Raman microprobe analysis of temperature profiles in CW laser heated silicon microstructures

Steady-state laser heating of silicon disk microstructure on focused silica and sapphire is examined using the 4880 and 5145 Å lines from an argon-ion laser to heat the disk at the center and to probe it with submicrometer spatial resolution. The Stokes shift and line broadening of the Raman microprobe spectra are compared to simulations of the Raman spectra, which utilize temperature profiles calculated by a finite-difference analysis of the heat flow equation. The Raman simulation model incorporates the effects of temperature inhomogeneities, strain, and photon-created free carriers within the probed volume; temperature nonuniformity is found to be the most important factor and to be quite significant.