Highly Sensitive Metal-Oxide Gas Sensor Using Thermal Doping Technique for High Device Uniformity

This paper presents a uniform catalyst doping technique to enhance the sensitivity and reproducibility of metal-oxide gas sensors. Gold (Au) catalysts were deposited onto tin oxide (SnO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>) nanowires and uniformly diffused into the sensing layer through thermal annealing. The process employs semiconductor-compatible, top-down fabrication methods, enabling scalability and high device uniformity. Experimental results show less than 10% deviation in base resistance across batches and more than a sevenfold increase in sensitivity to carbon monoxide (CO) at 30 ppm.