M.F. Ibrahim, F. Elsayed, Y.H. Ghallab, W. Badawy
This research work presents a new implementation of the CMOS electric-field sensor, titled as Differential Electric Field Sensitive Field Effect Transistor (DeFET). The DeFET is successfully used in detection of small partials and it is a suitable candidate to be used in biochemical and environmental applications. The developed implementation of the DeFET provides an improved sensitivity, thus it can be used to detect tiny particles in the range of nano meter scale. The direct application of the proposed sensor is the air pollution and environmental detection. The chip is implemented using 180 nm CMOS technology; it contains both the actuation and sensing parts. The sensors are distributed in two different sets (uniform and nonuniform arrays), each sets contains 8 DeFET sensors, one set has uniform sensors, i.e. the sensors have the same dimension, and the other set has non-uniform sensors which have different dimensions. With a constant electric field profile, this configuration will give directly the improvement that is obtained with respect to the sensitivity.