First-Principles Study of AlBN and Related Polytypes

Abstract

We have investigated the electronic and lattice properties of AlBN and related ternary polytypes which are sp³-bonded compounds. Considered polytypes are 2H-, 3H-, 4H-, 5H-, 6H-, 3×2H-, and 12H. Internal atoms (Al or N) of AlN polytypes replaced with B, P, or As atoms as AlBN, AlPN, and AlAsN. Their electronic and lattice properties are optimized automatically by the first-principles molecular dynamics (FPMD) method. Their electronic band structures are non-metallic with the exception of 2H-AlBN(Al₂BN), 4H-AlAsN(Al₄AsN₃), 4H-AlAsN0(Al₄As₂N₂), and 4H-AlPN(Al₄PN₃). Most band gaps of calculated AlBN polytypes are indirect. One 3×2H-AlBN(Al₅BN₆) structure has a direct band gap although the band gaps of other calculated 3×2H-AlBN are indirect.