Patent ID: 7300558
Filing Date: 2007-11-27
Classification: C23C

Abstract:
1. An apparatus comprising: (a) a chamber defining an interior space adapted to be maintained at a reduced pressure; and (b) a gas supply means for supplying at least one burst of gas to said chamber for rapidly establishing at least one preselected gas pressure in said chamber, said gas supply means including: said gas supply means is adapted for sequentially supplying a plurality of different bursts of gas to said chamber for rapidly establishing a respective plurality of preselected gas pressures in said chamber, said gas supply means including a plurality of burst ballasts fluidly connected to said supply ballast via respective metering valves, and a corresponding plurality of on/off valves fluidly connected to respective ones of said plurality of burst ballasts and said chamber for supplying said process chamber with said gas from a selected one of said plurality of burst ballasts.