Edelmann, F., Hahn, H., Seifried, S., Alof, C., Höche, H., Balogh, A., Werner, P., Zakrzewska, K., Radecka, M., Pasierb, P., Chack, A., Mikhelashvili, V., Eisenstein, G.
Structural evolution of SnO2-TiO2 nanocrystalline films for gas sensors
Materials Science & Engineering B 69/70, (Special Is),pp 386-391 (2000)
Thin films (50-200 nm) of SnO2-TiO2 were deposited on SiO2/(001)Si substrates by RF-sputtering and by molecular beam before they were annealed in vacuum at 200-900 degrees C. In-situ TEM, XRD, SEM, Raman and IR-spectroscopy were used to analyze the structure transformations in the SnO2-TiO2 films. In the as-deposited state, the films are amorphous. They crystallize at higher temperatures (starting at about 500 degrees C) forming nanosized grains. The problem of the spinodal decomposition in the SnO2-TiO2 system observed earlier at high temperatures is discussed also for low-temperature processing. The stoichiometry of the films of both groups (reactive ion sputtered and high-vacuum e-gun sputtered) is being compared. (C) 2000 Elsevier Science S.A. All rights reserved. [References: 23]