Surface acoustic wave properties of La3Ta0.5Ga5.5O14 single crystals

The propagation characteristics of Rayleigh waves on a La3Ta0.5Ga5.5O14 (LT G) substrate were theoretically investigated fur all cuts and propagation d irections. The material constants, such as the elastic stiffness, piezoelec tric constants and their thermal coefficients, were measured by the resonan t and antiresonant frequency method. The existence of orientations with zer o-temperature coefficient of delay (TCD) was calculated by computer analysi s. The electromechanical coupling coefficient (k(2)) is about three times l arger than that of ST-cut quartz. The phase velocity is approximately 2690 m/s. These results indicate a large possibility for application to wide-han d intermediate-frequency surface acoustic wave (SAW) tilter devices.