Dynamic testing of micro devices using PZT base excitation

Abstract

Dynamic testing of micro devices by lead zirconate titanate (PZT) base excitation is presented in this work. Followed with a brief discussion of base excitation principle, the suitability of piezoelectric plate for high bandwidth vibration excitation is revealed. To compare the dynamic testing results based on this method, a 1.21mm (L) by 0.52mm (W) PZT micro cantilever with self-exciting capability is designed and fabricated by a sol-gel process. The fabricated PZT micro cantilever beam is then attached to a 10mm by 10mm by 1 mm piezoelectric plate (PI piezoceramic). A Polytech scanning laser Doppler vibrometer (SLDV) system is used to measure the resonance frequencies and corresponding modal shapes of the micro cantilever beam under the piezoelectric plate base excitation and the PZT micro cantilever self-excitation, respectively. It is found that piezoelectric plate base excitation would be more powerful than self excitation to stimulate the mode shapes of a micro device under testing.