Study on modeling of resist heating effect correction in multi-beam mask writers

Strict specifications of local critical dimension uniformity (LCDU) and line edge roughness (LER) on the leading-edge mask fabrication encourage wide use of the lower sensitivity resist for electron beam lithography. This is because the higher exposure dose for the patterning reduces the shot noise effect, which is the statistical position variability of electrons produced by the beam shots. As the exposure dose increases the resist heating effect started to be seen in the multi-beam mask (MBM) writers as well as the single variable-shaped beam (S-VSB) mask writers. The resist heating effect is a phenomenon where resist sensitivity changes depending on the substrate temperature rise. This results in degradation of LCDU. This report deal with the behavior of resist heating effect in MBM, and modeling for correction.