Patents by Inventor Shoji Nishida

Shoji Nishida 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: 6802900
    Abstract: Provided are a liquid phase growth method including a step of immersing a substrate in a crucible storing a solvent having a growth material dissolved therein; and a step of cooling the solvent from an interior thereof, and a liquid phase growth apparatus for use in the method, by which a temperature difference of a solution is decreased and by which a deposited film is formed in a uniform thickness.
    Type: Grant
    Filed: December 20, 2001
    Date of Patent: October 12, 2004
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masaaki Iwane, Katsumi Nakagawa, Tetsuro Saito, Tatsumi Shoji, Takehito Yoshino, Shoji Nishida, Noritaka Ukiyo, Masaki Mizutani
  • Patent number: 6756289
    Abstract: To accomplish both of higher performance of a crystal and lower cost in a semiconductor member, and to produce a solar cell having a high efficiency and a flexible shape at low cost, the semiconductor member is produced by the following steps, (a) forming a porous layer in the surface region of a substrate, (b) immersing the porous layer into a melting solution in which elements for forming a semiconductor layer to be grown is dissolved, under a reducing atmosphere at a high temperature, to grow a crystal semiconductor layer on the surface of the porous layer, (c) bonding another substrate onto the surface of the substrate on which the porous layer and the semiconductor layer are formed and (d) separating the substrate from the another substrate at the porous layer.
    Type: Grant
    Filed: August 15, 2000
    Date of Patent: June 29, 2004
    Assignee: Canon Kabushiki Kaisha
    Inventors: Katsumi Nakagawa, Takao Yonehara, Shoji Nishida, Kiyofumi Sakaguchi
  • Publication number: 20040118337
    Abstract: According to the present invention, at the time of growing a silicon film by liquid epitaxy on a substrate, a bulk portion having substantially no void is formed and then a surface portion having plural protrusions that overhang in a lateral direction is formed. As a result, it is possible to form a silicon film having an uneven structure suitable for increasing optical path length on a surface layer of a semiconductor substrate without performing an additional process for forming an uneven structure. Therefore, it is possible to obtain a semiconductor substrate particularly suitable for a solar cell having an improved short circuit current property at low cost. Accordingly, it is possible to provide a solar cell having high efficiency and being low in price.
    Type: Application
    Filed: September 26, 2003
    Publication date: June 24, 2004
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Masaki Mizutani, Shunichi Ishihara, Katsumi Nakagawa, Takehito Yoshino, Shoji Nishida
  • Publication number: 20040118336
    Abstract: A liquid-phase growth process for continuously growing a crystal film on a plurality of substrates with respect to their one side surfaces, characterized in that said plurality of substrates are kept afloat on the surface of a flowing solution for liquid-phase epitaxy which comprises a crystallizing material dissolved in a solvent in a supersaturated state and which is flowing in a solution flow passage, and while said plurality of substrates being moved by virtue of said flowing solution in said solution flow passage, a crystal film is grown on the surfaces of said plurality of substrates which are in contact with said flowing solution. A liquid-phase growth apparatus suitable for practicing said liquid-phase growth process.
    Type: Application
    Filed: September 22, 2003
    Publication date: June 24, 2004
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Masaki Mizutani, Takehiko Yoshino, Shoji Nishida
  • Publication number: 20040087111
    Abstract: A method for manufacturing a semiconductor film includes a step of preparing a first member including a semiconductor substrate, a semiconductor layer, and a separation layer provided between the semiconductor substrate and the semiconductor layer, a step of bonding or attracting a second member which is hardly heated by induction heating, onto the semiconductor layer of the first member, and a step of separating the semiconductor layer from the semiconductor substrate at the separation layer by heating the semiconductor substrate by induction heating.
    Type: Application
    Filed: September 10, 2003
    Publication date: May 6, 2004
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Yukiko Iwasaki, Tatsumi Shoji, Shoji Nishida
  • Patent number: 6720237
    Abstract: A method for manufacturing a semiconductor film includes a step of preparing a first member including a semiconductor substrate, a semiconductor layer, and a separation layer provided between the semiconductor substrate and the semiconductor layer, a step of bonding or attracting a second member which is hardly heated by induction heating, onto the semiconductor layer of the first member, and a step of separating semiconductor layer from the semiconductor substrate at the separation layer by heating the semiconductor substrate by induction heating.
    Type: Grant
    Filed: February 27, 2002
    Date of Patent: April 13, 2004
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yukiko Iwasaki, Tatsumi Shoji, Shoji Nishida
  • Publication number: 20040065251
    Abstract: With respect to a liquid phase growth method for a silicon crystal in which the silicon crystal is grown on a substrate by immersing the substrate in a solvent or allowing the substrate to contact the solvent, a gas containing a raw material and/or a dopant is supplied to the solvent after at least a part of the gas is decomposed by application of energy thereto. In this manner, a liquid phase growth method for a silicon crystal, the method capable of achieving continuous growth and suitable for mass production, a manufacturing method for a solar cell and a liquid phase growth apparatus for a silicon crystal are provided.
    Type: Application
    Filed: October 2, 2003
    Publication date: April 8, 2004
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Shoji Nishida, Takehito Yoshino, Masaaki Iwane, Masaki Mizutani
  • Publication number: 20040055894
    Abstract: In a process for producing a semiconductor member, and a solar cell, making use of a thin-film crystal semiconductor layer, the process comprises the steps of: (1) anodizing the surface of a first substrate to form a porous layer at least on one side of the substrate, (2) forming a semiconductor layer at least on the-surface of the porous layer, (3) removing the semiconductor layer at its peripheral region, (4) bonding a second substrate to the surface of the semiconductor layer, (5) separating the semiconductor layer from the first substrate at the part of the porous layer, and (6) treating the surface of the first substrate after separation and repeating the above steps (1) to (5).
    Type: Application
    Filed: September 24, 2003
    Publication date: March 25, 2004
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Yukiko Iwasaki, Shoji Nishida, Kiyofumi Sakaguchi, Noritaka Ukiyo
  • Publication number: 20040048411
    Abstract: Metal-grade silicon is melted and solidified in a mold to form a plate-shaped silicon layer and a crystalline silicon layer is made thereon, thereby providing a cheap solar cell without a need for a slicing step.
    Type: Application
    Filed: March 3, 2003
    Publication date: March 11, 2004
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Shoji Nishida
  • Patent number: 6682990
    Abstract: The separation method of a semiconductor layer according to the present invention comprises separating a semiconductor layer and a semiconductor substrate at a separation layer formed therebetween, wherein a face of the semiconductor layer at the side opposite to the separation layer and/or a face of the semiconductor substrate at the side opposite to the separation layer are held by utilizing an ice layer, whereby it is unnecessary to use an adhesive as holding means and at the same time it is possible to easily and uniformly separate them.
    Type: Grant
    Filed: September 7, 2000
    Date of Patent: January 27, 2004
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masaaki Iwane, Katsumi Nakagawa, Makoto Iwakami, Shoji Nishida, Noritaka Ukiyo, Yukiko Iwasaki, Masaki Mizutani
  • Publication number: 20030230231
    Abstract: A liquid-phase growth process comprising immersing a base substrate in a solution containing reactant species to be grown dissolved therein which is accommodated in a crucible and growing a crystal film on said substrate, characterized in that a capping member is kept afloat on the surface of said solution before said substrate is immersed in said solution and said capping member is subsided in said solution upon immersing said substrate in said solution. A liquid-phase growth apparatus suitable for practicing said liquid-phase growth process.
    Type: Application
    Filed: March 28, 2003
    Publication date: December 18, 2003
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Masaki Mizutani, Katsumi Nakagawa, Tetsuro Saito, Tatsumi Shoji, Takehito Yoshino, Shoji Nishida
  • Patent number: 6664169
    Abstract: In a process for producing a semiconductor member, and a solar cell, making use of a thin-film crystal semiconductor layer, the process includes the steps of: (1) anodizing the surface of a first substrate to form a porous layer at least on one side of the substrate, (2) forming a semiconductor layer at least on the surface of the porous layer, (3) removing the semiconductor layer at its peripheral region, (4) bonding a second substrate to the surface of the semiconductor layer, (5) separating the semiconductor layer from the first substrate at the part of the porous layer, and (6) treating the surface of the first substrate after separation and repeating the above steps (1) to (5).
    Type: Grant
    Filed: June 5, 2000
    Date of Patent: December 16, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yukiko Iwasaki, Shoji Nishida, Kiyofumi Sakaguchi, Noritaka Ukiyo
  • Publication number: 20030203547
    Abstract: A process for producing a semiconductor article is provided which comprises the steps of bonding a film onto a substrate having a porous semiconductor layer, and separating the film from the substrate at the porous semiconductor layer by applying a force to the film in a peeling direction.
    Type: Application
    Filed: January 9, 2003
    Publication date: October 30, 2003
    Inventors: Kiyofumi Sakaguchi, Takao Yonehara, Shoji Nishida, Kenji Yamagata
  • Publication number: 20030188680
    Abstract: A liquid-phase growth method for immersing a polycrystalline substrate in a melt in a crucible wherein crystal ingredients are dissolved, thereby growing poly crystals upon the substrate, comprises a first step for growing poly crystals to a predetermined thickness, and a second step for melting back a part of the poly crystals grown in the first step in the melt, wherein the relative position between the substrate and melt is changed between the first step and second step, bringing melt with different temperature into contact with the polycrystalline surface. The obtained poly crystals have properties rivaling those of poly crystals used in conventional solar cells but with little risk of trouble such as line breakage of grid electrodes in application to solar cells, and can be obtained in great quantities at low costs.
    Type: Application
    Filed: March 27, 2003
    Publication date: October 9, 2003
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Katsumi Nakagawa, Shunichi Ishihara, Hiroshi Sato, Shoji Nishida, Yasuyoshi Takai
  • Publication number: 20030183154
    Abstract: A liquid-phase growth apparatus for growing a crystal on a substrate includes a crucible containing a solution that contains a raw material for forming the crystal, and a substrate holder for vertically holding the substrate. The substrate holder includes connectors, a receiving component, and a push component. The receiving component and the push component are opposite to each other and are connected by the connectors. The push component holds an upper portion of the substrate while the receiving component holds a lower portion of the substrate. The substrate holder containing the vertically held substrate is dipped into the solution. The receiving component ascends with buoyancy in the solution contained in the crucible, so that the substrate is now held securely and prevented from cracking due to thermal expansion.
    Type: Application
    Filed: March 12, 2003
    Publication date: October 2, 2003
    Inventors: Masaki Mizutani, Katsumi Nakagawa, Takehito Yoshino, Shoji Nishida
  • Publication number: 20030183159
    Abstract: A process for producing a single crystal silicon wafer, comprising the steps of forming a porous layer on a single crystal silicon substrate comprising a silicon whose concentration of mass number 28 silicon isotope is less than 92.5% on an average; dissolving a starting silicon whose concentration of mass number 28 silicone isotope whose mass number is more than 98% on an average in a melt for liquid-phase epitaxy until said starting silicon becomes to be a supersaturated state in said melt under reductive atmosphere maintained at high temperature: immersing said single crystal silicon substrate in said melt to grow a single crystal silicon layer on the surface of said porous layer of said single crystal silicon substrate; and peeling said single crystal silicon layer from a portion of said porous layer.
    Type: Application
    Filed: March 31, 2003
    Publication date: October 2, 2003
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Katsumi Nakagawa, Takao Yonehara, Kazuaki Ohmi, Shoji Nishida
  • Patent number: 6602767
    Abstract: A method for transferring a porous layer includes forming a porous layer on one side of a crystalline silicon member by anodization, fixing a supporting substrate onto the surface of the porous layer, and applying force to any one of the supporting substrate and the porous layer, whereby at least part of the porous layer is cleaved from the crystalline silicon member and is transferred onto the supporting substrate. The crystalline silicon member can be recycled and this method is suitable for mass production of semiconductor devices or solar batteries at low cost.
    Type: Grant
    Filed: January 26, 2001
    Date of Patent: August 5, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shoji Nishida, Katsumi Nakagawa, Takao Yonehara, Kiyofumi Sakaguchi
  • Publication number: 20030140859
    Abstract: To provide a method and an apparatus for producing semiconductor thin films in which the semiconductor thin films are allowed to grow on a plurality of substrates by dipping the plurality of substrates into a solution filled in a crucible, the solution containing a semiconductor as a solute, while moving the same in the solution, and an angle between a direction of a normal line on a central portion of a growing surface of each substrate and the direction of the movement of the substrates is set to be in 87 degrees or less and the movement of the substrates generates a flow of the solution. Thereby, in mass production of large-area devices such as solar cells, at the time of conducting liquid phase growth of semiconductor layers by the use of the dipping process, the above method and apparatus make it possible to treat a plurality of substrates together while ensuring the uniform thickness of a film produced and improvement in film forming rate, which leads to improvement in mass productivity.
    Type: Application
    Filed: February 12, 2003
    Publication date: July 31, 2003
    Inventors: Noritaka Ukiyo, Tetsuro Saito, Tatsumi Shoji, Makoto Iwakami, Takehito Yoshino, Shoji Nishida, Masaaki Iwane, Masaki Mizutani
  • Patent number: 6566235
    Abstract: A process for producing a semiconductor member, comprising a first step of forming a porous layer by making porous a first member at its surface portion, leaving some region or regions thereof not made porous; a second step of bonding a semiconductor layer formed on the porous layer and on the first-member surface left not made porous, to a second member to form a bonded structure; and a third step of separating the bonded structure at the part of the porous layer. The first member is made porous leaving some region or regions thereof not made porous so that the porous layer does not cause any separation at the part of the porous layer in the first and second steps. This process can make the semiconductor layer unseparable from the single-crystal silicon member before the separation for transferring the semiconductor layer to the support member side, without setting the anodizing conditions strictly. Also disclosed is a process for producing a solar cell by the above process.
    Type: Grant
    Filed: March 29, 2001
    Date of Patent: May 20, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shoji Nishida, Takao Yonehara, Kiyofumi Sakaguchi, Noritaka Ukiyo, Yukiko Iwasaki
  • Patent number: 6566277
    Abstract: The present invention provides a method for producing a semiconductor substrate which comprises the steps of growing a first semiconductor layer on a substrate in liquid phase at a properly controlled temperature for eliminating defects and growing a second semiconductor layer on the first semiconductor layer in liquid phase at a higher temperature; a solar cell produced by a method comprising a step of anodizing the surface of the first and second layer side of the semiconductor substrate produced by the liquid-phase growth method; a liquid-phase growth apparatus comprising means for storing a melt, means for changing the temperature of the stored melt, and means for bringing an oxygen-containing substrate into contact with the melt, wherein a substrate is brought into contact with the melt at a temperature so as to suppress the stacking faults contained in the semiconductor layer grown on the surface of the substrate.
    Type: Grant
    Filed: September 18, 2000
    Date of Patent: May 20, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Katsumi Nakagawa, Shoji Nishida