Patents by Inventor Yasuhiko Onishi

Yasuhiko Onishi 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: 20140061644
    Abstract: An SJ-MOSFET can include an active region serving as a main current path and a temperature detection region including a temperature detecting diode. Main SJ cells in which n drift regions and p partition regions are alternately adjacent to each other are arranged in a drift layer in the active region. The temperature detection region is provided in the active region. Fine SJ cells in which n drift regions and p partition regions are alternately bonded to each other at a pitch less than that of the n drift region and the p partition region of the main SJ cell are arranged in the drift layer in the temperature detection region. The temperature detecting diode is formed above the fine SJ cells with an insulating film) interposed therebetween. The temperature detecting diode includes a p+ anode region and an n+ cathode region.
    Type: Application
    Filed: November 13, 2013
    Publication date: March 6, 2014
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventors: Dawei CAO, Yasuhiko ONISHI
  • Publication number: 20140035002
    Abstract: Semiconductor regions are alternately arranged in a parallel pn layer in which an n-type region and a p-type region are alternately arranged parallel to the main surface of a semiconductor substrate. Pitch between n drift region and p partition region of a second parallel pn layer in an edge termination region is two thirds of pitch between n drift region and p partition region of a first parallel pn layer in an active region. At boundaries between main SJ cells and fine SJ cells at four corners of the semiconductor substrate having rectangular shape in plan view, ends of two pitches of main SJ cells face the ends of three pitches of fine SJ cells. In this way, it is possible to reduce the influence of a process variation and thus reduce mutual diffusion between n drift region and p partition region of the fine SJ cell.
    Type: Application
    Filed: October 15, 2013
    Publication date: February 6, 2014
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventors: Dawei CAO, Mutsumi KITAMURA, Takahiro TAMURA, Yasuhiko ONISHI
  • Patent number: 8432013
    Abstract: A semiconductor device is provided with a peripheral region that has a narrow width and exhibits good electric field relaxation and high robustness against induced charges. The device has an active region for main current flow and a peripheral region surrounding the active region on a principal surface of a semiconductor substrate of a first conductivity type. The peripheral region has a guard ring of a second conductivity type composed of straight sections and curved sections connecting the straight sections formed in a region of the principal surface surrounding the active region, and a pair of polysilicon field plates in a ring shape formed separately on inner and outer circumferential sides of the guard ring. The surface of the guard ring and the pair of polysilicon field plates of the inner circumferential side and the outer circumferential side are electrically connected with a metal film in the curved section.
    Type: Grant
    Filed: February 2, 2011
    Date of Patent: April 30, 2013
    Assignee: Fuji Electric Co., Ltd.
    Inventor: Yasuhiko Onishi
  • 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: 20120211833
    Abstract: A super-junction semiconductor device includes a drift layer including an alternating-conductivity-type layer that includes n-type region and p-type region arranged alternately in parallel to the first major surface of an n-type substrate. These alternating regions extend deep in a direction perpendicular to the first major surface. The first major surface includes a main device region with a gate electrode and a main source electrode and sensing device region with a gate electrode and a sensing source electrode. There is a common drain electrode on the second major surface of the substrate. There is a separation region between the main device region and the sensing device region. It includes an n-type region and p-type regions in the n-type region. The p-type regions are in an electrically floating state in the directions parallel and perpendicular to the first alternating-conductivity-type layer.
    Type: Application
    Filed: February 9, 2012
    Publication date: August 23, 2012
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventors: Takahiro TAMURA, Yasuhiko ONISHI
  • 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
  • Publication number: 20120112306
    Abstract: A superjunction semiconductor device is disclosed which has, in the active section, a first alternating-conductivity-type layer which makes a current flow in the ON-state of the device and sustains a bias voltage in the OFF-state of the device. There is a second alternating-conductivity-type layer in a edge-termination section surrounding the active section. The width of a region of a second conductivity type in the second alternating-conductivity-type layer becomes narrower at a predetermined rate from the edge on the active section side toward the edge of the edge termination section. The superjunction semiconductor device facilitates manufacturing the edge-termination section which exhibits a high breakdown voltage and a high reliability for breakdown voltage through a process that exhibits a high mass-productivity.
    Type: Application
    Filed: November 7, 2011
    Publication date: May 10, 2012
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventor: Yasuhiko ONISHI
  • Publication number: 20120098064
    Abstract: A semiconductor device is disclosed wherein a peripheral region with a high breakdown voltage and high robustness against induced surface charge is manufactured using a process with high mass productivity. The device has n-type drift region and p-type partition region of layer-shape deposited in a vertical direction to one main surface of n-type semiconductor substrate with high impurity concentration form as drift layer, alternately adjacent parallel pn layers in a direction along one main surface. Active region through which current flows and peripheral region enclosing the active region include parallel pn layers.
    Type: Application
    Filed: October 14, 2011
    Publication date: April 26, 2012
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventor: Yasuhiko ONISHI
  • Publication number: 20110204469
    Abstract: A semiconductor device is provided with a peripheral region that has a narrow width and exhibits good electric field relaxation and high robustness against induced charges. The device has an active region for main current flow and a peripheral region surrounding the active region on a principal surface of a semiconductor substrate of a first conductivity type. The peripheral region has a guard ring of a second conductivity type composed of straight sections and curved sections connecting the straight sections formed in a region of the principal surface surrounding the active region, and a pair of polysilicon field plates in a ring shape formed separately on inner and outer circumferential sides of the guard ring. The surface of the guard ring and the pair of polysilicon field plates of the inner circumferential side and the outer circumferential side are electrically connected with a metal film in the curved section.
    Type: Application
    Filed: February 2, 2011
    Publication date: August 25, 2011
    Applicant: C/O FUJI ELECTRIC SYSTEMS CO., LTD.
    Inventor: Yasuhiko ONISHI
  • Patent number: 7911020
    Abstract: A semiconductor device has an active portion having at least one well region in a semiconductor layer, and a breakdown voltage maintaining structure surrounding the active portion. The maintaining structure includes a conductor layer over each of a plurality of guard rings with an insulating film interposed in between and connected to the respective guard ring. An inner side end portion of each conductor layer projects over the immediate adjacent inner side guard ring. The impurity concentration of the guard rings is set between the impurity concentrations of the semiconductor layer and the well regions. A field plate can extend over the innermost conductor layer with the insulating film interposed in between. The field plate is in contact with the outermost well region and is in contact with the first conductor layer. The outer side end of the field plate extends outwardly beyond an outer side end of the innermost conductor layer.
    Type: Grant
    Filed: July 10, 2008
    Date of Patent: March 22, 2011
    Assignee: Fuji Electric Systems Co., Ltd.
    Inventors: Yasushi Niimura, Takashi Kobayashi, Masanori Inoue, Yasuhiko Onishi
  • Publication number: 20090215167
    Abstract: A cationic graft-copolymer for a non-viral gene delivery vector comprising a unit derived from a cationic derivative of a water-soluble linear polymers having a hydroxyl groups, namely, a cationic polysaccharide of the following formula (1) and the cationic derivative of polyvinylalcohol of the following formula (2) or the cationic derivative of the partial hydrolyzed polyvinylalcohol of the following formula (3) and a unit derived from a polymerizable olefin compound of the following formula (4) a process for preparing the same and a transfection reagent made therefrom.
    Type: Application
    Filed: December 10, 2008
    Publication date: August 27, 2009
    Inventor: Yasuhiko Onishi
  • Publication number: 20090045481
    Abstract: A semiconductor device has an active portion having at least one well region in a semiconductor layer, and a breakdown voltage maintaining structure surrounding the active portion. The maintaining structure includes a conductor layer over each of a plurality of guard rings with an insulating film interposed in between and connected to the respective guard ring. An inner side end portion of each conductor layer projects over the immediate adjacent inner side guard ring. The impurity concentration of the guard rings is set between the impurity concentrations of the semiconductor layer and the well regions. A field plate can extend over the innermost conductor layer with the insulating film interposed in between. The field plate is in contact with the outermost well region and is in contact with the first conductor layer. The outer side end of the field plate extends outwardly beyond an outer side end of the innermost conductor layer.
    Type: Application
    Filed: July 10, 2008
    Publication date: February 19, 2009
    Applicant: FUJI ELECTRIC DEVICE TECHNOLOGY CO., LTD.
    Inventors: Yasushi NIIMURA, Takashi KOBAYASHI, Masanori INOUE, Yasuhiko ONISHI
  • Patent number: 7473733
    Abstract: A cationic graft-copolymer for a non-viral gene delivery vector comprising a unit derived from a cationic derivative of a water-soluble linear polymers having a hydroxyl groups, namely, a cationic polysaccharide of the following formula (1) [C6H7O2(OH)3-a (OX)a]x H2O (1) and the cationic derivative of polyvinylalcohol of the following formula (2) or the cationic derivative of the partial hydrolyzed polyvinylalcohol of the following formula (3) [CH2 CH(OH)1-b (OX)b]n (2) [CH2CH(OH)1-b-c (OX)b (OAc)c]n (3) and a unit derived from a polymerizable olefin compound of the following formula (4) R4R6?-C—C—(4)?R5 R7(a, x, b, n, c, Ac, X, R4, R5, R6, and R7 are defined in claim 1-6); a process for preparing the same and a transfection reagent made therefrom.
    Type: Grant
    Filed: January 8, 2004
    Date of Patent: January 6, 2009
    Inventor: Yasuhiko Onishi
  • Patent number: 7372111
    Abstract: The superjunction semiconductor device includes a drain drift section, which includes a first alternating conductivity type layer formed of first n-type regions and first p-type regions arranged alternately. The device also includes a peripheral section around the drain drift section, which includes a second alternating conductivity type layer formed of second n-type regions and second p-type regions arranged alternately. The peripheral section further includes a third alternating conductivity type layer in its surface portion. The third alternating conductivity type layer is formed of third n-type regions and third p-type regions arranged alternately. At least the peripheral section is configured to improve the avalanche withstanding capability over the entire device.
    Type: Grant
    Filed: August 4, 2005
    Date of Patent: May 13, 2008
    Assignee: Fuji Electric Device Technology Co., Ltd.
    Inventors: Yasuhiko Onishi, Takeyoshi Nishimura, Yasushi Niimura, Masanori Inoue
  • Patent number: 7235841
    Abstract: A semiconductor device includes an active region, an alternating conductivity type layer, and an insulation region surrounding the alternating conductivity type layer provided in a periphery section as a voltage withstanding section. The insulation region is made of an insulator with the critical electric field strength higher than that of the semiconductor and reaches an n+-drain layer on the bottom surface side of the device from a surface on the side on which a surface structure section is formed. In the alternating conductivity type layer, the width of the p-type partition region adjacent to the insulation region is made narrower than the width of the p-type partition region not adjacent to the insulation region to ensure a balanced state of charges at the end of the drift section made up of the alternating conductivity type layer. A high breakdown voltage is ensured with the length of the periphery section shortened.
    Type: Grant
    Filed: October 26, 2004
    Date of Patent: June 26, 2007
    Assignee: Fuji Electric Device Technology Co., Ltd.
    Inventors: Yasuhiko Onishi, Takeyoshi Nishimura, Yasushi Niimura, Hitoshi Abe
  • Patent number: 7042046
    Abstract: Disclosed is a semiconductor device facilitating a peripheral portion thereof with a breakdown voltage higher than the breakdown voltage in the drain drift layer without employing a guard ring or field plate. A preferred embodiment includes a drain drift region with a first alternating conductivity type layer formed of n drift current path regions and p partition regions arranged alternately with each other, and a breakdown withstanding region with a second alternating conductivity type layer formed of n regions and p regions arranged alternately with each other, the breakdown withstanding region providing no current path in the ON-state of the device and being depleted in the OFF-state of the device. Since depletion layers expand in both directions from multiple pn-junctions into n regions and p regions in the OFF-state of the device, the adjacent areas of p-type base regions, the outer area of the semiconductor chip and the deep area of the semiconductor chip are depleted.
    Type: Grant
    Filed: August 25, 2004
    Date of Patent: May 9, 2006
    Assignee: Fuji Electric Device Technology Co., Ltd.
    Inventors: Yasuhiko Onishi, Tatsuhiko Fujihira, Katsunori Ueno, Susumu Iwamoto, Takahiro Sato, Tatsuji Nagaoka
  • Patent number: 7002205
    Abstract: Disclosed is a semiconductor device facilitating a peripheral portion thereof with a breakdown voltage higher than the breakdown voltage in the drain drift layer without employing a guard ring or field plate. A preferred embodiment includes a drain drift region with a first alternating conductivity type layer formed of n drift current path regions and p partition regions arranged alternately with each other, and a breakdown withstanding region with a second alternating conductivity type layer formed of n regions and p regions arranged alternately with each other, the breakdown withstanding region providing no current path in the ON-state of the device and being depleted in the OFF-state of the device. Since depletion layers expand in both directions from multiple pn-junctions into n regions and p regions in the OFF-state of the device, the adjacent areas of p-type base regions, the outer area of the semiconductor chip and the deep area of the semiconductor chip are depleted.
    Type: Grant
    Filed: December 12, 2003
    Date of Patent: February 21, 2006
    Assignee: Fuji Electric Device Technology Co., Ltd.
    Inventors: Yasuhiko Onishi, Tatsuhiko Fujihira, Katsunori Ueno, Susumu Iwamoto, Takahiro Sato, Tatsuji Nagaoka
  • Patent number: 7002211
    Abstract: A lateral semiconductor device includes an alternating conductivity type layer for providing a first semiconductor current path in the ON-state of the device and for being depleted in the OFF-state of the device, that has an improved structure for realizing a high breakdown voltage in the curved sections of the alternating conductivity type layer.
    Type: Grant
    Filed: May 19, 2004
    Date of Patent: February 21, 2006
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Yasuhiko Onishi, Tatsuhiko Fujihira, Susumu Iwamoto, Takahiro Sato
  • Publication number: 20060033153
    Abstract: The superjunction semiconductor device includes a drain drift section, which includes a first alternating conductivity type layer formed of first n-type regions and first p-type regions arranged alternately. The device also includes a peripheral section around the drain drift section, which includes a second alternating conductivity type layer formed of second n-type regions and second p-type regions arranged alternately. The peripheral section further includes a third alternating conductivity type layer in its surface portion. The third alternating conductivity type layer is formed of third n-type regions and third p-type regions arranged alternately. At least the peripheral section is configured to improve the avalanche withstanding capability over the entire device.
    Type: Application
    Filed: August 4, 2005
    Publication date: February 16, 2006
    Applicant: Fuji Electric Device Technology Co., Ltd.
    Inventors: Yasuhiko Onishi, Takeyoshi Nishimura, Yasushi Niimura, Masanori Inoue
  • Publication number: 20050287110
    Abstract: A cationic graft-copolymer for a non-viral gene delivery vector comprising a unit derived from a cationic derivative of a water-soluble linear polymers having a hydroxyl groups, namely, a cationic polysaccharide of the following formula (1) [C6H7O2(OH)3-a (OX)a]xH2O (1) and the cationic derivative of polyvinylalcohol of the following formula (2) or the cationic derivative of the partial hydrolyzed polyvinylalcohol of the following formula (3) [CH2 CH(OH)1-b (OX)b]n (2) [CH2CH(OH)1-b-c (OX)b (OAc)c]n (3) and a unit derived from a polymerizable olefin compound of the following formula (4) R4R6?-C—C— (4)?R5R7(a, x, b, n, c, Ac, X, R4, R5, R6, and R7 are defined in claim 1-6); a process for preparing the same and a transfection reagent made therefrom.
    Type: Application
    Filed: January 8, 2004
    Publication date: December 29, 2005
    Inventor: Yasuhiko Onishi