Surface acoustic wave device and method of manufacturing same
AssigneeThomson-CSF
InventorGerard Coussot
Life of this patent
Estimating the term…
Abstract
The present invention relates to electromechanical devices for the transmission of surface acoustic waves between a launching transducer and a receiving transducer arranged upon the main face of a substrate. The transmission device in accordance with the invention comprises ground zones provided in order to scatter the vibrational energy of bulk waves propagating within the thickness of the substrate. The creation of the ground zones involves the use of a jet of sand directed on to the large faces of the substrate.
Claims5
Surface acoustic wave device comprising a piezo-electric wafer having two main faces opposite one another and two sets of interdigitated comb shaped electrodes lying on one of said main faces, said sets respectively forming a launching and a receiving transducer, said device further comprising on said one main face surface acoustic wave coupling means positioned between said transducers for causing the surface acoustic waves to follow within said one main face a path including a step, the other of said main faces comprising at least one ground zone facing at least one of said sets for scattering the bulk acoustic waves travelling across the thickness of said piezo-electric wafer.
Dependencies are inferred from the claim text.