Calculations of electronic structure and density of states in the wurtzite structure of Zn(1) (-) (x)Mg(x)O alloys using sp(3) semi-empirical tight-binding model

Abstract

Calculating the electronic structure and the density of states in the wurtzite structure of Zn(1) (-) (x)Mg(x)O(ZMO) alloys using sp(3) semi-empirical tight-binding model, we observed increases of both band gap and electron effective mass that agree with the experimental results as increasing Mg composition up to x = 0.3. From the calculated total density of states, the increasing electron effective mass is a result of less orbital overlap of cation sites due to extra density of modes coming from Mg3s and Mg3p orbitals as introducing more Mg composition. Additionally, reducing electronegative characteristic of oxygen was caused by that the O2p was less localized around the oxygen atom.