High-performance 157 nm resist based on fluorine-containing polymer

Abstract

A new high-performance resist for F/sub 2/ laser (157 nm) VUV (vacuum ultraviolet) lithography has been developed. The resist polymers consist of fluorinated-alicyclic methacrylate (MA), fluorinated-alkyl MA, acid labile unit, etch-resistant unit and adhesive unit. These polymers can be easily synthesized at low cost. A resist based on this polymer has over 40% transmittance per 100 nm thickness and the same etch-resistance as adamanthyl MA type-ArF resists. Fine images with vertical profiles of 200 nm thickness are obtained by contact exposure with the F/sub 2/ laser. Simulations showed that the resolution of this resist with a F/sub 2/ laser stepper (NA 0.85) has 70 nm L/S and 40 nm isolated line pattern capability at 200 nm thickness. Based on the developed 157 nm resist, 157 nm VUV lithography can be accepted as a 70 nm node.