Patents by Inventor Kazumi Iwadate

Kazumi Iwadate 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: 4820609
    Abstract: A highly sensitive positive resist mixture which comprises a resist having a carboxyl group at the side chain and which is decomposable by high energy rays constituted by a polymer having the formula I ##STR1## where R.sub.1, R.sub.2, . . . R.sub.n represent alkyl groups, halogenated alkyl groups, or aryl groups having five or fewer carbon atoms, or --COORa or --CORb (where Ra and Rb are alkyl groups or halogenated alkyl or aryl groups having five or fewer carbon atoms), and when ##EQU1## m.sub.c /M is in the range of 0.01 to 1.0 and m.sub.1 /M, m.sub.2 /M, . . . m.sub.n /M are respectively in the range of 0.99 to 0, and an additive selected from the group consisting of oxides, halides and organic acid salts of bivalent metals.
    Type: Grant
    Filed: June 25, 1987
    Date of Patent: April 11, 1989
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Kazumi Iwadate, Katsuhiro Harada
  • Patent number: 4808829
    Abstract: A mark position detection system used in a charged particle beam apparatus and including detection circuit for detecting a reflected electron generated at a mark when the mark is scanned with a charged particle beam, to obtain a mark signal, and signal processing circuit for comparing the mark signal from the detection circuit with a predetermined threshold level to find the position of the charged particle beam at a time the mark signal traverses the threshold level, thereby detecting the position of a mark edge, is disclosed in which, when the mark signal traverses the threshold level and has a peak value exceeding a predetermined value, it is determined by the signal processing circuit that the position of the charged particle beam at a time point at which the mark signal traverses the threshold level is the position of the mark.
    Type: Grant
    Filed: June 17, 1987
    Date of Patent: February 28, 1989
    Assignees: Hitachi Ltd., Nippon Telegraph and Telephone Corp.
    Inventors: Masahide Okumura, Takashi Matsuzaka, Genya Matsuoka, Kazumi Iwadate, Tadahito Matsuda, Ryoichi Yamaguchi
  • Patent number: 4699870
    Abstract: In a fine pattern forming method for use in the manufacture of semiconductor integrated circuits, optical integrated circuits, Josephson elements, and so forth, a positive resist mixture is used which is composed of a resist having a carboxyl group in the side chain and an additive which is an oxide, halide, or organic acid salt of a bivalent metal and which, when heated, forms Ionomer to produce thermal crosslinks. The positive resist mixture is developed using a developer having carboxylic acid mixed in an organic solvent, thereby permitting the formation of an ultra-fine and high precision pattern.
    Type: Grant
    Filed: March 19, 1986
    Date of Patent: October 13, 1987
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Kazumi Iwadate, Katsuhiro Harada
  • Patent number: 4692579
    Abstract: An electron beam lithography apparatus comprises: a spot electron beam generator; device for exposing a desired pattern onto a wafer using the spot beam; device for dividing the pattern into small regions; and device for designating an origin of the small region and also digitally scanning the portion inside the small region by a fixed correction amount by use of the spot beam, and thereby to reduce the settling time of the D/A converter in association with the digital scanning.
    Type: Grant
    Filed: May 17, 1985
    Date of Patent: September 8, 1987
    Assignees: Hitachi, Ltd., Nippon Telegraph & Telephone Corporation
    Inventors: Norio Saitou, Susumu Ozasa, Masahide Okumura, Mitsuo Ooyama, Tsutomu Komoda, Katsuhiro Harada, Minpei Fujinami, Kazumi Iwadate