Single crystalline SnO2 thin films grown on m ‐plane sapphire substrate by mist chemical vapor deposition

• Published in: Physica status solidi. C Vol. 14; no. 1-2
• Main Authors: Yatabe, Zenji, Tsuda, Takaaki, Matsushita, Junya, Sato, Takehide, Otabe, Tatsuya, Sue, Koji, Nagaoka, Shoji, Nakamura, Yusui
• Format: Journal Article
• Language: English
• Published: Berlin WILEY‐VCH Verlag Berlin GmbH 01.01.2017; Wiley Subscription Services, Inc
• Subjects: Diffraction; mist−CVD; m‐plane sapphire substrate; single crystal; SnO2; Thin films
• ISSN: 1862-6351; 1610-1642
• DOI: 10.1002/pssc.201600148

Tin dioxide (SnO2) 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 SnO2 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 SnO2 films were epitaxially grown on the substrates under optimised growth condition. Epitaxial growth of SnO2 thin film growth at three typical areas on the substrate was confirmed by the EBSD measurements. It is likely that the single crystalline SnO2 (001) thin film was formed across the 2‐inch sapphire substrate. Finally, the second SnO2 layer was overgrown on the above single crystalline SnO2 thin film, which functioned as a buffer layer. This method which drastically improved surface roughness of the second SnO2 layer.