Nerve gas sensor using film bulk acoustic resonator coated with poly (vinylidene fluoride)

A nerve gas sensor based on a film bulk acoustic resonator is presented. The resonator consists of a piezoelectric Au/AlN/Mo stack and a Bragg reflector and has a working resonance near 2.1 GHz. A poly (vinylidene fluoride) layer is coated on the top electrode as a specific chemical recognition. The sensor can yield a rapid, sensitive, reversible and reproducible response to the stimulant of nerve agent. The gas sensitivity is as high as 80 kHz/ppm, which is orders of magnitude higher than that of quartz crystal microbalance. The advantages of this sensor, including the sample fabrication process, ease of detection method, rapid response and high sensitivity, make this promising in the early alarm of nerve agents.