Patents by Inventor Kazunari Kurita

Kazunari Kurita 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: 11245014
    Abstract: Provided is a method of producing an epitaxial silicon wafer having high gettering capability resulting in even more reduced white spot defects in a back-illuminated solid-state imaging device. The method includes: a first step of irradiating a surface of a silicon wafer with cluster ions of CnHm (n=1 or 2, m=1, 2, 3, 4, or 5) generated using a Bernas ion source or an IHC ion source, thereby forming, in the silicon wafer, a modifying layer containing, as a solid solution, carbon and hydrogen that are constituent elements of the cluster ions; and a subsequent second step of forming a silicon epitaxial layer on the surface. In the first step, peaks of concentration profiles of carbon and hydrogen in the depth direction of the modifying layer are made to lie in a range of more than 150 nm and 2000 nm or less from the surface.
    Type: Grant
    Filed: August 24, 2018
    Date of Patent: February 8, 2022
    Assignee: SUMCO CORPORATION
    Inventors: Takeshi Kadono, Kazunari Kurita
  • Publication number: 20210083058
    Abstract: Provided is a method of producing an epitaxial silicon wafer having high gettering capability resulting in even more reduced white spot defects in a back-illuminated solid-state imaging device. The method includes: a first step of irradiating a surface of a silicon wafer with cluster ions of CnHm (n=1 or 2, m=1, 2, 3, 4, or 5) generated using a Bernas ion source or an IHC ion source, thereby forming, in the silicon wafer, a modifying layer containing, as a solid solution, carbon and hydrogen that are constituent elements of the cluster ions; and a subsequent second step of forming a silicon epitaxial layer on the surface. In the first step, peaks of concentration profiles of carbon and hydrogen in the depth direction of the modifying layer are made to lie in a range of more than 150 nm and 2000 nm or less from the surface.
    Type: Application
    Filed: August 24, 2018
    Publication date: March 18, 2021
    Applicant: SUMCO CORPORATION
    Inventors: Takeshi KADONO, Kazunari KURITA
  • Patent number: 10861709
    Abstract: Provided is a method of evaluating the impurity gettering capability of an epitaxial silicon wafer, which allows for very precise evaluation of the impurity gettering behavior of a modified layer formed immediately under an epitaxial layer, the modified layer containing carbon in solid solution. In this method, a modified layer located immediately under an epitaxial layer, the modified layer containing carbon in solid solution, is analyzed by three-dimensional atom probe microscopy, and the impurity gettering capability of the modified layer is evaluated based on a three-dimensional map of carbon in the modified layer, obtained by the analysis.
    Type: Grant
    Filed: January 12, 2018
    Date of Patent: December 8, 2020
    Assignee: SUMCO CORPORATION
    Inventors: Satoshi Shigematsu, Ryosuke Okuyama, Kazunari Kurita
  • Publication number: 20200203178
    Abstract: Provided is a method of evaluating the impurity gettering capability of an epitaxial silicon wafer, which allows for very precise evaluation of the impurity gettering behavior of a modified layer formed immediately under an epitaxial layer, the modified layer containing carbon in solid solution. In this method, a modified layer located immediately under an epitaxial layer, the modified layer containing carbon in solid solution, is analyzed by three-dimensional atom probe microscopy, and the impurity gettering capability of the modified layer is evaluated based on a three-dimensional map of carbon in the modified layer, obtained by the analysis.
    Type: Application
    Filed: January 12, 2018
    Publication date: June 25, 2020
    Applicant: SUMCO CORPORATION
    Inventors: Satoshi SHIGEMATSU, Ryosuke OKUYAMA, Kazunari KURITA
  • Publication number: 20200203418
    Abstract: Provided is a semiconductor epitaxial wafer having metal contamination reduced by achieving higher gettering capability, a method of producing the semiconductor epitaxial wafer, and a method of producing a solid-state image sensing device using the semiconductor epitaxial wafer. The method of producing a semiconductor epitaxial wafer 100 includes a first step of irradiating a semiconductor wafer 10 containing at least one of carbon and nitrogen with cluster ions 16 thereby forming a modifying layer 18 formed from a constituent element of the cluster ions 16 contained as a solid solution, in a surface portion of the semiconductor wafer 10; and a second step of forming a first epitaxial layer 20 on the modifying layer 18 of the semiconductor wafer 10.
    Type: Application
    Filed: December 17, 2019
    Publication date: June 25, 2020
    Applicant: SUMCO Corporation
    Inventors: Takeshi Kadono, Kazunari Kurita
  • Publication number: 20200127044
    Abstract: An object is to provide a method of producing a semiconductor epitaxial wafer having higher gettering capability and a reduced haze level of the surface of a semiconductor epitaxial layer. The method of producing a semiconductor epitaxial wafer, according to the present invention includes: a first step of irradiating a semiconductor wafer 10 with cluster ions 16 thereby forming a modifying layer 18 formed from a constituent element of the cluster ions 16 contained as a solid solution, in a surface portion 10A of the semiconductor wafer; a second step of performing heat treatment for crystallinity recovery on the semiconductor wafer 10 after the first step such that the haze level of the semiconductor wafer surface portion 10A is 0.20 ppm or less; and a third step of forming an epitaxial layer 20 on the modifying layer 18 of the semiconductor wafer after the second step.
    Type: Application
    Filed: December 17, 2019
    Publication date: April 23, 2020
    Applicant: SUMCO Corporation
    Inventors: Takeshi Kadono, Kazunari Kurita
  • Publication number: 20200127043
    Abstract: The present invention provides a method of producing a semiconductor epitaxial wafer, which can suppress metal contamination by achieving higher gettering capability. The method of producing a semiconductor epitaxial wafer includes a first step of irradiating a surface portion 10A of a semiconductor wafer 10 with cluster ions 16 thereby forming a modifying layer 18 formed from carbon and a dopant element contained as a solid solution that are constituent elements of the cluster ions 16, in the surface portion 10A of the semiconductor wafer; and a second step of forming an epitaxial layer 20 on the modifying layer 18 of the semiconductor wafer, the epitaxial layer 20 having a dopant element concentration lower than the peak concentration of the dopant element in the modifying layer 18.
    Type: Application
    Filed: December 17, 2019
    Publication date: April 23, 2020
    Applicant: SUMCO Corporation
    Inventors: Takeshi Kadono, Kazunari Kurita
  • Patent number: 10453682
    Abstract: Provided is an epitaxial wafer having an excellent gettering capability and a suppressed formation of epitaxial defects. The epitaxial wafer has a specified resistivity, and includes a modifying layer formed on a surface portion of the silicon wafer and composed of a predetermined element including at least carbon, in the form of a solid solution in the silicon wafer; and an epitaxial layer having a resistivity that is higher than the resistivity of the silicon wafer, wherein a concentration profile of the predetermined element in the modifying layer in a depth direction thereof meets a specified full width half maximum and a specified peak concentration.
    Type: Grant
    Filed: June 4, 2018
    Date of Patent: October 22, 2019
    Assignee: SUMCO CORPORATION
    Inventors: Takuro Iwanaga, Kazunari Kurita, Takeshi Kadono
  • Patent number: 10396120
    Abstract: A semiconductor epitaxial wafer production method that can increase the peak concentration of hydrogen in a surface portion of a semiconductor wafer after epitaxial layer formation is provided. A method of producing a semiconductor epitaxial wafer comprises: a first step of irradiating a surface of a semiconductor wafer with cluster ions containing hydrogen as a constituent element, to form a modifying layer formed from, as a solid solution, a constituent element of the cluster ions including hydrogen in a surface portion of the semiconductor wafer; a second step of, after the first step, irradiating the semiconductor wafer with electromagnetic waves of a frequency of 300 MHz or more and 3 THz or less, to heat the semiconductor wafer; and a third step of, after the second step, forming an epitaxial layer on the modifying layer of the semiconductor wafer.
    Type: Grant
    Filed: December 5, 2016
    Date of Patent: August 27, 2019
    Assignee: SUMCO CORPORATION
    Inventors: Takeshi Kadono, Kazunari Kurita
  • Patent number: 10224203
    Abstract: Provided is a method of producing a semiconductor epitaxial wafer having enhanced gettering ability. The method of producing a semiconductor epitaxial wafer includes: a first step of irradiating a surface of a semiconductor wafer with cluster ions to form a modified layer that is located in a surface portion of the semiconductor wafer and that includes a constituent element of the cluster ions in solid solution; and a second step of forming an epitaxial layer on the modified layer of the semiconductor wafer. The first step is performed in a state in which a temperature of the semiconductor wafer is maintained at lower than 25° C.
    Type: Grant
    Filed: November 25, 2015
    Date of Patent: March 5, 2019
    Assignee: SUMCO CORPORATION
    Inventors: Ryo Hirose, Ryosuke Okuyama, Kazunari Kurita
  • Publication number: 20180374891
    Abstract: A semiconductor epitaxial wafer production method that can increase the peak concentration of hydrogen in a surface portion of a semiconductor wafer after epitaxial layer formation is provided. A method of producing a semiconductor epitaxial wafer comprises: a first step of irradiating a surface of a semiconductor wafer with cluster ions containing hydrogen as a constituent element, to form a modifying layer formed from, as a solid solution, a constituent element of the cluster ions including hydrogen in a surface portion of the semiconductor wafer; a second step of, after the first step, irradiating the semiconductor wafer with electromagnetic waves of a frequency of 300 MHz or more and 3 THz or less, to heat the semiconductor wafer; and a third step of, after the second step, forming an epitaxial layer on the modifying layer of the semiconductor wafer.
    Type: Application
    Filed: December 5, 2016
    Publication date: December 27, 2018
    Applicant: SUMCO CORPORATION
    Inventors: Takeshi KADONO, Kazunari KURITA
  • Publication number: 20180286677
    Abstract: Provided is an epitaxial wafer having an excellent gettering capability and a suppressed formation of epitaxial defects. The epitaxial wafer has a specified resistivity, and includes a modifying layer formed on a surface portion of the silicon wafer and composed of a predetermined element including at least carbon, in the form of a solid solution in the silicon wafer; and an epitaxial layer having a resistivity that is higher than the resistivity of the silicon wafer, wherein a concentration profile of the predetermined element in the modifying layer in a depth direction thereof meets a specified full width half maximum and a specified peak concentration.
    Type: Application
    Filed: June 4, 2018
    Publication date: October 4, 2018
    Applicant: SUMCO CORPORATION
    Inventors: Takuro IWANAGA, Kazunari KURITA, Takeshi KADONO
  • Patent number: 10062569
    Abstract: Provided is a method of manufacturing an epitaxial wafer having an excellent gettering capability while suppressing formation of epitaxial defects. The method includes: a cluster ion irradiation step of irradiating a surface of a silicon wafer having a resistivity of from 0.001 ?·cm to 0.1 ?·cm with cluster ions containing at least carbon at a dose of from 2.0×1014/cm2 to 1.0×1016/cm2 to form, on a surface portion of the silicon wafer, a modifying layer composed of a constituent element of the cluster ions in the form of a solid solution; and an epitaxial layer forming step of forming, on the modifying layer on the silicon wafer, an epitaxial layer having a resistivity that is higher than the resistivity of the silicon wafer.
    Type: Grant
    Filed: December 10, 2014
    Date of Patent: August 28, 2018
    Assignee: SUMCO CORPORATION
    Inventors: Takuro Iwanaga, Kazunari Kurita, Takeshi Kadono
  • Patent number: 9847370
    Abstract: The present invention provides a method of more efficiently producing a semiconductor epitaxial wafer, which can suppress metal contamination by achieving higher gettering capability. A method of producing a semiconductor epitaxial wafer 100 according to the present invention includes a first step of irradiating a semiconductor wafer 10 with cluster ions 16 to form a modifying layer 18 formed from a constituent element of the cluster ions 16 in a surface portion 10A of the semiconductor wafer; and a second step of forming an epitaxial layer 20 on the modifying layer 18 of the semiconductor wafer 10.
    Type: Grant
    Filed: September 23, 2016
    Date of Patent: December 19, 2017
    Assignee: SUMCO Corporation
    Inventors: Takeshi Kadono, Kazunari Kurita
  • Publication number: 20170352545
    Abstract: Provided is a method of producing a semiconductor epitaxial wafer having enhanced gettering ability. The method of producing a semiconductor epitaxial wafer includes: a first step of irradiating a surface of a semiconductor wafer with cluster ions to form a modified layer that is located in a surface portion of the semiconductor wafer and that includes a constituent element of the cluster ions in solid solution; and a second step of forming an epitaxial layer on the modified layer of the semiconductor wafer. The first step is performed in a state in which a temperature of the semiconductor wafer is maintained at lower than 25° C.
    Type: Application
    Filed: November 25, 2015
    Publication date: December 7, 2017
    Applicant: SUMCO CORPORATION
    Inventors: Ryo HIROSE, Ryosuke OKUYAMA, Kazunari KURITA
  • Publication number: 20170256668
    Abstract: To provide a semiconductor epitaxial wafer having an epitaxial layer with excellent crystallinity, the semiconductor epitaxial wafer is a semiconductor epitaxial wafer in which an epitaxial layer is formed on a surface of a semiconductor wafer, and the peak of the hydrogen concentration profile detected by SIMS lies in a surface portion of the semiconductor wafer on the side where the on the side where the epitaxial layer is formed.
    Type: Application
    Filed: May 21, 2015
    Publication date: September 7, 2017
    Applicant: SUMCO CORPORATION
    Inventors: Ryosuke OKUYAMA, Takeshi KADONO, Kazunari KURITA
  • Publication number: 20170077171
    Abstract: The present invention provides a method of more efficiently producing a semiconductor epitaxial wafer, which can suppress metal contamination by achieving higher gettering capability. A method of producing a semiconductor epitaxial wafer 100 according to the present invention includes a first step of irradiating a semiconductor wafer 10 with cluster ions 16 to form a modifying layer 18 formed from a constituent element of the cluster ions 16 in a surface portion 10A of the semiconductor wafer; and a second step of forming an epitaxial layer 20 on the modifying layer 18 of the semiconductor wafer 10.
    Type: Application
    Filed: September 23, 2016
    Publication date: March 16, 2017
    Applicant: SUMCO Corporation
    Inventors: Takeshi Kadono, Kazunari Kurita
  • Publication number: 20160351393
    Abstract: Provided is a method of manufacturing an epitaxial wafer having an excellent gettering capability while suppressing formation of epitaxial defects. The method includes: a cluster ion irradiation step of irradiating a surface of a silicon wafer having a resistivity of from 0.001 ?·cm to 0.1 ?·cm with cluster ions containing at least carbon at a dose of from 2.0×1014/cm2 to 1.0×1016/cm2 to form, on a surface portion of the silicon wafer, a modifying layer composed of a constituent element of the cluster ions in the form of a solid solution; and an epitaxial layer forming step of forming, on the modifying layer on the silicon wafer, an epitaxial layer having a resistivity that is higher than the resistivity of the silicon wafer.
    Type: Application
    Filed: December 10, 2014
    Publication date: December 1, 2016
    Applicant: SUMCO CORPORATION
    Inventors: Takuro IWANAGA, Kazunari KURITA, Takeshi KADONO
  • Patent number: 9496139
    Abstract: The present invention provides a method of more efficiently producing a semiconductor epitaxial wafer, which can suppress metal contamination by achieving higher gettering capability. A method of producing a semiconductor epitaxial wafer 100 according to the present invention includes a first step of irradiating a semiconductor wafer 10 with cluster ions 16 to form a modifying layer 18 formed from a constituent element of the cluster ions 16 in a surface portion 10A of the semiconductor wafer; and a second step of forming an epitaxial layer 20 on the modifying layer 18 of the semiconductor wafer 10.
    Type: Grant
    Filed: March 19, 2012
    Date of Patent: November 15, 2016
    Assignee: SUMCO Corporation
    Inventors: Takeshi Kadono, Kazunari Kurita
  • Patent number: RE49657
    Abstract: Provided is an epitaxial wafer having an excellent gettering capability and a suppressed formation of epitaxial defects. The epitaxial wafer has a specified resistivity, and includes a modifying layer formed on a surface portion of the silicon wafer and composed of a predetermined element including at least carbon, in the form of a solid solution in the silicon wafer; and an epitaxial layer having a resistivity that is higher than the resistivity of the silicon wafer, wherein a concentration profile of the predetermined element in the modifying layer in a depth direction thereof meets a specified full width half maximum and a specified peak concentration.
    Type: Grant
    Filed: September 30, 2020
    Date of Patent: September 12, 2023
    Assignee: SUMCO CORPORATION
    Inventors: Takuro Iwanaga, Kazunari Kurita, Takeshi Kadono