Raman microprobe study on temperature distribution during cw laser heating of silicon on sapphire

For the first time Raman microprobe experiments have been made to measure the space-resolved temperature distribution induced in silicon-on-sapphire by a stationary elliptical Gaussian laser beam. The algorithm [J. Appl. Phys. 57, 965 (1985)] for solving the nonlinear heat equation in a two-layer structure has been also extended to include the temperature dependence of laser power absorbed besides the temperature dependencies of thermal conductivity and diffusivity. The problems involved in applying the numerical calculations to the experimental situation are discussed. The numerical calculations of temperature distributions based on the present algorithm are found to give a good agreement with the present Raman microprobe results.