Lattice and electronic structures of BAlN in the deep ultraviolet spectral region

Abstract

BAlN exhibit intriguing properties for both fundamental research and potential application in optoelectronic devices operating in the deep ultraviolet spectral ranges. For BxAl1-xN, the crystal lattice constant derived for the whole range of the alloy composition closely follows Vegard's law. The mechanical stability is represented by elastic constants. The fundamental bandgap is converted from direct in AlN to indirect in BN. The orbital projected band structure of BAlN is obtained to gain insight into the electronic structure and the optical anisotropy with favorable light polarization is understood in terms of the crystal field split-off energy. The band structure parameters including the band gap, the effective masses of electrons and holes are presented and the corresponding electron mobility of BAlN with the direct band gap are predicted to be larger than that of AlN. It is worth noting that BAlN with the direct band gap are quite promising for application in electronic and optoelectronic devices operating in the UVC range.