The dielectric and polar properties of thin films of aluminum nitride (AlN) epitaxially grown on variously oriented p-type silicon substrates with a buffer sublayer of silicon carbide (SiC), as well as on vicinal planes, are studied. According to the results of studies of the polar properties by two independent methods — the dynamic pyroelectric effect and piezoelectric force microscopy, it was shown that the use of a SiC buffer layer significantly improves the polar properties of thin layers of aluminum nitride.