Influence of the Annealing Temperature on the Properties of {ZnO/CdO}30 Superlattices Deposited on c-Plane Al2O3 Substrate by MBE

{CdO/ZnO}_m superlattices (SLs) were grown on c-plane sapphire substrates using plasma-assisted molecular beam epitaxy (PA-MBE). The presence of a periodic superlattice structure was confirmed by the observation of satellite peaks in the XRD studies of both as-grown and annealed samples. The properties of the as-grown and annealed SLs deposited on c-oriented sapphire were investigated using Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), and temperature-dependent photoluminescence (PL) studies. The deformation of the SLs structure was observed after rapid thermal annealing. As the annealing temperature increased, the diffusion of Cd ions from the quantum well layers into the ZnO barrier also increased. The formation of CdZnO layers led to changes in the luminescence spectrum, including peak shifts, broadening, and alterations in the spacing of the satellite peaks visible in the X-ray analysis.