Patents by Inventor Tsunenobu Kimoto

Tsunenobu Kimoto 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: 7671387
    Abstract: A lateral junction field effect transistor includes a first gate electrode layer arranged in a third semiconductor layer between source/drain region layers, having a lower surface extending on the second semiconductor layer, and doped with p-type impurities more heavily than the second semiconductor layer, and a second gate electrode layer arranged in a fifth semiconductor layer between the source/drain region layers, having a lower surface extending on a fourth semiconductor layer, having substantially the same concentration of p-type impurities as the first gate electrode layer, and having the same potential as the first gate electrode layer. Thereby, the lateral junction field effect transistor has a structure, which can reduce an on-resistance while maintaining good breakdown voltage properties.
    Type: Grant
    Filed: July 24, 2008
    Date of Patent: March 2, 2010
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kazuhiro Fujikawa, Shin Harada, Kenichi Hirotsu, Satoshi Hatsukawa, Takashi Hoshino, Hiroyuki Matsunami, Tsunenobu Kimoto
  • Publication number: 20090315082
    Abstract: A lateral junction field effect transistor includes a first gate electrode layer arranged in a third semiconductor layer between source/drain region layers, having a lower surface extending on the second semiconductor layer, and doped with p-type impurities more heavily than the second semiconductor layer, and a second gate electrode layer arranged in a fifth semiconductor layer between the source/drain region layers, having a lower surface extending on a fourth semiconductor layer, having substantially the same concentration of p-type impurities as the first gate electrode layer, and having the same potential as the first gate electrode layer. Thereby, the lateral junction field effect transistor has a structure, which can reduce an on-resistance while maintaining good breakdown voltage properties.
    Type: Application
    Filed: September 1, 2009
    Publication date: December 24, 2009
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Kazuhiro Fujikawa, Shin Harada, Kenichi Hirotsu, Satoshi Hatsukawa, Takashi Hoshino, Hiroyuki Matsunami, Tsunenobu Kimoto
  • Publication number: 20090261362
    Abstract: 4H—InGaAlN alloy based optoelectronic and electronic devices on non-polar face are formed on 4H—AlN or 4H—AlGaN on (11-20) a-face 4H—SiC substrates. Typically, non polar 4H—AlN is grown on 4H—SiC (11-20) by molecular beam epitaxy (MBE). Subsequently, III-V nitride device layers are grown by metal organic chemical vapor deposition (MOCVD) with 4H-polytype for all of the layers. The non-polar device does not contain any built-in electric field due to the spontaneous and piezoelectric polarization. The optoelectronic devices on the non-polar face exhibits higher emission efficiency with shorter emission wavelength because the electrons and holes are not spatially separated in the quantum well. Vertical device configuration for lasers and light emitting diodes (LEDs) using conductive 4H—AlGaN interlayer on conductive 4H—SiC substrates makes the chip size and series resistance smaller. The elimination of such electric field also improves the performance of high speed and high power transistors.
    Type: Application
    Filed: July 1, 2009
    Publication date: October 22, 2009
    Applicant: PANASONIC CORPORATION
    Inventors: Tetsuzo UEDA, Tsunenobu Kimoto, Hiroyuki Matsunami, Jun Suda, Norio Onojima
  • Patent number: 7528426
    Abstract: A lateral JFET has a basic structure including an n-type semiconductor layer (3) formed of an n-type impurity region and a p-type semiconductor layer formed of a p-type impurity region on the n-type semiconductor layer (3). Moreover, in the p-type semiconductor layer, there are provided a p+-type gate region layer (7) extending into the n-type semiconductor layer (3) and containing p-type impurities of an impurity concentration higher than that of the n-type semiconductor layer (3) and an n+-type drain region layer (9) spaced from the p+-type gate region layer (7) by a predetermined distance and containing n-type impurities of an impurity concentration higher than that of the n-type semiconductor layer (3). With this structure, the lateral JFET can be provided that has an ON resistance further decreased while maintaining a high breakdown voltage performance.
    Type: Grant
    Filed: January 20, 2006
    Date of Patent: May 5, 2009
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Shin Harada, Kenichi Hirotsu, Hiroyuki Matsunami, Tsunenobu Kimoto
  • Publication number: 20090072243
    Abstract: In the present invention, a technology for causing arbitrary polarity, crystal face and crystal orientation to exist mixedly in a plane on the surface of a SiC substrate, and for forming a SiC layer or a group III-nitride or group II-oxide layer on the surface, is provided. A first SiC substrate 41 having (0001) face and a second SiC substrate 44 having (000-1) face are prepared. An oxide film 43 is formed on the surfaces of the SiC substrates 41 and 44 by subjecting them to an oxidation treatment, and then the two SiC substrates are fusion-bonded so that the rear surface of the second SiC substrate and the surface of the first SiC substrate are brought into contact with each other. Subsequently, a part corresponding to the second SiC substrate 44 is made thin (44a). Subsequently, a thin layer 44a of the second SiC substrate is removed in accordance with required periodic reversal to be processed in stripes by using a lithography technology and reactive ion etching technology.
    Type: Application
    Filed: April 5, 2006
    Publication date: March 19, 2009
    Inventors: Jun Suda, Tsunenobu Kimoto
  • Publication number: 20080277696
    Abstract: A lateral junction field effect transistor includes a first gate electrode layer arranged in a third semiconductor layer between source/drain region layers, having a lower surface extending on the second semiconductor layer, and doped with p-type impurities more heavily than the second semiconductor layer, and a second gate electrode layer arranged in a fifth semiconductor layer between the source/drain region layers, having a lower surface extending on a fourth semiconductor layer, having substantially the same concentration of p-type impurities as the first gate electrode layer, and having the same potential as the first gate electrode layer. Thereby, the lateral junction field effect transistor has a structure, which can reduce an on-resistance while maintaining good breakdown voltage properties.
    Type: Application
    Filed: July 24, 2008
    Publication date: November 13, 2008
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Kazuhiro Fujikawa, Shin Harada, Kenichi Hirotsu, Satoshi Hatsukawa, Takashi Hoshino, Hiroyuki Matsunami, Tsunenobu Kimoto
  • Patent number: 7420232
    Abstract: A lateral junction field effect transistor includes a first gate electrode layer arranged in a third semiconductor layer between source/drain region layers, having a lower surface extending on the second semiconductor layer, and doped with p-type impurities more heavily than the second semiconductor layer, and a second gate electrode layer arranged in a fifth semiconductor layer between the source/drain region layers, having a lower surface extending on a fourth semiconductor layer, having substantially the same concentration of p-type impurities as the first gate electrode layer, and having the same potential as the first gate electrode layer. Thereby, the lateral junction field effect transistor has a structure, which can reduce an on-resistance while maintaining good breakdown voltage properties.
    Type: Grant
    Filed: April 11, 2006
    Date of Patent: September 2, 2008
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kazuhiro Fujikawa, Shin Harada, Kenichi Hirotsu, Satoshi Hatsukawa, Takashi Hoshino, Hiroyuki Matsunami, Tsunenobu Kimoto
  • Patent number: 7321142
    Abstract: On an SiC single crystal substrate, an electric field relaxation layer and a p? type buffer layer are formed. The electric field relaxation layer is formed between the p? type buffer layer and the SiC single crystal substrate to contact SiC single crystal substrate. On the p? type buffer layer, an n type semiconductor layer is formed. On the n type semiconductor layer, a p type semiconductor layer is formed. In the p type semiconductor layer, an n+ type source region layer and an n+ type drain region layer are formed separated by a prescribed distance from each other. At a part of the region of p type semiconductor layer between the n+ type source region layer and the n+ type drain region layer, a p+ type gate region layer is formed.
    Type: Grant
    Filed: May 21, 2004
    Date of Patent: January 22, 2008
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kazuhiro Fujikawa, Shin Harada, Hiroyuki Matsunami, Tsunenobu Kimoto
  • Publication number: 20070221119
    Abstract: A method of epitaxial growth of a 4H—SiC single crystal enabling growth of an SiC single crystal with low defects and low impurities able to be used for a semiconductor material at a practical growth rate, comprising growing a 4H—SiC single crystal on a 4H—SiC single crystal substrate by epitaxial growth while inclining an epitaxial growth plane of the substrate from a (0001) plane of the 4H—SiC single crystal by an off-angle of at least 12 degrees and less than 30 degrees in a <11-20> axial direction, and a 4H—SiC single crystal obtained by the same.
    Type: Application
    Filed: May 13, 2005
    Publication date: September 27, 2007
    Applicants: TOYOTA JIDOSHA KABUSHIKI KAISHA, SIXON LTD
    Inventors: Tsunenobu Kimoto, Hiromu Shiomi, Hiroaki Saitoh
  • Patent number: 7241694
    Abstract: A method for manufacturing a silicon carbide semiconductor device includes the steps of: forming a trench mask on an upper surface of a semiconductor substrate; forming the trench such that the trench having an aspect ratio equal to or larger than 2 and having a trench slanting angle equal to or larger than 80 degrees is formed; and removing a damage portion in such a manner that the damage portion disposed on an inner surface of the trench formed in the semiconductor substrate in the step of forming the trench is etched and removed in hydrogen atmosphere under decompression pressure at a temperature equal to or higher than 1600° C.
    Type: Grant
    Filed: April 14, 2005
    Date of Patent: July 10, 2007
    Assignee: DENSO Corporation
    Inventors: Yuuichi Takeuchi, Rajesh Kumar Malhan, Hiroyuki Matsunami, Tsunenobu Kimoto
  • Publication number: 20060202238
    Abstract: A lateral junction field effect transistor includes a first gate electrode layer arranged in a third semiconductor layer between source/drain region layers, having a lower surface extending on the second semiconductor layer, and doped with p-type impurities more heavily than the second semiconductor layer, and a second gate electrode layer arranged in a fifth semiconductor layer between the source/drain region layers, having a lower surface extending on a fourth semiconductor layer, having substantially the same concentration of p-type impurities as the first gate electrode layer, and having the same potential as the first gate electrode layer. Thereby, the lateral junction field effect transistor has a structure, which can reduce an on-resistance while maintaining good breakdown voltage properties.
    Type: Application
    Filed: April 11, 2006
    Publication date: September 14, 2006
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Kazuhiro Fujikawa, Shin Harada, Kenichi Hirotsu, Satoshi Hatsukawa, Takashi Hoshino, Hiroyuki Matsunami, Tsunenobu Kimoto
  • Publication number: 20060118813
    Abstract: A lateral JFET has a basic structure including an n-type semiconductor layer (3) formed of an n-type impurity region and a p-type semiconductor layer formed of a p-type impurity region on the n-type semiconductor layer (3). Moreover, in the p-type semiconductor layer, there are provided a p+-type gate region layer (7) extending into the n-type semiconductor layer (3) and containing p-type impurities of an impurity concentration higher than that of the n-type semiconductor layer (3) and an n+-type drain region layer (9) spaced from the p+-type gate region layer (7) by a predetermined distance and containing n-type impurities of an impurity concentration higher than that of the n-type semiconductor layer (3). With this structure, the lateral JFET can be provided that has an ON resistance further decreased while maintaining a high breakdown voltage performance.
    Type: Application
    Filed: January 20, 2006
    Publication date: June 8, 2006
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Shin Harada, Kenichi Hirotsu, Hiroyuki Matsunami, Tsunenobu Kimoto
  • Publication number: 20060113574
    Abstract: On an SiC single crystal substrate, an electric field relaxation layer and a p? type buffer layer are formed. The electric field relaxation layer is formed between the p? type buffer layer and the SiC single crystal substrate to contact SiC single crystal substrate. On the p? type buffer layer, an n type semiconductor layer is formed. On the n type semiconductor layer, a p type semiconductor layer is formed. In the p type semiconductor layer, an n+ type source region layer and an n+ type drain region layer are formed separated by a prescribed distance from each other. At a part of the region of p type semiconductor layer between the n+ type source region layer and the n+ type drain region layer, a p+ type gate region layer is formed.
    Type: Application
    Filed: May 21, 2004
    Publication date: June 1, 2006
    Inventors: Kazuhiro Fujikawa, Shin Harada, Hiroyuki Matsunami, Tsunenobu Kimoto
  • Patent number: 7049644
    Abstract: A lateral junction field effect transistor includes a first gate electrode layer arranged in a third semiconductor layer between source/drain region layers, having a lower surface extending on the second semiconductor layer, and doped with p-type impurities more heavily than the second semiconductor layer, and a second gate electrode layer arranged in a fifth semiconductor layer between the source/drain region layers, having a lower surface extending on a fourth semiconductor layer, having substantially the same concentration of p-type impurities as the first gate electrode layer, and having the same potential as the first gate electrode layer. Thereby, the lateral junction field effect transistor has a structure, which can reduce an on-resistance while maintaining good breakdown voltage properties.
    Type: Grant
    Filed: December 2, 2002
    Date of Patent: May 23, 2006
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kazuhiro Fujikawa, Shin Harada, Kenichi Hirotsu, Satoshi Hatsukawa, Takashi Hoshino, Hiroyuki Matsunami, Tsunenobu Kimoto
  • Patent number: 7023033
    Abstract: A lateral JFET has a basic structure including an n-type semiconductor layer (3) formed of an n-type impurity region and a p-type semiconductor layer formed of a p-type impurity region on the n-type semiconductor layer (3). Moreover, in the p-type semiconductor layer, there are provided a p+-type gate region layer (7) extending into the n-type semiconductor layer (3) and containing p-type impurities of an impurity concentration higher than that of the n-type semiconductor layer (3) and an n+-type drain region layer (9) spaced from the p+-type gate region layer (7) by a predetermined distance and containing n-type impurities of an impurity concentration higher than that of the n-type semiconductor layer (3). With this structure, the lateral JFET can be provided that has an ON resistance further decreased while maintaining a high breakdown voltage performance.
    Type: Grant
    Filed: June 11, 2002
    Date of Patent: April 4, 2006
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Shin Harada, Kenichi Hirotsu, Hiroyuki Matsunami, Tsunenobu Kimoto
  • Publication number: 20050233539
    Abstract: A method for manufacturing a silicon carbide semiconductor device includes the steps of: forming a trench mask on an upper surface of a semiconductor substrate; forming the trench such that the trench having an aspect ratio equal to or larger than 2 and having a trench slanting angle equal to or larger than 80 degrees is formed; and removing a damage portion in such a manner that the damage portion disposed on an inner surface of the trench formed in the semiconductor substrate in the step of forming the trench is etched and removed in hydrogen atmosphere under decompression pressure at a temperature equal to or higher than 1600° C.
    Type: Application
    Filed: April 14, 2005
    Publication date: October 20, 2005
    Inventors: Yuuichi Takeuchi, Rajesh Malhan, Hiroyuki Matsunami, Tsunenobu Kimoto
  • Publication number: 20050218414
    Abstract: 4H-InGaAlN alloy based optoelectronic and electronic devices on non-polar face are formed on 4H-AlN or 4H-AlGaN on (11-20) a-face 4H-SiC substrates. Typically, non polar 4H-AlN is grown on 4H-SiC (11-20) by molecular beam epitaxy (MBE). Subsequently, III-V nitride device layers are grown by metal organic chemical vapor deposition (MOCVD) with 4H-polytype for all of the layers. The non-polar device does not contain any built-in electric field due to the spontaneous and piezoelectric polarization. The optoelectonic devices on the non-polar face exhibits higher emission efficiency with shorter emission wavelength because the electrons and holes are not spatially separated in the quantum well. Vertical device configuration for lasers and light emitting diodes(LEDs) using conductive 4H-AlGaN interlayer on conductive 4H-SiC substrates makes the chip size and series resistance smaller. The elimination of such electric field also improves the performance of high speed and high power transistors.
    Type: Application
    Filed: March 30, 2004
    Publication date: October 6, 2005
    Inventors: Tetsuzo Ueda, Tsunenobu Kimoto, Hiroyuki Matsunami, Jun Suda, Norio Onojima
  • Publication number: 20050093017
    Abstract: A lateral junction field effect transistor includes a first gate electrode layer (18A) arranged in a third semiconductor layer (13) between source/drain region layers (6, 8), having a lower surface extending on the second semiconductor layer (12), and doped with p-type impurities more heavily than the second semiconductor layer (12), and a second gate electrode layer (18B) arranged in a fifth semiconductor layer (15) between the source/drain region layers (6, 8), having a lower surface extending on a fourth semiconductor layer (14), having substantially the same concentration of p-type impurities as the first gate electrode layer (18A), and having the same potential as the first gate electrode layer (18A). Thereby, the lateral junction field effect transistor has a structure, which can reduce an on-resistance while maintaining good breakdown voltage properties.
    Type: Application
    Filed: December 2, 2002
    Publication date: May 5, 2005
    Inventors: Kazuhiro Fujikawa, Shin Harada, Kenichi Hirotsu, Satoshi Hatsukawa, Takashi Hoshino, Hiroyuki Matsunami, Tsunenobu Kimoto
  • Patent number: 6870189
    Abstract: A junction field effect transistor (JFET) is provided that is capable of a high voltage resistance, high current switching operation, that operates with a low loss, and that has little variation. This JFET is provided with a gate region (2) of a second conductivity type provided on a surface of a semiconductor substrate, a source region (1) of a first conductivity type, a channel region (10) of the first conductivity type that adjoins the source region, a confining region (5) of the second conductivity type that adjoins the gate region and confines the channel region, a drain region (3) of the first conductivity type provided on a reverse face, and a drift region (4) of the first conductivity type that continuously lies in a direction of thickness of the substrate from a channel to a drain.
    Type: Grant
    Filed: September 11, 2000
    Date of Patent: March 22, 2005
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Shin Harada, Kenichi Hirotsu, Hiroyuki Matsunami, Tsunenobu Kimoto
  • Patent number: 6853006
    Abstract: A silicon carbide (SiC) substrate is provided with an off-oriented {0001} surface whose off-axis direction is <11-20>. A trench is formed on the SiC to have a stripe structure extending toward a <11-20> direction. An SiC epitaxial layer is formed on an inside surface of the trench.
    Type: Grant
    Filed: July 31, 2003
    Date of Patent: February 8, 2005
    Assignee: Denso Corporation
    Inventors: Mitsuhiro Kataoka, Yuuichi Takeuchi, Masami Naito, Rajesh Kumar, Hiroyuki Matsunami, Tsunenobu Kimoto