The use of 3C-SiC wafers for device fabrication has been restricted by the high defect density in the substrates. Flash lamp annealing (the FLASiC process) has been shown to reduce the defect density in 3C-SiC by at least an order of magnitude. This process involves melting a layer of silicon in contact with the 3C-SiC layer on a time scale of milliseconds and the subsequent regrowth of the SiC layer by liquid phase epitaxy. This paper shows how the transport of carbon in the liquid silicon is determined by the structure of the starting substrate and process conditions. The movement of carbon controls the dissolution and regrowth of the SiC and determines the morphology of the regrown film. (c) 2005 Elsevier B.V. All rights reserved.