Modeling Noise and Stability of Affinity-Based MEMS, NEMS and NOEMS Sensors of Ternary Gas Mixtures

We address noise and stability of adsorption-based sensing of ternary gas mixtures in affinity-based MEMS, NEMS and NOEMS sensors. We investigate mechanisms of such chemical sensing in diverse industrial environments where ternary gas mixtures are of importance. in all existing sensing devices signal fluctuations determine their ultimate performance, and in affinity-based nanodevices the prevailing noise is caused by adsorption and desorption of different species at the sensor surface. We consider analytically and numerically detection of three-component gas mixtures. We present results obtained by applying the conventional method for assessing stability of chemical reactions to three component monolayer adsorption. Gas molecules modeling as spherical particles is suitable for applying any model regarding population dynamics, but taking molecular dimension and orientation into account is more realistic. Noise analysis in time and frequency domain is performed for two different classes of ultrahigh sensitivity adsorption based gas sensors: (nano) plasmonic sensors (refractometric devices) and MEMS/NEMS resonator-based devices.