Abstract:
We report on the studies carried out on hydrogen peroxide treated melt grown, bulk single
crystal ZnO samples. Results show the existence of two shallow donors in the as-received
ZnO samples with energy levels (37.8 ± 0.3) meV that has been suggested as Zni related and
possibly H-complex related and (54.5 ± 0.9) meV which has been assigned to an Al-related
donor. Annealing studies performed on the hydrogen peroxide treated samples reveal the
existence of a conductive channel in the samples in which new energy levels have been
observed, Zn vacancies, related to the Group I elements, XZn. The surface donor volume
concentration of the conductive channel was calculated from theory developed by D. C. Look
[1]. Results indicate an increase in surface volume concentration with increasing annealing
temperature from 6.0´1017 cm-3 at 200°C to 4.37´1018 cm-3 at 800°C.
