Patents by Inventor Kouhei Sasamoto

Kouhei Sasamoto 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: 11774845
    Abstract: In a photomask blank including a transparent substrate and a first inorganic film containing either or both of a transition metal and silicon, and optional a second inorganic film containing either or both of a transition metal and silicon, when an intensity of secondary ions is measured in the thickness direction of the transparent substrate and the inorganic films by TOF-SIMS with using a primary ion source of Bi and a sputtering ion source of Cs, an intensity of secondary ions containing carbon detected at the interface of the transparent substrate and the inorganic film or the inorganic films is higher than both intensities of the secondary ions containing carbon detected, respectively, at the sides remote from the interface.
    Type: Grant
    Filed: June 22, 2021
    Date of Patent: October 3, 2023
    Assignee: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Kouhei Sasamoto, Hideo Kaneko
  • Publication number: 20220229358
    Abstract: The present invention provides a photomask blank which exhibits high adhesion of a resist film to a film containing chromium, and which is capable of achieving good resolution limit and good CD linearity during the formation of an assist pattern of a line pattern, said assist pattern supplementing the resolution of the main pattern of a photomask.
    Type: Application
    Filed: April 20, 2020
    Publication date: July 21, 2022
    Applicant: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Naoki MATSUHASHI, Kouhei SASAMOTO
  • Publication number: 20210407803
    Abstract: A photomask is manufactured from a photomask blank including a transparent substrate, a first inorganic film which comprises silicon and is free of chromium, and a second inorganic film which comprises chromium and is free of silicon, and is in contact with the first inorganic film by a method including steps of forming a pattern of the second inorganic film by fluorine-based dry etching with using a resist pattern, and forming a pattern of the first inorganic film by fluorine-based dry etching with using the pattern of the second inorganic film.
    Type: Application
    Filed: June 22, 2021
    Publication date: December 30, 2021
    Applicant: Shin-Etsu Chemical Co., Ltd.
    Inventor: Kouhei SASAMOTO
  • Publication number: 20210405520
    Abstract: In a photomask blank including a transparent substrate and a first inorganic film containing either or both of a transition metal and silicon, and optional a second inorganic film containing either or both of a transition metal and silicon, when an intensity of secondary ions is measured in the thickness direction of the transparent substrate and the inorganic films by TOF-SIMS with using a primary ion source of Bi and a sputtering ion source of Cs, an intensity of secondary ions containing carbon detected at the interface of the transparent substrate and the inorganic film or the inorganic films is higher than both intensities of the secondary ions containing carbon detected, respectively, at the sides remote from the interface.
    Type: Application
    Filed: June 22, 2021
    Publication date: December 30, 2021
    Applicant: Shin-Etsu Chemical Co., Ltd.
    Inventors: Kouhei SASAMOTO, Hideo KANEKO
  • Patent number: 11143949
    Abstract: Provided is a photomask blank including, on a substrate, a processing film and a film made of a material containing chromium which is formed to be in contact with the processing film and has a three-layer structure of first, second and third layers, each of which contains chromium, oxygen, and nitrogen, wherein the first layer has a chromium content of 40 atomic % or less, an oxygen content of 50 atomic % or more, a nitrogen content of 10 atomic % or less, and a thickness of 20 nm or more, the second layer has a chromium content of 50 atomic % or more, an oxygen content of 20 atomic % or less, and a nitrogen content of 30 atomic % or more, and the third layer has a chromium content of 40 atomic % or less, an oxygen content of 50 atomic % or more, and a nitrogen content of 10 atomic % or less.
    Type: Grant
    Filed: May 22, 2019
    Date of Patent: October 12, 2021
    Assignee: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Yukio Inazuki, Kouhei Sasamoto
  • Patent number: 11131920
    Abstract: A photomask blank for a material of a photomask used in pattern transfer by exposure light having a wavelength of up to 250 nm, including a transparent substrate, a chromium-containing film directly formed on the substrate or formed with an optical film intervened between the transparent substrate and the chromium-containing film. The chromium-containing film includes a region (A) composed of a chromium compound containing chromium, oxygen and carbon, wherein each of contents of the elements contained in the chromium compound is continuously varied in the thickness direction of the region (A), and toward the substrate, the content of chromium increases, and the content of carbon decreases.
    Type: Grant
    Filed: November 22, 2019
    Date of Patent: September 28, 2021
    Assignee: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Yukio Inazuki, Kouhei Sasamoto, Naoki Matsuhashi
  • Patent number: 10989999
    Abstract: A halftone phase shift mask blank comprising a transparent substrate and a halftone phase shift film thereon is provided. The halftone phase shift film includes at least one layer composed of a silicon base material having a transition metal content ?3 at %, a Si+N+O content ?90 at %, a Si content of 30-70 at %, a N+O content of 30-60 at %, and an O content ?30 at %, and having a sheet resistance ?1013/?/?. The halftone phase shift film undergoes minimal pattern size variation degradation upon exposure to sub-200 nm radiation, and has chemical resistance and improved processability.
    Type: Grant
    Filed: September 27, 2019
    Date of Patent: April 27, 2021
    Assignee: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Yukio Inazuki, Takuro Kosaka, Kouhei Sasamoto, Hideo Kaneko
  • Patent number: 10788747
    Abstract: A photomask blank comprising a transparent substrate and a Cr-containing film is provided. The Cr-containing film includes a layer which is composed of a C-containing Cr compound and further contains O or O and N. The layer has a C/Cr atomic ratio of at least 0.3 and a N/Cr atomic ratio of up to 0.1, and has a Cr content of up to 50 at % and a C/O atomic ratio of at least 0.8, or a Cr content of up to 60 at % and a C/O atomic ratio of at least 1. The photomask blank is processed into a photomask by dry etching the Cr-containing film.
    Type: Grant
    Filed: November 1, 2018
    Date of Patent: September 29, 2020
    Assignee: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Yukio Inazuki, Kouhei Sasamoto, Naoki Matsuhashi
  • Patent number: 10782608
    Abstract: A method for preparing a photomask blank comprising a transparent substrate and a chromium-containing film contiguous thereto involves the step of depositing the chromium-containing film by sputtering a metallic chromium target having an Ag content of up to 1 ppm. When a photomask prepared from the photomask blank is repeatedly used in patternwise exposure to ArF excimer laser radiation, the number of defects formed on the photomask is minimized.
    Type: Grant
    Filed: January 30, 2018
    Date of Patent: September 22, 2020
    Assignee: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Yukio Inazuki, Kouhei Sasamoto, Tsutomu Yuri
  • Publication number: 20200192215
    Abstract: A photomask blank for a material of a photomask used in pattern transfer by exposure light having a wavelength of up to 250 nm, including a transparent substrate, a chromium-containing film directly formed on the substrate or formed with an optical film intervened between the transparent substrate and the chromium-containing film. The chromium-containing film includes a region (A) composed of a chromium compound containing chromium, oxygen and carbon, wherein each of contents of the elements contained in the chromium compound is continuously varied in the thickness direction of the region (A), and toward the substrate, the content of chromium increases, and the content of carbon decreases.
    Type: Application
    Filed: November 22, 2019
    Publication date: June 18, 2020
    Applicant: Shin-Etsu Chemical Co., Ltd.
    Inventors: Yukio INAZUKI, Kouhei SASAMOTO, Naoki MATSUHASHI
  • Publication number: 20200026181
    Abstract: A halftone phase shift mask blank comprising a transparent substrate and a halftone phase shift film thereon is provided. The halftone phase shift film includes at least one layer composed of a silicon base material having a transition metal content ?3 at %, a Si+N+O content ?90 at %, a Si content of 30-70 at %, a N+O content of 30-60 at %, and an O content ?30 at %, and having a sheet resistance ?1013/?/?. The halftone phase shift film undergoes minimal pattern size variation degradation upon exposure to sub-200 nm radiation, and has chemical resistance and improved processability.
    Type: Application
    Filed: September 27, 2019
    Publication date: January 23, 2020
    Applicant: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Yukio INAZUKI, Takuro KOSAKA, Kouhei SASAMOTO, Hideo KANEKO
  • Publication number: 20190369482
    Abstract: Provided is a photomask blank including, on a substrate, a processing film and a film made of a material containing chromium which is formed to be in contact with the processing film and has a three-layer structure of first, second and third layers, each of which contains chromium, oxygen, and nitrogen, wherein the first layer has a chromium content of 40 atomic % or less, an oxygen content of 50 atomic % or more, a nitrogen content of 10 atomic % or less, and a thickness of 20 nm or more, the second layer has a chromium content of 50 atomic % or more, an oxygen content of 20 atomic % or less, and a nitrogen content of 30 atomic % or more, and the third layer has a chromium content of 40 atomic % or less, an oxygen content of 50 atomic % or more, and a nitrogen content of 10 atomic % or less.
    Type: Application
    Filed: May 22, 2019
    Publication date: December 5, 2019
    Applicant: Shin-Etsu Chemical Co., Ltd.
    Inventors: Yukio INAZUKI, Kouhei SASAMOTO
  • Patent number: 10466583
    Abstract: A halftone phase shift mask blank comprising a transparent substrate and a halftone phase shift film thereon is provided. The halftone phase shift film includes at least one layer composed of a silicon base material having a transition metal content?3 at %, a Si+N+O content?90 at %, a Si content of 30-70 at %, a N+O content of 30-60 at %, and an O content?30 at %, and having a sheet resistance?1013/?/?. The halftone phase shift film undergoes minimal pattern size variation degradation upon exposure to sub-200 nm radiation, and has chemical resistance and improved processability.
    Type: Grant
    Filed: September 27, 2017
    Date of Patent: November 5, 2019
    Assignee: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Yukio Inazuki, Takuro Kosaka, Kouhei Sasamoto, Hideo Kaneko
  • Patent number: 10372030
    Abstract: A halftone phase shift mask blank is provided comprising a transparent substrate and a halftone phase shift film which is composed of a silicon base material having a Si+N+O content of at least 90 at %, a Si content of 30-70 at %, a N+O content of 30-60 at %, and an O content of up to 30 at %, and has a thickness of up to 70 nm. The halftone phase shift film is thin enough for mask pattern processing, undergoes minimal pattern size variation degradation upon exposure to sub-200 nm radiation, and maintains a necessary phase shift and transmittance.
    Type: Grant
    Filed: March 22, 2016
    Date of Patent: August 6, 2019
    Assignee: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Kouhei Sasamoto, Takuro Kosaka, Yukio Inazuki, Hideo Kaneko
  • Publication number: 20190146329
    Abstract: A photomask blank comprising a transparent substrate and a Cr-containing film is provided. The Cr-containing film includes a layer which is composed of a C-containing Cr compound and further contains 0 or 0 and N. The layer has a C/Cr atomic ratio of at least 0.3 and a N/Cr atomic ratio of up to 0.1, and has a Cr content of up to 50 at % and a C/O atomic ratio of at least 0.8, or a Cr content of up to 60 at % and a C/O atomic ratio of at least 1. The photomask blank is processed into a photomask by dry etching the Cr-containing film.
    Type: Application
    Filed: November 1, 2018
    Publication date: May 16, 2019
    Applicant: Shin-Etsu Chemical Co., Ltd.
    Inventors: Yukio INAZUKI, Kouhei SASAMOTO, Naoki MATSUHASHI
  • Publication number: 20180224737
    Abstract: A method for preparing a photomask blank comprising a transparent substrate and a chromium-containing film contiguous thereto involves the step of depositing the chromium-containing film by sputtering a metallic chromium target having an Ag content of up to 1 ppm. When a photomask prepared from the photomask blank is repeatedly used in patternwise exposure to ArF excimer laser radiation, the number of defects formed on the photomask is minimized.
    Type: Application
    Filed: January 30, 2018
    Publication date: August 9, 2018
    Applicant: Shin-Etsu Chemical Co., Ltd.
    Inventors: Yukio INAZUKI, Kouhei SASAMOTO, Tsutomu YURI
  • Patent number: 10040220
    Abstract: A hard mask film 2 provided on substrate 1 is formed by tin-containing chromium-containing material. In the chromium-containing material including tin, which forms the hard mask film 2, the etching resistance to fluorine-containing dry etching is equal to or higher than the etching resistance of the tin-free chromium-containing material, and it shows a significantly high etching rate as compared with a chromium-containing material free of tin under conditions for chlorine-containing dry etching. As a result, the time for chlorine-containing dry etching is shortened, and damage to a resist pattern is reduced. Thus, high-precision pattern transfer can be performed. The present invention provides a novel technique for increasing etching process-ability by increasing a dry-etching rate of a hard mask film made of a chromium-containing material while assuring a hard mask function of the hard mask film.
    Type: Grant
    Filed: August 12, 2016
    Date of Patent: August 7, 2018
    Assignee: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Souichi Fukaya, Hideo Nakagawa, Kouhei Sasamoto
  • Publication number: 20180088457
    Abstract: A halftone phase shift mask blank comprising a transparent substrate and a halftone phase shift film thereon is provided. The halftone phase shift film includes at least one layer composed of a silicon base material having a transition metal content?3 at %, a Si+N+O content?90 at %, a Si content of 30-70 at %, a N+O content of 30-60 at %, and an O content?30 at %, and having a sheet resistance?1013/?/?. The halftone phase shift film undergoes minimal pattern size variation degradation upon exposure to sub-200 nm radiation, and has chemical resistance and improved processability.
    Type: Application
    Filed: September 27, 2017
    Publication date: March 29, 2018
    Applicant: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Yukio INAZUKI, Takuro KOSAKA, Kouhei SASAMOTO, Hideo KANEKO
  • Patent number: 9880459
    Abstract: In a photomask blank comprising a transparent substrate, a resistance layer, and a conductive layer, the resistivity and thickness of the conductive layer and the resistivity and thickness of the resistance layer are selected so as to meet a specific equation (1). In EB lithography, a ground can be established at a necessary fully low resistance value, and EB writing be carried out at a high accuracy.
    Type: Grant
    Filed: July 11, 2016
    Date of Patent: January 30, 2018
    Assignee: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Kouhei Sasamoto, Souichi Fukaya, Yukio Inazuki
  • Patent number: 9864269
    Abstract: A photomask blank comprising a transparent substrate and a chromium-containing film is provided. The chromium-containing film is formed of a chromium compound containing Cr, N, and optionally O, has a total Cr+N+O content?93 at %, and meets the formula: 3Cr?2O+3N. A chromium compound layer meeting a first composition having a N/Cr atomic ratio?0.95, a Cr content ?40 at %, a Cr+N content?80 at %, and an O content?10 at % accounts for 10-70% of the overall thickness of the chromium-containing film.
    Type: Grant
    Filed: August 17, 2016
    Date of Patent: January 9, 2018
    Assignee: SHIN-ETSU CHEMICAL CO., LTD.
    Inventor: Kouhei Sasamoto