Patents by Inventor Katsuo Yuhara

Katsuo Yuhara 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: 6969649
    Abstract: A DRAM has, in one embodiment, a plurality of word lines each having its upper and side surfaces covered with a first insulating film, a plurality of bit lines each being provided so as to be insulated from and transverse to the word lines and being covered with a second insulating film, and a plurality of memory cells each provided at an intersection between one word line and one bit line and including a capacitor and a memory cell selection transistor, in which contact holes for connection between semiconductor regions and capacitors and between semiconductor regions and bit lines are formed in self-alignment and the second insulating film is made of a material having a permittivity smaller than that of the first insulating film.
    Type: Grant
    Filed: March 29, 2004
    Date of Patent: November 29, 2005
    Assignees: Hitachi, Ltd., Texas Instruments Incorporated
    Inventors: Toshihiro Sekiguchi, Yoshitaka Tadaki, Keizo Kawakita, Hideo Aoki, Toshikazu Kumai, Kazuhiko Saito, Michio Nishimura, Michio Tanaka, Katsuo Yuhara, Shinya Nishio, Toshiyuki Kaeriyama, Songsu Cho
  • Publication number: 20040179389
    Abstract: A DRAM has, in one embodiment, a plurality of word lines each having its upper and side surfaces covered with a first insulating film, a plurality of bit lines each being provided so as to be insulated from and transverse to the word lines and being covered with a second insulating film, and a plurality of memory cells each provided at an intersection between one word line and one bit line and including a capacitor and a memory cell selection transistor, in which contact holes for connection between semiconductor regions and capacitors and between semiconductor regions and bit lines are formed in self-alignment and the second insulating film is made of a material having a permittivity smaller than that of the first insulating film.
    Type: Application
    Filed: March 29, 2004
    Publication date: September 16, 2004
    Inventors: Toshihiro Sekiguchi, Yoshitaka Tadaki, Keizo Kawakita, Hideo Aoki, Toshikazu Kumai, Kazuhiko Saito, Michio Nishimura, Michio Tanaka, Katsuo Yuhara, Shinya Nishio, Toshiyuki Kaeriyama, Songsu Cho
  • Patent number: 6753219
    Abstract: A DRAM has, in one embodiment, a plurality of word lines each having its upper and side surfaces covered with a first insulating film, a plurality of bit lines each being provided so as to be insulated from and transverse to the word lines and being covered with a second insulating film, and a plurality of memory cells each provided at an intersection between one word line and one bit line and including a capacitor and a memory cell selection transistor, in which contact holes for connection between semiconductor regions and capacitors and between semiconductor regions and bit lines are formed in self-alignment and the second insulating film is made of a material having a permittivity smaller than that of the first insulating film.
    Type: Grant
    Filed: August 23, 2002
    Date of Patent: June 22, 2004
    Assignees: Hitachi, Ltd., Texas Instruments, Inc.
    Inventors: Toshihiro Sekiguchi, Yoshitaka Tadaki, Keizo Kawakita, Hideo Aoki, Toshikazu Kumai, Kazuhiko Saito, Michio Nishimura, Michio Tanaka, Katsuo Yuhara, Shinya Nishio, Toshiyuki Kaeriyama, Songsu Cho
  • Publication number: 20020192905
    Abstract: A DRAM has, in one embodiment, a plurality of word lines each having its upper and side surfaces covered with a first insulating film, a plurality of bit lines each being provided so as to be insulated from and transverse to the word lines and being covered with a second insulating film, and a plurality of memory cells each provided at an intersection between one word line and one bit line and including a capacitor and a memory cell selection transistor, in which contact holes for connection between semiconductor regions and capacitors and between semiconductor regions and bit lines are formed in self-alignment and the second insulating film is made of a material having a permittivity smaller than that of the first insulating film.
    Type: Application
    Filed: August 23, 2002
    Publication date: December 19, 2002
    Inventors: Toshihiro Sekiguchi, Yoshitaka Tadaki, Keizo Kawakita, Hideo Aoki, Toshikazu Kumai, Kazuhiko Saito, Michio Nishimura, Michio Tanaka, Katsuo Yuhara, Shinya Nishio, Toshiyuki Kaeriyama, Songsu Cho
  • Patent number: 6060352
    Abstract: A method for fabricating DRAMs each having a COB structure, and the semiconductor device formed by this method, are provided. In one embodiment, the word line and/or bit line is covered with an insulating film having a comparatively small etching rate. Contact holes are formed while being defined by those insulating films in self-alignment.
    Type: Grant
    Filed: January 28, 1998
    Date of Patent: May 9, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Toshihiro Sekiguchi, Hideo Aoki, Yoshitaka Tadaki, Keizo Kawakita, Jun Murata, Katsuo Yuhara, Michio Nishimura, Kazuhiko Saitoh, Minoru Ohtsuka, Masayuki Yasuda, Toshiyuki Kaeriyama, Songsu Cho
  • Patent number: 6023084
    Abstract: A semiconductor memory device has a semiconductor substrate, and memory cells provided at intersections between word line conductors and bit line conductors. Adjacent two memory cells for each bit line conductor form a memory cell pair unit structure, in which first semiconductor regions of the transistors of the adjacent two memory cells are united at their boundary into a single region and are connected to one of the bit line conductors via a bit line connection conductor, the gate electrodes of the transistors of the adjacent two memory cells are connected to word line conductors adjacent to each other, respectively, and the second semiconductor regions of the transistors of the adjacent two memory cells are connected to the respective information storage capacitors.
    Type: Grant
    Filed: October 19, 1998
    Date of Patent: February 8, 2000
    Assignees: Hitachi, Ltd., Texas Instruments Inc.
    Inventors: Yoshitaka Tadaki, Jun Murata, Toshihiro Sekiguchi, Hideo Aoki, Keizo Kawakita, Hiroyuki Uchiyama, Michio Nishimura, Michio Tanaka, Yuji Ezaki, Kazuhiko Saitoh, Katsuo Yuhara, Songsu Cho
  • Patent number: 5937290
    Abstract: In an embodiment of a method of manufacturing semiconductor integrated circuit devices according to the present invention, word lines are provided in a straight form, which serve as gate electrodes of two selecting MOSFETs formed symmetrical about a center portion of an active region surrounded by a LOCOS oxide film on a semiconductor substrate, and bit lines have straight segments and protruding segments. Each protruding segment is formed to protrude from the bit line and is connected through a first contact hole to a first semiconductor region formed at the center portion of the active region. The straight line segments and the protruding segments are formed separately by two separate exposure steps.
    Type: Grant
    Filed: May 27, 1997
    Date of Patent: August 10, 1999
    Assignees: Hitachi, Ltd., Texas Instruments Incorporated
    Inventors: Toshihiro Sekiguchi, Yoshitaka Tadaki, Keizo Kawakita, Katsuo Yuhara, Kazuhiko Saito, Shinya Nishio, Michio Tanaka, Michio Nishimura, Toshiyuki Kaeriyama, Songsu Cho
  • Patent number: 5933724
    Abstract: A phase shifting mask is used for manufacturing a semiconductor integrated circuit device including a conductor pattern in which the line width of patterned conductor strips or the space between patterned conductor strips is not constant. For main transparent areas in the mask corresponding to the conductor pattern, auxiliary pattern segments are provided for compensating changes in the phase distribution of transmitted light caused by changes of the line width or the space. Alternately, the spaces between the conductor strips are adjusted to suppress the changes in the phase distribution of transmitted light. Whether the auxiliary pattern segments should have the phase shifting function is determined depending upon the disposition of the main transparent areas.
    Type: Grant
    Filed: August 26, 1996
    Date of Patent: August 3, 1999
    Assignees: Hitachi, Ltd., Texas Instruments
    Inventors: Toshihiro Sekiguchi, Yoshitaka Tadaki, Keizo Kawakita, Jun Murata, Katsuo Yuhara, Toshikazu Kumai, Michio Tanaka, Michio Nishimura, Kazuhiko Saitoh, Takatoshi Kakizaki, Takeshi Sakai, Toshiyuki Kaeriyama, Songsu Cho
  • Patent number: 5933726
    Abstract: A semiconductor device, such as a dynamic RAM, and method of making it. A number of stacked cell capacitors are placed at a prescribed spacing in an alignment direction on top of a p.sup.- -type silicon substrate (1). Each capacitor has a nearly perpendicular cylindrical lower electrode (cylindrical polysilicon layer (96)), a dielectric film (silicon nitride film (77)), and upper electrode (plate electrode (78) made of polysilicon). The spacing in the alignment direction is smaller than the inner diameter of the lower electrode.
    Type: Grant
    Filed: August 27, 1996
    Date of Patent: August 3, 1999
    Assignee: Texas Instruments Incorporated
    Inventors: Michio Nishimura, Kazuhiko Saitoh, Masayuki Yasuda, Takashi Hayakawa, Michio Tanaka, Yuji Ezaki, Katsuo Yuhara, Minoru Ohtsuka, Toshikazu Kumai, Songsu Cho, Toshiyuki Kaeriyama, Keizo Kawakita, Toshihiro Sekiguchi, Yoshitaka Tadaki, Jun Murata, Hideo Aoki, Akihiko Konno, Kiyomi Katsuyama, Takafumi Tokunaga, Yoshimi Torii
  • Patent number: 5831300
    Abstract: A semiconductor memory device has a semiconductor substrate, word line conductors and bit line conductors, and memory cells provided at intersections between the word line conductors and bit line conductors. Adjacent two memory cells for each bit line conductor form a memory cell pair unit structure, in which first semiconductor regions of the transistors of the adjacent two memory cells are united at their boundary into a single region and are connected to one of the bit line conductors via a bit line connection conductor, the gate electrodes of the transistors of the adjacent two memory cells are connected to word line conductors adjacent to each other, respectively, the second semiconductor regions of the transistors of the adjacent two memory cells are connected to the respective information storage capacitors.
    Type: Grant
    Filed: October 16, 1996
    Date of Patent: November 3, 1998
    Assignees: Hitachi, Ltd., Texas Instruments Incorporated
    Inventors: Yoshitaka Tadaki, Jun Murata, Toshihiro Sekiguchi, Hideo Aoki, Keizo Kawakita, Hiroyuki Uchiyama, Michio Nishimura, Michio Tanaka, Yuji Ezaki, Kazuhiko Saitoh, Katsuo Yuhara, Songsu Cho
  • Patent number: 5804479
    Abstract: The etch-back amount of a silicon oxide film of a memory array which is a higher altitude portion is increased when etching back and flattening the silicon oxide film by arranging a first-layer wiring on a BPSG film covering an upper electrode of an information-storing capacitative element only in a peripheral circuit but not arranging it in the memory array.Thus, a DRAM having a stacked capacitor structure is obtained such that the level difference between the memory array and peripheral circuit is decreased, and the formation of wiring and connection holes are easy.
    Type: Grant
    Filed: August 9, 1996
    Date of Patent: September 8, 1998
    Assignees: Hitachi, Ltd., Texas Instruments Inc.
    Inventors: Hideo Aoki, Jun Murata, Yoshitaka Tadaki, Toshihiro Sekiguchi, Keizo Kawakita, Takashi Hayakawa, Katsutoshi Matsunaga, Kazuhiko Saitoh, Michio Nishimura, Minoru Ohtsuka, Katsuo Yuhara, Michio Tanaka, Yuji Ezaki, Toshiyuki Kaeriyama, SongSu Cho
  • Patent number: 5732009
    Abstract: A DRAM has memory cells provided at crossing points between word line conductors and bit line conductors. Each memory cell has a cell selection transistor and an information storage capacitor arranged over the bit line conductors. Unit active regions are defined in a main surface of a semiconductor substrate by a field isolation pattern. The field isolation pattern has a controlled length of extension of bird's beaks so that channel formation regions in each unit active region has almost no stepped portion to provide the cell selection transistors with a stabilized threshold voltage.
    Type: Grant
    Filed: July 22, 1996
    Date of Patent: March 24, 1998
    Assignees: Hitachi, Ltd., Texas Instruments Incorporated
    Inventors: Yoshitaka Tadaki, Jun Murata, Katsuo Yuhara, Yuji Ezaki, Michio Tanaka, Michio Nishimura, Kazuhiko Saitoh, Takatoshi Kakizaki, Shinya Nishio, Takeshi Sakai, Songsu Cho
  • Patent number: 5578849
    Abstract: A memory device has a semiconductor substrate, and memory cells provided at intersections between word line conductors and bit line conductors. Each memory cell has a switching transistor and an information storage capacitor. Adjacent two memory cells for each bit line conductor form a memory cell pair unit structure, in which first semiconductor regions of the transistors of the adjacent two memory cells are united at their boundary into a single region and are connected to one of the bit line conductors via a bit line connection conductor, the gate electrodes of the transistors of the adjacent two memory cells are connected to word line conductors adjacent to each other, respectively, the second semiconductor regions of the transistors of the adjacent two memory cells are connected to the respective information storage capacitors.
    Type: Grant
    Filed: November 16, 1994
    Date of Patent: November 26, 1996
    Assignees: Hitachi, Ltd., Texas Instruments, Inc.
    Inventors: Yoshitaka Tadaki, Jun Murata, Toshihiro Sekiguchi, Hideo Aoki, Keizo Kawakita, Hiroyuki Uchiyama, Michio Nishimura, Michio Tanaka, Yuji Ezaki, Kazuhiko Saitoh, Katsuo Yuhara, Songsu Cho
  • Patent number: 4543441
    Abstract: A solar battery has a pair of opposed light incident transparent electroconductive and back electrodes sandwiching amorphous silicon layers formed on a substrate with at least a major surface of the back electrode surface being in contact with an organic resin layer and being made of a compound of a transition metal and silicon, a compound of a transition metal and nitrogen, or a compound of a transition metal and carbon. Excellent corrosion resistance of the back electrode is obtained and the battery has high performance and high reliability.
    Type: Grant
    Filed: February 13, 1984
    Date of Patent: September 24, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Masaharu Kumada, Hideo Tanabe, Katsuo Yuhara, Akira Misumi, Hiroshi Kawasaki