TiO2 based surface acoustic wave gas sensor with modified electrode dimensions for enhanced H2 sensing application

The design and optimization of nanostructure-based surface acoustic wave (SAW) gas sensor is analyzed based on TiO2 sensing layer and modified electrode dimensions. The sensitivity of the gas sensor depends upon the type of sensing layer used and active surface area obtained by varying the aspect ratio. The performance of the sensor is observed from 0.1ppm to 100ppm concentration of hydrogen gas with respect to output displacement. The displacement of the sensor increases with the increase in concentration. The characteristic of the sensor is also studied by varying input and output inters digited transducers' (IDT) height from 0.05 mu m to 0.5 mu m. The nanostructured TiO2 based sensor has shown increased total displacement and frequency shift of the device resulting enhanced sensitivity. At 0.05 mu m IDT height the displacement is found to be a maximum. The operating frequency is considered to be 44 Mhz. Finite Element Modeling (FEM) is used for analysis of the sensor. Simulation is done in software named COMSOL Multiphysics to ensure the enhanced performance of the mechanically engineered surface-based (nanorod) SAW gas sensor.