Multiparametric light-assisted silicon device transduction of molecular recognition events

The contemporaneous measurement of different physical properties of a chemical sensing layer is expected to provide a general increase of selectivity. The application of this concept generally requires the use of multiple devices. In this paper, the measurement of optical and electric properties of one sensing layer with a single device is presented. The surface potential and optical sensitivities of a field effect transistor are utilized to develop a multi-parametric sensor able to evaluate, at the same time, changes in the electric dipole and in the optical absorbance of a metalloporphyrin layer. The properties of the multiparametric approach are illustrated with an example aimed at recognizing different gases and vapours.