An improved sensitivity AlN microcantilever humidity sensor using interdigital transducers actuated very high resonant mode and graphene oxide sensing layer

This paper presents a novel interdigital transducers (IDTs) actuated AlN microcantilever humidity sensor coated with graphene oxide (GO) thin film as sensing layer. Utilizing the IDTs, the microcantilever can operate at very high resonant mode to achieve significant high sensitivity. Compared with the normal electrodes actuated microcantilever sensor with the same size, the sensitivity of the IDTs actuated microcantilever sensor is increased by more than 10 times. Moreover, very little hysteresis, excellent short term repeatability, fast response and short recovery times (less than 10 s) of the sensors are obtained.