Interface acoustic wave device made of lithium tantalate

摘要

The invention relates to interface acoustic wave components made of lithium tantalate. In the case in which the two substrates making up the filter have the same cut and the same crystal orientation, the invention gives the best cut angles in particular for optimizing the electromechanical coupling coefficient that determines the final performance characteristics of the component produced. Curves giving the variations of the coupling coefficient and the attenuation as a function of the cut angles and of the direction of propagation are provided. The values of the main acoustic characteristics of the component for these optimum cut angles are also given. The applications of this type of device are, on the one hand, uses as a passive component such a resonator or a filter or a delay line, or as an integrated device, either in a measurement chain or in an array of devices operating according to the principle of recognition of the device by a phase code.