Micromachined pmn-pt single crystal for advanced transducers

Abstract

In this paper a deep reactive ion etching (DRIE) process developed for the micromachining of bulk piezoelectrics is discussed. For the first time, a PMN-PT single crystal piezoelectric micro-array was fabricated with an array post cross section size of 14 µm x 14 µm, a height of >60 µm, and a spacing between microposts of about 2-6 µm. The etched single crystal piezoelectrics retained high piezoelectricity (d33 ~2000 pC/N) and low dielectric loss (<0.01). Single crystal/epoxy 1-3 composites were fabricated using the etched micro-arrays and the electromechanical coupling coefficient of such piezoelectric composites was ~0.72, indicating promising applications such as micro-sensors, actuators and transducers.