Patents by Inventor Akio Sugi

Akio Sugi 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: 9577087
    Abstract: A semiconductor apparatus that has a first parallel pn-layer formed between an active region and an n+-drain region. A peripheral region is provided with a second parallel pn-layer, which has a repetition pitch narrower than the repetition pitch of the first parallel pn-layer. An n?-surface region is formed between the second parallel pn-layer and a first main surface. On the first main surface side of the n?-surface region, a plurality of p-guard ring regions are formed to be separated from each other. A field plate electrode is connected electrically to the outermost p-guard ring region among the p-guard ring regions. A channel stopper electrode is connected electrically to an outermost peripheral p-region of the peripheral region.
    Type: Grant
    Filed: December 7, 2011
    Date of Patent: February 21, 2017
    Assignee: FUI ELECTRIC CO., LTD.
    Inventors: Yasuhiko Onishi, Akio Sugi
  • Patent number: 9087893
    Abstract: A parallel p-n layer (20) is provided as a drift layer between an active portion and an n+ drain region (11). The parallel p-n layer (20) is formed by an n-type region (1) and a p-type region (2) being repeatedly alternately joined. An n-type high concentration region (21) is provided on a first main surface side of the n-type region (1). The n-type high concentration region (21) has an impurity concentration higher than that of an n-type low concentration region (22) provided on a second main surface side of the n-type region (1). The n-type high concentration region (21) has an impurity concentration 1.2 times or more, 3 times or less, preferably 1.5 times or more, 2.5 times or less, greater than that of the n-type low concentration region (22). Also, the n-type high concentration region (21) has one-third or less, preferably one-eighth or more, one-fourth or less, of the thickness of a region of the n-type region (1) adjacent to the p-type region (2).
    Type: Grant
    Filed: January 28, 2011
    Date of Patent: July 21, 2015
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Yasuhiko Onishi, Mutsumi Kitamura, Akio Sugi, Manabu Takei
  • Patent number: 8378418
    Abstract: A bidirectional Trench Lateral Power MOSFET (TLPM) can achieve a high breakdown voltage and a low on-resistance. A plurality of straight-shaped islands having circular portions at both ends are surrounded by a trench arrangement. The islands provide first n source regions and a second n source region is formed on the outside of the islands. With such a pattern, the breakdown voltage in the case where the first n source regions are at a high potential can be higher than the breakdown voltage in the case where the second n source region is at a high potential. Alternatively, in the case of not changing the breakdown voltage, the on-resistance can be reduced.
    Type: Grant
    Filed: August 26, 2010
    Date of Patent: February 19, 2013
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Mutsumi Kitamura, Akio Sugi, Naoto Fujishima, Shinichiro Matsunaga
  • Publication number: 20130026560
    Abstract: A parallel p-n layer (20) is provided as a drift layer between an active portion and an n+ drain region (11). The parallel p-n layer (20) is formed by an n-type region (1) and a p-type region (2) being repeatedly alternately joined. An n-type high concentration region (21) is provided on a first main surface side of the n-type region (1). The n-type high concentration region (21) has an impurity concentration higher than that of an n-type low concentration region (22) provided on a second main surface side of the n-type region (1). The n-type high concentration region (21) has an impurity concentration 1.2 times or more, 3 times or less, preferably 1.5 times or more, 2.5 times or less, greater than that of the n-type low concentration region (22). Also, the n-type high concentration region (21) has one-third or less, preferably one-eighth or more, one-fourth or less, of the thickness of a region of the n-type region (1) adjacent to the p-type region (2).
    Type: Application
    Filed: January 28, 2011
    Publication date: January 31, 2013
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventors: Yasuhiko Onishi, Mutsumi Kitamura, Akio Sugi, Manabu Takei
  • Publication number: 20120228634
    Abstract: A combined semiconductor device performs low conduction loss and low recovery loss characteristics suited to a circuit technology in a soft switching mode at a low cost. The device has a SJ-MOSFET and a wide band gap Schottky barrier diode connected in parallel to a built-in body diode in the SJ-MOSFET. The device includes a MOS type semiconductor element having a superjunction structure and a wide band gap Schottky barrier diode antiparallel-connected to the MOS type semiconductor element. The MOS type semiconductor element has a resistance section series-connected to a built-in body diode in the element. A resistance value of the resistance section is such a value that the forward voltage drop of the built-in body diode in the MOS type semiconductor element is higher than the forward voltage drop of the wide band gap Schottky barrier diode at a rated current of the MOS type semiconductor element.
    Type: Application
    Filed: March 1, 2012
    Publication date: September 13, 2012
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventors: Akio SUGI, Tatsuhiko Fujihira
  • Publication number: 20120126315
    Abstract: A semiconductor apparatus that has a first parallel pn-layer formed between an active region and an n+-drain region. A peripheral region is provided with a second parallel pn-layer, which has a repetition pitch narrower than the repetition pitch of the first parallel pn-layer. An n?-surface region is formed between the second parallel pn-layer and a first main surface. On the first main surface side of the n?-surface region, a plurality of p-guard ring regions are formed to be separated from each other. A field plate electrode is connected electrically to the outermost p-guard ring region among the p-guard ring regions. A channel stopper electrode is connected electrically to an outermost peripheral p-region of the peripheral region.
    Type: Application
    Filed: December 7, 2011
    Publication date: May 24, 2012
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventors: Yasuhiko ONISHI, Akio Sugi
  • Patent number: 8138542
    Abstract: A semiconductor device including an n-type semiconductor substrate, a p-type channel region and a junction layer provided between the n-type semiconductor substrate and the p-type channel region is disclosed. The junction layer has n-type drift regions and p-type partition regions alternately arranged in the direction in parallel with the principal surface of the n-type semiconductor substrate. The p-type partition region forming the junction layer is made to have a higher impurity concentration than the n-type drift region. This enables the semiconductor device to have an enhanced breakdown voltage and, at the same time, have a reduced on-resistance.
    Type: Grant
    Filed: April 21, 2009
    Date of Patent: March 20, 2012
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Koh Yoshikawa, Akio Sugi, Kouta Takahashi, Manabu Takei, Haruo Nakazawa, Noriyuki Iwamuro
  • Patent number: 7898024
    Abstract: In a MIS-type semiconductor device having a trench gate structure, a withstand voltage is ensured without changing the thickness of a drift layer and on-resistance can be reduced without applying a high gate drive voltage. The lower half of a trench extending through a p-base region into an n-drift region is filled with a high-permittivity dielectric having a relative permittivity that is higher than that of a silicon oxide film, preferably a silicon nitride film, and an insulated gate structure including a gate insulator and a gate electrode is fabricated on the high-permittivity dielectric. The depth d2 of the deepest portion of the high-permittivity dielectric is designed to be deeper than the depth d1 of a depletion layer in the semiconductor region away from the high-permittivity dielectric.
    Type: Grant
    Filed: January 31, 2008
    Date of Patent: March 1, 2011
    Assignee: Fuji Electric Systems Co., Ltd.
    Inventors: Akio Sugi, Tatsuji Nagaoka, Hong-fei Lu
  • Publication number: 20100330398
    Abstract: A bidirectional Trench Lateral Power MOSFET (TLPM) can achieve a high breakdown voltage and a low on-resistance. A plurality of straight-shaped islands having circular portions at both ends are surrounded by a trench arrangement. The islands provide first n source regions and a second n source region is formed on the outside of the islands. With such a pattern, the breakdown voltage in the case where the first n source regions are at a high potential can be higher than the breakdown voltage in the case where the second n source region is at a high potential. Alternatively, in the case of not changing the breakdown voltage, the on-resistance can be reduced.
    Type: Application
    Filed: August 26, 2010
    Publication date: December 30, 2010
    Applicant: Fuji Electric Systems Co., Ltd.
    Inventors: Mutsumi Kitamura, Akio Sugi, Naoto Fujishima, Shinichiro Matsunaga
  • Patent number: 7800167
    Abstract: A bidirectional Trench Lateral Power MOSFET (TLPM) can achieve a high breakdown voltage and a low on-resistance. A plurality of straight-shaped islands having circular portions at both ends are surrounded by a trench arrangement. The islands provide first n source regions and a second n source region is formed on the outside of the islands. With such a pattern, the breakdown voltage in the case where the first n source regions are at a high potential can be higher than the breakdown voltage in the case where the second n source region is at a high potential. Alternatively, in the case of not changing the breakdown voltage, the on-resistance can be reduced.
    Type: Grant
    Filed: May 25, 2007
    Date of Patent: September 21, 2010
    Assignee: Fuji Electric Systems Co., Ltd.
    Inventors: Mutsumi Kitamura, Akio Sugi, Naoto Fujishima, Shinichiro Matsunaga
  • Publication number: 20090206398
    Abstract: A semiconductor device including an n-type semiconductor substrate, a p-type channel region and a junction layer provided between the n-type semiconductor substrate and the p-type channel region is disclosed. The junction layer has n-type drift regions and p-type partition regions alternately arranged in the direction in parallel with the principal surface of the n-type semiconductor substrate. The p-type partition region forming the junction layer is made to have a higher impurity concentration than the n-type drift region. This enables the semiconductor device to have an enhanced breakdown voltage and, at the same time, have a reduced on-resistance.
    Type: Application
    Filed: April 21, 2009
    Publication date: August 20, 2009
    Applicant: FUJI ELECTRIC HOLDINGS CO., LTD.
    Inventors: Koh YOSHIKAWA, Akio SUGI, Kouta TAKAHASHI, Manabu TAKEI, Haruo NAKAZAWA, Noriyuki IWAMURO
  • Patent number: 7535059
    Abstract: A semiconductor device including an n-type semiconductor substrate, a p-type channel region and a junction layer provided between the n-type semiconductor substrate and the p-type channel region is disclosed. The junction layer has n-type drift regions and p-type partition regions alternately arranged in the direction in parallel with the principal surface of the n-type semiconductor substrate. The p-type partition region forming the junction layer is made to have a higher impurity concentration than the n-type drift region. This enables the semiconductor device to have an enhanced breakdown voltage and, at the same time, have a reduced on-resistance.
    Type: Grant
    Filed: November 28, 2006
    Date of Patent: May 19, 2009
    Assignee: Fuji Electric Holdings Co., Ltd.
    Inventors: Koh Yoshikawa, Akio Sugi, Kouta Takahashi, Manabu Takei, Haruo Nakazawa, Noriyuki Iwamuro
  • Publication number: 20080303087
    Abstract: Gate electrodes of a TLPM and gate electrodes of planar devices are formed by patterning a same polysilicon layer. Drain electrode(s) and source electrode(s) of the TLPM and drain electrodes and source electrodes of the planar devices are formed by patterning a same metal layer. Therefore, the TLPM and the planar devices can be connected electrically to each other by resulting metal wiring layers and polysilicon layers without the need for performing wire bonding on a printed circuit board.
    Type: Application
    Filed: April 24, 2008
    Publication date: December 11, 2008
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventors: Akio Sugi, Naoto Fujishima, Mutsumi Kitamura, Katsuya Tabuchi, Setsuko Wakimoto
  • Publication number: 20080258211
    Abstract: In a MIS-type semiconductor device having a trench gate structure, a withstand voltage is ensured without changing the thickness of a drift layer and on-resistance can be reduced without applying a high gate drive voltage. The lower half of a trench extending through a p-base region into an n-drift region is filled with a high-permittivity dielectric having a relative permittivity that is higher than that of a silicon oxide film, preferably a silicon nitride film, and an insulated gate structure including a gate insulator and a gate electrode is fabricated on the high-permittivity dielectric. The depth d2 of the deepest portion of the high-permittivity dielectric is designed to be deeper than the depth d1 of a depletion layer in the semiconductor region away from the high-permittivity dielectric.
    Type: Application
    Filed: January 31, 2008
    Publication date: October 23, 2008
    Applicant: FUJI ELECTRIC HOLDINGS CO., LTD.
    Inventors: Akio SUGI, Tatsuji NAGAOKA, Hong-fei LU
  • Patent number: 7365392
    Abstract: Gate electrodes of a TLPM and gate electrodes of planar devices are formed by patterning a same polysilicon layer. Drain electrode(s) and source electrode(s) of the TLPM and drain electrodes and source electrodes of the planar devices are formed by patterning a same metal layer. Therefore, the TLPM and the planar devices can be connected electrically to each other by resulting metal wiring layers and polysilicon layers without the need for performing wire bonding on a printed circuit board.
    Type: Grant
    Filed: December 14, 2004
    Date of Patent: April 29, 2008
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Akio Sugi, Naoto Fujishima, Mutsumi Kitamura, Katsuya Tabuchi, Setsuko Wakimoto
  • Publication number: 20070274110
    Abstract: A bidirectional Trench Lateral Power MOSFET (TLPM) can achieve a high breakdown voltage and a low on-resistance. A plurality of straight-shaped islands having circular portions at both ends are surrounded by a trench arrangement. The islands provide first n source regions and a second n source region is formed on the outside of the islands. With such a pattern, the breakdown voltage in the case where the first n source regions are at a high potential can be higher than the breakdown voltage in the case where the second n source region is at a high potential. Alternatively, in the case of not changing the breakdown voltage, the on-resistance can be reduced.
    Type: Application
    Filed: May 25, 2007
    Publication date: November 29, 2007
    Applicant: Fuji Electric Device Technology Co., Ltd
    Inventors: Mutsumi Kitamura, Akio Sugi, Naoto Fujishima, Shinichiro Matsunaga
  • Patent number: 7256086
    Abstract: A semiconductor device is provided that can be manufactured by a simpler process than a conventional lateral trench power MOSFET for use with an 80V breakdown voltage, and which has a lower device pitch and lower on-state resistance per unit area than a conventional lateral power MOSFET for use with a lower breakdown voltage than 80V. A gate oxide film is formed thinly along the lateral surfaces of a trench at a uniform thickness. Then, a gate oxide film is formed along the bottom surface of the trench by selective oxidation so as to be thicker than the gate oxide film on the lateral surfaces of the trench and so as to become progressively thicker from the edge of the bottom surface of the trench toward drain polysilicon.
    Type: Grant
    Filed: January 10, 2006
    Date of Patent: August 14, 2007
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Katsuya Tabuchi, Naoto Fujishima, Mutsumi Kitamura, Akio Sugi
  • Publication number: 20070158740
    Abstract: A semiconductor device including an n-type semiconductor substrate, a p-type channel region and a junction layer provided between the n-type semiconductor substrate and the p-type channel region is disclosed. The junction layer has n-type drift regions and p-type partition regions alternately arranged in the direction in parallel with the principal surface of the n-type semiconductor substrate. The p-type partition region forming the junction layer is made to have a higher impurity concentration than the n-type drift region. This enables the semiconductor device to have an enhanced breakdown voltage and, at the same time, have a reduced on-resistance.
    Type: Application
    Filed: November 28, 2006
    Publication date: July 12, 2007
    Applicant: FUJI ELECTRIC HOLDINGS CO., LTD.
    Inventors: Koh Yoshikawa, Akio Sugi, Kouta Takahashi, Manabu Takei, Haruo Nakazawa, Noriyuki Iwamuro
  • Patent number: 7109551
    Abstract: A semiconductor structure with device trench and a semiconductor device in the device trench, that enables realization of high integration, lowered on-resistance, reduction in switching losses and a high operation speed in a semiconductor device provided with a lateral IGBT, and that prevents malfunctions such as latchup when IGBTs or an IGBT and CMOS devices are integrated together. The structure includes an SOI substrate having a supporting substrate, an oxide film and a p?-semiconductor layer. An island-like element-forming region is isolated by a trench isolation region from surroundings. The trench isolation region includes an isolation trench with an insulation film on its inner wall. The device trench is formed in the element-forming region. A gate electrode is formed with a gate insulator film in the device trench. A collector region and an emitter region outside are provided respectively on the bottom and the outside of the device trench.
    Type: Grant
    Filed: August 27, 2004
    Date of Patent: September 19, 2006
    Assignee: Fuji Electric Holdings Co., Ltd.
    Inventors: Akio Sugi, Naoto Fujishima
  • Publication number: 20060110875
    Abstract: A semiconductor device is provided that can be manufactured by a simpler process than a conventional lateral trench power MOSFET for use with an 80V breakdown voltage, and which has a lower device pitch and lower on-state resistance per unit area than a conventional lateral power MOSFET for use with a lower breakdown voltage than 80V. A gate oxide film is formed thinly along the lateral surfaces of a trench at a uniform thickness. Then, a gate oxide film is formed along the bottom surface of the trench by selective oxidation so as to be thicker than the gate oxide film on the lateral surfaces of the trench and so as to become progressively thicker from the edge of the bottom surface of the trench toward drain polysilicon.
    Type: Application
    Filed: January 10, 2006
    Publication date: May 25, 2006
    Applicant: Fuji Electric Co., Ltd.
    Inventors: Katsuya Tabuchi, Naoto Fujishima, Mutsumi Kitamura, Akio Sugi