Problem drytek2 2004-01-27 18:35:20: Photoresist etches very fast in nitride recipe

[yiching at snf.stanford.edu]

Using the standard nitride recipe (SF6=53, F13=33), 3612 photoresist etches faster than nitride. Published etched rate is 450A/min, actual etch rate is > 700A/min. 2um resist is gone in less than 30min. Nitride etch rate seems right.