Coupling nanowire chemiresistors with MEMS microhotplate gas sensing platforms

Abstract

Recent advances in nanotechnology have yielded materials and structures that offer great potential for improving the sensitivity, selectivity, stability, and speed of next-generation chemical gas sensors. To fabricate practical devices, the “bottom-up” approach of producing nanoscale sensing elements must be integrated with the “top-down” methodology currently dominating microtechnology. In this letter, the authors illustrate this approach by coupling a single-crystal SnO2 nanowire sensing element with a microhotplate gas sensor platform. The sensing results obtained using this prototype sensor demonstrate encouraging performance aspects including reduced operating temperature, reduced power consumption, good stability, and enhanced sensitivity.