Parametric model of a polymeric chemoresistor for use in smart sensor design and simulation

Abstract A novel parametric model of a polymeric chemoresistor is proposed for application in the design and simulation of smart gas sensors. The model has been implemented using Cadence™ software and enables the simulation of both the static and dynamic response of a chemoresistor to a mixture of different gases. It also takes into account parametrically the effects of ambient temperature, humidity and sensor noise. The layout design and a schematic symbol have also been generated in Cadence -thus creating a resistive polymeric cell that can be used in the general design of smart ASIC based systems. The top cell comprises several sub-cells allowing versatility and adaptability in implementation through its modular structure. By changing the values of the simulation parameters and/or the mathematical model of the sub-cell that evaluates the gas sensor response, it is possible to extend its application to the design and simulation of chemoresistors in different configurations and with different gas sensitive materials. Here we illustrate our model in the design and simulation of resistive sensors employing carbon-black polymer composite films as the class of gas sensitive material.

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