Abstract: A method of fabricating a rare-earth element doped piezoelectric material having a first component, a second component and the rare-earth element. The method includes: providing a substrate; initially flowing hydrogen over the substrate; after the initially flowing of the hydrogen over the substrate, flowing the first component to form the rare-earth element doped piezoelectric material over a surface of a target, the target comprising the rare-earth metal in a certain atomic percentage; and sputtering the rare-earth element doped piezoelectric material from the target on the substrate.

Abstract: A surface acoustic wave (SAW) resonator structure includes a substrate, a piezoelectric layer disposed on the substrate, and an interdigital transducer (IDT) electrode disposed over the piezoelectric layer. The IDT electrode includes multiple busbars and multiple electrode fingers extending from each busbar, where the electrode fingers are configured to generate surface acoustic waves in the piezoelectric layer. The SAW resonator structure further includes dielectric material disposed between the piezoelectric layer and at least at portion of the IDT. The dielectric material may be positioned below tips of the electrode fingers, thereby mass-loading the electrode fingers.

Abstract: A bulk acoustic wave (BAW) 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. A bridge is formed within the piezoelectric layer, where the bridge is surrounded by piezoelectric material of the piezoelectric layer.

Abstract: In accordance with a representative embodiment, a method, comprises: providing a substrate; forming a first piezoelectric layer having a compression-negative (CN) polarity over the substrate; and forming a second piezoelectric layer having a compression-positive (CP) over the substrate and adjacent to the first piezoelectric layer.

Abstract: In a representative embodiment, a bulk acoustic wave (BAW) resonator structure comprises: a first electrode disposed over a substrate; a first piezoelectric layer disposed over the first electrode; a second electrode disposed over the first piezoelectric layer, wherein c-axis orientations of crystals of the first piezoelectric layer are substantially aligned with one another; a second piezoelectric layer disposed over the second electrode; a non-piezoelectric layer; and a third electrode disposed over the second piezoelectric layer.

Abstract: In a representative embodiment, a bulk acoustic wave (BAW) resonator structure comprises: a first electrode disposed over a substrate; a first piezoelectric layer disposed over the first electrode; a second electrode disposed over the first piezoelectric layer, wherein c-axis orientations of crystals of the first piezoelectric layer are substantially aligned with one another; a second piezoelectric layer disposed over the second electrode; a non-piezoelectric layer; and a third electrode disposed over the second piezoelectric layer.

Abstract: A bulk acoustic wave (BAW) 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. A bridge is formed within the piezoelectric layer, where the bridge is surrounded by piezoelectric material of the piezoelectric layer.

Abstract: In accordance with a representative embodiment, a method, comprises: providing a substrate; forming a first piezoelectric layer having a compression-negative (CN) polarity over the substrate; and forming a second piezoelectric layer having a compression-positive (CP) over the substrate and adjacent to the first piezoelectric layer.

Abstract: An apparatus includes a stacked crystal filter and a bulk acoustic wave resonator, which are acoustically coupled.

Abstract: A bulk acoustic wave device includes a first electrode, a second electrode, a piezoelectric layer arranged between the first and second electrodes and a semiconductor layer arranged between the first and second electrodes. The semiconductor layer is electrically isolated from the first electrode.

Abstract: A method for manufacturing a filter device is provided. The filter device comprises a coupled resonator at a first site, a shunt resonator at a second site and a series resonator at a third site, the coupled resonator comprising a first and a second resonator. The method comprising a step of providing a substrate with a piezoelectric layer sandwiched between a first electrode and a first part of a second electrode at the first site and the second site, the piezoelectric layer sandwiched between the first electrode and a second part of the second electrode at the third site. The method further comprising the step of forming a coupling layer on the second electrode, the step of forming a further piezoelectric layer sandwiched between a further first electrode and a further second electrode at the third site and the step of removing the coupling layer at the second and third sites.

Abstract: A thin-film BAW filter has at least one CRF section and at least one ladder or grating filter section, with the CRF section having at least two coupled resonators, with the CRF section and the ladder or grating filter section being integrated on a common substrate, in order to produce a thin-film BAW filter. In a method for production of a thin-film BAW filter, having at least one CRF section and at least one ladder or grating filter section, the CRF section has at least two coupled resonators and the CRF section and the ladder or grating filter section are integrated on a common substrate.

Abstract: A bulk acoustic wave device includes first and second resonators, which are acoustically coupled and electrically connected in parallel.

Abstract: An apparatus includes a first bulk acoustic wave (BAW) device including a first impedance and a second BAW device including a second impedance, wherein the first and second impedances are different and the first and second BAW devices are acoustically coupled.

Abstract: A bulk acoustic wave device includes a first electrode, a second electrode, a piezoelectric layer arranged between the first and second electrodes and a semiconductor layer arranged between the first and second electrodes. The semiconductor layer is electrically isolated from the first electrode.

Abstract: An apparatus includes a first bulk acoustic wave (BAW) device including a first impedance and a second BAW device including a second impedance, wherein the first and second impedances are different and the first and second BAW devices are acoustically coupled.

Abstract: An apparatus includes a stacked crystal filter and a bulk acoustic wave resonator, which are acoustically coupled.

Abstract: An acoustic resonator is described, the acoustic resonator comprising a stack of a first and a second piezoelectric body, wherein said first and second piezoelectric bodies have substantially the same spatial piezoelectric orientation, an intermediate intermediate electrode being arranged between said first and said second piezoelectric body forming a first terminal of said acoustic resonator, and first and second electrodes, wherein said first electrode is arranged such that said first piezoelectric body is arranged between said first electrode and said intermediate electrode, wherein said second electrode is arranged such that said second piezoelectric body is arranged between said second electrode and said intermediate electrode, and wherein said first and said second electrode are electrically connected to each other forming a second terminal of said acoustic resonator.

Abstract: A bulk acoustic wave device includes first and second resonators, which are acoustically coupled and electrically connected in parallel.

Abstract: A method for manufacturing a filter device is provided. The filter device comprises a coupled resonator at a first site, a shunt resonator at a second site and a series resonator at a third site, the coupled resonator comprising a first and a second resonator. The method comprising a step of providing a substrate with a piezoelectric layer sandwiched between a first electrode and a first part of a second electrode at the first site and the second site, the piezoelectric layer sandwiched between the first electrode and a second part of the second electrode at the third site. The method further comprising the step of forming a coupling layer on the second electrode, the step of forming a further piezoelectric layer sandwiched between a further first electrode and a further second electrode at the third site and the step of removing the coupling layer at the second and third sites.