Structural and optical properties of Cu–N codoped ZnO thin films deposited by magnetron cosputtering

ZnO films codoped by copper and nitrogen were prepared by magnetron cosputtering. The effects of this codoping on the structural and optical properties of ZnO films were systematically studied. The results show that Cu–N codoping didn’t affect the optimal orientation. Cu–N codoping can enlarge the grain size, enhance the crystallinity, reduce the stress and lead to denser and smoother surface. A significant red shift of absorption edge and gap-narrowing effect resulting from codoping were found in ZnO films. Cu-doping, N-doping, and oxygen vacancy are the main factors leading to property modification of the ZnO films. By Cu–N codoping, we can modulate the microstructure and optical properties of ZnO films in a wider range.