Nonlinear diffusion equation for crystal growth on stepped surfaces

Abstract
An equation that includes both adatom diffusion and diatomic island formation is derived for describing growth on stepped surfaces. The equation is integrated numerically to obtain adatom and island concentration profiles along the terraces. Comparison of this solution with experimental measurements on vicinal GaAs(001) for a variety of Ga and As2 fluxes and with Monte Carlo simulations shows that inclusion of island formation in the growth equation is crucial in determining the temperature beyond which growth becomes dominated by step propagation.