Patents by Inventor Koichi Hirata

Koichi Hirata 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: 7109950
    Abstract: A display apparatus in which one of periods of time of a plurality of subfields is sequentially designated within a display period of time of one field, one line is sequentially designated for the purpose of sequentially scanning all lines within the period of time of each subfield, data of one designated line in pixel data of one field stored in a field memory is read, the pixel data of each pixel of one line is individually converted into bit train data showing light emission or non-light emission of each of the plurality of subfields, each bit corresponding to the period of time of the designated subfield in the bit train data of each pixel of one line is generated in parallel, and a display panel is driven in accordance with the parallel output bits, the designated period of time of one subfield, and one designated line.
    Type: Grant
    Filed: May 24, 2002
    Date of Patent: September 19, 2006
    Assignees: Pioneer Corporation, Pioneer Display Products Corporation
    Inventors: Koichi Hirata, Hitoshi Mochizuki
  • Publication number: 20050179106
    Abstract: A Schottky barrier diode has a Schottky electrode formed on an operation region of a GaAs substrate and an ohmic electrode surrounding the Schottky electrode. The ohmic electrode is disposed directly on an impurity-implanted region formed on the substrate. A nitride film insulates the ohmic electrode from a wiring layer connected to the Schottky electrode crossing over the ohmic electrode. The planar configuration of this device does not include the conventional polyimide layer, and thus has a better high frequency characteristics than conventional devices.
    Type: Application
    Filed: April 12, 2005
    Publication date: August 18, 2005
    Applicant: Sanyo Electric Company, Ltd.
    Inventors: Tetsuro Asano, Katsuaki Onoda, Yoshibumi Nakajima, Shigeyuki Murai, Hisaaki Tominaga, Koichi Hirata, Mikito Sakakibara, Hidetoshi Ishihara
  • Patent number: 6897126
    Abstract: In a method of manufacturing a compound semiconductor device, individual chip patterns are projected onto a (1 0 0) surface of a GaAs wafer so that the columns and rows of the chip patterns are aligned in a direction slanting by 45 degrees with respect to a [0 1 1] direction of the GaAs wafer. The wafer is diced along this slanting direction and chipping along the edges of the individual separated chips is greatly reduced.
    Type: Grant
    Filed: July 8, 2002
    Date of Patent: May 24, 2005
    Assignee: Sanyo Electric, Co., Ltd.
    Inventors: Tetsuro Asano, Masahiro Uekawa, Koichi Hirata, Mikita Sakakibara
  • Patent number: 6894371
    Abstract: In a case of a semiconductor chip having an electrode pad to be wire-bonded to a header, securing of a fixing region is difficult since the spread of an Ag paste cannot be controlled, therefore, there has existed a problem such that stable manufacturing could not be carried out. Also, there existed a problem such that realization of stable manufacturing resulted in an excessively large external package form. A projection part is provided in a header, and a fixing region of a bonding wire is secured by arranging a chip at a position shifted in a direction to become distant from the projection part. An electrode pad to be connected to the header is arranged closer to the chip center than the other electrode pads of the identical chip side, and a wire is extended therefrom to the projection part or in the vicinity thereof so as to cross the chip and is fixed. Thereby, downsizing of the package and stable manufacturing are realized.
    Type: Grant
    Filed: February 6, 2003
    Date of Patent: May 17, 2005
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Koichi Hirata, Osamu Isaki, Tsutomu Aono, Toshikazu Hirai, Tetsuro Asano
  • Patent number: 6873828
    Abstract: A compound semiconductor switching device is based on a designing guideline that isolation should be assured by reducing the gate width of switching FET, thereby reducing the capacitance of the FET. Proper isolation between the two signal passes IS obtained with a FET gate width of about 700 ?m or smaller at a signal frequency of about 2.4 GHz or higher, without employing a shunt FET.
    Type: Grant
    Filed: May 15, 2001
    Date of Patent: March 29, 2005
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tetsuro Asano, Takayoshi Higashino, Koichi Hirata
  • Patent number: 6867115
    Abstract: The conventional compound semiconductor switching device is prone to have a large chip size as the gate width needs to be large for achieving a low insertion loss and the separation between the connecting pad and the circuit wiring needs to be larger than 20 ?m for obtaining a proper isolation between them. The overall chip size is reduced, first, by reducing the gate width of the switching FET operating at frequencies above 2.4 GHz to 700 ?m or smaller together with the omission of the shunt FET, and, then, by reducing the separation between the connecting pad and the circuit wiring to 20 ?m or smaller. This reduction of the separation is made possible by the introduction of an insulating film and a impurity region between the outermost portion of the connecting pad and the substrate for preventing the extension of the depletion layer.
    Type: Grant
    Filed: August 5, 2002
    Date of Patent: March 15, 2005
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tetsuro Asano, Toshikazu Hirai, Takayoshi Higashino, Koichi Hirata, Mikito Sakakibara
  • Patent number: 6858489
    Abstract: This invention is directed to the reduction of voltage dependence and thus allows easy design of integrated semiconductor circuits. The device is equipped with a P? type resistance layer, in which a first voltage is applied to one end and a second voltage is applied to the other end and which is formed on the surface of an N-well region on the semiconductor substrate, a thin oxide film on the resistance layer, and a resistance bias electrode which includes the silicon layer formed on the thin oxide film. By adjusting the voltage applied to the resistance bias electrode, the voltage dependence of the resistance of the resistance layer is reduced.
    Type: Grant
    Filed: September 8, 2003
    Date of Patent: February 22, 2005
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Nobuyuki Sekikawa, Koichi Hirata, Masaaki Momen, Shinya Enomoto
  • Patent number: 6840981
    Abstract: A method of producing reduced iron pellets including reducing raw material pellets to obtain reduced iron pellets, and rolling the reduced iron pellets at a temperature ranging between 800 and 1200° C. sufficiently such that the reduced iron pellets undergo sintering.
    Type: Grant
    Filed: May 4, 2001
    Date of Patent: January 11, 2005
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Hironori Fujioka, Hideaki Mizuki, Koichi Hirata, Shigeo Itano, Susumu Kamikawa, Hisao Teramoto, Takashi Yamane, Shigeki Sueda, Tetsumasa Kawamoto
  • Patent number: 6787871
    Abstract: An integrated Schottky barrier diode chip includes a compound semiconductor substrate, a plurality of Schottky barrier diodes formed on the substrate and an insulating region formed on the substrate by an on implantation. The insulating region electrically separates a portion of a diode at a cathode voltage from a portion of the diode at an anode voltage. Because of the absence of a polyimide layer and trench structures, this planar device configuration results in simpler manufacturing method and improved device characteristics.
    Type: Grant
    Filed: October 30, 2002
    Date of Patent: September 7, 2004
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tetsuro Asano, Katsuaki Onoda, Yoshibumi Nakajima, Shigeyuki Murai, Hisaaki Tominaga, Koichi Hirata, Mikito Sakakibara, Hidetoshi Ishihara
  • Patent number: 6777277
    Abstract: A Schottky barrier diode has a Schottky contact region formed in an n epitaxial layer disposed on a GaAs substrate and an ohmic electrode surrounding the Schottky contact region. The ohmic electrode is disposed directly on an impurity-implanted region formed on the substrate. An insulating region is formed through the n epitaxial layer so that an anode bonding pad is isolated form other elements of the device at a cathode voltage. The planar configuration of this device does not include the conventional polyimide layer, and thus has a better high frequency characteristics than conventional devices.
    Type: Grant
    Filed: July 26, 2002
    Date of Patent: August 17, 2004
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tetsuro Asano, Katsuaki Onoda, Yoshibumi Nakajima, Shigeyuki Murai, Hisaaki Tominaga, Koichi Hirata, Mikito Sakakibara, Hidetoshi Ishihara
  • Publication number: 20040113208
    Abstract: A gate electrode includes a first polysilicon film remaining on a first oxide film, a part of a second polysilicon layer 8 superimposed on the polysilicon layer, and a part of the second polysilicon layer partially extending over second gate oxide films. Thus, the thickness of the gate electrode on the first gate oxide film is the same as that of the gate electrode of the prior art, but the film thickness t2 of the gate electrode 10 on the second gate oxide films 6A and 6B is thinner than the thickness t1 of the prior art. Therefore, the height gap h2 between the gate electrode 10 and the N+ type source layer 11 and the height gap h2 between the gate electrode 10 and the N+ type drain layer 12 become smaller compared to those of prior art, leading to the improved flatness of the interlayer oxide film 13.
    Type: Application
    Filed: November 25, 2003
    Publication date: June 17, 2004
    Applicant: Sanyo Electric Co., Ltd.
    Inventors: Nobuyuki Sekikawa, Masaaki Momen, Wataru Andoh, Koichi Hirata
  • Patent number: 6727559
    Abstract: A local oscillation FET has a source connecting pad, a drain connecting pad and a gate connecting pad. The source connecting pad occupies one corner of a substrate, and the drain and gate connecting pads are placed at the neighboring corners so that the three connecting pads form an L shape on the substrate. As a modification to this configuration, another source connecting pad is placed at the remaining corner of the substrate so that the drain and gate connecting pads are shielded from each other by the two source connecting pads. These device configurations contribute to size reduction of the local oscillation FET.
    Type: Grant
    Filed: June 24, 2002
    Date of Patent: April 27, 2004
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tetsuro Asano, Masahiro Uekawa, Koichi Hirata, Mikito Sakakibara
  • Publication number: 20040048434
    Abstract: This invention is directed to the reduction of voltage dependence and thus allows easy design of integrated semiconductor circuits. The device is equipped with a P− type resistance layer, in which a first voltage is applied to one end and a second voltage is applied to the other end and which is formed on the surface of an N-well region on the semiconductor substrate, a thin oxide film on the resistance layer, and a resistance bias electrode which includes the silicon layer formed on the thin oxide film. By adjusting the voltage applied to the resistance bias electrode, the voltage dependence of the resistance of the resistance layer is reduced.
    Type: Application
    Filed: September 8, 2003
    Publication date: March 11, 2004
    Applicant: Sanyo Electric Co. Ltd.
    Inventors: Nobuyuki Sekikawa, Koichi Hirata, Masaaki Momen, Shinya Enomoto
  • Patent number: 6690070
    Abstract: A gate electrode includes a first polysilicon film remaining on a first oxide film, a part of a second polysilicon layer 8 superimposed on the polysilicon layer, and a part of the second polysilicon layer partially extending over second gate oxide films. Thus, the thickness of the gate electrode on the first gate oxide film is the same as that of the gate electrode of the prior art, but the film thickness t2 of the gate electrode 10 on the second gate oxide films 6A and 6B is thinner than the thickness t1 of the prior art. Therefore, the height gap h2 between the gate electrode 10 and the N + type source layer 11 and the height gap h2 between the gate electrode 10 and the N + type drain layer 12 become smaller compared to those of prior art, leading to the improved flatness of the interlayer oxide film 13.
    Type: Grant
    Filed: August 10, 2001
    Date of Patent: February 10, 2004
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Nobuyuki Sekikawa, Masaaki Momen, Wataru Andoh, Koichi Hirata
  • Patent number: 6682968
    Abstract: A Schottky barrier diode has a Schottky electrode formed on an operation region of a GaAs substrate and an ohmic electrode surrounding the Schottky electrode. The ohmic electrode is disposed directly on an impurity-implanted region formed on the substrate. A nitride film insulates the ohmic electrode from a wiring layer connected to the Schottky electrode crossing over the ohmic electrode. The planar configuration of this device does not include the conventional polyimide layer, and thus has a better high frequency characteristics than conventional devices.
    Type: Grant
    Filed: July 26, 2002
    Date of Patent: January 27, 2004
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tetsuro Asano, Katsuaki Onoda, Yoshibumi Nakajima, Shigeyuki Murai, Hisaaki Tominaga, Koichi Hirata, Mikito Sakakibara, Hidetoshi Ishihara
  • Patent number: 6670236
    Abstract: To shorten the production process of the semiconductor device having the capacitance element. The pad oxide film (2) and the first polycrystalline silicon layer (3) are used as a stress buffering material at the time of formation of the element separation oxide film. These are not removed and used as the capacitance insulation film and a portion of the upper electrode of the capacitance element. Thereby, the removing process of the pad•polycrystalline silicon layer, and the dummy oxidation and its removing process in the conventional example, can be omitted and the process can be shortened. Further, a problem of the impurity enhanced oxidation at the time of formation of the capacitance insulation film can be solved.
    Type: Grant
    Filed: August 7, 2001
    Date of Patent: December 30, 2003
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Nobuyuki Sekikawa, Koichi Hirata, Wataru Andoh, Noriyasu Katagiri
  • Patent number: 6627967
    Abstract: A Schottky barrier diode has a Schottky contact region formed in an n epitaxial layer disposed on a GaAs substrate and an ohmic electrode surrounding the Schottky contact region. The ohmic electrode is disposed directly on an impurity-implanted region formed on the substrate. An insulating region is formed through the n epitaxial layer so that an anode bonding pad is isolated form other elements of the device at a cathode voltage. The planar configuration of this device does not include the conventional polyimide layer, and thus has a better high frequency characteristics than conventional devices.
    Type: Grant
    Filed: July 26, 2002
    Date of Patent: September 30, 2003
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tetsuro Asano, Katsuaki Onada, Yoshibumi Nakajima, Shigeyuki Murai, Hisaaki Tominaga, Koichi Hirata, Mikito Sakakibara, Hidetoshi Ishihara
  • Publication number: 20030164536
    Abstract: In a case of a semiconductor chip having an electrode pad to be wire-bonded to a header, securing of a fixing region is difficult since the spread of an Ag paste cannot be controlled, therefore, there has existed a problem such that stable manufacturing could not be carried out. Also, there existed a problem such that realization of stable manufacturing resulted in an excessively large external package form. A projection part is provided in a header, and a fixing region of a bonding wire is secured by arranging a chip at a position shifted in a direction to become distant from the projection part. An electrode pad to be connected to the header is arranged closer to the chip center than the other electrode pads of the identical chip side, and a wire is extended therefrom to the projection part or in the vicinity thereof so as to cross the chip and is fixed. Thereby, downsizing of the package and stable manufacturing are realized.
    Type: Application
    Filed: February 6, 2003
    Publication date: September 4, 2003
    Inventors: Koichi Hirata, Osamu Isaki, Tsutomu Aono, Toshikazu Hirai, Tetsuro Asano
  • Publication number: 20030129788
    Abstract: In a method of manufacturing a compound semiconductor device, individual chip patterns are projected onto a (100) surface of a GaAs wafer so that the columns and rows of the chip patterns are aligned in a direction slanting by 45 degrees with respect to a [O11] direction of the GaAs wafer. The wafer is diced along this slanting direction and chipping along the edges of the individual separated chips is greatly reduced.
    Type: Application
    Filed: December 26, 2002
    Publication date: July 10, 2003
    Applicant: SANYO ELECTRIC CO., LTD.
    Inventors: Tetsuro Asano, Masahiro Uekawa, Koichi Hirata, Mikito Sakakibara
  • Patent number: 6580107
    Abstract: The conventional compound semiconductor switching device is prone to have a large chip size as the gate width needs to be large for achieving a low insertion loss and the separation between the connecting pad and the circuit wiring needs to be larger than 20 &mgr;m for obtaining a proper isolation between them. The overall chip size is reduced, first, by reducing the gate width of the switching FET operating at frequencies above 2.4 GHz to 700 &mgr;m or smaller together with the omission of the shunt FET, and, then, by reducing the separation between the connecting pad and the circuit wiring to 20 &mgr;m or smaller. This reduction of the separation is made possible by the introduction of an insulating film and a impurity region between the outermost portion of the connecting pad and the substrate for preventing the extension of the depletion layer.
    Type: Grant
    Filed: October 10, 2001
    Date of Patent: June 17, 2003
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tetsuro Asano, Toshikazu Hirai, Takayoshi Higashino, Koichi Hirata, Mikito Sakakibara