Abstract: A method of measuring temperature across wafers during semiconductor processing includes the step of providing a correlation between a peak wafer temperature during a processing step and a change in wafer surface charge or surface potential following the processing step. A first wafer to be characterized for its peak temperature spatial distribution during the processing step is processed through the processing step. The wafer surface charge or surface potential at a plurality of locations on the first wafer are measured following the processing step. A peak temperature spatial distribution for the first wafer is then determined based on the correlation and the wafer surface charge or surface potential measured in the measuring step.