SSBW to PSAW conversion in SAW devices using heavy mechanical loading.

The development of efficient computation tools based on mixed analytical and numerical calculation approaches allows precise descriptions and characterizations of surface acoustic waves (SAW) propagation, taking into account realistic electrical and mechanical boundary conditions. As an example, suppression of the leaky SAW, also called pseudo SAW (PSAW), attenuation has been predicted using such tools allowing to explain experimental occurrences for SAW devices on YX cut lithium niobate and lithium tantalate with thick aluminum strip gratings (6% < h/lambda < 10%). In this work, such a theoretical model is used to analyze the evolution of surface waves on standard YX lithium tantalate cuts versus aluminum strip height.