Reflectance-Correcting Pyrometry in Thin Film Deposition Applications

A detailed study of an emissivity-correcting pyrometer instrument for measuring wafer surface temperatures during thin film growth is presented. The basic physics is reviewed and preliminary data showing a temperature over-compensation artifact is shown. The rest of the report presents an exhaustive analysis of the potential sources for the temperature over-compensation effect. This analysis yields an in situ calibration method that can be used to remove temperature over-compensation artifacts that arise from any first-order systematic error in either the reflectance or thermal emission measurement. With corrections applied, artifact-free surface temperatures can be measured with a precision of a few {sup o}C over a wide range of wafer emissivities