Patents by Inventor Takesi Nagata

Takesi Nagata 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).

  • Bisphenol carboxylic acid tertiary ester derivatives and chemically amplified positive resist compositions
    Patent number: 5856561
    Abstract: Novel bisphenol carboxylic acid tertiary ester derivatives having two aromatic ether groups and an ester group which are all replaced by acid labile groups are provided. The derivatives are used as a dissolution inhibitor in a chemically amplified positive resist composition comprising an organic solvent, an alkali soluble resin, and a photo-acid generator. Since the dissolution inhibitor has a highly reactive acetal group as an acid labile group, its coupling-off rapidly takes place after exposure. The dissolution inhibitor itself is less alkali soluble and its acid decomposition product is a phenol derivative having a carboxylic acid group with high alkali solubility, leading to a high dissolution contrast.
    Type: Grant
    Filed: September 17, 1996
    Date of Patent: January 5, 1999
    Assignees: Shin-Etsu Chemical Co., Ltd., Nippon Telegraph and Telephone Corp.
    Inventors: Takesi Nagata, Satoshi Watanabe, Katsuya Takemura, Tsunehiro Nishi, Shigehiro Nagura, Akinobu Tanaka, Yoshio Kawai