Modal Interaction for Enhanced Gas Sensing in NEMS Using Roof-Tilting Mechanism

This paper introduces a highly sensitive and stable Nanoelectromechanical Systems (NEMS) sensor that overcomes the challenges faced by conventional sensors in detecting low gas concentrations while minimizing fluctuations caused by temperature variations, excitation amplitude shifts, and Electromagnetic Interference (EMI). By leveraging a slope-based detection mechanism driven by modal interactions, the sensor effectively mitigates the impact of slow excitation amplitude variations. The design features a nano cantilever, a 200 nm-thick Zinc Oxide (ZnO) layer, which serves as both the structural and sensing element. This configuration enables precise angle tilts corresponding to specific gas concentrations, achieving detection sensitivity beyond the capabilities of traditional sensors. Furthermore, the proposed sensor exhibits high linearity over a broad range of mass perturbations and maintains robust performance under varying environmental temperatures, making it well-suited for diverse engineering applications.