Photoresist composition for deep ultraviolet lithography

A process for imaging a photoresist composition comprising the steps of:

• a) forming on a substrate a photoresist coating from a photoresist composition;
• b) image-wise exposing the photoresist coating;
• c) postexposure baking the photoresist coating;
• and
• d) developing the photoresist coating with an aqueous alkaline solution;
• and,
• where the photoresist composition comprises a photoacid generator and a fluorinated polymer, where the fluorinated polymer is a reaction product of polymer containing an aliphatic monocyclic fluoroalcohol unit with at least one compound capable of functionalizing the fluoroalcohol unit with an alkyloxycarbonylalkyl group of structure—(CR3R4)p(CO)OR5, where R3 and R4 are independently H, F, (C1-C8)alkyl, (C1-C8)fluoroalkyl, cycloalkyl, cyclofluoroalkyl, (CR3R4)p(CO)OR5, R3 and R4 may combine to form an alkyispirocyclic or a fluoroalkylspirocyclic group, R5 is H or an acid labile group, and p=1-4 further where the polymer containing the monocyclic fluoroalcohol unit is selected from at least one of structures I to VIII,
• where Rf is a fluoroalkyl group (C1-C8),
• Ra, Rb, Rc, Re, Rg and Rh are independently alkyl and fluoroalkyl, and Ra-Re and Rg can independently be substituted with alkyl, fluoroalkyl, spirofluoroalkyl or spiroalkyl substituent, where at least one of Ra, Rb, Rc and Rd is a fluoroalkyl group,
• Y is independently alkyl or fluoroalkyl spacer group (C1-C8), and
• X is independently CF2 or O.