Wafer-Level Patterning of SnO Nanosheets for MEMS Gas Sensors

Abstract

In the past few decades, gas sensitive nanomaterials are usually deposited on specific area of the wafer by drop-casting or inkjet printing for application in gas sensor fabrication. However, wafer-level patterning of sensing materials with satisfactory reproducibility still encounters challenge. In this letter, we propose a facile ‘top-down’ strategy to manufacture wafer-scale gas sensing chips with high-throughput by photolithography using a well-mixed photoresist-nanomaterial suspension, followed by calcination. The fabricated gas sensors based on the proposed approach yield excellent reproducibility and uniformity of sensing response to ethanol detection with a relative standard deviation (RSD) <4.5 %, suggesting promising application for high-volume production of MEMS compatible gas sensors.