Contactless measurement of surface temperature and surface potential of Si by photoreflectance spectroscopy

Surface temperature and surface potential of Si wafers have been measured by photoreflectance (PR) spectroscopy. The surface temperature was obtained in the range from 25° C to 134° C within the error of ±0.6° C from transition energy which was calculated from the PR spectrum by the 3-point method based on 3rd derivative theory. spatial distribution of surface temperature was also measured successfully in a Si wafer heated partially. Surface potential was estimated by comparison of experimental PR spectral intensity with theoretical values, taking into account photoinduced change of the surface field. The results show that the surface potential of Si wafers varies with temperature in the atmosphere.