ABSTRACT
Sensors have a great inluence in many areas such as environmental monitoring, domestic safety, public security, and industrial quality control. Gas sensors are most commonly deployed to detect not only innocuous gases such as water and oxygen in automobiles but also life-threatening gases such as carbon monoxide (at home), chlorine (a low-cost weapon of mass destruction (WMD)), etc. The modern semiconductor industry relies very heavily on maintaining a safe work environment during manufacturing by employing a vast array of sensors capable of detecting gases such as phosphine,
hydrogen luorides, and hydrogen sulide. In addition, the need for detecting air-borne pathogens and potentially monitoring spread of contagious diseases remains at the forefront of modern gas sensor research. Due to this huge application range, the need for cheap, small, low-power-consuming and reliable solid-state gas sensors has grown over the years and has triggered an intense research activity worldwide to overcome metal oxide sensors drawbacks, summed up in improving the well-known “3S”: Sensitivity, Selectivity, and Stability [1].
