The incorporation of the acceptor boron during vapor growth (PVT) of 6H-SiC bulk crystals has been studied. The chemical segregation coefficient of boron (ratio between B content of the grown crystal and of the source) has been determined to be 0.4±0.1 for a wide range of B concentrations in the starting material (0.3-300 ppm wt). For reference purposes the impurity concentrations in nominally undoped SiC crystals have been analyzed. Whereas both source and SiC crystals exhibit a high purity in regard to p-type (Al, B) and deep level (V, Ti) impurities, a considerable amount of residual nitrogen was detected resulting in carrier concentrations n = 1×1016 to 1.5×1017 cm-3. Carrier concentrations in the p-type B doped crystals were found to range from 2×1014 to 2×1016 cm-3 for starting B concentrations between 3 to 300 ppm wt. Axial non-uniformities, i.e. carrier concentration in SiC:B increases with crystal length, depend on the compensation ratio. At higher B content the homogeneity improves. Compared with segregation in Al doped SiC, results indicate that SiC:B powder acts as infinite, SiC:Al powder as finite dopant source. The lateral distribution of carrier concentration in SiC:B crystals (wafer mapping) has been measured showing a good homogeneity of electrical properties.