Patents by Inventor Yoshio Yamashima

Yoshio Yamashima 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).

  • Negative resist material
    Patent number: 4826943
    Abstract: A negative resist material consists of poly (silsesquioxane) of weight average molecular weight 2000 or more represented by the general formula (1):(CH.sub.2 .dbd.CHCH.sub.2 SiO.sub.3/2).sub.m (ClCH.sub.2 SiO.sub.3/2).sub.n (1)where m and n denote the molar percentages of each component of the polymer, and m+n=100. A method of producing such a resist material and a method of forming a bi-layer resist pattern using the resist material are also disclosed.
    Type: Grant
    Filed: July 27, 1987
    Date of Patent: May 2, 1989
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Toshio Ito, Miwa Sakata, Yoshio Yamashima