During fabrication, a rotating semiconductor substrate is radiated in accordance with a thermal recipe. Temperature measurements of the semiconductor substrate are obtained along with the position of the semiconductor substrate at the time of each temperature measurement. It is then determined for the position of the semiconductor substrate whether at least one particular temperature measurement of the temperature measurements should be filtered. If so, at least one filtered temperature measurement is obtained. The radiation of the semiconductor substrate is subsequently controlled based on the temperature measurements, the at least one filtered temperature measurement, and the thermal recipe.