Effect of Al Excess on the Band Structure of ZnO Using Density Functional Theory

Abstract

The effect of Al doping to the band structure of ZnO was studied in this paper. The electronic band structure of Al doped ZnO was determined by using first-principles based on density functional theory. ABINIT was used to perform the band structure calculation. The calculated band structure of ZnO and Al doped ZnO shows that ZnO is a direct band gap semiconductor. The band structure become narrow with Al doping compared pure ZnO. With Al doping, the band gap of ZnO (0.749 eV) become smaller as the concentration Al doping increased to 4wt% (0.551 eV). The electrical conductivity of Al doped ZnO was studied as a references value for the band gap. The electrical conductivity of ZnO (8.21 S/cm) was enhanced with Al doping increased to 4wt% (71.87 S/cm).