EUV resist imaging below 50 nm using coherent spatial filtering techniques

Lithography results using spatially-filtered coherent EUV radiation are presented. These experiments were done using a new 10× Schwarzschild optic and other significant upgrades for high stability and throughput of the system. Included are both single- and multiple-pitch images. A chemically-amplified EUV resist is shown performing at dense 50-nm linewidths and loose 25-nm features. High resolution polymers (HSQ and PMMA) were also tested and demonstrate dense 40-nm linewidths, which are the smallest 1:1 multi-pitch features attempted at this time.