Patents by Inventor Hisamitsu Mitsutomi

Hisamitsu Mitsutomi 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).

  • Alignment marks on semiconductor wafers and method of manufacturing the marks
    Patent number: 4824254
    Abstract: Alignment marks on a semiconductor wafer comprise a first alignment island projecting from a surface of the wafer and a second alignment island having substantially the same height as the first alignment island and surrounding the same with a slit therebetween. The slit is utilized as a pattern for aligning with an alignment mark on a photomask. Preferably the alignment marks are formed on the grid line region of the wafer.
    Type: Grant
    Filed: May 18, 1984
    Date of Patent: April 25, 1989
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Hiroshi Ohtsuka, Yoshio Itoh, Tadashi Nishimuro, Hisamitsu Mitsutomi