Single crystalline SnO 2 thin films grown on m ‐plane sapphire substrate by mist chemical vapor deposition

Tin dioxide (SnO 2 ) thin films, as a candidate for realizing next‐generation electrical and optical devices, were grown on 2‐inch diameter m ‐plane sapphire substrates by mist chemical vapour deposition at atmospheric pressure. The SnO 2 thin films were characterized by scanning electron microscope (SEM), atomic force microscope (AFM), X‐ray diffraction (XRD) in θ–2θ and φ scanning modes, and electron backscatter diffraction (EBSD). Although the SEM and AFM images showed a relatively rough surface morphology, it was found from the XRD and EBSD measurements that SnO 2 films were epitaxially grown on the substrates under optimised growth condition. Epitaxial growth of SnO 2 thin film growth at three typical areas on the substrate was confirmed by the EBSD measurements. It is likely that the single crystalline SnO 2 (001) thin film was formed across the 2‐inch sapphire substrate. Finally, the second SnO 2 layer was overgrown on the above single crystalline SnO 2 thin film, which functioned as a buffer layer. This method which drastically improved surface roughness of the second SnO 2 layer.