Stress, temperature and pressure behavior of SAW on langasite plates

Abstract

Langasite is a new piezoelectric material for high temperature sensor applications. This material possesses higher pressure sensitivity for SAW than that in alpha-quartz crystal. There are also cuts with extremely low sensitivity to pressure, all-round force compressing and change a temperature of langasite plates. In this work a detailed analysis of sensitivity of SAW resonator on the surface of langasite plates to pressure loading, temperature change and all-round force compressing of circle plate are presented. The influence of external static forces on the SAW velocity is computed in a case of circular plates (membranes). Pressure and radial in-plane stress sensitivities of the SAW velocity at any point on the surface of thin membrane as a function of langasite crystal anisotropy are presented by sensitivity contour mapping from two independent variables: direction of the SAW propagation and cut angles of langasite substrate.