Patents by Inventor Hiroaki Soma

Hiroaki Soma 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: 6104481
    Abstract: A wafer surface inspection apparatus comprises a light source, an optical system for focusing the light beams from the light source onto the wafer surface, a scanning means for scanning the focused point over a predetermined range on the wafer surface, a photo detector including an photoelectric converter for sensing scattered light from the focused point, and a signal detector for detecting signals from the photo detector, in which the light source is a light source for emitting two different wavelengths, the optical system is adapted to focus the light beams of the two wavelengths on one and the same point on the wafer surface, and the photo detector is adapted to sense the two wavelengths separately, and further comprises a discriminating portion for discriminating between a foreign matter or a scratch on the wafer surface and a recess in a spot form existing on the wafer surface by utilizing outputs from the signal detector.
    Type: Grant
    Filed: November 2, 1998
    Date of Patent: August 15, 2000
    Assignee: Kabushiki Kaisha Topcon
    Inventors: Akihiko Sekine, Yoichiro Iwa, Hiroaki Soma, Naoto Miki, Hisashi Isozaki, Hisakazu Yoshino