CMOS Single Chip Gas Detection Systems — Part I

Abstract

AbstractThe current trend to control indoor air‐quality and to monitor environmental pollution has created a strong demand for miniaturized and inexpensive gas sensors for volatile organic compounds (VOCs). Gas sensor arrays based on industrial CMOS‐processes combined with post‐CMOS micromachining (CMOS MEMS) are a promising approach to low‐cost sensor devices. In this article, the state of research of CMOS‐based gas sensor systems is reviewed, and a platform technology is described, which provides the possibility of monolithically integrating several different transducers on a single chip. A design environment, batch‐fabrication processes, and fast testing procedures were developed to realize an example single‐chip gas detection system. The chip includes the transducers, their biasing circuitry, reference elements, a digital interface, and a temperature sensor. The three polymer‐based transducers and their interface electronics will be detailed in the second part of this article [1].