3-DIMENSIONAL THEORY TO STUDY PHOTOTHERMAL PHENOMENA OF SEMICONDUCTORS .1. MODULATED OPTICAL REFLECTANCE

A thorough theoretical study of the modulated optical reflectance (MOR) response of semiconductor samples has been presented. The three-dimensional plasma and thermal equations are solved analytically, and then numerical calculations are given for the high-frequency MOR signal. The influences of the optical, thermal, and electronic parameters on the MOR signal are discussed in detail. The generation mechanisms of the MOR signal will be clarified. On the other hand, the mathematical analyses also provide a quantitative tool by which one can fit the theoretical curves to experimental data to determine several material parameters, such as the surface recombination velocity, the lifetime of photogenerated carriers, and thermal conductivity of the materials.