Patents by Inventor Keishi TSUKIYAMA

Keishi TSUKIYAMA 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).

  • Reflective mask blank for EUV lithography, reflective mask for EUV lithography, and method for manufacturing same
    Patent number: 11953822
    Abstract: The present invention relates to a reflective mask blank for EUV lithography, including: a substrate, a multilayer reflective film reflecting EUV light, and a phase shift film shifting a phase of the EUV light, in which the substrate, the multilayer reflective film, and the phase shift film are formed in this order, the phase shift film includes a layer 1 including ruthenium (Ru) and nitrogen (N), and the layer 1 has an absolute value of a film stress of 1,000 MPa or less.
    Type: Grant
    Filed: May 18, 2023
    Date of Patent: April 9, 2024
    Assignee: AGC INC.
    Inventors: Hirotomo Kawahara, Daijiro Akagi, Hiroaki Iwaoka, Toshiyuki Uno, Michinori Suehara, Keishi Tsukiyama
  • REFLECTIVE MASK BLANK FOR EUV LITHOGRAPHY, REFLECTIVE MASK FOR EUV LITHOGRAPHY, AND METHOD FOR MANUFACTURING SAME
    Publication number: 20230324785
    Abstract: The present invention relates to a reflective mask blank for EUV lithography, including: a substrate, a multilayer reflective film reflecting EUV light, and a phase shift film shifting a phase of the EUV light, in which the substrate, the multilayer reflective film, and the phase shift film are formed in this order, the phase shift film includes a layer 1 including ruthenium (Ru) and nitrogen (N), and the layer 1 has an absolute value of a film stress of 1,000 MPa or less.
    Type: Application
    Filed: May 18, 2023
    Publication date: October 12, 2023
    Applicant: AGC INC.
    Inventors: Hirotomo KAWAHARA, Daijiro AKAGI, Hiroaki IWAOKA, Toshiyuki UNO, Michinori SUEHARA, Keishi TSUKIYAMA