KNN lead-free technology on 200 mm Si wafer for piezoelectric actuator applications

State-of-the-art (K,Na)NbO3 (KNN) films were integrated into MEMS actuator devices in a 200mm silicon wafer technology environment following industry compatible process. The ferroelectric, dielectric and piezoelectric properties of KNN films with a thickness of 1µm and 1.9µm integrated into capacitors were assessed throughout the whole 200mm wafers. The actuator behaviour was highlighted through electromechanical measurements on KNN based devices such as cantilever beams and membranes. KNN was eventually used to actuate micro-mirrors, one of the main piezoMEMS components that may drive the market in the near future. The results demonstrate that KNN technology is promising for replacing lead content PZT technology in piezoelectric MEMS industry.