Litho tool explores tradeoffs at 20nm and below

摘要

[Aki Fujimura] explained how accuracy inherent in mask writers is impacted at 20nm and below. "For mask writing, which is based on 50keV e-beams, discontinuity occurs below 80nm sizes," he said. Above 80nm mask dimensions, one could count on the shot size being faithfully reproduced on the mask surface, he noted; going below 80nm, however, one is no longer is able to get the same shape nor will the size be reproduced every time, nor will the printed feature be reliable in size.