Abstract: A method for preparing a chamber prior to semiconductor processing includes the step of flowing a non-reactive gas, preferably argon, through the chamber at a pressure below 4 Torr to sweep contaminants from the chamber. The chamber pressure is reduced to less than 1 Torr prior to sweeping with argon, and the sweeping cycle is repeated as needed to remove contaminants. The chamber is heated during subsequent sweep cycles to enhance removal of contaminants. Following the sweep cycles, remaining contaminants are baked out at a chamber pressure less than 6.0×10−6 Torr. The method substantially bakes out moisture and other contaminants from the chambers in less than 8 hours, and prepares the chamber for processing in less than one day.