Patents by Inventor Shuhei Nagatsuka

Shuhei Nagatsuka 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).

  • Patent number: 10217736
    Abstract: A highly integrated semiconductor device including a transistor and a capacitor which occupies a small area for the required on-state current and required capacitance is provided. The semiconductor device includes a semiconductor, first and second conductive films each in contact with top and side surfaces of the semiconductor, a first insulating film in contact with the top and side surfaces of the semiconductor, a third conductive film facing the top and side surfaces of the semiconductor with the first insulating film therebetween, a second insulating film which is in contact with the first conductive film and comprises an opening, a fourth conductive film in contact with the opening, a third insulating film facing the opening with the fourth conductive film therebetween, and a fifth conductive film facing the fourth conductive film with the third insulating film therebetween.
    Type: Grant
    Filed: September 22, 2014
    Date of Patent: February 26, 2019
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Kiyoshi Kato, Hidekazu Miyairi, Shuhei Nagatsuka
  • Patent number: 10217752
    Abstract: [Problem] To provide a semiconductor device suitable for miniaturization. To provide a highly reliable semiconductor device. To provide a semiconductor device with improved operating speed. [Solving Means] A semiconductor device including a memory cell including first to cth (c is a natural number of 2 or more) sub memory cells, wherein: the jth sub memory cell includes a first transistor, a second transistor, and a capacitor; a first semiconductor layer included in the first transistor and a second semiconductor layer included in the second transistor include an oxide semiconductor; one of terminals of the capacitor is electrically connected to a gate electrode included in the second transistor; the gate electrode included in the second transistor is electrically connected to one of a source electrode and a drain electrode which are included in the first transistor; and when j?2, the jth sub memory cell is arranged over the j?1th sub memory cell.
    Type: Grant
    Filed: May 10, 2017
    Date of Patent: February 26, 2019
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Tomoaki Atsumi, Shuhei Nagatsuka, Tamae Moriwaka, Yuta Endo
  • Patent number: 10109371
    Abstract: The semiconductor device includes a bit line, a transistor, a retention node, and a capacitor. The transistor has a function of charging or discharging the retention node. The capacitor has a function of retaining a potential of the retention node. A voltage greater than the sum of a writing voltage and a threshold voltage is applied to a gate of the transistor. When the transistor is turned on, a first potential is supplied to the bit line with a reference potential in a floating state. A voltage less than the sum of the writing voltage and the threshold voltage is applied to the gate of the transistor. When the transistor is turned on, a second potential is supplied to the bit line with a reference potential in a floating state. With use of the first and second potentials, the threshold voltage of the transistor is calculated without being influenced by parasitic capacitance and variations in the storage capacitance of the capacitor.
    Type: Grant
    Filed: December 28, 2016
    Date of Patent: October 23, 2018
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Tomoaki Atsumi, Shuhei Nagatsuka, Kazuaki Ohshima
  • Patent number: 10050060
    Abstract: To provide a semiconductor device with excellent electrical characteristics or a semiconductor device with stable electrical characteristics. A semiconductor device includes a first transistor, a second transistor, a first insulator, a second insulator, a first wiring, and a first plug. The first transistor includes silicon. The second transistor includes an oxide semiconductor. The first insulator is located over the first transistor. The second insulator is located over the first insulator. The second transistor is located over the second insulator. The first wiring is located over the second insulator and the first plug. The first transistor and the second transistor are electrically connected to each other through the first wiring and the first plug. The first wiring has low hydrogen permeability. The hydrogen permeability of the second insulator is lower than the hydrogen permeability of the first insulator.
    Type: Grant
    Filed: May 10, 2017
    Date of Patent: August 14, 2018
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hidekazu Miyairi, Yuichi Sato, Yuji Asano, Tetsunori Maruyama, Tatsuya Onuki, Shuhei Nagatsuka
  • Publication number: 20180197889
    Abstract: To provide a semiconductor device that is not easily damaged by ESD in a manufacturing process thereof. A layer whose band gap is greater than or equal to 2.5 eV and less than or equal to 4.2 eV, preferably greater than or equal to 2.7 eV and less than or equal to 3.5 eV is provided to overlap with a dicing line. A layer whose band gap is greater than or equal to 2.5 eV and less than or equal to 4.2 eV, preferably greater than or equal to 2.7 eV and less than or equal to 3.5 eV is provided around the semiconductor device such as a transistor. The layer may be in a floating state or may be supplied with a specific potential.
    Type: Application
    Filed: March 5, 2018
    Publication date: July 12, 2018
    Inventors: Shunpei Yamazaki, Kiyoshi Kato, Yuto Yakubo, Shuhei Nagatsuka
  • Patent number: 10002648
    Abstract: A column driver includes an amplifier circuit for amplifying data of a read bit line and a latch circuit for retaining the amplified data. The latch circuit includes a pair of nodes Q and QB for retaining complementary data. Data is read from a memory cell in each write target row to a read bit line, and amplified by the amplifier circuit. The amplified data is written to the node Q (or QB) of the latch circuit. In a write target column, write data is input to the latch circuit through the node Q (or QB) to update data of the latch circuit. Then, in each column, data of the latch circuit is written to a write bit line, and the data of the write bit line is written to the memory cell.
    Type: Grant
    Filed: March 2, 2017
    Date of Patent: June 19, 2018
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Takahiko Ishizu, Shuhei Nagatsuka
  • Publication number: 20180114578
    Abstract: A data reading error is reduced. A memory cell array in a storage device includes a write word line, a read word line, a write bit line, a read bit line, a source line, and a gain cell. For example, a read transistor in the gain cell can include a metal oxide in a channel formation region. A cancel circuit is electrically connected to the read bit line. The cancel circuit has a function of supplying, to the read bit line, current for canceling leakage current supplied to the read bit line from the gain cell in a non-selected state. In read operation, a potential change of the read bit line due to leakage current is compensated for by the current from the cancel circuit, so that a data reading error is reduced.
    Type: Application
    Filed: October 16, 2017
    Publication date: April 26, 2018
    Inventors: Takahiko ISHIZU, Shuhei NAGATSUKA
  • Patent number: 9954003
    Abstract: A semiconductor device with high design flexibility is provided. A first transistor and a second transistor having electrical characteristics different from those of the first transistor are provided over the same layer without significantly increasing the number of manufacturing steps. For example, semiconductor materials with different electron affinities are used for a semiconductor layer in which a channel of the first transistor is formed and a semiconductor layer in which a channel of the second transistor is formed. This allows the threshold voltages of the first transistor and the second transistor to differ from each other. Forming a gate electrode using a damascene process enables miniaturization and high density of the transistors. Furthermore, a highly-integrated semiconductor device is provided.
    Type: Grant
    Filed: February 13, 2017
    Date of Patent: April 24, 2018
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shinpei Matsuda, Masayuki Sakakura, Yuki Hata, Shuhei Nagatsuka, Yuta Endo, Shunpei Yamazaki
  • Publication number: 20180090976
    Abstract: An electric power charge and discharge system for an electronic device having a battery, by which the electronic device can be used for a long period of time. In a wireless communication device including a wireless driving portion including a first battery and a wireless charging portion including a second battery, the first battery is charged by electric power from a fixed power supply and the second battery is charged by using electromagnetic waves existing in an external space. Further, the first battery and the second battery are discharged alternately, and during a period in which the first battery is discharged, the second battery is charged.
    Type: Application
    Filed: November 27, 2017
    Publication date: March 29, 2018
    Inventors: Shuhei NAGATSUKA, Akihiro KIMURA
  • Publication number: 20180075900
    Abstract: A memory device includes a memory cell, a replica cell, a read circuit, a write wordline, a read wordline, a dummy read wordline, a write bitline, a read bitline, a reference bitline, a sourceline, and a first wiring. The memory cell is electrically connected to the write wordline, the read wordline, the write bitline, the read bitline, and the sourceline. The read circuit outputs a potential based on the result of comparing the potential of the reference bitline and the potential of the read bitline. The replica cell includes a first transistor and a second transistor. The first transistor and the second transistor are electrically connected to each other in series between the bitline and the sourceline. A gate of the first transistor and a gate of the second transistor are electrically connected to a dummy read wordline and the first wiring, respectively.
    Type: Application
    Filed: September 5, 2017
    Publication date: March 15, 2018
    Inventors: Takahiko ISHIZU, Shuhei NAGATSUKA
  • Patent number: 9911756
    Abstract: To provide a semiconductor device that is not easily damaged by ESD in a manufacturing process thereof. A layer whose band gap is greater than or equal to 2.5 eV and less than or equal to 4.2 eV, preferably greater than or equal to 2.7 eV and less than or equal to 3.5 eV is provided to overlap with a dicing line. A layer whose band gap is greater than or equal to 2.5 eV and less than or equal to 4.2 eV, preferably greater than or equal to 2.7 eV and less than or equal to 3.5 eV is provided around the semiconductor device such as a transistor. The layer may be in a floating state or may be supplied with a specific potential.
    Type: Grant
    Filed: August 24, 2016
    Date of Patent: March 6, 2018
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Kiyoshi Kato, Yuto Yakubo, Shuhei Nagatsuka
  • Publication number: 20180033807
    Abstract: A highly reliable semiconductor device capable of retaining data for a long period is provided. The transistor includes a first gate electrode, a first gate insulator over the first gate electrode, a first oxide and a second oxide over the first gate insulator, a first conductor over the first oxide, a second conductor over the second oxide, a third oxide covering the first gate insulator, the first oxide, the first conductor, the second oxide, and the second conductor, a second gate insulator over the third oxide, and a second gate electrode over the second gate insulator. An end portion of the second gate electrode is positioned between an end portion of the first conductor and an end portion of the second conductor in a channel length direction.
    Type: Application
    Filed: July 25, 2017
    Publication date: February 1, 2018
    Inventors: Shinpei MATSUDA, Daigo ITO, Daisuke MATSUBAYASHI, Yasutaka SUZUKI, Etsuko KAMATA, Yutaka SHIONOIRI, Shuhei NAGATSUKA
  • Patent number: 9831707
    Abstract: An electric power charge and discharge system for an electronic device having a battery, by which the electronic device can be used for a long period of time. In a wireless communication device including a wireless driving portion including a first battery and a wireless charging portion including a second battery, the first battery is charged by electric power from a fixed power supply and the second battery is charged by using electromagnetic waves existing in an external space. Further, the first battery and the second battery are discharged alternately, and during a period in which the first battery is discharged, the second battery is charged.
    Type: Grant
    Filed: March 13, 2014
    Date of Patent: November 28, 2017
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shuhei Nagatsuka, Akihiro Kimura
  • Patent number: 9825037
    Abstract: A semiconductor device including a nonvolatile memory cell in which a writing transistor which includes an oxide semiconductor, a reading transistor which includes a semiconductor material different from that of the writing transistor, and a capacitor are included is provided. Data is written to the memory cell by turning on the writing transistor and applying a potential to a node where a source electrode (or a drain electrode) of the writing transistor, one electrode of the capacitor, and a gate electrode of the reading transistor are electrically connected, and then turning off the writing transistor, so that the predetermined amount of charge is held in the node. Further, when a p-channel transistor is used as the reading transistor, a reading potential is a positive potential.
    Type: Grant
    Filed: November 23, 2016
    Date of Patent: November 21, 2017
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hiroki Inoue, Kiyoshi Kato, Takanori Matsuzaki, Shuhei Nagatsuka
  • Patent number: 9793276
    Abstract: A semiconductor device with a novel structure in which stored data can be held even when power is not supplied and there is no limitation on the number of times of writing. In the semiconductor device, a plurality of memory cells each including a first transistor, a second transistor, and a capacitor is provided in matrix and a wiring (also called a bit line) for connecting one memory cell to another memory cell and a source or drain electrode of the first transistor are electrically connected to each other through a source or drain electrode of the second transistor. Accordingly, the number of wirings can be smaller than that in the case where the source or drain electrode of the first transistor and the source or drain electrode of the second transistor are connected to different wirings. Thus, the degree of integration of the semiconductor device can be increased.
    Type: Grant
    Filed: November 9, 2015
    Date of Patent: October 17, 2017
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Kiyoshi Kato, Shuhei Nagatsuka, Hiroki Inoue, Takanori Matsuzaki
  • Publication number: 20170263774
    Abstract: A transistor having favorable electrical characteristics. A transistor suitable for miniaturization. A transistor having a high switching speed. One embodiment of the present invention is a semiconductor device that includes a transistor. The transistor includes an oxide semiconductor, a gate electrode, and a gate insulator. The oxide semiconductor includes a first region in which the oxide semiconductor and the gate electrode overlap with each other with the gate insulator positioned therebetween. The transistor has a threshold voltage higher than 0 V and a switching speed lower than 100 nanoseconds.
    Type: Application
    Filed: May 25, 2017
    Publication date: September 14, 2017
    Inventors: Daisuke MATSUBAYASHI, Yoshiyuki KOBAYASHI, Shuhei NAGATSUKA, Yutaka SHIONOIRI
  • Patent number: 9755643
    Abstract: To provide a semiconductor device that inhibits unexpected output of a high-level signal immediately after the rise of a power supply voltage. The semiconductor device includes a first buffer circuit, a level shifter circuit, and a second buffer circuit. A first potential is supplied to the first buffer circuit, and a second potential is supplied to the level shifter circuit and the second buffer circuit; consequently, the semiconductor device returns to a normal state. When the semiconductor device returns to a normal state, the second potential is supplied, so that the potential of a node in the level shifter circuit increases. To utilize the increase in the second potential or suppress malfunction due to the increase in the potential, capacitors are provided in the level shifter circuit. This inhibits unexpected operation of a transistor in the level shifter circuit.
    Type: Grant
    Filed: December 14, 2015
    Date of Patent: September 5, 2017
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hiroki Inoue, Takanori Matsuzaki, Shuhei Nagatsuka, Takahiko Ishizu, Tatsuya Onuki
  • Patent number: 9747962
    Abstract: A semiconductor device which can write and read multilevel data is provided. A node connecting a source or a drain of an OS transistor and a gate of an OS transistor can hold the distribution of a plurality of potentials. A circuit configuration is employed in which the potential of the node is changed by capacitive coupling to control a conduction state of the OS transistor whose gate is connected thereto so that the potential of a gate of a Si transistor is changed. The potential of the gate of the Si transistor is changed positively in accordance with the potential change by capacitive coupling and is changed negatively in accordance with another transistor. In accordance with a change in value of current flowing through the Si transistor is detected, written data is read.
    Type: Grant
    Filed: March 5, 2015
    Date of Patent: August 29, 2017
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shuhei Nagatsuka, Tomoaki Atsumi, Shunpei Yamazaki
  • Patent number: 9748274
    Abstract: A memory device in which the number of films is reduced. The memory device includes a circuit and a wiring. The circuit includes a first memory cell and a second memory cell. The first memory cell includes a first transistor, a second transistor, and a first capacitor. The second memory cell includes a third transistor, a fourth transistor, and a second capacitor. The second memory cell is stacked over the first memory cell. One of a source and a drain of the first transistor is electrically connected to a gate of the second transistor and the first capacitor. One of a source and a drain of the third transistor is electrically connected to a gate of the fourth transistor and the second capacitor. A gate of the first transistor and a gate of the third transistor are electrically connected to the wiring.
    Type: Grant
    Filed: May 20, 2016
    Date of Patent: August 29, 2017
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Takahiko Ishizu, Shuhei Nagatsuka, Tatsuya Onuki, Yutaka Shionoiri, Naoaki Tsutsui, Shunpei Yamazaki
  • Publication number: 20170243899
    Abstract: To provide a semiconductor device with excellent electrical characteristics or a semiconductor device with stable electrical characteristics. A semiconductor device includes a first transistor, a second transistor, a first insulator, a second insulator, a first wiring, and a first plug. The first transistor includes silicon. The second transistor includes an oxide semiconductor. The first insulator is located over the first transistor. The second insulator is located over the first insulator. The second transistor is located over the second insulator. The first wiring is located over the second insulator and the first plug. The first transistor and the second transistor are electrically connected to each other through the first wiring and the first plug. The first wiring has low hydrogen permeability. The hydrogen permeability of the second insulator is lower than the hydrogen permeability of the first insulator.
    Type: Application
    Filed: May 10, 2017
    Publication date: August 24, 2017
    Inventors: Hidekazu MIYAIRI, Yuichi SATO, Yuji ASANO, Tetsunori MARUYAMA, Tatsuya ONUKI, Shuhei NAGATSUKA