Three-Dimensional-Nanopatterned Resonant Silicon Microcantilevers for Gas Detection

This dissertation reports the breakthrough in designing and fabricating 3D nanopatterned piezoresistive-Si-microcantilever resonators for gas sensing applications. For the first time, 3D nanocomposites of inorganic nanostructures (Si nanofins, Si nanopillars and ZnO nanorods) and organic self-assembled monolayers have been successfully fabricated on microcantilevers. These 3D microcantilevers can work as self-actuating and self-reading out micro gravimetric sensors. High performance relative humidity sensing, and real time NO2 gas detection of ppbv level at room temperature have been realized and described in this thesis, indicating great opportunity for the development and mass production of extremely sensitive sensors for in situ assessment of body condition and medical diagnosis by respiration monitoring, as well as detecting of many chemical and explosive gases.