High Piezoelectric Coefficient Ferroelectric Films for MEMS Applications

Piezoelectric thin films are attractive elements in several MEMS applications due to the large generated force, high electromechanical coupling coefficients, and substantial charge output that can be generated. This proposal focuses on two approaches to increasing the performance in piezoelectric MEMS devices: (i) enhancing the effective piezoelectric response in thin ferroelectric films utilizing in-plane poled structures and (ii) developing miniaturized flextensional transducers to amplify the piezoelectric effect. From the scientific standpoint, the program will determine how the piezoelectric properties of in-plane polarized lead zirconate titanate films compare to through-the-thickness polarized transducers, as well as any differences in the way piezoelectric and dielectric properties age and fatigue relative to conventionally poled films. A processing scheme to enable production of flextionsional MEMS transducers will also be developed. In addition, a MEMS switch for RF applications with large displacement (~2 microns) and high-speed (