Abstract
A new simple method was developed to estimate the diffusion range of photogenerated acid in chemical amplification resist systems. The acid mobility was investigated for various process conditions. It was found that prebake and post-exposure-bake conditions have strong influence on the mobility of acid. The diffusion range of acid is much larger than values estimated from the catalytic volume. No acid diffusion could be detected at room temperature over a period of 2 days. Acid from an onium salt acid generator showed a stronger diffusion than acid from a methanesulfonic acid ester.
