Patents by Inventor Hironobu Sakuta

Hironobu Sakuta 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).

  • Flatness measuring apparatus
    Patent number: 6323952
    Abstract: A flatness measuring apparatus measures flatness of a substrate on which a specific pattern is to be formed by adjusting focus to a forming reference flat plane obtained based upon height data corresponding to specific measuring points of the substrate. The flatness measuring apparatus includes: an arithmetic operation device that obtains height data at predetermined measuring points of the substrate, determines a flatness judging criterion flat plane based upon height data at measuring points located at positions at which the specific measuring points are located through an arithmetic operation, determines quantities of displacement at the predetermined measuring points relative to the flatness judging criterion flat plane through an arithmetic operation, and measures the flatness of the substrate based upon the quantities of displacement.
    Type: Grant
    Filed: December 1, 1999
    Date of Patent: November 27, 2001
    Assignee: Nikon Corporation
    Inventors: Masahiko Yomoto, Hosei Nakahira, Eiji Matsukawa, Hironobu Sakuta