EXCITABLE PIEZOELECTRIC EPITAXIAL STRUCTURE AND ELECTRONIC DEVICE FOR THE GENERATION OF SURFACE ACOUSTIC WAVES THEREIN

摘要

An epitaxial structure in which a constraint imposed by forced epitaxy causes an increase in the piezoelectric effect of a group of layers. The structure which provides this effect utilizes a semi-insulating substrate made from a first material on which is deposited by forced epitaxy a layer of a second material, the two materials are in crystalline mesh parameter disharmony, which creates in said layer a constraint increasing its piezoelectricity. On the constrained layer are deposited two groups of alternated "deforming" and "deformed" layers of the two materials. The thickness of the structure is sufficient to allow propagation of the surface waves. The advantage of this structure is that it allows two transducers such as transistors to be integrated on or at the side of this structure.