Patents by Inventor Kiyokazu Ishige

Kiyokazu Ishige 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: 8675385
    Abstract: A first semiconductor device is formed over a substrate and includes a first insulation film, a first electrode, and a first diffusion layer. A second semiconductor device is formed over a substrate and includes a second insulation film, a second electrode, and a second diffusion layer. The second electrode is coupled to the first electrode. A control transistor allows one of a source and a drain to be coupled to the first electrode and the second electrode, allows the other one of the source and the drain to be coupled to a bit line, and allows a gate electrode to be coupled to a word line. A first potential control line is coupled to the first diffusion layer and controls a potential of the first diffusion layer. A second potential control line is coupled to the second diffusion layer and controls a potential of the second diffusion layer.
    Type: Grant
    Filed: June 24, 2011
    Date of Patent: March 18, 2014
    Assignee: Renesas Electronics Corporation
    Inventors: Hiromichi Takaoka, Kenichi Hidaka, Hiroshi Tsuda, Kiyokazu Ishige, Yoshitaka Kubota, Takuji Onuma
  • Patent number: 8530949
    Abstract: An antifuse whose internal written information cannot be analyzed even by utilizing methods to determine whether there is a charge-up in the electrodes. The antifuse includes a gate insulation film, a gate electrode, and a first diffusion layer. A second diffusion layer is isolated from the first diffusion layer by way of a device isolator film, and is the same conduction type as the first diffusion layer. The gate wiring is formed as one integrated piece with the gate electrode, and extends over the device isolator film. A common contact couples the gate wiring to the second diffusion layer. The gate electrode is comprised of semiconductor material such as polysilicon that is doped with impurities of the same conduction type as the first diffusion layer. The second diffusion layer is coupled only to the common contact.
    Type: Grant
    Filed: September 30, 2011
    Date of Patent: September 10, 2013
    Assignee: Renesas Electronics Corporation
    Inventors: Takuji Onuma, Kenichi Hidaka, Hiromichi Takaoka, Yoshitaka Kubota, Hiroshi Tsuda, Kiyokazu Ishige
  • Publication number: 20120080736
    Abstract: An antifuse whose internal written information cannot be analyzed even by utilizing methods to determine whether there is a charge-up in the electrodes. The antifuse includes a gate insulation film, a gate electrode, and a first diffusion layer. A second diffusion layer is isolated from the first diffusion layer by way of a device isolator film, and is the same conduction type as the first diffusion layer. The gate wiring is formed as one integrated piece with the gate electrode, and extends over the device isolator film. A common contact couples the gate wiring to the second diffusion layer. The gate electrode is comprised of semiconductor material such as polysilicon that is doped with impurities of the same conduction type as the first diffusion layer. The second diffusion layer is coupled only to the common contact.
    Type: Application
    Filed: September 30, 2011
    Publication date: April 5, 2012
    Applicant: RENESAS ELECTRONICS CORPORATION
    Inventors: Takuji ONUMA, Kenichi HIDAKA, Hiromichi TAKAOKA, Yoshitaka KUBOTA, Hiroshi TSUDA, Kiyokazu ISHIGE
  • Publication number: 20120044741
    Abstract: A first semiconductor device is formed over a substrate and includes a first insulation film, a first electrode, and a first diffusion layer. A second semiconductor device is formed over a substrate and includes a second insulation film, a second electrode, and a second diffusion layer. The second electrode is coupled to the first electrode. A control transistor allows one of a source and a drain to be coupled to the first electrode and the second electrode, allows the other one of the source and the drain to be coupled to a bit line, and allows a gate electrode to be coupled to a word line. A first potential control line is coupled to the first diffusion layer and controls a potential of the first diffusion layer. A second potential control line is coupled to the second diffusion layer and controls a potential of the second diffusion layer.
    Type: Application
    Filed: June 24, 2011
    Publication date: February 23, 2012
    Applicant: Renesas Electronics Corporation
    Inventors: Hiromichi Takaoka, Kenichi Hidaka, Hiroshi Tsuda, Kiyokazu Ishige, Yoshitaka Kubota, Takuji Onuma
  • Patent number: 6979856
    Abstract: A semiconductor memory device includes a first insulating film provided on a semiconductor substrate between first and second diffusion regions, a first gate electrode provided on the first insulating film, a second insulating film provided on the semiconductor substrate between the second diffusion region and a third diffusion region, and a second gate electrode provided on the second insulating film. The first and second diffusion regions, first insulating film, and first gate electrode constitute a first memory cell, while the second and third diffusion regions, second insulating film, and second gate electrode constitute a second memory cell. The first and second gate electrodes are connected in common to form a word line electrode. The first and third diffusion regions are connected to first and second read bit lines. The second diffusion region is connected to a program and erase bit line.
    Type: Grant
    Filed: August 27, 2003
    Date of Patent: December 27, 2005
    Assignee: NEC Electronics Corporation
    Inventors: Teiichiro Nishizaka, Isami Sakai, Akira Yoshino, Shinichi Kawai, Kiyokazu Ishige, Tomohiro Hamajima, Motoko Tanaka
  • Publication number: 20040071011
    Abstract: A semiconductor memory device includes a first insulating film provided on a semiconductor substrate between first and second diffusion regions, a first gate electrode provided on the first insulating film, a second insulating film provided on the semiconductor substrate between the second diffusion region and a third diffusion region, and a second gate electrode provided on the second insulating film are included, wherein the first and second diffusion regions, first insulating film, and first gate electrode constitute a first memory cell, while the second and third diffusion regions, second insulating film, and second gate electrode constitute a second memory cell. The first and second gate electrodes are connected in common to form a word line electrode. The first and third diffusion regions are connected to first and second read bit lines disposed on a layer overlying the semiconductor substrate.
    Type: Application
    Filed: August 27, 2003
    Publication date: April 15, 2004
    Applicant: NEC Electronics Corporation
    Inventors: Teiichiro Nishizaka, Isami Sakai, Akira Yoshino, Shinichi Kawai, Kiyokazu Ishige, Tomohiro Hamajima, Motoko Tanaka
  • Patent number: 6677196
    Abstract: A semiconductor memory device is provided, which makes it possible to increase the capacitance of capacitors in the capacitor section without degrading the withstand voltage of the capacitor dielectric. This device comprises a memory cell section including floating-gate type transistors and a capacitor section including capacitors. The memory cell section and the capacitor section are formed on a semiconductor substrate. Each of the transistors has a first gate dielectric, a floating gate, a second gate dielectric, and a control gate. Each of the capacitors has a lower electrode, a capacitor dielectric, and an upper electrode. A first part of the capacitors is/are designed to be applied with a first voltage and a second part thereof is/are applied with a second voltage on operation, where the first voltage is lower than the second voltage. Each of the first part of the capacitors has a recess formed on the lower electrode, thereby increasing its capacitance.
    Type: Grant
    Filed: November 26, 2002
    Date of Patent: January 13, 2004
    Assignee: NEC Electronics Corporation
    Inventor: Kiyokazu Ishige
  • Publication number: 20030075750
    Abstract: A semiconductor memory device is provided, which makes it possible to increase the capacitance of capacitors in the capacitor section without degrading the withstand voltage of the capacitor dielectric. This device comprises a memory cell section including floating-gate type transistors and a capacitor section including capacitors. The memory cell section and the capacitor section are formed on a semiconductor substrate. Each of the transistors has a first gate dielectric, a floating gate, a second gate dielectric, and a control gate. Each of the capacitors has a lower electrode, a capacitor dielectric, and an upper electrode. A first part of the capacitors is/are designed to be applied with a first voltage and a second part thereof is/are applied with a second voltage on operation, where the first voltage is lower than the second voltage. Each of the first part of the capacitors has a recess formed on the lower electrode, thereby increasing its capacitance.
    Type: Application
    Filed: November 26, 2002
    Publication date: April 24, 2003
    Applicant: NEC Corporation
    Inventor: Kiyokazu Ishige
  • Patent number: 6538927
    Abstract: The present invention enables to complete a data erase of memory cells of a group in a semiconductor storage device where a data erase is uniformly performed to memory cells of a group until all the cell threshold values become below a reference and memory cells having a cell threshold value below a lower limit are supplied with an electric charge. When a production error occurs in such a way that some memory cells in a predetermined position of a group have a lover erase speed, the semiconductor device is formed in such a way that these memory cells have an erase speed higher than an ideal value. When some memory cells of a group have a lower erase speed, an excessive erase is performed in most memory cells of the group requiring electric charge supply, which increase the erase time as a whole. However, when only some memory cells of a group have a higher erase speed, an excessive erase requiring electric charge supply occurs only in some memories and accordingly, it is possible to rapidly complete the data.
    Type: Grant
    Filed: June 26, 2002
    Date of Patent: March 25, 2003
    Assignee: NEC Corporation
    Inventors: Kazuhiko Sanada, Kenji Saitou, Kiyokazu Ishige, Hitoshi Nakamura
  • Patent number: 6515326
    Abstract: A semiconductor memory device is provided, which makes it possible to increase the capacitance of capacitors in the capacitor section without degrading the withstand voltage of the capacitor dielectric. This device comprises a memory cell section including floating-gate type transistors and a capacitor section including capacitors. The memory cell section and the capacitor section are formed on a semiconductor substrate. Each of the transistors has a first gate dielectric, a floating gate, a second gage dielectric, and a control gate. Each of the capacitors has a lower electrode, a capacitor dielectric, and an upper electrode. A first part of the capacitors is/are designed to be applied with a first voltage and a second part thereof is/are applied with a second voltage on operation, where the first voltage is lower than the second voltage. Each of the first part of the capacitors has a recess formed on the lower electrode, thereby increasing its capacitance.
    Type: Grant
    Filed: June 25, 2001
    Date of Patent: February 4, 2003
    Assignee: NEC Corporation
    Inventor: Kiyokazu Ishige
  • Patent number: 6503797
    Abstract: The present invention prevents a charge-up during a wiring layer etching in a nonvolatile semiconductor storage apparatus, having a floating gate and a control gate to which both of positive and negative voltages are applied during a memory cell operation, by providing a current path from the control gate to a substrate via a charge-up preventing element. A first well is formed in the substrate. A second well is formed in the first well. The charge-up preventing element is formed in the second well. The substrate and second well are of one conductive type (p or n) and the first well and charge-up preventing element are of the other conductive type. Before memory cell operation, the control gate is disconnected from the charge-up preventing element.
    Type: Grant
    Filed: August 17, 2001
    Date of Patent: January 7, 2003
    Assignee: NEC Corporation
    Inventor: Kiyokazu Ishige
  • Patent number: 6498753
    Abstract: The present invention enables to complete a data erase of memory cells of a group in a semiconductor storage device where a data erase is uniformly performed to memory cells of a group until all the cell threshold values become below a reference and memory cells having a cell threshold value below a lower limit are supplied with an electric charge. When a production error occurs in such a way that some memory cells in a predetermined position of a group have a lower erase speed, the semiconductor device is formed in such a way that these memory cells have an erase speed higher than an ideal value. When some memory cells of a group have a lower erase speed, an excessive erase is performed in most memory cells of the group requiring electric charge supply, which increase the erase time as a whole.
    Type: Grant
    Filed: August 31, 2001
    Date of Patent: December 24, 2002
    Assignee: NEC Corporation
    Inventors: Kazuhiko Sanada, Kenji Saitou, Kiyokazu Ishige, Hitoshi Nakamura
  • Patent number: 6396098
    Abstract: There is provided a semiconductor memory device including a semiconductor substrate, a floating gate type transistor formed on the semiconductor substrate, acting as a memory cell of the semiconductor memory device, and a charge pump circuit formed on the semiconductor substrate. The transistor includes (a) a first gate insulating film formed on the semiconductor substrate, (b) a floating gate electrode formed on the first gate insulating film, (c) a second gate insulating film formed on the floating gate electrode, and (d) a control gate electrode formed on the second gate insulating film. The charge pump circuit includes (a) a plurality of diode devices formed on a third insulating layer formed on the semiconductor substrate, and electrically connected with each other in series, and (b) a plurality of capacitors each of which is electrically connected to a terminal of each of the diode devices.
    Type: Grant
    Filed: May 30, 1997
    Date of Patent: May 28, 2002
    Assignee: NEC Corporation
    Inventor: Kiyokazu Ishige
  • Patent number: 6392268
    Abstract: The present invention prevents a charge-up during a wiring layer etching in a nonvolatile semiconductor storage apparatus having a floating gate and a control gate to which both of positive and negative voltages are applied during a memory cell operation. On a semiconductor substrate 51 of a first conductive type, a first well 52 of a second conductive type is formed to oppose to the first conductive type. In the first well 52, a second well 53 of the first conductive type is formed. On a main surface of the second well 53 is formed a composite gate 8 consisting of a first gate insulation film 4, a floating gate 5, a second gate insulation film 6, and a control gate 7 which are successively layered. On a surface of the second well 53 are formed by way of ion implantation, a source, a drain, and a charge-up preventing element diffusion layer 18 of the second conductive type.
    Type: Grant
    Filed: September 17, 1998
    Date of Patent: May 21, 2002
    Assignee: NEC Corporation
    Inventor: Kiyokazu Ishige
  • Publication number: 20020011624
    Abstract: A nonvolatile semiconductor memory device and a method of fabricating the device are provided that allow the use of dry etching when removing the ONO film and that eliminate the danger of etching the silicon substrate in the gate oxide film formation areas even in the event of over-etching.
    Type: Application
    Filed: September 18, 2001
    Publication date: January 31, 2002
    Applicant: NEC Corporation
    Inventor: Kiyokazu Ishige
  • Publication number: 20020008995
    Abstract: The present invention enables to complete a data erase of memory cells of a group in a semiconductor storage device where a data erase is uniformly performed to memory cells of a group until all the cell threshold values become below a reference and memory cells having a cell threshold value below a lower limit are supplied with an electric charge. When a production error occurs in such a way that some memory cells in a predetermined position of a group have a lower erase speed, the semiconductor device is formed in such a way that these memory cells have an erase speed higher than an ideal value. When some memory cells of a group have a lower erase speed, an excessive erase is performed in most memory cells of the group requiring electric charge supply, which increase the erase time as a whole.
    Type: Application
    Filed: August 31, 2001
    Publication date: January 24, 2002
    Inventors: Kazuhiko Sanada, Kenji Saitou, Kiyokazu Ishige, Hitoshi Nakamura
  • Publication number: 20010054736
    Abstract: A semiconductor memory device is provided, which makes it possible to increase the capacitance of capacitors in the capacitor section without degrading the withstand voltage of the capacitor dielectric. This device comprises a memory cell section including floating-gate type transistors and a capacitor section including capacitors. The memory cell section and the capacitor section are formed on a semiconductor substrate. Each of the transistors has a first gate dielectric, a floating gate, a second gate dielectric, and a control gate. Each of the capacitors has a lower electrode, a capacitor dielectric, and an upper electrode. A first part of the capacitors is/are designed to be applied with a first voltage and a second part thereof is/are applied with a second voltage on operation, where the first voltage is lower than the second voltage. Each of the first part of the capacitors has a recess formed on the lower electrode, thereby increasing its capacitance.
    Type: Application
    Filed: June 25, 2001
    Publication date: December 27, 2001
    Inventor: Kiyokazu Ishige
  • Publication number: 20010055847
    Abstract: The present invention prevents a charge-up during a wiring layer etching in a nonvolatile semiconductor storage apparatus having a floating gate and a control gate to which both of positive and negative voltages are applied during a memory cell operation.
    Type: Application
    Filed: August 17, 2001
    Publication date: December 27, 2001
    Applicant: NEC CORPORATION
    Inventor: Kiyokazu Ishige
  • Publication number: 20010052616
    Abstract: The present invention prevents a charge-up during a wiring layer etching in a nonvolatile semiconductor storage apparatus having a floating gate and a control gate to which both of positive and negative voltages are applied during a memory cell operation.
    Type: Application
    Filed: September 17, 1998
    Publication date: December 20, 2001
    Inventor: KIYOKAZU ISHIGE
  • Patent number: 6330191
    Abstract: The present invention enables to complete a data erase of memory cells of a group in a semiconductor storage device where a data erase is uniformly performed to memory cells of a group until all the cell threshold values become below a reference and memory cells having a cell threshold value below a lower limit are supplied with an electric charge. When a production error occurs in such a way that some memory cells in a predetermined position of a group have a lower erase speed, the semiconductor device is formed in such a way that these memory cells have an erase speed higher than an ideal value. When some memory cells of a group have a lower erase speed, an excessive erase is performed in most memory cells of the group requiring electric charge supply, which increase the erase time as a whole.
    Type: Grant
    Filed: November 29, 2000
    Date of Patent: December 11, 2001
    Assignee: NEC Corporation
    Inventors: Kazuhiko Sanada, Kenji Saitou, Kiyokazu Ishige, Hitoshi Nakamura