Low Temperature Chemical Vapor Deposition As a Sustainable Method to Obtain C-Oriented and Highly UV Luminescent ZnO Thin Films

We report the fabrication of c-oriented and transparent ZnO films with high UV/visible luminescent ratio on glass substrates using a very simple low temperature-atmospheric pressure chemical vapor deposition technique, where zinc acetate (ZA) and water vapor were the precursors. Both the ZA source and the glass substrate are in a same work temperature zone (240 degrees C) and no vacuum system is necessary. Highly c-oriented ZnO films were obtained with different growth rates (similar to 2 to 44 nm/min) by varying the source-substrate distance. The samples were characterized by scanning electron microscopy, X-ray diffraction and UV-vis, photoluminescence (PL) and energy-dispersive X-ray spectroscopies. Films grown with the highest growth rate exhibited narrower bandgap, which is correlated with a violet component in the PL spectra.