Patent ID: 8999630
Filing Date: 2015-04-07
Classification: G03F

Abstract:
1. A pattern forming process comprising the steps of: applying a resist composition onto a substrate, the resist composition comprising a polymer comprising recurring units of at least one type having a hydroxyl group substituted with an acid labile group selected from recurring units (a1) or (a5) of the general formulae (1) or (5), an acid generator, and an organic solvent or comprising a polymer comprising recurring units of at least one type having a hydroxyl group substituted with an acid labile group selected from recurring units (a1) or (a5) of the general formulae (1) or (5) and recurring units of at least one type selected from recurring units of the general formulae (e1) to (e3) and an organic solvent, prebaking the composition to form a resist film, exposing the resist film to high-energy radiation, baking, and developing the exposed film in an organic solvent-based developer to form a negative pattern wherein the unexposed region of film is dissolved away and the exposed region of film is not dissolved, wherein R 1 and R 18 each are hydrogen or methyl, R 2 and R 19 each are a single bond or a straight, branched or cyclic C 1 -C 6 alkylene group which may contain an ether or ester radical, and R 3 and R 20 each are an acid labile group, wherein R 24 and R 28 each are hydrogen or methyl, R 21 is a single bond, phenylene, —O—R 33 , or —C(═O)—Y—R 33 , Y is oxygen or NH, R 33 is a straight, branched or cyclic C 1 -C 6 alkylene group, alkenylene or phenylene group, which may contain a carbonyl (—CO—), ester (—COO—), ether (—O—) or hydroxyl radical, R 22 , R 23 , R 25 , R 26 , R 27 , R 29 , R 30 , and R 31 are each independently a straight, branched or cyclic C 1 -C 12 alkyl group which may contain a carbonyl, ester or ether radical, or a C 6 -C 12 aryl, C 7 -C 20 aralkyl, or thiophenyl group, Z 0 is a single bond, methylene, ethylene, phenylene, fluorophenylene, —O—R 32 —, or —C(═O)—Z 1 —R 32 —, Z 1 is oxygen or NH, R 32 is a straight, branched or cyclic C 1 -C 6 alkylene group, alkenylene or phenylene group, which may contain a carbonyl, ester, ether or hydroxyl radical, M − is a non-nucleophilic counter ion, e1, e2 and e3 are in the range: 0≦e1≦0.3, 0≦e2≦0.3, 0≦e3≦0.3, and 0<e1+e2+e3≦0.3.