Patents by Inventor Kazuo Nakajima

Kazuo Nakajima 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: 20230304185
    Abstract: A method for producing Si ingot single crystal by NOC growth method including a Si ingot single crystal growing step and a continuous growing step is provided. The growing step includes providing a low temperature region in the Si melt where the Si ingot single crystal is grown along the surface of the Si melt or toward the inside of the Si melt, and the Si ingot single crystal has distribution of a vacancy concentration and an interstitial concentration in which respectively a vacancy concentration and an interstitial concentration vary with a distance from the growth interface; and adjusting a temperature gradient and a growth rate in the Si melt, so that along with the increasing of the distance from the growth interface, the vacancy concentration and the interstitial concentration in the Si ingot single crystal respectively decrease come near to each other.
    Type: Application
    Filed: May 30, 2023
    Publication date: September 28, 2023
    Applicant: GlobalWafers Co., Ltd.
    Inventors: Kazuo Nakajima, Masami Nakanishi, Yu Sheng Su, Wen-Ching Hsu
  • Publication number: 20230295833
    Abstract: A method for producing Si ingot single crystal by NOC growth method including a Si ingot single crystal growing step and a continuous growing step is provided. The growing step includes providing a low temperature region in the Si melt where the Si ingot single crystal is grown along the surface of the Si melt or toward the inside of the Si melt, and the Si ingot single crystal has distribution of a vacancy concentration and an interstitial concentration in which respectively a vacancy concentration and an interstitial concentration vary with a distance from the growth interface; and adjusting a temperature gradient and a growth rate in the Si melt, so that along with the increasing of the distance from the growth interface, the vacancy concentration and the interstitial concentration in the Si ingot single crystal respectively decrease come near to each other.
    Type: Application
    Filed: May 30, 2023
    Publication date: September 21, 2023
    Applicant: GlobalWafers Co., Ltd.
    Inventors: Kazuo Nakajima, Masami Nakanishi, Yu Sheng Su, Wen-Ching Hsu
  • Publication number: 20230160095
    Abstract: A method for producing Si ingot single crystal including a Si ingot single crystal growing step, a temperature gradient controlling step and a continuous growing step is provided. In the growing step, the Si ingot single crystal is grown in silicon melt in crucible, and the growing step includes providing a low-temperature region in the Si melt and providing a silicon seed to contact the melt surface of the silicon melt to start crystal growth, and silicon single crystal grows along the melt surface of the silicon melt and toward the inside of the silicon melt. In the temperature gradient controlling step, the under-surface temperature gradient of the silicon single crystal is G1, the above-surface temperature gradient of the silicon single crystal is G2, G1 and G2 satisfy: G2/G1<6. The step of controlling the temperature gradient of silicon single crystal is repeated to obtain the Si ingot single crystal.
    Type: Application
    Filed: October 12, 2022
    Publication date: May 25, 2023
    Applicant: GlobalWafers Co., Ltd.
    Inventors: Kazuo Nakajima, Masami Nakanishi, Yu Sheng Su, Wen-Ching Hsu
  • Publication number: 20210363656
    Abstract: A method for producing Si ingot single crystal by NOC growth method including a Si ingot single crystal growing step and a continuous growing step is provided. The growing step includes providing a low temperature region in the Si melt where the Si ingot single crystal is grown along the surface of the Si melt or toward the inside of the Si melt, and the Si ingot single crystal has distribution of a vacancy concentration and an interstitial concentration in which respectively a vacancy concentration and an interstitial concentration vary with a distance from the growth interface; and adjusting a temperature gradient and a growth rate in the Si melt, so that along with the increasing of the distance from the growth interface, the vacancy concentration and the interstitial concentration in the Si ingot single crystal respectively decrease come near to each other.
    Type: Application
    Filed: May 19, 2021
    Publication date: November 25, 2021
    Applicant: GlobalWafers Co., Ltd.
    Inventors: Kazuo Nakajima, Masami Nakanishi, Yu Sheng Su, Wen-Ching Hsu
  • Patent number: 8991641
    Abstract: A toroidal pressure vessel having extremely high pressure resistance has laminated latitudinal reinforcing fiber layers to improve a strength in a latitudinal direction of the pressure vessel. Moreover, putting reinforcing fibers constituting those laminated latitudinal reinforcing fiber layers in continuity enables further improvement of strength in the latitudinal direction of the pressure vessel, for example compared with a case where the reinforcing fibers are divided for each layer.
    Type: Grant
    Filed: April 15, 2011
    Date of Patent: March 31, 2015
    Assignees: Mitsubishi Heavy Industries, Ltd., Shikibo Ltd.
    Inventors: Tetsuya Ozawa, Nozomu Kawasetsu, Kentaro Shindo, Mitsuru Kondo, Akira Fukushima, Masayasu Ishibashi, Takeshi Tanamura, Kazuo Nakajima, Hiroshi Sakai, Tetsuro Hirokawa
  • Patent number: 8824631
    Abstract: Provided is a technique for X-ray reflection, such as an X-ray reflecting mirror, capable of achieving a high degree of smoothness of a reflecting surface, high focusing (reflecting) performance, stability in a curved surface shape, and a reduction in overall weight. A silicon plate (silicon wafer) is subjected to thermal plastic deformation to form an X-ray reflecting mirror having a reflecting surface with a stable curved surface shape. The silicon wafer can be deformed to any shape by applying a pressure thereto in a hydrogen atmosphere at a high temperature of about 1300° C. The silicon plate may be simultaneously subjected to hydrogen annealing to further reduce roughness of a silicon surface to thereby provide enhanced reflectance.
    Type: Grant
    Filed: January 18, 2011
    Date of Patent: September 2, 2014
    Assignees: Japan Aerospace Exploration Agency, Tokyo Manufacturing University
    Inventors: Kazuhisa Mitsuda, Manabu Ishida, Yuichiro Ezoe, Kazuo Nakajima
  • Patent number: 8404043
    Abstract: A high-quality polycrystalline bulk semiconductor having a large crystal grain size is produced by the casting method in which growth is regulated so as to proceed in the same plane direction, i.e., the {110}; plane or {112} plane is disclosed. The process, which is for producing a polycrystalline bulk semiconductor, comprises: a step in which a melt of a semiconductor selected among Si, Ge, and SiGe is held in a crucible; a step in which a bottom part of the crucible is cooled to give a temperature gradient and that part of the melt which is located directly on the crucible bottom is rapidly cooled in the beginning of growth to supercool the melt around the crucible bottom; a step in which the crucible is cooled to grow nuclei on the crucible bottom due to the supercooled state of the melt around the crucible bottom and thereby grow dendritic crystals along the crucible bottom; and a step in which a polycrystalline bulk of the semiconductor is then grown on the upper side of the dendritic crystals.
    Type: Grant
    Filed: May 30, 2008
    Date of Patent: March 26, 2013
    Assignee: Tohoku University
    Inventors: Kozo Fujiwara, Kazuo Nakajima
  • Patent number: 8406379
    Abstract: In one embodiment of the present invention, a curvature distribution crystal lens of the present invention is obtained via press-molding. In the case of a Ge single crystal plate, a temperature for the press-molding is in a range 1° C. to 120° C. lower than a melting point. In the case of a Si single crystal plate, a temperature for the press-molding is in a range 1° C. to 200° C. lower than a melting point. The curvature distribution crystal lens has a crystal lattice plane forming a 1D cylindrically curved surface or a 1D logarithmically curved surface whose valley is in a direction perpendicular to a direction having a maximum curvature, the direction having the maximum curvature being within 30° from a [001] or [1-10] direction in a (110) plane. As a result, it is possible to make an integrated reflection intensity uniform and to make a half-value width uniform in a wide range.
    Type: Grant
    Filed: August 28, 2008
    Date of Patent: March 26, 2013
    Assignees: Kyoto University, Tohoku University
    Inventors: Hiroshi Okuda, Kazuo Nakajima, Kozo Fujiwara
  • Patent number: 8187563
    Abstract: A method is provided for producing a Si bulk polycrystal ingot with high quality and high homogeneity, which has no significant crystal defects and is free from diffused impurities with a high yield. An upper face of a Si melt is locally cooled by bringing coolant close to a surface of the Si melt from an upper part of a crucible in the crucible containing the Si melt or by inserting the coolant into the Si melt. A dendrite crystal is formed in the vicinity of the surface of the Si melt. Cooling is performed thereafter while maintaining a proper temperature distribution, and a Si bulk crystal is grown from an upper part toward a lower part using a lower face of the dendrite crystal as a fresh growth face.
    Type: Grant
    Filed: July 31, 2008
    Date of Patent: May 29, 2012
    Assignees: Tohoku Technoarch Co., Ltd., Daiichi Kiden Co., Ltd.
    Inventors: Noritaka Usami, Kazuo Nakajima, Isao Takahashi
  • Publication number: 20120024866
    Abstract: Provided is a toroidal pressure vessel having extremely high pressure resistance. Laminating latitudinal reinforcing fiber layers (32) enables to improve a strength in a latitudinal direction of a pressure vessel (1). Moreover, putting reinforcing fibers (32a) constituting those laminated latitudinal reinforcing fiber layers (32) in continuity enables to further improve the strength in the latitudinal direction of the pressure vessel (1), for example compared with a case where the reinforcing fibers are divided for each layer.
    Type: Application
    Filed: April 15, 2011
    Publication date: February 2, 2012
    Inventors: Tetsuya Ozawa, Nozomu Kawasetsu, Kentaro Shindo, Mitsuru Kondo, Akira Fukushima, Masayasu Ishibashi, Takeshi Tanamura, Kazuo Nakajima, Hiroshi Sakai, Tetsuro Hirokawa
  • Patent number: 8017862
    Abstract: In growing a single-crystal silicon by the present invention in a Czochralski method, after a surface of a silicon melt is brought into contact with a seed crystal in a crucible, the silicon melt being added with germanium, the single-crystal silicon is pulled while rotated, and the solar-cell single-crystal silicon substrate is sliced from the single-crystal silicon containing germanium, whereby a germanium content of solar-cell single-crystal silicon substrate is set in the range of not less than 0.03 mole % to less than 1.0 mole % when resistivity ranges from 1.4 to 1.9 ?cm. Therefore, conversion efficiency is enhanced when compared with conventional single-crystal silicon substrates. Accordingly, solar cell power generation costs decreases, so that the single-crystal silicon of the present invention can widely be utilized as the substrate for the solar cell in which the high conversion efficiency is increasingly demanded.
    Type: Grant
    Filed: October 20, 2006
    Date of Patent: September 13, 2011
    Assignee: Sumco Solar Corporation
    Inventors: Michio Kida, Wugen Pan, Kyojiro Kaneko, Kazuo Nakajima, Noritaka Usami, Kozo Fujiwara
  • Publication number: 20110110499
    Abstract: Provided is a technique for X-ray reflection, such as an X-ray reflecting mirror, capable of achieving a high degree of smoothness of a reflecting surface, high focusing (reflecting) performance, stability in a curved surface shape, and a reduction in overall weight. A silicon plate (silicon wafer) is subjected to thermal plastic deformation to form an X-ray reflecting mirror having a reflecting surface with a stable curved surface shape. The silicon wafer can be deformed to any shape by applying a pressure thereto in a hydrogen atmosphere at a high temperature of about 1300° C. The silicon plate may be simultaneously subjected to hydrogen annealing to further reduce roughness of a silicon surface to thereby provide enhanced reflectance.
    Type: Application
    Filed: January 18, 2011
    Publication date: May 12, 2011
    Inventors: Kazuhisa MITSUDA, Manabu ISHIDA, Yuichiro EZOE, Kazuo NAKAJIMA
  • Publication number: 20100208868
    Abstract: In one embodiment of the present invention, a curvature distribution crystal lens of the present invention is obtained via press-molding. In the case of a Ge single crystal plate, a temperature for the press-molding is in a range 1° C. to 120° C. lower than a melting point. In the case of a Si single crystal plate, a temperature for the press-molding is in a range 1° C. to 200° C. lower than a melting point. The curvature distribution crystal lens has a crystal lattice plane forming a 1D cylindrically curved surface or a 1D logarithmically curved surface whose valley is in a direction perpendicular to a direction having a maximum curvature, the direction having the maximum curvature being within 30° from a [001] or [1-10] direction in a (110) plane. As a result, it is possible to make an integrated reflection intensity uniform and to make a half-value width uniform in a wide range.
    Type: Application
    Filed: August 28, 2008
    Publication date: August 19, 2010
    Inventors: Hiroshi Okuda, Kazuo Nakajima, Kozo Fujiwara
  • Publication number: 20100202955
    Abstract: A method is provided for producing a Si bulk polycrystal ingot with high quality and high homogeneity, which has no significant crystal defects and is free from diffused impurities with a high yield. An upper face of a Si melt is locally cooled by bringing coolant close to a surface of the Si melt from an upper part of a crucible in the crucible containing the Si melt or by inserting the coolant into the Si melt. A dendrite crystal is formed in the vicinity of the surface of the Si melt. Cooling is performed thereafter while maintaining a proper temperature distribution, and a Si bulk crystal is grown from an upper part toward a lower part using a lower face of the dendrite crystal as a fresh growth face.
    Type: Application
    Filed: July 31, 2008
    Publication date: August 12, 2010
    Applicants: National Univeristy Corporation Tohoku Univeristy, ASA Co.LTd
    Inventors: Noritaka Usami, Kazuo Nakajima, Isao Takahashi
  • Patent number: 7750232
    Abstract: A multi-crystalline silicon germanium bulk crystal with microscopic compositional distribution is adapted for use in solar cells to substantially increase conversion efficiency. By controlling the average Ge concentration between 0.1 and 8.0 mole percent, significant improvements are attained with respect to short circuit current density and conversion efficiency.
    Type: Grant
    Filed: July 8, 2005
    Date of Patent: July 6, 2010
    Assignee: Sumco Solar Corporation
    Inventors: Kazuo Nakajima, Wugen Pan, Kozo Fujiwara, Noritaka Usami
  • Patent number: 7658175
    Abstract: An engine start device having a first start mode in which the engine is started on a spot by executing a start operation of the engine, and a second start mode in which a necessary accumulated force is previously accumulated in to start in one time in an optional place at an optional timing. In the first start mode, an accumulated force, accumulated by a rotation of a rotation drive section allows the engine to be started on the spot. If switched to the second start mode, the rotation of the rotation drive section is exclusively accumulated and released in the optional place at a desired time so as to start the engine in accordance with a one-touch operation.
    Type: Grant
    Filed: December 20, 2005
    Date of Patent: February 9, 2010
    Assignee: Zenoah Co., Ltd.
    Inventors: Yuu Sugishita, Kazuo Nakajima
  • Publication number: 20090000536
    Abstract: A high-quality polycrystalline bulk semiconductor having a large crystal grain size is produced by the casting method in which growth is regulated so as to proceed in the same plane direction, i.e., the {110}; plane or {112} plane is disclosed. The process, which is for producing a polycrystalline bulk semiconductor, comprises: a step in which a melt of a semiconductor selected among Si, Ge, and SiGe is held in a crucible; a step in which a bottom part of the crucible is cooled to give a temperature gradient and that part of the melt which is located directly on the crucible bottom is rapidly cooled in the beginning of growth to supercool the melt around the crucible bottom; a step in which the crucible is cooled to grow nuclei on the crucible bottom due to the supercooled state of the melt around the crucible bottom and thereby grow dendritic crystals along the crucible bottom; and a step in which a polycrystalline bulk of the semiconductor is then grown on the upper side of the dendritic crystals.
    Type: Application
    Filed: May 30, 2008
    Publication date: January 1, 2009
    Applicant: Tohoku University
    Inventors: Kozo Fujiwara, Kazuo Nakajima
  • Publication number: 20080283017
    Abstract: An engine start device having a first start mode in which the engine is started on a spot by executing a start operation of the engine, and a second start mode in which a necessary accumulated force is previously accumulated in to start in one time in an optional place at an optional timing. In the first start mode, an accumulated force, accumulated by a rotation of a rotation drive section allows the engine to be started on the spot. If switched to the second start mode, the rotation of the rotation drive section is exclusively accumulated and released in the optional place at a desired time so as to start the engine in accordance with a one-touch operation.
    Type: Application
    Filed: December 20, 2005
    Publication date: November 20, 2008
    Applicant: ZENOAH CO., LTD
    Inventors: Yuu Sugishita, Kazuo Nakajima
  • Patent number: 7422641
    Abstract: A soft spray nozzle discharging a cleaning mist is vertically directed and fixed to an arm. A rinse nozzle discharging rinsing deionized water for suppressing obstruction is vertically fixed to the arm at a prescribed distance from the soft spray nozzle. During cleaning, it follows that both nozzles discharge detergents while keeping relative layout relation. Therefore, the discharged cleaning mist and rinsing deionized water do not interfere with each other before reaching the substrate but the used detergents are entirely horizontally splashed and recovered in a cup. Thus, the cleaning mist is prevented from scattering and adhering to the periphery.
    Type: Grant
    Filed: October 30, 2002
    Date of Patent: September 9, 2008
    Assignee: Dainippon Screen Mfg. Co., Ltd.
    Inventors: Kazuo Nakajima, Masanobu Sato, Hiroaki Sugimoto, Akio Hashizume, Hiroki Tsujikawa
  • Patent number: 7314529
    Abstract: A soft spray nozzle discharging a cleaning mist is vertically directed and fixed to an arm. A rinse nozzle discharging rinsing deionized water for suppressing obstruction is vertically fixed to the arm at a prescribed distance from the soft spray nozzle. During cleaning, it follows that both nozzles discharge detergents while keeping relative layout relation. Therefore, the discharged cleaning mist and rinsing deionized water do not interfere with each other before reaching the substrate but the used detergents are entirely horizontally splashed and recovered in a cup. Thus, the cleaning mist is prevented from scattering and adhering to the periphery.
    Type: Grant
    Filed: December 29, 2004
    Date of Patent: January 1, 2008
    Assignee: Dainippon Screen Mfg. Co., Ltd.
    Inventors: Kazuo Nakajima, Masanobu Sato, Hiroaki Sugimoto, Akio Hashizume, Hiroki Tsujikawa