US Patent 7358175 Serial thermal processor arrangement

A serial thermal processing arrangement for treating a wafer of semiconductor material, the steps including: loading the wafer into a chamber at an initial station and purging the chamber with nitrogen gas; introducing formic acid vapor and nitrogen and heating the wafer at ambient; introducing a vacuum and heat onto the wafer; introducing formic acid vapor and nitrogen, heating the wafer at ambient; introducing nitrogen gas, and cooling the wafer at ambient; and lastly, unloading the wafer from its chamber.