Patents by Inventor Toshihiro Kamohara

Toshihiro Kamohara 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).

  • Piezoelectric thin film, piezoelectric material, and fabrication method of piezoelectric thin film and piezoelectric material, and piezoelectric resonator, actuator element, and physical sensor using piezoelectric thin film
    Patent number: 7758979
    Abstract: A piezoelectric thin film of the present invention includes an aluminum nitride thin film that contains scandium. A content ratio of scandium in the aluminum nitride thin film is 0.5 atom % to 50 atom % on the assumption that a total amount of the number of scandium atoms and the number of aluminum atoms is 100 atom %. According to this arrangement, the piezoelectric thin film of the present invention can improve a piezoelectric response while keeping characteristics of elastic wave propagation speed, Q value, and frequency-temperature coefficient that the aluminum nitride thin film has.
    Type: Grant
    Filed: May 29, 2008
    Date of Patent: July 20, 2010
    Assignees: National Institute of Advanced Industrial Science and Technology, DENSO CORPORATION
    Inventors: Morito Akiyama, Toshihiro Kamohara, Naohiro Ueno, Kazuhiko Kano, Akihiko Teshigahara, Yukihiro Takeuchi, Nobuaki Kawahara
  • Wurtzite thin film, laminate containing wurtzite crystalline layer and their manufacturing methods
    Patent number: 7642693
    Abstract: A thin film made of a wurtzite structure compound is manufactured by a reactive sputtering using a metal material as a target, and a nitrogen gas or oxygen gas as a reactive gas. By optimizing film-forming conditions when manufacturing the film, it is possible to obtain a wurtzite thin film whose polarization directions of crystal grains are aligned in a uniform direction. There is provided a laminate including a first wurtzite crystalline layer made of a wurtzite crystalline structure compound is formed in advance between a substrate and a functional material layer that is a ground. Thus it is possible to improve the crystallinity and crystalline orientation of a second wurtzite crystalline layer on the functional material layer.
    Type: Grant
    Filed: May 14, 2004
    Date of Patent: January 5, 2010
    Assignee: National Institute of Advanced Industrial Science and Technology
    Inventors: Morito Akiyama, Naohiro Ueno, Hiroshi Tateyama, Toshihiro Kamohara
  • Piezoelectric thin film, piezoelectric material, and fabrication method of piezoelectric thin film and piezoelectric material, and piezoelectric resonator, actuator element, and physical sensor using piezoelectric thin film
    Publication number: 20080296529
    Abstract: A piezoelectric thin film of the present invention includes an aluminum nitride thin film that contains scandium. A content ratio of scandium in the aluminum nitride thin film is 0.5 atom % to 50 atom % on the assumption that a total amount of the number of scandium atoms and the number of aluminum atoms is 100 atom %. According to this arrangement, the piezoelectric thin film of the present invention can improve a piezoelectric response while keeping characteristics of elastic wave propagation speed, Q value, and frequency-temperature coefficient that the aluminum nitride thin film has.
    Type: Application
    Filed: May 29, 2008
    Publication date: December 4, 2008
    Applicants: NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY, DENSO CORPORATION
    Inventors: Morito Akiyama, Toshihiro Kamohara, Naohiro Ueno, Kazuhiko Kano, Akihiko Teshigahara, Yukihiro Takeuchi, Nobuaki Kawahara
  • Wurtzite thin film, laminate containing wurtzite crystalline layer and their manufacturing methods
    Publication number: 20070057285
    Abstract: According to the present invention, a thin film made of a wurtzite structure compound is manufactured by a reactive sputtering using a metal material as a target, and a nitrogen gas or an oxygen gas as a reactive gas. By optimizing film-forming conditions when manufacturing the film, it is possible to obtain a wurtzite thin film whose polarization directions of crystal grains are aligned in a uniform direction. According to a laminate of the present invention, a first wurtzite crystalline layer made of a wurtzite crystalline structure compound is formed in advance between a substrate and a functional material layer that is a ground. Thus, it is possible to improve the crystallinity and crystalline orientation of a second wurtzite crystalline layer formed on the functional material layer.
    Type: Application
    Filed: May 14, 2004
    Publication date: March 15, 2007
    Inventors: Morito Akiyama, Naohiro Ueno, Hiroshi Tateyama, Toshihiro Kamohara