Temperature Measurement by Thermoreflectance at Near Grazing Angles Available to Purchase

An ellipsometric method has been developed that utilizes a thermoreflectance technique to measure the differential reflectance from a polarization modulated laser beam at near grazing probe angles. The technique is investigated here as a potential method for monitoring small changes in temperature about a control point on closely stacked silicon wafers in a heated furnace during batch processing. The technique is demonstrated on both polished and unpolished wafers with a temperature resolution of ∼0.5°C. Temperature measurement and sensitivity is investigated for furnace temperatures ranging from 20°C to 1000°C.