| abstract |
A copolymer include repeat units derived from an acid-labile monomer, an aliphatic lactone-containing monomer, a C 1-12 alkyl (meth)acrylate in which the C 1-12 alkyl group includes a specific base-soluble group, a photoacid-generating monomer that includes an aliphatic anion, and a neutral aromatic monomer having the formula n n n n n n n n n n wherein R 1 , R 2 , R 3 , X, m, and R 5 are defined herein. The copolymer is used as a component of a photoresist composition. A coated substrate including a layer of the photoresist composition, and a method of forming an electronic device using the coated substrate are described. |