摘要

Laser recrystallization technology provides an effective way to fabricate high quality single crystalline germanium (Ge) on sapphire. In this work, a thermal physics model of continuous wave (CW) laser irradiation of SiO2/Ge/Sapphire epitaxial films is established and the temperature distribution of the whole system is discussed to better understand this process. Optical parameters such as reflectivity, transmissivity, and absorption rate of the studied thin films irradiated by 808 nm continuous wave laser are studied by finite-difference time-domain (FDTD) simulation. We have evaluated the temperature profile of the SiO2/Ge/Sapphire epitaxial films using a finite element simulation based on solving the general heat equation using COMSOL Multiphysics. Some main process parameters such as the laser power, the initial temperature and the effective beam radius have been varied to precisely control the temperature distribution of the epitaxial films and to optimize the process. The obtained results of our study will provide theoretical guidance for the fabrication of high quality single crystalline Ge on sapphire by laser recrystallization technology.

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