RAMAN-SCATTERING AND X-RAY-DIFFRACTION INVESTIGATIONS OF HIGHLY TEXTURED (PB1-XLAX)TIO3 THIN-FILMS

Highly textured lead lanthanum titanate (PLT) thin films grown on Si(1 00) substrates by the metalorganic chemical vapor deposition technique are characterized using x-ray diffraction (XRD), Raman spectroscopy, and energy-dispersive x-ray analysis. The texturing consisted of an al ignment of the {100} crystallographic axes of the film perpendicular t o the Si substrate. The tetragonality of the films was found to decrea se as the lanthanum concentration increased. Raman spectra exhibited f eatures characteristic of bulk PLT, including the observation of the s oft mode. Variations of the phonon modes for PLT have been investigate d as a function of La concentration and sample temperature.