A CMOS sensor array IC for Van der Waals enhanced MOSFET and Taguchi type sensors

A CMOS sensor array IC capable of performing fluctuation enhanced sensing for two different chemical sensing devices has been designed. The targeted sensing devices are the novel Van der Waals force enhanced MOSFET for gas and nano-particle detection and sputtered ZnO thin films as Taguchi-type sensors for gas detection. The sensor output contains information in the dynamic stochastic fluctuations around the mean value which prove useful for detection of sub-ppm concentrations of gaseous molecules. This paper discusses an implementation of fluctuation-enhanced sensing on silicon. The CMOS sensor IC consists of a low-noise transimpedance amplifier filter bank and output buffers. The circuits are all designed to operate at temperatures as high as 200/spl deg/C with low leakage currents. The overall CMOS system on chip exhibited enhanced selectivity and accuracy in providing unique signatures for gas detection.