Ramping susceptor-wafer temperature using a single temperature input

摘要

A method and apparatus for uniformly ramping the temperatures of a wafer and a susceptor using a first heat source primarily directed at the wafer and a second heat source primarily directed at the susceptor while keeping the wafer at approximately the same temperature as the susceptor but measuring only the temperature of the susceptor. The method comprises the steps of: determining and storing a plurality of steady-state temperatures of the susceptor as a function of the total power provided to the first heat source and the second heat source; ramping the susceptor from an initial temperature to a final temperature; and heating the wafer from the initial temperature to the final temperature, wherein the power to the first heat source is determined from the susceptor's temperature and the plurality of steady-state temperatures of the wafer and susceptor as a function of total power.