Pattern collapse in the top surface imaging process after dry development

In this article the pattern collapse in a 193 nm top surface imaging proces s after dry development is described. We dry developed the resist with O-2 and SO2 plasmas at low temperature in order to replicate a fine pattern pro file. Pattern collapse occurred because of stress from neighboring patterns when SO2 was added at low substrate temperatures and the line/space binary pattern was below 0.15 mu m. We found, using Auger electron spectroscopy a nalysis, that a sulfuric compound covered the side walls of the pattern whe n SO, was used. We propose a pattern collapsing mechanism caused by the rea ction of H2O with the evaporation of water adsorbed by the sulfuric compoun d on the resist pattern. It is therefore effective to decrease the sulfuric compound on the patterns before the wafer is removed from the etching cham ber. Finally, we successfully replicated a sub-0.10 mu m line and space pat tern without pattern collapse. (C) 1998 American Vacuum Society. [S0734-211 X(98)16306-0].