Sintering of thin film nanocrystalline titania–tin oxide composites

Thin nanocrystalline titania films were sintered on dense substrates with the addition of tin(IV) oxide as a possible grain growth inhibitor. Densification and the development of the pore size distribution were examined via nitrogen adsorption. Aberration-corrected scanning transmission electron microscopy (STEM) and X-ray energy dispersive spectroscopy (XEDS) studies combined with X-ray spectroscopy measurements were carried out to investigate the tin and titanium distribution in the thin films. These studies showed that the additions of SnO2 have little influence on grain growth during sintering of nanocrystalline titania films, but can strongly affect the phase transition from anatase to rutile. The influence of this phase transition during sintering in thin films and the effect on the in-plane biaxial stresses is highlighted.