Patents by Inventor Yusuke Kohyama

Yusuke Kohyama 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: 6979866
    Abstract: In the SOI region of a semiconductor substrate, a BOX layer is formed underneath with backgate electrodes to control the threshold voltages of MOS transistors formed in the SOI region.
    Type: Grant
    Filed: September 3, 2003
    Date of Patent: December 27, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Atsushi Azuma, Yusuke Kohyama, Kaori Umezawa
  • Patent number: 6977228
    Abstract: A gate insulation film is formed on a semiconductor substrate, gate electrodes are formed on the gate insulation film, and source/drain diffusion layers are formed. A silicon nitride films is formed on a side wall of the gate electrodes, a silicon oxide film is formed on the overall surface, and the silicon oxide film is etched back to have the same height as that of the gate electrodes so that the surface is flattened, and then the surface of the gate electrodes are etched by a predetermined thickness to form a first stepped portion from the silicon oxide film, the first stepped portion is filled up by a tungsten film, the surface of the tungsten film is etched by a predetermined thickness so that a second stepped portion is formed, and then the second stepped portion is filled by a silicon nitride films.
    Type: Grant
    Filed: March 17, 2003
    Date of Patent: December 20, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yusuke Kohyama, Nobuo Hayasaka, Katsuya Okumura
  • Publication number: 20050258485
    Abstract: An isolated semiconductor device and method for producing the isolated semiconductor device in which the device includes a silicon-on-insulator (SOI) device formed on a substrate. A dielectric film is formed on the insulator and covers the SOI device. The dielectric film may be a single film or a multilayer film. The silicon layer of the SOI device may include a channel region and source/drain regions. The SOI device may further include a gate insulator disposed on the channel region of the silicon layer, a gate disposed on the gate insulator and sidewall spacers formed a side surface of the gate. The dielectric film may also be disposed on an edge portion of the silicon layer. The device structure may further include metallization lines connecting through the isolation dielectric to the gate and to the source/drain regions.
    Type: Application
    Filed: May 21, 2004
    Publication date: November 24, 2005
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Yusuke Kohyama
  • Publication number: 20050206002
    Abstract: In a semiconductor device, a wiring pattern groove is formed in a surface portion of a silicon oxide film provided above a semiconductor substrate. A wiring layer is buried into the wiring pattern groove with a barrier metal film interposed therebetween. The barrier metal film is selectively removed from each sidewall portion of the wiring pattern groove. In other words, the barrier metal film is left only on the bottom of the wiring pattern groove. Thus, a damascene wiring layer having a hollow section whose dielectric constant is low between each sidewall of the wiring pattern groove and each side of the wiring layer can be formed in the semiconductor device.
    Type: Application
    Filed: May 5, 2005
    Publication date: September 22, 2005
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Hiroyuki Nitta, Yoshiaki Fukuzumi, Yusuke Kohyama
  • Patent number: 6906419
    Abstract: In a semiconductor device, a wiring pattern groove is formed in a surface portion of a silicon oxide film provided above a semiconductor substrate. A wiring layer is buried into the wiring pattern groove with a barrier metal film interposed therebetween. The barrier metal film is selectively removed from each sidewall portion of the wiring pattern groove. In other words, the barrier metal film is left only on the bottom of the wiring pattern groove. Thus, a damascene wiring layer having a hollow section whose dielectric constant is low between each sidewall of the wiring pattern groove and each side of the wiring layer can be formed in the semiconductor device.
    Type: Grant
    Filed: June 19, 2001
    Date of Patent: June 14, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroyuki Nitta, Yoshiaki Fukuzumi, Yusuke Kohyama
  • Publication number: 20050023696
    Abstract: In a semiconductor device, a wiring pattern groove is formed in a surface portion of a silicon oxide film provided above a semiconductor substrate. A wiring layer is buried into the wiring pattern groove with a barrier metal film interposed therebetween. The barrier metal film is selectively removed from each sidewall portion of the wiring pattern groove. In other words, the barrier metal film is left only on the bottom of the wiring pattern groove. Thus, a damascene wiring layer having a hollow section whose dielectric constant is low between each sidewall of the wiring pattern groove and each side of the wiring layer can be formed in the semiconductor device.
    Type: Application
    Filed: August 27, 2004
    Publication date: February 3, 2005
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Hiroyuki Nitta, Yoshiaki Fukuzumi, Yusuke Kohyama
  • Patent number: 6846733
    Abstract: First and second wirings are formed on a first insulating film. Each of the wirings is arranged so that a conductive film, a silicon oxide film and a silicon nitride film are laminated. Thereafter, a silicon oxide insulating film is formed on the whole surface. The silicon oxide insulating film is etched so that a contact hole is formed between the first and second wirings. Since the silicon oxide film and the silicon nitride film exist on the conductive film of each wiring, the conductive film is not exposed at the time of etching. Thereafter, an insulating film is formed on a side wall of the contact hole, and the conductive film exposed through the contact hole is covered by the insulating film.
    Type: Grant
    Filed: March 17, 2003
    Date of Patent: January 25, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yusuke Kohyama, Takashi Ohsawa, Shizuo Sawada
  • Publication number: 20040262771
    Abstract: First and second wirings are formed on a first insulating film. Each of the wirings is arranged so that a conductive film, a silicon oxide film and a silicon nitride film are laminated. Thereafter, a silicon oxide insulating film is formed on the whole surface. The silicon oxide insulating film is etched so that a contact hole is formed between the first and second wirings. Since the silicon oxide film and the silicon nitride film exist on the conductive film of each wiring, the conductive film is not exposed at the time of etching. Thereafter, an insulating film is formed on a side wall of the contact hole, and the conductive film exposed through the contact hole is covered by the insulating film.
    Type: Application
    Filed: July 20, 2004
    Publication date: December 30, 2004
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Yusuke Kohyama, Takashi Ohsawa, Shizuo Sawada
  • Publication number: 20040227260
    Abstract: A first concave portion for the element isolation, a second concave portion for an aligning mark, and a third concave portion for an anti-fuse portion are formed simultaneously within a silicon substrate. After a silicon oxide film is formed on the entire surface, the silicon oxide film positioned within the second and third concave portions is removed. Then, a gate insulating film is formed on the entire surface, followed by forming a polysilicon film on the gate insulating film. Further, these polysilicon film and gate insulating film are selectively removed to form a gate electrode above an element region, an aligning mark portion in the second concave portion, and a gate electrode for an anti-fuse portion on the bottom surface of the third concave portion.
    Type: Application
    Filed: June 22, 2004
    Publication date: November 18, 2004
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Yoshiaki Fukuzumi, Yusuke Kohyama
  • Patent number: 6812542
    Abstract: A semiconductor device comprises capacitor structures, each having a first lower electrode, a first insulating film formed on the first lower electrode and a first upper electrode formed on the first insulating film, and electric fuse elements, each having a second lower electrode, a second insulating film formed on the second lower electrode and having an impurity concentration higher than that of the first insulating film, and a second upper electrode formed on the second insulating film. The electric fuse elements have substantially the same structure as that of the capacitor structures, and they are formed on the same level as that of the capacitor structures. A writing voltage of the electric fuse element is determined by dielectric breakdown resistance of the second insulating film, which depends on the impurity concentration of the second insulating film.
    Type: Grant
    Filed: June 28, 2001
    Date of Patent: November 2, 2004
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yusuke Kohyama
  • Patent number: 6774439
    Abstract: A first concave portion for the element isolation, a second concave portion for an aligning mark, and a third concave portion for an anti-fuse portion are formed simultaneously within a silicon substrate. After a silicon oxide film is formed on the entire surface, the silicon oxide film positioned within the second and third concave portions is removed. Then, a gate insulating film is formed on the entire surface, followed by forming a polysilicon film on the gate insulating film. Further, these polysilicon film and gate insulating film are selectively removed to form a gate electrode above an element region, an aligning mark portion in the second concave portion, and a gate electrode for an anti-fuse portion on the bottom surface of the third concave portion.
    Type: Grant
    Filed: February 15, 2001
    Date of Patent: August 10, 2004
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshiaki Fukuzumi, Yusuke Kohyama
  • Publication number: 20040124439
    Abstract: A hollow region is formed in a silicon substrate. A plurality of openings formed in the silicon layer on the hollow region is filled with a buried film. The bottom portion of the hollow region is formed with a plurality of silicon pillars, which support the silicon layer.
    Type: Application
    Filed: September 4, 2003
    Publication date: July 1, 2004
    Inventors: Yoshihiro Minami, Takashi Yamada, Yusuke Kohyama, Tsutomu Sato, Hajime Nagano
  • Publication number: 20040108552
    Abstract: In the SOI region of a semiconductor substrate, a BOX layer is formed underneath with backgate electrodes to control the threshold voltages of MOS transistors formed in the SOI region.
    Type: Application
    Filed: September 3, 2003
    Publication date: June 10, 2004
    Inventors: Atsushi Azuma, Yusuke Kohyama, Kaori Umezawa
  • Patent number: 6720606
    Abstract: A semiconductor memory device has a semiconductor substrate, a first semiconductor region of a first conduction type formed on the semiconductor substrate, a second semiconductor region of a second conduction type opposite to the first conduction type, formed on the first semiconductor region. A trench capacitors having a trench extends through the first semiconductor region and the second semiconductor region, and is formed such that its top does not reach a top surface of the second semiconductor region, and the trench is formed therein with a conductive trench fill. A pair of gate electrodes is formed on the second semiconductor region, overlying the trench capacitor. A pair of insulating layers is formed to cover each of the pair of gate electrodes. A conductive layer is formed between the pair of insulating layers to self-align to each of the pair of insulating layers.
    Type: Grant
    Filed: September 12, 2000
    Date of Patent: April 13, 2004
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akihiro Nitayama, Katsuhiko Hieda, Shigeru Ishibashi, Yusuke Kohyama
  • Patent number: 6635933
    Abstract: Capacitors are formed in the trenches made in an interlayer insulator made of silicon oxide. An insulating film (e.g., a silicon nitride film) is provided on the sides of each trench of the interlayer insulator. A storage electrode made of ruthenium or the like is provided in each trench of the interlayer insulator. A capacitor insulating film made of BSTO or the like is formed on the storage electrode. A plate electrode made of ruthenium or the like is formed on the capacitor insulating film. The plate electrode is common to all capacitors provided. Any two adjacent capacitors are electrically isolated by the interlayer insulator and the insulating film provided on the sides of the trenches of the interlayer insulator.
    Type: Grant
    Filed: September 17, 2001
    Date of Patent: October 21, 2003
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yutaka Ishibashi, Yusuke Kohyama, Tohru Ozaki
  • Publication number: 20030178686
    Abstract: First and second wirings are formed on a first insulating film. Each of the wirings is arranged so that a conductive film, a silicon oxide film and a silicon nitride film are laminated. Thereafter, a silicon oxide insulating film is formed on the whole surface. The silicon oxide insulating film is etched so that a contact hole is formed between the first and second wirings. Since the silicon oxide film and the silicon nitride film exist on the conductive film of each wiring, the conductive film is not exposed at the time of etching. Thereafter, an insulating film is formed on a side wall of the contact hole, and the conductive film exposed through the contact hole is covered by the insulating film.
    Type: Application
    Filed: March 17, 2003
    Publication date: September 25, 2003
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Yusuke Kohyama, Takashi Ohsawa, Shizuo Sawada
  • Publication number: 20030162396
    Abstract: A gate insulation film is formed on a semiconductor substrate, gate electrodes are formed on the gate insulation film, and source/drain diffusion layers are formed. A silicon nitride films is formed on a side wall of the gate electrodes, a silicon oxide film is formed on the overall surface, and the silicon oxide film is etched back to have the same height as that of the gate electrodes so that the surface is flattened, and then the surface of the gate electrodes are etched by a predetermined thickness to form a first stepped portion from the silicon oxide film, the first stepped portion is filled up by a tungsten film, the surface of the tungsten film is etched by a predetermined thickness so that a second stepped portion is formed, and then the second stepped portion is filled by a silicon nitride films.
    Type: Application
    Filed: March 17, 2003
    Publication date: August 28, 2003
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Yusuke Kohyama, Nobuo Hayasaka, Katsuya Okumura
  • Patent number: 6608356
    Abstract: A gate insulation film is formed on semiconductor substrate, a gate electrodes are formed on the gate insulation film, and source/drain diffusion layers are formed. Silicon nitride films are formed on a side wall of the gate electrodes, a silicon oxide film is formed on the overall surface, and the silicon oxide film is etched back to have the same height as that of the gate electrodes so that the surface is flattened, and then the surface of the gate electrodes are etched by a predetermined thickness to form a first stepped portion from the silicon oxide film, the first stepped portion is filled up by a tungsten film, the surface of the tungsten film is etched by a predetermined thickness so that a second stepped portion is formed, and then the second stepped portion is filled by a silicon nitride film.
    Type: Grant
    Filed: July 14, 1997
    Date of Patent: August 19, 2003
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yusuke Kohyama, Nobuo Hayasaka, Katsuya Okumura
  • Patent number: 6593202
    Abstract: In a method of fabricating a COB DRAM cell, a polysilicon plug is formed on the source and drain in self-alignment with the gate electrode. A bit line contact and a storage electrode contact are formed on the polysilicon plug thereby to reduce the aspect ratio of both the bit line contact and the storage electrode contact. With the polysilicon plug formed in self-alignment with the gate electrode, short-circuiting of contacts of adjacent element regions and short-circuiting of the plugs of the source and drain will not occur, leading to high protection against misregistration. Moreover, an independent lithography process is not required for forming the polysilicon plug, and, therefore, the number of fabrication steps is reduced.
    Type: Grant
    Filed: July 23, 2001
    Date of Patent: July 15, 2003
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Keiji Hosotani, Yusuke Kohyama
  • Publication number: 20030094645
    Abstract: Disclosed is a semiconductor device having a structure capable of restraining deterioration of a dielectric film (BSTO) of a capacitor even when annealing is performed in a hydrogen-containing atmosphere. This semiconductor device comprises a plurality of dispersion electrodes (SRO) formed in a dispersed manner above a semiconductor substrate, and a common electrode commonly facing the dispersion electrodes via respective dielectric films (BSTO). This common electrode includes a lower conductive layer (SRO) formed on the dielectric films, a barrier layer (Al2O3) formed on the lower conductive layer and an upper conductive layer (Al) formed on the barrier layer.
    Type: Application
    Filed: January 2, 2003
    Publication date: May 22, 2003
    Inventors: Yoshiaki Fukuzumi, Yusuke Kohyama