Transmission-Based Temperature Measurement of a Workpiece in a Thermal Processing System

A thermal processing system for performing thermal processing of a semiconductor workpiece, the thermal processing system comprising:

• a workpiece support plate configured to support a workpiece;
• one or more heat sources configured to heat the workpiece;
• a window disposed between the workpiece support plate and the one or more heat sources, the window comprising one or more transparent regions that are transparent to at least a portion of electromagnetic radiation within a measurement wavelength range;
• and
• a temperature measurement system configured to obtain a temperature measurement indicative of a temperature of the workpiece based at least in part on one or more measurements from a plurality of infrared sensors when the temperature of the workpiece is less than about 600° C.

A method for determining a temperature of a workpiece in a thermal processing system, the thermal processing system comprising a workpiece support plate configured to support a workpiece;

• one or more heat sources configured to heat the workpiece;
• a window disposed between the workpiece support plate and the one or more heat sources, the window comprising one or more transparent regions that are transparent to at least a portion of electromagnetic radiation within a measurement wavelength range;
• a temperature measurement system comprising an emissivity measurement system and a transmittance measurement system, the method comprising:
• obtaining, from a plurality of infrared sensors, one or more measurements associated with the transmittance measurement system;
• and
• determining, based at least in part on the one or more measurements associated with the transmittance measurement system, a temperature of the workpiece when the temperature of the workpiece is less than about 600° C.