The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 14, 1989
Filed:
Jun. 16, 1987
Shingo Asaumi, Fujisawa, JP;
Hidekatsu Kohara, Chigasaki, JP;
Hatsuyuki Tanaka, Samakawa, JP;
Toshimasa Nakayama, Hiratsuka, JP;
Tokyo Ohka Kogyo Co., Ltd., Kanagawa, JP;
Abstract
Although the positive-working photoresist composition comprises a phenolic novolac resin as the film-forming component and a known photosensitizing compound as in conventional compositions, the novolac resin is prepared from a specific mixture of two classes of phenolic compounds including, one, phenol, cresols and/or resorcinol and, the other, one or more of the phenolic compounds having a nucleus-substituting group selected from allyloxy, allyloxymethyl, allyl dimethyl silyl, 2-(allyl dimethyl silyl) ethoxy, cinnamoyl, acryloyl and methacryloyl groups. By virtue of this unique combination to give the phenolic moiety in the novolac resin, the photoresist composition has markedly improved heat resistance as well as stability against plasma in dry etching so that the composition can give a patterned photoresist layer with extreme fineness having high fidelity to the mask pattern.