Active-matrix monolithic gas sensor array based on MoS2 thin-film transistors

Highly sensitive and system integrable gas sensors play a significant role in industry and daily life, and MoS2 has emerged as one of the most promising two-dimensional nanomaterials for gas sensor technology. In this study, we demonstrate a scalable and monolithically integrated active-matrix gas sensor array based on large-area bilayer MoS2 films synthesized via two-successive steps: radio-frequency magnetron sputtering and thermal sulfurization. The fabricated thin-film transistors exhibit consistent electrical performance over a few centimeters area and resulting gas sensors detect NO2 with ultra-high sensitivity across a wide detection range, from 1 to 256 ppm. This is due to the abundant grain boundaries of the sputtered MoS2 channel, which perform as active sites for absorption of NO2 gas molecules. The demonstrated active-matrix gas sensor arrays display good switching capabilities and are anticipated to be readily integrated with additional circuitry for different gas sensing and monitoring applications. Sensitive and scalable gas sensors are essential in daily life air-quality monitoring. Here, a monolithically integrated gas sensing circuit based on two-step-grown polycrystalline MoS2 films is fabricated, showing good switching and NO2 gas sensing response in a wide detection range of 1 to 256 ppm.