Competition between step-step elastic interaction and an Ehrlich-Schwoebel barrier in step bunching instability

Through a linear stability analysis of the competition between step-step elastic interactions and the asymmetry of adatoms incorporated from the terraces to the step edges in step bunching instability, growth mode diagrams were proposed with respect to the homo-epitaxial growth and hetero-epitaxial growth under various operating conditions and material properties. The force monopoles at the steps and the interaction of the force monopoles induce the step bunching on the vicinal surface. In contrast, the kinetic asymmetry of the adatom incorporation at the steps prevents the step bunching instability. The growth mode on the vicinal surface is determined by the competition between the elastic step-step interactions and the Ehrlich-Schwoebel barrier.