Simulation research on FIB processing: A comparison between silicon and diamond

The interactions between energetic gallium ion with silicon and diamond have been studied using Large-Scale Molecular Dynamics simulation method. In order to reveal the dependence of implantation depth and damage upon the beam voltage, a serial of simulations have been performed under impact energy of 2, 5, 8, 12, and 16 kev respectively for the Ga ions. The results indicate that both the normalized implantation depth D and the peak temperature (T_max) during the collision process are increased with the increase of the impact beam voltage. With the same lattice crystal structure and collision energy, the silicon contains a higher T_max and a smaller D compared with diamond under all impact energy tested. Further damage evolution analysis and lattice structure changes reflected by radius distribution function (RDF) indicate that the damage of silicon caused by ion bombardment is worse than diamond, which is mainly related to the higher collision temperature and lateral recrystallization process.