Measurement of Effective Longitudinal Piezoelectric Coefficient of thin Films by Direct Piezoelectric Effect

This paper presents a new method for the measurement of the longitudinal piezoelectric coefficient of piezoelectric thin films using the direct piezoelectric effect. A uniform uniaxial stress was applied to the piezoelectric thin film by high-pressure gas and the induced charge was collected and measured by a charge integrator. The effective longitudinal piezoelectric coefficient of lead zirconate titanate (PZT) 52/48 thin films made by sol-gel processing was measured by this method. Undoped films typically have d 33 values of ∼ 5 pC/N, while poled films have values up to 220 pC/N.