Patents by Inventor Takatomo Sasaki

Takatomo Sasaki 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: 9017479
    Abstract: The apparatus has a crucible for storing a solution; an inner container for storing a crucible; a heating container for storing the inner container, the heating container including heating elements, a container body provided with the heating elements and a lid combined with the container body; and a pressure vessel for storing the heating container and for charging an atmosphere comprising at least nitrogen gas. The lid also has a fitting surface to the container body that is inclined to a horizontal plane.
    Type: Grant
    Filed: July 29, 2008
    Date of Patent: April 28, 2015
    Assignees: NGK Insulators, Ltd., Osaka University, Toyoda Gosei Co., Ltd.
    Inventors: Makoto Iwai, Takanao Shimodaira, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura, Shiro Yamasaki
  • Patent number: 8999059
    Abstract: A growth apparatus is used having a plurality of crucibles each for containing the solution, a heating element for heating the crucible, and a pressure vessel for containing at least the crucibles and the heating element and for filling an atmosphere comprising at least nitrogen gas. One seed crystal is put in each of the crucibles to grow the nitride single crystal on the seed crystal.
    Type: Grant
    Filed: September 22, 2008
    Date of Patent: April 7, 2015
    Assignees: NGK Insulators, Ltd., Osaka University
    Inventors: Katsuhiro Imai, Makoto Iwai, Takanao Shimodaira, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura
  • Publication number: 20140063688
    Abstract: A capacitor module includes a first film capacitor, a second film capacitor, and a bus bar. The first film capacitor has electrodes at both ends thereof. The second film capacitor has electrodes at both ends thereof A lateral face of the second film capacitor is provided adjacent to a lateral face of the first film capacitor. The bus bar electrically connects the first film capacitor and the second film capacitor to an external device. The bus bar is connected to the electrodes on one end side of the first film capacitor and the second film capacitor. The bus bar is extended to the other end side through a gap between the first film capacitor and the second film capacitor.
    Type: Application
    Filed: September 3, 2013
    Publication date: March 6, 2014
    Applicants: KOJIMA PRESS INDUSTRY CO., LTD., TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventor: Takatomo SASAKI
  • Patent number: 8657955
    Abstract: It is provided a melt composition for growing a gallium nitride single crystal by flux method. The melt composition contains gallium, sodium and barium, and a content of barium is 0.05 to 0.3 mol % with respect to 100 mol % of sodium.
    Type: Grant
    Filed: August 3, 2009
    Date of Patent: February 25, 2014
    Assignees: NGK Insulators, Ltd, Osaka University, Toyoda Gosei Co., Ltd.
    Inventors: Makoto Iwai, Takanao Shimodaira, Yoshihiko Yamamura, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura, Shiro Yamasaki
  • Patent number: 8574361
    Abstract: A method for producing a high-quality group-III element nitride crystal at a high crystal growth rate, and a group-III element nitride crystal are provided. The method includes the steps of placing a group-III element, an alkali metal, and a seed crystal of group-III element nitride in a crystal growth vessel, pressurizing and heating the crystal growth vessel in an atmosphere of nitrogen-containing gas, and causing the group-III element and nitrogen to react with each other in a melt of the group-III element, the alkali metal and the nitrogen so that a group-III element nitride crystal is grown using the seed crystal as a nucleus. A hydrocarbon having a boiling point higher than the melting point of the alkali metal is added before the pressurization and heating of the crystal growth vessel.
    Type: Grant
    Filed: March 5, 2008
    Date of Patent: November 5, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Osamu Yamada, Hisashi Minemoto, Kouichi Hiranaka, Takeshi Hatakeyama, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura, Yasuo Kitaoka
  • Patent number: 8506705
    Abstract: A nitride single crystal is produced on a seed crystal substrate 5 in a melt containing a flux and a raw material of the single crystal in a growing vessel 1. The melt 2 in the growing vessel 1 has temperature gradient in a horizontal direction. In growing a nitride single crystal by flux method, adhesion of inferior crystals onto the single crystal is prevented and the film thickness of the single crystal is made constant.
    Type: Grant
    Filed: September 9, 2009
    Date of Patent: August 13, 2013
    Assignee: NGK Insulators, Ltd.
    Inventors: Mikiya Ichimura, Katsuhiro Imai, Makoto Iwai, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura, Yasuo Kitaoka
  • Patent number: 8486190
    Abstract: A raw material mixture containing an easily oxidizable material is weighed. The raw material mixture is melted and then solidified within a reaction vessel 1 set in a non-oxidizing atmosphere to thereby produce a solidified matter 19. The reaction vessel 1 and the solidified matter 19 are heated in a non-oxidizing atmosphere within a crystal growth apparatus to melt the solidified matter to thereby produce a solution. A single crystal is grown from the solution.
    Type: Grant
    Filed: September 22, 2008
    Date of Patent: July 16, 2013
    Assignees: NGK Insulators, Ltd., Osaka University
    Inventors: Katsuhiro Imai, Makoto Iwai, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura
  • Patent number: 8361222
    Abstract: In the production of GaN through the flux method, deposition of miscellaneous crystals on the nitrogen-face of a GaN self-standing substrate and waste of raw materials are prevented. Four arrangements of crucibles and a GaN self-standing substrate are exemplified. In FIG. 1A, a nitrogen-face of a self-standing substrate comes into close contact with a sloped flat inner wall of a crucible. In FIG. 1B, a nitrogen-face of a self-standing substrate comes into close contact with a horizontally facing flat inner wall of a crucible, and the substrate is fixed by means of a jig. In FIG. 1C, a jig is provided on a flat bottom of a crucible, and two GaN self-standing substrates are fixed by means of the jig so that the nitrogen-faces of the substrates come into close contact with each other. In FIG. 1D, a jig is provided on a flat bottom of a crucible, and a GaN self-standing substrate is fixed on the jig so that the nitrogen-face of the substrate is covered with the jig.
    Type: Grant
    Filed: April 23, 2008
    Date of Patent: January 29, 2013
    Assignees: Toyoda Gosei Co., Ltd., NGK Insulators, Ltd.
    Inventors: Shiro Yamazaki, Seiji Nagai, Takayuki Sato, Katsuhiro Imai, Makoto Iwai, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura
  • Patent number: 8287760
    Abstract: A light-emitting apparatus composed of a light source that emits primary light and a phosphor that absorbs the primary light and emits secondary light offers high brightness, low power consumption, and a long lifetime while minimizing adverse effects on the environment. The phosphor is formed of a III-V group semiconductor in the form of fine-particle crystals each having a volume of 2 800 nm3 or less. The light emitted from the fine-particle crystals depends on their volume, and therefore giving the fine-particle crystals a predetermined volume distribution makes it possible to adjust the wavelength range of the secondary light.
    Type: Grant
    Filed: February 22, 2010
    Date of Patent: October 16, 2012
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Masaya Ishida, Tatsuya Morioka, Daisuke Hanaoka, Mototaka Taneya, Shigeo Fujita, Yoichi Kawakami, Masafumi Harada, Takatomo Sasaki, Yusuke Mori
  • Patent number: 8231729
    Abstract: It is disclosed an apparatus for growing a nitride single crystal using a flux containing an easily oxidizable substance. The apparatus has a crucible for storing the flux; a pressure vessel for storing the crucible and charging an atmosphere containing at least nitrogen gas; furnace materials disposed within the pressure vessel and out of the crucible; heaters attached to the furnace material; and alkali-resistant and heat-resistant metallic layers covering the furnace material.
    Type: Grant
    Filed: August 15, 2008
    Date of Patent: July 31, 2012
    Assignees: NGK Insulators, Ltd., Osaka University, Toyoda Gosei Co., Ltd.
    Inventors: Makoto Iwai, Takanao Shimodaira, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura, Shiro Yamasaki
  • Patent number: 8227324
    Abstract: A GaN single crystal 20 is grown on a crystal growth surface of a seed crystal (GaN layer 13) through the flux method in a nitrogen (N2) atmosphere at 3.7 MPa and 870° C. employing a flux mixture including Ga, Na, and Li at about 870° C. Since the back surface of the template 10 is R-plane of the sapphire substrate 11, the template 10 is readily corroded or dissolved in the flux mixture from the back surface thereof. Therefore, the template 10 is gradually dissolved or corroded from the back surface thereof, resulting in separation from the semiconductor or dissolution in the flux. When the GaN single crystal 20 is grown to a sufficient thickness, for example, about 500 ?m or more, the temperature of the crucible is maintained at 850° C. to 880° C., whereby the entirety of the sapphire substrate 11 is dissolved in the flux mixture.
    Type: Grant
    Filed: December 10, 2007
    Date of Patent: July 24, 2012
    Assignees: Toyoda Gosei Co., Ltd., NGK Insulators, Ltd., Osaka University
    Inventors: Shiro Yamazaki, Makoto Iwai, Takanao Shimodaira, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura
  • Patent number: 8216365
    Abstract: Objects of the invention are to further enhance crystallinity and crystallinity uniformity of a semiconductor crystal produced through the flux method, and to effectively enhance the production yield of the semiconductor crystal. The c-axis of a seed crystal including a GaN single-crystal layer is aligned in a horizontal direction (y-axis direction), one a-axis of the seed crystal is aligned in the vertical direction, and one m-axis is aligned in the x-axis direction. Thus, three contact points at which a supporting tool contacts the seed crystal are present on m-plane. The supporting tool has two supporting members, which extend in the vertical direction. One supporting member has an end part, which is inclined at 30° with respect to the horizontal plane ?. The reasons for supporting a seed crystal at m-plane thereof are that m-plane exhibits a crystal growth rate, which is lower than that of a-plane, and that desired crystal growth on c-plane is not inhibited.
    Type: Grant
    Filed: February 29, 2008
    Date of Patent: July 10, 2012
    Assignee: Toyoda Gosei Co., Ltd.
    Inventors: Seiji Nagai, Shiro Yamazaki, Takayuki Sato, Katsuhiro Imai, Makoto Iwai, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura
  • Publication number: 20120168695
    Abstract: A method for producing a high-quality group-III element nitride crystal at a high crystal growth rate, and a group-III element nitride crystal are provided. The method includes the steps of placing a group-III element, an alkali metal, and a seed crystal of group-III element nitride in a crystal growth vessel, pressurizing and heating the crystal growth vessel in an atmosphere of nitrogen-containing gas, and causing the group-III element and nitrogen to react with each other in a melt of the group-III element, the alkali metal and the nitrogen so that a group-III element nitride crystal is grown using the seed crystal as a nucleus. A hydrocarbon having a boiling point higher than the melting point of the alkali metal is added before the pressurization and heating of the crystal growth vessel.
    Type: Application
    Filed: March 5, 2008
    Publication date: July 5, 2012
    Applicant: PANASONIC CORPORATION
    Inventors: Osamu YAMADA, Hisashi MINEMOTO, Kouichi HIRANAKA, Takeshi HATAKEYAMA, Takatomo SASAKI, Yusuke MORI, Fumio KAWAMURA, Yasuo KITAOKA
  • Patent number: 8187507
    Abstract: A method for producing a GaN crystal capable of achieving at least one of the prevention of nucleation and the growth of a high-quality non-polar surface is provided. The production method of the present invention is a method for producing a GaN crystal in a melt containing at least an alkali metal and gallium, including an adjustment step of adjusting the carbon content of the melt, and a reaction step of causing the gallium and nitrogen to react with each other. According to the production method of the present invention, nucleation can be prevented, and as shown in FIG. 4, a non-polar surface can be grown.
    Type: Grant
    Filed: November 14, 2007
    Date of Patent: May 29, 2012
    Assignee: Osaka University
    Inventors: Yusuke Mori, Takatomo Sasaki, Fumio Kawamura, Masashi Yoshimura, Minoru Kawahara, Yasuo Kitaoka, Masanori Morishita
  • Patent number: 8123856
    Abstract: In the flux method, a source nitrogen gas is sufficiently heated before feeding to an Na—Ga mixture. The apparatus of the invention is provided for producing a group III nitride based compound semiconductor. The apparatus includes a reactor which maintains a group III metal and a metal differing from the group III metal in a molten state, a heating apparatus for heating the reactor, an outer vessel for accommodating the reactor and the heating apparatus, and a feed pipe for feeding a gas containing at least nitrogen from the outside of the outer vessel into the reactor. The feed pipe has a zone for being heated together with the reactor by means of the heating apparatus, wherein the zone is heated inside the outer vessel and outside the reactor.
    Type: Grant
    Filed: April 5, 2007
    Date of Patent: February 28, 2012
    Assignees: Toyoda Gosei Co., Ltd., NGK Insulators, Ltd., Osaka University
    Inventors: Shiro Yamazaki, Makoto Iwai, Takanao Shimodaira, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura
  • Patent number: 8084281
    Abstract: The present invention provides a method for producing a semiconductor substrate, the method including reacting nitrogen (N) with gallium (Ga), aluminum (Al), or indium (In), which are group III elements, in a flux mixture containing a plurality of metal elements selected from among alkali metals and alkaline earth metals, to thereby grow a group III nitride based compound semiconductor crystal. The group III nitride based compound semiconductor crystal is grown while the flux mixture and the group III element are mixed under stirring. At least a portion of a base substrate on which the group III nitride based compound semiconductor crystal is grown is formed of a flux-soluble material, and the flux-soluble material is dissolved in the flux mixture, at a temperature near the growth temperature of the group III nitride based compound semiconductor crystal, during the course of growth of the semiconductor crystal.
    Type: Grant
    Filed: March 15, 2007
    Date of Patent: December 27, 2011
    Assignees: Toyoda Gosei Co., Ltd., NGK Insulators, Ltd., Osaka University
    Inventors: Naoki Shibata, Koji Hirata, Shiro Yamazaki, Katsuhiro Imai, Makoto Iwai, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura
  • Patent number: 8037739
    Abstract: A method for analyzing a sample in a liquid is provided, which is suitable for easily and reliably preventing a liquid for analysis from being evaporated. When the sample in the liquid is observed by using a scanning probe microscope (SPM), a sealing liquid (17) immiscible with a liquid for analysis (16) is filled around the liquid for analysis (16), in which a sample (13) and a probe (15) are immersed, so as to form a sealing state, in which the liquid for analysis (16) is isolated from an external gas. The SPM enables the probe (15) disposed on a front end of a cantilever (14) to approach a surface of the sample (13) immersed in the liquid, scans the surface of the sample, and detects an interaction between the sample (13) and the probe (15), thereby generating an image.
    Type: Grant
    Filed: August 22, 2008
    Date of Patent: October 18, 2011
    Assignee: Shimadzu Corporation
    Inventors: Masahiro Ota, Noriaki Oyabu, Hiroaki Adachi, Masayuki Abe, Seizo Morita, Yusuke Mori, Takatomo Sasaki
  • Patent number: 8038794
    Abstract: A method of manufacturing a group III-nitride crystal substrate including the steps of introducing an alkali-metal-element-containing substance, a group III-element-containing substance and a nitrogen-element-containing substance into a reactor, forming a melt containing at least the alkali metal element, the group III-element and the nitrogen element in the reactor, and growing group III-nitride crystal from the melt, and characterized by handling the alkali-metal-element-containing substance in a drying container in which moisture concentration is controlled to at most 1.0 ppm at least in the step of introducing the alkali-metal-element-containing substance into the reactor is provided. A group III-nitride crystal substrate attaining a small absorption coefficient and the method of manufacturing the same, as well as a group III-nitride semiconductor device can thus be provided.
    Type: Grant
    Filed: April 15, 2005
    Date of Patent: October 18, 2011
    Assignees: Sumitomo Electric Industries, Ltd.
    Inventors: Takatomo Sasaki, Yusuke Mori, Masashi Yoshimura, Fumio Kawamura, Seiji Nakahata, Ryu Hirota
  • Patent number: 8025728
    Abstract: A seed crystal is immersed in a melt containing a flux and a single crystal material in a growth vessel to produce a nitride single crystal on the seed crystal. A difference (TS-TB) of temperatures at a gas-liquid interface of the melt (TS) and at the lowermost part of the melt (TB) is set to 1° C. or larger and 8° C. or lower. Preferably, the substrate of seed crystal is vertically placed.
    Type: Grant
    Filed: September 22, 2008
    Date of Patent: September 27, 2011
    Assignees: NGK Insulators, Ltd., Osaka University
    Inventors: Mikiya Ichimura, Katsuhiro Imai, Chikashi Ihara, Takatomo Sasaki, Yusuke Mori, Fumio Kawamura
  • Patent number: 7959729
    Abstract: A production method is provided in which Group-III-element nitride single crystals that have a lower dislocation density and a uniform thickness and are transparent, high quality, large, and bulk crystals can be produced with a high yield. The method for producing Group-III-element nitride single crystals includes: heating a reaction vessel containing at least one metal element selected from the group consisting of an alkali metal and an alkaline-earth metal and at least one Group III element selected from the group consisting of gallium (Ga), aluminum (Al), and indium (In) to prepare a flux of the metal element; and feeding nitrogen-containing gas into the reaction vessel and thereby allowing the Group III element and nitrogen to react with each other in the flux to grow Group-III-element nitride single crystals, wherein the single crystals are grown, with the flux being stirred by rocking the reaction vessel, for instance.
    Type: Grant
    Filed: March 15, 2004
    Date of Patent: June 14, 2011
    Assignee: Osaka University
    Inventors: Takatomo Sasaki, Yusuke Mori, Masashi Yoshimura, Fumio Kawamura, Hidekazu Umeda