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. 04, 2000
Filed:
Jan. 15, 1999
Shinichi Kono, Kanagawa-ken, JP;
Yasuo Masuda, Kanagawa-ken, JP;
Atsushi Sawano, Kanagawa-ken, JP;
Hayato Ohno, Kanagawa-ken, JP;
Hidekatsu Kohara, Kanagawa-ken, JP;
Toshimasa Nakayama, Kanagawa-ken, JP;
Tokyo Ohka Kogyo Co., Ltd., Kawasaki, JP;
Abstract
Phenolic compound (a) is polycondensed with mixed aldehyde (b) consisting essentially of 5-30 mol % of unsaturated aliphatic aldehyde (b-1) and 70-95 mol % of saturated aliphatic aldehyde (b-2) to give alkali-soluble novolak resin (A) as the product of polycondensation reaction. The alkali-soluble novolak resin (A) is used with quinonediazido group containing compound (B) to produce a positive photoresist composition. According to the present invention, there are specifically provided a positive photoresist composition that has high feature integrity in spite of high sensitivity and which yet provides a great depth of focus, a process for producing such positive photoresist composition, as well as an alkali-soluble novolak resin that can advantageously be used in such composition, and a method of forming patterns with high reproducibility using such positive photoresist composition.