Spatial Energy Distributions of Sputtered Atoms and Reflected Particles during Kr+ and Ar+ Ion Beam Sputtering of Si and Ge

For the successful low temperature growth of Si and Ge thin films using ion-beam sputter deposition (IBSD), it is important to avoid residual damage induced by energetic sputtered atoms and/or reflected particles and the incorporation of reflected particles into growing films. We have used a Monte Carlo program to calculate the spatial flux and energy distributions of sputtered atoms and reflected particles as a function of ion beam incidence energy, incidence angle, and energy for different combinations of target materials (Si and Ge) and ion beam (Ar+ and Kr+) species. Average energies of sputtered atoms and reflected particles show a strong emission-angle-dependence and therefore the position of the substrate during IBSD is an important factor in controlling the film quality.