Patents by Inventor Ryuta Tsuchiya

Ryuta Tsuchiya 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: 9287400
    Abstract: An object of the present invention is to provide a semiconductor device having a fin-type transistor that is excellent in characteristics by forming a fin-shaped semiconductor portion and a gate electrode with high precision or by making improvement regarding variations in characteristics among elements. The present invention is a semiconductor device including a fin-shaped semiconductor portion having a source region formed on one side thereof and a drain region formed on the other side thereof, and a gate electrode formed between the source region and the drain region to surround the fin-shaped semiconductor portion with a gate insulating film interposed therebetween. One solution for solving the problem according to the invention is that the gate electrode uses a metal material or a silicide material that is wet etchable.
    Type: Grant
    Filed: August 16, 2012
    Date of Patent: March 15, 2016
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Toshiaki Iwamatsu, Takashi Terada, Hirofumi Shinohara, Kozo Ishikawa, Ryuta Tsuchiya, Kiyoshi Hayashi
  • Patent number: 9263571
    Abstract: When a gate length is reduced for the purpose of reducing on-resistance in a SiC DOMSFET, it is difficult to achieve both of the reduction of on-resistance by the reduction of gate length and the high element withstand voltage at the same time. In the present invention, a body layer is formed after the source diffusion layer region is formed and then a portion of the source diffusion layer region is recessed. Because of the presence of the body layer, the distances between the source diffusion region and respective end portions can be increased, a depletion layer is effectively expanded, and electric field concentration at the end portions can be suppressed, thereby improving withstand voltage characteristics. Consequently, the present invention can provide a silicon carbide semiconductor device that achieves both of the reduction of channel resistance by the reduction of gate length and the high element withstand voltage at the same time.
    Type: Grant
    Filed: December 28, 2012
    Date of Patent: February 16, 2016
    Assignee: Hitachi, Ltd.
    Inventors: Ryuta Tsuchiya, Hiroyuki Matsushima, Naoki Tega, Digh Hisamoto
  • Patent number: 9257583
    Abstract: A solar cell including a substrate 1, a nanopillar 11 having diameter D1 connected to the substrate 1, and a nanopillar 12 having diameter D2 connected to the substrate 1 is characterized in that D2 is greater than D1 in order to realize a solar cell having, as the surface structure, a nanopillar array structure with which it is possible to prevent reflection within the broad wavelength region of solar light. A nanopillar array structure 21 formed from two types of nanopillars having different diameters has a point of minimum reflectivity of a nanopillar array structure formed from the nanopillar 11 having diameter D1 and a point of minimum reflectivity of a nanopillar array structure formed from the nanopillar 12 having diameter D2 and therefore, is capable of preventing reflection within the broad wavelength region of solar light.
    Type: Grant
    Filed: May 25, 2011
    Date of Patent: February 9, 2016
    Assignee: HITACHI, LTD.
    Inventors: Keiji Watanabe, Ryuta Tsuchiya, Takashi Hattori, Mieko Matsumura
  • Publication number: 20150349115
    Abstract: Disclosed herein is a technique for realizing a high-performance and high-reliability silicon carbide semiconductor device. A trenched MISFET with a trench formed into the drift through a p-type body layer 105 includes an n-type resistance relaxation layer 109 covering the bottom portion of the trench, and a p-type field relaxation layer 108. The p-type field relaxation layer 108 is separated from the trench bottom portion via the resistance relaxation layer 109, and is wider than the resistance relaxation layer 109. This achieves a low ON resistance, high reliability, and high voltage resistance at the same time. By forming the field relaxation layer beneath the trench, feedback capacitance can be controlled to achieve a high switching rate and high reliability.
    Type: Application
    Filed: January 23, 2013
    Publication date: December 3, 2015
    Inventors: Naoki TEGA, Digh HISAMOTO, Satoru AKIYAMA, Takashi TAKAHAMA, Tadao MORIMOTO, Ryuta TSUCHIYA
  • Publication number: 20150318389
    Abstract: When a gate length is reduced for the purpose of reducing on-resistance in a SiC DOMSFET, it is difficult to achieve both of the reduction of on-resistance by the reduction of gate length and the high element withstand voltage at the same time. In the present invention, a body layer is formed after the source diffusion layer region is formed and then a portion of the source diffusion layer region is recessed. Because of the presence of the body layer, the distances between the source diffusion region and respective end portions can be increased, a depletion layer is effectively expanded, and electric field concentration at the end portions can be suppressed, thereby improving withstand voltage characteristics. Consequently, the present invention can provide a silicon carbide semiconductor device that achieves both of the reduction of channel resistance by the reduction of gate length and the high element withstand voltage at the same time.
    Type: Application
    Filed: December 28, 2012
    Publication date: November 5, 2015
    Inventors: Ryuta TSUCHIYA, Hiroyuki MATSUSHIMA, Naoki TEGA, Digh HISAMOTO
  • Patent number: 9029979
    Abstract: A trench groove is formed and a silicon oxide film is buried in the periphery of a channel region of (0001) surface 4h-SiC semiconductor element. The oxide film in the trench groove is defined in such a planar layout that a tensile strain is applied along the direction of the c-axis and a compressive strain is applied along two or more of axes on a plane perpendicular to the c-axis. For example, trench grooves buried with an oxide film may be configured to such a layout that they are in a trigonal shape surrounding the channel, or are arranged symmetrically with respect to the channel as a center when arranged discretely.
    Type: Grant
    Filed: November 23, 2012
    Date of Patent: May 12, 2015
    Assignee: Hitachi, Ltd.
    Inventors: Hiroyuki Yoshimoto, Ryuta Tsuchiya, Naoki Tega, Digh Hisamoto, Yasuhiro Shimamoto, Yuki Mori
  • Publication number: 20150053261
    Abstract: A surface reflectivity of a solar cell is reduced by applying a nanopillar array including a plurality of nanopillars to the solar cell. Further, by constituting the nanopillars with a Si/SiGe superlattice and controlling a Ge composition ratio of a SiGe layer (2), excited electron and hole are spatially separated in different layers, thus increasing a carrier lifetime, and at the same time, an optical-electrical conversion efficiency is improved by a multi-exciton phenomenon due to a quantum confinement effect. In addition, by forming an intermediate band by thinning a Si layer (1) and the SiGe layer (2), a carrier extraction efficiency is improved.
    Type: Application
    Filed: August 29, 2011
    Publication date: February 26, 2015
    Applicant: HITACHI, LTD.
    Inventors: Ryuta Tsuchiya, Keiji Watanabe, Takashi Hattori, Mieko Matsumura
  • Patent number: 8790948
    Abstract: In the existent method for manufacturing a solar cell, manufacture of a solar cell having a quantum well having a crystalline well layer and capable of controlling the thickness of the well layer was difficult. A quantum well having an amorphous well layer, comprising a barrier layer and an amorphous well layer is formed and then the quantum well having the amorphous well layer is annealed thereby crystallizing the amorphous well layer to form a quantum well having a crystalline well layer. By applying energy density applied to the amorphous well layer at an energy density of 1.26 J/mm2 or more and 28.8 J/mm2 or less, the crystalline well layer can be formed and the lamination structure of the quantum well can be maintained simultaneously.
    Type: Grant
    Filed: November 23, 2011
    Date of Patent: July 29, 2014
    Assignee: Hitachi, Ltd.
    Inventors: Keiji Watanabe, Toshiyuki Mine, Akio Shima, Tomoko Sekiguchi, Ryuta Tsuchiya
  • Publication number: 20140166100
    Abstract: A solar cell including a substrate 1, a nanopillar 11 having diameter D1 connected to the substrate 1, and a nanopillar 12 having diameter D2 connected to the substrate 1 is characterized in that D2 is greater than D1 in order to realize a solar cell having, as the surface structure, a nanopillar array structure with which it is possible to prevent reflection within the broad wavelength region of solar light. A nanopillar array structure 21 formed from two types of nanopillars having different diameters has a point of minimum reflectivity of a nanopillar array structure formed from the nanopillar 11 having diameter D1 and a point of minimum reflectivity of a nanopillar array structure formed from the nanopillar 12 having diameter D2 and therefore, is capable of preventing reflection within the broad wavelength region of solar light.
    Type: Application
    Filed: May 25, 2011
    Publication date: June 19, 2014
    Applicant: HITACHI, LTD.
    Inventors: Keiji Watanabe, Ryuta Tsuchiya, Takashi Hattori, Mieko Matsumura
  • Patent number: 8710550
    Abstract: A semiconductor device includes a nitride semiconductor stack having at least two hetero junction bodies where a first nitride semiconductor layer and a second nitride semiconductor layer having a band gap wider than that of the first nitride semiconductor layer are disposed, and includes a drain electrode and, a source electrode disposed to the nitride semiconductor stack, and gate electrodes at a position put between the drain electrode and the source electrode and disposed so as to oppose them respectively in which the drain electrode and the source electrode are disposed over the surface or on the lateral side of the nitride semiconductor stack, and the gate electrode has a first gate electrode disposed in the direction of the depth of the nitride semiconductor stack and a second gate electrode disposed in the direction of the depth of the nitride semiconductor at a depth different from the first gate electrode.
    Type: Grant
    Filed: October 31, 2012
    Date of Patent: April 29, 2014
    Assignee: Hitachi, Ltd.
    Inventors: Takashi Ishigaki, Ryuta Tsuchiya, Kazuhiro Mochizuki, Akihisa Terano
  • Patent number: 8643117
    Abstract: In an SOI-MISFET that operates with low power consumption at a high speed, an element area is reduced. While a diffusion layer region of an N-conductivity type MISFET region of the SOI type MISFET and a diffusion layer region of a P-conductivity type MISFET region of the SOI type MISFET are formed as a common region, well diffusion layers that apply substrate potentials to the N-conductivity type MISFET region and the P-conductivity type MISFET region are separated from each other by an STI layer. The diffusion layer regions that are located in the N- and P-conductivity type MISFET regions) and serve as an output portion of a CMISFET are formed as a common region and directly connected by silicified metal so that the element area is reduced.
    Type: Grant
    Filed: January 18, 2010
    Date of Patent: February 4, 2014
    Assignee: Hitachi, Ltd.
    Inventors: Ryuta Tsuchiya, Nobuyuki Sugii, Yusuke Morita, Hiroyuki Yoshimoto, Takashi Ishigaki, Shinichiro Kimura
  • Publication number: 20130240991
    Abstract: A device and a method for manufacturing the same in which with device includes a single crystal semiconductor substrate and an SOI substrate separated from the single crystal semiconductor substrate by a thin buried insulating film and having a thin single crystal semiconductor thin film (SOI layer), in which well diffusion layer regions, drain regions, gate insulating films, and gate electrodes of the SOI-type MISFET and the bulk-type MISFET are formed in the same steps. The bulk-type MISFET and the SOI-type MISFET are formed on the same substrate, so that board area is reduced and a simple process can be realized by making manufacturing steps of the SOI-type MISFET and the bulk-type MISFET common.
    Type: Application
    Filed: March 4, 2013
    Publication date: September 19, 2013
    Applicant: RENESAS ELECTRONICS CORPORATION
    Inventors: Ryuta TSUCHIYA, Shinichiro KIMURA
  • Patent number: 8409936
    Abstract: A device and a method for manufacturing the same in which with device includes a single crystal semiconductor substrate and an SOI substrate separated from the single crystal semiconductor substrate by a thin buried insulating film and having a thin single crystal semiconductor thin film (SOI layer) in which well diffusion layer regions, drain regions, gate insulating films, and gate electrodes of the SOI-type MISFET and the bulk-type MISFET are formed in the same steps. The bulk-type MISFET and the SOI-type MISFET are formed on the same substrate, so that board area is reduced and a simple process can be realized by making manufacturing steps of the SOI-type MISFET and the bulk-type MISFET common.
    Type: Grant
    Filed: January 31, 2012
    Date of Patent: April 2, 2013
    Assignee: Renesas Electronics Corporation
    Inventors: Ryuta Tsuchiya, Shinichiro Kimura
  • Patent number: 8350328
    Abstract: Characteristics of a semiconductor device having a FINFET are improved. The FINFET has: a channel layer arranged in an arch shape on a semiconductor substrate and formed of monocrystalline silicon; a front gate electrode formed on a part of an outside of the channel layer through a front gate insulating film; and a back gate electrode formed so as to be buried inside the channel layer through a back gate insulating film. The back gate electrode arranged inside the arch shape is arranged so as to pass through the front gate electrode.
    Type: Grant
    Filed: April 13, 2010
    Date of Patent: January 8, 2013
    Assignee: Hitachi, Ltd.
    Inventors: Takashi Ishigaki, Ryuta Tsuchiya, Yusuke Morita, Nobuyuki Sugii
  • Publication number: 20120318337
    Abstract: In a conventional solar cell, it has been difficult to ensure a sufficient light absorption and simultaneously to prevent current loss due to the reduction of the moving distance of electrons and holes. As a means for solving this difficulty, a plurality of a p-i-n junctions are stacked through an insulating film and are connected in parallel with each other using through-electrodes. In this case, the through-electrodes and the p-i-n junctions are connected through the p-layer or the n-layer, thereby moving electrons and holes in opposite directions and generating output current. In addition, the i-layer is made thicker than the p-layer and the n-layer in each of the p-i-n junctions, thereby ensuring a sufficient light absorption and simultaneously preventing current loss.
    Type: Application
    Filed: February 17, 2012
    Publication date: December 20, 2012
    Inventors: Keiji Watanabe, Takashi Hattori, Mieko Matsumura, Ryuta Tsuchiya, Mutsuko Hatano
  • Publication number: 20120309157
    Abstract: An object of the present invention is to provide a semiconductor device having a fin-type transistor that is excellent in characteristics by forming a fin-shaped semiconductor portion and a gate electrode with high precision or by making improvement regarding variations in characteristics among elements. The present invention is a semiconductor device including a fin-shaped semiconductor portion having a source region formed on one side thereof and a drain region formed on the other side thereof, and a gate electrode formed between the source region and the drain region to surround the fin-shaped semiconductor portion with a gate insulating film interposed therebetween. One solution for solving the problem according to the invention is that the gate electrode uses a metal material or a silicide material that is wet etchable.
    Type: Application
    Filed: August 16, 2012
    Publication date: December 6, 2012
    Inventors: Toshiaki IWAMATSU, Takashi TERADA, Hirofumi SHINOHARA, Kozo ISHIKAWA, Ryuta TSUCHIYA, Kiyoshi HAYASHI
  • Patent number: 8269288
    Abstract: An object of the present invention is to provide a semiconductor device having a fin-type transistor that is excellent in characteristics by forming a fin-shaped semiconductor portion and a gate electrode with high precision or by making improvement regarding variations in characteristics among elements. The present invention is a semiconductor device including a fin-shaped semiconductor portion having a source region formed on one side thereof and a drain region formed on the other side thereof, and a gate electrode formed between the source region and the drain region to surround the fin-shaped semiconductor portion with a gate insulating film interposed therebetween. One solution for solving the problem according to the invention is that the gate electrode uses a metal material or a silicide material that is wet etchable.
    Type: Grant
    Filed: October 17, 2008
    Date of Patent: September 18, 2012
    Assignee: Renesas Electronics Corporation
    Inventors: Toshiaki Iwamatsu, Takashi Terada, Hirofumi Shinohara, Kozo Ishikawa, Ryuta Tsuchiya, Kiyoshi Hayashi
  • Publication number: 20120196411
    Abstract: A device and a method for manufacturing the same in which with device includes a single crystal semiconductor substrate and an SOI substrate separated from the single crystal semiconductor substrate by a thin buried insulating film and having a thin single crystal semiconductor thin film (SOI layer) in which well diffusion layer regions, drain regions, gate insulating films, and gate electrodes of the SOI-type MISFET and the bulk-type MISFET are formed in the same steps. The bulk-type MISFET and the SOI-type MISFET are formed on the same substrate, so that board area is reduced and a simple process can be realized by making manufacturing steps of the SOI-type MISFET and the bulk-type MISFET common.
    Type: Application
    Filed: January 31, 2012
    Publication date: August 2, 2012
    Inventors: Ryuta TSUCHIYA, Shinichiro Kimura
  • Publication number: 20120149143
    Abstract: In the existent method for manufacturing a solar cell, manufacture of a solar cell having a quantum well having a crystalline well layer and capable of controlling the thickness of the well layer was difficult. A quantum well having an amorphous well layer, comprising a barrier layer and an amorphous well layer is formed and then the quantum well having the amorphous well layer is annealed thereby crystallizing the amorphous well layer to form a quantum well having a crystalline well layer. By applying energy density applied to the amorphous well layer at an energy density of 1.26 J/mm2 or more and 28.8 J/mm2 or less, the crystalline well layer can be formed and the lamination structure of the quantum well can be maintained simultaneously.
    Type: Application
    Filed: November 23, 2011
    Publication date: June 14, 2012
    Applicant: Hitachi, Ltd.
    Inventors: Keiji WATANABE, Toshiyuki MINE, Akio SHIMA, Tomoko SEKIGUCHI, Ryuta TSUCHIYA
  • Patent number: 8183635
    Abstract: A technique to be applied to a semiconductor device for achieving low power consumption by improving a shape at a boundary portion of a shallow trench and an SOI layer of an SOI substrate. A position (SOI edge) at which a main surface of a silicon substrate and a line extended along a side surface of an SOI layer are crossed is recessed away from a shallow-trench isolation more than a position (STI edge) at which a line extended along a sidewall of a shallow trench and a line extended along the main surface of the silicon substrate are crossed, and a corner of the silicon substrate at the STI edge has a curved surface.
    Type: Grant
    Filed: April 8, 2010
    Date of Patent: May 22, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Nobuyuki Sugii, Ryuta Tsuchiya, Shinichiro Kimura, Takashi Ishigaki, Yusuke Morita, Hiroyuki Yoshimoto