Enabling Fabrication of PZT Based PiezoMEMS Devices

We report a robust process flow for fabrication of PiezoMEMS devices with Lead Zirconate Titanate thin film as the active piezoelectric material. This process flow can overcome all contamination issues that plague processing PZT thin films in a shared facility. We use wet etch recipes for etching of the bottom electrode (platinum) and PZT. We propose sidewall coverage of PZT and Pt film while carrying out deep silicon etch in DRIE to avoid possible exposure of these contaminating materials to the tool. With this process, we have fabricated a gyroscope structure with electrostatic comb drive actuation and piezoelectric sensing. The structure is tested for actuation using PZT film on the beam just to verify the integrity of the active layer.