Comparative study of room temperature ferromagnetism in Cu, Co codoped ZnO film enhanced by hybridization

A series of Cu and Co codoped ZnO thin films with different Cu content were prepared using the RF magnetron sputtering method. The XRD results indicated that the crystal quality of the ZnO films were influenced by the level of Cu-doping during the sputtering process. X-ray photoelectron spectroscopy was used to detect the elemental valence states of Zn, Co, Cu and O. Magnetic measurements showed that the Cu and Co codoped ZnO thin films displayed room temperature ferromagnetism. The enhanced FM in the Cu, Co codoped ZnO can be attributed to the 3d orbitals split of Cu2+. The results of the absorption spectra showed that the bandgap of the ZnO thin films narrow down caused by the Cu doping. It also can be attributed to 3d orbitals split which further supported our interpretation of magnetic.