Time-dependent heat flow calculation of cw laser-induced melting of silicon

Abstract

The time evolution of the temperature profile during cw laser processing is calculated including the effects of melting using computer simulation. Results, presented for single-crystal silicon irradiated by an argon ion cw laser, show that high scanning speed can result in a non-steady-state situation for the temperature rise. In this case the maximum temperature and melt depth become functions of the dwell time and also less sensitive to the incident laser power, as a result of which scanning speed can be effectively used to control melting process induced by cw laser. Experimental results presented support the calculated dependence of the maximum melt depth on the laser power and scanning speed.