Suppression Of Spurious Modes On Lgs With Euler Angle Of (0 Degrees, 22 Degrees, 30 Degrees)

Langasite with Euler angle of (0 degrees, 22 degrees, 30 degrees) was regarded as suitable substrate for high temperature pressure sensor in previous research. Nevertheless, the spurious modes on this cut restrict its performance. In order to suppress the spurious modes, two different structures, a triple-electrodes one and a grooved one, are proposed. Simulation results are utilized to evaluate and optimize the two constructions. The triple-electrodes one modifies the distribution of the acoustic field. With well designed parameters, spurious modes can be suppressed electrically. While the grooved one shifts the spurious modes far away from the main mode. Spurious modes can be suppressed when their resonance frequencies are outside of the stop band of the reflecting grooves. Both structures are proved effective in spurious modes suppression.