Structural characteristics of RF-sputtered BaTiO3 thin films

In this work some structural characteristics of the thin films deposited by a radio frequency-magnetron sputtering technique from a hot pressed BaTiO3 ceramic target were studied. The Ba/Ti ratio was measured by means of X-ra y fluorescence in order to determine the real chemical composition of the f ilms. The results showed that this ratio varied along the radial axis of th e discharge. Besides, the evolution in phase composition of the annealed fi lms as a function of the thermal treatment conditions (temperature and plat eau) as well as the structural characteristics (unit cell parameter and cry stallite size) were investigated by X-ray diffraction (XRD). Infrared (IR) and Raman spectroscopies were used in order to obtain more details about th e distorted structure of such fine-grained thin films. In the case of these films, Raman spectroscopy carried out from 99 to 473 K did not emphasize s teep, distinct transitions between the different polycrystalline BaTiO3 for ms when compared with the bulk BaTiO3. (C) 2001 Elsevier Science B.V. All r ights reserved.