Effects of growth interruption of ZnO buffer layers on the structural and the optical properties of ZnO thin films grown by using PA-MBE

ZnO thin films with ZnO buffer layers were grown on Si substrates by using plasma-assisted molecular beam epitaxy (PA-MBE). The ZnO buffer layers were grown with the growth interruption technique. The structural and the optical properties of the ZnO thin films were investigated by using X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), and photoluminescence (PL). The surface morphology of the ZnO thin films was changed from an island to a net-like shape. An evident net-like shape was observed, and the optical properties were enhanced with increasing number of growth interruptions.