Patent ID: 7820369

Claim:
A process for patterning a substrate, comprising: (a) coating the substrate with a film of a photoresist composition comprised of (i) a polymer that is rendered soluble in aqueous base at a temperature of less than about 100° C. by acid-catalyzed deprotection of pendent acetal- or ketal-protected carboxylic acid groups, and (ii) a photoacid generator; (b) patternwise exposing the film to an imaging radiation source so as to form a latent, patterned image in the film; (c) baking the exposed film at a post-exposure bake temperature between about 25° C. and 80° C.; and (d) developing the latent image with a developer to form a patterned substrate, wherein the polymer is prepared by polymerization of a monomer mixture, the mixture comprising (a) at least one first olefinic monomer containing an acetal or ketal linkage, the acid-catalyzed cleavage of which renders the polymer soluble in aqueous base, and (b) at least one second olefinic monomer selected from (i) an olefinic monomer containing a pendant fluorinated hydroxyalkyl group R H , (ii) an olefinic monomer containing a pendant fluorinated alkylsulfonamide group R S , and (iii) combinations thereof, wherein R H has the formula -L 3 -CR 11 R 12 —OH, in which: L 3 is directly attached to an olefinic carbon, and is selected from C 1 -C 12 alkylene, substituted C 1 -C 12 alkylene, C 3 -C 15 alicyclic, C 3 -C 15 fluoroalicyclic, and combinations thereof; R 11 is selected from hydrogen, C 1 -C 24 alkyl, and substituted C 1 -C 24 alkyl; and R 12 is C 1 -C 24 alkyl or fluorinated C 1 -C 24 alkyl, provided that at least one of R 11 and R 12 is fluorinated, and further wherein R 11 and R 12 can be taken together to form a ring.