Articles techniques et présentations

In this paper, we discuss a simplified finite element method simulation of surface acoustic wave (SAW) delay line hydrogen sensor using COMSOL Multiphysics.  A delay line SAW sensor consists of a transmitting interdigital transducer (IDT) and a receiving IDT separated by a few wavelengths. In this work, the number of degrees of freedom to solve for the SAW delay line sensor model is minimized by providing periodic boundary conditions to the transmitting IDT, which is a one finger structure. Further, a palladium thin film is coated over the delay line. The palladium film transforms to palladium hydride in the presence of hydrogen. This change in palladium properties is provided to the assumed thin film over the delay line. The time domain analysis of the SAW sensor with and without the presence of hydrogen is performed and change in velocity of the SAW is observed.