Patents by Inventor Tadamichi Asai

Tadamichi Asai 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: 5204166
    Abstract: The present invention relates to a thick film resistor material which is suitable especially for thick film hybrid IC having conductor, resistor, semiconductor element and the like in which Cu is used as the conductor and furthermore, a thick film resistor composition which can be fired in a reducing atmosphere. The present invention further relates to a thick film hybrid IC using the thick film resistor composition as a resistor and a method for making it.
    Type: Grant
    Filed: February 25, 1991
    Date of Patent: April 20, 1993
    Assignees: Hitachi, Ltd., Hitachi Chemical Company, Ltd.
    Inventors: Osamu Ito, Tadamichi Asai, Toshio Ogawa, Noritaka Kamimura, Yoshishige Endou, Takao Kobayashi, Hiromi Isomae, Masaki Kamiakutsu, Michio Otani, Katsuo Ebisawa
  • Patent number: 5196915
    Abstract: In a semiconductor device such as hybrid IC, thermal heads, etc., a thick film resistor of the semiconductor device contains a boride particle of a metal dispersed in a glass matrix, the particle having a particles size of 0.005 to 0.1 .mu.m. Generation of a thermal stress can be suppressed and the electroconductive particles themselves form isotropic electroconductive passages by such dispersion, and the semiconductor devices can have a distinguished electroconductivity. Preferable boride of a metal is LaB.sub.6, which gives distinguished resistor characteristics.
    Type: Grant
    Filed: November 17, 1989
    Date of Patent: March 23, 1993
    Assignees: Hitachi, Ltd., Hitachi Chemical Company, Ltd.
    Inventors: Osamu Ito, Tadamichi Asai, Toshio Ogawa, Mitsuru Hasegawa, Akira Ikegami, Yoshishige Endoh, Michio Ootani, Katsuo Ebisawa
  • Patent number: 5016089
    Abstract: A substrate for hybrid IC which comprises a substrate, a thick film resistor containing glass, formed on the substrate, and a thick film conductor at the terminal of the thick film resistor, where a means for preventing diffusion of the glass from the thick film resistor into the thick film conductor is provided between the thick film resistor and the thick film conductor has a stable resistance as a thick film microresistor and is applied to various uses such as cellular radio communication system.
    Type: Grant
    Filed: January 4, 1989
    Date of Patent: May 14, 1991
    Assignee: Hitachi, Ltd.
    Inventors: Mituru Fujii, Tadamichi Asai, Toshio Ogawa, Osamu Ito, Akira Ikegami, Mitsuru Hasegawa, Takao Kobayashi, Teizo Tamura
  • Patent number: 4873022
    Abstract: The present invention provides an electronic circuit component having a ceramic base and more particularly to a conductive paste for circuit film and an electronic circuit component having a copper film circuit of 10 .mu.m of less in film thickness formed from said conductive paste and a method for making the electronic circuit component.The characteristic of the present invention resides in a conductive paste comprising 100 parts by weight of copper powder of 1 .mu.m or less in average particle size, 0.01-4 parts by weight of at least one of S, Te and Se and 1-10 parts by weight of a frit glass as a binder.Further, there is provided an electronic circuit component having a copper film circuit containing 0.005-2 parts by weight of at least one of S, Te and Se and an effective amount of a glass as a binder for 100 parts by weight of copper which is produced by forming a circuit pattern of said conductive paste on an insulating base by flexo-printing method or the like and then firing the pattern.
    Type: Grant
    Filed: December 30, 1987
    Date of Patent: October 10, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Toshio Ogawa, Mituru Fujii, Tadamichi Asai, Akira Ikegami, Hiroshi Ohtsu, Kazuhiko Ato
  • Patent number: 4585706
    Abstract: A semi-conductor device comprising sintered aluminum nitride having a high thermal conductivity, which comprises at least 65% by weight of aluminum nitride, and at least one of beryllium, a beryllium compound, lithium and a lithium compound.
    Type: Grant
    Filed: August 26, 1985
    Date of Patent: April 29, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Yukio Takeda, Satoru Ogihara, Mitsuru Ura, Kousuke Nakamura, Tadamichi Asai, Tokio Ohkoshi, Yasuo Matsushita, Kunihiro Maeda
  • Patent number: 4540673
    Abstract: Sintered aluminum nitride having a high thermal conductivity, which comprises at least 65% by weight of aluminum nitride, and at least one of beryllium, a beryllium compound, lithium and a lithium compound, and a semi-conductor device using the same.
    Type: Grant
    Filed: April 29, 1982
    Date of Patent: September 10, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Yukio Takeda, Satoru Ogihara, Mitsuru Ura, Kousuke Nakamura, Tadamichi Asai, Tokio Ohkoshi, Yasuo Matsushita, Kunihiro Maeda
  • Patent number: 4345179
    Abstract: A resistor spark plug having, between a terminal screw and a center electrode, electrical conductive glass seals and a resistor glass seal therebetween, said electrical conductive glass seals containing carbon, one or more metals and glass and said resistor glass seal containing carbon, silicon carbide, glass, boron carbide or titanium carbide, and if desired a filler, has a small voltage coefficient of resistance and stable properties and is effective for reducing noise from an ignition system.
    Type: Grant
    Filed: July 10, 1980
    Date of Patent: August 17, 1982
    Assignee: Hitachi, Ltd.
    Inventors: Tadamichi Asai, Kousuke Nakamura