Patents by Inventor Jumpei Kumagai

Jumpei Kumagai 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: 5561308
    Abstract: A semiconductor device comprises a semiconductor substrate of a first conductivity type, a first insulation film formed on the semiconductor substrate, a gate electrode and a second insulation film formed in sequence on the first insulation film, a trench being formed to extend through the second insulation film, the gate electrode and the first insulation film to an interior of the semiconductor substrate. A cylindrical gate insulation film is formed on a surface of the gate electrode which is exposed in the trench. A capacitor insulation film is formed on a surface of the semiconductor substrate exposed in the trench. A cylindrical conductive film is formed inside these insulation films.
    Type: Grant
    Filed: December 30, 1994
    Date of Patent: October 1, 1996
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideyuki Kamata, Jumpei Kumagai
  • Patent number: 5430313
    Abstract: At the surface of a p-type silicon substrate, n-type source/drain diffused layers are formed. On the substrate between the source/drain diffused layers, a gate insulating film made of a silicon oxide film is formed so as to be isolated from the diffused layers. A gate electrode is formed on the gate insulating film. Sidewalls are formed on the sides of the gate insulating film and gate electrode, extending upward from the substrate. In this invention, the sidewalls are composed of material whose permittivity is higher than that of the gate insulating film, for example, of a silicon nitride film.
    Type: Grant
    Filed: March 30, 1994
    Date of Patent: July 4, 1995
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Jumpei Kumagai, Tomohisa Mizuno
  • Patent number: 5324975
    Abstract: For increasing pattern density of cell regions in a semiconductor memory device including an array of dynamic memory cells, the cell regions for cell transistor pairs are provided in a semiconductor substrate so as to be crossed by one desired bit line and two word lines adjacent thereto, and the patterns of cell regions have a same direction. Contacts for electrically connecting each bit line to common regions of cell transistor pairs are provided on respective bit lines every desired pitch at positions where each bit line intersects with cell regions. These contacts of adjacent bit lines are successively shifted in a bit line direction by approximately 1/2.sup.n (n is natural numbers greater than or equal to 2) pitch.
    Type: Grant
    Filed: January 14, 1993
    Date of Patent: June 28, 1994
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Jumpei Kumagai, Shizuo Sawada
  • Patent number: 5321300
    Abstract: In a laser-broken fuse used in a memory redundancy technique, an aluminum wiring layer is formed on an interlevel insulating film. A portion of the wiring layer is selected to be broken to shut off conduction of the layer. A polysilicon-made heat member is provided in the interlevel insulating film at the place which is underneath the selected portion. The heat member is located on a field insulating film. This heat member generates heat by absorbing energy from a laser beam, and thermal-explodes in a sealed atmosphere so as to break the selected portion.
    Type: Grant
    Filed: April 8, 1992
    Date of Patent: June 14, 1994
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshio Usuda, Hiroaki Itaba, Jumpei Kumagai, Seiji Kaki
  • Patent number: 5302845
    Abstract: At the surface of a p-type silicon substrate, n-type source/drain diffused layers are formed. On the substrate between the source/drain diffused layers, a gate insulating film made of a silicon oxide film is formed so as to be isolated from the diffused layers. A gate electrode is formed on the gate insulating film. Sidewalls are formed on the sides of the gate insulating film and gate electrode, extending upward from the substrate. In this invention, the sidewalls are composed of material whose permittivity is higher than that of the gate insulating film, for example, of a silicon nitride film.
    Type: Grant
    Filed: September 15, 1993
    Date of Patent: April 12, 1994
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Jumpei Kumagai, Tomohisa Mizuno
  • Patent number: 5276343
    Abstract: A DRAM cell having a bit line constituted by a semiconductor layer. The DRAM cell comprises a semiconductor substrate of a first conductivity type having a main surface, an insulating film formed on the main surface, an opening formed in the insulating film to communicate with the substrate, and a bit line formed by a semiconductor layer of a second conductivity type formed on the insulating film and that portion of the substrate which is exposed through the opening.
    Type: Grant
    Filed: September 10, 1992
    Date of Patent: January 4, 1994
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Jumpei Kumagai, Shizuo Sawada
  • Patent number: 5194752
    Abstract: For increasing pattern density of cell regions in a semiconductor memory device including an array of dynamic memory cells, the cell regions for cell transistor pairs are provided in a semiconductor substrate so as to be crossed by one desired bit line and two word lines adjacent thereto, and the patterns of cell regions have a same direction. Contacts for electrically connecting each bit line to common regions of cell transistor pairs are provided on respective bit lines every desired pitch at positions where each bit line intersects with cell regions. These contacts of adjacent bit lines are successively shifted in a bit line direction by approximately 1/2.sup.n pitch (n is natural numbers greater than or equal to 2).
    Type: Grant
    Filed: December 23, 1991
    Date of Patent: March 16, 1993
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Jumpei Kumagai, Shizuo Sawada
  • Patent number: 5041887
    Abstract: In one-transistor.one-capacitor type dynamic memory cell, cell capacitor with a reduced junction leakage current comprises a MOS capacitor which is provided between a semiconductor substrate and a charge storage electrode disposed at a side wall of a trench through a first insulating film, and a stacked capacitor which is provided between the charge storage electrode and a capacitor plate electrode formed on a second insulating film covering the entire surface of the charge storage electrode. The equivalent silicon dioxide thickness of the first insulating film is thicker than that of the second insulating film, and the storage capacitance of the cell capacitor is rendered by a sum of the capacitance of the MOS capacitor and the capacitance of the stacked capacitor because these capacitors are electrically connected in parallel with each other.
    Type: Grant
    Filed: May 14, 1990
    Date of Patent: August 20, 1991
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Jumpei Kumagai, Shizuo Sawada
  • Patent number: 5016071
    Abstract: Element regions which are adjacent to each other in a channel width direction are displaced from each other in a channel length direction by 1/4 pitch. Cell plate electrodes are formed over the element regions through a capacitor insulation film to extend in an oblique direction. Groove portions formed in a step-form corresponding to the shape of the respective transistor forming regions of the element regions are each formed between corresponding two adjacent ones of the cell plate electrodes. Word lines are formed in a stripe configuration to extend in a channel width direction and used to directly apply potentials to the element regions. Contact holes are formed for contact hole opening preparation regions of the element regions. Bit lines are formed in a stripe configuration to extend in a length width direction and are connected to respective element regions (1) via the contact holes.
    Type: Grant
    Filed: September 7, 1989
    Date of Patent: May 14, 1991
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Jumpei Kumagai, Syuso Fujii
  • Patent number: 5013679
    Abstract: In a cell capacitor of a dynamic random access memory cell according to the present invention, an insulation film is formed on the surface of a fine trench formed in a silicon semiconductor substrate. A contact hole is formed in the insulation film in a region on the side wall of the trench. A polysilicon film is formed on the side wall of the trench in a hollow-cylindrical shape. A silicon layer is epitaxially and selectively grown on the polysilicon film and on the silicon substrate exposed through the contact hole. The polysilicon film and the silicon layer constitute an information storage electrode. At least the silicon layer of the information storage electrode is electrically connected to a source or a drain region of a transfer transistor of the memory cell. A gate insulation film is formed on the surface of the silicon layer. A counter electrode is formed such that the counter electrode is embedded in the trench.
    Type: Grant
    Filed: September 5, 1989
    Date of Patent: May 7, 1991
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Jumpei Kumagai, Susumu Yoshikawa
  • Patent number: 4950617
    Abstract: This invention discloses a semiconductor integrated circuit in which an input protecting circuit and an inner circuit are formed on a single semiconductor substrate and a MOS transistor of the inner circuit is formed by mask-alignment. The source and drain regions of the MOS transistor of the input protecting circuit are formed by self-alignment, so that the impurity concentration of the source and drain regions is increased and the diffusion resistance thereof is reduced, thereby increasing the junction breakdown power caused by a drain current. In addition, the radii of curvature of the junction curved surface portions of the source and drain regions of the MOS transistor of the input protecting circuit are increased so as to reduce the electric field intensity at the junction curved surface portions, thereby improving the junction breakdown withstand characteristics.
    Type: Grant
    Filed: January 12, 1989
    Date of Patent: August 21, 1990
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Jumpei Kumagai, Satoshi Shinozaki
  • Patent number: 4941031
    Abstract: A signal line runs in parallel with first to fourth bit lines on a memory cell array of a dynamic memory device. The signal line runs between and along the first and third bit lines, turns at a predetermined position, turns again and runs between and along the second and fourth bit lines. The predetermined turning position is a position corresponding to the half of the bit line length. The result is that the stray capacitances between the signal line and these bit lines are equal at about 1/2C.sub.F.
    Type: Grant
    Filed: October 3, 1989
    Date of Patent: July 10, 1990
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Jumpei Kumagai, Syuso Fujii