Patents by Inventor Keigo Nagao

Keigo Nagao 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).

  • Publication number: 20050093397
    Abstract: A pit (52) is formed in a substrate comprising a silicon wafer (51) on a surface of which a silicon oxide thin layer (53) is formed. A sandwich structure (60) comprising a piezoelectric layer (62) and lower and upper electrodes (61, 63) joined to both surfaces of the piezoelectric layer is disposed so as to stride over the pit (52). The upper surface of the lower electrode (61) and the lower surface of the piezoelectric layer (62) joined to the upper surface of the lower electrode are treated so that the RMS variation of the height thereof is equal to 25 nm or less. The thickness of the lower electrode (61) is set to 150 nm or less. According to such a structure, there is provided a high-performance thin film bulk acoustic resonator which are excellent in electromechanical coupling coefficient and acoustic quality factor.
    Type: Application
    Filed: November 23, 2004
    Publication date: May 5, 2005
    Inventors: Tetsuo Yamada, Keigo Nagao, Chisen Hashimoto
  • Patent number: 6885260
    Abstract: A transmission band filter (110) having a series of elements (111, 113, 115) each composed of a film bulk acoustic resonator and grounded shunt elements (112, 114) each composed of a film bulk acoustic resonator is connected between a transmission port (102) and an antenna port (106). A reception band filter (130) having a series of elements (131, 133, 135) each composed of a film bulk acoustic resonator and grounded shunt elements (132, 134, 136) each composed of a film bulk acoustic resonator is connected between a reception port (104) and the antenna port (106). A film bulk acoustic resonator (150) for adjustment is connected between the antenna port (106) and the ground. The resonance frequency of the adjusting film bulk acoustic resonator (150) lies between the upper limit frequency of the transmission frequency pass band of the transmission band filter (110) and the lower limit frequency of the reception frequency pass band of the reception band filter (130).
    Type: Grant
    Filed: May 10, 2002
    Date of Patent: April 26, 2005
    Assignee: UBE Industries, Ltd.
    Inventors: Kosuke Nishimura, Keigo Nagao, Chisen Hashimoto, Eiji Masui, Hirofumi Kimura
  • Patent number: 6842088
    Abstract: A pit (52) is formed in a substrate comprising a silicon wafer (51) on a surface of which a silicon oxide thin layer (53) is formed. A sandwich structure (60) comprising a piezoelectric layer (62) and lower and upper electrodes (61, 63) joined to both surfaces of the piezoelectric layer is disposed so as to stride over the pit (52). The upper surface of the lower electrode (61) and the lower surface of the piezoelectric layer (62) joined to the upper surface of the lower electrode are treated so that the RMS variation of the height thereof is equal to 25 nm or less. The thickness of the lower electrode (61) is set to 150 nm or less. According to such a structure, there is provided a high-performance thin film bulk acoustic resonator which are excellent in electromechanical coupling coefficient and acoustic quality factor.
    Type: Grant
    Filed: May 9, 2002
    Date of Patent: January 11, 2005
    Assignee: Ube Industries, Ltd.
    Inventors: Tetsuo Yamada, Keigo Nagao, Chisen Hashimoto
  • Publication number: 20040135144
    Abstract: A thin film bulk acoustic resonator comprises a substrate (12) of a silicon single crystal, a base film (13) formed on the substrate (12) and composed of a dielectric film mainly containing silicon oxide, and a piezoelectric stacked structure (14) formed on the base film (13). A vibratory section (21) composed of a part of the base film (13) and a part of the piezoelectric stacked structure (14). The piezoelectric stacked structure (14) includes a lower electrode (15), a piezoelectric film (16), and an upper electrode (17) formed in this order from below. The substrate (12) had a via hole (20) in the region corresponding to the vibratory section (21). The via hole forms a space for allowing vibration of the vibratory section (21). The piezoelectric film (16) is an aluminum nitride thin film containing 0.2 to 3.0 atom % of alkaline earth metal and/or a rare earth metal.
    Type: Application
    Filed: November 10, 2003
    Publication date: July 15, 2004
    Inventors: Tetsuo Yamada, Keigo Nagao, Chisen Hashimoto, Morito Akiyama, Naohiro Ueno, Hiroshi Tateyama
  • Publication number: 20040137061
    Abstract: The present invention provides a process for producing an orally fast disintegrating preparation containing functional particles, which comprises filling in a mold an aqueous dispersion containing (a) a dispersant showing a dispersion maintaining ratio of about 75% or more and a viscosity of about 100 mPa.s or less at 25° C. in case of being contained homogeneously in water at 1% by weight, (b) a water-soluble saccharide, and (c) functional particles; and then removing water; and an orally fast disintegrating preparation containing functional particles, which comprises (a) a dispersant showing a dispersion maintaining ratio of 75% or more and a viscosity of 100 mPa.s or less at 25° C. in case of being contained homogeneously in water at 1% by weight, (b) a water-soluble saccharide, and (c) functional particles.
    Type: Application
    Filed: December 5, 2003
    Publication date: July 15, 2004
    Inventors: Takashi Ishibashi, Keigo Nagao, Kosuke Kiyomizu
  • Publication number: 20040130410
    Abstract: A transmission band filter (110) having a series of elements (111, 113, 115) each composed of a film bulk acoustic resonator and grounded shunt elements (112, 114) each composed of a film bulk acoustic resonator is connected between a transmission port (102) and an antenna port (106). A reception band filter (130) having a series of elements (131, 133, 135) each composed of a film bulk acoustic resonator and grounded shunt elements (132, 134, 136) each composed of a film bulk acoustic resonator is connected between a reception port (104) and the antenna port (106). A film bulk acoustic resonator (150) for adjustment is connected between the antenna port (106) and the ground. The resonance frequency of the adjusting film bulk acoustic resonator (150) lies between the upper limit frequency of the transmission frequency pass band of the transmission band filter (110) and the lower limit frequency of the reception frequency pass band of the reception band filter (130).
    Type: Application
    Filed: October 28, 2003
    Publication date: July 8, 2004
    Inventors: Kosuke Nishimura, Keigo Nagao, Chisen Hashimoto, Eiji Masui, Hirofumi Kimura
  • Patent number: 6692769
    Abstract: The present invention discloses sustained release particles having a mean particle size of 300 &mgr;m, or less, comprising a drug-containing core substance coated with a mixed coating of a hydrophobic organic compound-water-insoluble polymer, which prevents sticking during compression molding when producing oral sustained release tablets, a preparation method of those sustained release particles, and a preparation method of tablets using those sustained release particles.
    Type: Grant
    Filed: April 26, 2001
    Date of Patent: February 17, 2004
    Assignee: Tanabe Seiyaku Co., Ltd.
    Inventors: Takashi Ishibashi, Keigo Nagao, Kengo Ikegami, Hiroyuki Yoshino, Masakazu Mizobe
  • Patent number: 6692768
    Abstract: The present invention discloses an efficient preparation method of spherical fine particles containing a drug for an easily-swallowed, controlled-release preparation comprising the production of drug-containing spherical fine particles (mean particle size: 60-200 &mgr;m) by adding a binder solution to a mixture containing an excipient powder having the property of retaining solvent (and preferably having a mean length of the long axis of 40 &mgr;m or less) and a drug powder (preferably having a mean length of the long axis of 50 &mgr;m or less), followed by high-speed mixing granulation.
    Type: Grant
    Filed: April 26, 2001
    Date of Patent: February 17, 2004
    Assignee: Tanabe Seiyaku Co., Ltd.
    Inventors: Takashi Ishibashi, Keigo Nagao, Kengo Ikegami, Hiroyuki Yoshino, Masakazu Mizobe
  • Publication number: 20030012815
    Abstract: The present invention is to provide a sustained release preparation comprising a drug-containing core substance and a multilayered coating layer covering the core substance, wherein all adjacent layers in the multilayered coating layer contain mutually different hydrophobic organic compound-water-soluble polymer mixtures; and, a method of producing a sustained release preparation, having a multilayered coating layer in which adjacent layers contain different hydrophobic organic compound-water-soluble polymer mixtures, which comprises spray-coating a solution containing a hydrophobic organic compound-water-soluble polymer mixture onto a drug-containing core substance, continuing to spray-coat a solution containing a different hydrophobic organic compound-water-soluble polymer mixture onto the resulting coating layer, and repeating this step.
    Type: Application
    Filed: July 25, 2002
    Publication date: January 16, 2003
    Inventors: Takashi Ishibashi, Kengo Ikegami, Keigo Nagao, Hiroyuki Yoshino, Masakazu Mizobe
  • Publication number: 20020190814
    Abstract: A pit (52) is formed in a substrate comprising a silicon wafer (51) on a surface of which a silicon oxide thin layer (53) is formed. A sandwich structure (60) comprising a piezoelectric layer (62) and lower and upper electrodes (61, 63) joined to both surfaces of the piezoelectric layer is disposed so as to stride over the pit (52). The upper surface of the lower electrode (61) and the lower surface of the piezoelectric layer (62) joined to the upper surface of the lower electrode are treated so that the RMS variation of the height thereof is equal to 25 nm or less. The thickness of the lower electrode (61) is set to 150 nm or less. According to such a structure, there is provided a high-performance thin film bulk acoustic resonator which are excellent in electromechanical coupling coefficient and acoustic quality factor.
    Type: Application
    Filed: May 9, 2002
    Publication date: December 19, 2002
    Inventors: Tetsuo Yamada, Keigo Nagao, Chisen Hashimoto