The fabrication of scalable multi-sensor arrays using standard CMOS technology [chemical sensors]

This paper describes an approach for fabricating MOSFET-based scalable multi-sensor arrays in an unmodified standard CMOS process. The circuit design uses novel multiplexing to make a differential potentiometric measurement in each cell of the array. All signal processing is performed in-situ and all readout circuitry is located onchip. Various chemical sensors can be formed with minimal post-processing using standard photolithographic techniques. An implementation of a single-chip 2×2 array is presented along with initial results and discussion of the device characteristics.