Integrated metallic gauge in a piezoelectric cantilever

In this study, a self-sensitive piezoelectric cantilever with a new design for sensing is presented. Micro-cantilevers were actuated by a 120 nm-thick Lead Zirconate Titanate Oxide (PZT) layer. Detection was done by measuring the resistance of a metallic gauge integrated on the surface of the micro-piezoelectric cantilevers. Some metallic gauges were embedded in a Wheatstone bridge to improve the measured resistance accuracy. Devices with direct resistance measurement were also realized. Gauge resistance responses were compared with an optical measurement by a White Light Interferometer. By biasing the PZT between −5 V and 5 V, cyclic deflection of the cantilever was detected with both optical and metallic gauge resistance systems. The two measurements fit. This self-sensitive piezoelectric cantilever can be used for fatigue test with packaged devices.