We report modeling of experimental B diffusion profiles in SiC which were measured by means of secondary ion mass spectrometry (SIMS) after B implantation and subsequent diffusion annealing at temperatures between 1790 degreesC and 1800 degreesC. Transient enhanced B diffusion caused by implantation damage was effectively reduced by recovery annealing of the B-implanted samples at 900 degreesC prior to the diffusion anneal. Concentration profiles of B are accurately described on the basis of the kick-out mechanism. Simulations based on this model also accurately reproduce the diffusion from a buried B-doped SiC layer into undoped SIC epitaxial layers. This shows that Si self-interstitials rather than Si vacancies control the diffusion of B in SIG. Moreover, a suppression of B diffusion in SiC coimplanted with C can be explained by taking additionally into account the formation of SI-C pairs.