Patents by Inventor Keiichi Higeta

Keiichi Higeta 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: 5898636
    Abstract: A semiconductor integrated circuit device having a memory portion and a logic circuit portion formed with a same semiconductor substrate comprising a first logic circuit block, a second logic circuit block disposed in an area different from an area in which the first logic circuit block is disposed, and a pair of memory blocks oppositely disposed so that the second logic circuit block comes in between. Data stored in the pair of memory blocks are transmitted to the second logic circuit block for processing via a memory peripheral circuit provided on the second logic circuit block. A result of the data processing is transmitted to the first logic circuit block or an external device via an input/output circuit provided in the second logic circuit block.
    Type: Grant
    Filed: June 7, 1994
    Date of Patent: April 27, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Satoru Isomura, Atsushi Shimizu, Keiichi Higeta, Tohru Kobayashi, Takeo Yamada, Yuko Ito, Kengo Miyazawa, Kunihiko Yamaguchi
  • Patent number: 5583817
    Abstract: Read signals to be outputted in the unit of bits from a packaged RAM are received to produce complementary output signals, and these output signals and the non-inverted and inverted signals of expected values are individually inputted to two logic circuits, so that the outputs of the logic circuits are compared by a coincidence/incoincidence circuit to produce a decision output.
    Type: Grant
    Filed: February 2, 1995
    Date of Patent: December 10, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Etsuko Kawaguchi, Keiichi Higeta, Yasuhiro Fujimura, Kunihiko Yamaguchi
  • Patent number: 5428312
    Abstract: A semiconductor integrated circuit device has a circuit construction which is devised with an output circuit for feeding an output current to an operating supply voltage in response to an output signal of a current switch circuit responding to an input signal. A constant current element for producing the operating current of the current switch circuit is fed with a constant voltage through a resistance element. A capacitor is coupled between the input of the constant current element and the operating supply voltage so that it constructs a time constant circuit together with the resistance element. The time constant circuit has a time constant set longer than the period of the output signal of the output circuit.
    Type: Grant
    Filed: May 7, 1993
    Date of Patent: June 27, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Keiichi Higeta, Satoru Isomura, Kazuhiro Akimoto
  • Patent number: 5351211
    Abstract: An integrated circuit including latch circuits disposed on the input and output sides of an object circuit the delay time of which is to be measured, respectively, and a variable delay circuit capable of arbitrarily delaying a timing signal supplied from outside or a timing signal generated inside the integrated circuit by an instruction from outside. The timing signal and a delay signal obtained by delaying the input signal by the variable delay circuit are supplied as clock signals to the latch circuits, and the signal passing through the variable delay circuit is fed back to the input side so as to constitute an oscillation circuit, the oscillation signal of which can be outputted to outside. A signal delayed by a desired time can be automatically generated inside the semiconductor integrated circuit on the basis of this timing signal.
    Type: Grant
    Filed: July 23, 1993
    Date of Patent: September 27, 1994
    Assignee: Hitachi, Ltd.
    Inventors: Keiichi Higeta, Sohei Omori, Yasuhiro Fujimura, Etsuko Iwamoto, Akihisa Uchida
  • Patent number: 5214302
    Abstract: A semiconductor integrated circuit device having a structure in which each of the following regions, that is, a first region for forming the base and emitter regions of each of the bipolar transistors, a second region for forming the collector lead-out region of the bipolar transistor, and a third region for forming each of the MISFETs, is projected from the main surface of a semiconductor substrate, whereby it is possible to effect isolation between the MISFETs and between these MISFETs and the bipolar transistors with the same isolation structure and in the same manufacturing step as those for the isolation between the bipolar transistors. In this device, furthermore, the base region of the bipolar transistor is electrically and self-alignedly connected to a base electrode which is formed over the main surface so as to surround the emitter region.
    Type: Grant
    Filed: December 13, 1991
    Date of Patent: May 25, 1993
    Assignee: Hitachi, Ltd.
    Inventors: Akihisa Uchida, Keiichi Higeta, Nobuo Tamba, Masanori Odaka, Katsumi Ogiue
  • Patent number: 5128740
    Abstract: This invention relates to a semiconductor integrated circuit device including highly self-aligned bipolar transistors. The semiconductor integrated circuit device a semiconductor body at least a first protruding portion and a hollow portion, disposed as a trench. The hollow portion being adjacent to the first protruding portion and being lower than an upper surface of the first protruding portion and including an isolation groove which is formed along a side surface of the protruding portion and in self-alignment with a peripheral edge portion of the upper surface of the first protruding portion.
    Type: Grant
    Filed: November 17, 1989
    Date of Patent: July 7, 1992
    Assignee: Hitachi, Ltd.
    Inventors: Akihisa Uchida, Katsumi Ogiue, Toru Koizumi, Keiichi Higeta
  • Patent number: 5029127
    Abstract: There is implemented memory cells and corresponding signal lines associated therewith in bipolar type static random access memories employing wirings of multi-layer construction for transmitting a common signal therethrough such as with respect to the individual word lines. The word lines implemented are formed from at least a pair of stacked conductive layers and which layers have interposed therebetween an insulating film. The pair of layers form a pair of wiring lines wherein together they form a work line and wherein the wiring lines are, furthermore, interconnected at predetermined intervals along the lengths thereof. This leads to the ability to decrease the chip size of semiconductor integrated circuits noting that a decrease in the voltage drop of a signal line results, and to prevent electromigration in the signal (wiring) lines.
    Type: Grant
    Filed: May 15, 1990
    Date of Patent: July 2, 1991
    Assignee: Hitachi, Ltd.
    Inventors: Akihisa Uchida, Ichiro Mitamura, Keiichi Higeta
  • Patent number: 4926378
    Abstract: There is implemented memory cells and corresponding signal lines associated therewith in bipolar type static random access memories employing wirings of multi-layer construction for transmitting a common signal therethrough such as with respect to the individual word lines. The word lines implemented are formed from at least a pair of stacked conductive layers of a material whose principal component is aluminum and which layers have interposed therebetween an insulating film. The pair of layers form a pair of wiring lines corresponding together to a word line and wherein the wiring lines are, furthermore, interconnected at predetermined intervals along the lengths thereof. This leads to the ability to decrease the chip size of semiconductor integrated circuits noting that a decrease in the voltage drop of a signal line results, and to prevent electromigration in the signal (wiring) lines.
    Type: Grant
    Filed: February 25, 1988
    Date of Patent: May 15, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Akihisa Uchida, Ichiro Mitamura, Keiichi Higeta
  • Patent number: 4809052
    Abstract: A semiconductor memory device is provided such as the type having flip-flop memory cells each including two bipolar transistors in cross connection with each other. In certain embodiments, at least a part of a Schottky barrier diode or capacitor in the memory cell is formed under a digit line. This memory device is greatly reduced in its required area, and the Schottky barrier diode and capacitor are negligibly influenced by the digit line. In other embodiments, it is arranged to provide different electrodes for the Schottky barrier diode and the capacitor to optimize construction in a minimized space.
    Type: Grant
    Filed: May 7, 1986
    Date of Patent: February 28, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Yasushiro Nishioka, Takeo Shiba, Hiroshi Shinriki, Kiichiro Mukai, Akihisa Uchida, Ichiro Mitamura, Keiichi Higeta, Katsumi Ogiue, Kunihiko Yamaguchi, Noriyuki Sakuma