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Piezoelectric thick films have increasing interest due to the potential high sensitivity and actuation force for MEMS sensors and actuators. The screen printing technique is a promising deposition technique for realizing piezoelectric thick films in the thickness range from 10-100 μm. In this work integration of a screen printed piezoelectric PZT thick film with silicon MEMS technology is shown. A high bandwidth triaxial accelerometer has been designed, fabricated and characterized. The voltage sensitivity is 0.31 mV/g in the vertical direction, 0.062 mV/g in the horizontal direction and the first mode resonance frequency is 11 kHz. A Finite Element Method (FEM) model is used to validate the measured sensitivity and resonance frequency. Good agreement between the model and the measurements is seen.

Abstract-We present a mechanical model of a triaxial micro accelerometer design using PZT thick-film as the sensing material. The model is based on the full anisotropic material tensors and Eulers' beam equation using simplifying assumptions where the smaller stress contributions are ignored. The model results in design equations that are useful for optimization of the sensitivity and bandwidth and for matching the sensitivity in the three orthogonal directions. A finite-element method (FEM) model is used to verify the analytical model. Equal sensitivity in all three geometrical directions is preferred, which induces a number of limitations in design parameter space, this is used in a design strategy for setting the six independent dimensions of the accelerometer. Design methods for optimum sensitivity of each axis and for equal sensitivity between different axes have been proposed.