Composition profile of PLT films on YSZ-buffered (100)InP

The composition and interdiffusion profiles of (100/001)-oriented (Pb,La)Ti O3 films deposited on [100]{100}YSZ parallel to [100]{100}InP by pulsed las er deposition have been studied by X-ray photoelectron spectroscopy and Rut herford backscattering spectroscopy. These studies demonstrate the presence of a Pb-rich region in the first 10-20 nm below the film surface, which co nsists of an oxygen-chemisorbed lead and (Pb,La)TiO3 mixture. The Pb surfac e enrichment was clearly distinguished from the lead preferential sputterin g also present. Underneath the small. surface region, the film has a unifor m composition close to that of the piezoelectric Pb0.82La0.12TiO3. The PLT/ YSZ and YSZ/InP interfaces are much narrower than the YSZ thickness used (a pproximate to 150-200 nm). Thus, the YSZ buffer layer avoids Pb/In interdif fusion and deep reoxidation of InP and enhances the PLT orientation. This a llows the integration of piezoelectric PLT on InP.