Patents by Inventor Akihisa Yoshida

Akihisa Yoshida 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: 5976919
    Abstract: A large area semiconductor element can be manufactured with high productivity, which has low electric resistance at the boundary face of a metal and a semiconductor and has excellent characteristics and reliability. A manufacturing apparatus comprises an ion irradiation means for simultaneously irradiating hydrogen ions and ions containing an element serving as a dopant of a semiconductor to a semiconductor film or a substrate in an atmosphere under reduced pressure, and a film forming means which forms a thin film or a heat treatment means which conducts a heat treatment without exposing a sample to an air. When a sample having an a-Si:H thin film is brought into a sample preparation chamber by opening a gate valve, the chamber is exhausted to have the inside pressure of 10.sup.2 to 10.sup.-3 Pa. Then, the sample is forwarded to an ion irradiation chamber from the sample preparation chamber via an intermediate chamber of which the pressure is maintained in the range of 10.sup.-3 to 10.sup.
    Type: Grant
    Filed: August 1, 1997
    Date of Patent: November 2, 1999
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Takashi Hirao, Akihisa Yoshida, Masatoshi Kitagawa
  • Patent number: 5814194
    Abstract: Cluster particles including a plurality of molecules or atoms are prepared by a gas cluster method, are accelerated, and are then irradiated onto a diamond in a low pressure atmosphere, so that the unevenness surfaces of the diamond are smoothed with no damages in the diamond. The cluster particles are prepared by the steps of forming, ionizing, mass-separating, and accelerating cluster particles. The cluster particles with a certain energy are irradiated onto the surface of the diamond. Irradiated cluster particles collide with the surface of the diamond, and then break apart into each molecule or atom while changing momentum (direction and speed) or energy. Thus, the surface of the diamond is efficiently smoothed and etched.
    Type: Grant
    Filed: October 12, 1995
    Date of Patent: September 29, 1998
    Assignees: Matsushita Electric Industrial Co., Ltd, Research Development Corporation of Japan
    Inventors: Masahiro Deguchi, Akihisa Yoshida, Makoto Kitabatake, Takashi Hirao
  • Patent number: 5766342
    Abstract: The method for forming a silicon film of this invention includes the steps of introducing a compound containing silicon and chlorine and being in a liquid form under normal pressure and at an ordinary temperature into a reaction chamber, and spraying the compound in the liquid form in a fine particle state to a surface of a substrate supported in the reaction chamber, and decomposing the compound in the fine particle state by energy applied from outside of the reaction chamber, and depositing a silicon film on the substrate supported in the reaction chamber.
    Type: Grant
    Filed: October 17, 1995
    Date of Patent: June 16, 1998
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Munehiro Shibuya, Masatoshi Kitagawa, Yuji Mukai, Takashi Hirao, Akihisa Yoshida
  • Patent number: 5141885
    Abstract: A method of fabricating a thin film transistor on an insulating substrate such as quartz or glass without defect in the channel region in semiconductor thin layer, or at the boundary between the semiconductor thin layer and gate insulation layer, but with high mobility and high integration. For that purpose, ions produced by the discharge-decomposition of a hydride gas including dopant are accelerated and implanted into the semiconductor thin layer, wherein the protecting insulation layer for protection of the channel region is of a thickness larger than the projected range of the hydrogen ion.
    Type: Grant
    Filed: June 3, 1991
    Date of Patent: August 25, 1992
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Akihisa Yoshida, Masatoshi Kitagawa, Takashi Hirao
  • Patent number: 4859908
    Abstract: A plasma processing apparatus performs various plasma processings of a substrate having a large area in a semiconductor element manufacturing process, by using highly excited plasma generated at a low pressure under the application of RF power and a magnetic field. In this plasma processing apparatus, a gas is introduced into a vacuum chamber to be used as an ion source, RF power is applied to two electrodes having respective surfaces opposite to each other through the gas to thereby generate the plasma in the vacuum chamber, and a magnetic field is applied to the plasma from a magnetic field source arranged at a predetermined position. The intensity of the applied magnetic field is set to be 1.5 times or more the magnetic field intensity which causes electron cyclotron resonance to occur at the frequency f of the applied RF power. Particularly, when the frequency f of the RF power is 13.56 MHz, the magnetic field intensity is selected to be in the range from 25 gausses to 35 gausses.
    Type: Grant
    Filed: September 23, 1987
    Date of Patent: August 22, 1989
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Akihisa Yoshida, Kentaro Setsune, Takashi Hirao