Metal-organic vapor phase epitaxial growth of high-quality ZnO films on Al₂O₃(00·1)

High-quality ZnO thin films were grown epitaxially at 250–550 °C Al₂O₃(00·1) substrates using low-pressure metalorganic vapor phase epitaxy. The reactants for the growth were diethylzinc and oxygen. Growth temperature, one of the important experimental parameters for epitaxial layers, was optimized. The films grown at 500 °C exhibited good crystallinity and strong ultraviolet absorption and emission. Photoluminescence spectra of the films showed a dominant excitonic emission with a weak deep level emission. More importantly, a strong stimulated emission peak was observed even at room temperature.