Supercooling of Silicon and Germanium after Laser Melting

摘要

Following pulsed laser melting, supercoolings of 505 deg K in Si and 430 deg K in Ge were observed prior to bulk nucleation. These large supercoolings are obtained because of the extremely high thermal quench which follows laser irradiation. Nucleation rates were estimated to be approx.10 sup 29 events/m sup 3 /s. Assuming that homogeneous nucleation was achieved, surface energies are estimated to be 0.34 J/m sup 2 for Si and 0.24 J/m sup 2 for Ge. These results are in reasonable agreement with traditional homogeneous nucleation experiments sensitive to rates of only approx.10 sup 10 events/m sup 3 /s. This laser melting technique is applicable to nucleation studies in a wide variety of materials. 21 refs., 3 figs. (ERA citation 13:015090)