Patents by Inventor Hiroyoshi Tanimoto

Hiroyoshi Tanimoto 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: 7393748
    Abstract: A NAND cell unit is formed with an advanced gate forming process on a semiconductor layer of a first conductivity type, which is formed on a semiconductor substrate of the first conductivity type with an insulating film interposed therebetween. First impurity-doped layers of a second conductivity type are formed on the semiconductor layer, which serve as channel regions of the select gate transistors Bit line contact- and source line contact-use second impurity-doped layers of the first conductivity type are formed at bit line and source line contact portions, sidewalls of which are covered with an insulating film.
    Type: Grant
    Filed: December 12, 2006
    Date of Patent: July 1, 2008
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Fumitaka Arai, Toshiyuki Enda, Hiroyoshi Tanimoto, Naoki Kusunoki, Nobutoshi Aoki, Riichiro Shirota, Hiroshi Watanabe, Takamitsu Ishihara
  • Publication number: 20070290253
    Abstract: A nonvolatile semiconductor memory device includes: a semiconductor region; device isolation regions placed in the semiconductor region and extending in a column direction; a semiconductor layer placed on the semiconductor region and between the device isolation regions, and having a convex shape in cross section along a row direction; source/drain regions placed in the semiconductor layer and spaced from each other; a gate insulating film placed on the semiconductor layer between the source/drain regions; a floating gate electrode layer placed on the gate insulating film; an intergate insulating film placed on the floating gate electrode layer and upper surfaces of the device isolation regions; and a control gate electrode layer placed on the intergate insulating film and extending in the row direction.
    Type: Application
    Filed: June 20, 2007
    Publication date: December 20, 2007
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Masaru KITO, Nobutoshi Aoki, Masaru Kidoh, Ryota Katsumata, Masaki Kondo, Naoki Kusunoki, Toshiyuki Enda, Sanae Ito, Hiroyoshi Tanimoto, Hideaki Aochi, Akihiro Nitayama, Riichiro Shirota
  • Publication number: 20070237002
    Abstract: A non-volatile semiconductor memory includes a plurality of memory cell transistors, each of the plurality of memory cell transistors includes: a source region having a first conductivity type and in contact with a buried insulating layer on a supporting substrate; a drain region having the first conductivity type and in contact with the buried insulating layer; and a channel region having the first conductivity type and provided between the source region and the drain region so as to contact the buried insulating layer, wherein a thickness of the channel region is more than one nm and not more than a value obtained by adding seven nm to a half value of a gate length of the memory cell transistor.
    Type: Application
    Filed: June 14, 2007
    Publication date: October 11, 2007
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Toshiyuki Enda, Hiroyoshi Tanimoto, Naoki Kusunoki, Nobutoshi Aoki, Fumitaka Arai, Riichiro Shirota
  • Publication number: 20070170483
    Abstract: A transistor formed on a semiconductor substrate has a gate electrode formed via a gate insulating film and first and second diffusion layers formed in the semiconductor substrate, the first and second diffusion layers being positioned at both sides of the gate electrode. A first electrode is connected to the first diffusion layer of the transistor. A capacitor insulating film formed on the first electrode is formed of a silicon oxide film containing a substrate which is faster than Cu in diffusion velocity and which more readily reacts with oxygen than Cu does. A second electrode formed on the capacitor insulating film is formed of one of a Cu layer and another Cu layer containing the substance.
    Type: Application
    Filed: May 12, 2006
    Publication date: July 26, 2007
    Inventors: Yumi Hayashi, Hayato Nasu, Kazumichi Tsumura, Takamasa Usui, Hiroyoshi Tanimoto
  • Publication number: 20070138536
    Abstract: A NAND cell unit is formed with an advanced gate forming process on a semiconductor layer of a first conductivity type, which is formed on a semiconductor substrate of the first conductivity type with an insulating film interposed therebetween. First impurity-doped layers of a second conductivity type are formed on the semiconductor layer, which serve as channel regions of the select gate transistors Bit line contact- and source line contact-use second impurity-doped layers of the first conductivity type are formed at bit line and source line contact portions, sidewalls of which are covered with an insulating film.
    Type: Application
    Filed: December 12, 2006
    Publication date: June 21, 2007
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Fumitaka ARAI, Toshiyuki Enda, Hiroyoshi Tanimoto, Naoki Kusunoki, Nobutoshi Aoki, Riichiro Shirota, Hiroshi Watanabe, Takamitsu Ishihara
  • Publication number: 20070102749
    Abstract: A semiconductor memory device includes: a semiconductor substrate; a semiconductor layer formed on the semiconductor substrate with an insulating film interposed therebetween, the semiconductor layer being in contact with the semiconductor substrate via an opening formed in the insulating film; and a NAND cell unit formed on the semiconductor layer with a plurality of electrically rewritable and non-volatile memory cells connected in series and first and second select gate transistors disposed at both ends thereof.
    Type: Application
    Filed: October 16, 2006
    Publication date: May 10, 2007
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Riichiro Shirota, Fumitaka Arai, Toshiyuki Enda, Hiroyoshi Tanimoto, Naoki Kusunokii, Nobutoshi Aoki, Makoto Mizukami, Kiyotaka Miyano, Ichiro Mizushima
  • Publication number: 20060237706
    Abstract: A non-volatile semiconductor memory including a plurality of memory cell transistors, each of the plurality of memory cell transistors includes: a source region having a first conductivity type and in contact with a buried insulating layer on a supporting substrate; a drain-region having the first conductivity type and in contact with the buried insulating layer; and a channel region having the first conductivity type and provided between the source region and the drain region so as to contact the buried insulating layer, wherein a thickness of the channel region is more than one nm and not more than a value obtained by adding seven nm to a half value of a gate length of the memory cell transistor.
    Type: Application
    Filed: April 5, 2006
    Publication date: October 26, 2006
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Toshiyuki Enda, Hiroyoshi Tanimoto, Naoki Kusunoki, Nobutoshi Aoki, Fumitaka Arai, Riichiro Shirota
  • Patent number: 6784006
    Abstract: A method of manufacturing a semiconductor device, comprises: forming a semiconductor element in a semiconductor active region, and calculating the generation rate of electron hole pairs generated due to impact ionization caused in the semiconductor element; calculating a volume integral of the generation rate at least in an area where the impact ionization is caused; evaluating time-dependent degradations of electrical characteristics of the semiconductor element on the basis of the volume integral; and manufacturing a semiconductor device on the basis of the evaluation.
    Type: Grant
    Filed: December 5, 2001
    Date of Patent: August 31, 2004
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroyoshi Tanimoto, Toshiyuki Enda
  • Publication number: 20030073256
    Abstract: A method of manufacturing a semiconductor device, comprises: forming a semiconductor element in a semiconductor active region, and calculating the generation rate of electron hole pairs generated due to impact ionization caused in the semiconductor element; calculating a volume integral of the generation rate at least in an area where the impact ionization is caused; evaluating time-dependent degradations of electrical characteristics of the semiconductor element on the basis of the volume integral; and manufacturing a semiconductor device on the basis of the evaluation.
    Type: Application
    Filed: December 5, 2001
    Publication date: April 17, 2003
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hiroyoshi Tanimoto, Toshiyuki Enda
  • Publication number: 20010025230
    Abstract: The present invention quantitatively estimates how much of each carrier generation and extinction mechanism is contributed to the leak current by a single simulation. Thus, according to the present invention, the time required for evaluating the electric characteristics can be substantially curtailed, and the term and expenses of manufacturing a semiconductor device can be curtailed.
    Type: Application
    Filed: January 30, 2001
    Publication date: September 27, 2001
    Inventor: Hiroyoshi Tanimoto
  • Patent number: 6195790
    Abstract: A &Dgr;Z calculator calculates difference between an inversion layer capacitance by a classical theory and an inversion layer capacitance by a quantum theory, calculates &Dgr;Z which is a thickness of a semiconductor substrate equivalent to the difference in inversion layer capacitance. A discretization mesh generator generates a Delaunay discretization mesh for a structure of the semiconductor device to be evaluated. An electrical parameter calculator calculates electrical parameters of the semiconductor device under constraint that a charge density of channel conductivity type of the semiconductor device is set to zero at discretization mesh points of the discretization mesh on an interface between an insulating film and the semiconductor substrate and at discretization mesh points of the discretization mesh in the semiconductor substrate which are located within a distance less than the stored &Dgr;Z from the interface between the insulating film and the semiconductor substrate.
    Type: Grant
    Filed: April 17, 1998
    Date of Patent: February 27, 2001
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroyoshi Tanimoto, Toshiyuki Enda, Naoyuki Shigyo, Kazuya Matsuzawa
  • Patent number: 5905279
    Abstract: A memory cell having a low storage node resistance and a method of manufacturing the same are provided. A trench type memory cell, in addition to storage node polysilicon, has other conductive material embedded in the storage node. Conductive material may be one of WSi, TiSi, W, Ti, and TiN. The additional conductive material provides a low storage node resistance which facilitates the realization of 256 Mbit memory cells and beyond.
    Type: Grant
    Filed: April 9, 1996
    Date of Patent: May 18, 1999
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akihiro Nitayama, Hiroyoshi Tanimoto
  • Patent number: 5763918
    Abstract: The preferred embodiment of the present invention overcomes the limitations of the prior art and provides a device and method to decrease the latch-up susceptibility of an ESD structure by suppressing the injection of minority carriers that cause transistor action to occur. This is accomplished, for example, by using a metal contact to the n-substrate or n-well in place of or in parallel with the prior art p-diffusion. Using such a metal contact forms a Schottky Barrier Diode (SBD) with the ESD structure. Since the SBD is a majority-carrier device, negligible minority carriers are injected when the SBD is in forward bias, thereby reducing the likelihood of latch-up.
    Type: Grant
    Filed: October 22, 1996
    Date of Patent: June 9, 1998
    Assignee: International Business Machines Corp.
    Inventors: Badih El-Kareh, James Gardner Ryan, Hiroyoshi Tanimoto
  • Patent number: 5463234
    Abstract: A semiconductor memory device, in particular a dynamic random access memory cell which realizes a high speed thereof and presenting a superior controllability. The dynamic random access memory (DRAM) cell includes: a first transistor; a second transistor, electrically connected in series to the first transistor, for storing an electric charge, the second transistor including a portion for erasing the charge stored at the second transistor, wherein the first transistor and the second transistor are electrically connected between a power line and a bit line; and a diode electrically connected between the first transistor and the second transistor.
    Type: Grant
    Filed: March 17, 1995
    Date of Patent: October 31, 1995
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akira Toriumi, Naoyuki Shigyo, Tetsunori Wada, Hiroyoshi Tanimoto, Kazuya Ohuchi, Makoto Yoshimi