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:
Jul. 18, 1995
Filed:
Nov. 17, 1993
Taku Nakao, Kanagawa, JP;
Remi Numata, Kanagawa, JP;
Kousuke Doi, Kanagawa, JP;
Nobuo Tokutake, Kanagawa, JP;
Hidekatsu Kohara, Kanagawa, JP;
Toshimasa Nakayama, Kanagawa, JP;
Tokyo Ohka Kogyo Co., Ltd., , JP;
Abstract
Disclosed is a positive-working photoresist composition suitable for use in the photolithographic fine patterning work in the manufacture of electronic devices such as VLSIs. The composition comprises, in addition to an alkali-soluble novolac resin as a film-forming ingredient and an esterification product of naphthoquinone-1,2-diazide sulfonic acid as a photosensitive ingredient, a unique additive compound which is an alkyl or aralkyl ester of 2-hydroxy benzoic acid, such as benzyl salicylate, or a phenol compound substituted at least one alkyl group such as 2-tert-butyl-4-methyl phenol. By virtue of the addition of this unique additive, the inventive photoresist composition exhibits an excellent performance of suppressing the standing wave effect in addition to the excellent photosensitivity, resolving power and depth of focusing in the patterning exposure to light as well as good heat resistance of the patterned resist layer.