Abstract: Disclosed embodiments include a surface acoustic wave device having electrode period, electrode width, and/or ratio of electrode width to electrode period varied in a prescribed manner.

Abstract: Disclosed embodiments include a surface acoustic wave device having electrode period, electrode width, and/or ratio of electrode width to electrode period varied in a prescribed manner.

Abstract: An acoustic wave device operable as a piston mode wave guide includes electrodes forming an interdigital transducer on a surface of the piezoelectric substrate, wherein each of the plurality of electrodes is defined as having a transversely extending center region and transversely opposing edge regions for guiding an acoustic wave longitudinally through the transducer. A Silicon Oxide overcoat covers the transducer and a Silicon Nitride layer covers the Silicon Oxide overcoat within only the center and edge regions. The thickness of the Silicon Nitride layer is sufficient for providing a frequency modification to the acoustic wave within the center region and is optimized with a positioning of a Titanium strip within each of the opposing edge regions. The Titanium strip reduces the acoustic wave velocity within the edge regions with the velocity in the edge regions being less than the wave velocity within the transducer center region.

Abstract: An acoustic wave device operable as a piston mode wave guide includes electrodes forming an interdigital transducer on a surface of the piezoelectric substrate, wherein each of the plurality of electrodes is defined as having a transversely extending center region and transversely opposing edge regions for guiding an acoustic wave longitudinally through the transducer. A Silicon Oxide overcoat covers the transducer and a Silicon Nitride layer covers the Silicon Oxide overcoat within only the center and edge regions. The thickness of the Silicon Nitride layer is sufficient for providing a frequency modification to the acoustic wave within the center region and is optimized with a positioning of a Titanium strip within each of the opposing edge regions. The Titanium strip reduces the acoustic wave velocity within the edge regions with the velocity in the edge regions being less than the wave velocity within the transducer center region.

Abstract: Improved coupling coefficients and desirable filter characteristics are exhibited in a SAW filter including an electrode pattern deposited on a piezoelectric substrate bonded directly to an anti-reflective layer, wherein the anti-reflective layer is bonded to a carrier through an adhesive layer such that a preselected thickness of the anti-reflective layer is sufficient for enhancing an acoustic match between the piezoelectric substrate and the adhesive layer.

Abstract: An interdigital transducer includes an edge gap length between ends of electrodes and the opposing busbar increased sufficiently for reducing or even eliminating tunneling effects through the gap. As a result, a wave velocity of the acoustic wave within the longitudinally extending edge regions is less than the wave velocity within the transducer center region, and the wave velocity within the opposing gap regions is greater than a velocity in the transducer center region, thus an essentially flat propagation mode results within the aperture of the transducer. A SAW transducer or a SAW resonator on a high coupling substrate will thus guide the energy in the transducer region without a need for apodization. Higher equivalent coupling factors as well as lower losses are obtained.

Abstract: An acoustic wave device includes electrodes carried on a surface of a piezoelectric material and an array of reflective obstacles such that elastic energy resulting from a piezoelectric effect is preferentially directed along a primary wave propagation path. The array of reflective obstacles are positioned generally parallel to the surface of the piezoelectric material and redirect acoustic waves typically reflected in other than a desirable direction to along a desired direction generally along the primary propagation path. The obstacles improve performance for SAW and BAW devices by effecting reflected energy and suppressing spurious modes.

Abstract: An interdigital transducer includes an edge gap length between ends of electrodes and the opposing busbar increased sufficiently for reducing or even eliminating tunneling effects through the gap. As a result, a wave velocity of the acoustic wave within the longitudinally extending edge regions is less than the wave velocity within the transducer center region, and the wave velocity within the opposing gap regions is greater than a velocity in the transducer center region, thus an essentially flat propagation mode results within the aperture of the transducer. A SAW transducer or a SAW resonator on a high coupling substrate will thus guide the energy in the transducer region without a need for apodization. Higher equivalent coupling factors as well as lower losses are obtained.