Organic Vapour Discrimination Using Sorption Sensitive Chemocapacitor Arrays
An interdigital chemocapacitor (IDC) sensor array has been developed to discriminate organic vapour samples with pure organics and mixtures. Sensors were coated with diverse polymers (PEUT, PDMS and modified PDMS). Dedicated signal conditioning circuits were developed with a reduced S/N ratio enabling measurement of capacitance changes as low as 0.07 fF. A new sampling technique was also developed to improve isobaric sampling conditions on the sensors chamber. Linear techniques such as Principal Component Analysis (PCA) for discrimination between the different samples were sucessfully applied. As far as we know, this is the first time that an array of interdigital chemocapacitors is used for organic vapour discrimination.
Paula Maria Vilarinho
R. Igreja, C.J. Dias, "Organic Vapour Discrimination Using Sorption Sensitive Chemocapacitor Arrays ", Materials Science Forum, Vols. 514-516, pp. 1064-1067, 2006