The suppression of oxygen vacancy (Ov) defects in BeO-alloyed ZnO films was reported. The alloy films were grown by plasma-assisted MBE on the sapphire substrates with a designed buffer layer. The decreased formation of Ov with the increase of Be content in BeZnO alloys was confirmed by the X-ray photo-electron spectroscopy and positron annihilation spectroscopy measurements. Hall measurements showed a "V" curve of the electron concentration and a flip-over "V" curve of the electron mobility as a function of Be content. The turning points of both curves were for the samples prepared at TBe = 960C. The turning points implied that there was a narrow growth window for optimum electrical properties of the BeZnO alloys, where the background electron density was almost one order of magnitude lower than the others, while the mobility was four times higher. The results on electrical properties were also supported by high-resolution X-ray diffraction.

Suppression of Oxygen Vacancies in Be Alloyed ZnO. Chen, M., Zhu, Y., Su, L., Zhang, Q., Xiang, R., Gui, X., Wu, T., Cao, X., Zhang, P., Wang, B., Tang, Z.: Journal of Alloys and Compounds, 2013, 577, 179-82