Homoepitaxial growth on off-axis alpha-SiC (0001) at reduced pressures in a horizontal cold-wall chemical vapor deposition (CVD) system operating at 1500 degreesC has been investigated. The growth rate was found inversely proportional to the square root of total pressure or the partial pressure of H-2, a carrier gas. A model to explain the experimental results is proposed, where the rate-determining process in CVD is competition between Si species and hydrogen atoms for C (carbon) dangling bonds at SiC step edges. (C) 2004 Elsevier B.V. All rights reserved.