Defect-mediated kinetic roughening in low-temperature MBE growth of Si/Si (111)

¹ Centre de Recherche sur les Mécanismes de la Croissance Cristalline, CRMC2-CNRS Campus de Luminy, case 913, 13288 Marseille Cedex 09, France
² Centre de Physique Théorique, CNRS Luminy, Case 907, 13288 Marseille Cedex 09, France

Received: 17 March 1997
Accepted: 8 January 1998

Abstract

Far from equilibrium, various growth processes lead to rough surfaces and interfaces. Those roughening phenomena obey to universal scaling laws extensively studied recently. However, few recent reports mention an unexpected deviation from the scaling laws without any plausible statement. We achieve in this work a clear correlation between the surface roughness and the microscopic morphology of the growing layer, thanks to a theoretical probabilistic cellular automaton (PCA) and experimental (in situ RHEED and ex situ HREM) study of surface kinetic roughening in low-temperature MBE silicon homoepitaxy. A transition in the growth mechanisms between a perfect epitaxy regime and another one displaying structural defects is shown. It may explain previous unusually observed deviations of the surface roughness scaling behaviour unpreviewed by current theories.