PRODUCTION OF N-T-BUTOXYCARBONYLMALEIMIDE (CO)POLYMER, AND METHOD FOR FORMING HEAT-RESISTANT POSITIVE RESIST IMAGE USING N-T-BUTOXYCARBONYLMALEIMIDE (CO)POLYMER

摘要

The copolymer, useful for a heat-resistant positive resist image, of N-t-butoxycarbonyl maleimide and styrene deriv. is produced by radical polycondensing an N-t-butoxycarbonyl maleimide monomer and a styrene deriv. with a radical initiator. The styrene deriv. is pref. styrene, p-acetoxystyrene, p-methylstyrene, p-t-butoxycarbonyloxystyrene, p-trimethylsillylstyrene or p- chlorinated styrene. The resist image is formed by spin-coating a soln. obtd. by dissolving the copolymer and an onium salt in a chlorobenzene on the silicon wafer, prebaking, ultra-violet exposing and postbaking the coated wafer, and developing it with a developing liquor i.e. trimethylammonium hydroxy soln., anisole, toluene, methylisobutyl ketone or chloroform.