Challenges and opportunities of chemiresistors based on microelectromechanical systems for chemical olfaction

Microelectromechanical-system (MEMS)-based semiconductor gas sensors are considered one of the fastest-growing, interdisciplinary high technologies during the post-Moore era. Modern advancements within this arena include wearable electronics, Internet of Things, and artificial brain-inspired intelligence, among other modalities, thus bringing opportunities to drive MEMS-based gas sensors with higher performance, lower costs, and wider applicability. However, the high demand for miniature and micropower sensors with unified processes on a single chip imposes great challenges. This review focuses on recent developments and pitfalls in MEMS-based micro- and nanoscale gas sensors and details future trends. We also cover the background of the topic, seminal efforts, current applications and challenges, and opportunities for next-generation systems.Agency for Science, Technology and Research (A*STAR)Ministry of Education (MOE)Submitted/Accepted versionThe authors gratefully acknowledge financial support from the National Natural Science Foundation of China (62074123), the PetroChina Innovation Foundation (2019D-5007-0410), the Singapore Agency for Science, Technology and Research (A*STAR) under the Manufacturing, Trade and Connectivity Individual Research Grant (M21K2c0105), and the Ministry of Education Singapore under its Academic Research Funds (RG3/21 and MOET2EP10120-0003)