A1.2 - The Effect of Water Molecules on the Propagation of SAW on a Free 128° Y-X Lithium Niobate Substrate with Masked IDTs

A surface acoustic wave (SAW) traveling along the free surface of a piezoelectric substrate can interact with water molecules in the air/nitrogen, especially at higher concentrations, even without the use of special sorption membranes.This phenomenon may be related to the interaction of the electric dipole moment of water molecules and the electric field associated with the propagating surface wave.To more accurately distinguish whether the observed interactions result from the above phenomenon or are the result of an interdigital transducers (IDTs) electrical capacity disturbance, for example, tests were designed and conducted with masked IDTs using SiO 2 layers.In this way, the effect of water vapor on the IDTs was eliminated.The observed interactions are the result of only dipole interactions between water molecules and the free area with SAW electric field.