Abstract
We show that in epitaxial growth, there is a critical island size at which a second layer nucleates on top of the island. This provides a simple perspective on the conditions for smooth versus rough growth: For island spacing , if < the islands will nucleate a second layer before coalescence, giving multilayer growth. This occurs when there is a sufficiently large diffusion barrier (the ‘‘Schwoebel barrier’’) at the island edge. We demonstrate that surfactants can enforce layer-by-layer growth by reducing the island spacing. The dependence upon temperature is also explained.
- Received 23 August 1993
DOI:https://doi.org/10.1103/PhysRevLett.72.266
©1994 American Physical Society