Voltage monitoring hydrostatic pressure method for measuring the force sensitivity of piezoelectric films

A simple nondestructive method for measuring the force sensitivity of freestanding piezoelectric films is presented. The principle used is the direct piezoelectric effect, and the force sensitivity of the film is calculated by measuring the charge generated across the film and the magnitude of the applied pressure. A hydrostatic pressure is generated by pressurizing the oil in the chamber using a voice coil actuator. This method is capable of measuring the force sensitivity in the range of millinewton with a simple sample preparation in the form of a parallel plate capacitor structure. This straightforward measurement also results in improved electrical characterization of the piezoelectric capacitor and is suitable for the low-cost testing of microelectromechanical systems.