Patents by Inventor Yoshiki Nishibayashi

Yoshiki Nishibayashi 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: 20070272929
    Abstract: The present invention relates to a diamond n-type semiconductor in which the amount of change in carrier concentration is fully reduced in a wide temperature range. The diamond n-type semiconductor comprises a diamond substrate, and a diamond semiconductor formed on a main surface thereof and turned out to be n-type. The diamond semiconductor exhibits a carrier concentration (electron concentration) negatively correlated with temperature in a part of a temperature region in which it is turned out to be n-type, and a Hall coefficient positively correlated with temperature. The diamond n-type semiconductor having such a characteristic is obtained, for example, by forming a diamond semiconductor doped with a large amount of a donor element while introducing an impurity other than the donor element onto the diamond substrate.
    Type: Application
    Filed: November 17, 2004
    Publication date: November 29, 2007
    Inventors: Akihiko Namba, Yoshiki Nishibayashi, Takahiro Imai
  • Publication number: 20070111498
    Abstract: An n-type diamond epitaxial layer 20 is formed by processing a single-crystalline {100} diamond substrate 10 so as to form a {111} plane, and subsequently by causing diamond to epitaxially grow while n-doping the diamond {111} plane. Further, a combination of the n-type semiconductor diamond, p-type semiconductor diamond, and non-doped diamond, obtained in the above-described way, as well as the use of p-type single-crystalline {100} diamond substrate allow for a pn junction type, a pnp junction type, an npn junction type and a pin junction type semiconductor diamond to be obtained.
    Type: Application
    Filed: January 10, 2007
    Publication date: May 17, 2007
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Akihiko Nambo, Takahiro Imai, Yoshiki Nishibayashi
  • Patent number: 7172957
    Abstract: An n-type diamond epitaxial layer 20 is formed by processing a single-crystalline {100} diamond substrate 10 so as to form a {111} plane, and subsequently by causing diamond to epitaxially grow while n-doping the diamond {111} plane. Further, a combination of the n-type semiconductor diamond, p-type semiconductor diamond, and non-doped diamond, obtained in the above-described way, as well as the use of p-type single-crystalline {100} diamond substrate allow for a pn junction type, a pnp junction type, an npn junction type and a pin junction type semiconductor diamond to be obtained.
    Type: Grant
    Filed: December 17, 2004
    Date of Patent: February 6, 2007
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Akihiko Namba, Takahiro Imai, Yoshiki Nishibayashi
  • Patent number: 7147918
    Abstract: A diamond electron emission element is provided with a substrate, and a plurality of quadrangular columns (microscopic projections) composed of diamond and with side faces of flat faces, which are arranged at equal intervals on the substrate. A top end face (horizontal section) is of a quadrangular shape having a length of long sides being a [nm] and a length of short sides being ka [nm], and a thin film of SiO2 is formed on a side face on the short-edge side. The length a [nm] of long sides and the length ka [nm] of short sides satisfy relational expressions of Formulae (1) and (2) below. C1=2a?{square root over (1+k2)}??(1) n?=C1??(2) C1: a distance [nm] of a lap in a situation where light generated inside each quadrangular column goes around on a specific circuit while being reflected on the side faces of the quadrangular column, n: an arbitrary positive integer, and ?: an emission peak wavelength ? [nm] of the diamond making the quadrangular columns.
    Type: Grant
    Filed: September 15, 2003
    Date of Patent: December 12, 2006
    Assignees: Sumitomo Electric Industries, Ltd., Japan Fine Ceramics Center
    Inventors: Yoshiki Nishibayashi, Yutaka Ando, Takahiro Imai
  • Publication number: 20060244352
    Abstract: An electron emission device which is smaller, able to operate at lower voltage and more efficient than the conventional device is provided. The device contains a light emitting device to irradiate light to a cathode wherein at least an electron emission face of the cathode is made of diamond. By composing the device in such a way, the voltage to draw out electrons can be lowered with a wide margin compared to the conventional device, and thus a small device which can be operated with low voltage may be obtained. The light emitting device can be formed as one unit with the cathode and it can also be that the light emitting device and the electrode are made of diamond. Furthermore, the electron emission face of the cathode is preferably an n- or p-type diamond semiconductor.
    Type: Application
    Filed: September 15, 2004
    Publication date: November 2, 2006
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Natsuo Tatsumi, Yoshiki Nishibayashi, Takahiro Imai
  • Publication number: 20060220514
    Abstract: A method for production includes a step for forming concaved molds on a surface of a substrate and a step for growing a diamond heteroepitaxially on the substrate in an atmosphere containing a doping material. The crystal structure of the slope of the concaved molds of the substrate can have the cubic system crystal orientation (111), and the doping material is phosphorous. Further, the substrate is Si, and the slope of the molds can be the Si (111) face. The diamond electron emission device contains projection parts on the surface thereof, where a slope of the projection parts 1 contains a diamond (111) face, and flat parts 2, which are not the projection parts, contain face orientations other than (100) face or (110) face and grain boundaries.
    Type: Application
    Filed: September 29, 2004
    Publication date: October 5, 2006
    Inventors: Natsuo Tatsumi, Akihiko Namba, Yoshiki Nishibayashi, Takahiro Imai
  • Publication number: 20060177962
    Abstract: A method of manufacturing n-type semiconductor diamond by the present invention is characterized in producing diamond incorporating Li and N by implanting Li ions into, so that 10 ppm thereof will be contained in, single-crystal diamond incorporating 10 ppm or more N, or else, in doping single-crystal diamond with Li and N ions, by implanting the ions so that ion-implantation depths at which the post-implantation Li and N concentrations each are 10 ppm or more will overlap, and thereafter annealing the diamond in a temperature range of from 800° C. or more to less than 1800° C. to electrically activate the Li and N and restore the diamond crystalline structure. In the present invention, n-type semiconductor diamond incorporates, from the surface of the crystal to the same depth, 10 ppm or more of each of Li and N, wherein its sheet resistance is 107 ?/? or less.
    Type: Application
    Filed: December 22, 2003
    Publication date: August 10, 2006
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Akihiko Namba, Yoshiyuki Yamamoto, Hitoshi Sumiya, Yoshiki Nishibayashi, Takahiro Imai
  • Patent number: 7026750
    Abstract: An electron emission element of the present invention comprises a substrate, and a protrusion protruding from the substrate and including boron-doped diamond. The protrusion comprises a columnar body. And a tip portion of the protrusion comprises an acicular body sticking out therefrom. The distance r [cm] between a center axis and a side face in the columnar body and the boron concentration Nb [cm?3] in the diamond satisfy the relationship represented by the following formula (1): r > 10 4 Nb .
    Type: Grant
    Filed: September 22, 2003
    Date of Patent: April 11, 2006
    Assignees: Sumitomo Electric Industries, Ltd., Japan Fine Ceramics Center
    Inventors: Yoshiki Nishibayashi, Takahiro Imai, Yutaka Ando
  • Publication number: 20060044036
    Abstract: A logical operation element and logical operation circuit are provided that are capable of high speed and a high degree of integration. A logical operation circuit has a construction wherein, in a logical operation element, the anodes of first and second field emission type microfabricated electron emitters are put at the same potential and two or more signal voltages are input to gate electrodes corresponding to these emitters. A NOR element so arranged that when a high potential input signal is input to either of the two lines, electron emission occurs from the emitters and the potential of said anodes is lowered, and a NAND element wherein the cathodes of the first and second field emission type microfabricated electron emitters are connected in series, two signal voltages are applied to the gate electrodes corresponding to the first and second emitter and the anode potential of the second emitter is lowered when the two input signals are high potential are employed.
    Type: Application
    Filed: March 5, 2004
    Publication date: March 2, 2006
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Natsuo Tatsumi, Yoshiki Nishibayashi, Takahiro Imai, Tsuneo Nakahara
  • Patent number: 6958571
    Abstract: A method of manufacturing an electron-emitting element (20) for emitting electrons from diamond includes the first step of forming a diamond columnar member (25) on a diamond substrate (21), and the second step of forming an electron-emitting portion (30) having a base portion (36) and a sharp-pointed portion (32) which is located closer to a distal end side than the base portion (36) and emits the electrons by performing etching processing with respect to the columnar member (25).
    Type: Grant
    Filed: August 30, 2001
    Date of Patent: October 25, 2005
    Assignees: Sumitomo Electric Industries, Ltd., Japan Fine Ceramics Center
    Inventors: Yoshiki Nishibayashi, Yutaka Ando, Kiichi Meguro, Takahiro Imai
  • Publication number: 20050202665
    Abstract: An n-type diamond epitaxial layer 20 is formed by processing a single-crystalline {100} diamond substrate 10 so as to form a {111} plane, and subsequently by causing diamond to epitaxially grow while n-doping the diamond {111} plane. Further, a combination of the n-type semiconductor diamond, p-type semiconductor diamond, and non-doped diamond, obtained in the above-described way, as well as the use of p-type single-crystalline {100} diamond substrate allow for a pn junction type, a pnp junction type, an npn junction type and a pin junction type semiconductor diamond to be obtained.
    Type: Application
    Filed: December 17, 2004
    Publication date: September 15, 2005
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Akihiko Namba, Takahiro Imai, Yoshiki Nishibayashi
  • Publication number: 20050133735
    Abstract: The present invention relates to an electron emitting device having a structure for efficiently emitting electrons. The electron emitting device has a substrate comprised of an n-type diamond, and a pointed projection provided on the substrate. The projection comprises a base provided on the substrate side, and an electron emission portion provided on the base and emitting electrons from the tip thereof. The base is comprised of an n-type diamond. The electron emission portion is comprised of a p-type diamond. The length from the tip of the projection (electron emission portion) to the interface between the base and the electron emission portion is preferably 100 nm or less.
    Type: Application
    Filed: September 29, 2004
    Publication date: June 23, 2005
    Inventors: Natsuo Tatsumi, Akihiko Namba, Yoshiki Nishibayashi, Takahiro Imai
  • Patent number: 6876136
    Abstract: An electron emission element according to the present invention comprises a substrate, and a plurality of protrusions composed of diamond and protruding from the substrate. Each protrusion includes a columnar portion, the side face of which forms an inclination of approximately 90° relative to the surface of the substrate, and a tip portion, which is located on the columnar portion having a spicular end. A conductive layer is formed on the upper part of each columnar portion, and a cathode electrode film, which is electrically connected to the conductive layer, is formed on the side face of the columnar portion.
    Type: Grant
    Filed: September 12, 2003
    Date of Patent: April 5, 2005
    Assignees: Sumitomo Electric Industries, Ltd., Japan Fine Ceramics Center
    Inventors: Yoshiki Nishibayashi, Yutaka Ando, Takahiro Imai
  • Publication number: 20050000938
    Abstract: The method of making a diamond product in accordance with the present invention comprises the steps of forming a diamond substrate (50) with a mask layer (52), and etching the diamond substrate (50) formed with the mask layer (52) with a plasma of a mixed gas composed of a gas containing an oxygen atom and a gas containing a fluorine atom, whereas the fluorine atom concentration is within the range of 0.04% to 6% with respect to the total number of atoms in the mixed gas.
    Type: Application
    Filed: February 10, 2004
    Publication date: January 6, 2005
    Applicants: SUMITOMO ELECTRIC INDUSTRIES, LTD., JAPAN FINE CERAMICS CENTER
    Inventors: Yoshiki Nishibayashi, Kiichi Meguro, Takahiro Imai, Yutaka Ando
  • Publication number: 20040095051
    Abstract: An electron emission element of the present invention comprises a substrate, and a protrusion protruding from the substrate and including boron-doped diamond. The protrusion comprises a columnar body. And a tip portion of the protrusion comprises an acicular body sticking out therefrom. The distance r [cm] between a center axis and a side face in the columnar body and the boron concentration Nb [cm−3] in the diamond satisfy the relationship represented by the following formula (1): 1 r > 10 4 Nb .
    Type: Application
    Filed: September 22, 2003
    Publication date: May 20, 2004
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD. JAPAN FINE CERAMICS CENTER
    Inventors: Yoshiki Nishibayashi, Takahiro Imai, Yutaka Ando
  • Publication number: 20040056580
    Abstract: An electron emission element according to the present invention comprises a substrate, and a plurality of protrusions composed of diamond and protruding from the substrate. Each protrusion includes a columnar portion, the side face of which forms an inclination of approximately 90° relative to the surface of the substrate, and a tip portion, which is located on the columnar portion having a spicular end. A conductive layer is formed on the upper part of each columnar portion, and a cathode electrode film, which is electrically connected to the conductive layer, is formed on the side face of the columnar portion.
    Type: Application
    Filed: September 12, 2003
    Publication date: March 25, 2004
    Applicants: SUMITOMO ELECTRIC INDUSTRIES, LTD., JAPAN FINE CERAMICS CENTER
    Inventors: Yoshiki Nishibayashi, Yutaka Ando, Takahiro Imai
  • Publication number: 20040058539
    Abstract: A diamond electron emission element is provided with a substrate, and a plurality of quadrangular columns (microscopic projections) composed of diamond and with side faces of flat faces, which are arranged at equal intervals on the substrate. A top end face (horizontal section) is of a quadrangular shape having a length of long sides being a [nm] and a length of short sides being ka [nm], and a thin film of SiO2 is formed on a side face on the short-edge side. The length a [nm] of long sides and the length ka [nm] of short sides satisfy relational expressions of Formulae (1) and (2) below.
    Type: Application
    Filed: September 15, 2003
    Publication date: March 25, 2004
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD. JAPAN FINE CERAMICS CENTER
    Inventors: Yoshiki Nishibayashi, Yutaka Ando, Takahiro Imai
  • Patent number: 6709730
    Abstract: The method of making a diamond product in accordance with the present invention comprises the steps of forming a diamond substrate (50) with a mask layer (52), and etching the diamond substrate (50) formed with the mask layer (52) with a plasma of a mixed gas composed of a gas containing an oxygen atom and a gas containing a fluorine atom, whereas the fluorine atom concentration is within the range of 0.04% to 6% with respect to the total number of atoms in the mixed gas.
    Type: Grant
    Filed: November 29, 2001
    Date of Patent: March 23, 2004
    Assignees: Sumitomo Electric Industries, Ltd., Japan Fine Ceramics Center
    Inventors: Yoshiki Nishibayashi, Kiichi Meguro, Takahiro Imai, Yutaka Ando
  • Patent number: 6423982
    Abstract: An electrical connection board includes a diamond substrate and an implantation metal layer constituted by the presence of metal elements in the diamond substrate. The metal layer has a thickness of at least 10 nm and a concentration of at least 1020 cm−3 in the diamond substrate. The implantation metal layer is formed by ion implanting metal elements with a high energy level of at least 1 MeV and a high dose of at least 1016 cm−2. Thus, a technique is provided by which a multi-layer electrical interconnection is realized in the diamond substrate having the highest thermal conductivity of all known materials.
    Type: Grant
    Filed: January 16, 2001
    Date of Patent: July 23, 2002
    Assignees: Japan Fine Ceramics Center, Sumitomo Electric Industries, Ltd.
    Inventors: Yoshiki Nishibayashi, Takashi Matsuura, Takahiro Imai
  • Publication number: 20020064496
    Abstract: The method of making a diamond product in accordance with the present invention comprises the steps of forming a diamond substrate (50) with a mask layer (52), and etching the diamond substrate (50) formed with the mask layer (52) with a plasma of a mixed gas composed of a gas containing an oxygen atom and a gas containing a fluorine atom, whereas the fluorine atom concentration is within the range of 0.04% to 6% with respect to the total number of atoms in the mixed gas.
    Type: Application
    Filed: November 29, 2001
    Publication date: May 30, 2002
    Inventors: Yoshiki Nishibayashi, Kiichi Meguro, Takahiro Imai, Yutaka Ando