Patents by Inventor Kiyoshi Kato

Kiyoshi Kato has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20220328092
    Abstract: A memory device having long data retention time and high reliability is provided. The memory device includes a driver circuit and a plurality of memory cells, the memory cell includes a transistor and a capacitor, and the transistor includes a metal oxide in a channel formation region. The transistor includes a first gate and a second gate, and in a period during which the memory cell retains data, negative potentials are applied to the first gate and the second gate of the transistor.
    Type: Application
    Filed: June 27, 2022
    Publication date: October 13, 2022
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Shunpei YAMAZAKI, Kiyoshi KATO, Takahiko ISHIZU, Tatsuya ONUKI
  • Patent number: 11456296
    Abstract: An object of one embodiment of the present invention is to provide a semiconductor device with a novel structure in which stored data can be stored even when power is not supplied in a data storing time and there is no limitation on the number of times of writing. The semiconductor device includes a first transistor which includes a first channel formation region using a semiconductor material other than an oxide semiconductor, a second transistor which includes a second channel formation region using an oxide semiconductor material, and a capacitor. One of a second source electrode and a second drain electrode of the second transistor is electrically connected to one electrode of the capacitor.
    Type: Grant
    Filed: February 3, 2020
    Date of Patent: September 27, 2022
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Jun Koyama, Kiyoshi Kato
  • Patent number: 11457167
    Abstract: Provided is a comparison circuit to which a negative voltage to be compared can be input directly. The comparison circuit includes a first input terminal, a second input terminal, a first output terminal, and a differential pair. The comparison circuit compares a negative voltage and a negative reference voltage and outputs a first output voltage from the first output terminal in response to the comparison result. The negative voltage is input to the first input terminal. A positive reference voltage is input to the second input terminal. The positive reference voltage is determined so that comparison is performed. The differential pair includes a first n-channel transistor and a second n-channel transistor each having a gate and a backgate. The first input terminal is electrically connected to the backgate of the first n-channel transistor. The second input terminal is electrically connected to the gate of the second n-channel transistor.
    Type: Grant
    Filed: May 22, 2018
    Date of Patent: September 27, 2022
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Takanori Matsuzaki, Kiyoshi Kato
  • Publication number: 20220293159
    Abstract: A semiconductor device in which a memory region at each level of a memory device can be changed is provided. The semiconductor device includes a memory device including a first and a second memory circuit and a control circuit. The first memory circuit includes a first capacitor and a first transistor which has a function of holding charges held in the first capacitor. The second memory circuit includes a second transistor, a second capacitor which is electrically connected to a gate of the second transistor, and a third transistor which has a function of holding charges held in the second capacitor. The first and the third transistors each have a semiconductor layer including an oxide semiconductor, a gate, and a back gate. The voltage applied to the back gate of the first or the third transistor is adjusted, whereby the memory region of each of the first and the second memory circuit is changed.
    Type: Application
    Filed: June 1, 2022
    Publication date: September 15, 2022
    Inventors: Shunpei YAMAZAKI, Kiyoshi KATO, Hajime KIMURA, Atsushi MIYAGUCHI, Tatsunori INOUE
  • Patent number: 11424246
    Abstract: It is an object to provide a memory device whose power consumption can be suppressed and a semiconductor device including the memory device. As a switching element for holding electric charge accumulated in a transistor which functions as a memory element, a transistor including an oxide semiconductor film as an active layer is provided for each memory cell in the memory device. The transistor which is used as a memory element has a first gate electrode, a second gate electrode, a semiconductor film located between the first gate electrode and the second gate electrode, a first insulating film located between the first gate electrode and the semiconductor film, a second insulating film located between the second gate electrode and the semiconductor film, and a source electrode and a drain electrode in contact with the semiconductor film.
    Type: Grant
    Filed: October 2, 2020
    Date of Patent: August 23, 2022
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Yutaka Shionoiri, Hiroyuki Miyake, Kiyoshi Kato
  • Publication number: 20220264044
    Abstract: Provided is a comparison circuit to which a negative voltage to be compared can be input directly. The comparison circuit includes a first input terminal, a second input terminal, a first output terminal, and a differential pair. The comparison circuit compares a negative voltage and a negative reference voltage and outputs a first output voltage from the first output terminal in response to the comparison result. The negative voltage is input to the first input terminal. A positive reference voltage is input to the second input terminal. The positive reference voltage is determined so that comparison is performed. The differential pair includes a first n-channel transistor and a second n-channel transistor each having a gate and a backgate. The first input terminal is electrically connected to the backgate of the first n-channel transistor. The second input terminal is electrically connected to the gate of the second n-channel transistor.
    Type: Application
    Filed: May 9, 2022
    Publication date: August 18, 2022
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Takanori MATSUZAKI, Kiyoshi KATO
  • Patent number: 11410716
    Abstract: A novel storage device and a novel semiconductor device are provided. In the storage device, a cell array including a plurality of memory cells is stacked above a control circuit, and the cell array operates separately in a plurality of blocks. Furthermore, a plurality of electrodes are included between the control circuit and the cell array. The electrode is provided for a corresponding block to overlap with the block, and a potential of the electrode can be changed for each block. The electrode has a function of aback gate of a transistor included in the memory cell, and a potential of the electrode is changed for each block, whereby the electrical characteristics of the transistor included in the memory cell can be changed. Moreover, the electrode can reduce noise caused in the control circuit.
    Type: Grant
    Filed: January 14, 2019
    Date of Patent: August 9, 2022
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Kiyoshi Kato, Tomoaki Atsumi, Shuhei Nagatsuka, Hitoshi Kunitake
  • Patent number: 11404107
    Abstract: A memory device having long data retention time and high reliability is provided. The memory device includes a driver circuit and a plurality of memory cells, the memory cell includes a transistor and a capacitor, and the transistor includes a metal oxide in a channel formation region. The transistor includes a first gate and a second gate, and in a period during which the memory cell retains data, negative potentials are applied to the first gate and the second gate of the transistor.
    Type: Grant
    Filed: March 20, 2019
    Date of Patent: August 2, 2022
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Kiyoshi Kato, Takahiko Ishizu, Tatsuya Onuki
  • Patent number: 11366507
    Abstract: To reduce the area of a memory cell having a backup function. A storage device includes a cell array, and a row circuit and a column circuit that drive the cell array. The cell array includes a first power supply line, a second power supply line, a word line, a pair of bit lines, a memory cell, and a backup circuit. The cell array is located in a power domain where power gating can be performed. In the power gating sequence of the cell array, data in the memory cell is backed up to the backup circuit. The backup circuit is stacked over a region where the memory cell is formed. A plurality of wiring layers are provided between the backup circuit and the memory cell. The first power supply line, the second power supply line, the word line, and the pair of bit lines are located in different wiring layers.
    Type: Grant
    Filed: November 25, 2020
    Date of Patent: June 21, 2022
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shuhei Maeda, Shuhei Nagatsuka, Tatsuya Onuki, Kiyoshi Kato
  • Publication number: 20220179407
    Abstract: A monitoring apparatus according to the present invention includes: a predicting unit configured to, based on a correlation model that corresponds to processing executed in a monitored object in accordance with a preset operation plan and represents a mutual relation between one measured value and other measured value measured from the monitored object, predict the other measured value when the one measured value is changed; and a determining unit configured to determine whether or not the predicted other measured value exceeds an allowable value set for the other measured value during the processing executed in the monitored object in accordance with the operation plan.
    Type: Application
    Filed: February 26, 2020
    Publication date: June 9, 2022
    Applicant: NEC Corporation
    Inventor: Kiyoshi KATO
  • Patent number: 11355176
    Abstract: A semiconductor device in which a memory region at each level of a memory device can be changed is provided. The semiconductor device includes a memory device including a first and a second memory circuit and a control circuit. The first memory circuit includes a first capacitor and a first transistor which has a function of holding charges held in the first capacitor. The second memory circuit includes a second transistor, a second capacitor which is electrically connected to a gate of the second transistor, and a third transistor which has a function of holding charges held in the second capacitor. The first and the third transistors each have a semiconductor layer including an oxide semiconductor, a gate, and a back gate. The voltage applied to the back gate of the first or the third transistor is adjusted, whereby the memory region of each of the first and the second memory circuit is changed.
    Type: Grant
    Filed: April 22, 2019
    Date of Patent: June 7, 2022
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Kiyoshi Kato, Hajime Kimura, Atsushi Miyaguchi, Tatsunori Inoue
  • Publication number: 20220149044
    Abstract: An object is to provide a semiconductor device with a novel structure in which stored data can be held even when power is not supplied and there is no limit on the number of write operations. The semiconductor device includes a first memory cell including a first transistor and a second transistor, a second memory cell including a third transistor and a fourth transistor, and a driver circuit. The first transistor and the second transistor overlap at least partly with each other. The third transistor and the fourth transistor overlap at least partly with each other. The second memory cell is provided over the first memory cell. The first transistor includes a first semiconductor material. The second transistor, the third transistor, and the fourth transistor include a second semiconductor material.
    Type: Application
    Filed: January 20, 2022
    Publication date: May 12, 2022
    Inventor: Kiyoshi KATO
  • Publication number: 20220149045
    Abstract: An object is to provide a semiconductor device with a novel structure. The semiconductor device includes a first wiring; a second wiring; a third wiring; a fourth wiring; a first transistor having a first gate electrode, a first source electrode, and a first drain electrode; and a second transistor having a second gate electrode, a second source electrode, and a second drain electrode. The first transistor is provided in a substrate including a semiconductor material. The second transistor includes an oxide semiconductor layer.
    Type: Application
    Filed: January 24, 2022
    Publication date: May 12, 2022
    Inventors: Shunpei YAMAZAKI, Jun KOYAMA, Kiyoshi KATO
  • Publication number: 20220147032
    Abstract: A monitoring apparatus according to the present invention includes: a detecting unit configured to detect that a monitored object is in a preset specific state based on a plurality of measured values measured from the monitored object; and a specifying unit configured to specify, among elements causing the measured values, the element related to detection of the specific state of the monitored object based on the measured values, and also specify the element based on preset properties of the elements of the measured values.
    Type: Application
    Filed: February 26, 2020
    Publication date: May 12, 2022
    Applicant: NEC Corporation
    Inventor: Kiyoshi KATO
  • Publication number: 20220139917
    Abstract: A novel memory device is provided. The memory device includes a transistor and a capacitor device. The transistor includes a first oxide semiconductor; a first conductor and a second conductor provided over a top surface of the first oxide semiconductor; a second oxide semiconductor that is formed over the first oxide semiconductor and is provided between the first conductor and the second conductor; a first insulator provided in contact with the second oxide semiconductor; and a third conductor provided in contact with the first insulator. The capacitor device includes the second conductor; a second insulator over the second conductor; and a fourth conductor over the second insulator. The first oxide semiconductor has a groove deeper than a thickness of each of the first conductor and the second conductor.
    Type: Application
    Filed: November 15, 2019
    Publication date: May 5, 2022
    Inventors: Shunpei YAMAZAKI, Kiyoshi KATO, Tatsuya ONUKI
  • Patent number: 11322498
    Abstract: An object is to provide a semiconductor device with a novel structure. The semiconductor device includes a first wiring; a second wiring; a third wiring; a fourth wiring; a first transistor having a first gate electrode, a first source electrode, and a first drain electrode; and a second transistor having a second gate electrode, a second source electrode, and a second drain electrode. The first transistor is provided in a substrate including a semiconductor material. The second transistor includes an oxide semiconductor layer.
    Type: Grant
    Filed: July 31, 2020
    Date of Patent: May 3, 2022
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Jun Koyama, Kiyoshi Kato
  • Publication number: 20220128984
    Abstract: A monitoring apparatus according to the present invention includes: a control unit configured to confirm whether a measured value detected from a monitored object satisfies a preset condition, and execute processing for the monitored object set correspondingly to the condition in a case where the measured value satisfies the condition; and a recording processing unit configured to record an execution status of the processing for the monitored object into preset schedule data.
    Type: Application
    Filed: February 26, 2020
    Publication date: April 28, 2022
    Applicant: NEC Corporation
    Inventor: Kiyoshi KATO
  • Publication number: 20220108985
    Abstract: A memory device including a gain-cell memory cell capable of storing a large amount of data per unit area is provided. A peripheral circuit of the memory device is formed using a transistor formed on a semiconductor substrate, and a memory cell of the memory device is formed using a thin film transistor. A plurality of layers including thin film transistors where memory cells are formed are stacked above the semiconductor substrate, whereby the amount of data that can be stored per unit area can be increased. When an OS transistor with extremely low off-state current is used as the thin film transistor, the capacitance of a capacitor that accumulates charge can be reduced. In other words, the area of the memory cell can be reduced.
    Type: Application
    Filed: November 22, 2019
    Publication date: April 7, 2022
    Inventors: Shuhei NAGATSUKA, Tatsuya ONUKI, Takahiko ISHIZU, Kiyoshi KATO, Shunpei YAMAZAKI
  • Publication number: 20220093141
    Abstract: A semiconductor device with a high on-state current and high operating speed is provided. The semiconductor device includes a transistor and a first circuit. The transistor includes a first gate and a second gate, and the first gate and the second gate include a region where they overlap each other with a semiconductor layer therebetween. The first circuit includes a temperature sensor and a voltage control circuit. The temperature sensor has a function of obtaining temperature information and outputting the temperature information to the voltage control circuit. The voltage control circuit has a function of converting the temperature information into a control voltage. The first circuit applies the control voltage to the second gate.
    Type: Application
    Filed: December 2, 2021
    Publication date: March 24, 2022
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Tomoaki ATSUMI, Kiyoshi KATO, Tatsuya ONUKI, Shunpei YAMAZAKI
  • Publication number: 20220085020
    Abstract: A novel memory device is provided. Over a driver circuit layer, N memory layers (N is a natural number greater than or equal to 2) including a plurality of memory cells provided in a matrix are stacked. The memory cell includes two transistors and one capacitor. An oxide semiconductor is used as a semiconductor included in the transistor. The memory cell is electrically connected to a write word line, a selection line, a capacitor line, a write bit line, and a read bit line. The write bit line and the read bit line extend in the stacking direction, whereby the signal propagation distance from the memory cell to the driver circuit layer is shortened.
    Type: Application
    Filed: November 18, 2019
    Publication date: March 17, 2022
    Inventors: Shuhei NAGATSUKA, Tatsuya ONUKI, Kiyoshi KATO, Shunpei YAMAZAKI