Zero-shrink dimension evaluated for ArF-resist patterns measured by CD-SEM

Resist patterns for ArF-laser lithography slim by electron radiation in Critical Dimension-Scanning Electron Microscope (CD-SEM). To estimate initial CD that includes no LWS, the CD at 0th measurement was extrapolated from shrink-curve that indicates the slimming. Invisible slimming, occurring between the 0th and 1st measurement, was estimated. We made software for CD-SEM to calculate the 0th-CD. Estimation error in the extrapolated 0th-CD was estimated less than 0.9 nm, and the overall slimming including the invisible shrink was 0.3 nm in line-shaped patterns.