| abstract |
A polymer comprises the polymerized product of monomers comprising an acid-deprotectable monomer, a base-soluble monomer, a lactone-containing monomer, and a photoacid-generating monomer; a chain transfer agent of the formula; n n n n n n n n n n wherein Z is a y valent C 1-20 organic group, x is 0 or 1, R d is a substituted or unsubstituted C 1-20 alkyl, C 3-20 cycloalkyl, C 6-20 aryl, or C 7-20 aralkyl; and optionally, an initiator. |