Synthesis of a novel methacrylate, (1,4-dioxa-8-methacrylate amide spiro [4,5] decane) monomer and its co-polymerization with t-butyl-3 alpha-methacryloxy-7 alpha, 12 alpha-dihydroxy-5 beta cholan-24-oate for 193 nm photoresist

Abstract

A novel methacrylate-amide, 1,4-dioxa-8-methacrylate amide spiro [4,5]-decane has been synthesized by a simple method. The synthesized monomer and the polymers have been characterized by IR, H-1-NMR, C-13-NMR and GPC analysis. The novel monomer was used to copolymerize with t-butyl-3alpha-methacryloyloxy-7alpha, 12alpha-dihydroxy-5beta-cholan-24-oate [TBMC] for post exposure delay stability in 193-nm lithography. The copolymer has excellent transmittance at 193nm with respect to the homo-polymer, poly(TBMC) with 10 mole percentage of amide monomer. The lithography evaluation was carried out at a dose of 30 mJ/cm(2) using an ArF excimer laser stepper. A tetra-polymer with fluorine containing moiety has also been synthesized and used to enhance transparency.