Aluminum and nitrogen impurities in Wurtzite ZnO: first-principles studies

• Published in: Physica. B, Condensed matter Condensed matter, 2011-09, Vol.406 (17), p.3125-3129
• Main Authors: Li, P., Deng, Sh.H., Li, Y.B., Huang, J., Liu, G.H., Zhang, L.
• Format: Article
• Language: English
• Subjects: Aluminum; Condensed matter; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Dopants; Doping; Electron states; Energy of formation; Exact sciences and technology; Fermi surface: calculations and measurements; effective mass, g factor; First-principles; Ii-vi semiconductors; Impurities; Impurity and defect levels; Mathematical analysis; Physics; Zinc oxide; ZnO
• ISSN: 0921-4526; 1873-2135
• DOI: 10.1016/j.physb.2011.03.079

First-principles calculations have been performed to investigate the doping behaviors of Al and N dopant impurities in ZnO. According to the results, in the Al mono-doping case, the impurity states are quite delocalized, the corresponding effective masses are small, and the formation energy is as low as −9.71 eV. In the N mono-doping case, the impurity states are localized, the effective masses are large, and the formation energy is high (4.55 eV in the most favorable extreme O-rich conditions). In the Al–N codoping case, the corresponding effective masses are marked decreased compared to the N mono-doping situations, and the formation energy of the N–Al–N system is as low as −2.54 eV in the O-rich condition. The above results can explain the electrical behaviors of the doped or codoped ZnO systems observed in experiments.