RF360 EUROPE GMBH

A package that includes a substrate, an integrated device coupled to the substrate, an encapsulation layer located over the substrate, at least one encapsulation layer interconnect located in the encapsulation layer, and a metal layer located over the encapsulation layer. The substrate includes at least one dielectric layer and a plurality of interconnects. The encapsulation layer interconnect is coupled to the substrate. The metal layer is configured as an electromagnetic interference (EMI) shield for the package. The metal layer is located over a backside of the integrated device.

Aspects of the disclosure relate to devices, wireless communication apparatuses, methods, and circuitry implementing filters with electroacoustic vertical coupling. One aspect is a filter comprising a piezoelectric substrate having a first piezoelectric surface and a second piezoelectric surface opposite the first piezoelectric surface. The filter further comprises a first electroacoustic resonator comprising a first interdigital transducer (IDT) disposed on or over the first piezoelectric surface of the piezoelectric substrate and a second electroacoustic resonator comprising a second IDT disposed on or over the second piezoelectric surface of the piezoelectric substrate. The second electroacoustic resonator is electrically coupled to the first electroacoustic resonator in series or in parallel.

An apparatus for filtering is disclosed that implements a double-mode surface-acoustic-wave filter having a transition region with a partly uniform geometric property. In an example aspect, the double-mode surface-acoustic-wave filter includes at least one interdigital transducer with multiple fingers. The multiple fingers include a first set of fingers having a geometric property and a second set of fingers. The second set of fingers is positioned adjacent to the first set of fingers and is associated with an outer edge of the at least one interdigital transducer. The geometric property across a subset of the second set of fingers is substantially uniform. A value of the geometric property across the subset of the second set of fingers is different than a value of the geometric property across the first set of fingers.

Disclosed are apparatuses and methods for fabricating the apparatuses. In one aspect, an apparatus includes a high-power die mounted on a backside of a package substrate. A heat transfer layer is disposed on the backside of the high-power die. A plurality of heat sink interconnects is coupled to the heat transfer layer. The plurality of heat sink interconnects is located adjacent the high-power die in a horizontal direction.

A bulk acoustic wave (BAW) device comprises a layer stack including first and second electrodes, a first piezoelectric layer between the electrodes, and a second piezoelectric layer between the first piezoelectric layer and the second electrode. A polarization of a crystal structure of the second piezoelectric layer is opposite to a polarization of a crystal structure of the first piezoelectric layer to achieve higher order resonant frequencies in the BAW device by means other than merely thinning layers in the layer stack. In some examples, the BAW device is a two-terminal device and does not include a metal layer configured to be a third electrode. In some examples, the BAW device includes at least one intermediate layer between the first and second piezoelectric layers, and a total combined thickness of the at least one intermediate layer is less than 4% of a total thickness of the layer stack.

Aspects of the disclosure relate to wireless communication, and high-frequency filters with resonators. One aspect is a device including first and second busbars, and electrode fingers coupled between the busbars, with electrode fingers extending different distances toward an opposite busbar such that a second end of each of the electrode fingers collectively form wave shapes. The device further includes pluralities of gap reflectors positioned between the wave shapes and a nearest busbar.

A bulk acoustic wave (BAW) device comprises a piezoelectric layer disposed between a first electrode layer and a sandwich electrode. The sandwich electrode includes a first layer of a first material having a first acoustic impedance and a second layer of a second material having a second acoustic impedance that is less than the first acoustic impedance of the first layer. The second layer of the sandwich electrode having the lower acoustic impedance is disposed between the first layer and the piezoelectric layer. The sandwich electrode combined with the piezoelectric layer and first electrode can cause the BAW device to resonate at a frequency whose wavelength corresponds to an acoustic cavity length of the BAW device, depending on an acoustic mirror included on one side of the BAW device. In one example, the acoustic cavity length is about 1.5 times of the resonant frequency wavelength.

An apparatus is disclosed for implementing a microacoustic filter with a cavity stack. In an example aspect, the apparatus includes a microacoustic filter with an electrode structure, a cavity stack, a buffer layer, and a piezoelectric layer. The cavity stack comprises a conductive layer, a substrate layer, and at least two pillars extending past a plane defined by a surface of the substrate layer and towards the conductive layer to form a cavity between the substrate layer and the conductive layer. The buffer layer is disposed between the conductive layer of the cavity stack and the electrode structure. The piezoelectric layer is disposed between the buffer layer and the electrode structure.

Aspects of the disclosure relate to devices, wireless communication apparatuses, methods, and circuitry implementing bulk wave suppression in a stacked electroacoustic device. One aspect includes a first substrate comprising a first surface and a second surface, where the second surface is opposite the first surface, a first AW resonator circuit positioned on the first surface of the first substrate, a plurality of elements including a first element, where the plurality of elements are positioned on the second surface of the first substrate, and where the first element is aligned with the first AW resonator circuit, and a second substrate comprising a first surface and a second surface, where the plurality of elements are positioned on the first surface of the second substrate, and where the plurality of elements create a cavity between the first substrate and the second substrate.

A bulk acoustic wave (BAW) device with resonance-tuned layer stack is disclosed. The BAW device includes two acoustic resonators with top electrodes in different regions on a top side of a piezoelectric layer. The BAW device includes an acoustic mirror on a bottom side of the piezoelectric layer and a bottom electrode between the acoustic mirror and the piezoelectric layer. The piezoelectric layer includes a recess in a second region on the bottom side of the piezoelectric layer. The bottom electrode is disposed in the recess on the bottom side of the piezoelectric layer. A distance between a first top electrode in a first region and the bottom electrode may be greater than a distance between a second top electrode in the second region and the bottom electrode.