Abstract: A multiplexer device includes a single die, at least three acoustic filters and at least one antenna port arranged on the single die, and a shunt inductance connected between each of the at least one antenna port and ground. Each acoustic filter includes one of a transmit or receive filter corresponding to a predetermined radio frequency band. The at least one antenna port is connected to at least one antenna, respectively, where each of the at least one antenna port is further connected to at least one acoustic filter arranged on the single die, and is configured to pass RF signals corresponding to the predetermined RF band of the connected at least one acoustic filter. The shunt inductance provides impedance matching between each of the at least one antenna port and each of the at least one acoustic filter connect to the at least one antenna port.

Abstract: An acoustic resonator device includes an annular acoustic resonator, a heater coil and a heat sensor. The annular acoustic resonator is positioned over a trench formed in a substrate of the acoustic resonator device. The heater coil is disposed around a perimeter of the annular acoustic resonator, the heater coil including a resistor configured to receive a heater current. The heat sensor is configured to adjust the heater current in response to a temperature of the heater coil.

Abstract: An apparatus includes a silicon (Si) substrate having a first surface and a second surface, the silicon substrate having a resistivity at room temperature greater than approximately 1000 ?-cm, and less than approximately 15000 ?-cm; and a piezoelectric layer disposed over the substrate and having a first surface and a second surface. The piezoelectric layer may have a thickness in the range of approximately 0.5 ?m to approximately 30.0 ?m, and is substantially without iron (Fe).

Abstract: An acoustic resonator structure comprises: a substrate having a cavity, which has a plurality of sides; a first electrode disposed over the cavity; a piezoelectric layer disposed over a portion of the first electrode and extending over at least one of the sides; and a second electrode disposed over the piezoelectric layer, an overlap of the first electrode, the piezoelectric layer and the second electrode forming an active area of the FBAR. The active area of the FBAR is completely suspended over the cavity.

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: An acoustic resonator device includes an annular acoustic resonator, a heater coil and a heat sensor. The annular acoustic resonator is positioned over a trench formed in a substrate of the acoustic resonator device. The heater coil is disposed around a perimeter of the annular acoustic resonator, the heater coil including a resistor configured to receive a heater current. The heat sensor is configured to adjust the heater current in response to a temperature of the heater coil. A feedback circuit is used to control a temperature of the acoustic resonator device.

Abstract: A bulk acoustic wave (BAW) resonator device comprises a heating coil disposed over a first side of the piezoelectric layer and substantially around a perimeter adjacent to the active area of the acoustic resonator, the heating coil comprising a resistor configured to receive a heater current; and a heat sensor disposed over a second side of the piezoelectric layer and opposing the first side, the heat sensor configured to adjust the heater current in response to a temperature of the heating coil.

Abstract: An acoustic resonator device comprises: a substrate comprising a cavity or an acoustic mirror; a first electrode disposed over the substrate; a piezoelectric layer disposed over the first electrode; and a second electrode disposed over the piezoelectric layer. The first electrode or the second electrode, or both, are made of an electrically conductive material having a positive temperature coefficient.

Abstract: An acoustic resonator structure comprises: a substrate having a cavity, which has a plurality of sides; a first electrode disposed over the cavity; a piezoelectric layer disposed over a portion of the first electrode and extending over at least one of the sides; and a second electrode disposed over the piezoelectric layer, an overlap of the first electrode, the piezoelectric layer and the second electrode forming an active area of the FBAR. The active area of the FBAR is completely suspended over the cavity.

Abstract: A surface acoustic wave (SAW) resonator includes a piezoelectric layer disposed over a substrate, and a plurality of electrodes disposed over the first surface of the piezoelectric layer.

Abstract: A surface acoustic wave (SAW) resonator includes a piezoelectric layer disposed over a substrate, and a plurality of electrodes disposed over the first surface of the piezoelectric layer. A layer is disposed between the substrate and the piezoelectric layer. A surface of the layer has a smoothness sufficient to foster atomic bonding between layer and the piezoelectric layer. A plurality of features provided on a surface of the piezoelectric layer reflects acoustic waves and reduces the incidence of spurious modes in the piezoelectric layer.

Abstract: A surface acoustic wave (SAW) resonator includes a piezoelectric layer disposed over a substrate, and a plurality of electrodes disposed over the first surface of the piezoelectric layer.

Abstract: A surface acoustic wave (SAW) resonator includes a piezoelectric layer disposed over a substrate, and a plurality of electrodes disposed over the first surface of the piezoelectric layer. A layer is disposed between the substrate and the piezoelectric layer. A surface of the layer has a smoothness sufficient to foster atomic bonding between layer and the piezoelectric layer. A plurality of features provided on a surface of the substrate reflects acoustic waves and reduce the incidence of spurious modes in the piezoelectric layer.

Abstract: A surface acoustic wave (SAW) resonator includes a piezoelectric layer disposed over a substrate, and a plurality of electrodes disposed over the first surface of the piezoelectric layer. A layer is disposed between the substrate and the piezoelectric layer. A surface of the layer has a smoothness sufficient to foster atomic bonding between layer and the piezoelectric layer. A plurality of features provided on a surface of the piezoelectric layer reflects acoustic waves and reduces the incidence of spurious modes in the piezoelectric layer.

Abstract: A surface acoustic wave (SAW) resonator includes a piezoelectric layer disposed over a substrate, and a plurality of electrodes disposed over the first surface of the piezoelectric layer. A layer is disposed between the substrate and the piezoelectric layer. A silicon layer disposed between a first surface of the layer and a second surface of the piezoelectric layer. A first surface of the silicon layer has a smoothness sufficient to foster atomic bonding between the first surface of the silicon layer and the second surface of the piezoelectric layer.

Abstract: A surface acoustic wave (SAW) resonator includes a piezoelectric layer disposed over a substrate, and a plurality of electrodes disposed over the first surface of the piezoelectric layer. A layer is disposed between the substrate and the piezoelectric layer. A surface of the layer has a smoothness sufficient to foster atomic bonding between layer and the piezoelectric layer. A plurality of features provided on a surface of the substrate reflects acoustic waves and reduce the incidence of spurious modes in the piezoelectric layer.

Abstract: A surface acoustic wave (SAW) resonator includes a piezoelectric layer disposed over a substrate, and a plurality of electrodes disposed over the first surface of the piezoelectric layer. A layer is disposed between the substrate and the piezoelectric layer. A surface of the layer has a smoothness sufficient to foster atomic bonding between layer and the piezoelectric layer. A plurality of features provided on a surface of the substrate reflects acoustic waves and reduce the incidence of spurious modes in the piezoelectric layer.

Abstract: An acoustic resonator device includes a composite first electrode on a substrate, a piezoelectric layer on the composite electrode, and a second electrode on the piezoelectric layer. The first electrode includes a buried temperature compensating layer having a positive temperature coefficient. The piezoelectric layer has a negative temperature coefficient, and thus the positive temperature coefficient of the temperature compensating layer offsets at least a portion of the negative temperature coefficient of the piezoelectric layer.

Abstract: An acoustic resonator comprises: an acoustic resonator device comprises: a composite first electrode disposed over a substrate, the composite first electrode comprising: a first electrically conductive layer provided over the substrate; a first interlayer disposed on the first electrical conductive layer; a buried temperature compensation layer disposed over the first interlayer; a second interlayer disposed over the temperature compensation layer; a second electrically conductive layer disposed over the second interlayer, a piezoelectric layer disposed over the composite first electrode; and a second electrode disposed over the piezoelectric layer.

Abstract: An film bulk acoustic wave resonator (FBAR) structure has an FBAR and a via disposed substantially directly beneath the FBAR. The via is in thermal contact with the FBAR. A plurality of vias may be included. The via(s) serve to dissipate heat generated by the FBAR structure during operation.