Fabrication of AlN slender piezoelectric cantilevers for highspeed MEMS actuations

摘要

Very thin piezoelectric cantilevers based on AlN layers using titanium Ti thin film electrodes are fabricated and characterized. By optimizing the Ti sputtering parameters, a very low stress (156MPa) layers stack with high crystallinity and strong (002) orientation of the AlN films is obtained. Finally, a simple fabrication process, fully CMOS compatible, is developed to realize slender (900 nm) piezoelectric microcantilevers. A resonant frequency of 19.3 kHz is measured for 200 μm long cantilevers. The deflection of cantilever is 6 nnW and 189 nm/V for quasi-statics and resonant frequency actuation, respectively. This makes the fabricated cantilevers attractive for high-speed MEMS actuators.