Novel alkaline-soluble alicyclic polymer poly(TCDMACOOH) for ArF chemically amplified positive resists

We have developed a novel ArF resist polymer poly(carboxy-tricyclo[5.3.2.0(2,6)]decanylmethyl methacrylate) (poly(TCDMACOOH)), which has a carboxyl substituent on the tricyclodecanyl group. This polymer exhibited good solubility (1.93 mu m/sec) in a 2.38% TMAH solution, high transparency (70 %/mu m) at 193 nm, and a good dry-etching resistance for CF4 gas (1.2 times the etching rate of novolac resin). Furthermore, the resist composed of the partially protected copolymer poly(TCDMACOOH(60)-TCDMACOOtBu(40)) with a photoacid generator exhibits a resolution of 0.18 mu m L/S using an ArF exposure system (NA=0.55).