Effect of K–N on the structural and optical properties of K–N co-doped ZnO film

N-doped and K–N co-doped ZnO thin films were prepared by chemical bath deposition. The effects of dopants on the microstructure and the optical properties of ZnO thin films are studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), room-temperature photoluminescence and Raman spectroscopy. The results show that the replacement of K ion in ZnO film may lead to the expulsion of the N ion from the lattice of ZnO, which leads to a change of the PL intensity of ZnO films. This conclusion was also proved by the Raman spectra, in which a new peak, centered at 287 cm−1, emerged with the increase of K concentration.