Flow Compensated Gas Sensing Array for Improved Performances in Breath-Analysis Applications

Metal-oxide gas sensors have great potential for emerging applications, including breath analysis due to their small form factor, low cost, and low power, which enables integration in consumer electronics, such as smartphone accessories, wearables, and, in the future, smartwatches and phones. Acetone concentration in breath is an important biomarker for well-being and biomedical applications, such as weight loss and ketoacidosis monitoring. In this article, we present a monolithically integrated array of gas sensors combined with a flow sensor in order to provide better quantification of acetone. In particular, this work demonstrates improvement in the acetone selectivity thanks to the combination of three different metal oxides and the ability to compensate with the flow variation.