Investigation of Highly Sensitive and Linearly Responsive SAW Based Gas Sensor for Better N2 Detection

Surface acoustic wave sensors are becoming more and more essential in research. The research has advanced in such a way that SAW sensors are now used in many different fields. The application areas of SAW sensor include gas sensing, biosensor, measurement of many physical parameters like humidity, pressure, temperature and torque. In this study, the SAW sensor is presented as a nitrogen gas sensor. Nanomaterials are introduced to a conventional SAW sensor to strengthen the sensor's performance. The most frequently used nano - materials for applications in gas detection is ZnO. Comsol Multiphysics is used to design a 2D SAW-based gas sensor using ZnO as the sensing material. Finite element analysis (FEA) is used in sensor characterization. Testing is done to determine whether nitrogen gas is present or not in the sensor. The sensor's sensitivity varies depending on whether there is gas present or not while operating at the same frequency. The sensor's frequency range is 3 MHz. Nitrogen gas is present in concentrations varying from 10 ppm to hundreds of ppm. With a rise in concentration, the sensor showed excellent linearity.