COMPUTER-SIMULATION OF SURFACE GROWTH

A Monte Carlo model has been used to study surface growth in thin film epitaxy. The model accounts for atom attachment, detachment, and surf ace diffusion. By varying the deposition temperature and impingement r ate, we have explored the surface roughening transition in a nonequili brium situation and the conditions under which normal, lateral, and st ep flow growth occurs. The results show that reentrant oscillation occ urs as a result of the variation of surface diffusion length with depo sition temperature, and that it is a natural phenomenon in kinetic thi n film deposition on substrates with permanent steps. We have also exa mined the morphological instability in step flow growth and found that it is related to the step height. Steps with multi-atomic layers are seen to be less stable in a surface diffusion field, due to a decrease in the attachment rate of growth units from the upper terrace.