Dummy device-based feedthrough cancellation for PZT on Silicon microcantilever for viscosity sensing

This abstract reports a thin film Lead Zirconate Titanate (PZT) on a Silicon-On-Insulator (SOI) microcantilever device as a fluid dynamic-viscosity $\left(\eta_{{fluid }}\right)$ sensor. It uses identical compensation (dummy) device based common drive and differential sensing to eliminate parasitic feedthrough. We experimentally demonstrate feedthrough cancellation and signal-to-background (SBR) ratio increase $(\gt10 \mathrm{~dB})$ in the microcantilever device’s second-flexural mode. Electrical characterization of the microcantilever is performed on different concentrations of glycerol-water solutions over a wide viscosity range of $0.78-6.15 \mathrm{cP}$.