Fast gas exchange for thermal conductivity modulation

摘要

A method for thermally processing a semiconductor substrate comprises: heating the substrate to a target peak temperature while controlling the gas pressure in the processing chamber at a pressure level that is significantly lower than atmospheric pressure; providing a flow of a purge gas between the substrate and a thermal reservoir at or near the time the substrate temperature reaches the target peak temperature while adjusting the gas pressure in the processing chamber to a second pressure level. Preferably, the purge gas has a relatively high thermal conductivity.