abstract |
An acid-labile ester monomer of spirocyclic structure has formula (1) wherein Z is a monovalent group having a polymerizable double bond, X is a divalent group which forms a cyclopentane, cyclohexane or norbornane ring, R 2 is H or monovalent hydrocarbon, R 3 and R 4 are H or monovalent hydrocarbon, or R 3 and R 4 , taken together, stand for a divalent group which forms a cyclopentane or cyclohexane ring, and n is 1 or 2. A polymer obtained from the acid-labile ester monomer has so high reactivity in acid-catalyzed elimination reaction that the polymer may be used to formulate a resist composition having high resolution. |