SiC thermal conductivity: calculation of the isotope effect from first principles

The thermal conductivity temperature dependence kappa(T) of a hexagonal 2H-SiC silicon carbide crystal was calculated using the first-principle approach for orientation heat flux in basal plane and along axis c range from 100 to 500 K. effect carbon isotopic disorder on is considered. It found that, at 300 K, isotopically pure containing 100% 28 Si 12 C higher by 15.2% 12.4% directions across plane, respectively, than that crystals with natural composition isotopes. For mixture isotopes textnat C, isotope 14.5% 11.9% these directions. Keywords: single crystal, conductivity, carbide, first principle calculation.