Photoluminescence and optically detected magnetic resonance were employed to study effects of non-stoichiometry during the growth on defect formation in ZnO epilayers grown by molecular-beam epitaxy. Several defects were revealed via monitoring the yellow photoluminescence emission (~2.17eV) and their magnetic resonance signatures were obtained. The defects were concluded to be common for the molecular beam epitaxial growth and were facilitated during the off-stoichiometric growth conditions, especially under excess of O.

Effects of Stoichiometry on Defect Formation in ZnO Epilayers Grown by Molecular-Beam Epitaxy - an Optically Detected Magnetic Resonance Study. Wang, X.J., Buyanova, I.A., Chen, W.M., Pan, C.J., Tu, C.W.: Journal of Applied Physics, 2008, 103[2], 023712