PACKAGED ACOUSTIC WAVE DEVICES WITH MULTILAYER PIEZOELECTRIC SUBSTRATE

Disclosed is a packaged acoustic wave component and a method for making a packaged acoustic wave component. The packaged acoustic wave component comprises a substrate, a dielectric layer disposed over the substrate, a piezoelectric structure disposed over the dielectric layer, an electrode structure disposed over the piezoelectric structure, a polymer structure including a polymer structure wall portion and a polymer structure roof portion configured to form a cavity over the electrode structure, a metal structure disposed over the polymer structure, and a buffer coating disposed over the metal structure. The polymer structure includes a polymer structure lateral portion sandwiched between the substrate, the dielectric layer, or the piezoelectric structure on one side, and both the metal structure and the buffer coating on the other side.

BACKGROUND

Technical Field

Embodiments of this disclosure relate to acoustic wave devices, in particular to packaged acoustic wave components, which may also be designated as acoustic wave component packages.

Description of Related Technology

Acoustic wave filters can be implemented in radio frequency electronic systems. For instance, filters in a radio frequency front end of a mobile phone can include acoustic wave filters. An acoustic wave filter can filter a radio frequency signal. An acoustic wave filter can be a band pass filter. A plurality of acoustic wave filters can be arranged as a multiplexer. For example, two acoustic wave filters can be arranged as a duplexer.

An acoustic wave filter can include a plurality of resonators arranged to filter a radio frequency signal. Example acoustic wave filters include surface acoustic wave (SAW) filters and bulk acoustic wave (BAW) filters. A surface acoustic wave resonator can include an interdigital transductor electrode on a piezoelectric substrate. The surface acoustic wave resonator can generate a surface acoustic wave on a surface of the piezoelectric layer on which the interdigital transductor electrode is disposed.

The packaging process for multilayer piezoelectric substrate packages with an acoustic wave device, so as to produce a packaged acoustic wave component, can apply stresses to the piezoelectric layer (e.g., during heat cycle testing) that can result in reliability issues including cracking of the piezoelectric layer.

SUMMARY

Accordingly, there is a need for a packaged acoustic wave component, in particular a surface acoustic wave (e.g., SAW or temperature compensated surface acoustic wave (TCSAW)) package with improved reliability that can withstand stresses (e.g., from heat cycle testing) during the packaging process.

In accordance with one aspect of this disclosure, a packaged acoustic wave component comprises a substrate, a dielectric layer disposed over the substrate, a piezoelectric structure disposed over the dielectric layer, an electrode structure disposed over the piezoelectric structure, a polymer structure including a polymer structure wall portion and a polymer structure roof portion configured to form a cavity over the electrode structure, a metal structure disposed over the polymer structure, and a buffer coating disposed over the metal structure, the polymer structure having a polymer structure lateral portion sandwiched between the substrate, the dielectric layer, or the piezoelectric structure on one side, and both directly the metal structure and directly the buffer coating on the other side.

In accordance with another aspect of this disclosure, a method of making a packaged acoustic wave component comprises forming an acoustic wave device including forming or providing a substrate, forming or providing a piezoelectric structure over at least a portion of the substrate, forming or providing an electrode structure disposed over the piezoelectric structure, providing a polymer structure lateral portion over the substrate or over the piezoelectric layer, forming or providing a polymer structure including a polymer structure wall portion and a polymer structure roof portion configured to form a cavity over the electrode structure, forming or providing a metal structure disposed over the polymer structure, and forming a buffer coating disposed over the metal structure, the polymer structure having a polymer structure lateral portion sandwiched between the substrate, the dielectric layer, or the piezoelectric structure on one side, and both directly the metal structure as well as directly the buffer coating on the other side.

DETAILED DESCRIPTION

Acoustic wave filters can filter radio frequency (RF) signals in a variety of implementations, such as in an RF front end of a mobile phone. An acoustic wave filter can be implemented with surface acoustic wave (SAW) devices. SAW devices include SAW resonators, SAW delay lines, and multi-mode SAW (MMS) filters (e.g., double mode SAW (DMS) filters). Any features of the SAW resonators and/or devices discussed herein can be implemented in any suitable SAW device.

In general, high quality factor (Q), large effective electromechanical coupling coefficient (k2), high frequency ability, and spurious free response can be significant aspects for acoustic wave elements to enable low-loss filters, delay lines, stable oscillators, and sensitive sensors.

Multi-layer piezoelectric substrate (MPS) SAW resonators can thermally insulate an interdigital transducer electrode and a piezoelectric layer. By reducing dissipative thermal impedance of the SAW device the ruggedness and power handling can be improved.

Some MPS SAW resonators have achieved a high Q by confining energy and good thermal dissipation using a silicon (Si) support layer. However, such approaches have encountered technical challenges related to undesirable higher frequency spurious responses.

Some other MPS SAW resonators have achieved a high Q by confining energy and have also reduced higher frequency spurious responses. However, such approaches have exhibited relatively low thermal heat dissipation.

Aspects of the present disclosure relate to SAW resonators that include a support substrate or layer (e.g., a single crystal supporting substrate), a functional layer (e.g., a dielectric layer) over the support substrate or layer, a piezoelectric layer (e.g., a lithium niobate (LN or LiNbO3) layer or a lithium tantalate (LT or LiTaO3) layer) over the functional layer, and an interdigital transducer (IDT) electrode over the piezoelectric layer. Such SAW resonators can also include a temperature compensation layer (e.g., a silicon dioxide (SiO2) layer) over the IDT electrode in certain embodiments. The SAW resonators can also include an adhesion layer disposed between the support substrate and the functional layer and/or an adhesion layer between the functional layer and the piezoelectric layer in certain embodiments.

SAW resonators with the functional layer and the support layer or substrate can beneficially provide a relatively high effective electromechanical coupling coefficient (k2), a relatively high quality factor (Q), a relatively high power durability and thermal dissipation, and reduced high frequency spurious responses. The high electromechanical coupling coefficient (k2) can be beneficial for relatively wide bandwidth filters. The high quality factor (Q) can beneficially lead to a relatively low insertion loss. The reduced high frequency spurious response may make the SAW resonators compatible with multiplexing with higher frequency bands.

In an embodiment, an MPS SAW resonator includes a piezoelectric layer over a functional layer over a silicon support substrate or layer. The silicon support substrate can reduce thermal impedance of the MPS SAW resonator. The functional layer can be a single crystal layer arranged to confine acoustic energy and reduce a higher frequency spurious response. The piezoelectric layer, the functional layer, and the silicon support substrate can all be single crystal layers.

Embodiments of MPS SAW resonators (e.g., packages) will now be discussed. Any suitable principles and advantages of these MPS SAW resonators can be implemented together with each other in an MPS SAW resonator and/or in an acoustic wave filter. MPS SAW resonators (e.g., packages) disclosed herein can have lower loss than certain bulk acoustic wave devices.

FIG.1illustrates a packaged acoustic wave component100(e.g., a multi-layer piezoelectric substrate (MPS) package or structure) according to the prior art. The component100has a substrate116, an additional (e.g., functional, dielectric) structure or layer114disposed over (e.g., bonded to) the substrate116, and a piezoelectric structure or layer112disposed over (e.g., bonded to) the functional layer114. The functional layer114may, for example, comprise silicon ducts to improve thermal properties and/or the temperature coefficient of frequency (TCF) of the component100. An electrode structure, specifically an interdigital transducer (IDT) electrode110, is disposed on (e.g., connected to) the piezoelectric layer112as part of a first metal layer. The dielectric layer114can also be designated as a functional layer as it may provide one or more functions. On the first metal layer, a second metal layer M2 can be provided which usually has a greater thickness than the first metal layer to reduce its electrical resistance. The second metal layer M2 may be used to form signal lines connecting the IDT electrode110to contact terminals of the packaged acoustic wave component100, e.g., to solder connections104. In some embodiments, the two solder connections may be electrically coupled by the second metal layer M2 and used to provide redundant signal or ground connections.

With continued reference toFIG.1, a thermally conductive structure or package102is connected to the substrate116via at least piezoelectric layer112and functional (specifically, dielectric) layer114. The thermally conductive structure or package102includes a metal structure108and a polymer structure109disposed over at least a portion of the metal structure108. The polymer structure109may comprise, or consist of, a polyimide material and/or a polybenzoxazole (PB0) material. In addition, a structure containing a filler such as silicon dioxide, SiO2, may be applied to the polymer structure109.

The metal structure108and the polymer structure109are shaped so that a cavity C (e.g., open or hollow cavity, air cavity) exists between at least a portion of the polymer structure109and at least a portion of the piezoelectric layer112. The cavity C houses (or encloses) the IDT110and may house (or enclose) the functional layer114and/or the piezoelectric layer112partially or completely. The polymer structure109may thus comprise a polymer structure wall portion109A (forming the walls of the cavity C) and a polymer structure roof portion109B (forming the roof of the cavity C). The metal structure108can be made of copper (Cu). A buffer coating (or dielectric overcoat)106) is disposed over at least a portion of the metal structure108. The buffer coating106may be made of any suitable polymer which may be chosen such as to provide a desired hardness. One or more solder connections104are disposed on the metal structure108so that the metal structure108is between the solder connections104and the piezoelectric layer112. The metal structure108connects to the piezoelectric layer112via—not depicted—signal line(s) (e.g., so at least a portion of the piezoelectric layer112and dielectric layer114are disposed between the signal line(s) and the substrate116).

During the packaging process the piezoelectric layer112and/or the dielectric layer114can be subjected to high stresses, for example, due to the different thermal expansion performances of the substrate116and the thermally conductive structure or package102(e.g., during a heat cycle test), which are transferred to the piezoelectric layer112by the metal structure108via the signal line(s). Such high stresses can result in damage (e.g., deformation and/or cracks) to the piezoelectric layer112and/or dielectric layer114. Aspects and embodiments disclosed herein mitigate this problem.

FIG.2shows a packaged acoustic wave component200(e.g., a multi-layer piezoelectric substrate (MPS) package or structure) according to an embodiment. The packaged acoustic wave component200is similar to the packaged acoustic wave component100ofFIG.1. Thus, reference numerals used to designate the various components of the packaged acoustic wave component200are identical to those used for identifying the corresponding components of the packaged acoustic wave component100inFIG.1. Therefore, the structure and description for the various features and components of the packaged acoustic wave component100inFIG.1are understood to also apply to the corresponding features of the packaged acoustic wave component200inFIGS.2-4, except as described below or as shown differently in the figures.

The substrate116of the packaged acoustic wave component200can include (e.g., be made of or consist of) crystalline silicon (Si). In another example, the substrate116can be made of poly-silicon. In another example, the substrate116can be made of amorphous silicon. In another example, the substrate116can be made of silicon nitride (SiN). In another example, the substrate116can be made of sapphire. In another example, the substrate116can be made of quartz. In another example, the substrate116can be made of aluminum nitride (AlN). In another example, the substrate116can be made of polycrystalline ceramic (e.g., Mg2O4). In another example, the substrate116can be made of diamond. In other examples, the substrate116can be made of other suitable high impedance materials. An acoustic impedance of the substrate116can be higher than an acoustic impedance of the piezoelectric structure or layer112of the packaged acoustic wave component200.

The functional (e.g., temperature compensation, dielectric) structure or layer114of the packaged acoustic wave component200can have a lower acoustic impedance than the substrate116. The functional structure or layer114can increase adhesion between the substrate116and the piezoelectric structure or layer112of the component200(e.g., multi-layer piezoelectric substrate (MPS) package or structure). Alternatively or additionally, the functional structure or layer114can increase the heat dissipation of the component200. The functional structure or layer114can be made of silicon dioxide (SiO2). In some implementations, the functional structure or layer is excluded from the component or package200(e.g., the piezoelectric layer112is disposed on, adjacent to, or in contact with the substrate116).

In one implementation, the piezoelectric layer112can be made of lithium niobate (LN or LiNbO3). In another implementation, the piezoelectric layer112can be made of lithium tantalate (LT or LiTaO3). Though not shown, one or more resonators (e.g., including an interdigital transducer (IDT) electrode110, for example, between two reflectors) can be disposed on (e.g., attached or mounted to) the piezoelectric layer112.

The inventors have noticed that the piezoelectric layer112is susceptible to being damaged in a packaging process, i.e., in a process of providing a (preferably thermally conductive) package202over the piezoelectric layer112including the IDT electrodes110. The inventors have also found a solution to this problem as illustrated in the embodiment shown inFIG.2. In the embodiment illustrated inFIG.2the polymer structure209comprises, apart from the polymer structure wall portion209A and the polymer structure roof portion209B (analog to the polymer structure wall portion109A and the polymer structure roof portion109B ofFIG.1), a polymer structure lateral portion209C sandwiched between the piezoelectric layer112on one side, and the metal structure108and the buffer coating106on the other side. The polymer structure lateral portion209C acts as a stress buffer between the package202and the piezoelectric layer112especially during the attaching, or forming, of the package202on the piezoelectric layer112. Thermal stress on the piezoelectric layer112during packaging can be substantially reduced in this way.

Specifically, the metal structure108comprises a metal structure wall portion108A (seeFIGS.6and7), and the buffer coating106comprises a buffer coating wall portion106A (seeFIGS.6and7as well). The metal structure wall portion108A laterally surrounds and encloses the polymer wall portion209A and the buffer coating wall portion106A in turn laterally surrounds and encloses the metal structure wall portion108A. The polymer structure lateral portion209C extends from the polymer wall portion209A towards the outer edge of the packaged acoustic wave component200, maintaining contact with the piezoelectric layer112on one side, and the metal structure wall portion108A and the buffer coating wall portion106A on the other side. Thermal and other stress caused or exerted by the packaging on the piezoelectric layer112is therefore advantageously buffered by the polymer structure lateral portion209C. In some variants, the polymer structure lateral portion209C is in contact not only with the functional layer112but with the piezoelectric layer114and/or the substrate116(see, e.g.,FIG.4). The polymer structure209may comprise, or consist of, a polyimide, for example poly-oxydiphenylene-pyromellitimide (“Kapton”).

FIG.3shows a packaged acoustic wave component300(e.g., a multi-layer piezoelectric substrate (MPS) package or structure) according to an embodiment. The packaged acoustic wave component300is identical to the packaged acoustic wave component200ofFIG.2apart from the difference that in the packaged acoustic wave component300the second metal layer M2 is formed such that it contacts the metal structure wall portion108A to transmit signals. As shown inFIG.3, because the second metal layer M2 is advantageously deposited as a layer, it may be arranged at different distances from the substrate116depending on how many, how thick, and which elements or layers are present at each location when the second metal layer M2 is deposited. The second metal layer M2 may thus take on a stepped appearance. To provide the buffering effect, the polymer structure lateral portion209C is also arranged between a portion of the second metal layer M2 and the piezoelectric layer112. Since it is sufficient when only a small part of the second metal layer M2 contacts the metal structure wall portion108A,FIG.2andFIG.3may be seen as two different cross-sections of the same embodiment of a packaged acoustic wave component200,300, whereinFIG.3shows a cross-section that includes the portion of the second metal layer M2 contacting the metal structure wall portion108A, and whereinFIG.2shows a cross-section that does not include said portion.

FIG.4shows a packaged acoustic wave component400(e.g., a multi-layer piezoelectric substrate (MPS) package or structure) according to an embodiment. The packaged acoustic wave component400is a variant of the packaged acoustic wave component200and differs from it in that a piezoelectric layer312is provided instead of the piezoelectric layer112, and that a functional layer314is provided instead of the functional layer114. In this embodiment, the piezoelectric layer312(and optionally also the functional layer314) are recessed with respect to the edge of the substrate116. Thus, a gap is present between the piezoelectric layer312and the functional layer314on one side, and the polymer structure209on the other side. In this gap, the substrate116may be directly exposed to the cavity C. The gap may be a gap zone surrounding the piezoelectric layer312and the functional layer314completely in two dimensions on the surface of the substrate116. The polymer structure209in this embodiment therefore does not come into contact with either the piezoelectric layer312or the functional layer314. Instead, it is directly (in contact) sandwiched between the substrate116on one side, and the metal structure wall portion108A and the buffer coating wall portion106A on the other side. This further reduces the stress on the piezoelectric layer312, in particular, during packaging.

FIGS.5through7illustrate in their respective top portion schematic cross-sectional side views of packaged acoustic wave components according to several variants, and in their respective bottom portion graphs indicating a stress density (in GPa) as a function of distance (in micrometers) along the packaged acoustic wave component shown in the corresponding top portion. For the graphs, copper has been supposed as the material of the entire metal structure108and polyimide has been supposed as the material of the entire polymer structure209.

FIG.5shows the situation for the prior art packaged acoustic wave component100shown inFIG.1where the buffer coating106(specifically, its buffer coating wall portion106A) and the metal structure108(specifically, its metal structure wall portion108A) directly touch the functional layer112, for the sake of comparison.FIGS.6and7illustrate in their respective top sections variants for the outer lateral edges of the packaged acoustic wave components200-400.

FIG.5shows the prior art variant of packaged acoustic wave component100in which the polymer structure wall portion109A, the metal structure wall portion108A, and the buffer coating wall portion106A are arranged, in this order from inside to outside, on the piezoelectric layer112. The buffer coating wall portion106A as the outermost wall portion is recessed by a first distance R1from coextensive outer lateral edges of the substrate116, functional layer114, and piezoelectric layer112. As a result, as shown in the bottom section ofFIG.5, there is a stress spike right where the outer edge (or flank) of the buffer coating wall portion106A begins, i.e., at its onset.

By contrast,FIG.6shows the situation for the packaged acoustic wave component200ofFIG.2, wherein the polymer structure lateral portion209C is interposed between the metal structure wall portion108A and the buffer coating wall portion106A on one side and the piezoelectric layer112on the other side. In this variant, the polymer structure lateral portion209C is arranged flush with the outer lateral edges of the substrate116, functional layer114, and piezoelectric layer112, whereas the buffer coating wall portion106A is recessed from said outer lateral edges by the first distance R1. As is evident from the graph in the bottom section ofFIG.6, this reduces the initial stress spike, and furthermore significantly reduces the stress at the onset of the buffer coating wall portion106A.

FIG.7shows another variant that may be employed with any of the embodiments disclosed herein, e.g., any of the packaged acoustic wave components200,300, or400. In the embodiment ofFIG.7, a double-step recess layout is provided. The substrate116, the functional layer114, and the piezoelectric layer112are formed flush with each other, forming coextensive outer lateral edges as shown inFIG.5andFIG.6. Then, moving from outside to inside, recessed from said outer lateral edges by a second distance R2, the polymer structure lateral portion209C directly in contact with the piezoelectric layer112sets on. After another, third distance R3, the buffer coating wall portion106A in direct contact with the polymer structure lateral portion209C sets on. For the sake of comparison, R2+R3have been chosen to be equal to R1. The graph in the bottom section ofFIG.7clearly shows how the initial stress as well as the overall integral under the stress curve is further lowered by this design. Although described with respect to the piezoelectric layer112, the same design as inFIG.6or7may be applied when the polymer structure lateral portion209C directly contacts the functional layer114and/or the substrate116.

FIG.8illustrates a method500of making a packaged acoustic wave component (e.g., a multi-layer piezoelectric substrate (MPS) package or structure), such as the components200-400inFIGS.2through4. The method500includes the step502of forming or providing a substrate (e.g., substrate116). The method500includes the step504of forming or providing a functional (e.g., temperature compensation, dielectric) structure or layer (such as the functional layer114) over the substrate. The method500includes the step506of forming or providing a piezoelectric structure or layer (such as the piezoelectric layer112) over the functional layer. The method500may include an optional step508of removing (e.g., etching) an outer edge or boundary of the piezoelectric layer112and functional layer114, for example, for making the packaged acoustic wave component400ofFIG.4. The method500may include a step510of forming the polymer structure lateral portion209C on the piezoelectric layer112,312, a step512of forming the first metal layer including the IDT electrode110, and a step514of forming the second metal layer M2. In step514, in two or more locations the second metal layer M2 may be provided on top of the polymer structure lateral portion209C as shown inFIG.3such as to provide an electrical connection to the IDT electrodes110through the polymer structure wall portion209A. Apart from these two or more locations, the polymer structure lateral portion209C may be kept free from the second metal layer M2. In further steps, the remainder of the thermally conductive structure202in any of the described variants may be provided and attached to the intermediate product comprising the substrate116. The remainder of the thermally conductive structure202may be manufactured as a whole and then attached.

Alternatively, the following steps may be performed: In a step516, the polymer structure wall portion209A is provided (in particular, formed) over the polymer structure lateral portion209C and, if applicable, over parts of the second metal layer M2 that have been formed over the polymer structure lateral portion209C. In step518, the polymer structure roof portion209B is provided (in particular, formed) over the polymer structure wall portion209A to form the cavity C. In step520, the metal structure wall portion108A is provided (in particular, formed) such as to cover the polymer structure wall portion209A and to contact the second metal layer M2 in the two or more locations where the second metal layer M2 tunnels through the polymer structure wall portion209A. In this way, an electrically conductive connection is provided between the IDT electrodes110and the metal structure108. In a further step522, the remainder of the metal structure108, in particular, a roof structure of the metal structure108is provided and, in a further step524, the buffer coating106is provided, covering the polymer structure lateral portion209C and the metal structure108.

Since, as shown inFIG.2, the polymer structure209is the only part of the thermally conductive structure that contacts the portion of the packaged acoustic wave component200comprising the substrate116, it is also possible that the metal structure108and/or the buffer coating106are formed on the polymer structure209after the thermally conductive structure consisting of, or comprising, the polymer structure209has been attached in step510.

In one implementation, a method of making a radio frequency module includes the steps above for method500in addition to forming or providing a package substrate and attaching additional circuitry and the packaged acoustic wave component to the package substrate.

Advantageously, the packaged acoustic wave component200-400reduces the mechanical stress to which the piezoelectric and/or dielectric layers are subjected (e.g., during heat cycle testing due to the different thermal expansion characteristics of the substrate and the metal structure attached to the substrate) and avoid cracks or breaks therein. This results in improved reliability and mechanical ruggedness of the packaged acoustic wave components200-400, optionally with any of the variants ofFIG.6or7. Such temperature performance advantageously allows use of the packaged acoustic wave components200-400for high power applications (e.g., in a high power transmit filter). It also allows for a size reduction in the packaged acoustic wave component200-400, as described above, optionally with any of the variants ofFIG.6or7.

An MPS acoustic wave resonator or device or die in a packaged acoustic wave component, including any suitable combination of features disclosed herein, can be included in a filter arranged to filter a radio frequency signal in a fifth generation (5G) New Radio (NR) operating band within Frequency Range 1 (FR1). A filter arranged to filter a radio frequency signal in a 5G NR operating band can include one or more MPS acoustic wave resonators disclosed herein. FR1 can be from 410 MHz to 7.125 GHz, for example, as specified in a current 5G NR specification. In 5G applications, the thermal dissipation of the MPS acoustic wave resonators disclosed herein can be advantageous. For example, such thermal dissipation can be desirable in 5G applications with a higher time-division duplexing (TDD) duty cycle compared to fourth generation (4G) Long Term Evolution (LTE). One or more MPS acoustic wave resonators in accordance with any suitable principles and advantages disclosed herein can be included in a filter arranged to filter a radio frequency signal in a 4G LTE operating band and/or in a filter having a passband that includes a 4G LTE operating band and a 5G NR operating band.

FIG.9Ais a schematic diagram of an example transmit filter101that includes surface acoustic wave resonators according to an embodiment. The transmit filter101can be a band pass filter. The illustrated transmit filter101is arranged to filter a radio frequency signal received at a transmit port TX and provide a filtered output signal to an antenna port ANT. Some or all of the SAW resonators TS1to TS7and/or TP1to TP5can be a SAW resonator in accordance with any suitable principles and advantages disclosed herein. For instance, one or more of the SAW resonators of the transmit filter101can be part of one or more of the packaged acoustic wave components such as the packaged acoustic wave components200-400ofFIGS.2-4, optionally with any of the variants ofFIG.6or7. Any suitable number of series SAW resonators and shunt SAW resonators can be included in a transmit filter101.

FIG.9Bis a schematic diagram of a receive filter105that includes surface acoustic wave resonators according to an embodiment. The receive filter105can be a band pass filter. The illustrated receive filter105is arranged to filter a radio frequency signal received at an antenna port ANT and provide a filtered output signal to a receive port RX. Some or all of the SAW resonators RS1to RS8and/or RP1to RP6can be SAW resonators included in a packaged acoustic wave component in accordance with any suitable principles and advantages disclosed herein. For instance, one or more of the SAW resonators of the receive filter105can be part of one or more of the packaged acoustic wave components200-400, optionally with any of the variants ofFIG.6or7. Any suitable number of series SAW resonators and shunt SAW resonators can be included in a receive filter105.

AlthoughFIGS.9A and9Billustrate example ladder filter topologies, any suitable filter topology can include a SAW resonator in accordance with any suitable principles and advantages disclosed herein. Example filter topologies include a ladder topology, a lattice topology, a hybrid ladder and lattice topology, a multi-mode SAW filter, a multi-mode SAW filter combined with one or more other SAW resonators, and the like.

FIG.10is a schematic diagram of a radio frequency module175that includes a surface acoustic wave component176according to an embodiment. The illustrated radio frequency module175includes the SAW component176and other circuitry177. The SAW component176can include one or more SAW resonators with any suitable combination of features of the SAW resonators or packages disclosed herein. The SAW component176can include a SAW die that includes SAW resonators.

The SAW component176shown inFIG.10includes a filter178and terminals179A and179B. The filter178includes SAW resonators. One or more of the SAW resonators can be implemented in accordance with any suitable principles and advantages of the packaged acoustic wave components200-400, optionally with any of the variants ofFIG.6or7. The terminals179A and178B can serve, for example, as an input contact and an output contact. The SAW component176and the other circuitry177are on the same packaging substrate180inFIG.10. The package substrate180can be a laminate substrate. The terminals179A and179B can be electrically connected to contacts181A and181B, respectively, on the packaging substrate180by way of electrical connectors182A and182B, respectively. The electrical connectors182A and182B can be bumps or wire bonds, for example. The other circuitry177can include any suitable additional circuitry. For example, the other circuitry can include one or more one or more power amplifiers, one or more radio frequency switches, one or more additional filters, one or more low noise amplifiers, the like, or any suitable combination thereof. The radio frequency module175can include one or more packaging structures to, for example, provide protection and/or facilitate easier handling of the radio frequency module175. Such a packaging structure can include an overmold structure formed over the packaging substrate180. The overmold structure can encapsulate some or all of the components of the radio frequency module175.

FIG.11is a schematic diagram of a radio frequency module184that includes a surface acoustic wave resonator according to an embodiment. As illustrated, the radio frequency module184includes duplexers185A to185N that include respective transmit filters186A1to186N1and respective receive filters186A2to186N2, a power amplifier187, a select switch188, and an antenna switch189. In some instances, the module184can include one or more low noise amplifiers configured to receive a signal from one or more receive filters of the receive filters186A2to186N2. The radio frequency module184can include a package that encloses the illustrated elements. The illustrated elements can be disposed on the same packaging substrate180. The packaging substrate can be a laminate substrate, for example.

The duplexers185A to185N can each include two acoustic wave filters coupled to a common node. The two acoustic wave filters can be a transmit filter and a receive filter. As illustrated, the transmit filter and the receive filter can each be band pass filters arranged to filter a radio frequency signal. One or more of the transmit filters186A1to186N1can include one or more SAW resonators or packages in accordance with any suitable principles and advantages disclosed herein. Similarly, one or more of the receive filters186A2to186N2can include one or more SAW resonators in accordance with any suitable principles and advantages disclosed herein. AlthoughFIG.11illustrates duplexers, any suitable principles and advantages disclosed herein can be implemented in other multiplexers (e.g., quadplexers, hexaplexers, octoplexers, etc.) and/or in switch-plexers and/or to standalone filters.

The power amplifier187can amplify a radio frequency signal. The illustrated switch188is a multi-throw radio frequency switch. The switch188can electrically couple an output of the power amplifier187to a selected transmit filter of the transmit filters186A1to186N1. In some instances, the switch188can electrically connect the output of the power amplifier187to more than one of the transmit filters186A1to186N1. The antenna switch189can selectively couple a signal from one or more of the duplexers185A to185N to an antenna port ANT. The duplexers185A to185N can be associated with different frequency bands and/or different modes of operation (e.g., different power modes, different signaling modes, etc.).

FIG.12is a schematic block diagram of a module190that includes duplexers191A to191N and an antenna switch192. One or more filters of the duplexers191A to191N can include any suitable number of surface acoustic wave resonators or packages in accordance with any suitable principles and advantages discussed herein. Any suitable number of duplexers191A to191N can be implemented. The antenna switch192can have a number of throws corresponding to the number of duplexers191A to191N. The antenna switch192can electrically couple a selected duplexer to an antenna port of the module190.

FIG.13Ais a schematic block diagram of a module410that includes a power amplifier412, a radio frequency switch414, and duplexers191A to191N in accordance with one or more embodiments. The power amplifier412can amplify a radio frequency signal. The radio frequency switch414can be a multi-throw radio frequency switch. The radio frequency switch414can electrically couple an output of the power amplifier412to a selected transmit filter of the duplexers191A to191N. One or more filters of the duplexers191A to191N can include any suitable number of surface acoustic wave resonators or packages in accordance with any suitable principles and advantages discussed herein. Any suitable number of duplexers191A to191N can be implemented.

FIG.13Bis a schematic block diagram of a module415that includes filters416A to416N, a radio frequency switch417, and a low noise amplifier418according to an embodiment. One or more filters of the filters416A to416N can include any suitable number of acoustic wave resonators or packages in accordance with any suitable principles and advantages disclosed herein. Any suitable number of filters416A to416N can be implemented. The illustrated filters416A to416N are receive filters. In some embodiments (not illustrated), one or more of the filters416A to416N can be included in a multiplexer that also includes a transmit filter. The radio frequency switch417can be a multi-throw radio frequency switch. The radio frequency switch417can electrically couple an output of a selected filter of filters416A to416N to the low noise amplifier418. In some embodiments (not illustrated), a plurality of low noise amplifiers can be implemented. The module415can include diversity receive features in certain applications.

FIG.14Ais a schematic diagram of a wireless communication device420that includes filters423in a radio frequency front end422according to an embodiment. The filters423can include one or more SAW resonators or packages in accordance with any suitable principles and advantages discussed herein. The wireless communication device420can be any suitable wireless communication device. For instance, a wireless communication device420can be a mobile phone, such as a smart phone. As illustrated, the wireless communication device420includes an antenna421, an RF front end422, a transceiver424, a processor425, a memory426, and a user interface427. The antenna421can transmit/receive RF signals provided by the RF front end422. Such RF signals can include carrier aggregation signals. Although not illustrated, the wireless communication device420can include a microphone and a speaker in certain embodiments.

The RF front end422can include one or more power amplifiers, one or more low noise amplifiers, one or more RF switches, one or more receive filters, one or more transmit filters, one or more duplex filters, one or more multiplexers, one or more frequency multiplexing circuits, the like, or any suitable combination thereof. The RF front end422can transmit and receive RF signals associated with any suitable communication standards. The filters423can include SAW resonators of a SAW component or package that includes any suitable combination of features discussed with reference to any embodiments discussed above.

The transceiver424can provide RF signals to the RF front end422for amplification and/or other processing. The transceiver424can also process an RF signal provided by a low noise amplifier of the RF front end422. The transceiver424is in communication with the processor425. The processor425can be a base band processor. The processor425can provide any suitable base band processing functions for the wireless communication device420. The memory426can be accessed by the processor425. The memory426can store any suitable data for the wireless communication device420. The user interface427can be any suitable user interface, such as a display with touch screen capabilities.

FIG.14Bis a schematic diagram of a wireless communication device430that includes filters423in a radio frequency front end422and second filters433in a diversity receive module432. The wireless communication device430is like the wireless communication device420ofFIG.14A, except that the wireless communication device430also includes diversity receive features. As illustrated inFIG.14B, the wireless communication device430includes a diversity antenna431, a diversity module432configured to process signals received by the diversity antenna431and including filters433, and a transceiver434in communication with both the radio frequency front end422and the diversity receive module432. The filters433can include one or more SAW resonators or packaged acoustic wave components that include any suitable combination of features discussed with reference to any embodiments discussed above.

Although embodiments disclosed herein relate to surface acoustic wave resonators or packages and packaged acoustic wave components, any suitable principles and advantages disclosed herein can be applied to other types of acoustic wave resonators that include an IDT electrode, such as Lamb wave resonators and/or boundary wave resonators.

Any of the embodiments described above can be implemented in association with mobile devices such as cellular handsets. The principles and advantages of the embodiments can be used for any systems or apparatus, such as any uplink wireless communication device, that could benefit from any of the embodiments described herein. The teachings herein are applicable to a variety of systems. Although this disclosure includes some example embodiments, the teachings described herein can be applied to a variety of structures. Any of the principles and advantages discussed herein can be implemented in association with RF circuits configured to process signals in a frequency range from about 30 kHz to 300 GHz, such as in a frequency range from about 450 MHz to 8.5 GHz. Acoustic wave resonators and/or filters disclosed herein can filter RF signals at frequencies up to and including millimeter wave frequencies.

Aspects of this disclosure can be implemented in various electronic devices. Examples of the electronic devices can include, but are not limited to, consumer electronic products, parts of the consumer electronic products such as packaged radio frequency modules and/or packaged filter components, uplink wireless communication devices, wireless communication infrastructure, electronic test equipment, etc. Examples of the electronic devices can include, but are not limited to, a mobile phone such as a smart phone, a wearable computing device such as a smart watch or an ear piece, a telephone, a television, a computer monitor, a computer, a modem, a hand-held computer, a laptop computer, a tablet computer, a microwave, a refrigerator, a vehicular electronics system such as an automotive electronics system, a stereo system, a digital music player, a radio, a camera such as a digital camera, a portable memory chip, a washer, a dryer, a washer/dryer, a copier, a facsimile machine, a scanner, a multi-functional peripheral device, a wrist watch, a clock, etc. Further, the electronic devices can include unfinished products.