Abstract:
This is a new N-tert-butoxycarbonylmaleimide (t-BOCMI) of formula (I) . The method comprises (A) reacting maleimide and furan and forming 3,6-epoxy- 1,2,3,6-tetrahydrophthalimide by Diels - Alder reaction; (B) making N-(t-butoxycarbonyl)3,6-epoxy- 1,2,3,6- tetrahydrophthalimide by reacting (A) and di-t- butyldicarbonate; and (C) heating and decomposing (B) in toluen and getting final product of (I). Total process yield is 87% and melting pt. of the product is 62 deg.C. The product is identified by IR, C13 and H1 NMR, MS, GC/MS, and component analysis. The above t-BOCMI is a very good resist material.
Abstract:
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.