Gd. Ivlev et Ei. Gatskevich, TEMPERATURE-INDUCED CHANGES IN OPTICAL-PROPERTIES OF THE LIQUID-PHASEDURING NANOSECOND LASER MELTING OF SILICON AND GERMANIUM, Semiconductors, 30(11), 1996, pp. 1093-1098
Complex refractive indices of liquid silicon and germanium in the temp
erature ranges of thermodynamic stability of the liquid state have bee
n calculated by two methods, by structure factor modeling and using th
e specific electrical conductivities of the melts. Time-resolved refle
ctivity of the liquid phase formed by nanosecond ruby laser heating of
semiconductors has been studied using probe radiation at wavelengths
of 0.53 or 1.06 mu m and optical pyrometry has been used to determine
the peak temperature as a function of the radiation energy density. Th
e calculated data based on structure factor modeling agree better with
experiment for germanium than for silicon. The experimental data indi
cate that significant overheating, by several hundred degrees, of the
liquid phase by nanosecond laser melting of diamond-like semiconductor
s is quite feasible. (C) 1996 American Institute of Physics.