SAW and QMB for chemical sensing

We aimed to compare the properties of high frequency, highly sensitive surface acoustic wave (SAW)-resonators and the more robust quartz micro balances (QMB) in chemical sensing. The sensitivities of both transducers to organic solvent vapors were determined. The correlation between sensor effects and resonant frequencies of the devices was checked previously using molecular cavities as sensor materials. Additionally the potential of another means of sensor material synthesis compatible with fabrication processes was tested, namely the procedure of molecular imprinting. Analyte-adapted cavities can be generated by a polymerization process in presence of the analyte to be. An imprint of the latter is left behind in the polymer after removal of the template molecule. In this way sensitive and selective coatings can easily be generated. They are thus suitable for organic solvent vapor detection devices.