Comparison Between Conductometric and Layered SAW Hydrogen Gas Sensor

摘要

A comparison between the performance of conductometric and layered surface acoustic wave (SAW) hydrogen sensors is presented. Both sensor structures employ an R.F. magnetron sputtered tungsten trioxide (WO_3) thin film as a selective layer for hydrogen (H_2) sensing applications. The conductometric device is based on an alumina substrate, while the layered SAW device structure is fabricated on a 36°Y-cut, X-propagating LiTaO_3 substrate with a zinc oxide (ZnO) guiding layer. The sensors were investigated for different operational temperatures and various concentrations of H_2 in synthetic air.