First-principles calculation of interfacial stability, energy, electronic properties, ideal tensile strength and fracture toughness of SiC/BN interface

Abstract

The interfacial properties and electronic structure of $$\beta$$ -SiC (111)/ $$h$$ -BN (0001), including work of adhesion (Wad), interface energy, bonding nature, ideal tensile strength and fracture toughness, were investigated using first-principles calculations. Eight interface models, with two different terminations and four stacking sites, were investigated. The $$\beta$$ -SiC (111) slab, with 10 atomic layers, and the $$h$$ -BN (0001) slab, with two atomic layers, exhibited bulk-like interior features, respectively. The Case II interface, in which the Si atom was located at the center of the B-N bond, had the largest work of adhesion (2.749 J/m2), the smallest interfacial distance (2.02 A), the minimum interface energy (0.473 J/m2) and, thus, the best stability. The valence electron density and partial density of states indicated that there was a strong chemical and electrical interaction between the two sides of the Case II interface. The electronic structure analysis suggested that the interfacial bonding was mainly attributed to the Si-N ionic interaction and the valence electronic hybridization between Si-sp and B-sp. The ideal tensile strength and fracture toughness of the Case II interface were predicted as 13.26 GPa and 0.68–1.887 MPa•m1/2, respectively.