Patents by Inventor Mutsuhiro Mori

Mutsuhiro Mori 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: 20020110008
    Abstract: In a driving apparatus of a power semiconductor element for conducting or interrupting a main current, first resistance variable for changing a first resistance according to a control voltage, and second resistance variable for changing a second resistance according to a voltage between a first and a second terminal are provided, and either one of a voltage of a control power supply or a voltage between the first and the second terminal is voltage-divided by the first resistance and the second resistance, and the divided voltage is applied to a control gate terminal at the time of conducting or interrupting the main current.
    Type: Application
    Filed: April 9, 2002
    Publication date: August 15, 2002
    Inventors: Hideki Miyazaki, Katsunori Suzuki, Koji Tateno, Junichi Sakano, Masahiro Iwamura, Mutsuhiro Mori
  • Patent number: 6414370
    Abstract: A semiconductor circuit or a semiconductor device has the current-voltage characteristic that, in a blocking-state of the semiconductor circuit or the semiconductor device, a current gently flows for values of a voltage equal to or greater than a first voltage value but equal to or smaller than a second voltage value, whereas a current abruptly flows for values of a voltage greater than the second voltage value. Due to the current-voltage characteristic, energy accumulated in an inductance provided within the circuit is consumed by a differential resistance of the semiconductor circuit or a semiconductor, thereby preventing the occurrence of the electromagnetic noise and an excessively large voltage.
    Type: Grant
    Filed: August 17, 2000
    Date of Patent: July 2, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Masahiro Nagasu, Hideo Kobayashi, Hideki Miyazaki, Shin Kimura, Junichi Sakano, Mutsuhiro Mori
  • Patent number: 6392908
    Abstract: In a driving apparatus of a power semiconductor element for conducting or interrupting a main current, first resistance variable for changing a first resistance according to a control voltage, and second resistance variable for changing a second resistance according to a voltage between a first and a second terminal are provided, and either one of a voltage of a control power supply or a voltage between the first and the second terminal is voltage-divided by the first resistance and the second resistance, and the divided voltage is applied to a control gate terminal at the time of conducting or interrupting the main current.
    Type: Grant
    Filed: June 21, 2001
    Date of Patent: May 21, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Hideki Miyazaki, Katsunori Suzuki, Koji Tateno, Junichi Sakano, Masahiro Iwamura, Mutsuhiro Mori
  • Patent number: 6373731
    Abstract: A power inverter using a voltage driven switching element, capable of suppressing an excessive surge voltage which is generated on high-speed switching of IGBTs or MOSFETs, and suppressing radio frequency oscillation after the suppression of the surge voltage. The power inverter includes a switching element rendering a power path conducting and non-conducting, and a speeding-up circuit of a feedback path in an active clamping circuit added to the switching element.
    Type: Grant
    Filed: September 1, 2000
    Date of Patent: April 16, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Masahiro Iwamura, Hideki Miyazaki, Katsunori Suzuki, Junichi Sakano, Mutsuhiro Mori, Koji Tateno
  • Publication number: 20020040709
    Abstract: A circuit for supplying an oscillation suppress current is provided between a collector terminal and gate electrode of a main IGBT. The current supply circuit comprises a resistor and a diode which are connected in series. A bypass MOSFET is connected between the series connection and the emitter terminal. No semiconductor element having different temperature characteristics is provided in the current supply circuit.
    Type: Application
    Filed: February 23, 2001
    Publication date: April 11, 2002
    Inventors: Yasuhiko Kohno, Junpei Uruno, Mutsuhiro Mori
  • Publication number: 20020027253
    Abstract: A circuit incorporated IGBT is provided with a semiconductor substrate having an IGBT area and a circuit area which are adjacent to each other. In a semiconductor layer of one conductivity type in which a circuit element is formed in the circuit area, there is provided another semiconductor layer of another conductivity type which adjoins the circuit element and has an impurity concentration higher than that of the semiconductor layer of the one conductivity type. An electrode contacts the other semiconductor layer and is connected to an electrode of the IGBT. Carriers are ejected from the other semiconductor layer to the electrode of the IGBT, thereby making it possible to prevent an erroneous operation of the circuit.
    Type: Application
    Filed: November 7, 2001
    Publication date: March 7, 2002
    Inventors: Yasuhiko Kohno, Mutsuhiro Mori, Junpei Uruno
  • Patent number: 6353258
    Abstract: A semiconductor module has a plurality of power semiconductor devices mounted on a substrate, and a metal foil for wiring is mounted on the substrate so that an asymmetric unit arrangement of the semiconductor devices is formed. In the device, all of the units are arranged in the same direction on the substrate, and all of the units are electrically connected with electrode terminal feet, and the electrode terminal feet are electrically connected with linkage terminal foot. The electrode terminal feet are disposed with a certain interval.
    Type: Grant
    Filed: June 26, 2000
    Date of Patent: March 5, 2002
    Assignees: Hitachi, Ltd., Hitachi Car Engineering Co., Ltd.
    Inventors: Hirokazu Inoue, Ryuichi Saito, Mutsuhiro Mori, Yasutoshi Kurihara, Jin Onuki, Shin Kimura, Satoshi Shimada, Kazuhiro Suzuki, Yukio Kamita, Isao Kobayashi, Kazuji Yamada, Naohiro Momma
  • Publication number: 20010030880
    Abstract: In a driving apparatus of a power semiconductor element for conducting or interrupting a main current, first resistance variable for changing a first resistance according to a control voltage, and second resistance variable for changing a second resistance according to a voltage between a first and a second terminal are provided, and either one of a voltage of a control power supply or a voltage between the first and the second terminal is voltage-divided by the first resistance and the second resistance, and the divided voltage is applied to a control gate terminal at the time of conducting or interrupting the main current.
    Type: Application
    Filed: June 21, 2001
    Publication date: October 18, 2001
    Inventors: Hideki Miyazaki, Katsunori Suzuki, Koji Tateno, Junichi Sakano, Masahiro Iwamura, Mutsuhiro Mori
  • Patent number: 6304472
    Abstract: In order to detect a current with high accuracy in an electric power converting system, an inductor is connected to a main terminal of a switching element in series, and a voltage generated in both ends of the inductor during switching period is integrated using an integrating circuit to detect the current.
    Type: Grant
    Filed: May 12, 2000
    Date of Patent: October 16, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Masahiro Nagasu, Shin Kimura, Mutsuhiro Mori, Kiyoshi Nakata, Mutsuhiro Terunuma
  • Patent number: 6275399
    Abstract: In a driving apparatus of a power semiconductor element for conducting or interrupting a main current, first resistance variable for changing a first resistance according to a control voltage, and second resistance variable for changing a second resistance according to a voltage between a first and a second terminal are provided, and either one of a voltage of a control power supply or a voltage between the first and the second terminal is voltage-divided by the first resistance and the second resistance, and the divided voltage is applied to a control gate terminal at the time of conducting or interrupting the main current.
    Type: Grant
    Filed: September 5, 2000
    Date of Patent: August 14, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Hideki Miyazaki, Katsunori Suzuki, Koji Tateno, Junichi Sakano, Masahiro Iwamura, Mutsuhiro Mori
  • Publication number: 20010005031
    Abstract: In a semiconductor device having a first terminal 101 (source terminal) and a second terminal 102 (drain terminal), the substrate main surface of a semiconductor chip is on the (110) face, the main contact face of an n-type region 2 and a p-type region 4 is the {111} face perpendicular to the (110) face, elongated n-type regions 2 and elongated p-type regions 4 which are arranged alternately and adjacently form a voltage holding area, said first terminal 101 is connected to said p-type regions through wiring, and said second terminal 102 is connected to said n-type regions 2. Also, said p-type region is formed to cover the bottom corners of a gate polycrystalline silicon layer 8.
    Type: Application
    Filed: December 11, 2000
    Publication date: June 28, 2001
    Inventors: Kozo Sakamoto, Yosuke Inoue, Akihiro Miyauchi, Masaki Shiraishi, Mutsuhiro Mori, Atsuo Watanabe, Takasumi Ohyanagi
  • Patent number: 6204717
    Abstract: A semiconductor circuit or a semiconductor device has the current-voltage characteristic that, in a blocking-state of the semiconductor circuit or the semiconductor device, a current gently flows for values of a voltage equal to or greater than a first voltage value but equal to or smaller than a second voltage, whereas a current abruptly flows for values of a voltage greater than the second voltage value. Due to the current-voltage characteristic, energy accumulated in an inductance provided within the circuit is consumed by a differential resistance of the semiconductor circuit or a semiconductor, thereby prevent the occurrence of the electromagnetic noise and the excessively large voltage.
    Type: Grant
    Filed: May 21, 1996
    Date of Patent: March 20, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Masahiro Nagasu, Hideo Kobayashi, Hideki Miyazaki, Shin Kimura, Junichi Sakano, Mutsuhiro Mori
  • Patent number: 6198126
    Abstract: A high voltage semiconductor device is provided with a p layer which forms a main pn-junction, a plurality of p layers which surround the p layer in a ring form, a ring-like n+ layer which further surrounds those p layers, forward field plates extending in the peripheral direction and reverse field plates extending in the inside direction, the field plates being in contact at a low resistance with the p and n+ layers and reaching the surface of an n− layer through an insulating film, the area of the field plates being not less than one half of the n− surface. This arrangement is particularly effective in stabilizing the blocking voltage of a high voltage semiconductor device which is used in a severe environment, and is very effective in improving the reliability of a high voltage control unit.
    Type: Grant
    Filed: November 12, 1998
    Date of Patent: March 6, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Mutsuhiro Mori, Yasumichi Yasuda, Hiromi Hosoya
  • Patent number: 6180966
    Abstract: A trench gate type semiconductor device with a current sensing cell is composed so that the orientation of crystal face at side walls of trenches forming channels of trench gates in a main cell is equal or almost equal, or equivalent or almost equivalent to the orientation of crystal face at side walls of trenches forming channels of trench gates in a current sensing cell, which brings the same performance to the main and sense cells, whereby the high accuracy current sensing can be realized.
    Type: Grant
    Filed: March 25, 1998
    Date of Patent: January 30, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Yasuhiko Kohno, Naoki Sakurai, Mutsuhiro Mori
  • Patent number: 6144046
    Abstract: An inverter apparatus constituted by one or more series connections of plural semiconductor devices each having a pair consisting of an insulated gate bipolar transistor, and a diode, both of which are in a reverse parallel connection with each other, wherein the resistivity of the base layer of the lowest impurity concentration in the diode is lower than that of the base layer of the lowest impurity concentration in the insulated gate bipolar transistor, and wherein a breakdown voltage of said insulated gate bipolar transistor at the time of switching from a conduction state to a blocking state is lower than a breakdown voltage of said insulated gate bipolar transistor and said diode at the time of the blocking state.
    Type: Grant
    Filed: July 29, 1997
    Date of Patent: November 7, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Koumei Hanaoka, Naoki Sakurai, Mutsuhiro Mori
  • Patent number: 5929519
    Abstract: An inverter device includes plural modules, each module being formed by a series circuit having a parallel circuit of a switching device and a first diode, and a parallel circuit of a second switching device and a second diode, allowing a reduced size, high reliability, high frequency switching and low noise. Each of the semiconductor modules includes a plurality of switching device chips and at least one diode chip formed on a metal substrate. Electrode plates are provided in locations of the module adjacent to the switching device chips and the diode chips to facilitate connection of the electrodes of the respective chips to one another and to the outside of the module.
    Type: Grant
    Filed: November 26, 1997
    Date of Patent: July 27, 1999
    Assignee: Hitchi, Ltd.
    Inventors: Mutsuhiro Mori, Ryuichi Saito, Shin Kimura, Syuuji Saitoo, Kiyoshi Nakata, Akira Horie, Yoshihiko Koike, Shigeki Sekine
  • Patent number: 5898199
    Abstract: A high voltage semiconductor device is provided with a p layer which forms a main pn-junction, a plurality of p layers which surround the p layer in a ring form, a ring-like n+ layer which further surrounds those p layers, forward field plates extending in the peripheral direction and reverse field plates extending in the inside direction, the field plates being in contact at a low resistance with the p and n+ layers and reaching the surface of an n- layer through an insulating film, the area of the field plates being not less than one half of the n- surface. This arrangement is particularly effective in stabilizing the blocking voltage of a high voltage semiconductor device which is used in a severe environment, and is very effective in improving the reliability of a high voltage control unit.
    Type: Grant
    Filed: July 15, 1997
    Date of Patent: April 27, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Mutsuhiro Mori, Yasumichi Yasuda, Hiromi Hosoya
  • Patent number: 5859446
    Abstract: In a diode, the backward length L of an anode electrode in a region, where a semiconductor layer of a p.sup.+ conductivity type and an anode electrode do not contact each other, is made longer than the diffusion length of holes in a semiconductor layer of an n.sup.- conductivity type for obtaining a large critical di/dt.
    Type: Grant
    Filed: February 19, 1997
    Date of Patent: January 12, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Masahiro Nagasu, Mutsuhiro Mori, Hideo Kobayashi, Junichi Sakano
  • Patent number: 5804868
    Abstract: A highly reliable semiconductor device having a planar junction, which comprises a main junction and a plurality of field limiting ring regions surrounding the main junction, and an electrically floating conductive layer to completely cover that part of the surface of an n.sup.- layer between the main junction and the nearest field limiting ring region thereto through an insulating layer to suppress influences by external factors such as charged particles, etc. In accordance with such a structured device, when a voltage for making the main junction into a reverse bias state is applied, the potential of the conductive layer becomes fixed to an intermediate potential between the main junction and the nearest field limiting ring region thereto and plays a role of shield effect. In fact, even if the device is incorporated into a resin-sealed package and subjected to reliability tests (high temperature DC reverse bias tests), the breakdown voltage is not changed at all.
    Type: Grant
    Filed: February 13, 1996
    Date of Patent: September 8, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Hideo Kobayashi, Mutsuhiro Mori, Yasumichi Yasuda, Yasunori Nakano
  • Patent number: 5801936
    Abstract: An inverter device includes plural modules, each module being formed by a series circuit having a parallel circuit of a first switching device and a first diode, and a parallel circuit of a second switching device and a second diode, allowing a reduced size, high reliability, high frequency switching and low noise.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: September 1, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Mutsuhiro Mori, Ryuichi Saito, Shin Kimura, Kiyoshi Nakata, Syuuji Saitoo, Akira Horie, Yoshihiko Koike, Shigeki Sekine