Patents by Inventor Kunihiro Kasai

Kunihiro Kasai 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: 7687368
    Abstract: A semiconductor device manufacturing method is disclosed. The method is to form a second semiconductor layer which has less susceptibility to adopting insulative characteristics than a first semiconductor layer on the first semiconductor layer. Then, grooves which expose portions of the second and first semiconductor layers are formed to extend from the upper surface of the second semiconductor layer into the first semiconductor layer. Next, portions of the first and second semiconductor layers which are exposed to the grooves are changed into an insulator form to fill the grooves with the insulator-form portions of the first semiconductor layer.
    Type: Grant
    Filed: March 25, 2005
    Date of Patent: March 30, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hirohisa Kawasaki, Kazunari Ishimaru, Kunihiro Kasai, Yasunori Okayama
  • Publication number: 20050282354
    Abstract: A semiconductor device manufacturing method is disclosed. The method is to form a second semiconductor layer which has less susceptibility to adopting insulative characteristics than a first semiconductor layer on the first semiconductor layer. Then, grooves which expose portions of the second and first semiconductor layers are formed to extend from the upper surface of the second semiconductor layer into the first semiconductor layer. Next, portions of the first and second semiconductor layers which are exposed to the grooves are changed into an insulator form to fill the grooves with the insulator-form portions of the first semiconductor layer.
    Type: Application
    Filed: March 25, 2005
    Publication date: December 22, 2005
    Inventors: Hirohisa Kawasaki, Kazunari Ishimaru, Kunihiro Kasai, Yasunori Okayama
  • Patent number: 6624514
    Abstract: A semiconductor device includes a middle inter-level insulating film disposed on or above a semiconductor substrate, a conductive layer disposed on the middle inter-level insulating film, and an upper inter-level insulating film disposed on the middle inter-level insulating film and the conductive layer. The upper inter-level insulating film includes first, second, and third wiring grooves distant from each other. The second and third wiring grooves use the conductive layer as their bottoms. The side surfaces of the first, second, and third wiring grooves are covered with in-groove barrier layers. First, second, and third wiring layers are buried in the first, second, and third wiring grooves. The first, second, and third wiring layers are derived from the same wiring film, and have a thickness larger than that of the conductive layer. The second and third wiring layers are electrically connected to the conductive layer.
    Type: Grant
    Filed: December 5, 2001
    Date of Patent: September 23, 2003
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Kunihiro Kasai
  • Publication number: 20030102530
    Abstract: The object of the present invention is to provide a semiconductor wafer in which a diffusion of Cu generated by a thermal treatment such as a Cu wiring formation step into silicon is prevented, and variations of transistor characteristics are lessened. The object of the present invention is to provide a method of manufacturing the same and a semiconductor device formed from the same.
    Type: Application
    Filed: January 6, 2003
    Publication date: June 5, 2003
    Applicant: Kabushiki Kaisha Toshiba.
    Inventors: Masahiko Matsumoto, Hisato Oyamatsu, Takeo Nakayama, Yasuhiro Fukaura, Kunihiro Kasai, Masahiro Inohara
  • Patent number: 6525402
    Abstract: The object of the present invention is to provide a semiconductor wafer in which a diffusion of Cu generated by a thermal treatment such as a Cu wiring formation step into silicon is prevented, and variations of transistor characteristics are lessened. The object of the present invention is to provide a method of manufacturing the same and a semiconductor device formed from the same. In the present invention, a protection insulating film for preventing Cu from diffusing into the inside of the wafer is formed on a peripheral portion of a principal plane, a external side plane and a rear plane of the wafer. With this protection insulating film, the diffusion of Cu that is a wiring material into a chip formation region of the wafer is prevented, so that the variations of the transistor characteristic.
    Type: Grant
    Filed: September 14, 1999
    Date of Patent: February 25, 2003
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masahiko Matsumoto, Hisato Oyamatsu, Takeo Nakayama, Yasuhiro Fukaura, Kunihiro Kasai, Masahiro Inohara
  • Publication number: 20020084526
    Abstract: A semiconductor device includes a middle inter-level insulating film disposed on or above a semiconductor substrate, a conductive layer disposed on the middle inter-level insulating film, and an upper inter-level insulating film disposed on the middle inter-level insulating film and the conductive layer. The upper inter-level insulating film includes first, second, and third wiring grooves distant from each other. The second and third wiring grooves use the conductive layer as their bottoms. The side surfaces of the first, second, and third wiring grooves are covered with in-groove barrier layers. First, second, and third wiring layers are buried in the first, second, and third wiring grooves. The first, second, and third wiring layers are derived from the same wiring film, and have a thickness larger than that of the conductive layer. The second and third wiring layers are electrically connected to the conductive layer.
    Type: Application
    Filed: December 5, 2001
    Publication date: July 4, 2002
    Inventor: Kunihiro Kasai
  • Patent number: 6388304
    Abstract: The present invention is a semiconductor device having an element isolation structure of STI, in which after the formation of the STI trench, a silicon nitride film is left over only on the side wall portion of the trench, to form a side wall. Further, ions are implanted from the bottom surface of the trench on which the side wall is formed, and thus a high-concentration punch-through suppression region having the same conductivity as that of the substrate (or well) and a concentration higher that the impurity concentration of the other section close to the substrate (or well), is formed selectively only in the section of the substrate (or well) which is near the bottom surface of the trench. In this manner, the punch-through suppression region can be formed only in the bottom portion of the STI in a self-alignment manner by the thickness of the side wall.
    Type: Grant
    Filed: April 27, 2001
    Date of Patent: May 14, 2002
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Fumitomo Matsuoka, Kunihiro Kasai
  • Publication number: 20010028097
    Abstract: The present invention is a semiconductor device having an element isolation structure of STI, in which after the formation of the STI trench, a silicon nitride film is left over only on the side wall portion of the trench, to form a side wall. Further, ions are implanted from the bottom surface of the trench on which the side wall is formed, and thus a high-concentration punch-through suppression region having the same conductivity as that of the substrate (or well) and a concentration higher that the impurity concentration of the other section close to the substrate (or well), is formed selectively only in the section of the substrate (or well) which is near the bottom surface of the trench. In this manner, the punch-through suppression region can be formed only in the bottom portion of the STI in a self-alignment manner by the thickness of the side wall.
    Type: Application
    Filed: April 27, 2001
    Publication date: October 11, 2001
    Inventors: Fumitomo Matsuoka, Kunihiro Kasai
  • Patent number: 6248645
    Abstract: The present invention is a semiconductor device having an element isolation structure of STI, in which after the formation of the STI trench, a silicon nitride film is left over only on the side wall portion of the trench, to form a side wall. Further, ions are implanted from the bottom surface of the trench on which the side wall is formed, and thus a high-concentration punch-through suppression region having the same conductivity as that of the substrate (or well) and a concentration higher that the impurity concentration of the other section close to the substrate (or well), is formed selectively only in the section of the substrate (or well) which is near the bottom surface of the trench. In this manner, the punch-through suppression region can be formed only in the bottom portion of the STI in a self-alignment manner by the thickness of the side wall.
    Type: Grant
    Filed: May 27, 1999
    Date of Patent: June 19, 2001
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Fumitomo Matsuoka, Kunihiro Kasai
  • Patent number: 6197648
    Abstract: A gate electrode is formed in an element region of a semiconductor substrate. By ion implantation using the gate electrode as the mask, a low density doping (LDD) region is formed. By ion implantation after forming a side wall insulating film on the side wall of the gate electrode, source and drain regions are formed. Afterwards, by varying the thickness of the side wall insulating film of the side wall of the gate electrode, that is, by reducing the thickness of the side wall insulating film, a sufficient silicide region is formed on the source and drain regions. A silicide layer is formed on the gate electrode and source and drain regions by thermal reaction between a refractory metal and silicon in the gate electrode or in the semi-conductor substrate.
    Type: Grant
    Filed: September 9, 1998
    Date of Patent: March 6, 2001
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kunihiro Kasai, Hisato Oyamatsu
  • Patent number: 6008061
    Abstract: A method for manufacturing a surface mounting type semiconductor device, to prevent a bump from forming on a test pad, by contacting with a probe needle at a die sort test in manufacturing a surface mounting type semiconductor device. A test pad is formed with a layer, made of the same components as a bonding pad, above the major surface of semiconductor substrate, where an IC is formed. A probe needle is applied onto the test pad to carry out a die sort test. Subsequently, for a conforming article, a resist film is patterned by a lithography technique, thus removing only the test pad. A bump is normally formed only on the remaining bonding pad, thereby avoiding a continuity failure at assembly and any unexpected short-circuits during the connection with the wiring.
    Type: Grant
    Filed: October 10, 1997
    Date of Patent: December 28, 1999
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Kunihiro Kasai
  • Patent number: 5410165
    Abstract: A thin film transistor includes a semiconductor thin film formed with a source region and a drain region at opposite end portions thereof and having an offset region near at the drain region, a gate electrode formed above the region between the source region and the offset region of the semiconductor thin film, with a gate insulating film being interposed, and a conductive layer formed above the gate electrode or under the semiconductor thin film, with an insulating film being interposed, the conductive layer being applied with generally the same potential as the gate electrode, wherein the resistance value of the offset region is controlled by the potential of the conductive layer. The gate electrode may be formed under the semiconductor thin film. In this case, the conductive layer is formed above the semiconductor thin film or under the gate electrode, with an insulating film being interposed. An SRAM is also provided which uses a thin film transistor constructed as above.
    Type: Grant
    Filed: May 25, 1993
    Date of Patent: April 25, 1995
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Kunihiro Kasai