Experimental validation of full-field extreme ultraviolet lithography flare and shadowing corrections

Abstract

Extreme ultraviolet lithography (EUVL) is the leading candidate for 22nm half-pitch device manufacturing. IMEC has a fully integrated 300mm EUVL process line incorporating an Alpha Demo Tool (ADT) from ASML, aimed to understand issues related to the introduction of EUV technology in high-volume manufacturing. This study experimentally investigates flare and shadowing correction strategies. Experimental characterization of the flare of the ADT is reported, as well as experimental rules for flare variation correction. With respect to shadowing, shadowing corrections are experimentally estimated. Comparisons of experimental data and rigorous simulation are also presented, and a computationally efficient methodology to generate a full-chip flare map is proposed.