Patents by Inventor Tomoe Kurosawa

Tomoe Kurosawa 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: 5133825
    Abstract: An apparatus for generating plasma by making use of electron cyclotron resonance employs permanent magnets for forming magnetic fields, and the permanent magnets are arranged in such a manner as to form stronger magnetic fields in peripheral portion of a plasma chamber than in a central portion of the same. in addition, a cross-sectional area of the plasma chamber is gradually increased. Furthermore, electrons are introduced into an additional plasma chamber in which an electric field is not applied so as to generate low-temperature plasma.
    Type: Grant
    Filed: April 7, 1988
    Date of Patent: July 28, 1992
    Assignee: Hi Tachi, Ltd.
    Inventors: Yoshimi Hakamata, Ken-ichi Natsui, Yukio Kurosawa, Tadashi Sato, Hiroaki Kojima, Yasunori Ohno, Tomoe Kurosawa
  • Patent number: 4851668
    Abstract: An ion source application device comprising a gas tight plasma formation chamber sustaining a plasma produced by high frequency discharge, a high frequency coil producing the high frequency discharge, and means for extracting an ion beam from the plasma thus produced, characterized in that it comprises further an electron beam generator or a laser light generator as means for obtaining electrons serving as seeds for starting the high frequency discharge.
    Type: Grant
    Filed: April 6, 1987
    Date of Patent: July 25, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Tasunori Ohno, Tomoe Kurosawa, Tadashi Sato, Yukio Kurosawa, Yoshimi Hakamata
  • Patent number: 4847476
    Abstract: An ion source device comprises a plasma generating vessel for generating plasma therein, a plurality of magnets arranged on an outer periphery of the plasma generating vessel to establish a cusp field in the plasma generating vessel, means for supplying a power to generate the plasma in the plasma generating vessel, and an anode electrode arranged on an inner wall of the plasma generating vessel and adapted to be heated by electrons emitted from the plasma and maintain the heat.
    Type: Grant
    Filed: December 17, 1986
    Date of Patent: July 11, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Tadashi Sato, Yasunori Ohno, Tomoe Kurosawa, Nobuya Sekimoto, Yoshimi Hakamata, Yukio Kurosawa, Kunio Hirasawa
  • Patent number: 4767931
    Abstract: A thin film manufacturing and processing apparatus by using an ion beam comprises a plasma producing vessel for producing therein a plasma by ionizing a neutral gas, an electrode assembly for extracting ions in the form of an ion beam from the plasma, a vacuum container accomodating therein a target to be worked through irradiation of the ion beam, and permanent magnets disposed on the outer periphery of the plasma generating vessel which is formed of a nonmagnetic material and serves as an anode electrode. An ion beam of high uniformity and a large diameter can be obtained to allow manufacture and processing of large scale magnetic thin films and semiconductors with high precision.
    Type: Grant
    Filed: December 17, 1986
    Date of Patent: August 30, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Tadashi Sato, Tomoe Kurosawa, Shigetaka Fujiwara, Masaru Higaki
  • Patent number: 4716491
    Abstract: In a high frequency plasma generation apparatus used in a reactive ion etching apparatus, an ion shower apparatus, a sputter apparatus, etc. for fabricating thin films or semiconductor devices for which a fine patterning process is required, electrical breakdown is apt to be provoked at the surface of a high frequency coil, because the high frequency coil is usually inserted in a plasma. In order to remove this drawback, according to this invention, the high frequency coil is disposed in the plasma production chamber at the neighborhood of the cylindrical side wall, and thus a plasma confinement domain is formed inside of this high frequency coil by use of a magnetic field production device which generates a multi-cusp magnetic field so that the plasma confinement domain is separated from the high frequency coil. In this way, electrical breakdown on the surface of the high frequency coil is prevented and thus the apparatus according to this invention can work stably for a long time.
    Type: Grant
    Filed: December 9, 1985
    Date of Patent: December 29, 1987
    Assignee: Hitachi, Ltd.
    Inventors: Yasunori Ohno, Tomoe Kurosawa, Tadashi Sato, Youichi Ohshita
  • Patent number: 4713585
    Abstract: An ion source for producing an ion beam utilized for fabrication and processing of semiconductors, thin films or the like includes a plasma producing chamber equipped with first magnetic means for limiting a plasma region and a plasma expansion chamber provided in combination with the plasma producing chamber on the side where a beam extracting electrode is disposed. The plasma expansion chamber is provided with second magnet array for confining and holding a plasma region therein which is of a larger area than that of the plasma region formed in the plasma producing chamber.
    Type: Grant
    Filed: September 26, 1986
    Date of Patent: December 15, 1987
    Assignee: Hitachi, Ltd.
    Inventors: Yasunori Ohno, Tomoe Kurosawa, Tadashi Sato, Yukio Kurosawa, Yoshimi Hakamata