Using anhydrous metal nitrates as single source precursors, combinatorial chemical vapor deposition was used to create compositional gradients in the bimetallic ZrO2/HfO2 system and the trimetallic ZrO2/HfO2/SnO2 system. Composition and structural information were probed simultaneously by measuring the fluorescence and diffraction resulting from exposure of the film to a 30 μm diameter X-ray beam at the Advanced Photon Source. The higher resolution made possible by the small beam size provided an accurate map of composition and structure. In the homologous zirconia-hafnia series a decrease in lattice constants and a change in film texture was observed as a function of increased Hf concentration. As reported elsewhere, at intermediate compositions, gradients involving ZrO2 and SnO2 or HfO2 and SnO2 give rise to a crystalline phase(α-PbO2 structure type) that differs from that found for either of the end members. The simultaneous measurement of fluorescence and diffraction coupled with the small spot X-ray source provides a more accurate correlation between composition and structure.
- Tin oxide