Miniaturized thermal acoustic gas sensor based on a CMOS microhotplate and MEMS microphone

Richard Hopper; Daniel Popa; Florin Udrea; Syed Zeeshan Ali; Phillip Stanley-Marbell

doi:10.1038/s41598-022-05613-0

Miniaturized thermal acoustic gas sensor based on a CMOS microhotplate and MEMS microphone

Sci Rep. 2022 Feb 1;12(1):1690. doi: 10.1038/s41598-022-05613-0.

Authors

Richard Hopper¹, Daniel Popa², Florin Udrea², Syed Zeeshan Ali³, Phillip Stanley-Marbell²

Affiliations

¹ Department of Engineering, University of Cambridge, Cambridge, CB3 0FA, UK. rhh39@cam.ac.uk.
² Department of Engineering, University of Cambridge, Cambridge, CB3 0FA, UK.
³ Flusso Limited, Cambridge, CB4 0DL, UK.

Abstract

We present a miniaturised thermal acoustic gas sensor, fabricated using a CMOS microhotplate and MEMS microphone. The sensing mechanism is based on the detection of changes in the thermal acoustic conversion efficiency which is dependent on the physical properties of the gas. An active sensing element, consisting of a MEMS microphone, is used to detect the target gas while a reference element is used for acoustic noise compensation. Compared to current photoacoustic gas sensors, our sensor requires neither the use of gas-encapsulated microphones, nor that of optical filters. In addition, it has all the benefits of CMOS technology, including production scalability, low cost and miniaturization. Here we demonstrate its application for CO[Formula: see text] gas detection. The sensor could be used for gas leak detection, for example, in an industrial plant.

Publication types

Research Support, Non-U.S. Gov't