Patents by Inventor Yoshiji Horikoshi

Yoshiji Horikoshi 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: 4882609
    Abstract: A semiconductor device consisting of epitaxial material is provided with at least one monoatomic layer of doping atoms, i.e. with a layer which is just one atom thick. A particularly preferred device is a field effect transistor in which case the Dirac-delta doped layer 13 extends between the source and drain zones (18, 19) respectively. The field effect transistor can be constructed either with a homogeneous structure or with a hetero structure or with a superlattice structure. The field effect transistors described herein have a high transconductance and are capable of operating at high current densities.
    Type: Grant
    Filed: November 14, 1985
    Date of Patent: November 21, 1989
    Assignee: Max-Planck Gesellschaft zur Forderung der Wissenschafter e.V.
    Inventors: Erdmann Schubert, Klaus Ploog, Albrecht Fischer, Yoshiji Horikoshi
  • Patent number: 4829022
    Abstract: A method of forming a III-V semiconductor on the surface of a substrate which is placed in a vacuum chamber and is heated, by supplying one element of Group III and one element of Group V of the periodic table in the form of atoms or molecules to the surface of the substrate. The supply of the element of Group V is decreased to a small quantity insufficient to form a III-V compound semiconductor at least at one period of the growth of the III-V compound, and the element of Group V in the small quantity and the element of Group III are supplied to the surface of the substrate. This method makes it possible to grow III-V compound epitaxial layers which have a high degree of purity and fewer crystal defects and in which surfaces and the interfaces of the heterojunctions are flat on an atomic scale, at a wide temperature range. The present invention can be used for the fabrication of various optical devices and super-high-speed electronic devices.
    Type: Grant
    Filed: August 5, 1987
    Date of Patent: May 9, 1989
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Naoki Kobayashi, Hideo Sugiura, Yoshiji Horikoshi
  • Patent number: 4775881
    Abstract: A semiconductor device of the doping superlattice type for detecting electromagnetic radiation or particles comprises a semi-insulating substrate (10), a first layer (11) of either n-type or p-type conductivity deposited thereon, a plurality of layers (12, 13, 14) of alternating conductivity types deposited in series on said first layer (11), a strongly p-type electrode region which extends through said p-type and n-type layers (11, 12, 13, 14) and defines a first selective electrode (15), and a strongly n-type electrode region which also extends through said p-type and n-type layers (11, 12, 13, 14), and which is spaced apart from said strongly p-type region and defines a second selective electrode. The device is a homogeneous semiconductor in which the n-type and p-type layers other than the first layer (11) and the outermost layer (14)have substantially identical thicknesses and doping concentrations.
    Type: Grant
    Filed: February 13, 1987
    Date of Patent: October 4, 1988
    Assignee: Max-Planck-Gesellschaft zur Forderung der Wissenschaften e.V.
    Inventors: Klaus Ploog, Yoshiji Horikoshi
  • Patent number: 4767494
    Abstract: A compound semiconductor thin film is formed by growing a plurality of molecular layers one over another. According to the present invention, while a carrier gas and a small quantity of hydride containing an element in Group V or VI are normally flowed, an organometallic compound which is diluted with hydrogen and which contains an element in Group III or II and a hydride which is diluted with hydrogen and which contains an element in Group V or VI are alternately introduced over a substrate so that an atomic layer of an element in Group III or II and an atomic layer of an element in Group V or VI are alternately grown over the substrate. According to this method, grown layers having a high degree of purity can be obtained. A portion such as a Ga-Ga two-layer structure formed in the growth of a surface of an element in Group III or II can easily be eliminated by the introduction of a hydrogen halide so that the surface defects and deep levels are significantly decreased and perfect crystals can be obtained.
    Type: Grant
    Filed: September 19, 1986
    Date of Patent: August 30, 1988
    Assignee: Nippon Telegraph & Telephone Corporation
    Inventors: Naoki Kobayashi, Toshiki Makimoto, Yoshiji Horikoshi
  • Patent number: 4030949
    Abstract: Disclosed is a method of yielding a multilayer-liquid phase epitaxial growth of Al.sub.x Ga.sub.1.sub.-x As and GaAs for manufacturing a double heterostructure laser, light emitting diode, etc., which is characterized in that hydrogen gas or inert gas, containing GaCl gas, is used as an atmosphere for the epitaxial growth. This method permits the liquid phase epitaxial growth of a semiconductor layer even on an Al.sub.x Ga.sub.1.sub.-x As (x .gtoreq. 0.3) which is once exposed to the air or subjected to an etching treatment. Accordingly, this method is suitable for the manufacture of a semiconductor element having a buried active layer. This method also permits the manufacture of an epitaxial wafer having a low dislocation density.
    Type: Grant
    Filed: June 26, 1975
    Date of Patent: June 21, 1977
    Assignee: Nippon Telegraph and Telephone Public Corporation
    Inventors: Yoshiji Horikoshi, Yoshitaka Furukawa
  • Patent number: 4028148
    Abstract: A method of epitaxially growing a laminate semiconductor layer in liquid phase on the crystalline surface of a substrate by successively bringing different kinds of liquid phase epitaxial growth solution into contact with the surface of a substrate, which is characterized in that different kinds of liquid phase epitaxial growth solutions are injected one after another into solution receptacle, the bottom of which is open to the substrate surface, and each of the preceding one of the epitaxial growth solutions is expelled from the solution receptacle by each succeeding one of the epitaxial growth solutions for interchange between both solutions and thereafter each succeeding solution is epitaxially grown on the preceding one.
    Type: Grant
    Filed: August 19, 1976
    Date of Patent: June 7, 1977
    Assignee: Nippon Telegraph and Telephone Public Corporation
    Inventor: Yoshiji Horikoshi
  • Patent number: 4013040
    Abstract: Apparatus for epitaxially growing a laminate semiconductor layer in liquid phase on the crystalline surface of a substrate by successively bringing different kinds of liquid phase epitaxial growth solution into contact with the surface of a substrate, which is characterized in that different kinds of liquid phase epitaxial growth solutions are injected one after another into solution receptacle, the bottom of which is open to the substrate surface, and each of the preceding one of the epitaxial growth solutions is expelled from the solution receptacle by each succeeding one of the epitaxial growth solutions for interchange between both solutions and thereafter each succeeding solution is epitaxially grown on the preceding one.
    Type: Grant
    Filed: December 11, 1975
    Date of Patent: March 22, 1977
    Assignee: Nippon Telegraph and Telephone Public Corporation
    Inventor: Yoshiji Horikoshi