Fabrication and function examination of PZT-based MEMS accelerometers

In this study, a hybrid sol-gel method was used to fabricate Pb(Zr0.52Ti0.48)0.98Nb0.02O3 (PNZT) piezoelectric thick films. By preparing Pb(Zr0.52Ti0.48)0.98Nb0.02O3 sol-gel solutions and mixing them with PZT-5A piezoelectric powders, therefore, the thickness of single layer coating can be increased and reduce the risk of film cracks. The proposed PNZT films have the dielectric constant of 1750, dielectric loss of 0.063, remnant polarization of 58 mu C/cm2, and d33 of 133 p.m./V. Piezoelectric cantilever beam MEMS accelerometers were then designed, simulated and fabricated via photolithography methods on Si substrates. The sensitivity and natural frequency of the cantilever beam accelerometer are 16.8 mV/g and 200Hz, respectively. Finally, a cantilever beam accelerometer is successfully applied for the server hard-drive fault detection.