Low abosorbing resists for 157 nm lithography

摘要

The present invention provides photoresist materials for use in photolithography at wavelengths less than about 248 nm. More particularly, the photoresists of the invention are particularly suited for use in 157 nm lithography. A photoresist composition of the invention includes a polymer having at least one monomeric unit having an aromatic moiety. The monomeric unit further includes at least a group, such as an electron withdrawing group, attached to the aromatic moiety. The attached group includes at least one CF bond. The polymer further includes an acidic hydroxyl group. A photoresist composition of the invention can have an absorbance in a range of 1-5 mum<-1 >at 157 nm, rendering it particularly suitable for use as a single layer resist in 157 nm lithography.