Powder heat-treated in NH3 atmosphere was investigated by electron paramagnetic resonance, photoluminescence, and Raman spectroscopy. It was found that the treatment created Zn interstitials (Zni) and complexes of Zn interstitials and N atoms replacing oxygen (Zni-NO). A correlation between the Zni and an exciton at 3.366eV (I3) could be shown by comparison with the photoluminescence results. The (Zni-NO) complex seemed to be related to a recombination at 3.193eV.

Zn Interstitial Related Donors in Ammonia-Treated ZnO Powders. Sann, J., Stehr, J., Hofstaetter, A., Hofmann, D.M., Neumann, A., Lerch, M., Haboeck, U., Hoffmann, A., Thomsen, C.: Physical Review B, 2007, 76[19], 195203