The influence of substrate curvature on structural, optical properties of Cu, Co codoped ZnO thin films

• Cu, Co codoped ZnO thin films have been successfully prepared via a RF magnetron sputtering process.
• The biaxial stress of ZnO thin films is characterized by side-inclination X-ray diffraction XRD technique.
• The various substrates induce defect-related emission increase in visible region.

The influence of substrate curvature on structural, optical properties of Cu, Co codoped ZnO thin films were investigated in this study. XRD analysis indicated that the crystal quality of the ZnO films could been influenced by the substrate curvature. The biaxial stress of our samples was measured by side-inclination X-ray diffraction technique. The results indicated that the type of the stress was biaxial compressive stress. Optical absorption spectra showed the absorption edge of our samples displayed blueshift with decreasing substrate curvature. Gauss fit for PL emission spectra showed that the substrate curvature affected the PL properties of the Cu, Co codoped ZnO thin films deposited on polystyrene particles. The various substrates induced defect-related emission increased in visible region.