Effects of polymer structure on dissolution characteristics in chemically amplified 193-nm resists

Abstract

This paper describes the effects of the blocking level of polymer on both dissolution characteristics and lithographic performance in chemically amplified positive 193 nm resists consisting of a alicyclic methacrylate polymer and a photoacid generator. There were clear relationships between the blocking level and both the dissolution rate characteristics and the lithographic performance. We found that the dissolution contracts and developer selectivity improved as the blocking level of polymer increased, and then the resolution capability was improved. However, the dry-etch resistance and adhesion property of the resist film deteriorated as the blocking level increased, although these were at the same levels as those of conventional i-line novolak resist or polyhydroxystyrene base KrF resists. Therefore, these resist materials show potential for the next generation of LSI devices. Ideal dissolution parameters for improving the resolution capability were obtained by using a resist profile simulator. By using a high-contrast resist incorporating these parameters, and by using a higher numerical aperture lens and annular illumination, the mass production of next-generation devices with a 0.12 micrometers design rule can be achieved.