Material and process optimization for EUV pattern rectification by DSA

Continuous scaling by extreme ultraviolet (EUV) lithography is tightening the patterning requirements for photoresist materials. Specifically, chemically amplified resists (CAR) are facing significant challenges to keep supporting the patterning needs. In view of this, complementing EUV lithography with directed self-assembly (DSA) of block copolymers offers interesting opportunities to enable the use of CAR towards ultimate resolution. As DSA decouples the resist patterning performance from the final pattern quality, roughness and defects in the resist pattern can be rectified. Here, we discuss the impact of material and process parameters on the rectification performance by DSA, both for line-space and hexagonal contact hole arrays.