Implicit Enthalpy Method for Modelling Laser Induced Melting and Solidification of Silicon

摘要

This paper presents a numerical study of laser induced meltingand solidification of crystalline Silicon (Si) using an implicitenthalpy method. The simulations are performed using the opensource C++ solver known as OpenFOAM [1]. The modelconsiders temperature dependent thermo-physical and opticalproperties for Si. To verify the numerical model, its predictionsare compared with the experimental results for a nanosecondpulsed laser annealing of Si with pulse duration of 30 ns andwavelength (λ) of 308 nm. An excellent agreement with theexperimental results is observed for both the melting depth andthe melting duration. In the second part of this study, the KrFexcimer laser (λ = 248 nm) annealing of Si wafer widely used forproduction of solar cells is simulated. The effects of substrateheating on the melting duration, and re-crystallisation velocityare then investigated. Our results show that, for a given pulseduration, the maximum re-crystallisation velocity is almostindependent of the laser power but decreases with the substrateheating.