Patents by Inventor Masaki Shiraishi

Masaki Shiraishi 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: 20240055423
    Abstract: A semiconductor device that is equipped with a MOSFET with a Zener diode embedded and capable of achieving both improvement in the surge resistance and the low on-resistance of the MOSFET is provided. The semiconductor device equipped with a MOSFET with a Zener diode embedded includes an active region in which the MOSFET operates, and a peripheral region that is disposed outside of the active region and holds a withstand voltage of a chip peripheral portion, in which the active region includes a first region including a chip central portion and a second region disposed outside of the first region, and a withstand voltage of the first region is lower than a withstand voltage of the second region and a withstand voltage of the peripheral region.
    Type: Application
    Filed: October 6, 2020
    Publication date: February 15, 2024
    Applicant: Hitachi Power Semiconductor Device, Ltd.
    Inventors: Masaki SHIRAISHI, Junichi SAKANO
  • Patent number: 11881514
    Abstract: Provided is a highly reliable semiconductor device in which an influence on device characteristics can be reduced while improving a high temperature and high humidity bias resistance of a termination structure (termination region) of a chip by a relatively simple method. The semiconductor device includes an active region disposed on a main surface of a semiconductor substrate, and a termination region disposed on the main surface so as to surround the active region. The termination region includes an interlayer insulating film formed on the main surface of the semiconductor substrate, and an organic protective film formed so as to cover the interlayer insulating film. An insulating film having a thickness of 100 nm or less and containing nitrogen is provided between the interlayer insulating film and the organic protective film.
    Type: Grant
    Filed: November 22, 2021
    Date of Patent: January 23, 2024
    Assignee: HITACHI POWER SEMICONDUCTOR DEVICE, LTD.
    Inventors: Shigeo Tokumitsu, Masaki Shiraishi, Yutaka Kato, Tetsuo Oda
  • Patent number: 11843036
    Abstract: Provided is a highly reliable semiconductor device in which an influence on device characteristics can be reduced while improving a high temperature and high humidity bias resistance of a termination structure (termination region) of a chip by a relatively simple method. The semiconductor device includes an active region disposed on a main surface of a semiconductor substrate, and a termination region disposed on the main surface so as to surround the active region. The termination region includes an interlayer insulating film formed on the main surface of the semiconductor substrate, and an organic protective film formed so as to cover the interlayer insulating film. An insulating film having a thickness of 100 nm or less and containing nitrogen is provided between the interlayer insulating film and the organic protective film.
    Type: Grant
    Filed: November 22, 2021
    Date of Patent: December 12, 2023
    Assignee: HITACHI POWER SEMICONDUCTOR DEVICE, LTD.
    Inventors: Shigeo Tokumitsu, Masaki Shiraishi, Yutaka Kato, Tetsuo Oda
  • Patent number: 11757444
    Abstract: A semiconductor element drive device is provided to solve a problem that because a case of a change in the temperature of the semiconductor element or a current flowing through the semiconductor element is not take into consideration, switching loss and noise cannot be reduced sufficiently. In accordance with input sensing information (temperature T, current I), a timing control unit 3 outputs a delay signal Q to control timing of driving a current increasing circuit 5 so that a reduction of switching loss of an IGBT 101 is maximized. When the IGBT 101 is in turn-on mode or turn-off mode, the current increasing circuit 5 outputs a drive signal in response to the delay signal Q delayed by a given time from output of the drive instruction signal P. In this way, the current increasing circuit 5 increases the current that causes the gate capacitor of the IGBT 101 to be charged/discharged in response to the delay signal Q, thereby increasing a switching speed to reduce switching loss.
    Type: Grant
    Filed: December 18, 2020
    Date of Patent: September 12, 2023
    Assignee: Hitachi Astemo, Ltd.
    Inventors: Hiroshi Suzuki, Masaki Shiraishi, Koichi Yahata
  • Publication number: 20220278194
    Abstract: A semiconductor device having a high cutoff resistance capable of suppressing local current/electric field concentration and current concentration at a chip termination portion due to an electric field variation between IGBT cells due to a shape variation and impurity variation during manufacturing. The semiconductor device is characterized by including an emitter electrode formed on a front surface of a semiconductor substrate via an interlayer insulating film, a collector electrode formed on a back surface of the semiconductor substrate, a first semiconductor layer of a first conductivity type in contact with the collector electrode, a second semiconductor layer of a second conductivity type, a central area cell, and an outer peripheral area cell located outside the central area cell.
    Type: Application
    Filed: April 22, 2020
    Publication date: September 1, 2022
    Applicant: Hitachi Power Semiconductor Device, Ltd.
    Inventors: Tomoyasu Furukawa, Masaki Shiraishi, So Watanabe, Tomoyuki Miyoshi, Yujiro Takeuchi
  • Publication number: 20220199786
    Abstract: Provided is a highly reliable semiconductor device in which an influence on device characteristics can be reduced while improving a high temperature and high humidity bias resistance of a termination structure (termination region) of a chip by a relatively simple method. The semiconductor device includes an active region disposed on a main surface of a semiconductor substrate, and a termination region disposed on the main surface so as to surround the active region. The termination region includes an interlayer insulating film formed on the main surface of the semiconductor substrate, and an organic protective film formed so as to cover the interlayer insulating film. An insulating film having a thickness of 100 nm or less and containing nitrogen is provided between the interlayer insulating film and the organic protective film.
    Type: Application
    Filed: November 22, 2021
    Publication date: June 23, 2022
    Applicant: Hitachi Power Semiconductor Device, Ltd.
    Inventors: Shigeo Tokumitsu, Masaki Shiraishi, Yutaka Kato, Tetsuo Oda
  • Patent number: 11296212
    Abstract: A current switching semiconductor device to be used in a power conversion device achieves both a low conduction loss and a low switching loss. The semiconductor device includes the IGBT in which only Gc gates are provided and an impurity concentration of the p type collector layer is high, and the IGBT in which the Gs gates and the Gc gates are provided and an impurity concentration of the p type collector layer is low. When the semiconductor device is turned off, the semiconductor device transitions from a state in which a voltage lower than a threshold voltage is applied to both the Gs gates and the Gc gates to a state in which a voltage equal to or higher than the threshold voltage is applied to the Gc gates prior to the Gs gates.
    Type: Grant
    Filed: February 1, 2019
    Date of Patent: April 5, 2022
    Assignee: Hitachi Power Semiconductor Device, Ltd.
    Inventors: Tomoyuki Miyoshi, Mutsuhiro Mori, Tomoyasu Furukawa, Yujiro Takeuchi, Masaki Shiraishi
  • Patent number: 11282937
    Abstract: The invention provides an inexpensive flywheel diode having a low power loss. A semiconductor substrate side of a gate electrode provided on a surface of an anode electrode side of a semiconductor substrate including silicon is surrounded by a p layer, an n layer, and a p layer via a gate insulating film. The anode electrode is in contact with the p layer with a low resistance, and is also in contact with the n layer or the p layer, and a Schottky diode is formed between the anode electrode and the n layer or the p layer.
    Type: Grant
    Filed: February 1, 2019
    Date of Patent: March 22, 2022
    Assignee: Hitachi Power Semiconductor Device, Ltd.
    Inventors: Mutsuhiro Mori, Tomoyuki Miyoshi, Tomoyasu Furukawa, Masaki Shiraishi
  • Patent number: 11049965
    Abstract: A semiconductor device includes a first external electrode with a first electrode surface portion; a second external electrode with a second electrode surface portion; a MOSFET chip with a built-in Zener diode which includes an active region and a peripheral region; a control IC chip which drives the MOSFET chip based on voltage or current between a drain electrode and a source electrode of the MOSFET chip; and a capacitor which supplies power to the MOSFET chip and the control IC chip. The first electrode surface portion is connected to either the drain electrode or the source, the second electrode surface portion is connected to either the source electrode or the drain electrode, a plurality of unit cells of the MOSFET with the built-in Zener diode are provided in the active region, and the breakdown voltage of the Zener diode is set to be lower than that of the peripheral region.
    Type: Grant
    Filed: August 6, 2018
    Date of Patent: June 29, 2021
    Assignee: HITACHI POWER SEMICONDUCTOR DEVICE, LTD.
    Inventors: Masaki Shiraishi, Tetsuya Ishimaru, Junichi Sakano, Mutsuhiro Mori, Shinichi Kurita
  • Publication number: 20210091217
    Abstract: A current switching semiconductor device to be used in a power conversion device achieves both a low conduction loss and a low switching loss. The semiconductor device includes the IGBT in which only Gc gates are provided and an impurity concentration of the p type collector layer is high, and the IGBT in which the Gs gates and the Gc gates are provided and an impurity concentration of the p type collector layer is low. When the semiconductor device is turned off, the semiconductor device transitions from a state in which a voltage lower than a threshold voltage is applied to both the Gs gates and the Gc gates to a state in which a voltage equal to or higher than the threshold voltage is applied to the Gc gates prior to the Gs gates.
    Type: Application
    Filed: February 1, 2019
    Publication date: March 25, 2021
    Inventors: Tomoyuki MIYOSHI, Mutsuhiro MORI, Tomoyasu FURUKAWA, Yujiro TAKEUCHI, Masaki SHIRAISHI
  • Publication number: 20210057537
    Abstract: The invention provides an inexpensive flywheel diode having a low power loss. A semiconductor substrate side of a gate electrode provided on a surface of an anode electrode side of a semiconductor substrate including silicon is surrounded by a p layer, an n layer, and a p layer via a gate insulating film. The anode electrode is in contact with the p layer with a low resistance, and is also in contact with the n layer or the p layer, and a Schottky diode is formed between the anode electrode and the n layer or the p layer.
    Type: Application
    Filed: February 1, 2019
    Publication date: February 25, 2021
    Inventors: Mutsuhiro MORI, Tomoyuki MIYOSHI, Tomoyasu FURUKAWA, Masaki SHIRAISHI
  • Patent number: 10763346
    Abstract: Provided is a semiconductor device in which, in a case where a metallic plate (a conductive member) is bonded by being sintered to a semiconductor chip having an IGBT gate structure, an excess stress is less likely to be generated in a gate wiring section of the semiconductor chip even when pressure is applied in a sinter bonding process, so that a characteristic failure is reduced.
    Type: Grant
    Filed: December 25, 2017
    Date of Patent: September 1, 2020
    Assignee: Hitachi Power Semiconductor Device, Ltd.
    Inventors: Tomoyasu Furukawa, Masaki Shiraishi, Toshiaki Morita
  • Publication number: 20200006301
    Abstract: Provided is a semiconductor device in which, in a case where a metallic plate (a conductive member) is bonded by being sintered to a semiconductor chip having an IGBT gate structure, an excess stress is less likely to be generated in a gate wiring section of the semiconductor chip even when pressure is applied in a sinter bonding process, so that a characteristic failure is reduced.
    Type: Application
    Filed: December 25, 2017
    Publication date: January 2, 2020
    Inventors: Tomoyasu FURUKAWA, Masaki SHIRAISHI, Toshiaki MORITA
  • Patent number: 10204899
    Abstract: In a non-insulated DC-DC converter having a circuit in which a power MOS?FET high-side switch and a power MOS?FET low-side switch are connected in series, the power MOS?FET low-side switch and a Schottky barrier diode to be connected in parallel with the power MOS?FET low-side switch are formed within one semiconductor chip. The formation region SDR of the Schottky barrier diode is disposed in the center in the shorter direction of the semiconductor chip, and on both sides thereof, the formation regions of the power MOS?FET low-side switch are disposed. From the gate finger in the vicinity of both long sides on the main surface of the semiconductor chip toward the formation region SDR of the Schottky barrier diode, a plurality of gate fingers are disposed so as to interpose the formation region SDR between them.
    Type: Grant
    Filed: September 11, 2017
    Date of Patent: February 12, 2019
    Assignee: Renesas Electronics Corporation
    Inventors: Masaki Shiraishi, Tomoaki Uno, Nobuyoshi Matsuura
  • Publication number: 20190043984
    Abstract: A semiconductor device includes a first external electrode with a first electrode surface portion; a second external electrode with a second electrode surface portion; a MOSFET chip with a built-in Zener diode which includes an active region and a peripheral region; a control IC chip which drives the MOSFET chip based on voltage or current between a drain electrode and a source electrode of the MOSFET chip; and a capacitor which supplies power to the MOSFET chip and the control IC chip. The first electrode surface portion is connected to either the drain electrode or the source, the second electrode surface portion is connected to either the source electrode or the drain electrode, a plurality of unit cells of the MOSFET with the built-in Zener diode are provided in the active region, and the breakdown voltage of the Zener diode is set to be lower than that of the peripheral region.
    Type: Application
    Filed: August 6, 2018
    Publication date: February 7, 2019
    Applicant: HITACHI POWER SEMICONDUCTOR DEVICE, LTD.
    Inventors: Masaki SHIRAISHI, Tetsuya ISHIMARU, Junichi SAKANO, Mutsuhiro MORI, Shinichi KURITA
  • Publication number: 20170373055
    Abstract: In a non-insulated DC-DC converter having a circuit in which a power MOS•FET high-side switch and a power MOS•FET low-side switch are connected in series, the power MOS•FET low-side switch and a Schottky barrier diode to be connected in parallel with the power MOS•FET low-side switch are formed within one semiconductor chip. The formation region SDR of the Schottky barrier diode is disposed in the center in the shorter direction of the semiconductor chip, and on both sides thereof, the formation regions of the power MOS•FET low-side switch are disposed. From the gate finger in the vicinity of both long sides on the main surface of the semiconductor chip toward the formation region SDR of the Schottky barrier diode, a plurality of gate fingers are disposed so as to interpose the formation region SDR between them.
    Type: Application
    Filed: September 11, 2017
    Publication date: December 28, 2017
    Inventors: Masaki SHIRAISHI, Tomoaki UNO, Nobuyoshi MATSUURA
  • Patent number: 9793265
    Abstract: In a non-insulated DC-DC converter having a circuit in which a power MOS•FET high-side switch and a power MOS•FET low-side switch are connected in series, the power MOS•FET low-side switch and a Schottky barrier diode to be connected in parallel with the power MOS•FET low-side switch are formed within one semiconductor chip. The formation region SDR of the Schottky barrier diode is disposed in the center in the shorter direction of the semiconductor chip, and on both sides thereof, the formation regions of the power MOS•FET low-side switch are disposed. From the gate finger in the vicinity of both long sides on the main surface of the semiconductor chip toward the formation region SDR of the Schottky barrier diode, a plurality of gate fingers are disposed so as to interpose the formation region SDR between them.
    Type: Grant
    Filed: September 15, 2016
    Date of Patent: October 17, 2017
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Masaki Shiraishi, Tomoaki Uno, Nobuyoshi Matsuura
  • Publication number: 20170005089
    Abstract: In a non-insulated DC-DC converter having a circuit in which a power MOS•FET high-side switch and a power MOS•FET low-side switch are connected in series, the power MOS•FET low-side switch and a Schottky barrier diode to be connected in parallel with the power MOS•FET low-side switch are formed within one semiconductor chip. The formation region SDR of the Schottky barrier diode is disposed in the center in the shorter direction of the semiconductor chip, and on both sides thereof, the formation regions of the power MOS•FET low-side switch are disposed. From the gate finger in the vicinity of both long sides on the main surface of the semiconductor chip toward the formation region SDR of the Schottky barrier diode, a plurality of gate fingers are disposed so as to interpose the formation region SDR between them.
    Type: Application
    Filed: September 15, 2016
    Publication date: January 5, 2017
    Inventors: Masaki SHIRAISHI, Tomoaki UNO, Nobuyoshi MATSUURA
  • Patent number: 9461163
    Abstract: In a non-insulated DC-DC converter having a circuit in which a power MOS•FET high-side switch and a power MOS•FET low-side switch are connected in series, the power MOS•FET low-side switch and a Schottky barrier diode to be connected in parallel with the power MOS•FET low-side switch are formed within one semiconductor chip. The formation region SDR of the Schottky barrier diode is disposed in the center in the shorter direction of the semiconductor chip, and on both sides thereof, the formation regions of the power MOS•FET low-side switch are disposed. From the gate finger in the vicinity of both long sides on the main surface of the semiconductor chip toward the formation region SDR of the Schottky barrier diode, a plurality of gate fingers are disposed so as to interpose the formation region SDR between them.
    Type: Grant
    Filed: September 17, 2015
    Date of Patent: October 4, 2016
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Masaki Shiraishi, Tomoaki Uno, Nobuyoshi Matsuura
  • Publication number: 20160254761
    Abstract: A semiconductor device includes a semiconductor substrate in which a semiconductor element is formed, an electrode structure of a first semiconductor chip which is provided on a first surface of an n+-type semiconductor layer of the semiconductor substrate to be electrically connected to the semiconductor element and in which a first Al metal layer composed of Al or Al alloy, a Cu diffusion-prevention layer, a second Al metal layer composed of Al or Al alloy, and a Ni layer are formed in this order, and a conductive member which is bonded to the electrode structure of the first semiconductor chip via a sintered copper layer disposed on a surface of the Ni layer. In this semiconductor device, a crystal plane orientation of Al crystal grains on a surface of the second Al metal layer is principally on (110) plane.
    Type: Application
    Filed: February 24, 2016
    Publication date: September 1, 2016
    Inventors: Tomoyasu FURUKAWA, Masaki SHIRAISHI, Hiroshi NAKANO, Toshiaki MORITA