Energetics and Electronic Structure of Stacking Faults in ZnO

The energetics and electronic structures of basal-plane stacking faults in wurtzite (WZ) ZnO are studied using first-principles density-functional total energy calculations. All the basal-plane stacking faults are found to have very low formations energies. They also introduce a downward shift at the conduction-band minimum (CBM). However, plane-averaged charge densities of the CBM state reveal that the CBM states are not very localized, indicating that these stacking faults should be electronically inert. The high concentration of these stacking faults can result in embedded zinc-blende (ZB) ZnO surrounded by WZ materials. The WZ/ZB interface exhibits a type-II lineup with ΔE _V≈0.037 eV and ΔE_C≈0.147 eV.