Microlithographic Assessment of a Novel Family of Transparent and Etch-Resistant Chemically Amplified 193-nm Resists Based on Cyclopolymers

The evaluation and structural optimization of a family of single layer, positive tone, chemically amplified resists for 193-nm lithography is presented. The resists are formulated from cyclopolymeric materials in which the nature, etch properties, and spatial disposition of the substituents are systematically varied. Their lithographic performance is evaluated on the basis of the interplay between chemical structure, molecular weight, and comonomer composition. These materials have good optical clarity at the desired wavelength, excellent resolution to ca. 90 nm with a phase-shifting mask, and outstanding reactive ion etch resistance.