EUV underlayer materials for 22nm HP and beyond

Abstract

EUV lithography is expected to be an important technology for manufacturing 22 nm node and beyond in the semiconductor industry. To achieve the desired resist RLS performance for such fine feature patterns, multilayer materials are almost certainly needed to define the overall lithography process. The resist modeling and experiment studies suggest high EUV absorbance of the film improves resolution, line width roughness and sensitivity. In this paper, we report the studies of new EUV underlayers (EBL) based on crosslinkable organic underlayer materials with high EUV photon absorption (EPA) unit. The lithography results for the new EUV underlayer materials have demonstrated advantages over conventional organic underlayer in terms of resist sensitivity, resolution, process window, pattern profile, collapse margin, and possibly line width roughness.