Acoustic resonators, such as bulk acoustic wave (BAW) resonators, are disclosed that include phase shift structures. Acoustic resonators, including stacked crystal filters (SCFs) and coupled resonator filters (CRFs), may include inverted piezoelectric layers that are configured to provide built-in phase shift capabilities. Circuit topologies that include such SCFs may be provided with simplified structures and reduced loss. Circuit topologies with such CRFs may be provided with more symmetrical electrical connections and improved phase balance over operating frequencies. SCFs with phase shift structures may additionally include spurious mode suppression by modifying piezoelectric coupling profiles within one or more layers. Mode suppression configurations may include structures with one or more inverted polarity piezoelectric layers, one or more non-piezoelectric layers, one or more thicker electrodes of the SCF, and combinations thereof.

A packaged acoustic wave filter component can include an acoustic wave device including a first piezoelectric layer and an interdigital transducer electrode on the first piezoelectric layer. A support layer may be included over the acoustic wave device, and the packaged hybrid filter component can also include a bulk acoustic wave resonator over the support layer. A cap layer may extend over and encapsulate the bulk acoustic wave resonator. One or more external vias may extend through the support layer and the underlying layers of the acoustic wave device to provide electrical communication with the packaged bulk acoustic wave generator.

An acoustic wave filter component can include a surface acoustic wave device including a first piezoelectric layer, an interdigital transducer electrode on the first piezoelectric layer, and an additional layer, such as a temperature compensation layer, over the interdigital transducer electrode. The acoustic wave filter component can also include a bulk acoustic wave resonator supported by the additional layer. The additional layer may be a layer on which a surface acoustic wave of the surface acoustic wave device will propagate. The bulk acoustic wave resonator may include an air cavity, where a shape of the air cavity is defined in part by the additional layer.

An acoustic wave filter component can include an acoustic wave device including a multi-layer piezoelectric substrate. The multi-layer piezoelectric substrate can include at least a support substrate and a piezoelectric layer. The acoustic wave device can include an interdigital transducer electrode on the piezoelectric layer. An additional layer can be located over the interdigital transducer electrode. The acoustic wave filter component can also include a bulk acoustic wave resonator supported by the additional layer. The acoustic wave device can be a boundary wave resonator, and one or more boundary wave resonators may be provided in a stacked arrangement, with the bulk acoustic wave resonator in the top layer of the stacked arrangement. The acoustic wave device can also be a temperature-compensated surface acoustic wave device.

Acoustic resonators, such as bulk acoustic wave (BAW) resonators, are disclosed that include phase shift structures. Acoustic resonators, including stacked crystal filters (SCFs) and coupled resonator filters (CRFs), may include inverted piezoelectric layers that are configured to provide built-in phase shift capabilities. Circuit topologies that include such SCFs may be provided with simplified structures and reduced loss. Circuit topologies with such CRFs may be provided with more symmetrical electrical connections and improved phase balance over operating frequencies. SCFs with phase shift structures may additionally include spurious mode suppression by modifying piezoelectric coupling profiles within one or more layers. Mode suppression configurations may include structures with one or more inverted polarity piezoelectric layers, one or more non-piezoelectric layers, one or more thicker electrodes of the SCF, and combinations thereof.

An acoustic wave device system with its piezoelectric layer originating from a single crystal piezoelectric wafer/substrate is invented along with sets of detailed process steps to fabricate such a device using wafer-to-wafer and/or die-to-wafer bonding technologies. The proposed device system is particularly good to make bulk acoustic wave (BAW) devices. Methods allowing the single crystal piezoelectric wafer/substrate to be re-used are also given. The proposed methods include detailed process steps to allow heterogeneous integration of electrical chips into the system in a very cost efficient manner. The invention provides a practical and low-cost approach to fabricate the radio frequency (RF) front end chip incorporating RF filters and electronic components integrated into a small footprint which is particularly useful for mobile device and RF stations.

An electronic component includes: a substrate; a device chip, in which a functional element is located on a lower surface thereof, that is mounted on an upper surface of the substrate so that the functional element and the upper surface of the substrate are opposite to each other via an air gap; a ring-shaped metal layer that is located on the upper surface of the substrate, surrounds the device chip in a plan view, and has a protruding part located along an outer periphery thereof, an outer side surface of the ring-shaped metal layer being higher than an inner side surface thereof; a metal sealer that surrounds the device chip in the plan view, and is bonded on an upper surface of the ring-shaped metal layer; and a metal film that is located on side surfaces of the metal sealer and the ring-shaped metal layer.

A method for the batch production of acoustic wave filters comprises: synthesizing N theoretical filters, each filter defined by a set of j theoretical resonator(s) having a triplet C.sub.0ij,eq, .sub.rij,eq and .sub.aij,eq, these parameters grouped into subsets; determining a reference resonator structure for each subset, naturally having a resonant frequency .sub.r,ref, where .sub.aij,eq<.sub.r,ref<.sub.rij,eq; determining, for each theoretical resonator, an elementary building block comprising an intermediate resonator R.sub.ij, a parallel reactance Xp.sub.ij and/or a series reactance Xs.sub.ij, the intermediate resonator R.sub.ij having a triplet C.sub.0ij, .sub.r,ref and .sub.a,ref, the parameters C.sub.0ij, Xpij and/or Xs.sub.ij defined so the elementary building block has a triplet: C.sub.0ij,eq, .sub.rij,eq and .sub.aij,eq; determining the geometrical dimensions of the actual resonators R.sub.ij of the filters so they have a capacitance C.sub.0ij; producing each actual resonator; associating series and/or parallel reactances with actual resonators in order to form the elementary building blocks.

A surface acoustic wave device assembly includes a collective board, first circuit portions provided on the collective board and respectively including first hot terminals and first ground terminals, a second circuit portion provided on the collective board and including second hot terminals and second ground terminals, and a power supply wiring provided on the collective board so as to surround the periphery of the first circuit portions and the second circuit portion. The first circuit portions include surface acoustic wave devices defining band pass filters. The second circuit portion defines a band pass filter. The first ground terminals and first hot terminals, and the second ground terminal are connected to the power supply wiring, the second hot terminals are not connected to the power supply wiring, and pass bands of the surface acoustic wave devices and a pass band of the band pass filter defined by the second circuit portion are the same or substantially the same.

An acoustic wave filter component can include a surface acoustic wave device including a first piezoelectric layer, an interdigital transducer electrode on the first piezoelectric layer, and an additional layer, such as a temperature compensation layer, over the interdigital transducer electrode. The acoustic wave filter component can also include a bulk acoustic wave resonator supported by the additional layer. The additional layer may be a layer on which a surface acoustic wave of the surface acoustic wave device will propagate. The bulk acoustic wave resonator may include an air cavity, where a shape of the air cavity is defined in part by the additional layer.