Patents by Inventor Kiyofumi Sakaguchi

Kiyofumi Sakaguchi 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: 6613678
    Abstract: A process for manufacturing a semiconductor substrate, comprising the step of preparing a first substrate which has a surface layer portion subjected to hydrogen annealing, the separation-layer formation step of implanting ions of hydrogen or the like into the first substrate from the side of the surface layer portion, thereby to form a separation layer, the adhesion step of bonding the first substrate and a second substrate to each other so that the surface layer portion may lie inside, thereby to form a multilayer structure, and the transfer step of separating the multilayer structure by utilizing the separation layer, thereby to transfer the less-defective layer of the surface layer portion onto the second substrate. The less-defective layer is a single-crystal silicon layer in which defects inherent in a bulk wafer, such as COPs and FPDs, are decreased.
    Type: Grant
    Filed: May 17, 1999
    Date of Patent: September 2, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kiyofumi Sakaguchi, Takao Yonehara, Nobuhiko Sato
  • Publication number: 20030159644
    Abstract: A process for manufacturing a semiconductor wafer which has superior suitability for mass production and reproducibility. The process comprises the steps of preparing a first member which has a monocrystalline semiconductor layer on a semiconductor substrate with a separation layer arranged therebetween with a semiconductor wafer as the raw material, transferring the monocrystalline semiconductor layer onto a second member which comprises a semiconductor wafer after separating the monocrystalline semiconductor layer through the separation layer, and smoothing the surface of the semiconductor substrate after the transferring step so as to be used as a semiconductor wafer for purposes other than forming the first and second members.
    Type: Application
    Filed: December 3, 1999
    Publication date: August 28, 2003
    Inventors: TAKAO YONEHARA, KUNIO WATANABE, TETSUYA SHIMADA, KAZUAKI OHMI, KIYOFUMI SAKAGUCHI
  • Patent number: 6609446
    Abstract: When a bonded substrate stack prepared by bonding a first substrate in which a single-crystal Si layer is formed on a porous layer, and an insulating layer is formed on the single-crystal Si layer to a second substrate is to be separated at the porous layer, serrate defects at the peripheral portion of the separated substrates are prevented. A fluid is ejected from an ejection nozzle (112) and injected into the porous layer of a bonded substrate stack (30) while rotating the bonded substrate stack (30) about an axis (C) in a direction (R), thereby separating the bonded substrate stack (30) into two substrates at the porous layer. When the peripheral portion of the bonded substrate stack (30) is to be separated, the ejection nozzle (112) is located within a range (B).
    Type: Grant
    Filed: February 1, 2000
    Date of Patent: August 26, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazuaki Ohmi, Takao Yonehara, Kiyofumi Sakaguchi, Kazutaka Yanagita, Hirokazu Kurisu
  • Patent number: 6609553
    Abstract: This invention prevents defects generated when a bonded substrate stack having a separation layer is separated. A bonded substrate stack (101) having a porous layer (101b) is separated in two steps of the first and second processes. In the first process, a jet is ejected to the porous layer (101b) while rotating the bonded substrate stack (101) to partially separate the bonded substrate stack (101) while leaving the central portion of the porous layer (101b) as an unseparated region. In the second process, the jet is ejected to the porous layer (101b) while rotation of the bonded substrate stack (101) is stopped. A force is applied to the unseparated region from a predetermined direction to completely separate the bonded substrate stack (101). Also, the first region (peripheral portion) and second region (central portion) of the bonded substrate stack (101) having the porous layer (101b) are separated using a jet and ultrasonic wave, respectively.
    Type: Grant
    Filed: June 20, 2002
    Date of Patent: August 26, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazutaka Yanagita, Takao Yonehara, Kazuaki Omi, Kiyofumi Sakaguchi
  • Patent number: 6605518
    Abstract: To cause a crack at a fixed position in a separation layer, a method of separating a composite member includes the steps of forming a separation layer inside a composite member, forming inside the separation layer a stress riser layer in which an in-plane stress has concentratedly been produced to an extent that does not cause separation by the in-plane stress, and enlarging the in-plane stress to cause a crack in the stress riser layer, thereby separating the composite member.
    Type: Grant
    Filed: April 26, 2000
    Date of Patent: August 12, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazuaki Ohmi, Katsumi Nakagawa, Nobuhiko Sato, Kiyofumi Sakaguchi, Kazutaka Yanagita, Takao Yonehara
  • 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
  • Patent number: 6597039
    Abstract: A composite member containing a separation area inside. A mechanical strength of the separation area is non-uniform along a surface of the composite member or along a bonded face. A mechanical strength of a peripheral portion of the separation area is locally low.
    Type: Grant
    Filed: December 18, 2001
    Date of Patent: July 22, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazuaki Ohmi, Kiyofumi Sakaguchi, Kazutaka Yanagita
  • Publication number: 20030116275
    Abstract: This invention is to provide a technique of separating bonded substrate stacks having porous layers at a high yield. A separating apparatus (100) has a pair of substrate holding portions (270, 280). A bonded substrate stack (50) is sandwiched from upper and lower sides and horizontally held by the substrate holding portions (270, 280) and rotated. A jet is ejected from a nozzle (260) and injected into the porous layer of the bonded substrate stack (50), thereby separating the bonded substrate stack (50) into two substrates at the porous layer. Another separating apparatus (5000) has a pair of substrate holding portions (270, 280), a nozzle (260) of rejecting a fluid to the porous layer of a bonded substrate stack (50), and an abrupt operation prevention mechanism (4000) for preventing the lower substrate holding portion (280) from abruptly moving downward but allowing it to moderately move when separating the bonded substrate stack (50).
    Type: Application
    Filed: December 27, 2002
    Publication date: June 26, 2003
    Inventors: Kazutaka Yanagita, Kazuaki Ohmi, Kiyofumi Sakaguchi
  • Publication number: 20030102082
    Abstract: This invention is to provide an apparatus for separating a substrate having a porous layer at the porous layer. A bonded substrate stack (101) having a porous layer (101b) is supported by substrate holding portions (120, 150) while being rotated. High-speed, high-pressure water (jet) is ejected from a nozzle (102), so the jet is injected into the bonded substrate stack (101). The substrate holding portions (120, 150) hold the bonded substrate stack (101) such that the bonded substrate stack (101) can expand at its central portion due to the pressure of the injected water. This efficiently applies a force (separation force) that acts outward from the inside of the bonded substrate stack (101).
    Type: Application
    Filed: December 12, 2002
    Publication date: June 5, 2003
    Inventors: Kazutaka Yanagita, Takao Yonehara, Kazuaki Omi, Kiyofumi Sakaguchi
  • Patent number: 6569748
    Abstract: There are provided a method of producing an SOI wafer of high quality with excellent controllability, productivity and economy and a wafer produced by such a method. In the method of producing a substrate utilizing wafer bonding, a first substrate member and a second substrate member are mutually bonded, and then the second substrate member is separated from the first substrate member at the interface of a first layer and a second layer formed on the main surface of the first substrate member, whereby the second layer is transferred onto the second substrate member. In the separation, the separation position at the interface of the first and the second layers is ensured by varying the porosity of a porous Si layer, forming an easily separable plane by the coagulation of pores in porous Si, effecting ion implantation to the interface or utilizing a heteroepitaxial interface.
    Type: Grant
    Filed: November 7, 2000
    Date of Patent: May 27, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kiyofumi Sakaguchi, Nobuhiko Sato
  • 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
  • Publication number: 20030089455
    Abstract: This invention is to prevent a substrate from dropping when it is transferred/received to/from a separating apparatus. The support surfaces of substrate holding portions (22, 23) are made horizontal, and a substrate (21) to be separated is mounted on one substrate holding portion (22) in a horizontal state (2A). The substrate holding portions (22, 23) are pivoted about rotary shafts (26, 27), respectively, to make the support surfaces of the substrate holding portions (22, 23) vertical so that the substrate (21) is sandwiched by the substrate holding portions (22, 23) (2B) The substrate holding portions (22, 23) are rotated about rotary shafts (24, 25), respectively, and simultaneously, high-pressure, high-speed water is ejected from an ejection nozzle (28) to separate the substrate (21) into two substrates (21a, 21c). The substrate holding portions (22, 23) are pivoted about the rotary shafts (26, 27), respectively, to make the support surfaces horizontal (2C).
    Type: Application
    Filed: December 9, 2002
    Publication date: May 15, 2003
    Inventors: Kiyofumi Sakaguchi, Takao Yonehara, Kazuaki Omi, Kazutaka Yanagita, Toshikazu Miyakogawa
  • Publication number: 20030087503
    Abstract: A method for making a thin film semiconductor. The method includes the steps of making a semiconductor substrate having one or more layers of different porosity, and subsequently separating the layers along a line of relative weakness. This method is particularly well adapted to manufacturing Silicon-on-Insulator (SOI) structures.
    Type: Application
    Filed: March 1, 2002
    Publication date: May 8, 2003
    Applicant: Canon Kabushiki Kaisha
    Inventors: Kiyofumi Sakaguchi, Takao Yonehara, Nobuhiko Sato
  • Patent number: 6540861
    Abstract: This invention is to prevent a substrate from dropping when it is transferred/received to/from a separating apparatus. The support surfaces of substrate holding portions (22, 23) are made horizontal, and a substrate (21) to be separated is mounted on one substrate holding portion (22) in a horizontal state (2A). The substrate holding portions (22, 23) are pivoted about rotary shafts (26, 27), respectively, to make the support surfaces of the substrate holding portions (22, 23) vertical so that the substrate (21) is sandwiched by the substrate holding portions (22, 23) (2B). The substrate holding portions (22, 23) are rotated about rotary shafts (24, 25), respectively, and simultaneously, high-pressure, high-speed water is ejected from an ejection nozzle (28) to separate the substrate (21) into two substrates (21a, 21c). The substrate holding portions (22, 23) are pivoted about the rotary shafts (26, 27), respectively, to make the support surfaces horizontal (2C).
    Type: Grant
    Filed: March 24, 1999
    Date of Patent: April 1, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kiyofumi Sakaguchi, Takao Yonehara, Kazuaki Omi, Kazutaka Yanagita, Toshikazu Miyakogawa
  • Patent number: 6534382
    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: Grant
    Filed: August 8, 2000
    Date of Patent: March 18, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kiyofumi Sakaguchi, Takao Yonehara, Shoji Nishida, Kenji Yamagata
  • Patent number: 6534336
    Abstract: The present invention provides a production method of a photoelectric conversion device, which comprises a step of forming an uneven shape on a surface of a substrate, a step of providing a separation layer maintaining the uneven shape on the substrate, a step of forming a semiconductor film maintaining the uneven shape on the separation layer, and a step of separating the semiconductor film from the substrate at the separation layer, wherein the step of forming the uneven shape on the surface of the substrate is a step of forming the substrate having the uneven shape on the surface by anisotropic etching of the substrate with the separation layer remaining after the separation. The present invention also provides a photoelectric conversion device produced by the above method.
    Type: Grant
    Filed: May 18, 2000
    Date of Patent: March 18, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masaaki Iwane, Takao Yonehara, Shoji Nishida, Kiyofumi Sakaguchi
  • Patent number: 6527031
    Abstract: This invention is to provide a technique of separating bonded substrate stacks having porous layers at a high yield. A separating apparatus (100) has a pair of substrate holding portions (270, 280). A bonded substrate stack (50) is sandwiched from upper and lower sides and horizontally held by the substrate holding portions (270, 280) and rotated. A jet is ejected from a nozzle (260) and injected into the porous layer of the bonded substrate stack (50), thereby separating the bonded substrate stack (50) into two substrates at the porous layer. Another separating apparatus (5000) has a pair of substrate holding portions (270, 280), a nozzle (260) of rejecting a fluid to the porous layer of a bonded substrate stack (50), and an abrupt operation prevention mechanism (4000) for preventing the lower substrate holding portion (280) from abruptly moving downward but allowing it to moderately move when separating the bonded substrate stack (50).
    Type: Grant
    Filed: November 5, 1999
    Date of Patent: March 4, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazutaka Yanagita, Kazuaki Ohmi, Kiyofumi Sakaguchi
  • Publication number: 20030038383
    Abstract: The present invention provides a semiconductor substrate comprising a semiconductor layer 3 formed on a supporting substrate 1 with interposition of an insulating layer 3 therebetween, wherein a mark is formed in a region other than a surface region of the semiconductor layer; and a process for producing the semiconductor substrate.
    Type: Application
    Filed: June 25, 2002
    Publication date: February 27, 2003
    Inventor: Kiyofumi Sakaguchi
  • Patent number: 6521078
    Abstract: This invention is to provide an apparatus for separating a substrate having a porous layer at the porous layer. A bonded substrate stack (101) having a porous layer (10b) is supported by substrate holding portions (120, 150) while being rotated. High-speed, high-pressure water (jet) is ejected from a nozzle (102), so the jet is injected into the bonded substrate stack (101). The substrate holding portions (120, 150) hold the bonded substrate stack (101) such that the bonded substrate stack (101) can expand at its central portion due to the pressure of the injected water. This efficiently applies a force (separation force) that acts outward from the inside of the bonded substrate stack (101).
    Type: Grant
    Filed: May 20, 2002
    Date of Patent: February 18, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazutaka Yanagita, Takao Yonehara, Kazuaki Omi, Kiyofumi Sakaguchi
  • Publication number: 20030010445
    Abstract: This invention is to appropriately separate a bonded substrate stack regardless of some distortion in the bonded substrate stack or the like. This separating apparatus includes a first nozzle which forms a jet with a large width and a second nozzle which forms a jet with a small width. When the outer portion of a bonded substrate stack is to be separated, a jet formed by the first nozzle is used. After that, when a portion inside the outer portion is to be separated, a jet formed by the second nozzle is used.
    Type: Application
    Filed: June 25, 2002
    Publication date: January 16, 2003
    Inventors: Kazutaka Yanagita, Mitsuharu Kohda, Kiyofumi Sakaguchi, Akira Fujimoto