Abstract: A method for manufacturing a composite includes providing a first template including a cutout for a first layer of the composite, disposing the first layer in the cutout, and disposing a tablet, provided with an adhesive, on the first layer such that the first layer adheres to the tablet. Next, the tablet is removed, together with the first layer adhered thereto, from the cutout, and an adhesive is applied to a side of the first layer facing away from the tablet. A second template is provided that includes a cutout for a second layer of the composite, and then the second layer is disposed in the cutout. The tablet, together with the first layer adhered thereto, is disposed on the second layer disposed in the cutout of the second template, and the tablet is removed, together with the composite produced from the first and second layers, from the second template.

Abstract: A method for manufacturing a composite includes providing a first template including a cutout for a first layer of the composite, disposing the first layer in the cutout, and disposing a tablet, provided with an adhesive, on the first layer such that the first layer adheres to the tablet. Next, the tablet is removed, together with the first layer adhered thereto, from the cutout, and an adhesive is applied to a side of the first layer facing away from the tablet. A second template is provided that includes a cutout for a second layer of the composite, and then the second layer is disposed in the cutout. The tablet, together with the first layer adhered thereto, is disposed on the second layer disposed in the cutout of the second template, and the tablet is removed, together with the composite produced from the first and second layers, from the second template.

Abstract: A bulk acoustic wave (BAW) resonator includes: an acoustic reflector disposed in a substrate; a lower electrode disposed over the acoustic reflector; a piezoelectric layer disposed over the lower electrode; and an upper electrode disposed over the piezoelectric layer. A contacting overlap of the lower electrode, the piezoelectric layer and the upper electrode over the acoustic reflector comprising an active area of the BAW resonator. An opening exists in the upper electrode in a region of the BAW resonator susceptible to unacceptable overheating.

Abstract: A bulk acoustic wave (BAW) resonator includes: an acoustic reflector disposed in a substrate; a lower electrode disposed over the acoustic reflector; a piezoelectric layer disposed over the lower electrode; and an upper electrode disposed over the piezoelectric layer. A contacting overlap of the lower electrode, the piezoelectric layer and the upper electrode over the acoustic reflector comprising an active area of the BAW resonator. An opening exists in the upper electrode in a region of the BAW resonator susceptible to unacceptable overheating.

Abstract: A bulk acoustic wave (BAW) resonator comprises: a first electrode; a second electrode comprising a plurality of sides, wherein at least one of the sides is a connection side; a piezoelectric layer disposed between the first and second electrodes, and an acoustic reflective element disposed beneath the first electrode, the second electrode and the piezoelectric layer, wherein an overlap of the reflective element, the first electrode, the second electrode, and the piezoelectric layer defines an active area of the acoustic resonator; a bridge adjacent to a termination of the active area of the BAW resonator; and a discontinuity disposed in the bridge.

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 is disposed adjacent to one of the sides of the second electrode.

Abstract: A bulk acoustic wave (BAW) resonator includes: an acoustic reflector disposed in a substrate; a lower electrode disposed over the acoustic reflector; a piezoelectric layer disposed over the lower electrode; and an upper electrode disposed over the piezoelectric layer. A contacting overlap of the lower electrode, the piezoelectric layer and the upper electrode over the acoustic reflector comprising an active area of the BAW resonator. An opening exists in the upper electrode in a region of the BAW resonator susceptible to unacceptable overheating.

Abstract: A bulk acoustic wave (BAW) resonator comprises: a first electrode; a second electrode comprising a plurality of sides, wherein at least one of the sides is a connection side; a piezoelectric layer disposed between the first and second electrodes, and an acoustic reflective element disposed beneath the first electrode, the second electrode and the piezoelectric layer, wherein an overlap of the reflective element, the first electrode, the second electrode, and the piezoelectric layer defines an active area of the acoustic resonator; a bridge adjacent to a termination of the active area of the BAW resonator; and a discontinuity disposed in the bridge.

Abstract: A method is provided for fabricating a bulk acoustic wave (BAW) resonator device. The method includes forming an etch stop layer over a bottom electrode and a substrate; forming a dielectric layer on the etch stop layer; forming a photomask over the dielectric layer defining an opening over the bottom electrode; etching a portion the dielectric layer through the opening of the photomask to the etch stop layer to create a corresponding opening in the dielectric layer; removing the photomask, leaving un-etched protruding portions of the dielectric layer around the opening in the dielectric layer; and removing the protruding portions of the dielectric layer, a portion of the etch stop layer located over the bottom electrode, and a minimal portion of the bottom electrode to provide a planarized surface including a top surface of the bottom electrode and an adjacent top surface of the dielectric layer deposited over the substrate.

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 is disposed adjacent to one of the sides of the second electrode.

Abstract: A method is provided for fabricating a bulk acoustic wave (BAW) resonator device. The method includes forming an etch stop layer over a bottom electrode and a substrate; forming a dielectric layer on the etch stop layer; forming a photomask over the dielectric layer defining an opening over the bottom electrode; etching a portion the dielectric layer through the opening of the photomask to the etch stop layer to create a corresponding opening in the dielectric layer; removing the photomask, leaving un-etched protruding portions of the dielectric layer around the opening in the dielectric layer; and removing the protruding portions of the dielectric layer, a portion of the etch stop layer located over the bottom electrode, and a minimal portion of the bottom electrode to provide a planarized surface including a top surface of the bottom electrode and an adjacent top surface of the dielectric layer deposited over the substrate.

Abstract: In accordance with a representative embodiment, a BAW resonator structure comprises: a first BAW resonator comprising a first lower electrode, a first upper electrode and a first piezoelectric layer disposed between the first lower electrode and the first upper electrode; and a second BAW resonator comprising a second lower electrode, a second upper electrode and a second piezoelectric layer disposed between the second lower electrode and the second upper electrode. The BAW resonator structure also comprises a single-material acoustic coupling layer disposed between the first and second BAW resonators. The single-material acoustic coupling layer comprises an inhomogeneous acoustic property across a thickness of the single-material acoustic coupling layer.

Abstract: A bulk acoustic wave (BAW) filter device includes a first port, a second port, a first coupled resonator filter stage, a second coupled resonator filter stage and a filter section. The first coupled resonator filter stage includes a first BAW resonator connected to the first port and a second BAW resonator acoustically coupled to the first BAW resonator. The second coupled resonator filter stage includes a third BAW resonator connected to the second port and a fourth BAW resonator acoustically coupled to the third BAW resonator. The filter section includes a fifth BAW resonator, the fifth BAW resonator connected between the second BAW resonator and the fourth BAW resonator.

Abstract: A mirror for a piezoelectric resonator consisting of alternately arranged layers of high and low acoustic impedance is manufactured by at first producing a first layer on which a second layer is produced, so that the second layer partially covers the first layer. Then, a planarization layer is applied on the first layer and on the second layer. Subsequently, a portion of the second layer is exposed by structuring the planarization layer, wherein the portion is associated with an active region of the piezoelectric resonator. Finally, the resulting structure is planarized by removing the portions of the planarization layer remaining outside the portion.

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

Abstract: In accordance with a representative embodiment, a BAW resonator structure comprises: a first BAW resonator comprising a first lower electrode, a first upper electrode and a first piezoelectric layer disposed between the first lower electrode and the first upper electrode; and a second BAW resonator comprising a second lower electrode, a second upper electrode and a second piezoelectric layer disposed between the second lower electrode and the second upper electrode. The BAW resonator structure also comprises a single-material acoustic coupling layer disposed between the first and second BAW resonators. The single-material acoustic coupling layer comprises an inhomogeneous acoustic property across a thickness of the single-material acoustic coupling layer.

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: 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 mirror for a piezoelectric resonator consisting of alternately arranged layers of high and low acoustic impedance is manufactured by at first producing a first layer on which a second layer is produced, so that the second layer partially covers the first layer. Then, a planarization layer is applied on the first layer and on the second layer. Subsequently, a portion of the second layer is exposed by structuring the planarization layer, wherein the portion is associated with an active region of the piezoelectric resonator. Finally, the resulting structure is planarized by removing the portions of the planarization layer remaining outside the portion.