Patents Represented by Law Firm Griffen, Butler, Whisenhunt & Szipl, LLP
  • Photosensitve polymide precursor and its use for pattern formation
    Patent number: 6025113
    Abstract: A polyimide precursor having repeating units of the formula: ##STR1## wherein R.sup.1 is a tetravalent organic group having 4 or more carbon atoms; R.sup.2 is a trivalent or tetravalent organic group having one or more aromatic rings; R.sup.3 is a monovalent organic group; A is a monovalent group showing acidity; and n is an integer of 1 or 2, is effective for preparing a highly sensitive negative-working photosensitive material developable with an alkaline aqueous solution in a short time with high resolution.
    Type: Grant
    Filed: June 16, 1997
    Date of Patent: February 15, 2000
    Assignee: Hitachi Chemical Company, Ltd.
    Inventors: Haruhiko Kikkawa, Fumio Kataoka, Issei Takemoto, Jun Tanaka, Keiko Isoda, Shunichiro Uchimura, Makoto Kaji, Minoru Sugiura