystal structure containing manganese such as LiMn 2 LiNi 1-x M x O 2 (M = Co, Al, etc.), whereby the characteristics of the secondary battery can be improved, which is preferable.

[0143] As a polyanion-based material, for example, a composite oxide having oxygen, metal A, metal M, and element Z can be used. Metal A is one or more of Li, Na, and Mg, metal M is one or more of Fe, Mn, Co, Ni, Ti, V, and Nb, and element Z is one or more of S, P, Mo, W, As, and Si.

[0144] As a material having an olivine-type crystal structure, for example, a composite material (general formula LiMPO 4 (M is one or more of Fe(II), Mn(II), Co(II), and Ni(II))) can be used. Representative examples of the general formula LiMPO 4 include LiFePO 4 LiNiPO 4 LiCoPO 4 LiMnPO 4 LiFe a Ni b PO 4 LiFe a Co b PO 4 LiFe a Mn b PO 4 LiNi a Co b PO 4 LiNi a Mn b PO 4(a + b is less than or equal to 1, 0 < a < 1, 0 < b < 1), LiFe c Ni d Co e PO 4 、LiFe c Ni d Mn e PO 4 、LiNi c Co d Mn e PO 4 (c + d + e is less than or equal to 1, 0 < c < 1, 0 < d < 1, 0 < e < 1), LiFe f Ni g Co h Mn i PO 4 (f + g + h + i is less than or equal to 1, 0 < f < 1, 0 < g < 1, 0 < h < 1, 0 < i < 1), lithium compounds such as the following can be used.

[0145] Also, composite materials such as the general formula Li (2-j) MSiO 4 (M is one or more of Fe(II), Mn(II), Co(II), Ni(II), 0 ≤ j ≤ 2) can be used. For the general formula Li (2-j) MSiO 4 Typical examples include Li (2-j) FeSiO 4 、Li (2-j) NiSiO 4 、Li (2-j) CoSiO 4 、Li (2-j) MnSiO 4 、Li (2-j) Fe k Ni l SiO 4 、Li (2-j) Fe k Co l SiO 4 、Li (2-j) Fe k Mn l SiO 4 、Li (2-j) Ni k Co l SiO 4 、Li (2-j) Ni k Mn l SiO 4(k + l is 1 or less, 0 < k < 1, 0 < l < 1), Li (2-j) Fe m Ni n Co q SiO 4 、Li (2-j) Fe m Ni n Mn q SiO 4 、Li (2-j) Ni m Co n Mn q SiO 4 (m + n + q is 1 or less, 0 < m < 1, 0 < n < 1, 0 < q < 1), Li (2-j) Fe r Ni s Co t Mn u SiO 4 (r + s + t + u is 1 or less, 0 < r < 1, 0 < s < 1, 0 < t < 1, 0 < u < 1), etc., lithium compounds can be used as materials.

[0146] Also, A x M 2 (XO 4 ) 3 (A = Li, Na, Mg, M = Fe, Mn, Ti, V, Nb, X = S, P, Mo, W, As, Si) represented by the general formula, NASICON-type compounds can be used. As NASICON-type compounds, there are Fe 2 (MnO 4 ) 3 、Fe 2 (SO 4 ) 3 、Li 3 Fe 2 (PO 4 ) 3 etc. Also, as the positive electrode active material, Li 2 MPO 4 F、Li 2 MP 2 O 7 、Li 5 MO 4 (M = Fe, Mn) represented by the general formula, compounds can be used.

[0147] Also, as the positive electrode active material, NaFeF 3, FeF 3 and other perovskite fluorides such as TiS 2 , MoS 2 and other metal chalcogenides (sulfides, selenides, tellurides), oxides having an inverse spinel crystal structure such as LiMVO 4 , vanadium oxide-based (V 2 O 5 , V 6 O 13 , LiV 3 O 8 etc.), manganese oxides, organic sulfur compounds, or other materials may be used.

[0148] Also, as the positive electrode active material, a borate-based material represented by the general formula LiMBO 3 (where M is Fe(II), Mn(II), Co(II)) may be used.

[0149] As materials containing sodium, for example, NaFeO 2 , Na 2 / 3 [Fe 1 / 2 Mn 1 / 2 O 2 , Na 2 / 3 [Ni 1 / 3 Mn 2 / 3 O 2 , Na 2 Fe 2 (SO 4 ) 3 , Na 3 V 2 (PO 4 ) 3 , Na 2 FePO 4 F, NaVPO 4 F, NaMPO 4 (where M is Fe(II), Mn(II), Co(II), Ni(II)), Na 2 FePO 4 F, or Na 4 Co 3 (PO 4 ) 2 P 2 O 7 , etc. Sodium-containing oxides may be used as the positive electrode active material.

[0150] Further, a lithium-containing metal sulfide may be used as the positive electrode active material. For example, Li 2 TiS 3 、Li 3 NbS 4 and the like can be mentioned.

[0151] As the positive electrode active material of one aspect of the present invention, two or more of the materials listed above may be mixed and used.

[0152] In a general secondary battery, as the charging voltage increases, the structure of the positive electrode active material becomes unstable, and the element M contained in the positive electrode active material may dissolve into the electrolytic solution. When the element M dissolves into the electrolytic solution, for example, the capacity of the positive electrode may decrease. The decrease in the capacity of the positive electrode leads to a decrease in the capacity of the secondary battery. Further, the element M dissolved in the electrolytic solution may precipitate on the surface of the negative electrode of the secondary battery. The inhibition of the reaction of the negative electrode of the precipitated element M leads to a decrease in the capacity of the secondary battery.

[0153] In the secondary battery using the positive electrode active material of one aspect of the present invention, since the structure of the positive electrode active material is stable even at a high charging voltage, elution of the element M contained in the positive electrode active material into the electrolytic solution can be suppressed.

[0154] In this specification and the like, the positive electrode active material of one aspect of the present invention may be expressed as a positive electrode material, or a positive electrode material for a secondary battery, etc. Further, in this specification and the like, the positive electrode active material of one aspect of the present invention preferably has a compound. Further, in this specification and the like, the positive electrode active material of one aspect of the present invention preferably has a composition. Further, in this specification and the like, the positive electrode active material of one aspect of the present invention preferably has a composite.

[0155] The battery cell according to one aspect of the present invention preferably has an electrolyte. As the electrolyte, a solid electrolyte having an inorganic material such as a sulfide-based or oxide-based material, or a solid electrolyte having a polymer material such as a PEO (polyethylene oxide)-based material can be used. When using a solid electrolyte, the installation of one or both of the separator and the spacer becomes unnecessary. In addition, since the entire battery can be solidified, the risk of liquid leakage is eliminated and the safety is dramatically improved.

[0156] As the solid electrolyte included in the solid electrolyte layer, for example, a sulfide-based solid electrolyte, an oxide-based solid electrolyte, a halide-based solid electrolyte, etc. can be used.

[0157] The sulfide-based solid electrolytes include thiolsilicon-based (Li 10 GeP 2 S 12 、Li 3.25 Ge 0.25 P 0.75 S 4 etc.), sulfide glasses (70Li 2 S·30P 2 S 5 、30Li 2 S·26B 2 S 3 ·44LiI、63Li 2 S·38SiS 2 ·1Li 3 PO 4 、57Li 2 S·38SiS 2 ·5Li 4 SiO 4 、50Li 2 S·50GeS 2 etc.), and sulfide crystallized glasses (Li 7 P 3 S 11 、Li 3.25 P 0.95 S 4 etc.). Sulfide-based solid electrolytes have advantages such as having materials with high conductivity, being synthesizable at low temperatures, and being relatively soft so that the conductive path is easily maintained even after charge and discharge.

[0158] Oxide-based solid electrolytes include materials having a perovskite crystal structure (La 2 / 3-x Li 3x TiO 3 etc.), materials having a NASICON crystal structure (Li 1-X Al X Ti 2-X (PO 4 ) 3 etc.), materials having a garnet crystal structure (Li 7 La 3 Zr 2 O 12 etc.), materials having a LISICON crystal structure (Li 14 ZnGe 4 O 16 etc.), LLZO (Li 7 La 3 Zr 2 O 12 ), oxide glasses (Li 3 PO 4 -Li 4 SiO 4 , 50Li 4 SiO 4 ·50Li 3 BO 3 etc.), and oxide crystallized glasses (Li 1.07 Al 0.69 Ti 1.46 (PO 4 ) 3 , Li 1.5 Al 0.5 Ge 1.5 (PO 4 ) 3 etc.). Oxide-based solid electrolytes have advantages such as being stable in the atmosphere.

[0159] Halide-based solid electrolytes include LiAlCl 4 , Li 3 InBr 6 , LiF, LiCl, LiBr, LiI, etc. Also, composite materials in which these halide-based solid electrolytes are filled in the pores of porous aluminum oxide or porous silica can be used as solid electrolytes.

[0160] Also, different solid electrolytes may be mixed and used.

[0161] Among them, Li having a NASICON-type crystal structure 1+x Al x Ti 2-x (PO 4 ) 3 (0 (x (1) (hereinafter referred to as LATP) contains elements such as aluminum and titanium that the positive electrode active material used in the secondary battery 400 of one aspect of the present invention may have. Therefore, a synergistic effect can be expected for improving the cycle characteristics, which is preferable. In addition, an improvement in productivity due to a reduction in the number of steps can also be expected. In this specification and the like, the NASICON-type crystal structure means M 2 (AO 4 ) 3 (M: transition metal, A: S, P, As, Mo, W, etc.) is a compound represented by, and MO 6 octahedron and AO 4 tetrahedron have a structure in which their vertices are shared and are three-dimensionally arranged.

[0162] In addition, the battery cell of one aspect of the present invention may have an electrolyte. The electrolyte has, for example, a solvent and an electrolyte. As the solvent of the electrolyte, an aprotic organic solvent is preferable. For example, ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate, chloroethylene carbonate, vinylene carbonate, γ-butyrolactone, γ-valerolactone, dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), methyl formate, methyl acetate, ethyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, 1,3-dioxane, 1,4-dioxane, dimethoxyethane (DME), dimethyl sulfoxide, diethyl ether, methyl diglyme, acetonitrile, benzonitrile, tetrahydrofuran, sulfolane, sultone, etc., or any combination and ratio of two or more of these can be used.

[0163] In addition, by using one or more ionic liquids (room-temperature molten salts), which are flame-retardant and have low volatility, as the solvent of the electrolyte, even if the internal region temperature of the secondary battery rises due to internal region short-circuit or overcharging, etc., rupture and ignition of the secondary battery can be prevented. An ionic liquid consists of a cation and an anion, and includes an organic cation and an anion. Examples of the organic cation used in the electrolyte include aliphatic onium cations such as quaternary ammonium cations, tertiary sulfonium cations, and quaternary phosphonium cations, and aromatic cations such as imidazolium cations and pyridinium cations. Examples of the anion used in the electrolyte include monovalent amide-based anions, monovalent methide-based anions, fluorosulfonic acid anions, perfluoroalkylsulfonic acid anions, tetrafluoroborate anions, perfluoroalkylborate anions, hexafluorophosphate anions, or perfluoroalkylphosphate anions, etc.

[0164] In addition, as the electrolyte dissolved in the above solvent, for example, LiPF 6 、LiClO 4 、LiAsF 6 、LiBF 4 、LiAlCl 4 、LiSCN、LiBr、LiI、Li 2 SO 4 、Li 2 B 10 Cl 10 、Li 2 B 12 Cl 12 、LiCF 3 SO 3 、LiC 4 F 9 SO 3 、LiC(CF 3 SO 2 ) 3 、LiC(C 2 F 5 SO 2 ) 3 、LiN(CF 3 SO 2 ) 2 、LiN(C 4 F 9 SO 2)(CF 3 SO 2 )、LiN(C 2 F 5 SO 2 ) 2 One or more of lithium salts such as these can be used in any combination and ratio.

[0165] For the electrolytic solution used in the secondary battery, it is preferable to use a highly purified electrolytic solution with a low content of particulate dust and elements other than the constituent elements of the electrolytic solution (hereinafter also simply referred to as "impurities"). Specifically, it is preferable that the weight ratio of impurities to the electrolytic solution is 1% or less, preferably 0.1% or less, and more preferably 0.01% or less.

[0166] In addition, additives such as vinylene carbonate, propane sultone (PS), tert-butylbenzene (TBB), fluoroethylene carbonate (FEC), lithium bis(oxalate) borate (LiBOB), and dinitrile compounds such as succinonitrile and adiponitrile may be added to the electrolytic solution. The concentration of the additive material may be, for example, 0.1 wt% or more and 5 wt% or less based on the whole solvent.

[0167] Also, a polymer gel electrolyte in which a polymer is swollen with an electrolytic solution may be used.

[0168] By using a polymer gel electrolyte, the safety against leakage and the like is enhanced. Also, the secondary battery can be made thinner and lighter.

[0169] As the polymer to be gelled, silicone gel, acrylic gel, acrylonitrile gel, polyethylene oxide-based gel, polypropylene oxide-based gel, fluorine-based polymer gel, etc. can be used.

[0170] As the polymer, for example, polymers having a polyalkylene oxide structure such as polyethylene oxide (PEO), PVDF, polyacrylonitrile, etc., and copolymers containing them can be used. For example, PVDF-HFP, which is a copolymer of PVDF and hexafluoropropylene (HFP), can be used. Further, the formed polymer may have a porous shape.

[0171] <Transistor> In the configuration of one aspect of the present invention, by using a memory element having an OS transistor, the reference voltage can be held in the memory element by taking advantage of the fact that the leakage current (hereinafter, off-current) flowing between the source and the drain at the off state is extremely low. At this time, since the power supply of the memory element can be turned off, the reference voltage can be held with extremely low power consumption by using the memory element having an OS transistor.

[0172] In addition, the memory element having an OS transistor can hold an analog potential. For example, the voltage of a secondary battery can be held in the memory element without converting it into a digital value using an analog-digital conversion circuit. The conversion circuit becomes unnecessary, and the circuit area can be reduced.

[0173] In addition, in the memory element using an OS transistor, since the reference voltage can be rewritten and read by charging or discharging charges, the acquisition and reading of the monitor voltage can be performed substantially an unlimited number of times. The memory element using an OS transistor does not involve a structural change at the atomic level unlike a magnetic memory or a resistive change memory, and thus has excellent rewrite resistance. Further, even when the memory element using an OS transistor performs repeated rewrite operations, the characteristic instability due to an increase in electron trapping centers as occurs in a flash memory is not recognized.

[0174] In addition, the OS transistor has characteristics such as an extremely low off-current and good switching characteristics even in a high-temperature environment. Therefore, even in a high-temperature environment, the charging or discharging of the assembled battery 120 can be controlled without malfunction.

[0175] In addition, a memory element using an OS transistor can be freely arranged by laminating it on a circuit using an Si transistor, etc., so that integration can be easily performed. Also, since the OS transistor can be manufactured using the same manufacturing equipment as the Si transistor, it can be manufactured at low cost.

[0176] In addition, the OS transistor can be a four-terminal semiconductor element including a back gate electrode in addition to the gate electrode, source electrode, and drain electrode. Depending on the voltage applied to the gate electrode or the back gate electrode, an electric circuit network can be configured in which the input and output of the signal flowing between the source and the drain can be independently controlled. Therefore, circuit design can be performed with the same concept as that of an LSI. In addition, the OS transistor has better electrical characteristics than the Si transistor in a high-temperature environment. Specifically, since the ratio of the on-current to the off-current is large even at a high temperature of 100°C or higher and 200°C or lower, preferably 125°C or higher and 150°C or lower, a good switching operation can be performed.

[0177] It is preferable to use an OS transistor as the transistor 162. Also, an OS transistor may be used as the transistor 132.

[0178] In addition, a comparator may be configured using an OS transistor.

[0179] This embodiment can be appropriately combined with the descriptions of other embodiments.

[0180] (Embodiment 2) In this embodiment, a configuration example of a semiconductor device according to one aspect of the present invention will be described. The semiconductor device according to one aspect of the present invention samples (acquires) the potential between the positive and negative electrodes of a secondary battery at predetermined time intervals during charge and discharge, and compares the sampled potential with the potential between the positive and negative electrodes after sampling, thereby having a function of detecting an instantaneous potential fluctuation (here, the potential drops) due to a micro short circuit. By repeating the sampling at predetermined time intervals, it is possible to respond to the potential fluctuation of the secondary battery during charge and discharge, and the semiconductor device can operate using the potential between the positive and negative electrodes of the secondary battery.

[0181] In this embodiment, the potential fluctuations of the secondary battery and the semiconductor device during charging are described using a timing chart or the like. Since those skilled in the art can easily understand the potential fluctuations during discharging, the description thereof is omitted.

[0182] <An example of the detection circuit> FIG. 6A is a circuit diagram showing a configuration example of the detection circuit MSD. The detection circuit MSD includes transistors 11 to 15, a capacitive element C11, and a comparator 50. In the drawings described in this specification and the like, the main signal flow is indicated by arrows or lines, and power supply lines and the like may be omitted. As the comparator 50 included in the detection circuit MSD, a hysteresis comparator may be used. Note that the detection circuit MSD may perform detection in a plurality of serially connected battery cells, or may perform detection for each battery cell.

[0183] Further, the detection circuit MSD shown in FIG. 6A has a terminal VC1, a wiring VB1_IN to which a predetermined potential VB1 is supplied, a wiring VB2_IN to which a predetermined potential VB2 is supplied, a wiring SH_IN to which a sampling signal is supplied, and an output terminal S_OUT.

[0184] Here, the predetermined potential VB1 is higher than the predetermined potential VB2, and the predetermined potential VB2 is higher than the potential of the terminal VSSS.

[0185] FIG. 6B is different from FIG. 6A in that the transistors 11 to 15 included in the detection circuit MSD have a second gate.

[0186] FIG. 6C is different from FIG. 6B in that it has a terminal VSSS, a storage element 114 connected to the wiring VB1_IN, and a storage element 114 connected to the wiring VB2_IN. Also, in FIG. 6C, one of the source and drain of transistor 11, one of the source and drain of transistor 13, and one electrode of the capacitor element C11 are electrically connected to the terminal VSSS. Since the potential VB1 and the potential VB2 are applied to the wiring VB1_IN and the wiring VB_2 via the storage element 114, respectively, the potential applied by the storage element 114 can be held. Therefore, the power supply of the voltage generation circuit that supplies the potential VB1 and the potential VB2, more specifically, for example, the voltage generation circuit 119, can be turned off or set to a standby state.

[0187] The transistors 11 to 15 are n-channel type transistors. In this specification and the like, an example in which the detection circuit MSD is configured using n-channel type transistors is shown, but p-channel type transistors may also be used. It is easily understood by those skilled in the art to change the transistors to p-channel type from the circuit diagram configured using n-channel type transistors, and thus the description thereof is omitted.

[0188] In the detection circuit MSD, one of the source or drain of transistor 11 is electrically connected to the terminal VSSS, the other of the source or drain of transistor 11 is electrically connected to one of the source or drain of transistor 12 and one of the source or drain of transistor 15, the gate of transistor 11 is electrically connected to the wiring VB1_IN, and the other of the source or drain of transistor 12 and the gate of transistor 12 are electrically connected to the terminal VC1.

[0189] One of the source or drain of transistor 13 is electrically connected to terminal VSSS, and the other of the source or drain of transistor 13 is electrically connected to one of the source or drain of transistor 14 and the inverting input terminal of comparator 50. The gate of transistor 13 is electrically connected to wiring VB2_IN. The other of the source or drain of transistor 14 and the gate of transistor 14 are electrically connected to terminal VC1.

[0190] Also, the other of the source or drain of transistor 15 is electrically connected to the other terminal of capacitor element C11 and the non-inverting input terminal of comparator 50. The gate of transistor 15 is electrically connected to wiring SH_IN. One terminal of capacitor element C11 is electrically connected to terminal VSSS. The output terminal of comparator 50 is electrically connected to output terminal S_OUT. Note that one terminal of capacitor element C11 may be electrically connected to a wiring other than terminal VSSS as long as it is a wiring to which a predetermined potential is supplied.

[0191] Here, a connection portion where the other of the source or drain of transistor 11, one of the source or drain of transistor 12, and one of the source or drain of transistor 15 are electrically connected is referred to as node N11. A connection portion where the other of the source or drain of transistor 13, one of the source or drain of transistor 14, and the inverting input terminal of comparator 50 are electrically connected is referred to as node N12. A connection portion where the other of the source or drain of transistor 15, the other terminal of capacitor element C11, and the non-inverting input terminal of comparator 50 are electrically connected is referred to as node N13.

[0192] Further, transistor 11 and transistor 12 constitute a first source follower, and transistor 13 and transistor 14 constitute a second source follower. That is, the gate of transistor 11 corresponds to the input of the first source follower, and the first source follower outputs a signal to node N11. The gate of transistor 13 corresponds to the input of the second source follower, and the second source follower outputs a signal to node N12.

[0193] An example of the operation of the detection circuit MSD will be described using the circuit shown in FIG. 6C.

[0194] When charging starts in the battery pack, the sampling signal applied to wiring SH_IN becomes high level at predetermined intervals. A potential higher than that of potential VB2 is given as potential VB1. As charging progresses, the potential of node N11 and the potential of node N12 increase.

[0195] When the positive electrode potential instantaneously drops due to the occurrence of a micro short, the potentials of node N11 and node N12 instantaneously drop. On the other hand, when the sampling signal applied to wiring SH_IN is at a low level, the potential of node N13 is not affected by the potential of node N11, and the potential of node N12 becomes lower than the potential of node N13. Then, the output of comparator 50 is inverted, and a micro short is detected.

[0196] Further, in order to improve the detection accuracy of a micro short, the voltage of the secondary battery may be converted into digital data by an analog-to-digital conversion circuit, and an operation may be performed based on the digital data using a processor unit or the like, and the waveform of charging or the waveform of discharging may be analyzed to detect or predict a micro short. For example, in the waveform of charging or the waveform of discharging, detection or prediction of a micro short is performed using the displacement of the voltage error at each time step. The displacement of the voltage error is obtained by calculating the voltage error and calculating the difference from the previous step.

[0197] In order to improve the detection accuracy of a micro short, a neural network may be used.

[0198] A neural network is a technique and is neural network processing performed in a neural network unit (including, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an APU (Accelerated Processing Unit), memory, etc.). Note that the APU refers to a chip that integrates a CPU and a GPU into one.

[0199] The secondary battery mounted on the device is random because it is likely to depend on the user's usage method regarding discharge, but the charging curve is easier to predict than discharge because the charging conditions are determined. By using a certain number of charging curves as learning data, an accurate value can be predicted using a neural network. If the charging curve is obtained, the SOC (State of charge), etc. can be obtained using a neural network. For the operation of the neural network, for example, a microprocessor or the like may be used.

[0200] Specifically, various obtained data are evaluated and learned using machine learning or artificial intelligence, the degree of deterioration of the predicted secondary battery is analyzed, and if there is an abnormality, charging of the secondary battery is stopped or the current density of constant current charging is adjusted.

[0201] For example, in an electric vehicle, learning data can be obtained during driving and the deterioration state of the secondary battery can be grasped. Note that a neural network is used for predicting the deterioration state of the secondary battery. The neural network can be configured by a neural network having a plurality of hidden layers, that is, a deep neural network. Note that the learning in the deep neural network is sometimes called deep learning.

[0202] Machine learning first extracts feature values from learning data. The relative change amount that changes over time is extracted as a feature value, and a neural network is trained based on the extracted feature values. The learning means can train the neural network based on different learning patterns for each time interval. The connection weights applied to the neural network can be updated according to the learning results based on the learning data.

[0203] As a method for estimating the state of charge of a secondary battery using a neural network, it can also be obtained by performing calculation processing using a regression model, such as a Kalman filter.

[0204] The Kalman filter is a type of infinite impulse response filter. Also, multiple regression analysis is one of the multivariate analyses, which is obtained by making multiple independent variables in regression analysis. Examples of multiple regression analysis include the least squares method. In regression analysis, a large number of time series of observed values are required, while the Kalman filter has the merit that an optimal correction coefficient can be obtained sequentially as long as a certain amount of data is accumulated. Also, the Kalman filter can be applied to non-stationary time series.

[0205] As a method for estimating the internal resistance and state of charge (SOC) of a secondary battery, a non-linear Kalman filter (specifically, an unscented Kalman filter (also called UKF)) can be used. Also, an extended Kalman filter (also called EKF) can be used. SOC indicates the state of charge (also called the charge rate), and is an index with 100% when fully charged and 0% when fully discharged.

[0206] The initial parameters obtained by the optimization algorithm are collected every n (n is an integer, for example, 50) cycles, and high-precision SOC estimation can be performed by subjecting these data groups to neural network processing using them as teacher data.

[0207] The learning system includes a teacher data creation device and a learning device. The teacher data creation device creates teacher data used when the learning device conducts learning. The teacher data includes data where the processing target data and the recognition target are the same, and the evaluation of the label corresponding to that data. The teacher data creation device includes an input data acquisition unit, an evaluation acquisition unit, and a teacher data creation unit. The input data acquisition unit may acquire data stored in a storage device, or may acquire input data for learning via the Internet. The input data is data used for learning and includes the current value and voltage value of a secondary battery. Also, the teacher data does not necessarily have to be measured data. By conditioning the initial parameters, diversity can be provided, data close to the actual measurement can be created, and the state of charge (SOC) can be estimated by performing neural network processing using those predetermined characteristic databases as teacher data. Based on the charge and discharge characteristics of a single battery, data close to the actual measurement can be created, and by performing neural network processing using those predetermined characteristic databases as teacher data, the SOC of the same type of battery can be efficiently estimated.

[0208] When the deterioration of the secondary battery progresses, if the FCC of the initial parameters changes significantly, there may be an error in the SOC. Therefore, the initial parameters used in the calculation for estimating the SOC may be updated. The initial parameters to be updated are calculated by an optimization algorithm using data on the charge and discharge characteristics measured in advance. By performing calculation processing using a regression model with the updated initial parameters, for example, a Kalman filter, it is possible to perform highly accurate SOC estimation even after deterioration. In this specification, performing calculation processing using a Kalman filter is also expressed as Kalman filter processing.

[0209] The timing for updating the initial parameters may be arbitrary, but in order to perform highly accurate SOC estimation, it is preferable that the update frequency is higher, and it is more preferable to update regularly and continuously. Note that when the temperature of the secondary battery is high, if the SOC is high, the deterioration may progress easily. In such a case, it is preferable to discharge the secondary battery to lower the SOC in order to suppress the deterioration of the secondary battery.

[0210] This embodiment can be appropriately combined with the descriptions of other embodiments.

[0211] (Embodiment 3) This embodiment shows a configuration example of a comparator.

[0212] FIG. 7 shows an example of the configuration of the comparator 50 described in the previous embodiment. The comparator 50 includes transistors 21 to 25. The comparator 50 also has a wiring VBM_IN to which the negative electrode potential of the secondary battery is supplied, a wiring VBP_IN to which the positive electrode potential VBP of the secondary battery is supplied, a wiring VB3_IN to which a predetermined potential VB3 is supplied, an input terminal CP1_IN, an input terminal CM1_IN, an output terminal CP1_OUT, and an output terminal CM1_OUT.

[0213] When the comparator 50 in FIG. 7 is applied to the cell balance circuit 130 and the detection circuit 185 in FIG. 4, for example, a potential is applied to the wiring VBP_IN from the terminal VC1 and to the wiring VBM_IN from the terminal VC2.

[0214] Here, the predetermined potential VB3 is a potential higher than the negative electrode potential VBM. In the comparator 50, the positive electrode potential VBP is the high power supply potential, and the negative electrode potential VBM is the low power supply potential.

[0215] In the comparator 50, one of the source or drain of the transistor 21 is electrically connected to the wiring VBM_IN, the other of the source or drain of the transistor 21 is electrically connected to one of the source or drain of the transistor 22 and one of the source or drain of the transistor 24, and the gate of the transistor 21 is electrically connected to the wiring VB3_IN.

[0216] The other of the source or drain of transistor 22 is electrically connected to one of the source or drain of transistor 23 and output terminal CM1_OUT, and the other of the source or drain of transistor 23 and the gate of transistor 23 are electrically connected to wiring VBP_IN, and the gate of transistor 22 is electrically connected to input terminal CP1_IN.

[0217] The other of the source or drain of transistor 24 is electrically connected to one of the source or drain of transistor 25 and output terminal CP1_OUT, and the other of the source or drain of transistor 25 and the gate of transistor 25 are electrically connected to wiring VBP_IN, and the gate of transistor 24 is electrically connected to input terminal CM1_IN.

[0218] Also, a plurality of circuits shown in FIG. 7 may be connected in parallel and used as comparator 50. That is, the output of the comparator shown in FIG. 7 may be input to the next-stage comparator 50, and a plurality of comparators may be connected and used.

[0219] This embodiment can be appropriately combined with the descriptions of other embodiments.

[0220] (Embodiment 4) A configuration example of a semiconductor device applicable to the battery control circuit described in the above embodiment will be described.

[0221] The semiconductor device shown in FIG. 8 includes transistor 300, transistor 500, and capacitor element 600. In the example shown in FIG. 8, the semiconductor device includes a plurality of transistors 300 (hereinafter, the two transistors 300 shown in the semiconductor device shown in FIG. 8 may be referred to as transistor 300(1) and transistor 300(2), respectively).

[0222] FIG. 13A is a cross-sectional view of transistor 500 in the channel length direction, and FIG. 13B is a cross-sectional view of transistor 500 in the channel width direction.

[0223] The transistor 500 is an OS transistor. Since the transistor 500 has a small off-current, by using it for the transistors included in the semiconductor device, it is possible to retain data written over a long period of time in the semiconductor device.

[0224] The transistor 500 is, for example, an n-channel transistor.

[0225] Here, the circuit 101a included in the battery control circuit 101 described in the previous embodiment is preferably configured using the transistor shown as the transistor 500. Also, for example, the circuit 101b included in the battery control circuit 101 described in the previous embodiment is preferably configured using at least two or more transistors shown as the transistor 300.

[0226] The semiconductor device described in the present embodiment has a transistor 300, a transistor 500, and a capacitor element 600 as shown in FIG. 8. The transistor 500 is provided above the transistor 300, and the capacitor element 600 is provided above the transistor 300 and the transistor 500. The layer 385 is the layer in which the transistor 300 is provided. In FIG. 8, for example, the layer 385 has a substrate 311 and the layers sandwiched between the substrate 311 and the insulator 322. The layer 585 is the layer in which the transistor 500 is provided. In FIG. 8, for example, the layer 585 has the layers sandwiched between the insulator 514 and the insulator 574. The substrate 311, the insulator 322, the insulator 514, and the insulator 574 will be described later.

[0227] The transistor 300 is provided on the substrate 311 and has a conductor 316, an insulator 315, a semiconductor region 313 formed of a part of the substrate 311, a low-resistance region 314a that functions as a source region or a drain region, and a low-resistance region 314b. The conductor 316 can function as the gate of the transistor 300. The insulator 315 can function as the gate insulating film of the transistor 300.

[0228] Note that the transistor 300 can be used, for example, for the transistors 140 and 150 shown in the above embodiment.

[0229] The transistors 140 and 150 shown in the above embodiment may be called power MOSFETs (Power MOSFETs). The transistor 300 illustrated in FIGS. 8, 9, 10A, 10B, and 10C is particularly preferably applied to the transistors 140 and 150. The transistor 300 shown in FIGS. 8, 9, 10A, 10B, and 10C is called a D-MOS (Double Diffusion Metal Oxide Semiconductor) FET.

[0230] The transistor 300 shown in FIG. 8 is a planar transistor. By using one of the low-resistance regions 314a and 314b and the other as the source region and the drain region respectively, it can operate as a MOSFET. Here, however, both the low-resistance region 314a and the low-resistance region 314b function as sources, and a region 319 is formed outside the low-resistance region 314a and the low-resistance region 314b. A low-resistance region 317 that functions as a drain is provided in a region below the semiconductor region 313 of the silicon substrate in the cross-section shown in FIG. 8, whereby the transistor 300 can function as a D-MOSFET. Also, a back surface electrode 318 is provided below the low-resistance region 317 so that it can function as a drain electrode. Note that both the low-resistance region 314a and the low-resistance region 314b may function as drains, and the low-resistance region 317 may function as a source. The region 319 is preferably a region having a polarity opposite to that of the low-resistance region 314a and the low-resistance region 314b. For example, when the low-resistance region 314a and the low-resistance region 314b are n-type regions, the region 319 is preferably a p-type region. Alternatively, the region 319 may be a high-resistance region. The region 319 may be an intrinsic region. A conductor 328b (or the conductor 328c shown in FIG. 10A etc.) is preferably provided on the upper surfaces of the low-resistance region 314a and the low-resistance region 314b. Also, the conductor 328b may be provided on the upper surface of the region 319.

[0231] Note that there may be cases where the low-resistance region 314a, the low-resistance region 314b, and the low-resistance region 317 are not provided. Even if these low-resistance regions are not provided, by connecting to the semiconductor region 313 of the substrate 311 etc. and providing the conductor 328, the back surface electrode 318, etc., these electrodes may function as a source electrode, a drain electrode, etc.

[0232] Here, before providing the back electrode, it is preferable to polish the substrate 311. For example, by polishing the substrate 311, a natural oxide film or the like on the surface of the substrate 311 can be removed, and an increase in resistance can be suppressed. Further, it is preferable to polish the substrate 311 to reduce its thickness. For example, the thickness of the substrate 311 is preferably 5 μm or more and 300 μm or less, more preferably 10 μm or more and 150 μm or less. By reducing the thickness of the substrate 311, in the transistor 300, the distance between the source and the drain can be made closer, and the on-current of the transistor can be increased.

[0233] Here, when the substrate 311 is polished to be thinned, it is preferable to provide a support substrate on the opposite side, specifically, for example, on the conductor 632 and the insulator 640. As the support substrate, for example, a resin substrate or the like can be used. Also, a substrate having an adhesive layer may be used as the support substrate. As the adhesive layer, a removable adhesive may be used. In such a case, when polishing the substrate 311, the first support substrate is adhered by the adhesive layer, and after polishing, the back electrode 318 is formed. A second support substrate is provided on the side opposite to the first support substrate so as to cover the back electrode 318. After removing the first support substrate, the conductor 632 is exposed. Then, the conductor 632 is connected using a bump, wire bonding, clip bonding using a conductive clip, or the like.

[0234] In FIG. 8, the low resistance regions 314a and 314b are in contact with the region 319 which is a region of the opposite polarity, thereby forming a pn junction. Such a pn junction region is called a parasitic diode in this specification and the like. The parasitic diode has functions such as reverse current prevention and rectification. Also, the parasitic diode has a function of protecting the transistor. When the parasitic diode is formed between the source and the drain, for example, between the low resistance regions 314a and 314b and the low resistance region 317, electric field concentration or the like when a high voltage is applied between the source and the drain is alleviated, and breakdown or deterioration of the transistor can be suppressed.

[0235] FIG. 8 shows an example in which plugs such as conductor 328 are electrically connected to low-resistance regions 314a and 314b, respectively. However, in the example shown in FIG. 10A, an example in which conductor 328c is electrically connected to a plurality of low-resistance regions is shown. The conductor 328c preferably has a shape that covers at least a part of each of the plurality of low-resistance regions. Further, the conductor 328c preferably overlaps at least a part of each of the plurality of low-resistance regions.

[0236] As shown in FIGS. 11A and 11B, in transistor 300, three or more low-resistance regions may be provided.

[0237] As shown in FIG. 11A, the transistor 300 may be provided on a semiconductor region sandwiched between two low-resistance regions and may have a plurality of sets of a conductor 316 that functions as a gate electrode and an insulator 315 that is provided between the conductor 316 and the semiconductor region and functions as a gate insulating film. Further, the plurality of conductors 316 are preferably electrically connected to each other. Further, the plurality of low-resistance regions are preferably electrically connected to each other via a conductor 328b or the like.

[0238] FIG. 11B shows an example in which a plurality of low-resistance regions are provided in a trench-type transistor shown in FIG. 10B or the like (details will be described later). As shown in FIG. 11B, it may have a plurality of sets of a conductor 316 that functions as a gate electrode and is sandwiched between two low-resistance regions, and an insulator 315 that is sandwiched between the conductor 316 and the low-resistance region and functions as a gate insulating film. Further, the plurality of conductors 316 are preferably electrically connected to each other. Further, the plurality of low-resistance regions are preferably electrically connected to each other via a conductor 328, a conductor 328c, or the like. ss

[0239] Note that the transistor 300 may be either p-channel type or n-channel type.

[0240] In the regions where the channel of the semiconductor region 313 is formed, the regions in the vicinity thereof, the source region, or the drain region, such as the low-resistance regions 314a, 314b, and 317, it is preferable to include a semiconductor such as a silicon-based semiconductor, and it is preferable to include single-crystalline silicon. Alternatively, it may be formed of a material having Ge (germanium), SiGe (silicon germanium), GaAs (gallium arsenide), GaAlAs (gallium aluminum arsenide), InP (indium phosphide), SiC (silicon carbide), ZnSe (zinc selenide), GaN (gallium nitride), GaOx (gallium oxide; x is a real number greater than 0), etc. A configuration using silicon in which stress is applied to the crystal lattice and the effective mass is controlled by changing the lattice spacing may also be used. Alternatively, by using GaAs, GaAlAs, etc., the transistor 300 may be a HEMT (High Electron Mobility Transistor).

[0241] The low-resistance regions 314a, 314b, and 317 include, in addition to the semiconductor material applied to the semiconductor region 313, an element that imparts n-type conductivity such as arsenic or phosphorus, or an element that imparts p-type conductivity such as boron.

[0242] The conductor 316 that functions as a gate electrode can be made of a conductive material such as a semiconductor material such as silicon, a metal material, an alloy material, or a metal oxide material, which includes an element that imparts n-type conductivity such as arsenic or phosphorus, or an element that imparts p-type conductivity such as boron.

[0243] Note that since the work function is determined by the material of the conductor, the threshold voltage of the transistor can be adjusted by selecting the material of the conductor. Specifically, it is preferable to use one or more selected from materials such as titanium nitride and tantalum nitride for the conductor. Furthermore, in order to achieve both conductivity and embedding properties, it is preferable to use one or more selected from metal materials such as tungsten and aluminum as a laminate for the conductor, and it is particularly preferable to use tungsten from the viewpoint of heat resistance.

[0244] Note that the transistor 300 shown in FIG. 8 is an example and is not limited to its structure. An appropriate transistor may be used according to the circuit configuration and driving method. For example, when the semiconductor device is composed of only OS transistors, the configuration of the transistor 300 may be the same as that of the transistor 500 using an oxide semiconductor. Details of the transistor 500 will be described later.

[0245] An insulator 320, an insulator 322, an insulator 324, and an insulator 326 are sequentially stacked and provided covering the transistor 300.

[0246] As the insulator 320, the insulator 322, the insulator 324, and the insulator 326, for example, silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, aluminum oxide, aluminum oxynitride, aluminum nitride oxide, aluminum nitride, etc. may be used.

[0247] Note that in this specification, silicon oxynitride refers to a material having a higher oxygen content than nitrogen in its composition, and silicon nitride oxide refers to a material having a higher nitrogen content than oxygen in its composition. Also, in this specification, aluminum oxynitride refers to a material having a higher oxygen content than nitrogen in its composition, and aluminum nitride oxide refers to a material having a higher nitrogen content than oxygen in its composition.

[0248] The insulator 322 may have a function as a planarization film that planarizes the step formed by the transistor 300 or the like provided below it. For example, the upper surface of the insulator 322 may be planarized by a planarization process using a chemical mechanical polishing (CMP) method or the like to enhance flatness.

[0249] Also, for the insulator 324, it is preferable to use a film having a barrier property such that hydrogen and impurities do not diffuse from the substrate 311 or the transistor 300 or the like into the region where the transistor 500 is provided.

[0250] As an example of a film having a barrier property against hydrogen, for example, silicon nitride formed by CVD method can be used. Here, when hydrogen diffuses into a semiconductor element having an oxide semiconductor such as transistor 500, the characteristics of the semiconductor element may deteriorate. Therefore, it is preferable to use a film that suppresses the diffusion of hydrogen between transistor 500 and transistor 300. Specifically, the film that suppresses the diffusion of hydrogen is a film with a small amount of hydrogen desorption.

[0251] The amount of hydrogen desorption can be analyzed, for example, using temperature-programmed desorption gas analysis method (TDS). For example, the amount of hydrogen desorption of insulator 324 is such that in the TDS analysis, in the range where the surface temperature of the film is from 50°C to 500°C, the desorption amount converted to hydrogen atoms, when converted per unit area of insulator 324, is 10×10 15 atoms / cm 2 Hereinafter, preferably 5×10 15 atoms / cm 2 or less would be sufficient.

[0252] Note that insulator 326 preferably has a lower dielectric constant than insulator 324. For example, the relative dielectric constant of insulator 326 is preferably less than 4, more preferably less than 3. Also, for example, the relative dielectric constant of insulator 326 is preferably 0.7 times or less, more preferably 0.6 times or less, of the relative dielectric constant of insulator 324. By using a material with a low dielectric constant as the interlayer film, the parasitic capacitance generated between wirings can be reduced.

[0253] In addition, a capacitor element 600, or conductors 328 and 330 that are connected to the transistor 500 are embedded in the insulators 320, 322, 324, and 326. In the example shown in FIG. 8, the conductor 328 is provided so as to be embedded in the insulators 320 and 322, and the conductor 330 is provided so as to be embedded in the insulators 324 and 326. Note that the conductors 328 and 330 have functions as plugs or wirings. In addition, conductors having functions as plugs or wirings may be given the same reference numeral in a lump for a plurality of structures. In this specification and the like, a wiring and a plug connected to the wiring may be an integral body. That is, a part of the conductor may function as a wiring, and a part of the conductor may function as a plug.

[0254] Here, when semiconductor elements are connected to each other, or a semiconductor element is connected to a conductor, or conductors are connected to each other via a plug or a wiring, for example, they are electrically connected.

[0255] As materials for each plug and wiring (conductors 328, 330, etc.), conductive materials such as metal materials, alloy materials, metal nitride materials, or metal oxide materials can be used alone or in a stacked manner. It is preferable to use a high melting point material such as tungsten or molybdenum that achieves both heat resistance and conductivity, and it is more preferable to use tungsten. Alternatively, it is preferable to form with a low resistance conductive material such as aluminum or copper. By using a low resistance conductive material, the wiring resistance can be reduced.

[0256] An insulator 321 that functions as an element isolation layer is provided between the transistor 300(1) and the transistor 300(2). The element isolation layer can be formed using a method such as LOCOS (LOCal Oxidation of Silicon) method or STI (Shallow Trench Isolation) method. As the insulating layer 245, for example, an inorganic insulating film such as a silicon oxide film or silicon nitride, or an organic insulating film such as polyimide or acrylic can be used. Note that the insulating layer 245 may have a multilayer structure.

[0257] Note that if the distance between the transistor 300(1) and the transistor 300(2) is sufficiently large, the insulator 321 may not be provided.

[0258] One of the drain and source of the transistor 300(1) is electrically connected to one of the drain and source of the transistor 300(2) via the back electrode 318. The other of the drain and source of the transistor 300(1) is connected to the conductor 610b via a conductor 328 or the like. The conductor 610b can be connected to various semiconductor elements included in the semiconductor device according to one aspect of the present invention. Further, when the semiconductor device according to one aspect of the present invention is applied as a circuit electrically connected to a secondary battery, more specifically, for example, a protection circuit, a control circuit, etc., the conductor 610b can be electrically connected to the secondary battery or an electrode of a secondary battery group, more specifically, for example, a negative electrode or a positive electrode.

[0259] In the semiconductor device shown in FIG. 8, the transistor 300 has a conductor 328b. The conductor 328b is provided on the low resistance regions 314a, 314b, etc. Further, the insulator 315 may have a region sandwiched between the low resistance region 314a and the conductor 328b and a region sandwiched between the low resistance region 314b and the conductor 328b. The conductor 328 is provided on the conductor 328b. The conductor 328b may have a region sandwiched between the low resistance region 314a and the conductor 328 or a region sandwiched between the low resistance region 314b and the conductor 328. Further, as shown in FIG. 9, a part of the region 319 may be provided so as to be formed deeply.

[0260] A wiring layer may be provided on the insulator 326 and the conductor 330. For example, in FIG. 8, the insulator 350, the insulator 352, and the insulator 354 are sequentially stacked and provided. Further, a conductor 356 is formed on the insulator 350, the insulator 352, and the insulator 354. The conductor 356 has a function as a plug connected to the transistor 300 or a wiring. Note that the conductor 356 can be provided using the same material as the conductor 328 and the conductor 330.

[0261] Note that, for example, as with the insulator 324, it is preferable to use an insulator having a barrier property against hydrogen for the insulator 350. Further, the conductor 356 preferably includes a conductor having a barrier property against hydrogen. In particular, a conductor having a barrier property against hydrogen is formed in an opening of the insulator 350 having a barrier property against hydrogen. With this configuration, the transistor 300 and the transistor 500 can be separated by a barrier layer, and diffusion of hydrogen from the transistor 300 to the transistor 500 can be suppressed.

[0262] Note that, as the conductor having a barrier property against hydrogen, for example, tantalum nitride or the like may be used. Further, by laminating tantalum nitride and tungsten having high conductivity, diffusion of hydrogen from the transistor 300 can be suppressed while maintaining the conductivity as a wiring. In this case, it is preferable that the tantalum nitride layer having a barrier property against hydrogen is in contact with the insulator 350 having a barrier property against hydrogen.

[0263] In the above, the wiring layer including the conductor 356 has been described, but the semiconductor device according to the present embodiment is not limited to this. A plurality of wiring layers similar to the wiring layer including the conductor 356 may be formed.

[0264] On the insulator 354, an insulator 510, an insulator 512, an insulator 514, and an insulator 516 are sequentially stacked and provided. Any of the insulator 510, the insulator 512, the insulator 514, and the insulator 516 is preferably made of a material having a barrier property against one or more of oxygen and hydrogen.

[0265] For example, for the insulators 510 and 514, it is preferable to use a film having a barrier property that prevents hydrogen and impurities from diffusing into the region where the transistor 500 is provided from the region where the substrate 311 or the transistor 300 is provided. Therefore, the same material as that of the insulator 324 can be used.

[0266] As an example of a film having a barrier property against hydrogen, silicon nitride formed by CVD can be used. Here, when hydrogen diffuses into a semiconductor element having an oxide semiconductor such as the transistor 500, the characteristics of the semiconductor element may deteriorate. Therefore, it is preferable to use a film that suppresses the diffusion of hydrogen between the transistor 500 and the transistor 300. Specifically, the film that suppresses the diffusion of hydrogen is a film having a small amount of hydrogen desorption.

[0267] Also, as a film having a barrier property against hydrogen, for example, for the insulators 510 and 514, it is preferable to use metal oxides such as aluminum oxide, hafnium oxide, and tantalum oxide.

[0268] In particular, aluminum oxide has a high blocking effect of preventing the film from permeating both oxygen and impurities such as hydrogen and moisture that are factors causing fluctuations in the electrical characteristics of the transistor. Therefore, aluminum oxide can prevent the mixing of impurities such as hydrogen and moisture into the transistor 500 during and after the manufacturing process of the transistor. In addition, it is possible to suppress the release of oxygen from the oxide constituting the transistor 500. Therefore, it is suitable to be used as a protective film for the transistor 500.

[0269] Also, for example, for the insulators 512 and 516, the same material as that of the insulator 320 can be used. Further, by applying a material having a relatively low dielectric constant to these insulators, the parasitic capacitance generated between the wirings can be reduced. For example, as the insulators 512 and 516, a silicon oxide film or a silicon oxynitride film can be used.

[0270] In addition, conductors such as the conductor 518 and the conductor (for example, conductor 503) constituting the transistor 500 are embedded in the insulators 510, 512, 514, and 516. Note that the conductor 518 functions as a plug connected to the conductor 610b, the transistor 300, or the capacitor element 600, or as a wiring. The conductor 518 can be provided using the same material as the conductors 328 and 330.

[0271] In particular, the conductor 518 in the region in contact with the insulators 510 and 514 is preferably a conductor having a barrier property against oxygen, hydrogen, and water. With this configuration, the transistor 300 and the transistor 500 can be separated by a layer having a barrier property against oxygen, hydrogen, and water, and diffusion of hydrogen from the transistor 300 to the transistor 500 can be suppressed.

[0272] A transistor 500 is provided above the insulator 516.

[0273] As shown in FIGS. 13A and 13B, the transistor 500 includes a conductor 503 arranged to be embedded in the insulators 514 and 516, an insulator 520 arranged on the insulator 516 and the conductor 503, an insulator 522 arranged on the insulator 520, an insulator 524 arranged on the insulator 522, an oxide 530a arranged on the insulator 524, an oxide 530b arranged on the oxide 530a, conductors 542a and 542b arranged apart from each other on the oxide 530b, an insulator 580 arranged on the conductors 542a and 542b and having an opening formed by overlapping between the conductor 542a and the conductor 542b, an oxide 530c arranged on the bottom surface and the side surface of the opening, an insulator 550 arranged on the formation surface of the oxide 530c, and a conductor 560 arranged on the formation surface of the insulator 550.

[0274] Also, as shown in FIGS. 13A and 13B, it is preferable that an insulator 544 is disposed between the oxides 530a, 530b, the conductors 542a and 542b, and the insulator 580. Also, as shown in FIGS. 13A and 13B, the conductor 560 preferably includes a conductor 560a provided inside the insulator 550 and a conductor 560b provided so as to be embedded inside the conductor 560a. Also, as shown in FIGS. 13A and 13B, it is preferable that an insulator 574 is disposed on the insulator 580, the conductor 560, and the insulator 550.

[0275] Note that hereinafter, the oxides 530a, 530b, and 530c may be collectively referred to as an oxide 530.

[0276] Note that in the transistor 500, a configuration in which three layers of the oxides 530a, 530b, and 530c are laminated in a region where a channel is formed and in its vicinity is shown, but the present invention is not limited thereto. For example, a single layer of the oxide 530b, a two-layer structure of the oxides 530b and 530a, a two-layer structure of the oxides 530b and 530c, or a laminated structure of four or more layers may be provided. Also, in the transistor 500, the conductor 560 is shown as a two-layer laminated structure, but the present invention is not limited thereto. For example, the conductor 560 may have a single-layer structure or a laminated structure of three or more layers. Also, the transistor 500 shown in FIGS. 8 and 13A is an example, and the present invention is not limited to its structure, and an appropriate transistor may be used according to the circuit configuration and driving method.

[0277] Here, the conductor 560 functions as the gate electrode of the transistor, and the conductors 542a and 542b function as the source electrode or the drain electrode, respectively. As described above, the conductor 560 is formed so as to be embedded in the opening of the insulator 580 and the region sandwiched between the conductor 542a and the conductor 542b. The arrangement of the conductor 560, the conductor 542a, and the conductor 542b is self-alignedly selected with respect to the opening of the insulator 580. That is, in the transistor 500, the gate electrode can be self-alignedly arranged between the source electrode and the drain electrode. Therefore, the conductor 560 can be formed without providing an alignment margin, so that the occupied area of the transistor 500 can be reduced. Thereby, miniaturization and high integration of the semiconductor device can be achieved.

[0278] Furthermore, since the conductor 560 is self-alignedly formed in the region between the conductor 542a and the conductor 542b, the conductor 560 does not have a region overlapping with the conductor 542a or the conductor 542b. Thereby, the parasitic capacitance formed between the conductor 560, the conductor 542a, and the conductor 542b can be reduced. Therefore, the switching speed of the transistor 500 can be improved, and high frequency characteristics can be achieved.

[0279] The conductor 560 may function as a first gate (also referred to as a top gate) electrode. Also, the conductor 503 may function as a second gate (also referred to as a bottom gate) electrode. In that case, the threshold voltage of the transistor 500 can be controlled by changing the potential applied to the conductor 503 independently without being linked to the potential applied to the conductor 560. In particular, by applying a negative potential to the conductor 503, the threshold voltage of the transistor 500 can be made greater than 0V, and the off-current can be reduced. Therefore, applying a negative potential to the conductor 503 can make the drain current smaller when the potential applied to the conductor 560 is 0V than when no negative potential is applied.

[0280] The conductor 503 is arranged to overlap with the oxide 530 and the conductor 560. Thereby, when a potential is applied to the conductor 560 and the conductor 503, the electric field generated from the conductor 560 and the electric field generated from the conductor 503 are connected, and can cover the channel formation region formed in the oxide 530. In this specification and the like, the structure of a transistor that electrically surrounds the channel formation region by the electric fields of the first gate electrode and the second gate electrode is called a surrounded channel (S-channel) structure.

[0281] Also, the conductor 503 has the same configuration as the conductor 518. The conductor 503a is formed in contact with the inner walls of the openings of the insulator 514 and the insulator 516, and the conductor 503b is further formed inside. Note that, in the transistor 500, the configuration in which the conductor 503a and the conductor 503b are laminated is shown, but the present invention is not limited to this. For example, the conductor 503 may be provided as a single layer or a laminated structure of three or more layers.

[0282] Here, it is preferable to use a conductive material in which the conductor 503a has a function of suppressing the diffusion of impurities such as hydrogen atoms, hydrogen molecules, water molecules, and copper atoms (the above impurities are difficult to permeate). Or, it is preferable to use a conductive material in which the conductor 503a has a function of suppressing the diffusion of oxygen (for example, at least one of oxygen atoms, oxygen molecules, etc.) (the above oxygen is difficult to permeate). Note that, in this specification, the function of suppressing the diffusion of impurities or oxygen means the function of suppressing the diffusion of any one or all of the above impurities or the above oxygen.

[0283] For example, by having the function of suppressing the diffusion of oxygen in the conductor 503a, it is possible to suppress the oxidation of the conductor 503b and the decrease in conductivity.

[0284] In addition, when the conductor 503 also serves as a wiring, the conductor 503b is preferably made of a highly conductive material mainly composed of tungsten, copper, or aluminum. In that case, the conductor 503a does not necessarily have to be provided. Although the conductor 503b is shown as a single layer, it may have a laminated structure. For example, it may be a laminate of titanium or titanium nitride and the above-mentioned conductive material.

[0285] The insulators 520, 522, and 524 have the function as a second gate insulating film.

[0286] Here, for the insulator 524 in contact with the oxide 530, it is preferable to use an insulator containing more oxygen than the oxygen that satisfies the stoichiometric composition. That is, it is preferable that an excess oxygen region is formed in the insulator 524. By providing such an insulator containing excess oxygen in contact with the oxide 530, oxygen vacancies in the oxide 530 can be reduced, and the reliability of the transistor 500 can be improved.

[0287] Specifically, as the insulator having an excess oxygen region, it is preferable to use an oxide material in which some oxygen desorbs by heating. The oxide that desorbs oxygen by heating means that in TDS (Thermal Desorption Spectroscopy) analysis, the desorption amount of oxygen in terms of oxygen atoms is 1.0×10 18 atoms / cm 3 or more, preferably 1.0×10 19 atoms / cm 3 or more, more preferably 2.0×10 19 atoms / cm 3 or more, or 3.0×10 20 atoms / cm 3 or more, and it is an oxide film. The surface temperature of the film during the above TDS analysis is preferably in the range of 100°C or more and 700°C or less, or 100°C or more and 400°C or less.

[0288] Also, when the insulator 524 has an excess oxygen region, it is preferable that the insulator 522 has a function of suppressing the diffusion of oxygen (for example, oxygen atoms, oxygen molecules, etc.) (the above oxygen is difficult to permeate).

[0289] It is preferable that the insulator 522 has a function of suppressing the diffusion of one or more of oxygen or impurities, so that the oxygen contained in the oxide 530 does not diffuse to the insulator 520 side. Further, it is possible to suppress the conductor 503 from reacting with the oxygen contained in the insulator 524 and the oxide 530.

[0290] The insulator 522 is preferably a single layer or a laminate of an insulator containing a so-called high-k material such as aluminum oxide, hafnium oxide, an oxide containing aluminum and hafnium (hafnium aluminate), tantalum oxide, zirconium oxide, lead zirconate titanate (PZT), strontium titanate (SrTiO 3 ), or (Ba,Sr)TiO 3 (BST). As the miniaturization and high integration of transistors progress, problems such as leakage current may occur due to the thinning of the gate insulating film. By using a high-k material for the insulator that functions as the gate insulating film, it is possible to reduce the gate potential during transistor operation while maintaining the physical film thickness.

[0291] In particular, it is advisable to use an insulator containing an oxide of one or both of aluminum and hafnium, which is an insulating material having a function of suppressing the diffusion of impurities and oxygen (the above oxygen is difficult to permeate). As the insulator containing an oxide of one or both of aluminum and hafnium, it is preferable to use aluminum oxide, hafnium oxide, an oxide containing aluminum and hafnium (hafnium aluminate), etc. When the insulator 522 is formed using such a material, the insulator 522 functions as a layer that suppresses the release of oxygen from the oxide 530 and the incorporation of impurities such as hydrogen from the peripheral portion of the transistor 500 into the oxide 530.

[0292] Alternatively, these insulators may be added with, for example, aluminum oxide, bismuth oxide, germanium oxide, niobium oxide, silicon oxide, titanium oxide, tungsten oxide, yttrium oxide, zirconium oxide. Or these insulators may be nitrided. Silicon oxide, silicon oxynitride or silicon nitride may be laminated on the above-mentioned insulators for use.

[0293] Also, the insulator 520 is preferably thermally stable. For example, silicon oxide and silicon oxynitride are suitable because they are thermally stable. Further, by combining an insulator of a high-k material with silicon oxide or silicon oxynitride, an insulator 520 having a laminated structure that is thermally stable and has a high relative dielectric constant can be obtained.

[0294] Note that in the transistors 500 of FIGS. 13A and 13B, the insulator 520, the insulator 522, and the insulator 524 are shown as a second gate insulating film having a three-layer laminated structure, but the second gate insulating film may have a single-layer, two-layer, or four-layer or more laminated structure. In that case, it is not limited to a laminated structure made of the same material, and a laminated structure made of different materials may also be used.

[0295] For the transistor 500, it is preferable to use a metal oxide that functions as an oxide semiconductor for the oxide 530 including the channel formation region. For example, as the oxide 530, a metal oxide such as In-M-Zn oxide (element M is selected from one or more of aluminum, gallium, yttrium, copper, vanadium, beryllium, boron, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, or magnesium, etc.) may be used.

[0296] Specifically, as the oxide 530a, a metal oxide with an atomic ratio of In:Ga:Zn = 1:3:4 or 1:1:0.5 may be used. As the oxide 530b, a metal oxide with an atomic ratio of In:Ga:Zn = 4:2:3 or 1:1:1 may be used. As the oxide 530c, a metal oxide with an atomic ratio of In:Ga:Zn = 1:3:4, Ga:Zn = 2:1, or Ga:Zn = 2:5 may be used. Specific examples of the case where the oxide 530c has a laminated structure include a laminated structure of In:Ga:Zn = 4:2:3 and In:Ga:Zn = 1:3:4, a laminated structure of Ga:Zn = 2:1 and In:Ga:Zn = 4:2:3, a laminated structure of Ga:Zn = 2:5 and In:Ga:Zn = 4:2:3, a laminated structure of gallium oxide and In:Ga:Zn = 4:2:3, etc.

[0297] Further, the oxide 530b may have crystallinity. For example, it is preferable to use CAAC-OS (c-axis aligned crystalline oxide semiconductor) described later. Oxides having crystallinity such as CAAC-OS have a dense structure with few impurities and defects (such as oxygen deficiency) and high crystallinity. Therefore, it is possible to suppress the extraction of oxygen from the oxide 530b by the source electrode or the drain electrode. In addition, even when heat treatment is performed, the extraction of oxygen from the oxide 530b can be reduced, so the transistor 500 is stable against a high temperature (so-called thermal budget) in the manufacturing process.

[0298] As the metal oxide that functions as the channel formation region in the oxide 530, it is preferable to use a metal oxide having a band gap of 2 eV or more, preferably 2.5 eV or more. By using a metal oxide having a large band gap in this way, the off-current of the transistor can be reduced.

[0299] By having the oxide 530a under the oxide 530b, the diffusion of impurities from the structure formed below the oxide 530a to the oxide 530b can be suppressed. Also, by having the oxide 530c on the oxide 530b, the diffusion of impurities from the structure formed above the oxide 530c to the oxide 530b can be suppressed.

[0300] Note that the oxide 530 preferably has a laminated structure of a plurality of oxide layers with different atomic ratios of each metal atom. Specifically, in the metal oxide used for the oxide 530a, the atomic ratio of the element M in the constituent elements is preferably larger than the atomic ratio of the element M in the constituent elements in the metal oxide used for the oxide 530b. Also, in the metal oxide used for the oxide 530a, the atomic ratio of the element M to In is preferably larger than the atomic ratio of the element M to In in the metal oxide used for the oxide 530b. Further, in the metal oxide used for the oxide 530b, the atomic ratio of In to the element M is preferably larger than the atomic ratio of In to the element M in the metal oxide used for the oxide 530a. Also, the oxide 530c can use the metal oxide that can be used for the oxide 530a or the oxide 530b.

[0301] Also, it is preferable that the energy of the lower end of the conduction band of the oxide 530a and the oxide 530c is higher than the energy of the lower end of the conduction band of the oxide 530b. In other words, it is preferable that the electron affinities of the oxide 530a and the oxide 530c are smaller than the electron affinity of the oxide 530b.

[0302] Here, at the junction of the oxide 530a, the oxide 530b, and the oxide 530c, the energy level of the lower end of the conduction band changes smoothly. In other words, it can also be said that the energy level of the lower end of the conduction band at the junction of the oxide 530a, the oxide 530b, and the oxide 530c changes continuously or is continuously joined. To achieve this, it is advisable to lower the density of defect levels in the mixed layer formed at the interface between the oxide 530a and the oxide 530b and at the interface between the oxide 530b and the oxide 530c.

[0303] Specifically, by having a common element other than oxygen (as the main component) between the oxide 530a and the oxide 530b, and between the oxide 530b and the oxide 530c, a mixed layer with a low density of defect levels can be formed. For example, when the oxide 530b is an In-Ga-Zn oxide, In-Ga-Zn oxide, Ga-Zn oxide, gallium oxide, etc. may be used as the oxide 530a and the oxide 530c.

[0304] At this time, the main path of carriers becomes the oxide 530b. By configuring the oxide 530a and the oxide 530c as described above, the density of defect levels at the interface between the oxide 530a and the oxide 530b and at the interface between the oxide 530b and the oxide 530c can be lowered. Therefore, the influence of interface scattering on carrier conduction is reduced, and the transistor 500 can obtain a high on-current.

[0305] On the oxide 530b, a conductor 542a and a conductor 542b that function as a source electrode and a drain electrode are provided. As the conductor 542a and the conductor 542b, a metal element selected from aluminum, chromium, copper, silver, gold, platinum, tantalum, nickel, titanium, molybdenum, tungsten, hafnium, vanadium, niobium, manganese, magnesium, zirconium, beryllium, indium, ruthenium, iridium, strontium, lanthanum, or an alloy containing the above-described metal element as a component, or an alloy combining the above-described metal elements, etc. are preferably used. For example, tantalum nitride, titanium nitride, tungsten, a nitride containing titanium and aluminum, a nitride containing tantalum and aluminum, ruthenium oxide, ruthenium nitride, an oxide containing strontium and ruthenium, an oxide containing lanthanum and nickel, etc. are preferably used. Further, metal nitride films such as tantalum nitride are preferable because they have a barrier property against hydrogen or oxygen.

[0306] Also, in FIG. 13A, the conductor 542a and the conductor 542b are shown as a single-layer structure, but a laminated structure of two or more layers may also be used. For example, a tantalum nitride film and a tungsten film may be laminated. Also, a titanium film and an aluminum film may be laminated. Further, a two-layer structure in which an aluminum film is laminated on a tungsten film, a two-layer structure in which a copper film is laminated on a copper-magnesium-aluminum alloy film, a two-layer structure in which a copper film is laminated on a titanium film, or a two-layer structure in which a copper film is laminated on a tungsten film may also be used.

[0307] In addition, there are three-layer structures such as a titanium film or a titanium nitride film, an aluminum film or a copper film laminated on the titanium film or the titanium nitride film, and further a titanium film or a titanium nitride film formed thereon, a molybdenum film or a molybdenum nitride film, an aluminum film or a copper film laminated on the molybdenum film or the molybdenum nitride film, and further a molybdenum film or a molybdenum nitride film formed thereon. Note that a transparent conductive material containing indium oxide, tin oxide, or zinc oxide may be used.

[0308] Also, as shown in FIG. 13A, in the interface between the oxide 530 and the conductor 542a (conductor 542b) and in the vicinity thereof, regions 543a and 543b may be formed as low-resistance regions. At this time, region 543a functions as one of the source region or the drain region, and region 543b functions as the other of the source region or the drain region. Further, a channel formation region is formed in the region sandwiched between region 543a and region 543b.

[0309] By providing the conductor 542a (conductor 542b) so as to be in contact with the oxide 530, the oxygen concentration in region 543a (region 543b) may be reduced. Further, a metal compound layer containing the metal contained in the conductor 542a (conductor 542b) and the components of the oxide 530 may be formed in region 543a (region 543b). In such a case, the carrier density in region 543a (region 543b) increases, and region 543a (region 543b) becomes a low-resistance region.

[0310] The insulator 544 is provided so as to cover the conductor 542a and the conductor 542b, and suppresses the oxidation of the conductor 542a and the conductor 542b. At this time, the insulator 544 may cover the side surface of the oxide 530 and be provided so as to be in contact with the insulator 524.

[0311] As the insulator 544, a metal oxide containing one or more selected from hafnium, aluminum, gallium, yttrium, zirconium, tungsten, titanium, tantalum, nickel, germanium, neodymium, lanthanum, magnesium, etc. can be used. Further, as the insulator 544, silicon oxynitride, silicon nitride, etc. can also be used.

[0312] In particular, as the insulator 544, it is preferable to use aluminum oxide, hafnium oxide, aluminum, and an oxide containing hafnium (hafnium aluminate), etc., which are insulators containing one or both oxides of aluminum or hafnium. In particular, hafnium aluminate has higher heat resistance than a hafnium oxide film. Therefore, it is preferable because it is difficult to crystallize in the heat treatment in a later process. Note that when the conductor 542a and the conductor 542b are made of a material having oxidation resistance or the conductivity does not significantly decrease even when oxygen is absorbed, the insulator 544 is not an essential component. It may be appropriately designed according to the required transistor characteristics.

[0313] By having the insulator 544, it is possible to suppress impurities such as water and hydrogen contained in the insulator 580 from diffusing to the oxide 530b through the oxide 530c and the insulator 550. Further, oxidation of the conductor 560 can be suppressed by the excess oxygen of the insulator 580.

[0314] The insulator 550 functions as a first gate insulating film. The insulator 550 is preferably disposed in contact with the inside (upper surface and side surface) of the oxide 530c. The insulator 550 is preferably formed using an insulator that contains an excessive amount of oxygen and releases oxygen by heating, similar to the above-described insulator 524.

[0315] Specifically, silicon oxide with excess oxygen, silicon oxynitride, silicon nitride oxide, silicon nitride, silicon oxide with fluorine added, silicon oxide with carbon added, silicon oxide with carbon and nitrogen added, and silicon oxide with pores can be used. In particular, silicon oxide and silicon oxynitride are preferable because they are stable against heat.

[0316] By providing an insulator that releases oxygen upon heating as insulator 550 in contact with the upper surface of oxide 530c, oxygen can be effectively supplied from insulator 550, through oxide 530c, to the channel formation region of oxide 530b. Also, similar to that in insulator 524, it is preferable that the concentration of impurities such as water or hydrogen in insulator 550 is reduced. The film thickness of insulator 550 is preferably 1 nm or more and 20 nm or less.

[0317] Further, in order to efficiently supply the excess oxygen possessed by insulator 550 to oxide 530, a metal oxide may be provided between insulator 550 and conductor 560. It is preferable that the metal oxide suppresses the diffusion of oxygen from insulator 550 to conductor 560. By providing a metal oxide that suppresses the diffusion of oxygen, the diffusion of excess oxygen from insulator 550 to conductor 560 is suppressed. That is, it is possible to suppress a decrease in the amount of excess oxygen supplied to oxide 530. Also, oxidation of conductor 560 by excess oxygen can be suppressed. As the metal oxide, a material that can be used for insulator 544 may be used.

[0318] Note that insulator 550 may have a laminated structure similar to that of the second gate insulating film. As the miniaturization and high integration of transistors progress, problems such as leakage current may occur due to the thinning of the gate insulating film. Therefore, by forming an insulator that functions as a gate insulating film into a laminated structure of a high-k material and a thermally stable material, it is possible to reduce the gate potential during transistor operation while maintaining the physical film thickness. Also, a laminated structure that is thermally stable and has a high relative dielectric constant can be formed.

[0319] The conductor 560 that functions as the first gate electrode is shown as a two-layer structure in FIGS. 13A and 13B, but it may also be a single-layer structure or a laminated structure of three or more layers.

[0320] For the conductor 560a, it is preferable to use a conductive material having a function of suppressing the diffusion of impurities such as hydrogen atoms, hydrogen molecules, water molecules, nitrogen atoms, nitrogen molecules, nitrogen oxide molecules (N 2 O, NO, NO 2 etc.), copper atoms, etc. Alternatively, it is preferable to use a conductive material having a function of suppressing the diffusion of oxygen (for example, at least one of oxygen atoms, oxygen molecules, etc.). By the conductor 560a having a function of suppressing the diffusion of oxygen, it is possible to suppress the oxidation of the conductor 560b by oxygen contained in the insulator 550 and the decrease in conductivity. As the conductive material having a function of suppressing the diffusion of oxygen, for example, it is preferable to use tantalum, tantalum nitride, ruthenium, or ruthenium oxide. Further, as the conductor 560a, an oxide semiconductor applicable to the oxide 530 can be used. In that case, by forming the conductor 560b by sputtering, the electrical resistance value of the conductor 560a can be decreased to make it a conductor. This can be called an OC (Oxide Conductor) electrode.

[0321] Also, for the conductor 560b, it is preferable to use a conductive material mainly composed of tungsten, copper, or aluminum. Further, since the conductor 560b also functions as a wiring, it is preferable to use a conductor having high conductivity. For example, a conductive material mainly composed of tungsten, copper, or aluminum can be used. Also, the conductor 560b may have a laminated structure, for example, a laminated structure of titanium or titanium nitride and the above conductive material.

[0322] Insulator 580 is provided on conductor 542a and conductor 542b via insulator 544. Insulator 580 preferably has an excess oxygen region. For example, as insulator 580, it is preferable to have silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, silicon oxide with added fluorine, silicon oxide with added carbon, silicon oxide with added carbon and nitrogen, silicon oxide with pores, or resin, etc. In particular, silicon oxide and silicon oxynitride are preferable because they are thermally stable. In particular, silicon oxide and silicon oxide with pores are preferable because an excess oxygen region can be easily formed in a later process.

[0323] Insulator 580 preferably has an excess oxygen region. By providing insulator 580 that releases oxygen upon heating in contact with oxide 530c, the oxygen in insulator 580 can be efficiently supplied to oxide 530 through oxide 530c. Note that it is preferable that the concentration of impurities such as water or hydrogen in insulator 580 is reduced.

[0324] The opening of insulator 580 is formed to overlap the region between conductor 542a and conductor 542b. Thereby, conductor 560 is formed to be embedded in the opening of insulator 580 and the region sandwiched between conductor 542a and conductor 542b.

[0325] When miniaturizing a semiconductor device, it is required to shorten the gate length, but it is necessary to prevent the conductivity of conductor 560 from decreasing. Therefore, if the film thickness of conductor 560 is increased, conductor 560 can have a high aspect ratio shape. In the present embodiment, since conductor 560 is provided to be embedded in the opening of insulator 580, even if conductor 560 has a high aspect ratio shape, it can be formed without collapsing conductor 560 during the process.

[0326] The insulator 574 is preferably provided in contact with the upper surface of the insulator 580, the upper surface of the conductor 560, and the upper surface of the insulator 550. By forming the insulator 574 by sputtering, an excess oxygen region can be provided in the insulator 550 and the insulator 580. Thereby, oxygen can be supplied from the excess oxygen region into the oxide 530.

[0327] For example, as the insulator 574, a metal oxide containing one or more selected from hafnium, aluminum, gallium, yttrium, zirconium, tungsten, titanium, tantalum, nickel, germanium, or magnesium can be used.

[0328] In particular, aluminum oxide has high barrier properties and can suppress the diffusion of hydrogen and nitrogen even in a thin film of 0.5 nm or more and 3.0 nm or less. Therefore, aluminum oxide formed by sputtering can function as an oxygen supply source and also as a barrier film for impurities such as hydrogen.

[0329] Also, it is preferable to provide an insulator 581 that functions as an interlayer film on the insulator 574. Similar to the insulator 524 and the like, the insulator 581 preferably has a reduced concentration of impurities such as water or hydrogen in the film.

[0330] Also, conductors 540a and 540b are arranged in openings formed in the insulator 581, the insulator 574, the insulator 580, and the insulator 544. The conductors 540a and 540b are provided to face each other with the conductor 560 interposed therebetween. The conductors 540a and 540b have the same configuration as the conductors 546 and 548 described later.

[0331] An insulator 582 is provided on an insulator 581. It is preferable to use a material that is barrier - like to one or more of oxygen and hydrogen for the insulator 582. Therefore, the same material as that of the insulator 514 can be used for the insulator 582. For example, it is preferable to use metal oxides such as aluminum oxide, hafnium oxide, and tantalum oxide for the insulator 582.

[0332] In particular, aluminum oxide has a high blocking effect of not allowing the film to permeate both oxygen and impurities such as hydrogen and moisture that are factors causing fluctuations in the electrical characteristics of the transistor. Therefore, aluminum oxide can prevent the mixing of impurities such as hydrogen and moisture into the transistor 500 during and after the manufacturing process of the transistor. Also, it can suppress the release of oxygen from the oxides constituting the transistor 500. Therefore, it is suitable for use as a protective film for the transistor 500.

[0333] Also, conductors 546, 548, etc. are embedded in the insulators 520, 522, 524, 544, 580, 574, 581, and 582. The conductors 546 and 548 have functions such as a plug connecting the conductor 610b and the transistor 300, or a wiring.

[0334] Conductors 546b, 548b, etc. are embedded in the insulators 580, 574, 581, and 582. The conductors 546b and 548b have functions such as a plug connecting to the conductors 542a, 542b, etc. of the transistor 500, or a wiring.

[0335] The conductors 546, 546b, 548, and 548b can be provided using the same materials as the conductors 328 and 330.

[0336] Subsequently, a conductor 610b is provided above the transistor 500. In the example shown in FIG. 1, the conductor 610b is provided on the insulator 582. In the example shown in FIG. 1, the conductor 610b is connected to the transistor 500 via the conductor 548b.

[0337] In addition to the conductor 610b, a conductor 610a may be provided on the insulator 582. For example, the conductor 610a can be formed by processing from the same conductive film as the conductor 610b. By providing an insulator 630 on the conductors 610a and 610b, and further providing a conductor 620 via the insulator 630 so as to overlap the conductor 610a, a capacitor element 600 composed of the conductor 610a, the conductor 620, and the insulator 630 can be provided on the insulator 582.

[0338] For the conductors 610a and 610b, a metal film containing an element selected from molybdenum, titanium, tantalum, tungsten, aluminum, copper, chromium, neodymium, scandium, or a metal nitride film (tantalum nitride film, titanium nitride film, molybdenum nitride film, tungsten nitride film) composed of the above-described elements can be used. Alternatively, a conductive material such as indium tin oxide, indium oxide containing tungsten oxide, indium zinc oxide containing tungsten oxide, indium oxide containing titanium oxide, indium tin oxide containing titanium oxide, indium zinc oxide, indium tin oxide added with silicon oxide can also be applied.

[0339] In FIG. 8, the conductors 610a and 610b are shown in a single-layer structure, but the present invention is not limited to this configuration, and a laminated structure of two or more layers may be used. For example, a conductor having a barrier property, and a conductor having high conductivity and high adhesion to the conductor having high conductivity may be formed between the conductor having a barrier property and the conductor having high conductivity.

[0340] The conductor 620 can be made of a conductive material such as a metal material, an alloy material, or a metal oxide material. It is preferable to use a high melting point material such as tungsten or molybdenum that combines heat resistance and conductivity, and it is particularly preferable to use tungsten. Also, when forming simultaneously with other structures such as the conductor, a low-resistance metal material such as Cu (copper) or Al (aluminum) may be used.

[0341] An insulator 640 is provided on the conductor 620 and the insulator 630. The insulator 640 can be provided using the same material as the insulator 320. Also, the insulator 640 may function as a planarization film that covers the uneven shape below it.

[0342] In the semiconductor device shown in FIG. 8, a conductor 631 is provided so as to be embedded in the insulator 640, and a conductor 632 is further provided on the conductor 631. The conductor 631 can function as a plug that is electrically connected to the transistor 300(1). Also, the conductor 632 is electrically connected to the transistor 300(1) via the conductor 631.

[0343] FIG. 8 shows an example of a semiconductor device configured on a substrate 311. The conductor 632 has a function as an electrode pad for connecting, for example, a circuit provided on a chip different from the configuration provided on the substrate 311, and a bump, wire bonding, clip bonding, etc.

[0344] FIG. 14 shows an example of arranging the semiconductor device shown in FIG. 8 on a printed circuit board 638 via bumps 637. In FIG. 14, the surface of the semiconductor device shown in FIG. 8 where the conductor 632 is exposed and the printed circuit board 638 are arranged to face each other via the bumps 637. Also, a resin layer 641 may be provided on the back electrode 318 to maintain strength.

[0345] FIG. 15 shows an example in which the semiconductor device shown in FIG. 8 is disposed on a printed circuit board 638 and conductors 632 and other chips are connected by wire bonding. In FIG. 15, in the semiconductor device shown in FIG. 8, the semiconductor device is disposed on the printed circuit board 638 with the surface on which the conductor 632 is exposed as the upper surface. The surface on which the back electrode 318 is provided and the printed circuit board 638 are disposed so as to face each other via a resin layer 639. A wire 642 is bonded to the conductor 632.

[0346] Here, by providing the conductor 632 so as to overlap with a conductor connected to a low-resistance region (for example, the low-resistance region 314a or the low-resistance region 314b) of the transistor 300, the routing of the conductor between the transistor 300 and the conductor 632 can be shortened, and the resistance between the transistor 300(1) and the conductor 632 can be reduced. More specifically, for example, as shown in FIG. 1, it is preferable to provide the conductor 632 so as to overlap at least one of the conductor 328b and the conductor 328. Further, it is preferable that the conductors 356 and 518 are each provided so as to at least partially overlap with the conductor 632.

[0347] Since the resistance can be reduced by shortening the routing of the conductor between the transistor 300 and the conductor 632, for example, in the semiconductor device shown in FIG. 8, the thicknesses of the conductors provided in each wiring, more specifically, for example, the insulators 326, 354, 516, etc., and the conductor 632 can be made thinner. Therefore, in the semiconductor device shown in FIG. 8, miniaturization of the semiconductor element becomes possible.

[0348] In the power storage device according to one aspect of the present invention, a large-capacity battery pack may be connected. Further, in the battery pack connected to the power storage device according to one aspect of the present invention, rapid charging, rapid discharging, etc. may be performed. Therefore, a large current may flow through the transistor 300.

[0349] When a large current flows through the transistor 300, the amount of heat generated by the transistor 300 may increase. In the OS transistor, fluctuations in characteristics with respect to temperature changes can be suppressed. Therefore, by using the OS transistor as the transistor 500, even when the amount of heat generated by the transistor 300 increases, the semiconductor device can operate stably.

[0350] The configuration shown in FIG. 12 provides, as a first structure, a layer 585 having a transistor 500 on a substrate 311b, conductors 610b, 631, etc. on the layer 585, an insulator 901 and a conductor 632 provided so as to be embedded in the insulator 901 on the conductor 631, etc., and as a second structure, a configuration having a layer 385, and instead of the insulator 322 of the layer 385, a laminated structure of the insulator 322 and an insulator 902 on the insulator 322, and has a configuration in which the first structure and the second structure are bonded together.

[0351] An example of a manufacturing method of the configuration shown in FIG. 12 will be described with reference to FIGS. 16 to 18.

[0352] First, as shown in FIG. 16A, transistors 300(1) and 300(2) are provided on a substrate 311. The conductor 328 provided on the low-resistance region such as the transistor 300(1) is provided so as to be embedded in the insulators 320, 322, and 902.

[0353] The insulator 902 and the conductor 328 have a function as a bonding surface.

[0354] Next, as shown in FIG. 16B, an insulator 322b is provided on a substrate 311b. For the substrate 311b, the description of the substrate 311 can be referred to. For the insulator 322b, the description of the insulator 322 can be referred to.

[0355] Next, on the insulator 322, a structure from the insulator 324 shown in FIG. 8 is provided on the upper part. Then, on the conductor 631 or the like, an insulator 901 and a conductor 632 provided so as to be embedded in the insulator 901 are provided.

[0356] Next, as shown in FIG. 17, the surfaces where the insulator 901 and the conductor 632 are exposed and the surfaces where the insulator 902 and the conductor 328 are exposed are bonded together.

[0357] Next, as shown in FIG. 18, the substrate 311 is polished to make it thinner. Then, a low-resistance region 317 is provided on the polished surface of the substrate 311. Then, the back electrode 318 is formed.

[0358] By polishing and thinning the substrate 311, the distances between the low-resistance regions 314a, 314b, etc. and the low-resistance region 317 can be shortened, and in the transistors 300(1) and 300(2), the resistance between the source and the drain can be reduced.

[0359] Also, in the configuration shown in FIG. 18, even when the substrate 311 is polished and thinned, when combined with the thickness of the substrate 311b, it has a sufficient thickness, so the strength of the semiconductor device can be maintained.

[0360] Then, a conductor 903 is provided so as to penetrate the substrate 311b and the insulator 322b, and the configuration of the semiconductor device shown in FIG. 12 is obtained. Note that the conductor 903 may be provided before the bonding. Also, before providing the conductor 903, the substrate 311b may be polished and thinned.

[0361] Also, in FIG. 18, in the semiconductor device, the surface where the conductor 903 is exposed and the printed circuit board 638 are arranged so as to face each other via the bump 637. Also, as shown in FIG. 18, it is preferable to further provide a conductor 903b on the conductor 903.

[0362] Here, it is preferable that the main components of the conductor 328 and the conductor 632 are the same metal element. Also, it is preferable that the insulator 901 and the insulator 902 are composed of the same components.

[0363] For example, for the conductor 328 and the conductor 632, Cu, Al, Sn, Zn, W, Ag, Pt, Au, etc. can be used. From the viewpoint of ease of bonding, it is preferably Cu, Al, W, or Au. Also, for the insulator 901 and the insulator 902, silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, titanium nitride, etc. can be used.

[0364] That is, it is preferable to use the same metal material shown above for each of the conductor 328 and the conductor 632. Also, it is preferable to use the same insulating material shown above for each of the insulator 901 and the insulator 902. With such a configuration, the bonding can be performed with good yield.

[0365] Note that the conductor 328 and the conductor 632 may have a multilayer structure of multiple layers. In that case, it is sufficient that the surface layer (bonding surface) is the same metal material. Also, the insulator 901 and the insulator 902 may also have a multilayer structure of multiple layers. In that case, it is sufficient that the surface layer (bonding surface) is the same insulating material.

[0366] By such bonding, good electrical connection between the conductor 328 and the conductor 632 can be obtained. Also, a connection having sufficient mechanical strength of the insulator 901 and the insulator 902 can be obtained.

[0367] For the bonding between metal layers, a surface activation bonding method can be used in which the oxide film on the surface and the adsorbed layer of impurities are removed by sputtering treatment or the like, and the cleaned and activated surfaces are brought into contact and bonded. Alternatively, a diffusion bonding method in which the surfaces are bonded by using a combination of temperature and pressure can be used. Since bonding occurs at the atomic level in both cases, excellent bonding can be obtained not only electrically but also mechanically.

[0368] In addition, for the bonding between insulating layers, after obtaining high flatness by polishing or the like, hydrophilic surfaces obtained by hydrophilic treatment with oxygen plasma or the like are brought into contact with each other for temporary bonding, and a hydrophilic bonding method such as performing permanent bonding by dehydration through heat treatment can be used. Since the hydrophilic bonding method also causes bonding at the atomic level, a mechanically excellent bond can be obtained.

[0369] Since the bonding surface of the bonding includes a mixture of an insulating layer and a metal layer, for example, a surface activation bonding method and a hydrophilic bonding method may be combined and performed.

[0370] For example, a method such as cleaning the surface after polishing, performing an antioxidant treatment on the surface of the metal layer, and then performing a hydrophilic treatment for bonding can be used. Further, the surface of the metal layer may be made of a metal with poor oxidation resistance such as Au, and a hydrophilic treatment may be performed. In addition, a bonding method other than the methods described above may be used.

[0371] By using this structure, in a semiconductor device using a transistor having an oxide semiconductor, fluctuations in electrical characteristics can be suppressed and reliability can be improved. Alternatively, in a battery control circuit using a transistor having an oxide semiconductor, miniaturization or high integration can be achieved.

[0372] Figures 8, 9, and 10A show examples of D-MOSFETs in which transistors 300(1) and 300(2) have a planar structure, while Figure 10B shows an example of a D-MOSFET in which transistors 300(1) and transistor (2) have a trench structure. In Figure 10B, a conductor 316 that functions as a gate is formed in a trench provided between a low-resistance region 314a and a low-resistance region 314b. An insulator 315 that functions as a gate insulator is formed between the low-resistance region 314a and the low-resistance region 314b and the conductor 316.

[0373] In FIG. 10B, examples are shown in which electrodes such as the conductor 328b and the conductor 328, and plugs are electrically connected to the low-resistance region 314a and the low-resistance region 314b, respectively. In the example shown in FIG. 10C, an example is shown in which the conductor 328c is electrically connected to a plurality of low-resistance regions. The conductor 328c preferably has a shape that covers at least a part of each of the plurality of low-resistance regions. Further, the conductor 328c preferably overlaps at least a part of each of the plurality of low-resistance regions. An insulator 320 is provided on the conductor 316, and the insulator 320 has a function of separating conduction between the conductor 316 and the conductor 328c.

[0374] Compared with the planar structure, in the trench structure, the area of the integrated circuit is preferably reduced to 0.5 times or less, and more preferably reduced to 0.4 times or less.

[0375] This embodiment can be appropriately combined with the descriptions of other embodiments.

[0376] (Embodiment 5) In this embodiment, a metal oxide according to one aspect of the present invention will be described.

[0377] [[Metal Oxide]] As the oxide 530, it is preferable to use a metal oxide that functions as an oxide semiconductor. Hereinafter, the metal oxide applicable to the oxide 530 according to the present invention will be described.

[0378] The metal oxide preferably contains at least indium or zinc. In particular, it preferably contains indium and zinc. In addition to these, it is preferable that gallium, yttrium, tin, etc. are contained. Further, one or more selected from boron, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, magnesium, etc. may be contained.

[0379] Here, consider the case where the metal oxide is an In-M-Zn oxide having indium, element M, and zinc. Note that element M is aluminum, gallium, yttrium, or tin. Other elements applicable as element M include boron, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, magnesium, and the like. However, there may be cases where a plurality of the aforementioned elements are combined as element M.

[0380] Note that in this specification and the like, a metal oxide having nitrogen may also be collectively referred to as a metal oxide. Further, a metal oxide having nitrogen may be referred to as a metal oxynitride.

[0381] [Structure of Metal Oxide] Oxide semiconductors (metal oxides) can be divided into single-crystalline oxide semiconductors and other non-single-crystalline oxide semiconductors. Examples of non-single-crystalline oxide semiconductors include CAAC-OS, polycrystalline oxide semiconductors, nc-OS (nanocrystalline oxide semiconductor), pseudo-amorphous oxide semiconductors (a-like OS: amorphous-like oxide semiconductor), and amorphous oxide semiconductors.

[0382] CAAC-OS has a c-axis orientation, and a plurality of nanocrystals are connected in the a-b plane direction, resulting in a crystal structure having strain. Note that the strain refers to a portion where the direction of the lattice arrangement changes between a region where the lattice arrangements are aligned and another region where the lattice arrangements are aligned in the region where the plurality of nanocrystals are connected.

[0383] The nanocrystals are based on a hexagon, but are not necessarily regular hexagons and may be non-regular hexagons. Also, in the case of strain, there may be lattice arrays such as pentagons and heptagons. In CAAC-OS, it is difficult to confirm a clear grain boundary (also referred to as a grain boundary) even in the vicinity of strain. That is, it can be seen that the formation of grain boundaries is suppressed by the strain of the lattice array. This is because CAAC-OS can tolerate strain due to the fact that the arrangement of oxygen atoms is not dense in the a-b plane direction and the interatomic bond distance changes due to the substitution of metal elements.

[0384] In addition, CAAC-OS tends to have a layered crystal structure (also referred to as a layered structure) in which a layer containing indium and oxygen (hereinafter referred to as an In layer) and a layer containing element M, zinc, and oxygen (hereinafter referred to as an (M,Zn) layer) are laminated. Note that indium and element M are mutually substitutable, and when element M in the (M,Zn) layer is substituted with indium, it can also be represented as an (In,M,Zn) layer. Also, when indium in the In layer is substituted with element M, it can also be represented as an (In,M) layer.

[0385] CAAC-OS is a highly crystalline metal oxide. On the other hand, since it is difficult to confirm a clear grain boundary in CAAC-OS, it can be said that a decrease in electron mobility due to grain boundaries is unlikely to occur. Also, since the crystallinity of metal oxides may decrease due to the incorporation of impurities and the generation of defects, it can be said that CAAC-OS is a metal oxide with few impurities and defects (such as oxygen deficiencies). Therefore, the physical properties of the metal oxide having CAAC-OS are stable. For this reason, the metal oxide having CAAC-OS is heat-resistant and highly reliable.

[0386] nc-OS has periodicity in the atomic arrangement in a minute region (for example, a region of 1 nm or more and 10 nm or less, particularly a region of 1 nm or more and 3 nm or less). Further, nc-OS has no regularity in the crystal orientation among different nanocrystals. Therefore, no orientation is observed in the whole film. Thus, depending on the analysis method, nc-OS may not be distinguishable from a-like OS or an amorphous oxide semiconductor.

[0387] Note that indium-gallium-zinc oxide (hereinafter, IGZO), which is a kind of metal oxide having indium, gallium, and zinc, may take a stable structure by using the above-described nanocrystals. In particular, since IGZO tends to be difficult to grow crystals in the air, it may be structurally more stable to use crystals smaller than large crystals (here, crystals of several mm or crystals of several cm) (for example, the above-described nanocrystals).

[0388] a-like OS is a metal oxide having a structure between nc-OS and an amorphous oxide semiconductor. a-like OS has a loose or low-density region. That is, a-like OS has lower crystallinity than nc-OS and CAAC-OS.

[0389] Oxide semiconductors (metal oxides) have various structures and each has different characteristics. The oxide semiconductor according to one aspect of the present invention may have two or more of an amorphous oxide semiconductor, a polycrystalline oxide semiconductor, a-like OS, nc-OS, and CAAC-OS.

[0390] [Impurities] Here, the influence of each impurity in the metal oxide will be described.

[0391] When an impurity is mixed into an oxide semiconductor, a defect level or an oxygen deficiency may be formed. Therefore, when an impurity is mixed into the channel formation region of the oxide semiconductor, the electrical characteristics of a transistor using the oxide semiconductor are likely to vary and the reliability may be lowered. Further, when the channel formation region contains an oxygen deficiency, the transistor tends to have normally-on characteristics.

[0392] In addition, the above-mentioned defect levels may include trap levels. The charges trapped in the trap levels of the metal oxide may take a long time to disappear and may behave like fixed charges. Therefore, a transistor having a metal oxide with a high trap level density in the channel formation region may have unstable electrical characteristics.

[0393] In addition, when impurities are present in the channel formation region of the oxide semiconductor, the crystallinity of the channel formation region may be lowered, and the crystallinity of the oxide provided in contact with the channel formation region may also be lowered. When the crystallinity of the channel formation region is low, the stability or reliability of the transistor tends to decrease. In addition, when the crystallinity of the oxide provided in contact with the channel formation region is low, interface levels may be formed, and the stability or reliability of the transistor may decrease.

[0394] Therefore, in order to improve the stability or reliability of the transistor, it is effective to reduce the impurity concentration in the channel formation region of the oxide semiconductor and in the vicinity thereof. Examples of the impurities include hydrogen, nitrogen, alkali metals, alkaline earth metals, iron, nickel, and silicon.

[0395] Specifically, in the channel formation region of the oxide semiconductor and in the vicinity thereof, the concentration of the above-mentioned impurities obtained by secondary ion mass spectrometry (SIMS) is 1×10 18 atoms / cm 3 or less, preferably 2×10 16 atoms / cm 3Make it as follows. Alternatively, in the channel formation region of the oxide semiconductor and its vicinity, the concentration of the above-described impurity obtained by elemental analysis using EDX is made 1.0 atomic% or less. When an oxide containing element M is used as the oxide semiconductor, in the channel formation region of the oxide semiconductor and its vicinity, the concentration ratio of the above-described impurity to element M is made less than 0.10, preferably less than 0.05. Here, the concentration of element M used when calculating the above-described concentration ratio may be the concentration in the same region as the region where the concentration of the above-described impurity is calculated, or may be the concentration in the oxide semiconductor.

[0396] In addition, since a metal oxide with a reduced impurity concentration has a low defect level density, the trap level density may also be low.

[0397] In addition, when hydrogen enters the oxygen deficiency in the metal oxide, oxygen deficiency and hydrogen may combine to form V O H. V O H functions as a donor and electrons that are carriers may be generated. In addition, part of the hydrogen may combine with oxygen that binds to a metal atom to generate electrons that are carriers.

[0398] Therefore, a transistor using an oxide semiconductor containing a large amount of hydrogen tends to have normally-on characteristics. In addition, since hydrogen in the oxide semiconductor is likely to move due to stress such as heat and an electric field, if the oxide semiconductor contains a large amount of hydrogen, the reliability of the transistor may decrease.

[0399] That is, it is preferable to reduce V O H in the metal oxide as much as possible to make it highly pure intrinsic or substantially highly pure intrinsic. Thus, in order to obtain an oxide semiconductor in which V O H is sufficiently reduced, it is important to remove impurities such as moisture and hydrogen in the oxide semiconductor (which may be described as dehydration and dehydrogenation treatment), and to supply oxygen to the oxide semiconductor to compensate for oxygen deficiency (which may be described as oxygen addition treatment). V OBy using an oxide semiconductor with sufficiently reduced impurities such as H in the channel formation region of a transistor, stable electrical characteristics can be imparted.

[0400] In addition, it is preferable to use an oxide semiconductor with a low carrier concentration for the transistor. When reducing the carrier concentration of the oxide semiconductor, the impurity concentration in the oxide semiconductor may be reduced and the density of defect levels may be reduced. In this specification and the like, a low impurity concentration and a low density of defect levels are referred to as high-purity intrinsic or substantially high-purity intrinsic. Note that examples of impurities in the oxide semiconductor include hydrogen, nitrogen, alkali metals, alkaline earth metals, iron, nickel, silicon, and the like.

[0401] In particular, hydrogen contained in the oxide semiconductor may react with oxygen bonded to metal atoms to form water, and thus oxygen vacancies may be formed in the oxide semiconductor. When the channel formation region in the oxide semiconductor contains oxygen vacancies, the transistor may have normally-on characteristics. Furthermore, defects in which hydrogen enters oxygen vacancies may function as donors, and electrons serving as carriers may be generated. In addition, a part of hydrogen may bond to oxygen bonded to metal atoms to generate electrons serving as carriers. Therefore, a transistor using an oxide semiconductor containing a large amount of hydrogen is likely to have normally-on characteristics.

[0402] Defects (V O H) in which hydrogen enters oxygen vacancies may function as donors in the oxide semiconductor. However, it is difficult to quantitatively evaluate such defects. Therefore, in the oxide semiconductor, it may be evaluated by the carrier concentration instead of the donor concentration. Thus, in this specification and the like, as a parameter of the oxide semiconductor, the carrier concentration assuming a state where no electric field is applied may be used instead of the donor concentration. That is, the "carrier concentration" described in this specification and the like may be paraphrased as the "donor concentration" in some cases.

[0403] Therefore, it is preferable that hydrogen in the oxide semiconductor is reduced as much as possible. Specifically, in the oxide semiconductor, the hydrogen concentration obtained by SIMS is 1×10 20 atoms / cm 3 less than, preferably 1×10 19 atoms / cm 3 less than, more preferably 5×10 18 atoms / cm 3 less than, still more preferably 1×10 18 atoms / cm 3 less than. By using an oxide semiconductor in which impurities such as hydrogen are sufficiently reduced in the channel formation region of the transistor, stable electrical characteristics can be imparted.

[0404] In addition, the carrier concentration of the oxide semiconductor in the channel formation region is preferably 1×10 18 cm -3 or less, more preferably 1×10 17 cm -3 less than, still more preferably 1×10 16 cm -3 less than, still more preferably 1×10 13 cm -3 less than, still more preferably 1×10 12 cm -3 less than, still more preferably 1×10 -9 cm -3 or less. Note that the lower limit value of the carrier concentration of the oxide semiconductor in the channel formation region is not particularly limited, and for example, it can be 1×10 -9 cm -3 .

[0405] According to one aspect of the present invention, a semiconductor device with good reliability can be provided. Further, according to one aspect of the present invention, a semiconductor device having good electrical characteristics can be provided. Further, according to one aspect of the present invention, a semiconductor device with a large on-current can be provided. Further, according to one aspect of the present invention, a semiconductor device capable of miniaturization or high integration can be provided. Further, one aspect of the present invention aims to provide a low-power consumption semiconductor device.

[0406] <<Other semiconductor materials>> The semiconductor materials that can be used for the oxide 530 are not limited to the above-described metal oxides. As the oxide 530, a semiconductor material having a band gap (a semiconductor material that is not a zero-gap semiconductor) may be used. For example, it is preferable to use a single-element semiconductor such as silicon, a compound semiconductor such as gallium arsenide, or a layer-like substance that functions as a semiconductor (also referred to as an atomic layer substance, a two-dimensional material, etc.) as the semiconductor material. In particular, it is suitable to use a layer-like substance that functions as a semiconductor as the semiconductor material.

[0407] Here, in this specification and the like, the layer-like substance is a general term for a group of materials having a layered crystal structure. The layered crystal structure is a structure in which layers formed by covalent bonds or ionic bonds are stacked via a bond weaker than covalent bonds or ionic bonds, such as van der Waals forces. The layer-like substance has high electrical conductivity within a unit layer, that is, high two-dimensional electrical conductivity. By using a material that functions as a semiconductor and has high two-dimensional electrical conductivity in the channel formation region, a transistor with a large on-current can be provided.

[0408] Examples of the layer-like substance include graphene, silicene, and chalcogenides. A chalcogenide is a compound containing a chalcogen. Further, chalcogen is a general term for elements belonging to Group 16, and includes oxygen, sulfur, selenium, tellurium, polonium, and livermorium. Examples of the chalcogenide include transition metal chalcogenides and Group 13 chalcogenides.

[0409] As the oxide 530, for example, it is preferable to use a transition metal chalcogenide that functions as a semiconductor. Specific examples of the transition metal chalcogenide applicable as the oxide 530 include molybdenum sulfide (typically MoS 2 ), molybdenum selenide (typically MoSe 2 ), molybdenum telluride (typically MoTe 2 ), tungsten sulfide (typically WS 2 ), tungsten selenide (typically WSe 2) Tungsten telluride (typically WTe 2 ) Hafnium sulfide (typically HfS 2 ) Hafnium selenide (typically HfSe 2 ) Zirconium sulfide (typically ZrS 2 ) Zirconium selenide (typically ZrSe 2 ) and the like.

[0410] This embodiment can be appropriately combined with the descriptions of other embodiments.

[0411] (Embodiment 6) In this embodiment, an example in which the battery control circuit described in the above embodiment is used as an electronic component will be described with reference to FIG. 19.

[0412] In this embodiment, an example of a chip 1204 on which the semiconductor device of the present invention is mounted is shown with reference to FIG. 19. A plurality of circuits (systems) are mounted on the chip 1204. In this way, the technology of integrating a plurality of circuits (systems) on one chip is sometimes called System on Chip (SoC).

[0413] FIG. 19 shows an example in which a plurality of chips are provided on a printed circuit board (PCB) 1203. In FIG. 19, a circuit 1201 is provided on the printed circuit board 1203. A battery control circuit according to one aspect of the present invention is provided in the circuit 1201. A plurality of bumps 1202 are provided on the back surface of the circuit 1201 and are connected to the printed circuit board 1203.

[0414] By providing a battery control circuit using the configuration of the semiconductor device according to one aspect of the present invention, a plurality of circuits can be provided on the same chip. By providing a battery control circuit using the configuration of the semiconductor device according to one aspect of the present invention, the number of chips can be reduced in an electronic component. For example, the circuit 101a and the circuit 101b shown in the previous embodiment can be provided on the same chip.

[0415] By reducing the number of chips, circuit operation can be stably performed even in a vibrating environment. Further, by using bumps to mechanically and firmly connect the chip to the connection electrodes of the printed circuit board and ensuring electrical connection, a configuration that is more resistant to vibration can be achieved. Therefore, for example, it is suitable for electronic components mounted on vehicles.

[0416] Also, by providing a battery control circuit using the configuration of the semiconductor device according to one aspect of the present invention, chip integration becomes possible. Thus, in a portable terminal and various other electronic devices, the occupied volume of the battery control circuit can be reduced, enabling miniaturization of the electronic device. Also, due to the miniaturization of the control circuit, the volume occupied by the battery can be increased. Thereby, the duration of the storage battery can be extended. Also, in some cases, power consumption can be reduced due to the miniaturization of the control circuit.

[0417] It is preferable that an integrated circuit 1223 is provided on the printed circuit board 1203 as a second circuit. The integrated circuit 1223 has a function of supplying a control signal, power supply, etc. to the circuit 1201.

[0418] As various circuits provided on the printed circuit board 1203, storage devices such as a DRAM 1221 and a flash memory 1222 may be provided. Also, a circuit 1225 may be provided on the printed circuit board 1203 as a circuit having a function of performing wireless communication.

[0419] Also, the integrated circuit 1223 may have one or more of a function of performing image processing and a function of performing a multiply-accumulate operation.

[0420] Also, the integrated circuit 1223 may have an analog arithmetic unit. The analog arithmetic unit may have one or both of an A / D (analog / digital) conversion circuit and a D / A (digital / analog) conversion circuit.

[0421] This embodiment can be appropriately combined with the descriptions of other embodiments.

[0422] (Embodiment 7) In this embodiment, a configuration of a power storage device to which an electronic component including the battery control circuit described in the above embodiment can be applied will be described.

[0423] [Cylindrical secondary battery] An example of a cylindrical secondary battery will be described with reference to FIG. 20A. As shown in FIG. 20A, the cylindrical secondary battery 400 has a positive electrode cap (battery lid) 401 on the upper surface and a battery can (outer can) 402 on the side surface and the bottom surface. The positive electrode cap 401 and the battery can (outer can) 402 are insulated from each other by a gasket (insulating packing) 410.

[0424] FIG. 20B is a diagram schematically showing a cross section of the cylindrical secondary battery. The cylindrical secondary battery shown in FIG. 20B has a positive electrode cap (battery lid) 401 on the upper surface and a battery can (outer can) 402 on the side surface and the bottom surface. The positive electrode cap and the battery can (outer can) 402 are insulated from each other by a gasket (insulating packing) 410.

[0425] Inside the hollow cylindrical battery can 402, a battery element in which a strip-shaped positive electrode 604 and a negative electrode 606 are wound with a separator 605 interposed therebetween is provided. Although not shown, the battery element is wound around a center pin. One end of the battery can 402 is closed and the other end is open. For the battery can 402, a metal such as nickel, aluminum, titanium, or an alloy thereof, or an alloy of these and another metal (for example, stainless steel, etc.) that is corrosion-resistant to the electrolytic solution can be used. Further, in order to prevent corrosion by the electrolytic solution, it is preferable to coat the battery can 402 with nickel, aluminum, etc. Inside the battery can 402 where the positive electrode, negative electrode, and separator are wound, the battery element is sandwiched between a pair of opposing insulating plates 608 and 609. Further, a non-aqueous electrolytic solution (not shown) is injected into the inside of the battery can 402 in which the battery element is provided. The non-aqueous electrolytic solution can be the same as that used for the coin-type secondary battery.

[0426] Since the positive and negative electrodes used in the cylindrical storage battery are wound, it is preferable to form the active material on both sides of the current collector. A positive electrode terminal (positive current collector lead) 603 is connected to the positive electrode 604, and a negative electrode terminal (negative current collector lead) 607 is connected to the negative electrode 606. Both the positive electrode terminal 603 and the negative electrode terminal 607 can use a metal material such as aluminum. The positive electrode terminal 603 is resistance welded to the safety valve mechanism 613, and the negative electrode terminal 607 is resistance welded to the bottom of the battery can 402. The safety valve mechanism 613 is electrically connected to the positive electrode cap 401 via a PTC (Positive Temperature Coefficient) element 611. The safety valve mechanism 613 disconnects the electrical connection between the positive electrode cap 401 and the positive electrode 604 when the internal pressure of the battery rises beyond a predetermined threshold. Also, the PTC element 611 is a thermal sensing resistor element whose resistance increases when the temperature rises, and it restricts the current amount due to the increase in resistance to prevent abnormal heat generation. For the PTC element, barium titanate (BaTiO 3 )-based semiconductor ceramics or the like can be used.

[0427] FIG. 20C shows an example of the power storage device 415. The power storage device 415 has a plurality of secondary batteries 400. The positive electrodes of the respective secondary batteries are in contact with and electrically connected to a conductor 424 separated by an insulator 425. The conductor 424 is electrically connected to the control circuit 420 via a wiring 423. Also, the negative electrodes of the respective secondary batteries are electrically connected to the control circuit 420 via a wiring 426. As the control circuit 420, the battery control circuit described in the previous embodiment can be used.

[0428] FIG. 20D shows an example of the power storage device 415. The power storage device 415 has a plurality of secondary batteries 400, and the plurality of secondary batteries 400 are sandwiched between a conductive plate 413 and a conductive plate 414. The plurality of secondary batteries 400 are electrically connected to the conductive plate 413 and the conductive plate 414 by a wiring 416. The plurality of secondary batteries 400 may be connected in parallel, may be connected in series, or may be connected in parallel and then further connected in series. By configuring the power storage device 415 having a plurality of secondary batteries 400, a large amount of power can be extracted.

[0429]

[0429] Consider a case where a plurality of secondary batteries 400 are connected in parallel and then further connected in series. In such a case, in the power storage device shown in FIG. 1 or FIG. 2, for example, the battery cell 121 corresponds to a plurality of secondary batteries connected in parallel, and one cell balance circuit 130 is electrically connected to the plurality of secondary batteries connected in parallel.

[0430]

[0430] A temperature control device may be provided between the plurality of secondary batteries 400. When the secondary battery 400 is overheated, it can be cooled by the temperature control device, and when the secondary battery 400 is too cold, it can be heated by the temperature control device. Therefore, the performance of the power storage device 415 is less affected by the outside air temperature.

[0431]

[0431] Also, in FIG. 20D, the power storage device 415 is electrically connected to the control circuit 420 via the wiring 421 and the wiring 422. As the control circuit 420, the battery control circuit described in the previous embodiment can be used. The wiring 421 is electrically connected to the positive electrodes of the plurality of secondary batteries 400 via the conductive plate 413, and the wiring 422 is electrically connected to the negative electrodes of the plurality of secondary batteries 400 via the conductive plate 414.

[0432]

[0432] Moreover, a secondary battery 913 having a wound body 950a as shown in FIGS. 30A to 30C may be used. The wound body 950a shown in FIG. 30A has a negative electrode 931, a positive electrode 932, and a separator 933. The negative electrode 931 has a negative electrode active material layer 931a. The positive electrode 932 has a positive electrode active material layer 932a. The separator 933 has a width wider than that of the negative electrode active material layer 931a and the positive electrode active material layer 932a, and is wound so as to overlap the negative electrode active material layer 931a and the positive electrode active material layer 932a. Also, it is preferable in terms of safety that the width of the negative electrode active material layer 931a is wider than that of the positive electrode active material layer 932a. Moreover, a wound body 950a having such a shape is preferable in terms of safety and productivity.

[0433] As shown in FIG. 30B, the negative electrode 931 is electrically connected to the terminal 951. The terminal 951 is electrically connected to the terminal 911a. Also, the positive electrode 932 is electrically connected to the terminal 952. The terminal 952 is electrically connected to the terminal 911b.

[0434] As shown in FIG. 30C, the wound body 950a and the electrolytic solution are covered by the housing 930, and the secondary battery 913 is formed. It is preferable to provide a safety valve, an overcurrent protection element, etc. in the housing 930.

[0435] As shown in FIG. 30B, the secondary battery 913 may have a plurality of wound bodies 950a. By using a plurality of wound bodies 950a, a secondary battery 913 with a larger charge / discharge capacity can be obtained. Other elements of the secondary battery 913 shown in FIGS. 30A and 30B can be referred to the description of the secondary battery 913 shown in FIG. 17.

[0436] By using the positive electrode active material described in the previous embodiment for the positive electrode 932, a secondary battery 913 with a high charge / discharge capacity and excellent cycle characteristics can be obtained.

[0437] [Secondary Battery Pack] Next, an example of the power storage device according to one aspect of the present invention will be described with reference to FIG. 21.

[0438] FIG. 21A is a diagram showing the appearance of the secondary battery pack 531. FIG. 21B is a diagram for explaining the configuration of the secondary battery pack 531. The secondary battery pack 531 includes a circuit board 501 and a secondary battery 513. A label 509 is attached to the secondary battery 513. The circuit board 501 is fixed by a seal 515. Also, the secondary battery pack 531 has an antenna 517.

[0439] The circuit board 501 has a control circuit 590. The control circuit 590 can use the battery control circuit shown in the previous embodiment. For example, as shown in FIG. 21B, the control circuit 590 is provided on the circuit board 501. Also, the circuit board 501 is electrically connected to the terminal 511. Further, the circuit board 501 is electrically connected to the antenna 517, one of the positive electrode lead and the negative electrode lead of the secondary battery 513 (551), and the other of the positive electrode lead and the negative electrode lead (552).

[0440] Alternatively, as shown in FIG. 21C, the secondary battery pack may have a circuit system 590a provided on the circuit board 501 and a circuit system 590b electrically connected to the circuit board 501 via the terminal 511. For example, a part of the control circuit according to one aspect of the present invention is provided in the circuit system 590a, and another part of the control circuit according to one aspect of the present invention is provided in the circuit system 590b.

[0441] Note that the antenna 517 is not limited to a coil shape, and may be, for example, linear or plate-shaped. Also, an antenna such as a planar antenna, an aperture antenna, a traveling wave antenna, an EH antenna, a magnetic field antenna, or a dielectric antenna may be used. Alternatively, the antenna 517 may be a flat conductor. This flat conductor can function as one of the conductors for electric field coupling. That is, the antenna 517 may be made to function as one of the two conductors of the capacitor. Thereby, power can be exchanged not only by an electromagnetic field and a magnetic field but also by an electric field.

[0442] The secondary battery pack 531 has a layer 519 between the antenna 517 and the secondary battery 513. The layer 519 has a function of, for example, shielding the electromagnetic field generated by the secondary battery 513. As the layer 519, for example, a magnetic material can be used.

[0443] The secondary battery 513 is, for example, formed by laminating a negative electrode and a positive electrode with a separator interposed therebetween and winding the laminated sheet.

[0444] This embodiment can be appropriately combined with the descriptions of other embodiments.

[0445] (Embodiment 8) In this embodiment, an example of mounting a power storage device, which is one aspect of the present invention, on a vehicle is shown. Examples of the vehicle include an automobile, a motorcycle, a bicycle, etc.

[0446] When a power storage device is mounted on a vehicle, next-generation clean energy vehicles such as a hybrid vehicle (HV), an electric vehicle (EV), or a plug-in hybrid vehicle (PHV) can be realized.

[0447] In FIG. 22, a vehicle using a power storage device, which is one aspect of the present invention, is illustrated. The automobile 8400 shown in FIG. 22A is an electric vehicle that uses an electric motor as a power source for running. Or, it is a hybrid vehicle that can appropriately select and use an electric motor and an engine as power sources for running. By using one aspect of the present invention, a vehicle with a long cruising range can be realized. The automobile 8400 has a power storage device. The power storage device can not only drive the electric motor 8406 but also supply power to a light-emitting device such as a headlight 8401 and a room light (not shown).

[0448] In addition, the power storage device can supply power to a display device such as a speedometer and a tachometer that the automobile 8400 has. Also, the power storage device can supply power to a navigation system or the like that the automobile 8400 has.

[0449] The vehicle 8500 shown in Fig. 22B can be charged by receiving power supply from an external charging facility by one or more methods such as a plug-in method and a non-contact power supply method to the power storage device 8024 of the vehicle 8500. Fig. 22B shows a state where charging is being performed from a ground-mounted charging device 8021 to the power storage device 8024 mounted on the vehicle 8500 via a cable 8022. When charging, the charging method, connector specifications, etc. may be appropriately performed in a predetermined method such as CHAdeMO (registered trademark) or Combo. The charging device 8021 may be a charging station provided in a commercial facility or may be a household power source. For example, by plug-in technology, the power storage device 8024 mounted on the vehicle 8500 can be charged by external power supply. Charging can be performed by converting AC power into DC power via a conversion device such as an AC-DC converter.

[0450] Also, although not shown, a power receiving device can be mounted on the vehicle, and power can be supplied non-contact from a power transmission device on the ground for charging. In the case of this non-contact power supply method, by incorporating a power transmission device into a road or an outer wall, charging can be performed not only while the vehicle is stopped but also while it is running. Further, using this non-contact power supply method, power may be transmitted and received between vehicles. Furthermore, a solar cell may be provided on the exterior of the vehicle to charge the power storage device when the vehicle is stopped or running. For such non-contact power supply, an electromagnetic induction method and a magnetic field resonance method can be used.

[0451] Fig. 22C is an example of a two-wheeled vehicle using a power storage device according to an aspect of the present invention. The scooter 8600 shown in Fig. 22C includes a power storage device 8602, a side mirror 8601, and a direction indicator lamp 8603. The power storage device 8602 can supply electricity to the direction indicator lamp 8603.

[0452] Also, the scooter 8600 shown in Fig. 22C can store the power storage device 8602 in the under-seat storage 8604. The power storage device 8602 can be stored in the under-seat storage 8604 even if the under-seat storage 8604 is small.

[0453] FIG. 23A shows an example of an electric bicycle using a power storage device according to an aspect of the present invention. The power storage device according to an aspect of the present invention can be applied to the electric bicycle 8700 shown in FIG. 23A. The power storage device according to an aspect of the present invention has, for example, a plurality of storage batteries, a protection circuit, and a neural network.

[0454] The electric bicycle 8700 includes a power storage device 8702. The power storage device 8702 can supply electricity to a motor that assists the driver. Further, the power storage device 8702 is portable and is shown in a state removed from the bicycle in FIG. 23B. Further, the power storage device 8702 incorporates a plurality of storage batteries 8701 included in the power storage device according to an aspect of the present invention, and can display the remaining battery level and the like on a display unit 8703. The power storage device 8702 also has a control circuit 8704 according to an aspect of the present invention. The control circuit 8704 is electrically connected to the positive and negative electrodes of the storage battery 8701. As the control circuit 8704, the battery control circuit shown in the previous embodiment can be used.

[0455] This embodiment can be appropriately combined with the descriptions of other embodiments.

[0456] (Embodiment 9) In this embodiment, an example of mounting the power storage device shown in the previous embodiment on an electronic device will be described.

[0457] Next, FIGS. 24A and 24B show an example of a two-foldable tablet terminal (including a clamshell type terminal). The tablet terminal 9600 shown in FIGS. 24A and 24B includes a housing 9630a, a housing 9630b, a movable part 9640 connecting the housing 9630a and the housing 9630b, a display unit 9631, a display mode changeover switch 9626, a power switch 9627, a power saving mode changeover switch 9625, a fastener 9629, and an operation switch 9628. By using a flexible panel for the display unit 9631, a tablet terminal having a wider display unit can be obtained. FIG. 24A shows the tablet terminal 9600 in an open state, and FIG. 24B shows the tablet terminal 9600 in a closed state.

[0458] Further, the tablet terminal 9600 has a power storage body 9635 inside the housing 9630a and the housing 9630b. The power storage body 9635 is provided across the housing 9630a and the housing 9630b through the movable part 9640.

[0459] The display unit 9631 can partly be a touch panel area, and data can be input by touching the displayed operation keys. Also, the keyboard buttons can be displayed on the display unit 9631 by touching the position where the keyboard display switching button of the touch panel is displayed with a finger or a stylus.

[0460] Also, the display mode switching switch 9626 can switch the display orientation such as vertical display or horizontal display, and can select switching between black and white display and color display. The power saving mode switching switch 9625 can optimize the display brightness according to the amount of external light detected by the optical sensor built in the tablet terminal 9600 during use. The tablet terminal may incorporate other detection devices such as sensors for detecting inclination such as a gyro and an acceleration sensor in addition to the optical sensor.

[0461] FIG. 24B shows a state where the tablet terminal is closed. The tablet terminal 9600 has a housing 9630, a solar cell 9633, and a power storage device according to an aspect of the present invention. The power storage device has a control circuit 9634 and a power storage body 9635. For the control circuit 9634, the battery control circuit shown in the previous embodiment can be used.

[0462] Note that since the tablet terminal 9600 is foldable in two, the housing 9630a and the housing 9630b can be folded so as to overlap each other when not in use. By folding, the display unit 9631 can be protected, so that the durability of the tablet terminal 9600 can be enhanced.

[0463] In addition, the tablet-type terminal shown in FIGS. 24A and 24B can also have functions such as displaying various types of information (still images, moving images, text images, etc.), displaying a calendar, date, or time on a display unit, a touch input function for touch input operations or editing of the information displayed on the display unit, a function of controlling processing by various software (programs), and the like.

[0464] Power can be supplied to a touch panel, a display unit, a video signal processing unit, or the like by a solar cell 9633 mounted on the surface of the tablet-type terminal. Note that the solar cell 9633 can be provided on one side or both sides of the housing 9630, and can be configured to efficiently charge the power storage body 9635.

[0465] In FIGS. 24A and 24B, a configuration in which a control circuit using the battery control circuit shown in the previous embodiment is applied to a two-foldable tablet-type terminal has been described, but other configurations may also be used. For example, as shown in FIG. 24C, it can also be applied to a notebook personal computer which is a clamshell-type terminal. FIG. 24C shows a notebook personal computer 9601 having a display unit 9631 in a housing 9630a and a keyboard unit 9650 in a housing 9630b. Inside the notebook personal computer 9601, there are a control circuit 9634 and a power storage body 9635 described in FIGS. 24A and 24B. For the control circuit 9634, the battery control circuit shown in the previous embodiment can be used.

[0466] FIG. 25 shows an example of another electronic device. In FIG. 25, a display device 8000 is an example of an electronic device in which a power storage device according to one aspect of the present invention is mounted. Specifically, the display device 8000 corresponds to a display device for receiving TV broadcasts, and has a housing 8001, a display unit 8002, a speaker unit 8003, a secondary battery 8004, and the like. A detection system according to one aspect of the present invention is provided inside the housing 8001. The display device 8000 can receive power supply from a commercial power source, or can use the power stored in the secondary battery 8004.

[0467] The display unit 8002 can use a light-emitting device such as a liquid crystal display device, an organic EL element, a light-emitting device having a light-emitting element such as an organic EL element in each pixel, an electrophoretic display device, a DMD (Digital Micromirror Device), a PDP (Plasma Display Panel), a FED (Field Emission Display), or the like, a semiconductor display device.

[0468] Also, the voice input device 8005 also uses a secondary battery. The voice input device 8005 has the power storage device shown in the previous embodiment. The voice input device 8005 includes, in addition to a wireless communication element, a plurality of sensors (such as an optical sensor, a temperature sensor, a humidity sensor, a barometric pressure sensor, an illuminance sensor, a motion sensor, etc.) including a microphone, and can perform power operations of other devices, such as a display device 8000, and light quantity adjustment of a lighting device 8100, according to the words commanded by the user. The voice input device 8005 can operate peripheral devices by voice and can replace a manual remote control.

[0469] Also, the voice input device 8005 has wheels or mechanical moving means, moves in the direction where the user's voice can be heard, accurately hears commands with the built-in microphone, and displays the content on the display unit 8008 or enables touch input operation of the display unit 8008.

[0470] In addition, the voice input device 8005 can also function as a charging dock for a portable information terminal 8009 such as a smartphone. The portable information terminal 8009 and the voice input device 8005 can transfer power to each other either wired or wirelessly. In the indoor environment, since there is no particular need to carry the portable information terminal 8009 around, and it is desired to ensure the necessary capacity while avoiding overloading and deterioration of the secondary battery, it is desirable that the voice input device 8005 can manage and maintain the secondary battery. Also, since the voice input device 8005 has a speaker 8007 and a microphone, hands-free conversations can be held even when the portable information terminal 8009 is being charged. Further, if the capacity of the secondary battery of the voice input device 8005 decreases, it can be moved in the direction of the arrow and charged wirelessly from a charging module 8010 connected to an external power source.

[0471] Alternatively, the voice input device 8005 may be placed on a stand. Also, the voice input device 8005 may be provided with wheels or mechanical moving means to move it to a desired position, or without providing a stand and wheels, the voice input device 8005 may be fixed at a desired position, such as on the floor.

[0472] Note that the display device includes all information display devices for TV broadcast reception, personal computers, advertisement display, etc.

[0473] In FIG. 25, the installed lighting device 8100 is an example of an electronic device using a secondary battery 8103 controlled by a microprocessor (including APS) that controls charging. Specifically, the lighting device 8100 has a housing 8101, a light source 8102, a secondary battery 8103, etc. In FIG. 25, the case where the secondary battery 8103 is provided inside the ceiling 8104 where the housing 8101 and the light source 8102 are installed is illustrated, but the secondary battery 8103 may be provided inside the housing 8101. The lighting device 8100 can receive power supply from a commercial power source or use the power stored in the secondary battery 8103.

[0474] Note that in Fig. 25, the installed lighting device 8100 provided on the ceiling 8104 is illustrated. However, the secondary battery 8103 can also be used for installed lighting devices provided on surfaces other than the ceiling 8104, such as the side wall 8105, the floor 8106, the window 8107, etc., or for desktop lighting devices and the like.

[0475] Also, as the light source 8102, an artificial light source that artificially obtains light using electricity can be used. Specifically, incandescent bulbs, discharge lamps such as fluorescent lamps, and light-emitting elements such as LEDs or organic EL elements can be cited as examples of the above artificial light sources.

[0476] In Fig. 25, an air conditioner having an indoor unit 8200 and an outdoor unit 8204 is an example of an electronic device using a secondary battery 8203. Specifically, the indoor unit 8200 includes a housing 8201, an air outlet 8202, a secondary battery 8203, etc. In Fig. 25, the case where the secondary battery 8203 is provided in the indoor unit 8200 is illustrated. However, the secondary battery 8203 may be provided in the outdoor unit 8204. Alternatively, the secondary battery 8203 may be provided in both the indoor unit 8200 and the outdoor unit 8204. The air conditioner can receive power supply from a commercial power source or use the power stored in the secondary battery 8203.

[0477] In Fig. 25, an electric refrigerator-freezer 8300 is an example of an electronic device using a secondary battery 8304. Specifically, the electric refrigerator-freezer 8300 includes a housing 8301, a refrigerator door 8302, a freezer door 8303, a secondary battery 8304, etc. In Fig. 25, the secondary battery 8304 is provided inside the housing 8301. The electric refrigerator-freezer 8300 can receive power supply from a commercial power source or use the power stored in the secondary battery 8304.

[0478] Also, during periods when the electronic device is not in use, especially during periods when the ratio of the actually used power consumption to the total power supply available from the commercial power supply source (referred to as the power utilization rate) is low, by storing power in the secondary battery, it is possible to suppress the increase in the power utilization rate outside of the above periods. For example, in the case of the electric refrigerator 8300, during the night when the temperature is low and the doors 8302 for the refrigerator compartment and 8303 for the freezer compartment are not opened or closed, power is stored in the secondary battery 8304. Then, during the day when the temperature rises and the doors 8302 for the refrigerator compartment and 8303 for the freezer compartment are opened or closed, by using the secondary battery 8304 as an auxiliary power source, the power utilization rate during the day can be kept low.

[0479] In addition to the above-described electronic devices, the secondary battery can be mounted on any electronic device. According to one aspect of the present invention, the cycle characteristics of the secondary battery are improved. Therefore, by mounting a microprocessor (including APS) for controlling charging, which is one aspect of the present invention, on the electronic device described in this embodiment, an electronic device with a longer lifespan can be obtained. This embodiment can be implemented in appropriate combination with other embodiments.

[0480] Examples of mounting the power storage device according to one aspect of the present invention on an electronic device are shown in FIGS. 26A to 26E. Examples of electronic devices to which the power storage device according to one aspect of the present invention is applied include, for example, a television device (also referred to as a TV or a television receiver), a monitor for a computer, a digital camera, a digital video camera, a digital photo frame, a mobile phone (also referred to as a cellular phone or a mobile phone device), a portable game machine, a portable information terminal, an audio reproduction device, and a large game machine such as a pachinko machine.

[0481] FIG. 26A shows an example of a mobile phone. The mobile phone 7400 includes, in addition to a display unit 7402 incorporated in a housing 7401, operation buttons 7403, an external connection port 7404, a speaker 7405, a microphone 7406, and the like. Note that the mobile phone 7400 has a power storage device according to one aspect of the present invention. The power storage device according to one aspect of the present invention has, for example, a storage battery 7407 and a battery control circuit shown in the previous embodiment.

[0482] FIG. 26B shows the state in which the mobile phone 7400 is bent. When the mobile phone 7400 is deformed by an external force and bent as a whole, the battery 7407 provided inside may also be bent. In such a case, it is preferable to use a flexible battery as the battery 7407. The bent state of the flexible battery is shown in FIG. 26C. A control circuit 7408 is electrically connected to the battery. As the control circuit 7408, the battery control circuit shown in the previous embodiment can be used.

[0483] In addition, it is also possible to incorporate a battery having a flexible shape along the inner and outer walls of houses and buildings and the curved surfaces of the interior or exterior of automobiles.

[0484] FIG. 26D shows an example of a bangle-type display device. The portable display device 7100 has a housing 7101, a display unit 7102, operation buttons 7103, and a power storage device according to an aspect of the present invention. The power storage device according to an aspect of the present invention has, for example, a battery 7104 and the battery control circuit shown in the previous embodiment.

[0485] FIG. 26E shows an example of a wristwatch-type portable information terminal. The portable information terminal 7200 includes a housing 7201, a display unit 7202, a band 7203, a buckle 7204, operation buttons 7205, input / output terminals 7206, and the like.

[0486] The portable information terminal 7200 can execute various applications such as mobile phones, e-mails, text viewing and creation, music playback, Internet communication, and computer games.

[0487] The display surface of the display unit 7202 is provided to be curved, and the display can be performed along the curved display surface. In addition, the display unit 7202 includes a touch sensor and can be operated by touching the screen with a finger or a stylus. For example, an application can be launched by touching the icon 7207 displayed on the display unit 7202.

[0488] In addition to time setting, the operation button 7205 can be provided with various functions such as turning on and off the power supply, turning on and off wireless communication, executing and canceling the manner mode, and executing and canceling the power saving mode. For example, the function of the operation button 7205 can also be freely set by the operating system incorporated in the portable information terminal 7200.

[0489] In addition, the portable information terminal 7200 can execute short-range wireless communication that complies with a communication standard. For example, it is also possible to make a hands-free call by communicating with a wireless communication-enabled headset.

[0490] In addition, the portable information terminal 7200 is provided with an input / output terminal 7206 and can directly exchange data with other information terminals via a connector. Charging can also be performed via the input / output terminal 7206. Note that the charging operation may be performed by wireless power supply without using the input / output terminal 7206.

[0491] The portable information terminal 7200 has a power storage device according to one aspect of the present invention. The power storage device includes a storage battery and a battery control circuit shown in the previous embodiment.

[0492] The portable information terminal 7200 preferably has a sensor. As the sensor, for example, one or more selected from human body sensors such as a fingerprint sensor, a pulse sensor, and a body temperature sensor, and a touch sensor, a pressure sensor, an acceleration sensor, etc. are preferably mounted.

[0493] This embodiment can be appropriately combined with the descriptions of other embodiments.

[0494] (Embodiment 10) This embodiment will describe an example of a system equipped with a battery control circuit according to one aspect of the present invention.

[0495] FIG. 27A is a conceptual diagram of a battery control system in which a semiconductor device 810 formed on a flexible substrate 811, which is a flexible film, is mounted on a cylindrical secondary battery 815.

[0496] As the semiconductor device 810, for example, the semiconductor device 900 shown in the previous embodiment can be applied. Alternatively, as the semiconductor device 810, for example, some components of the semiconductor device 900 shown in the previous embodiment, such as the components provided in the layer 585, may be applied.

[0497] A battery control system according to an aspect of the present invention includes at least a cylindrical secondary battery 815, a semiconductor device 810, and a switch.

[0498] The cylindrical secondary battery 815 has a first terminal 812 on the upper surface and a second terminal 813 on the bottom surface. A first transmission path connected to the first terminal 812 of the cylindrical secondary battery and transmitting the power output from the cylindrical secondary battery 815 is electrically connected to the terminal of the charge control circuit via the electrode 818. Also, a second transmission path connected to the second terminal 813 of the cylindrical secondary battery is connected to a switch that cuts off the second transmission path via the electrode 819.

[0499] In FIG. 27A, two switches (also referred to as cut-off switches) for cutting off the second transmission path are provided, and diodes are also connected respectively, functioning as a protection circuit for preventing over-discharge, over-charge, or over-current. The switch controls the conduction and cut-off operations and can also be called a switching means for switching between supply and cut-off. A third terminal 814, which is the other terminal of the second transmission path formed on the flexible substrate 811, is connected to one or more of the charger 816 and the mobile device 817.

[0500] A manufacturing method for forming a semiconductor device 810 on a flexible substrate 811 uses a method of fixing it on the flexible substrate 811 after peeling using a peeling method after forming it on a semiconductor substrate. In the peeling method, known techniques can be used. Also, after forming on a semiconductor substrate, it may be fixed on the flexible substrate 811 after polishing the back surface. Also, a method of fixing it on the flexible substrate 811 after a so-called laser cut, in which it is partially cut using a laser beam, may be used. Also, a method of directly forming the semiconductor device 810 on the flexible substrate 811 may be used. Also, a method of fixing the semiconductor device 810 formed on a glass substrate on the flexible substrate 811 after peeling using a peeling method is used.

[0501] In this embodiment, although examples of forming or mounting these diodes and switches on the flexible substrate 811 are shown, it is not particularly limited to this configuration.

[0502] When an abnormality such as a micro short is detected in the semiconductor device 810, the second transmission path can be blocked by inputting a signal to the gate of the switch that blocks the second transmission path. By blocking the second transmission path, the supply of current from the charger 816 or the supply of current to the mobile device 817 can be stopped. Also, by holding the signal voltage applied to the gate of the switch that blocks the second transmission path in a memory circuit (including a transistor using an oxide semiconductor), the block can be maintained for a long time. Therefore, a highly safe charging control system can be achieved.

[0503] Also, FIG. 27B is a process diagram showing a state immediately before bonding the cylindrical secondary battery 815 and the flexible substrate 811, and shows the contact surface side of the flexible substrate 811. As shown in FIG. 27B, the body portion of the cylindrical secondary battery 815 is applied to the contact surface of the flexible substrate 811 and rolled, and the flexible substrate 811 is wound and adhered in the circumferential direction of the body portion. Also, although the electrodes 818 and 819 are arranged side by side in the Y direction on the flexible substrate 811, it is not particularly limited, and one may be shifted in the X direction. Note that the figure after rolling is FIG. 27C.

[0504] An exterior film is attached so as to cover the outer peripheral surface of the cylindrical secondary battery 815. This exterior film protects a metal can for sealing the internal structure of the secondary battery and is used to insulate from the metal can.

[0505] When the outer surface (excluding the terminal portion) of the cylindrical secondary battery 815 is a metal surface without using an exterior film, it is preferable to sandwich an insulating sheet between the electrode 818 and between the electrode 819. The electrode 818 or the electrode 819 is a conductive metal foil, a conductive tape made of a conductive material, or a lead wire, and is connected to the terminal of the cylindrical secondary battery 815 by a known method such as soldering or wire bonding. Also, the electrode 818 or the electrode 819 is connected to the terminal of the charge control circuit by soldering or wire bonding.

[0506] As shown in FIG. 27A, when power is supplied from the cylindrical secondary battery 815 to the mobile device 817, the cylindrical secondary battery 815 is in a discharged state, and the behavior such as voltage and current at the first terminal 812 and the second terminal 813 is monitored by the semiconductor device 810. When an abnormality is detected, the second transmission path is cut off to stop the discharge.

[0507] The mobile device 817 refers to a configuration other than the secondary battery, and the power source for the mobile device 817 is the cylindrical secondary battery 815. Note that the mobile device 817 is an electronic device that can be carried around.

[0508] Also, when the cylindrical secondary battery 815 is charged by supplying power from the charger 816, the cylindrical secondary battery 815 is in a charged state, and the behavior such as voltage and current at the first terminal 812 and the second terminal 813 is monitored by the semiconductor device 810. When an abnormality is detected, the second transmission path is cut off to stop the charging.

[0509] The charger 816 refers to a device having an adapter connected to an external power source or a device that performs power transmission using a wireless signal. Note that the charger 816 may be built into the mobile device 817.

[0510] In FIG. 27A, an example of a cylindrical secondary battery was shown. As a different example, FIG. 28A shows an example in which a semiconductor device 964 formed on a flexible substrate 910, which is a flexible film, is mounted on a flat secondary battery 963.

[0511] The semiconductor device 964 is formed or fixed on the flexible substrate 910. The semiconductor device 964 detects abnormalities such as micro-shorts. Further, it may have a function as a protection circuit that protects the secondary battery 963 from overcharging, over-discharging, and over-current.

[0512] As the semiconductor device 964, for example, the semiconductor device 900 shown in the previous embodiment can be applied. Alternatively, as the semiconductor device 810, for example, a partial configuration of the semiconductor device 900 shown in the previous embodiment, for example, a configuration provided in the layer 585, may be applied.

[0513] In addition to the semiconductor device 964, an antenna, a receiving circuit, and a rectifying circuit may be provided. Charging can also be performed non-contact with the secondary battery 963 using the antenna. The antenna is not limited to a coil shape and may be, for example, linear or plate-shaped. Also, an antenna such as a planar antenna, an aperture antenna, a traveling wave antenna, an EH antenna, a magnetic field antenna, a dielectric antenna, etc. may be used. The antenna has a function that can perform data communication with an external device, for example. As a communication method between the battery pack and other devices via the antenna, a response method that can be used between the battery pack and other devices, such as NFC, can be applied.

[0514] As shown in FIG. 28B, the connection terminal 911 is electrically connected to the terminals 951 and 952 of the secondary battery 963 via the semiconductor device 964. Note that a plurality of connection terminals 911 may be provided, and each of the plurality of connection terminals 911 may be used as a control signal input terminal, a power supply terminal, etc.

[0515] The battery pack has an insulating sheet layer 916 between the semiconductor device 964 and the secondary battery 963. The insulating sheet layer 916 has a function of, for example, preventing a short circuit caused by the secondary battery 963. As the insulating sheet layer 916, for example, an organic resin film or an adhesive sheet can be used.

[0516] In FIG. 28A, an example is shown in which the insulating sheet layer 916 is provided on the surface of the housing, and the flexible substrate is fixed with the surface on which the semiconductor device 964 is provided facing inward, but it is not particularly limited. The surface on which the charge control circuit is formed may face outward and be connected to the terminal 951 or the terminal 952. However, in that case, the connection portion will be exposed, and there is a risk of electrostatic breakdown or short circuit, so care must be taken during assembly.

[0517] In the above, an example in which the semiconductor device 964 is provided on the flexible substrate is shown, but it is not particularly limited. A protection circuit, a cutoff switch, an antenna, a sensor, etc. may be provided on the same substrate. The semiconductor device 964 is formed on the flexible substrate, can be bent, and can detect abnormalities such as a micro short circuit of the secondary battery. Further, the semiconductor device according to one aspect of the present invention can be provided on the side surface of the secondary battery, and space saving and reduction in the number of parts used can be achieved.

[0518] An example of an electronic device equipped with a battery control circuit according to one aspect of the present invention will be described with reference to FIG. 29.

[0519] The cleaning robot 7000 has a secondary battery, a display arranged on the upper surface, a plurality of cameras arranged on the side surface, a brush, operation buttons, various sensors, etc. Although not shown, the cleaning robot 7000 is provided with tires, a suction port, etc. The cleaning robot 7000 can move autonomously, detect dust, and suck dust from the suction port provided on the lower surface. By applying a semiconductor device equipped with a battery control circuit according to one aspect of the present invention that is electrically connected to the secondary battery of the cleaning robot 7000, the number of parts used can be reduced, and abnormalities such as a micro short circuit of the secondary battery can be detected.

[0520] The cleaning robot 7000 is equipped with a secondary battery, an illuminance sensor, a microphone, a camera, a speaker, various sensors (such as an infrared sensor, an ultrasonic sensor, an acceleration sensor, a piezo sensor, a light sensor, a gyro sensor, etc.), and a moving mechanism. By applying a semiconductor device equipped with the battery control circuit of one aspect of the present invention to the secondary battery of the cleaning robot 7000, control and protection of the secondary battery can be performed.

[0521] The microphone has a function of detecting acoustic signals such as the user's voice and environmental sound. Also, the speaker has a function of emitting audio signals such as voice and warning sounds. The cleaning robot 7000 can analyze the audio signal input through the microphone and emit the necessary audio signal from the speaker. In the cleaning robot 7000, communication with the user is possible using the microphone and the speaker.

[0522] The camera has a function of imaging the surroundings of the cleaning robot 7000. Also, the cleaning robot 7000 has a function of moving using the moving mechanism. The cleaning robot 7000 can use the camera to image the surrounding images and analyze the images to detect the presence or absence of obstacles when moving.

[0523] The flying object 7120 has a propeller, a camera, a secondary battery, etc., and has a function of flying autonomously.

[0524] Also, by applying a semiconductor device equipped with the battery control circuit of one aspect of the present invention to the secondary battery of the flying object 7120, in addition to weight reduction, control and protection of the secondary battery can be performed.

[0525] An example of a moving object is shown as an electric vehicle 7160. The electric vehicle 7160 has a secondary battery, tires, brakes, a steering device, a camera, etc. By applying a semiconductor device equipped with the battery control circuit of one aspect of the present invention connected to the secondary battery of the electric vehicle 7160, the number of parts used can be reduced, and abnormalities such as a micro short circuit of the secondary battery can be detected.

[0526] In the above description, an electric vehicle is described as an example of a moving body. However, the moving body is not limited to an electric vehicle. For example, examples of the moving body include trains, monorails, ships, flying bodies (helicopters, unmanned aerial vehicles (drones), airplanes, rockets), etc. A semiconductor device equipped with a battery control circuit according to one aspect of the present invention that is electrically connected to a secondary battery of these moving bodies can be applied to reduce the number of parts used and detect abnormalities such as micro-shorts in the secondary battery.

[0527] The cylindrical secondary battery equipped with the semiconductor device 810 and / or the battery pack equipped with the semiconductor device 964 can be incorporated into a smartphone 7210, a PC 7220 (personal computer), a game machine 7240, etc. Note that the semiconductor device 810 attached to the cylindrical secondary battery corresponds to the semiconductor device 810 shown in FIG. 27. Also, the semiconductor device 964 attached to the battery pack corresponds to the semiconductor device 964 shown in FIG. 28.

[0528] The smartphone 7210 is an example of a mobile information terminal. The smartphone 7210 has a microphone, a camera, a speaker, various sensors, and a display unit. These peripheral devices are controlled by a semiconductor device equipped with a battery control circuit. By applying a semiconductor device equipped with a battery control circuit according to one aspect of the present invention that is electrically connected to the secondary battery of the smartphone 7210, the number of parts used can be reduced, and the control and protection of the secondary battery, etc. can be performed, and the safety can be enhanced.

[0529] The PC 7220 is an example of a notebook PC. By applying a semiconductor device equipped with a battery control circuit according to one aspect of the present invention that is electrically connected to the secondary battery of the notebook PC, the number of parts used can be reduced, and the control and protection of the secondary battery, etc. can be performed, and the safety can be enhanced.

[0530] The game machine 7240 is an example of a portable game machine. The game machine 7260 is an example of a home console game machine. A controller 7262 is connected to the game machine 7260 either wirelessly or by wire. By applying a semiconductor device equipped with a battery control circuit according to one aspect of the present invention to the controller 7262, the number of parts used can be reduced, and the control and protection of the secondary battery can be performed, thereby enhancing safety.

[0531] This embodiment can be implemented in appropriate combination with the configurations described in other embodiments and the like.

[0532] (Embodiment 11) In this embodiment, an example of mounting a secondary battery, which is one aspect of the present invention, on an electronic device or a moving body will be described.

[0533] First, examples of mounting a secondary battery on an electronic device, which were described in the previous embodiment, are shown in FIGS. 31A to 31D. Examples of electronic devices to which a bendable secondary battery is applied include, for example, a television device (also referred to as a TV or a television receiver), a monitor for a computer, a digital camera, a digital video camera, a digital photo frame, a mobile phone (also referred to as a cellular phone or a mobile phone device), a portable game machine, a portable information terminal, an audio playback device, and a large game machine such as a pachinko machine.

[0534] In addition, a secondary battery can be applied to a moving body, typically an automobile. Examples of automobiles include next-generation clean energy vehicles such as hybrid vehicles (HV), electric vehicles (EV), or plug-in hybrid vehicles (PHV), and a secondary battery can be applied as one of the power sources mounted on the automobile. The moving body is not limited to an automobile. For example, examples of the moving body include a train, a monorail, a ship, an aircraft (helicopter, unmanned aerial vehicle (drone), airplane, rocket), an electric bicycle, and an electric motorcycle, and a secondary battery according to one aspect of the present invention can be applied to these moving bodies.

[0535] Further, the secondary battery of the present embodiment may be applied to a ground-mounted charging device provided in a house or a charging station provided in a commercial facility.

[0536] FIG. 31A shows an example of a mobile phone. The mobile phone 2100 includes, in addition to a display unit 2102 incorporated in a housing 2101, operation buttons 2103, an external connection port 2104, a speaker 2105, a microphone 2106, and the like. Note that the mobile phone 2100 has a secondary battery 2107.

[0537] The mobile phone 2100 can execute various applications such as mobile phone calls, e-mails, text viewing and creation, music playback, Internet communication, and computer games.

[0538] In addition to time setting, the operation buttons 2103 can have various functions such as power on / off operations, wireless communication on / off operations, execution and cancellation of a manner mode, and execution and cancellation of a power saving mode. For example, the functions of the operation buttons 2103 can be freely set by an operating system incorporated in the mobile phone 2100.

[0539] Further, the mobile phone 2100 can execute communication-standardized short-range wireless communication. For example, it can communicate with a wireless headset to make a hands-free call.

[0540] The mobile phone 2100 includes an external connection port 2104 and can directly exchange data with other information terminals via a connector. Charging can also be performed via the external connection port 2104. Note that the charging operation may be performed by wireless power supply without using the external connection port 2104.

[0541] The mobile phone 2100 preferably has a sensor. As the sensor, for example, a human body sensor such as a fingerprint sensor, a pulse sensor, or a body temperature sensor, or a touch sensor, a pressure sensor, an acceleration sensor, or the like is preferably mounted.

[0542] Figure 31B shows an unmanned aerial vehicle 2300 having a plurality of rotors 2302. The unmanned aerial vehicle 2300 may also be called a drone. The unmanned aerial vehicle 2300 includes a secondary battery 2301, a camera 2303, and an antenna (not shown) according to one aspect of the present invention. The unmanned aerial vehicle 2300 can be remotely controlled via the antenna. Since the secondary battery according to one aspect of the present invention is highly safe, it can be safely used for a long time over a long period, and is suitable as a secondary battery mounted on the unmanned aerial vehicle 2300.

[0543] Also, as shown in Figure 31C, a secondary battery 2602 having a plurality of secondary batteries 2601 according to one aspect of the present invention may be mounted on a hybrid vehicle (HV), an electric vehicle (EV), a plug-in hybrid vehicle (PHV), or other electronic devices.

[0544] Figure 31D shows an example of a vehicle equipped with the secondary battery 2602. The vehicle 2603 is an electric vehicle that uses an electric motor as a power source for running. Alternatively, it is a hybrid vehicle that can appropriately select and use an electric motor and an engine as a power source for running. The vehicle 2603 using an electric motor has a plurality of ECUs (Electronic Control Units), and the ECU performs engine control and the like. The ECU includes a microcomputer. The ECU is connected to a CAN (Controller Area Network) provided in the electric vehicle. The CAN is one of the serial communication standards used as an in-vehicle LAN. By using the secondary battery according to one aspect of the present invention, it can function as a power source for the ECU, and a vehicle with high safety and a long cruising range can be realized.

[0545] The secondary battery can not only drive an electric motor (not shown), but also supply power to a light-emitting device such as a headlight and a room light. In addition, the secondary battery can supply power to a display device and a semiconductor device such as a speedometer, a tachometer, and a navigation system of the vehicle 2603.

[0546] The vehicle 2603 can be charged by receiving power supply from an external charging facility by one or more methods such as a plug-in method and a non-contact power supply method for the secondary battery included in the secondary battery 2602.

[0547] Next, an example of a power storage device according to one aspect of the present invention will be described with reference to FIGS. 32A and 32B.

[0548] The house shown in FIG. 32A has a power storage device 2612 having a secondary battery which is one aspect of the present invention, and a solar panel 2610. The power storage device 2612 is electrically connected via the solar panel 2610, wiring 2611, etc. Further, the power storage device 2612 and a ground-mounted charging device 2604 may be electrically connected. The power obtained by the solar panel 2610 can be used to charge the power storage device 2612. Also, the power stored in the power storage device 2612 can be used to charge the secondary battery 2602 included in the vehicle 2603 via the charging device 2604. The power storage device 2612 is preferably installed in the underfloor space. By installing it in the underfloor space, the space on the floor can be effectively utilized. Alternatively, the power storage device 2612 may be installed on the floor.

[0549] The power stored in the power storage device 2612 can also be supplied to other electronic devices in the house. Therefore, even when power supply from the commercial power supply cannot be received due to a power outage or the like, by using the power storage device 2612 according to one aspect of the present invention as an uninterruptible power supply, the electronic devices can be used.

[0550] FIG. 32A shows a state in which a vehicle 2603 is being charged from a ground-mounted charging device 2604 via a cable. When charging, the charging method, connector specifications, etc. may be appropriately carried out in a predetermined manner such as CHAdeMO (registered trademark) or Combo. For example, by means of a plug-in technique, the secondary battery 2602 mounted on the vehicle 2603 can be charged by external power supply. Charging can be performed by converting AC power into DC power via a conversion device such as an AC-DC converter. The charging device 2604 may be provided in a house as shown in FIG. 32A, or may be a charging station provided in a commercial facility.

[0551] Also, although not shown, a power receiving device can be mounted on the vehicle, and power can be supplied non-contact from a power transmission device on the ground for charging. In the case of this non-contact power supply method, by incorporating a power transmission device into a road or an outer wall, charging can be performed not only while the vehicle is parked but also while it is running. Also, using this non-contact power supply method, power can be transmitted and received between vehicles. Furthermore, a solar cell can be provided on the exterior of the vehicle to charge the secondary battery when parked or running. For such non-contact power supply, one or more of an electromagnetic induction method and a magnetic field resonance method can be used.

[0552] FIG. 32B shows an example of a power storage device 700 according to an aspect of the present invention. As shown in FIG. 32B, a power storage device 791 according to an aspect of the present invention is installed in the underfloor space 796 of a building 799.

[0553] A control device 790 is installed in the power storage device 791, and the control device 790 is electrically connected to a distribution board 703, a power storage controller 705 (also referred to as a control device), a display 706, and a router 709 by wiring.

[0554] Electric power is sent from the commercial power supply 701 to the distribution board 703 via the lead wire attachment part 710. Also, electric power is sent to the distribution board 703 from the power storage device 791 and the commercial power supply 701, and the distribution board 703 supplies the received electric power to the general load 707 and the power storage system load 708 via an outlet (not shown).

[0555] The general load 707 is an electronic device such as a TV or a personal computer, for example, and the power storage system load 708 is an electronic device such as a microwave oven, a refrigerator, or an air conditioner, for example.

[0556] The power storage controller 705 includes a measurement unit 711, a prediction unit 712, and a planning unit 713. The measurement unit 711 has a function of measuring the amount of electric power consumed by the general load 707 and the power storage system load 708 during one day (for example, from 0:00 to 24:00). Also, the measurement unit 711 may have a function of measuring the amount of electric power of the power storage device 791 and the amount of electric power supplied from the commercial power supply 701. Further, the prediction unit 712 has a function of predicting the amount of required electric power to be consumed by the general load 707 and the power storage system load 708 during the next day based on the amount of electric power consumed by the general load 707 and the power storage system load 708 during one day. Also, the planning unit 713 has a function of making a charge / discharge plan for the power storage device 791 based on the amount of required electric power predicted by the prediction unit 712.

[0557] The amount of electric power consumed by the general load 707 and the power storage system load 708 measured by the measurement unit 711 can be confirmed by the display 706. Also, it can be confirmed on electronic devices such as a TV and a personal computer via the router 709. Furthermore, it can also be confirmed by portable electronic terminals such as a smartphone and a tablet via the router 709. Also, the amount of required electric power for each time period (or for each hour) predicted by the prediction unit 712 can also be confirmed by the display 706, the electronic devices, and the portable electronic terminals.

[0558] This embodiment can be used in appropriate combination with other embodiments.

[0559] (Supplementary Note Regarding the Descriptions in this Specification, etc.) Regarding the above embodiments and the descriptions of each configuration in the embodiments, the following supplementary notes are provided.

[0560] The configurations shown in each embodiment can be appropriately combined with the configurations shown in other embodiments to form an aspect of the present invention. Also, when multiple configuration examples are shown in one embodiment, it is possible to appropriately combine the configuration examples.

[0561] Note that the content described in a certain embodiment (even a part of the content) can be applied, combined, or replaced with the content described in another part of the same embodiment (even a part of the content) and / or the content described in one or more other embodiments (even a part of the content).

[0562] Note that the content described in the embodiments refers to the content described using various figures in each embodiment or the content described using the text written in the specification.

[0563] Note that the figure (even a part of it) described in a certain embodiment can be combined with another part of the figure, another figure (even a part of it) described in the same embodiment, and / or the figure (even a part of it) described in one or more other embodiments to form more figures.

[0564] Also, in this specification, etc., in the block diagram, components are classified by function and shown as independent blocks. However, in an actual circuit, etc., it is difficult to separate components by function, and there may be cases where a single circuit is related to multiple functions or a single function is related to multiple circuits. Therefore, the blocks in the block diagram are not limited to the components described in the specification and can be appropriately rephrased according to the situation.

[0565] In the drawings, the size, layer thickness, or area are shown in arbitrary sizes for convenience of explanation. Therefore, they are not necessarily limited to that scale. Note that the drawings are schematically shown for clarity and are not limited to the shapes or values shown in the drawings. For example, it is possible to include variations in signals, voltages, or currents due to noise, or variations in signals, voltages, or currents due to timing shifts.

[0566] In this specification and the like, when explaining the connection relationship of a transistor, the notations "one of the source or drain" (or the first electrode, or the first terminal) and the other of the source and drain are referred to as "the other of the source or drain" (or the second electrode, or the second terminal). This is because the source and drain of a transistor change depending on the structure or operating conditions of the transistor. Note that the names of the source and drain of a transistor can be appropriately rephrased according to the situation, such as the source (drain) terminal or the source (drain) electrode.

[0567] Also, in this specification and the like, the terms "electrode" and "wiring" do not functionally limit these components. For example, an "electrode" may be used as part of a "wiring", and vice versa. Furthermore, the terms "electrode" and "wiring" also include cases where a plurality of "electrodes" and "wirings" are integrally formed.

[0568] Also, in this specification and the like, voltage and potential can be appropriately rephrased. Voltage is the potential difference from a reference potential. For example, if the reference potential is the ground voltage, the voltage can be rephrased as a potential. The ground potential does not necessarily mean 0V. Note that potential is relative, and depending on the reference potential, the potential applied to a wiring or the like may be changed.

[0569] In this specification and the like, terms such as "film" and "layer" can be interchanged with each other in some cases or depending on the situation. For example, the term "conductive layer" may be changed to the term "conductive film" in some cases. Or, for example, the term "insulating film" may be changed to the term "insulating layer" in some cases.

[0570] In this specification and the like, a switch refers to something that can be in a conductive state (on state) or a non-conductive state (off state) and has a function of controlling whether to allow current to flow or not. Or, a switch refers to something that has a function of selecting and switching the path through which current flows.

[0571] In this specification and the like, the channel length refers to, for example, in the top view of a transistor, the distance between the source and the drain in the region where the semiconductor (or the part where current flows in the semiconductor when the transistor is in the on state) and the gate overlap, or in the region where the channel is formed.

[0572] In this specification and the like, the channel width refers to, for example, in the region where the semiconductor (or the part where current flows in the semiconductor when the transistor is in the on state) and the gate electrode overlap, or in the region where the channel is formed, the length of the portion where the source and the drain face each other.

[0573] In this specification and the like, when it is stated that A and B are connected, it shall include not only the case where A and B are directly connected but also the case where they are electrically connected. Here, when A and B are electrically connected, it means that when there is an object having some electrical action between A and B, it enables the transfer of electrical signals between A and B.

Explanation of Reference Numerals

[0574] C11: Capacitance element, CND: Counter circuit, CM1_IN: Input terminal, CM1_OUT: Output terminal, CP1_IN: Input terminal, CP1_OUT: Output terminal, IF: Interface circuit, LTC: Latch circuit, MSD: Detection circuit, N1: Node, N2: Node, N6: Node, N11: Node, N12: Node, N13: Node, OUT11: Output terminal, OUT12: Output terminal, OUT31: Output terminal, OUT32: Output terminal, OUT41: Output terminal, OUT51: Output terminal, OUT52: Output terminal, OUT53: Output terminal, SD: Detection circuit, SENS: Terminal, SH1: Terminal, SH2: Terminal, SH3: Terminal, SH4: Terminal, SH6: Terminal, SH_IN: Wiring, S_OUT: Output terminal, T1: Control signal, T2: Control signal, VB_2: Wiring, VB1: Potential, VB1_IN: Wiring, VB2: Potential, VB2_IN: Wiring, VB3: Potential, VB3_IN: Wiring, VBM: Negative electrode potential, VBM_IN: Wiring, VBP: Positive electrode potential, VBP_IN: Wiring, VC1: Terminal, VC2: Terminal, VCN: Terminal, VDD: High power supply potential, VM: Terminal, VT: Terminal, Vt: Input terminal, VSS: Low power supply potential, VSSS: Terminal, 11: Transistor, 12: Transistor, 13: Transistor, 14: Transistor, 15: Transistor, 21: Transistor, 22: Transistor, 23: Transistor, 24: Transistor, 25: Transistor, 50: Comparator, 100: Energy storage device, 101: Battery control circuit, 101a: Circuit, 101b: Circuit, 113: Comparator, 114: Memory element, 119: Voltage generation circuit, 120: Battery pack, 121: Battery cell, 130: Cell balancing circuit, 130a: Cell balancing circuit, 131: Resistance element, 132: Transistor, 140: Transistor, 150: Transistor, 161: Capacitance element, 162: Transistor, 172: Transistor, 182: Logic circuit, 185: Detection circuit, 185a: Detection circuit, 185c: Circuit, 185d: Circuit, 186: Detection circuit, 245: Insulating layer, 300: Transistor, 311: Substrate, 311b: Substrate, 313: Semiconductor region, 314a: Low resistance region, 314b: Low resistance region, 315: Insulator, 316: Conductor, 317: Low resistance region, 318: Back electrode, 319: Region, 320: Insulator, 321: Insulator, 322: Insulator, 322b: Insulator, 324: Insulator, 326: Insulator, 328: Conductor,328b: Conductor, 328c: Conductor, 330: Conductor, 350: Insulator, 352: Insulator, 354: Insulator, 356: Conductor, 385: Layer, 400: Secondary battery, 401: Positive electrode cap, 402: Battery can, 410: Gasket, 413: Conductive plate, 414: Conductive plate, 415: Power storage device, 416: Wiring, 420: Control circuit, 421: Wiring, 422: Wiring, 423: Wiring, 424: Conductor, 425: Insulator, 426: Wiring, 500: Transistor, 501: Circuit board, 503: Conductor, 503a: Conductor, 503b: Conductor, 509: Label, 510: Insulator, 511: Terminal, 512: Insulator, 513: Secondary battery, 514: Insulator, 515: Seal, 516: Insulator, 517: Antenna, 518: Conductor, 519: Layer, 520: Insulator, 522: Insulator, 524: Insulator, 530: Oxide, 530a: Oxide, 530b: Oxide, 530c: Oxide, 531: Secondary battery pack, 540a: Conductor, 540b: Conductor, 542a: Conductor, 542b: Conductor, 543a: Region, 543b: Region, 544: Insulator, 546: Conductor, 546b: Conductor, 548: Conductor, 548b: Conductor, 550: Insulator, 551: One side, 552: The other side, 560: Conductor, 560a: Conductor, 560b: Conductor, 574: Insulator, 580: Insulator, 581: Insulator, 582: Insulator, 585: Layer, 590: Control circuit, 590a: Circuit system, 590b: Circuit system, 600: Capacitive element, 603: Positive electrode terminal, 604: Positive electrode, 605: Separator, 606: Negative electrode, 607: Negative electrode terminal, 608: Insulating plate, 609: Insulating plate, 610a: Conductor, 610b: Conductor, 611: PTC element, 613: Safety valve mechanism, 620: Conductor, 630: Insulator, 631: Conductor, 632: Conductor, 637: Bump, 638: Printed circuit board, 639: Resin layer, 640: Insulator, 641: Resin layer, 642: Wire, 700: Power storage device, 701: Commercial power supply, 703: Distribution board, 705: Power storage controller, 706: Display, 707: General load, 708: Power storage system load, 709: Router, 710: Lead wire attachment part, 711: Measuring part, 712: Prediction part, 713: Planning part, 790: Control device, 791: Power storage device, 796: Underfloor space part, 799: Building, 810: Semiconductor device, 811: Flexible substrate, 812: Terminal, 813: Terminal, 814: Terminal, 815: Cylindrical secondary battery, 816: Charger,817: Mobile device, 818: Electrode, 819: Electrode, 900: Semiconductor device, 901: Insulator, 902: Insulator, 903: Conductor, 903b: Conductor, 910: Flexible substrate, 911: Connection terminal, 911a: Terminal, 911b: Terminal, 913: Secondary battery, 914: Antenna, 916: Insulating sheet layer, 930: Housing, 931: Negative electrode, 931a: Negative electrode active material layer, 932: Positive electrode, 932a: Positive electrode active material layer, 933: Separator, 950a: Wound body, 951: Terminal, 952: Terminal, 963: Secondary battery, 964: Semiconductor device, 1201: Circuit, 1202: Bump, 1203: Printed circuit board, 1204: Chip, 1221: DRAM, 1222: Flash memory, 1223: Integrated circuit, 1225: Circuit, 2100: Mobile phone, 2101: Housing, 2102: Display unit, 2103: Operation button, 2104: External connection port, 2105: Speaker, 2106: Microphone, 2107: Secondary battery, 2300: Unmanned aerial vehicle, 2301: Secondary battery, 2302: Rotor, 2303: Camera, 2601: Secondary battery, 2602: Secondary battery, 2603: Vehicle, 2604: Charging device, 2610: Solar panel, 2611: Wiring, 2612: Power storage device, 7000: Cleaning robot, 7100: Portable display device, 7101: Housing, 7102: Display unit, 7103: Operation button, 7104: Rechargeable battery, 7120: Flying object, 7160: Electric vehicle, 7200: Portable information terminal, 7201: Housing, 7202: Display unit, 7203: Band, 7204: Buckle, 7205: Operation button, 7206: Input / output terminal, 7207: Icon, 7210: Smartphone, 7220: PC, 7240: Game console, 7260: Game console, 7262: Controller, 7400: Mobile phone, 7401: Housing, 7402: Display unit, 7403: Operation button, 7404: External connection port, 7405: Speaker, 7406: Microphone, 7407: Rechargeable battery, 7408: Control circuit, 8000: Display device, 8001: Housing, 8002: Display unit, 8003: Speaker section, 8004: Secondary battery, 8005: Voice input device, 8007: Speaker, 8008: Display unit, 8009: Portable information terminal, 8010: Charging module, 8021: Charging device, 8022: Cable, 8024: Power storage device, 8100: Lighting device, 8101: Housing, 8102: Light source, 8103: Secondary battery, 8104: Ceiling, 8105: Side wall, 8106: Floor,8107: Window, 8200: Indoor unit, 8201: Housing, 8202: Air outlet, 8203: Secondary battery, 8204: Outdoor unit, 8300: Electric refrigerator-freezer, 8301: Housing, 8302: Refrigerator door, 8303: Freezer door, 8304: Secondary battery, 8400: Automobile, 8401: Headlight, 8406: Electric motor, 8500: Automobile, 8600: Scooter, 8601: Side mirror, 8602: Power storage device, 8603: Direction indicator, 8604: Under-seat storage, 8700: Electric bicycle, 8701: Storage battery, 8702: Power storage device, 8703: Display unit, 8704: Control circuit, 9600: Tablet terminal, 9601: Notebook personal computer, 9625: Switch, 9626: Switch, 9627: Power switch, 9628: Operation switch, 9629: Fastener, 9630: Housing, 9630a: Housing, 9630b: Housing, 9631: Display unit, 9633: Solar cell, 9634: Control circuit, 9635: Power storage body, 9640: Movable part, 9650: Keyboard section,

Claims

1. 1. A semiconductor device comprising: a first transistor; a first insulator on the first transistor; a second transistor located above the first insulator; and a second insulator having a region located above the second transistor, a first conductor embedded in the first insulator; a second conductor and a third conductor embedded in the second insulator; a fourth conductor above the second insulator; the second transistor has a region overlapping with the first transistor in a cross-sectional view; In a cross-sectional view, the first conductor has an area overlapping the second conductor and does not overlap the third conductor; the fourth conductor has a region overlapping with the second transistor in a cross-sectional view; the first conductor is electrically connected to one of a source electrode or a drain electrode of the first transistor, and is also electrically connected to the second conductor; The third conductor is electrically connected to the second transistor, and is also electrically connected to the second conductor via the fourth conductor.

2. The semiconductor device according to claim 1 , wherein the fourth conductor has a region overlapping with the first transistor in a cross-sectional view.

3. a fifth conductor electrically connected to the fourth conductor; the fifth conductor has an area overlapping with the second conductor in a cross-sectional view, 3. The semiconductor device according to claim 1, wherein the fifth conductor is electrically connected to a bump or a wire bonding.

4. the second transistor comprises a metal oxide; 4. The semiconductor device according to claim 1, wherein the metal oxide comprises indium.

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