Abstract: An acoustic resonator comprises a first electrode and second electrode comprising a plurality of sides. At least one of the sides of the second electrode comprises a cantilevered portion. A piezoelectric layer is disposed between the first and second electrodes. An electrical filter comprises an acoustic resonator.

Abstract: A thin film bulk acoustic resonator (FBAR) includes a first electrode stacked on a substrate over a cavity, a piezoelectric layer stacked on the first electrode, and a second electrode stacked on the piezoelectric layer. Multiple lateral features are formed on a surface of the second electrode, the lateral features including multiple stepped structures.

Abstract: A device includes: a first electrode having a first electrode thickness; a first acoustic propagation layer disposed on the first electrode, the first piezo-electric layer having a first acoustic propagation layer thickness; a second electrode having a second electrode thickness; a second piezo-electric layer disposed on the first electrode, the second piezo-electric layer having a second acoustic propagation layer thickness; and a third electrode having a third electrode thickness, wherein the second electrode thickness is between 1.15 and 1.8 times the first electrode thickness. The first and third electrode thicknesses may be equal to each other, and the first and second piezo-electric layer thicknesses may be equal to each other. The first and third electrodes may be connected together to provide two acoustic resonators in parallel with each other.

Abstract: An acoustic resonator comprises a substrate having a trench with lateral boundaries, a first electrode formed on the substrate over the trench and having lateral edges that are laterally offset from the lateral boundaries of the trench by a first distance, a first piezoelectric layer formed on the first electrode, a second electrode formed on the first piezoelectric layer and having edges that are laterally aligned inside the lateral boundaries of the trench, a second piezoelectric layer located on the second electrode, and a third electrode located on the second piezoelectric layer and having edges that are laterally offset from the edges of the second electrode.

Abstract: A sputtering target comprises an alloy of scandium and aluminum, wherein the alloy has a concentration of 3-10 at % scandium and 90-97 at % aluminum. The sputtering target can be used to produce a piezoelectric layer for an apparatus such as an acoustic resonator.

Abstract: An acoustic resonator structure comprises a first electrode disposed on a substrate, a piezoelectric layer disposed on the first electrode and comprising aluminum scandium nitride, a second electrode disposed on the piezoelectric layer, and a temperature compensation feature having a temperature coefficient offsetting at least a portion of a temperature coefficient of the piezoelectric layer, the first electrode, and the second electrode.

Abstract: An acoustic resonator comprises a first electrode and second electrode comprising a plurality of sides. At least one of the sides of the second electrode comprises a cantilevered portion. A piezoelectric layer is disposed between the first and second electrodes. A bridge disposed adjacent to one of the sides of the second electrode.

Abstract: A bulk acoustic wave (BAW) resonator, comprises: a first electrode; a second electrode comprising a plurality of sides. At least one of the sides comprises a cantilevered portion. The bulk acoustic wave (BAW) resonator also comprises a piezoelectric layer disposed between the first and second electrodes. The piezoelectric layer comprises a piezoelectric material doped with a plurality of rare earth elements, and the cantilevered portion extends above the piezoelectric layer. The bulk acoustic wave (BAW) resonator comprises a gap between the cantilevered portion and the piezoelectric layer.

Abstract: A bulk acoustic wave (BAW) resonator, comprises: a first electrode; a second electrode comprising a plurality of sides. At least one of the sides comprises a cantilevered portion. The bulk acoustic wave (BAW) resonator also comprises a piezoelectric layer disposed between the first and second electrodes. The piezoelectric layer comprises a piezoelectric material doped with a plurality of rare earth elements, and the cantilevered portion extends above the piezoelectric layer. The bulk acoustic wave (BAW) resonator comprises a gap between the cantilevered portion and the piezoelectric layer.

Abstract: A bulk acoustic wave (BAW) resonator structure includes a first electrode disposed over a substrate, a piezoelectric layer disposed over the first electrode and a second electrode disposed over the first piezoelectric layer. The piezoelectric layer is formed of a piezoelectric material doped with multiple rare earth elements for improving piezoelectric properties of the piezoelectric layer.

Abstract: A bulk acoustic wave (BAW) resonator structure includes a first electrode disposed over a substrate, a piezoelectric layer disposed over the first electrode and a second electrode disposed over the first piezoelectric layer. The piezoelectric layer is formed of a piezoelectric material doped with one of erbium or yittrium at an atomic percentage of greater than three for improving piezoelectric properties of the piezoelectric layer.

Abstract: A bulk acoustic wave (BAW) resonator device includes a bottom electrode on a substrate over one of a cavity and an acoustic reflector, a piezoelectric layer on the bottom electrode, and a top electrode on the piezoelectric layer. At one of the bottom electrode and the top electrode is a composite electrode having an integrated lateral feature, arranged between planar top and bottom surfaces of the composite electrode and configured to create a cut-off frequency mismatch.

Abstract: A bulk acoustic wave (BAW) resonator structure comprises a first electrode disposed over a substrate, a piezoelectric layer disposed over the first electrode, a second electrode disposed over the first piezoelectric layer, and a guard ring structure formed around a perimeter of an active region corresponding to an overlap of the first electrode, the first piezoelectric layer, and the second electrode.

Abstract: A stacked bulk acoustic resonator includes a first piezoelectric layer stacked on a first electrode, a second electrode stacked on the first piezoelectric layer; a second piezoelectric layer stacked on the second electrode, and a third electrode stacked on the second piezoelectric layer. The stacked bulk acoustic resonator further includes an inner raised region formed in an inner portion on a surface of at least one of the first, second and third electrodes, and an outer raised region formed along an outer perimeter on the surface of the at least one of the first, second or third electrodes. The outer raised region surrounds the inner raised region and defines a gap between the inner raised region and the outer raised region.

Abstract: A thin film bulk acoustic resonator (FBAR) includes a first electrode, a first piezoelectric layer having a first c-axis orientation and on the first electrode, a second piezoelectric layer having a second c-axis orientation over the first piezoelectric layer, and a second electrode on the second piezoelectric layer. The first and second piezoelectric layers are made of respective different piezoelectric materials. The FBAR can be set to have different resonance frequencies by selecting the first and second c-axis orientations to be respectively the same or different. The high and low frequency range of the FBAR can thus be extended.

Abstract: A thin film bulk acoustic resonator (FBAR) includes a first electrode stacked on a substrate over a cavity, a piezoelectric layer stacked on the first electrode, and a second electrode stacked on the piezoelectric layer. Multiple lateral features are formed on a surface of the second electrode, the lateral features including multiple stepped structures.

Abstract: An acoustic resonator comprises a substrate having a trench with lateral boundaries, a first electrode formed on the substrate over the trench and having lateral edges that are laterally offset from the lateral boundaries of the trench by a first distance, a first piezoelectric layer formed on the first electrode, a second electrode formed on the first piezoelectric layer and having edges that are laterally aligned inside the lateral boundaries of the trench, a second piezoelectric layer located on the second electrode, and a third electrode located on the second piezoelectric layer and having edges that are laterally offset from the edges of the second electrode.

Abstract: An acoustic resonator comprises (a) a substrate having atop surface and a bottom surface, a first end portion and an opposite, second end portion, and a body portion defined therebetween; (b) an acoustic mirror having a top surface and a bottom surface, a first end portion and an opposite, second end portion, and a body portion defined therebetween, wherein the bottom surface is formed on the top surface of the substrate; (c) a first electrode having a top surface and a bottom surface, a first end portion and an opposite, second end portion, and a body portion defined therebetween, wherein the bottom surface is formed on the top surface of the acoustic mirror; (d) a piezoelectric layer having a top surface and a bottom surface, a first end portion and an opposite, second end portion, and a body portion defined therebetween, wherein the bottom surface is formed on the top surface of the first electrode; and (e) a second electrode having a top surface and a bottom surface, a first end portion and an opposite, s

Abstract: A device includes: a first electrode having a first electrode thickness; a first acoustic propagation layer disposed on the first electrode, the first piezo-electric layer having a first acoustic propagation layer thickness; a second electrode having a second electrode thickness; a second piezo-electric layer disposed on the first electrode, the second piezo-electric layer having a second acoustic propagation layer thickness; and a third electrode having a third electrode thickness, wherein the second electrode thickness is between 1.15 and 1.8 times the first electrode thickness. The first and third electrode thicknesses may be equal to each other, and the first and second piezo-electric layer thicknesses may be equal to each other. The first and third electrodes may be connected together to provide two acoustic resonators in parallel with each other.

Abstract: A stacked bulk acoustic resonator includes a first piezoelectric layer stacked on a first electrode, a second electrode stacked on the first piezoelectric layer; a second piezoelectric layer stacked on the second electrode, and a third electrode stacked on the second piezoelectric layer. The stacked bulk acoustic resonator includes further includes an inner raised region formed in an inner portion on a surface of at least one of the first, second and third electrodes, and an outer raised region formed along an outer perimeter on the surface of the at least one of the first, second or third electrodes. The outer raised region surrounds the inner raised region and defines a gap between the inner raised region and the outer raised region.