Effects of N on Electronic and Mechanical Properties of H-Type SiC**Supported by the National Natural Science Foundation of China under Grant No 51372203, the National Basic Research Program of China under Grant No 2011CB605806, the Basic Research Foundation of Northwestern Polytechnical University under Grant Nos JCY20130114 and JCY20110248, and the Foreign Talents Introduction and Academic Exchange Program under Grant No

Abstract

Structural, electronic and mechanical properties of the nH-SiC (n = 2, 4, 6, 8 and 10) polytypes are calculated by using the first-principles calculations based on the density-functional theory approach. The optimized lattice parameters of nH-SiC are in good agreement with the experimental data. The mechanical properties, including elastic constants, bulk modulus, Young's modulus, shear modulus and Poisson's ratio, are calculated. The analysis of elastic properties indicates that the effects of n on the mechanical properties of the five nH-SiC structures have no difference. The indirect band gap relationship for the five polytypes is Ebg2H > Ebg4H > Ebg6H > Ebg10H > Ebg8H.