Transducer structure for source suppression in saw filter devices

A transducer structure for a surface acoustic wave device, formed on an acoustic wave propagating substrate, the transducer structure being configured for coupling to an electrical load and/or source, comprising:

• a pair of inter-digitated comb electrodes formed on the acoustic wave propagating substrate, wherein the pair of inter-digitated comb electrodes comprises neighboring electrode means belonging to different comb electrodes and having a pitch p being defined as an edge-to-edge electrode means distance between two neighboring electrode means, the pitch p satisfying a Bragg condition given by p=λ/2,λ being an operating acoustic wavelength of the transducer structure, and wherein the electrode means all have a same geometry;
• wherein the pair of inter-digitated comb electrodes comprises at least one region in which two or more neighboring electrode means belong to the same comb electrode while having an edge-to-edge distance to each other corresponding to the pitch p and having the same geometry;
• and
• wherein the acoustic wave propagating substrate is a composite substrate comprising at least a base substrate of a first material and a top layer of a piezoelectric material with a thickness being more than one wavelength of the operating acoustic wavelength.