Chemically amplified resist is produced on the basis of vinyl polymer having 3-oxo-4-oxabicyclo[3.2.1]otane-2-yl group expressed by general formula (1) where each of L1, L2, L3, L4, L5 and L6 is selected from the group consisting of hydrogen atom and alkyl groups having the carbon number from 1 to 8, and the hydrogen atom and/or the alkyl group at L5 and L6 are replaced with alkylene groups having the carbon number from 1 to 10 and bonded to each other for forming a ring so that the resist exhibits high transparency to light equal to or less than 220 nm wavelength, large resistance against dry etching and good adhesion to substrates.