Chemical recognition based on micromachined silicon cantilever array

Abstract

We report on the performance of a measurement system for the recognition of individual analytes and their binary mixtures which is based on a multiarray of four micromachined silicon cantivelers actuated at their resonance frequency. The cantilevers have been functionalized by organic polymers [polydimethylsiloxane (PDMS) and polyvinylpyridine (PVP)] and amorphous nitrogen-rich carbon nitride films. We found that the sensitivity and selectivity of the cantilevers coated with CNx films change according to the layer thickness. Our results show that the selected combination of sensitive layers ensures a wide range of specific, reversible and reproducible sensor responses upon exposure to methanol, 2-propanol, water and their binary mixtures. Further, it was found that the differences in recovery times of PDMS and CNx films after exposure to the two alcohols and their mixtures could be used especially for low analyte concentrations as a second characteristic in addition to the resonance frequency shift for the identification of individual components in the mixtures.

Chemical gas sensors based on calixarene-coated discontinuous gold films

“…12a and b) show that differences in sensor recovery time can also be used for identification of individual components in gaseous mixtures. We have previously discussed this aspect for microcantileverbased chemical sensors [7]. Likewise, concavity or convexity of the leading edge of the response curve was observed.…”

Bimaterial Microcantilevers as a Hybrid Sensing Platform

“…[226] Piezoresistive cantilever array coated with organic polymers have been reported to be capable of detecting methanol, 2-propanol, water and their binary mixtures to a wide range. [248] Two dimensional microcantilever arrays for multiplexed biomolecular analysis in liquids for DNA immobilization experiments have been successfully tested.…”

“…[110,226,248,249] An array of capacitively read-out micromachined cantilevers for measurement of adsorption-induced stress during exposure to hydrogen and mercury vapor was implemented as a handheld device including RF telemetry. [110] A polymer-coated complementary metal oxide semiconductor cantilever array for mass detection of volatile organic compounds in the dynamic mode has been tested with n-octane and toluene vapors.…”

Experimental measurement and model analysis of damping effect in nanoscale mechanical beam resonators in air

“…Such systems, besides serving as model systems for the study of fundamental electromechanical behavior at the nanoscale, also provide test beds for novel device and engineering development. [1][2][3] Significant advance has indeed been made in using such nanoscale mechanical resonance systems for the detection of biological entities and chemical species, [4][5][6] the sensing of small mass and force, [7][8][9][10] and the measurement of material properties and reological behaviors at the nanoscale. 1,2,[11][12][13] Individual nanostructures, made either through microfabrication or by chemical synthesis, are generally utilized as the key element, the cantilever beam in such systems, and the unique electromechanical, chemical, electronic, and other surface properties of these nanostructures are exploited.…”