Temperature control system for wafer

摘要

Apparatus for processing a substrate (44) comprising; a susceptor (382) for supporting a substrate (44); an upper heat source (351) spaced above the susceptor; a lower heat source (352) spaced below the susceptor; and a controller (390) providing power to said heat sources at a selected ratio between said sources, said controller being configured to vary said ratio during a high temperature processing cycle of a substrate to thereby vary the ratio of the heat provided by the heat sources during the cycle. A method of maintaining uniform temperature of a semiconductor wafer during high temperature processing is also disclosed.