O. Pierre-Louis1,2 and T. L. Einstein1

In addition to the usual step Ehrlich-Schwoebel effect (SESE) on typical metal and semiconductor surfaces, there can also be a kink Ehrlich-Schwoebel effect (KESE), associated with asymmetries in barriers at kinks/corners encountered by atoms during transport along step edges[1]. We take into account both phenomena to study the evolution of arbitrarily oriented surfaces during growth. We find that the heretofore rarely discussed[2] KESE has a profound effect on growth morphology. Under the usual growth conditions, KESE turns out to induce a new instability of vicinal surfaces, supplanting the familiar Bales-Zangwill instability[3], due exclusively to SESE. The possibility of stable kink-flow growth is analyzed; fluctuations can shift the stability threshold. For some orientations, steps can also be stablized by KESE. Finally KESE can induce mound formation. In addition to analytic predictions, numerical results [1,4] are provided.

Work supported by NSF MRSEC grant DMR 96-32521.

1. O. Pierre-Louis, M. R. D'Orsogna, & TLE, Phys. Rev. Lett. 82, xxx (1999).

2. See, however, Z. Zhang and M. G. Lagally, Science 276, 377 (1997).

3. G.S. Bales and A. Zangwill, Phys. Rev. B 41, 5500 (1990).

4. M. V. Ramana Murty and B. H. Cooper, preprint.