Etching Mechanisms of CF₃ Etching Fluorinated Si: Molecular Dynamics Simulation

Molecular dynamics simulations are performed to investigate CF3 continuously bombarding the amorphous silicon surface with energies of 10, 50, 100 and 150 eV at normal incidence and room temperature. The improved Tersoff-Brenner potentials were used. The simulation results show that the steady-state etching rates are about 0.019, 0.085 and 0.1701 for 50, 100 eV and 150eV, respectively. With increasing incident energy, a transition from C-rich surface to F-rich surface is observed. In the region modified by CF₃, SiF and CF species are dominant.