A Novel SAW Humidity Sensor Based on Electrosprayed Polymerized Electrolyte Film

A novel humidity sensor with high sensitivity, short response time and excellent reproducibility was developed. The sensor utilized single-port surface acoustic wave resonator (SAWR) with high resonance frequency as basic component. The silicone-containing polyelectrolyte was electro sprayed onto SAWR surface to form humidity-sensitive film with micro/nano-scale. The experimental results showed that the humidity sensor made with the novel method has a wide detection range at least from 10% to 97% RH, a high sensitivity and up-to 1% RH measurement accuracy and a short response time less than 3s.