Silicon photonics has been witnessing an influx of new technologies and functionalities realized through hybrid integration of new materials. One of the most promising materials recently added into this list is a photonic compatible (low-optical loss) Lead Zirconium Titanate (PZT) thin film. Bulk PZT is known for its high piezoelectric and electromechanical coupling coefficients. Integration of a PZT thin film can introduce a strong piezoelectric effect as a new feature to the Silicon-on-insulator (SOI) platform. In this work we explore the piezoelectric property of this PZT film deposited on an SOI substrate through electro-mechanical actuation. We fabricate microscale cantilever beams by under-etching the buried oxide in the PZT/SOI with HF vapor. We characterize the mechanical vibration of these MEMS actuators with a Laser Doppler Vibrometry (LDV). We demonstrate a shear vibration mode with the as-deposited PZT film (domains preferentially out of the substrate plane) and a longitudinal vibration mode after poling the PZT domains along the applied electric field. This opens the possibility of integrating PZT thin film based MEMS actuators and transducers into Silicon photonic integrated circuits (PICs).
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