Design and Realization of a Planar Interdigital Microsensor for Biological Medium Characterization

International audienceIn this work, we present the design of a planar interdigital microsensor for the characterization of biological mediums by impedance spectroscopy. We propose a theoretical optimization of the geometrical parameters of this sensor. The optimization allows to extend the measurement frequency range by reducing the polarization effect which is manifested by a double layer (DL). We present also a new method for a planar interdigital transducer to determine the parameters (relative permittivity, capacitance) of the double layer (DL) on the surface of the electrode loaded by a biological medium. The CoventorWare® software was used to simulate the model design of interdigital transducer in three dimensions (3D). The simulation results are coherent with the method proposed. Therefore, this method can be used to determine the parameters of double layers of a planar interdigital sensor in order to match its frequency band to the intented application