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Abstract: MgZnO films with different Mg contents were synthesized on c-plane sapphire by metal organic chemical vapor deposition, using diethyl zinc (DEZn) and bis(cyclopentadienyl) magnesium (Cp2Mg) as Zn and Mg precursors, respectively. Tertiary butanol (t-BuOH) was used as a weak oxidant in order to enhance the accuracy of Mg incorporation when varying DEZn/Cp2Mg flow rates. As a result the Mg contents in the range of 1–9% were confirmed by time-of-flight elastic recoil detection analysis, which is known to be specifically sensitive to detect light elements. Thus, independently and accurately determined composition in the samples was correlated with structural and optical properties as measured by x-ray diffraction and photoluminescence. [Copyright &y& Elsevier]

Abstract: Single-crystalline ZnO film with two-dimensional periodic structure was grown on Si(111) substrate by radio-frequency plasma-assisted molecular beam epitaxy. The influence of substrate orientations and growth temperatures was explored for achieving a high-quality ZnO film. It was found that ZnO epilayers grown on Si(111) substrate have better crystalline quality than the one on Si(100), and a higher growth temperature was further confirmed favorable for the attainment of a periodic morphology. The results suggest that our growth method is feasible for the fabrication of ZnO film with periodic structure, which is promising for applications in new photonic devices. [Copyright &y& Elsevier]

Abstract: A route for realizing non-polar ZnO (112̄0) films with atomically smooth surface is demonstrated by employing rf-plasma assisted molecular beam epitaxy on ZnO bulk substrates. It is found that high growth temperature plays an important role in suppressing the typical striped structure along ZnO [0001] direction on non-polar planes. An atomically smooth surface with a root mean square roughness of 0.51nm that is suitable for fabrication of quantum wells is achieved after solving the growth anisotropy problem, as confirmed by the combined studies of reflection high-energy electron diffraction and atomic force microscopy. [Copyright &y& Elsevier]

Abstract: A route for synthesizing high Mg content single-phase wurtzite MgZnO films having band gaps in the solar-blind region is demonstrated by employing molecular beam epitaxy on Al2O3 substrates. Importantly, a low Mg content “quasi-homo” buffer, Mg0.17Zn0.83O, was applied to accommodate a host of structural discrepancies and therefore, avoiding phase separation in a high Mg content film, Mg0.55Zn0.45O, as proved by X-ray diffraction. The Mg fraction in the overgrown single-phase epilayer, Mg0.55Zn0.45O, was confirmed by Rutherford backscattering spectrometry. [Copyright &y& Elsevier]