Highly Sensitive AIN Surface Acoustic Wave Humidity Sensor Based on Uniform Graphene Oxide Thin Film Formed by Surface Tension

Abstract

This paper proposes a high performance surface acoustic wave (SAW) humidity sensor based on uniform thin graphene oxide film. A simple and convenient film-forming process is used to prepare the GO film repeatedly and steadily, which utilizing the surface tension of GO solution. With the help of the uniform GO film, the sensor shows a high sensitivity (25.3 kHz/%RH) in a wide humidity detection range from 10%RH to 90 ^% RH with very little humidity hysteresis (less than 1%RH). Good reversibility, excellent short term repeatability and stability of the sensor are obtained. Moreover, the sensor also shows fast response and recovery time of 10 and 7 seconds respectively.