  Ferroelectric materials exhibit interesting electric, mechanical and optical
properties. Particularly,tin-film lead zirconium titanate (PZT) has been used
as a standard piezo-electric material in micro-electro-mechanical systems.
Interestingly, it has one of the highest electro-optic properties that can be
exploited to make high-speed on-chip light modulators. In this work, we
demonstrate sputter-deposited PZT on silicon-on-insulator wafers. Desired phase
and film morphology is achieved through process and buffer layer engineering.
We present results on buffer layer screening between MgO, TiO2 and Pt. MgO is
identified as a suitable buffer layer from an optical and film growth
perspective. We achieve a measured coercive field for PZT/MgO and PZT/Pt film
is 50 kV/cm and 30 kV/cm, respectively. We use a PZT-loaded ring modulator with
an electro-optic response of 14 pm/V.
