Patents by Inventor Masato Aoki

Masato Aoki 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: 20130256687
    Abstract: A group III nitride compound semiconductor light emitting device that inhibits occurrence of dislocation in a strain relaxation layer in forming a group III nitride compound semiconductor layer on a thin GaN substrate, and a method for producing the same are provided. A light emitting device 100 comprises a support substrate 10, a GaN substrate 20, an n-type contact layer 30, a strain relaxation layer 40 (n-type InGaN layer), a light emitting layer 50, a p-type clad layer 60, and a p-type contact layer 70. The GaN substrate 20 has a thickness in a range of from 10 nm to 10 ?m. The strain relaxation layer 40 (n-type InGaN layer) has an In composition ratio X in a range of from larger than 0 to 3%.
    Type: Application
    Filed: March 4, 2013
    Publication date: October 3, 2013
    Applicant: TOYODA GOSEI CO., LTD.
    Inventors: Yoshiki SAITO, Yasuhisa USHIDA, Masato AOKI
  • Patent number: 8547052
    Abstract: A driving control apparatus includes an inverter circuit, a motor driving circuit and a motor control unit. In performing overlap energization, at a start time of an overlap time period, a pulse width of a first PWM signal at an energization side is widened to increase a number of pulses of a second PWM signal accordingly, and a first PWM signal at an energization side corresponding to a constant voltage side is also widened.
    Type: Grant
    Filed: March 6, 2012
    Date of Patent: October 1, 2013
    Assignee: Minebea Co., Ltd.
    Inventor: Masato Aoki
  • Publication number: 20130240945
    Abstract: A method for producing a group III nitride semiconductor light-emitting device, by which a non-light-emitting region is easily formed, is disclosed. Mg is activated to convert a p-type layer into p-type, and a p-electrode is then formed on the p-type layer. An Ag paste is applied to a region on the p-electrode and overlapping an n-electrode formed in a subsequent step. Heat treatment is conducted to solidify the Ag paste, thereby forming an Ag paste solidified body. By this, a region overlapping the Ag paste solidified body in a planar view, of the p-type layer converts into a region having high resistance, and a high resistance region is formed. As a result, a region overlapping the high resistance region in a planar view, of a light-emitting layer becomes a non-light-emitting region.
    Type: Application
    Filed: February 19, 2013
    Publication date: September 19, 2013
    Applicant: TOYODA GOSEI CO., LTD.
    Inventors: Masato AOKI, Koichi GOSHONOO, Satoshi WADA
  • Publication number: 20130069564
    Abstract: There is provided a power controller including a drive circuit connected to a DC power supply to apply a first voltage to the drive circuit and configured to supply power to an external load, a current detection circuit configured to detect a current flowing in the drive circuit by converting the current into a second voltage corresponding to the current, and a current-voltage control unit configured to generate a reference voltage corresponding to a limit value of the current flowing in the drive circuit when the first voltage is applied to the drive circuit, and configured to control the drive circuit to operate in a desired current according to the first voltage, based on a comparison result of the reference voltage and the second voltage.
    Type: Application
    Filed: September 10, 2012
    Publication date: March 21, 2013
    Applicant: MINEBEA CO., LTD.
    Inventors: Hiroyuki KAIDU, Masato AOKI
  • Publication number: 20120315626
    Abstract: The sterilizing effect of particle irradiation on microorganisms for the sterilizing treatment thereof can be evaluated. The evaluation can be done by supplying microorganisms in the space inside a container (8), allowing particles (7) for the sterilizing treatment of microorganisms to irradiate the microorganisms, sampling the microorganisms by a sampling means (6) after the irradiation of the particles (7) and measuring the sampled microorganisms. The microorganisms as the subject for the sterilizing treatment can be a combination of one or more members selected from the group consisting of bacteria, mycete, viruses and allergens. As the particles, for example, positive ions, negative ions, and gases of positive ions and negative ions in mixture, charged particles such as a rays and ? rays, various plasma gas particles, particles such as ozone and radical particles, and particles of chemical agent can be used.
    Type: Application
    Filed: June 13, 2012
    Publication date: December 13, 2012
    Inventors: Kazuo NISHIKAWA, Hisaharu YAGI, Yoshihiro SHIMIZU, Tetsuyuki OHTANI, Hideo NOJIMA, Masato AOKI, Miyuki Aoki
  • Publication number: 20120293100
    Abstract: A driving control apparatus includes an inverter circuit, a motor driving circuit and a motor control unit. In performing overlap energization, at a start time of an overlap time period, a pulse width of a first PWM signal at an energization side is widened to increase a number of pulses of a second PWM signal accordingly, and a first PWM signal at an energization side corresponding to a constant voltage side is also widened.
    Type: Application
    Filed: March 6, 2012
    Publication date: November 22, 2012
    Applicant: MINEBEA CO., LTD.
    Inventor: Masato AOKI
  • Publication number: 20110012235
    Abstract: A method of growing a group III nitride crystal grows a group III nitride crystal from a solution in which an alkaline metal, a group III metal and nitrogen are dissolved, and includes, in the solution, a material which increases solubility of the nitrogen into the solution.
    Type: Application
    Filed: September 27, 2010
    Publication date: January 20, 2011
    Inventors: Hirokazu Iwata, Seiji Sarayama, Hisanori Yamane, Masahiko Shimada, Masato Aoki
  • Patent number: 7828896
    Abstract: A method of growing a group III nitride crystal grows a group III nitride crystal from a solution in which an alkaline metal, a group III metal and nitrogen are dissolved, and includes, in the solution, a material which increases solubility of the nitrogen into the solution.
    Type: Grant
    Filed: July 20, 2007
    Date of Patent: November 9, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Hirokazu Iwata, Seiji Sarayama, Hisanori Yamane, Masahiko Shimada, Masato Aoki
  • Patent number: 7824929
    Abstract: An object of the present invention is to remove micro-scratches on a surface of a GaN substrate cut from a GaN ingot. The invention is directed to establish a method for surface treatment of a GaN substrate, including heating the surface in an atmosphere containing trimethylgallium, ammonia, and hydrogen. It is preferable that the trimethylgallium feeding rate is 150 ?mol/min or higher, the ratio of trimethylgallium feeding rate to ammonia feeding rate (V/III ratio) is 1,200 to 4,000, and the heating temperature is 1,000° C. to 1,250° C. In addition, the temperature of the surface treatment is set to be higher than that of the following GaN growth, and the feed rate of trimethylgallium is lower than that of the growth procedure. RMS of roughness on the substrate was equal to or less than 1.3 nm, and the substrate whose step condition is excellent can be obtained.
    Type: Grant
    Filed: October 21, 2008
    Date of Patent: November 2, 2010
    Assignee: Toyoda Gosei Co., Ltd.
    Inventors: Masato Aoki, Miki Moriyama
  • Patent number: 7629619
    Abstract: A Group III nitride-based compound semiconductor light-emitting device having a quantum well structure, includes a well layer, a first layer formed on one surface of the well layer, a second layer formed on the other surface of the well layer, a first region provided in the vicinity of the interface between the first layer and the well layer, and a second region provided in the vicinity of the interface between the second layer and the well layer. A composition of the first and second regions gradually changes such that the lattice constants of the first and second layers approach the lattice constant of the well layer as a position approaches said well layer.
    Type: Grant
    Filed: January 27, 2006
    Date of Patent: December 8, 2009
    Assignee: Toyota Gosei Co., Ltd.
    Inventors: Tetsuya Taki, Mitsuhisa Narukawa, Masato Aoki, Koji Okuno, Yusuke Toyoda, Kazuki Nishijima, Shuhei Yamada
  • Publication number: 20090104757
    Abstract: An object of the present invention is to remove micro-scratches on a surface of a GaN substrate cut from a GaN ingot. The invention is directed to establish a method for surface treatment of a GaN substrate, including heating the surface in an atmosphere containing trimethylgallium, ammonia, and hydrogen. It is preferable that the trimethylgallium feeding rate is 150 ?mol/min or higher, the ratio of trimethylgallium feeding rate to ammonia feeding rate (V/III ratio) is 1,200 to 4,000, and the heating temperature is 1,000° C. to 1,250° C. In addition, the temperature of the surface treatment is set to be higher than that of the following GaN growth, and the feed rate of trimethylgallium is lower than that of the growth procedure. RMS of roughness on the substrate was equal to or less than 1.3 nm, and the substrate whose step condition is excellent can be obtained.
    Type: Application
    Filed: October 21, 2008
    Publication date: April 23, 2009
    Applicant: TOYODA GOSEI CO., LTD.
    Inventors: Masato Aoki, Miki Moriyama
  • Publication number: 20080282969
    Abstract: A crystal growth method, comprising the steps of: a) bringing a nitrogen material into a reaction vessel in which a mixed molten liquid comprising an alkaline metal and a group-III metal; and b) growing a crystal of a group-III nitride using the mixed molten liquid and the nitrogen material brought in by the step a) in the reaction vessel, wherein a provision is made such as to prevent a vapor of the alkaline metal from dispersing out of the reaction vessel.
    Type: Application
    Filed: June 13, 2008
    Publication date: November 20, 2008
    Applicant: Ricoh Company, Ltd,
    Inventors: Seiji Sarayama, Masahiko Shimada, Hisanori Yamane, Masato Aoki
  • Publication number: 20070266928
    Abstract: A method of growing a group III nitride crystal grows a group III nitride crystal from a solution in which an alkaline metal, a group III metal and nitrogen are dissolved, and includes, in the solution, a material which increases solubility of the nitrogen into the solution.
    Type: Application
    Filed: July 20, 2007
    Publication date: November 22, 2007
    Inventors: Hirokazu Iwata, Seiji Sarayama, Hisanori Yamane, Masahiko Shimada, Masato Aoki
  • Patent number: 7261775
    Abstract: A method of growing a group III nitride crystal grows a group III nitride crystal from a solution in which an alkaline metal, a group III metal and nitrogen are dissolved, and includes, in the solution, a material which increases solubility of the nitrogen into the solution.
    Type: Grant
    Filed: January 28, 2004
    Date of Patent: August 28, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Hirokazu Iwata, Seiji Sarayama, Hisanori Yamane, Masahiko Shimada, Masato Aoki
  • Publication number: 20060247552
    Abstract: The bone marrow harvesting set according to the invention includes: a centrifuge container used for harvesting bone marrow; a cap with a collection inlet; and a collection tube with connectors attached to both ends thereof, the set being constructed in such a manner as to put the cap on the centrifuge container, fit one of the connectors into the collection inlet of the cap, and fit the other connector into the mantle of the bone marrow harvesting needle so as to collect bone marrow. The bone marrow harvesting needle includes: a tubular mantle and an inner needle with its tip allowed to project from the mantle, the inner needle having a drilling edge formed at its tip and the mantle having a cutting edge formed at its tip.
    Type: Application
    Filed: June 27, 2006
    Publication date: November 2, 2006
    Inventors: Susumu Ikehara, Shuji Nakamura, Masato Aoki, Masaaki Numazawa, Masakazu Adachi
  • Publication number: 20060169990
    Abstract: The invention relates to a Group III nitride-based compound semiconductor light-emitting device having a well layer, a first layer formed on one surface of the well layer, a second layer formed on the other surface of the well layer, a first region provided in the vicinity of the interface between the first layer and the well layer, and a second region provided in the vicinity of the interface between the second layer and the well layer, wherein the first and second regions are formed such that the lattice constants of the first and second layers approach the lattice constant of the well layer.
    Type: Application
    Filed: January 27, 2006
    Publication date: August 3, 2006
    Applicant: Toyoda Gosei Co., Ltd.
    Inventors: Tetsuya Taki, Mitsuhisa Narukawa, Masato Aoki, Koji Okuno, Yusuke Toyoda, Kazuki Nishijima, Shuhei Yamada
  • Patent number: 6949140
    Abstract: A group-III nitride crystal growth method, comprising the steps of: a) preparing a mixed molten liquid of an alkaline metal and a material at least comprising a group-III metal; b) growing a group-III nitride crystal of the group-III metal and nitrogen from the mixed molten liquid and a material at least comprising nitrogen; and c) setting a predetermined crystal growth condition according to a zone defined by a pressure and a temperature in said step b).
    Type: Grant
    Filed: December 3, 2002
    Date of Patent: September 27, 2005
    Assignee: Ricoh Company, Ltd.
    Inventors: Seiji Sarayama, Hirokazu Iwata, Masahiko Shimada, Hisanori Yamane, Masato Aoki
  • Publication number: 20050026318
    Abstract: A crystal growth method, comprising the steps of: a) bringing a nitrogen material into a reaction vessel in which a mixed molten liquid comprising an alkaline metal and a group-III metal; and b) growing a crystal of a group-III nitride using the mixed molten liquid and the nitrogen material brought in by the step a) in the reaction vessel, wherein a provision is made such as to prevent a vapor of the alkaline metal from dispersing out of the reaction vessel.
    Type: Application
    Filed: June 28, 2004
    Publication date: February 3, 2005
    Inventors: Seiji Sarayama, Masahiko Shimada, Hisanori Yamane, Masato Aoki
  • Publication number: 20040226503
    Abstract: A method of growing a group III nitride crystal grows a group III nitride crystal from a solution in which an alkaline metal, a group III metal and nitrogen are dissolved, and includes, in the solution, a material which increases solubility of the nitrogen into the solution.
    Type: Application
    Filed: January 28, 2004
    Publication date: November 18, 2004
    Inventors: Hirokazu Iwata, Seiji Sarayama, Hisanori Yamane, Masahiko Shimada, Masato Aoki
  • Publication number: 20040215102
    Abstract: The bone marrow harvesting set according to the invention includes: a centrifuge container used for harvesting bone marrow; a cap with a collection inlet; and a collection tube with connectors attached to both ends thereof, the set being constructed in such a manner as to put the cap on the centrifuge container, fit one of the connectors into the collection inlet of the cap, and fit the other connector into the mantle of the bone marrow harvesting needle so as to collect bone marrow. The bone marrow harvesting needle includes: a tubular mantle and an inner needle with its tip allowed to project from the mantle, the inner needle having a drilling edge formed at its tip and the mantle having a cutting edge formed at its tip.
    Type: Application
    Filed: January 29, 2004
    Publication date: October 28, 2004
    Inventors: Susumu Ikehara, Shuji Nakamura, Masato Aoki, Masaaki Numazawa, Masakazu Adachi