Patents by Inventor Tadashi Iguchi

Tadashi Iguchi 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).

  • Publication number: 20100117135
    Abstract: A semiconductor device is formed on a SOI substrate having a semiconductor substrate, a buried oxide film formed on the semiconductor substrate, and a semiconductor layer formed on the buried oxide film, the semiconductor substrate having a first conductive type, the semiconductor layer having a second conductive type, wherein the buried oxide film has a first opening opened therethrough for communicating the semiconductor substrate with the semiconductor layer, the semiconductor layer is arranged to have a first buried portion buried in the first opening in contact with the semiconductor substrate and a semiconductor layer main portion positioned on the first buried portion and on the buried oxide film, the semiconductor substrate has a connection layer buried in a surface of the semiconductor substrate and electrically connected to the first buried portion in the first opening, the connection layer having the second conductive type, and the semiconductor device includes a contact electrode buried in a secon
    Type: Application
    Filed: September 22, 2009
    Publication date: May 13, 2010
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Makoto MIZUKAMI, Kiyohito Nishihara, Masaki Kondo, Takashi Izumida, Hirokazu Ishida, Atsushi Fukumoto, Fumiki Aiso, Daigo Ichinose, Tadashi Iguchi
  • Publication number: 20090286401
    Abstract: A method of fabricating a semiconductor device according to one embodiment includes: forming a core material on a workpiece; forming a coating film comprising an amorphous material so as to cover an upper surface and side faces of the core material; crystallizing the coating film by applying heat treatment; forming a sidewall mask by removing the crystallized coating film while leaving a portion thereof located on the side faces of the core material; removing the core material after forming the sidewall mask; and etching the workpiece using the sidewall mask as a mask after removing the core material.
    Type: Application
    Filed: March 26, 2009
    Publication date: November 19, 2009
    Inventors: Daigo Ichinose, Tadashi Iguchi
  • Publication number: 20090267138
    Abstract: A charge trap type non-volatile memory device has memory cells formed on a silicon substrate at a predetermined interval via an element isolation trench along a first direction in which word lines extend. Each of the memory cells has a tunnel insulating film formed on the silicon substrate, a charge film formed on the tunnel insulating film, and a common block film formed on the charge film. The common block film is formed in common with the memory cells along first direction. An element isolation insulating film buried in the element isolation trench has an upper portion of a side wall of the element isolation insulating film which contacts with a side wall of the charge film in each of the memory cells and a top portion of the element isolation insulating film which contacts with the common block film. A control electrode film is formed on the common block film.
    Type: Application
    Filed: April 8, 2009
    Publication date: October 29, 2009
    Inventor: Tadashi IGUCHI
  • Patent number: 7586786
    Abstract: A method of reading out data from nonvolatile semiconductor memory including the steps of applying a first voltage to a bit line contact; applying a second voltage to a source line contact, wherein the second voltage is substantially smaller than the first voltage; applying a third voltage gates of third and fourth select gate transistors, the third voltage configured to bring the third and fourth select gate transistors into conduction; applying a fourth voltage to gates of the plurality of memory cell transistors of a second memory cell unit, the fourth voltage configured to bring the plurality of memory cell transistors of the second memory cell unit into conduction or not, depending on the data that is stored in the memory cell unit; and applying a fifth voltage to gates of the plurality of memory cell transistors of a first memory cell unit, the fifth voltage configured to bring the plurality of memory cell transistors of the first memory cell unit into conduction; wherein the fifth voltage is bigger tha
    Type: Grant
    Filed: April 21, 2008
    Date of Patent: September 8, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yasuhiko Matsunaga, Fumitaka Arai, Makoto Sakuma, Tadashi Iguchi, Hisashi Watanobe, Hiroaki Tsunoda
  • Patent number: 7582928
    Abstract: A non-volatile semiconductor memory device, which is intended to prevent data destruction by movements of electric charges between floating gates and thereby improve the reliability, includes element isolation/insulation films buried into a silicon substrate to isolate stripe-shaped element-forming regions. Formed on the substrate area floating gate via a first gate insulating film and further a control gate via a second gate insulating film. Source and drain diffusion layers are formed in self-alignment with control gates. The second gate insulating film on the floating gate is divided and separated together with the floating gate by slits above the element isolation/insulation films into discrete portions of individual memory cells.
    Type: Grant
    Filed: August 3, 2007
    Date of Patent: September 1, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tadashi Iguchi, Yoshiaki Himeno, Hiroaki Tsunoda
  • Publication number: 20090212352
    Abstract: A semiconductor memory device has a semiconductor substrate, a plurality of word lines formed at predetermined intervals on the semiconductor substrate, each word line having a gate insulating film, a charge storage layer, a first insulating film, and a controlling gate electrode which are stacked in order, and including a metal oxide layer above the level of the gate insulating film, a second insulating film covering a side of the word line and a surface of the semiconductor substrate between the word lines, and having a film thickness of 15 nm or less, and a third insulating film formed between the word lines adjacent to each other such that a region below the level of the metal oxide layer has a cavity.
    Type: Application
    Filed: February 24, 2009
    Publication date: August 27, 2009
    Inventors: Kenji AOYAMA, Eiji Ito, Masahiro Kiyotoshi, Tadashi Iguchi, Moto Yabuki
  • Patent number: 7550342
    Abstract: A nonvolatile semiconductor memory device whose gate structure of a transistor other than a memory cell transistor has a same stacked gate structure as the memory cell transistor, the gate structure comprising a semiconductor substrate, a first insulation film provided on the semiconductor substrate, a first conductive film provided on the first insulation film, a second insulation film, provided on the first conductive film, having an opening, a spacer provided on the second insulation film to define the opening, and a second conductive film provided on the spacer and electrically connected to the first conductive film via the opening.
    Type: Grant
    Filed: March 6, 2007
    Date of Patent: June 23, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koichi Matsuno, Tadashi Iguchi
  • Publication number: 20090057749
    Abstract: A memory cell includes a floating gate electrode, a first inter-electrode insulating film and a control gate electrode. A peripheral transistor includes a lower electrode, a second inter-electrode insulating film and an upper electrode. The lower electrode and the upper electrode are electrically connected via an opening provided on the second inter-electrode insulating film. The first and second inter-electrode insulating films include a high-permittivity material, the first inter-electrode insulating film has a first structure, and the second inter-electrode insulating film has a second structure different from the first structure.
    Type: Application
    Filed: August 8, 2008
    Publication date: March 5, 2009
    Inventors: Kenji GOMIKAWA, Tadashi Iguchi, Mitsuhiro Noguchi, Shoichi Watanabe
  • Patent number: 7488646
    Abstract: A non-volatile semiconductor memory device, which is intended to prevent data destruction by movements of electric charges between floating gates and thereby improve the reliability, includes element isolation/insulation films buried into a silicon substrate to isolate stripe-shaped element-forming regions. Formed on the substrate are a floating gate via a first gate insulating film and further a control gate via a second gate insulating film. Source and drain diffusion layers are formed in self-alignment with control gates. The second gate insulating film on the floating gate is divided and separated together with the floating gate by slits above the element isolation/insulation films into discrete portions of individual memory cells.
    Type: Grant
    Filed: March 13, 2007
    Date of Patent: February 10, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tadashi Iguchi, Yoshiaki Himeno, Hiroaki Tsunoda
  • Publication number: 20090016108
    Abstract: A method of reading out data from nonvolatile semiconductor memory including the steps of applying a first voltage to a bit line contact; applying a second voltage to a source line contact, wherein the second voltage is substantially smaller than the first voltage; applying a third voltage gates of third and fourth select gate transistors, the third voltage configured to bring the third and fourth select gate transistors into conduction; applying a fourth voltage to gates of the plurality of memory cell transistors of a second memory cell unit, the fourth voltage configured to bring the plurality of memory cell transistors of the second memory cell unit into conduction or not, depending on the data that is stored in the memory cell unit; and applying a fifth voltage to gates of the plurality of memory cell transistors of a first memory cell unit, the fifth voltage configured to bring the plurality of memory cell transistors of the first memory cell unit into conduction; wherein the fifth voltage is bigger tha
    Type: Application
    Filed: April 21, 2008
    Publication date: January 15, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yasuhiko Matsunaga, Fumitaka Arai, Makoto Sakuma, Tadashi Iguchi, Hisashi Watanobe, Hiroaki Tsunoda
  • Publication number: 20080308859
    Abstract: A semiconductor device including a semiconductor substrate, and a memory cell and a peripheral circuit provided on the semiconductor substrate, the memory cell having a first insulating film, a first electrode layer, a second insulating film, and a second electrode layer provided on the semiconductor substrate in order, and the peripheral circuit having the first insulating film, the first electrode layer, the second insulating film having an opening for the peripheral circuit, and the second electrode layer electrically connected to the first electrode layer through the opening for the peripheral circuit, wherein a thickness of the first electrode layer under the second insulating film of the peripheral circuit is thicker than a thickness of the first electrode layer of the memory cell.
    Type: Application
    Filed: June 9, 2008
    Publication date: December 18, 2008
    Inventors: Masao Iwase, Tadashi Iguchi
  • Patent number: 7382015
    Abstract: A non-volatile semiconductor memory device, which is intended to prevent data destruction by movements of electric charges between floating gates and thereby improve the reliability, includes element isolation/insulation films buried into a silicon substrate to isolate stripe-shaped element-forming regions. Formed on the substrate are a floating gate via a first gate insulating film and further a control gate via a second gate insulating film. Source and drain diffusion layers are formed in self-alignment with control gates. The second gate insulating film on the floating gate is divided and separated together with the floating gate by slits above the element isolation/insulation films into discrete portions of individual memory cells.
    Type: Grant
    Filed: March 31, 2005
    Date of Patent: June 3, 2008
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tadashi Iguchi, Yoshiaki Himeno, Hiroaki Tsunoda
  • Patent number: 7382649
    Abstract: A nonvolatile semiconductor memory includes memory cell units, each having memory cell transistors aligned in a column direction and capable of writing and erasing electronic data; and contacts on active areas, arranged on both sides of memory cell unit arrays in which the memory cell units are serially connected in the column direction, and the contacts on active areas are shared by the memory cell unit arrays; wherein, the respective memory cell unit arrays are located having a periodical shift length equal to and or more than the integral multiple length of the periodical length of the memory cell units aligned in the column direction so as to be staggered from each other as compared with neighboring memory cell unit arrays aligned in the row direction.
    Type: Grant
    Filed: June 9, 2005
    Date of Patent: June 3, 2008
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yasuhiko Matsunaga, Fumitaka Arai, Makoto Sakuma, Tadashi Iguchi, Hisashi Watanobe, Hiroaki Tsunoda
  • Publication number: 20070293018
    Abstract: In fabrication of a semiconductor device, a first insulating film, electrode film and silicon nitride film sequentially stacked on a semiconductor substrate are etched with the substrate so that a trench is formed. The electrode film is then exposed. A second insulating film buried in the trench is isotropically etched so that an upper side wall of the electrode film is exposed, so that a side end of an upper surface of the insulating film is located between the upper surfaces of the substrate and electrode film and so that a middle upper portion of an upper surface of the second insulating film is higher than the side end and lower than the upper surface of the first electrode film, A third insulating film is formed on the upper surface of the first electrode film so as to entirely cover the upper surface of the second insulating film.
    Type: Application
    Filed: August 13, 2007
    Publication date: December 20, 2007
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Ryuichi KAMO, Hisashi Watanobe, Tadashi Iguchi
  • Publication number: 20070278562
    Abstract: A non-volatile semiconductor memory device, which is intended to prevent data destruction by movements of electric charges between floating gates and thereby improve the reliability, includes element isolation/insulation films buried into a silicon substrate to isolate stripe-shaped element-forming regions. Formed on the substrate area floating gate via a first gate insulating film and further a control gate via a second gate insulating film. Source and drain diffusion layers are formed in self-alignment with control gates. The second gate insulating film on the floating gate is divided and separated together with the floating gate by slits above the element isolation/insulation films into discrete portions of individual memory cells.
    Type: Application
    Filed: August 3, 2007
    Publication date: December 6, 2007
    Applicant: KABUSHI KAISHA TOSHIBA
    Inventors: Tadashi Iguchi, Yoshiaki Himeno, Hiroaki Tsunoda
  • Patent number: 7276757
    Abstract: A semiconductor device includes a semiconductor substrate including a first upper surface, a first insulating film including an upper portion including a first side wall having a first upper end and a second upper surface having a second upper end, a second insulating film formed on the first upper surface of the substrate, a floating gate electrode including a third upper surface, a second side wall and a lower surface, a third insulating film, and a control gate electrode. A height of the second upper end is lower than a height of the third upper surface and higher than a height of the first upper end relative to the first upper surface. The first upper end is located at a position higher than the lower surface of the floating gate electrode. The entire second side wall is aligned with the first side wall of the first insulating film.
    Type: Grant
    Filed: February 18, 2005
    Date of Patent: October 2, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Ryuichi Kamo, Hisashi Watanobe, Tadashi Iguchi
  • Publication number: 20070166919
    Abstract: A non-volatile semiconductor memory device, which is intended to prevent data destruction by movements of electric charges between floating gates and thereby improve the reliability, includes element isolation/insulation films buried into a silicon substrate to isolate stripe-shaped element-forming regions. Formed on the substrate are a floating gate via a first gate insulating film and further a control gate via a second gate insulating film. Source and drain diffusion layers are formed in self-alignment with control gates. The second gate insulating film on the floating gate is divided and separated together with the floating gate by slits above the element isolation/insulation films into discrete portions of individual memory cells.
    Type: Application
    Filed: March 13, 2007
    Publication date: July 19, 2007
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tadashi Iguchi, Yoshiaki Himeno, Hiroaki Tsunoda
  • Publication number: 20070148854
    Abstract: A nonvolatile semiconductor memory device whose gate structure of a transistor other than a memory cell transistor has a same stacked gate structure as the memory cell transistor, the gate structure comprising a semiconductor substrate, a first insulation film provided on the semiconductor substrate, a first conductive film provided on the first insulation film, a second insulation film, provided on the first conductive film, having an opening, a spacer provided on the second insulation film to define the opening, and a second conductive film provided on the spacer and electrically connected to the first conductive film via the opening.
    Type: Application
    Filed: March 6, 2007
    Publication date: June 28, 2007
    Inventors: Koichi Matsuno, Tadashi Iguchi
  • Patent number: 7208801
    Abstract: A nonvolatile semiconductor memory device whose gate structure of a transistor other than a memory cell transistor has a same stacked gate structure as the memory cell transistor, the gate structure comprising a semiconductor substrate, a first insulation film provided on the semiconductor substrate, a first conductive film provided on the first insulation film, a second insulation film, provided on the first conductive film, having an opening, a spacer provided on the second insulation film to define the opening, and a second conductive film provided on the spacer and electrically connected to the first conductive film via the opening.
    Type: Grant
    Filed: May 26, 2005
    Date of Patent: April 24, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koichi Matsuno, Tadashi Iguchi
  • Publication number: 20060244098
    Abstract: A semiconductor device comprises a semiconductor substrate having a substrate top surface on which a device should be formed; a gate electrode having an opposed surface opposed to said substrate top surface, and electrically insulated from said semiconductor substrate by a gate insulating film, a trench formed through said gate electrode into said semiconductor substrate to electrically isolate a device region for forming a device from the remainder region of said substrate top surface, a first boundary end portion, which is defined between a substrate side surface of said semiconductor substrate forming a part of the side surface of said trench and said substrate top surface, and a second boundary end portion, which is defined between a gate side surface of said gate electrode forming another part of the side surface of said trench and said opposed surface, wherein said first boundary end portion and said second boundary end portion have spherical shapes having a curvature radius not smaller than 30 angstrom
    Type: Application
    Filed: June 30, 2006
    Publication date: November 2, 2006
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Tadashi Iguchi, Hiroaki Tsunoda, Koichi Matsuno