A detailed numerical study was made of a simple model for epitaxial growth on a 1-dimensional substrate. The model incorporated random deposition and isotropic surface diffusion, and allowed for the formation of bulk defects. The interplay between bulk defects and surface roughening was examined, and it was shown that the short-term short-range behavior of the surface fluctuations corresponded quantitatively to that which had been observed previously in various solid-on-solid models, whereas the long-term long-range behavior was described by the Kardar-Parisi-Zhang theory. It was proposed that the cross-over between the 2 regimes was triggered, via the surface-induced formation of elongated bulk defects, by large local surface height gradients in the solid-on-solid regime.

M.Schimschak, J.Krug: Physical Review B, 1995, 52[11], 8550-63