APPLICATION OF COMBINED EXPERIMENTAL AND NUMERICAL TECHNIQUES IN DETERMINING THE TEMPERATURE-DEPENDENCE OF REFLECTIVITY OF SEMICONDUCTORS

Combined experimental and numerical techniques for determining the tem perature dependence of reflectivity of basic semiconductors are analyz ed. The method for determination of the reflectivity dependence of liq uid semiconductors under pulsed laser irradiation on temperature devel oped earlier by the authors is modified for the case of solid semicond uctors. The results obtained by the time-resolved reflectivity measure ment technique together with the known temperature dependencies of the refraction index and the extinction coefficient for the cw probe lase r and the room-temperature data for the reflectivity at the frequency of the primary pulsed laser beam are the input parameters of this meth od. The method itself consists in matching the experimental and comput ed values of the maximum reflectivity of cw probe laser in dependence on the energy density of the laser pulse and a least-squares fitting p rocedure. The method is verified on experimental data for the XeCl exc imer laser irradiation of Si(100), giving R(s) = 0.590 +/- 0.005 + (4. 5 +/- 0.5) x 10(-5)(T-293) for the reflectivity of crystalline silicon , which is in good agreement with experimental measurements done by ot her investigators. In addition, numerical test and error analyses of b oth the method presented here and the previous method proposed for liq uid semiconductors are described and the accuracy and error limits of both methods are discussed.