An analysis of experimental data on the influence of native defects of the
crystalline lattice on polytypism in silicon carbide has been performed. A
simple analytical expression, which links the degree of hexagonality of the
polytype with the concentration of carbon and silicon vacancies, was obtai
ned. The possible dependence of the model parameters on the experimental co
nditions is investigated. (C) 1999 American Institute of Physics. [S1063-78
26(99)00107-6].