Effective Bond-Orbital Model of III-Nitride Wurtzite Structures Based on Modified Interaction Parameters of Zinc Blende Structures

A simple theoretical method for deducing the effective bond-orbital model (EBOM) of III-nitride wurtzite semiconductors from the zinc blende structure is presented. In the EBOM for a zinc blende structure one s-like and three p-like bond orbitals are assumed. The set of EBOM parameters are obtained by fitting the band energies at high symmetry points in reciprocal space with the first-principle calculation. It is shown that the band structures of the wurtzite structure can be produced by using the EBOM parameters derived for the zinc blende structure defined in the rotated frame by adding correction to three-center overlap integrals resulting from the rotation of atomic positions, which transfers the lattice symmetry from Td to C3v. Details of the parametrization of the EBOM Hamiltonian suitable for bulk III-nitride wurtzite semiconductors are presented. The band structures of bulk GaN, AlN, and InN with a zinc blende and wurtzite structure calculated in the same set of EBOM parameters with correction of three-center overlap integrals are presented and compared with first-principle calculations.