Bulk acoustic wave resonator filter and bulk acoustic wave resonator package

Abstract

The present disclosure provides a bulk acoustic wave resonator filter and a bulk acoustic wave resonator package. The bulk acoustic wave resonator filter includes a series part including at least one series acoustic resonator electrically connected between a first radio frequency port and a second radio frequency port, and a plurality of shunt acoustic resonators electrically connected in series with each other between a first node of the series part and a first ground port, wherein each of the plurality of shunt acoustic resonators includes a resonant part including a first electrode, a piezoelectric layer, and a second electrode, the first electrode, the piezoelectric layer, and the second electrode of the resonant part of each of the plurality of shunt acoustic resonators are stacked in a stacking area, an aspect ratio of the stacking area is equal to a ratio between a longest length of the stacking area in an extension direction of a longest side of the stacking area and a longest length of the stacking area in a direction perpendicular to the extension direction, and the aspect ratios of the plurality of shunt acoustic resonators include different aspect ratios.

Description

[0001] This application claims the benefit of priority to Korean Patent Application No. 10-2021-0131853, filed on October 5, 2021, with the Korean Intellectual Property Office, and Korean Patent Application No. 10-2022-0033164, filed on March 17, 2022, with the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference for all purposes. Technical Field

[0002] This disclosure relates to a bulk acoustic wave resonator filter and a bulk acoustic wave resonator package. Background Technology

[0003] Recently, with the rapid development of mobile communication devices and chemical and biological testing devices, the demand for small and lightweight filters, oscillators, resonant elements, and acoustic resonant quality sensors used in these devices is increasing.

[0004] Acoustic resonators, such as bulk acoustic wave (BAW) filters, can be configured to realize small and lightweight filters, oscillators, resonant elements, and acoustic resonant quality sensors, and can have relatively small size and relatively good performance compared to dielectric filters, metallic cavity filters, and waveguides. Therefore, acoustic resonators can be widely used in communication modules of modern mobile devices that require relatively good performance (e.g., relatively wide bandwidth). Summary of the Invention

[0005] This summary is provided to introduce selected concepts in a simplified form, and these concepts are further described in the following detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used to help determine the scope of the claimed subject matter.

[0006] In one general aspect, a bulk acoustic resonator filter includes: a series section including at least one series acoustic resonator electrically connected in series between a first radio frequency port and a second radio frequency port; and a plurality of shunt acoustic resonators electrically connected in series with each other between a first node of the series section and a first ground port, wherein each of the plurality of shunt acoustic resonators includes a resonant section including a first electrode, a piezoelectric layer and a second electrode stacked in a first direction, the first electrode, the piezoelectric layer and the second electrode of the resonant section of each of the plurality of shunt acoustic resonators being stacked in a stacked region, the aspect ratio of the stacked region of each of the plurality of shunt acoustic resonators being equal to the ratio between the longest length of the stacked region in the direction of extension of the longest side of the stacked region and the longest length of the stacked region in a direction perpendicular to the extension direction, and the aspect ratios of the plurality of shunt acoustic resonators including different aspect ratios.

[0007] The difference between the different aspect ratios of the plurality of shunt acoustic resonators can reduce the difference in anti-resonance frequencies among the plurality of shunt acoustic resonators.

[0008] The difference in anti-resonance frequency among the plurality of shunt acoustic resonators can be less than the difference in resonance frequency among the plurality of shunt acoustic resonators.

[0009] The plurality of shunt acoustic resonators can be connected to each other through corresponding first electrodes or corresponding second electrodes, and the aspect ratio difference between the plurality of shunt acoustic resonators can increase as the connection length between the plurality of shunt acoustic resonators increases.

[0010] The aspect ratio of the shunt acoustic resonator closest to the first ground port electrical connection among the plurality of shunt acoustic resonators may be lower than the aspect ratio of the shunt acoustic resonator further away from the first ground port electrical connection among the plurality of shunt acoustic resonators.

[0011] The aspect ratio of the shunt acoustic resonator that is further away from the first grounding port electrical connection can be in the range of 2.2 to 2.6.

[0012] The aspect ratio of each of the plurality of shunt acoustic resonators may be greater than 1.3 and less than or equal to 6.6.

[0013] The aspect ratio of each of the plurality of shunt acoustic resonators may be greater than 1.3 and less than 3.8.

[0014] Each of the at least one series acoustic resonator may include: a resonant portion comprising a first electrode, a piezoelectric layer, and a second electrode stacked in the first direction, wherein the first electrode, piezoelectric layer, and second electrode of the resonant portion of each of the at least one series acoustic resonator are stacked on top of each other in a stacked region, wherein the aspect ratio of the stacked region of each of the at least one series acoustic resonator may be equal to the ratio between the longest length of the stacked region in the extension direction of the longest side of the stacked region and the longest length of the stacked region in the direction perpendicular to the extension direction, and the symmetry of the shape of the stacked region of at least one of the plurality of shunt acoustic resonators may be higher than the symmetry of the shape of the stacked region of at least one of the at least one series acoustic resonator.

[0015] The aspect ratio of at least one of the plurality of shunt acoustic resonators may be greater than or equal to 4.8 and less than or equal to 6.6.

[0016] The symmetry of the shape of the stacked region of the plurality of shunt acoustic resonators may include different symmetries, and the aspect ratio of the shunt acoustic resonator with higher symmetry among the plurality of shunt acoustic resonators may be higher than the aspect ratio of the shunt acoustic resonator with lower symmetry among the plurality of shunt acoustic resonators.

[0017] The aspect ratio of the shunt acoustic resonator with higher symmetry can be greater than or equal to 4.8 and less than or equal to 6.6, and the aspect ratio of the shunt acoustic resonator with lower symmetry can be greater than 1.3 and less than 3.8.

[0018] The plurality of shunt acoustic resonators may include a first shunt acoustic resonator, a second shunt acoustic resonator, and a third shunt acoustic resonator connected in series. The first shunt acoustic resonator and the second shunt acoustic resonator may be connected to each other through a corresponding first electrode or a corresponding second electrode. The second shunt acoustic resonator and the third shunt acoustic resonator may be connected to each other through a corresponding first electrode or a corresponding second electrode. The aspect ratio difference between the first shunt acoustic resonator and the second shunt acoustic resonator may be different from the aspect ratio difference between the second shunt acoustic resonator and the third shunt acoustic resonator.

[0019] The plurality of shunt acoustic resonators may include a first shunt acoustic resonator and a second shunt acoustic resonator connected in series with each other between the first node of the series section and the first ground port. The plurality of shunt acoustic resonators may also include a third shunt acoustic resonator and a fourth shunt acoustic resonator connected in series with each other between the first node of the series section and the first ground port. Each of the third and fourth shunt acoustic resonators may include: a resonant section comprising a first electrode, a piezoelectric layer, and a second electrode stacked in the first direction. In each of the fourth shunt acoustic resonators, the first electrode, piezoelectric layer, and second electrode of the resonant section are stacked on top of each other in the stacked region. The aspect ratio of the stacked region of each of the third and fourth shunt acoustic resonators is equal to the ratio between the longest length of the stacked region in the extension direction of the longest side of the stacked region and the longest length of the stacked region in the direction perpendicular to the extension direction. The first and second shunt acoustic resonators, which are connected in series with each other, can be connected in parallel with the third and fourth shunt acoustic resonators, which are connected in series with each other.

[0020] One of the first shunt acoustic resonators and the third shunt acoustic resonator can be electrically connected to the first ground port through the first electrode of the first shunt acoustic resonator, and the other shunt acoustic resonator can be electrically connected to the first ground port through the second electrode of the other shunt acoustic resonator.

[0021] The aspect ratios of the third and fourth shunt acoustic resonators may be different from each other, and the aspect ratio difference between the first and second shunt acoustic resonators may be different from the aspect ratio difference between the third and fourth shunt acoustic resonators.

[0022] The bulk acoustic wave resonator filter may further include a fifth shunt acoustic wave resonator and a sixth shunt acoustic wave resonator connected in series between the second node of the series section and the second ground port. Each of the fifth shunt acoustic wave resonator and the sixth shunt acoustic wave resonator may include a resonant section comprising a first electrode, a piezoelectric layer, and a second electrode stacked in the first direction. The first electrode, piezoelectric layer, and second electrode of the resonant section of each of the fifth shunt acoustic wave resonator and the sixth shunt acoustic wave resonator are stacked in a stacked region. The aspect ratio of the stacked region of each of the fifth shunt acoustic wave resonator and the sixth shunt acoustic wave resonator may be equal to the ratio between the longest length of the stacked region in the extension direction of the longest side of the stacked region and the longest length of the stacked region in the direction perpendicular to the extension direction. The at least one series acoustic resonator may include a series acoustic resonator electrically connected between the first node and the second node. Compared with the second shunt acoustic resonator and the fourth shunt acoustic resonator, the first shunt acoustic resonator and the third shunt acoustic resonator may be electrically connected closer to the first ground port. Compared with the sixth shunt acoustic resonator, the fifth shunt acoustic resonator may be electrically connected closer to the second ground port. The size of the stacked region of each of the first shunt acoustic resonator and the third shunt acoustic resonator may be different from the size of the stacked region of the fifth shunt acoustic resonator. The size of the stacked region of each of the second shunt acoustic resonator and the fourth shunt acoustic resonator may be different from the size of the stacked region of the sixth shunt acoustic resonator.

[0023] In another general aspect, a bulk acoustic resonator filter includes: a series section comprising at least one series acoustic resonator electrically connected in series between a first radio frequency port and a second radio frequency port; and a shunt section comprising a plurality of shunt acoustic resonators electrically connected between the series section and ground, wherein each of the plurality of shunt acoustic resonators includes a resonant section comprising a first electrode, a piezoelectric layer, and a second electrode stacked in a first direction, the first electrode, the piezoelectric layer, and the second electrode of the resonant section of each of the plurality of shunt acoustic resonators being stacked on top of each other in a stacked region, the plurality of shunt acoustic resonators... The aspect ratio of each of the stacked regions is equal to the ratio between the longest length of the stacked region in the direction of extension of the longest side of the stacked region and the longest length of the stacked region in the direction perpendicular to the extension direction. The first portion of the plurality of shunt acoustic resonators is electrically connected to ground through a first electrode, and the second portion of the plurality of shunt acoustic resonators is electrically connected to ground through a second electrode. The aspect ratio of the first portion of the plurality of shunt acoustic resonators electrically connected to ground through the first electrode is different from the aspect ratio of the second portion of the plurality of shunt acoustic resonators electrically connected to ground through the second electrode.

[0024] The difference between the aspect ratio of the first portion of the plurality of shunt acoustic resonators electrically connected to ground via the first electrode and the aspect ratio of the second portion of the plurality of shunt acoustic resonators electrically connected to ground via the second electrode can reduce the difference in anti-resonance frequency among the plurality of shunt acoustic resonators.

[0025] The difference in anti-resonance frequency between the first portion of the plurality of shunt acoustic resonators electrically connected to ground via a first electrode and the second portion of the plurality of shunt acoustic resonators electrically connected to ground via a second electrode can be less than the difference in resonance frequency between the first portion of the plurality of shunt acoustic resonators electrically connected to ground via a first electrode and the second portion of the plurality of shunt acoustic resonators electrically connected to ground via a second electrode.

[0026] The resonant frequency of the at least one series acoustic resonator may be higher than the resonant frequency of each of the plurality of shunt acoustic resonators, and the difference in resonant frequency between the first portion of the plurality of shunt acoustic resonators electrically connected to ground via a first electrode and the second portion of the plurality of shunt acoustic resonators electrically connected to ground via a second electrode may be less than the difference in resonant frequency between the highest resonant frequency of the plurality of shunt acoustic resonators and the resonant frequency of the at least one series acoustic resonator.

[0027] The first portion of the plurality of shunt acoustic resonators electrically connected to ground via a first electrode and the second portion of the plurality of shunt acoustic resonators electrically connected to ground via a second electrode can be electrically connected between the first node of the series section and the grounding port.

[0028] In another general aspect, a bulk acoustic wave resonator package includes: a substrate; a cover facing the substrate; a plurality of acoustic wave resonators, each of the plurality of acoustic wave resonators including a first electrode, a piezoelectric layer, and a second electrode forming a resonant portion, the first electrode, the piezoelectric layer, and the second electrode being stacked in a first direction extending from the substrate toward the cover, the first electrode, the piezoelectric layer, and the second electrode being stacked in a stacked region and disposed between the substrate and the cover; a metal layer connecting the plurality of acoustic wave resonators to each other; and a bonding member surrounding the plurality of acoustic wave resonators in a circumferential direction perpendicular to the first direction and bonding the cover to the substrate, wherein the aspect ratio of the stacked region of each of the plurality of acoustic wave resonators is equal to the ratio between the longest length of the stacked region in the direction extending along the longest side of the stacked region and the longest length of the stacked region in the direction perpendicular to the extension direction, and the aspect ratio of the acoustic wave resonator disposed closer to the bonding member is lower than the aspect ratio of the other acoustic wave resonators disposed further away from the bonding member.

[0029] The aspect ratio difference between two acoustic resonators in the plurality of acoustic resonators can increase as the connection length of the metal layer connecting the two acoustic resonators to each other increases.

[0030] The aspect ratio difference between two acoustic resonators in the plurality of acoustic resonators can increase as the spacing between the metal layer connecting the two acoustic resonators to each other and the bonding member decreases.

[0031] The plurality of acoustic resonators may include a first acoustic resonator, a second acoustic resonator, a third acoustic resonator, and a fourth acoustic resonator. The first acoustic resonator and the second acoustic resonator may be connected to each other through a first portion of the metal layer, and the third acoustic resonator and the fourth acoustic resonator may be connected to each other through a second portion of the metal layer. The connection length of the first portion of the metal layer connecting the first acoustic resonator and the second acoustic resonator may be longer than the connection length of the second portion of the metal layer connecting the third acoustic resonator and the fourth acoustic resonator. Furthermore, the aspect ratio difference between the first acoustic resonator and the second acoustic resonator may be greater than the aspect ratio difference between the third acoustic resonator and the fourth acoustic resonator.

[0032] The plurality of acoustic resonators may include a first acoustic resonator, a second acoustic resonator, a third acoustic resonator, and a fourth acoustic resonator. The first acoustic resonator and the second acoustic resonator may be connected to each other through a first portion of the metal layer, and the third acoustic resonator and the fourth acoustic resonator may be connected to each other through a second portion of the metal layer. The spacing between the first portion of the metal layer connecting the first acoustic resonator and the second acoustic resonator and the bonding member may be shorter than the spacing between the second portion of the metal layer connecting the third acoustic resonator and the fourth acoustic resonator and the bonding member. Furthermore, the aspect ratio difference between the first acoustic resonator and the second acoustic resonator may be greater than the aspect ratio difference between the third acoustic resonator and the fourth acoustic resonator.

[0033] The plurality of acoustic resonators may include a first acoustic resonator, a second acoustic resonator, a third acoustic resonator, and a fourth acoustic resonator. The first acoustic resonator and the second acoustic resonator may be connected to each other through a first portion of the metal layer, and the third acoustic resonator and the fourth acoustic resonator may be connected to each other through a second portion of the metal layer. The first portion of the metal layer connecting the first acoustic resonator and the second acoustic resonator and the second portion of the metal layer connecting the third acoustic resonator and the fourth acoustic resonator may be disposed at different heights relative to the substrate, and the aspect ratios of the first acoustic resonator and the second acoustic resonator may be different from each other.

[0034] The plurality of acoustic resonators may include a first acoustic resonator, a second acoustic resonator, and a third acoustic resonator connected in series with each other. Among the first acoustic resonator, the second acoustic resonator, and the third acoustic resonator, the first acoustic resonator may be closest to the bonding member, and the aspect ratio difference between the first acoustic resonator and the second acoustic resonator may be greater than the aspect ratio difference between the second acoustic resonator and the third acoustic resonator.

[0035] The bulk acoustic wave resonator package may further include a first radio frequency (RF) port and a second RF port. The plurality of acoustic wave resonators may be electrically connected to the first RF port and the second RF port through the metal layer. The first RF port may be disposed near a first side of the substrate, and the second RF port may be disposed near a second side of the substrate. The aspect ratio of the acoustic wave resonator disposed closer to the third side of the substrate may be lower than the aspect ratio of the other acoustic wave resonators disposed further away from the third side of the substrate.

[0036] The bulk acoustic resonator package may further include a ground port, through which the plurality of acoustic resonators are electrically connected to the ground port via the metal layer, wherein the aspect ratio of the acoustic resonator closer to the ground port may be lower than the aspect ratio of the other acoustic resonators further away from the ground port.

[0037] The joining member may include a conductive ring.

[0038] The bulk acoustic resonator package may further include a shielding layer disposed on the surface of the cover facing the plurality of acoustic resonators and electrically connected to the bonding member.

[0039] In another general aspect, a bulk acoustic resonator filter includes: a series section comprising at least one series acoustic resonator electrically connected in series between a first radio frequency port and a second radio frequency port; and a plurality of shunt acoustic resonators electrically connected to each other between nodes of the series section and a ground port, wherein each of the plurality of shunt acoustic resonators may include a resonant section comprising a first electrode, a piezoelectric layer, and a second electrode stacked in a first direction, the first electrode, the piezoelectric layer, and the second electrode of the resonant section of each of the plurality of shunt acoustic resonators being stacked on top of each other in a stacked region, the aspect ratio of the stacked region of each of the plurality of shunt acoustic resonators being equal to the longest length of the stacked region in the direction of extension of the longest side of the stacked region and the length of the stacked region. The bulk acoustic resonator filter further includes: a first metal layer electrically connected to a first electrode of the plurality of shunt acoustic resonators; and a second metal layer electrically connected to a second electrode of the plurality of shunt acoustic resonators, the plurality of shunt acoustic resonators including a first shunt acoustic resonator and a second shunt acoustic resonator electrically connected to each other in an anti-series connection, wherein the second metal layer electrically connects the second electrode of the first shunt acoustic resonator to the ground port, and the first metal layer electrically connects the first electrode of the second shunt acoustic resonator to the first electrode of the first shunt acoustic resonator, and the aspect ratio of the second shunt acoustic resonator is different from that of the first shunt acoustic resonator.

[0040] The difference in aspect ratio between the first shunt acoustic resonator and the second shunt acoustic resonator can offset the difference in parasitic impedance between the first shunt acoustic resonator and the second shunt acoustic resonator.

[0041] The aspect ratio of the second shunt acoustic resonator can be higher than that of the first shunt acoustic resonator.

[0042] The aspect ratio of the second shunt acoustic resonator may be lower than that of the first shunt acoustic resonator.

[0043] The plurality of shunt acoustic resonators may further include a third shunt acoustic resonator and a fourth shunt acoustic resonator electrically connected to each other in an anti-series connection manner, wherein a portion of the first metal layer electrically connects the first electrode of the third shunt acoustic resonator to the second metal layer, and the second metal layer electrically connects the portion of the first metal layer to the ground port, and the second metal layer electrically connects the second electrode of the fourth shunt acoustic resonator to the second electrode of the third shunt acoustic resonator, and the aspect ratio of the fourth shunt acoustic resonator may be equal to or substantially equal to the aspect ratio of the third shunt acoustic resonator.

[0044] In another general aspect, a bulk acoustic resonator filter includes: a series section comprising at least one series acoustic resonator electrically connected in series between a first radio frequency port and a second radio frequency port; and a plurality of shunt acoustic resonators electrically connected in parallel between each other between a first node of the series section and a first ground port, wherein each of the plurality of shunt acoustic resonators includes a resonant section comprising a first electrode, a piezoelectric layer, and a second electrode stacked in a first direction, the first electrode, the piezoelectric layer, and the second electrode of the resonant section of each of the plurality of shunt acoustic resonators being stacked in a stacked region, the aspect ratio of the stacked region of each of the plurality of shunt acoustic resonators being equal to the longest length of the stacked region in the direction of extension of the longest side of the stacked region and the length of the stacked region in a direction perpendicular to the extension direction. The ratio between the longest lengths, the bulk acoustic resonator filter may further include: a first metal layer electrically connected to a first electrode of the plurality of shunt acoustic resonators; and a second metal layer electrically connected to a second electrode of the plurality of shunt acoustic resonators, the plurality of shunt acoustic resonators including a first shunt acoustic resonator and a second shunt acoustic resonator electrically connected to each other in an anti-parallel connection, wherein the second metal layer electrically connects the second electrode of the first shunt acoustic resonator to a first ground port, and a portion of the first metal layer electrically connects the first electrode of the second shunt acoustic resonator to the second metal layer, and the second metal layer electrically connects the portion of the first metal layer to the first ground port, and the aspect ratio of the second shunt acoustic resonator is different from that of the first shunt acoustic resonator.

[0045] The difference in aspect ratio between the first shunt acoustic resonator and the second shunt acoustic resonator can offset the difference in parasitic impedance between the first shunt acoustic resonator and the second shunt acoustic resonator.

[0046] The aspect ratio of the second shunt acoustic resonator can be higher than that of the first shunt acoustic resonator.

[0047] The bulk acoustic resonator filter may further include a second plurality of shunt acoustic resonators electrically connected in series between the second node of the series section and the second ground port. Each of the second plurality of shunt acoustic resonators may include a resonant section comprising a first electrode, a piezoelectric layer, and a second electrode stacked in the first direction. The first electrode, piezoelectric layer, and second electrode of the resonant section of each of the second plurality of shunt acoustic resonators are stacked in a stacked region. The aspect ratio of the stacked region of each of the second plurality of shunt acoustic resonators may be equal to the ratio between the longest length of the stacked region in the extension direction of the longest side of the stacked region and the longest length of the stacked region in the direction perpendicular to the extension direction. The at least one series acoustic resonator may include a component electrically connected to the first... The first metal layer is electrically connected to the first electrode of the second plurality of shunt acoustic resonators, and the second metal layer is also electrically connected to the second electrode of the second plurality of shunt acoustic resonators. The second plurality of shunt acoustic resonators may further include a third shunt acoustic resonator and a fourth shunt acoustic resonator electrically connected to each other in an anti-series connection manner. The second metal layer electrically connects the second electrode of the third shunt acoustic resonator to the second ground port, and the first metal layer electrically connects the first electrode of the fourth shunt acoustic resonator to the first electrode of the third shunt acoustic resonator. The aspect ratio of the fourth shunt acoustic resonator may be equal to or substantially equal to the aspect ratio of the third shunt acoustic resonator.

[0048] Other features and aspects will be readily understood from the following detailed description and accompanying drawings. Attached Figure Description

[0049] Figures 1A to 1C This is a perspective view illustrating a bulk acoustic resonator filter / package according to an embodiment of the present disclosure.

[0050] Figure 1D This is a perspective view showing a structure in which a bulk acoustic resonator filter / package is disposed on a substrate according to an embodiment of the present disclosure.

[0051] Figure 1E This is a circuit diagram illustrating a bulk acoustic resonator filter according to an embodiment of the present disclosure.

[0052] Figures 2A to 2G This is a plan view illustrating various variations of the bulk acoustic resonator filter / package according to embodiments of the present disclosure.

[0053] Figures 3A to 3HThis is a circuit diagram illustrating various variations of the bulk acoustic resonator filter structure according to embodiments of the present disclosure.

[0054] Figure 4A This is a plan view showing the variation of the aspect ratio of the acoustic resonator of the bulk acoustic resonator filter / package according to an embodiment of the present disclosure.

[0055] Figure 4B It shows the basis Figure 4A A graph showing the change in the anti-resonance frequency of an acoustic resonator due to the change in its aspect ratio.

[0056] Figure 4C This illustrates the change in aspect ratio of the shunt acoustic resonator as it is connected to the closest or joint component, through... Figure 3H The graph shows the power variation of the shunt acoustic resonator.

[0057] Figure 4D It shows the basis Figure 4C The power variations of the multiple shunt acoustic resonators shown are achieved through... Figure 3H A graph showing the power variation of multiple shunt acoustic resonators.

[0058] Figure 4E It shows the basis Figure 4D The power variations of the multiple shunt acoustic resonators shown are achieved through... Figure 3H A graph showing the amplitude of the second harmonic in the signal of multiple shunt acoustic resonators.

[0059] Figure 4F It is shown that the size is greater than Figure 3H When the aspect ratio of the shunt acoustic resonators closest to each other decreases, the size of the shunt acoustic resonators decreases. Figure 3H A graph showing the amplitude of the second harmonic in the signal of multiple shunt acoustic resonators.

[0060] Figure 4G It is shown Figure 3H The bandwidth curve of the bulk acoustic resonator filter.

[0061] Figure 5A This is a view showing aspect ratio measurements of various types of acoustic resonators according to embodiments of the present disclosure, in a bulk acoustic resonator filter / package.

[0062] Figure 5B This is a view illustrating asymmetrical and symmetrical structures of a bulk acoustic resonator resonator filter / package according to embodiments of the present disclosure.

[0063] Figure 5CThis is a view showing that the aspect ratio can be changed according to the connection length between multiple shunt acoustic resonators of a bulk acoustic resonator filter / package according to an embodiment of the present disclosure.

[0064] Figure 6A This is a plan view illustrating a specific structure of an acoustic resonator that may be included in a bulk acoustic resonator filter / package according to an embodiment of the present disclosure. Figure 6B It is along Figure 6A A cross-sectional view taken from line VIB-VIB' in the diagram. Figure 6C It is along Figure 6A The cross-sectional view taken by line VIC-VIC' in the diagram, and Figure 6D It is along Figure 6A The cross-sectional view taken from line VID-VID' in the diagram.

[0065] Figure 6E and Figure 6F This is a cross-sectional view showing the structure of the internal and external spaces of an electrical connector acoustic resonator filter / package according to an embodiment of the present disclosure.

[0066] Throughout the accompanying drawings and detailed embodiments, the same reference numerals indicate the same elements. The drawings may not be drawn to scale, and for clarity, illustration, and convenience, the relative sizes, scales, and depictions of the elements in the drawings may be exaggerated. Detailed Implementation

[0067] The following detailed embodiments are provided to aid the reader in gaining a comprehensive understanding of the methods, apparatus, and / or systems described herein. However, after understanding the disclosure of this application, various changes, modifications, and equivalents of the methods, apparatus, and / or systems described herein will be readily apparent. For example, the order of operations described herein is merely illustrative and is not limited to the order set forth herein; rather, changes that will be readily understood after understanding the disclosure of this application are possible, except for operations that must occur in a specific order. Furthermore, for clarity and brevity, descriptions of features known in the art may be omitted.

[0068] The features described herein may be implemented in different forms and shall not be construed as being limited to the examples described herein. Rather, the examples described herein have been provided merely to illustrate some of the many feasible ways of implementing the methods, apparatus, and / or systems described herein that will be readily understood upon understanding the disclosure of this application.

[0069] Throughout the specification, when an element such as a layer, region, or substrate is described as being "on" another element, "connected to" another element, or "bonded to" another element, that element may be directly "on" another element, directly "connected to" another element, or directly "bonded to" another element, or there may be one or more other elements in between. In contrast, when an element is described as being "directly on" another element, "directly connected to" another element, or "directly bonded to" another element, there are no other elements in between.

[0070] As used herein, the term "and / or" includes any one or any combination of any two or more of the associated listed items.

[0071] Although terms such as “first,” “second,” and “third” may be used herein to describe various components, assemblies, regions, layers, or parts, these components, assemblies, regions, layers, or parts will not be limited by these terms. Rather, these terms are used only to distinguish one component, assembly, region, layer, or part from another. Therefore, without departing from the teaching of the examples described herein, the first component, first assembly, first region, first layer, or first part referred to as the first component, first assembly, first region, first layer, or first part may also be referred to as the second component, second assembly, second region, second layer, or second part.

[0072] For ease of description, spatial relative terms such as “above,” “above,” “below,” and “under” are used herein to describe the relationship between one element and another, as shown in the accompanying drawings. Such spatial relative terms are intended to include not only the orientation depicted in the drawings but also different orientations of the device during use or operation. For example, if the device in the drawings is flipped, an element described as “above” or “above” relative to another element will then be “below” or “under” relative to said other element. Therefore, the term “above” includes both “above” and “below” orientations depending on the spatial orientation of the device. The device may also be positioned in other ways (e.g., rotated 90 degrees or in other orientations), and the spatial relative terms used herein will be interpreted accordingly.

[0073] The terminology used herein is for the purpose of describing various examples only and is not intended to limit this disclosure. Unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. The terms “comprising,” “including,” and “having” enumerate the presence of the stated features, quantities, operations, components, elements, and / or combinations thereof, but do not exclude the presence or addition of one or more other features, quantities, operations, components, elements, and / or combinations thereof.

[0074] Figures 1A to 1CThis is a perspective view illustrating a bulk acoustic resonator filter / package according to an embodiment of the present disclosure. Figure 1D This is a perspective view showing a structure according to an embodiment of the present disclosure in which a bulk acoustic resonator filter / package is disposed on a substrate, and Figure 1E This is a circuit diagram illustrating a bulk acoustic resonator filter according to an embodiment of the present disclosure.

[0075] Reference Figures 1A to 1E According to an embodiment of the present disclosure, the bulk acoustic resonator filter 50 may include a series section 10 and a shunt section 20, and may transmit or block radio frequency (RF) signals between a first RF port P1 and a second RF port P2 according to the frequency of the RF signal.

[0076] The series section 10 may include at least one series acoustic resonator 11, 12, 13 and 14, and the shunt section 20 may include a plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a and 23b.

[0077] The plurality of nodes N1, N2 and N3 disposed between at least one series acoustic resonator 11, 12, 13 and 14, between a plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a and 23b, and between the series section 10 and the shunt section 20 may be implemented using materials with relatively low resistivity (such as gold (Au), gold-tin (Au-Sn) alloy, copper (Cu), copper-tin (Cu-Sn) alloy, aluminum (Al) or aluminum alloy), but this disclosure is not limited thereto.

[0078] At least one of the series acoustic resonators 11, 12, 13, and 14, and each of the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b, can convert electrical energy of an RF signal into mechanical energy, or vice versa, through the piezoelectric effect. As the frequency of the RF signal approaches the resonant frequency of each of the acoustic resonators, the energy transfer rate between the electrodes increases. As the frequency of the RF signal approaches the anti-resonant frequency of each of the acoustic resonators, the energy transfer rate between the electrodes decreases. The anti-resonant frequency of each of the acoustic resonators can be higher than the resonant frequency of each of the acoustic resonators.

[0079] For example, each of at least one series acoustic resonator 11, 12, 13 and 14 and each of the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a and 23b may be a thin-film bulk acoustic resonator (FBAR) or a solid-state assembled resonator (SMR).

[0080] At least one series acoustic resonator 11, 12, 13, and 14 may be connected in series between the first RF port P1 and the second RF port P2. As the frequency of the RF signal approaches the resonant frequency, the transmittance of the RF signal between the first RF port P1 and the second RF port P2 increases. As the frequency of the RF signal approaches the anti-resonant frequency, the transmittance of the RF signal between the first RF port P1 and the second RF port P2 decreases.

[0081] Multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b can be connected in parallel between at least one series acoustic resonator 11, 12, 13, and 14 and ground GND. As the frequency of the RF signal approaches the resonant frequency, the transmittance of the RF signal towards ground GND increases. As the frequency of the RF signal approaches the anti-resonant frequency, the transmittance of the RF signal towards ground GND decreases.

[0082] The transmittance of the RF signal between the first RF port P1 and the second RF port P2 decreases as the transmittance of the RF signal towards ground (GND) increases. Conversely, the transmittance of the RF signal between the first RF port P1 and the second RF port P2 increases as the transmittance of the RF signal towards ground (GND) decreases.

[0083] For example, as the frequency of the RF signal approaches the resonant frequency of each of the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a and 23b or the anti-resonant frequency of each of at least one series acoustic resonator 11, 12, 13 and 14, the transmittance of the RF signal between the first RF port P1 and the second RF port P2 decreases.

[0084] Since the anti-resonant frequency is higher than the resonant frequency, the bulk acoustic resonator filter 50 according to an embodiment of the present disclosure may have a passband formed by a lowest frequency corresponding to the resonant frequencies of the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a and 23b and a highest frequency corresponding to the anti-resonant frequency of at least one series acoustic resonator 11, 12, 13 and 14. Optionally, the bulk acoustic resonator filter 50 according to an embodiment of the present disclosure may have a stopband formed by a lowest frequency corresponding to the resonant frequencies of at least one series acoustic resonator 11, 12, 13 and 14 and a highest frequency corresponding to the anti-resonant frequencies of the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a and 23b.

[0085] The pass bandwidth increases with the increasing difference between the resonant frequency of each of the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b and the anti-resonant frequency of each of at least one series acoustic resonator 11, 12, 13, and 14. The stop bandwidth increases with the increasing difference between the resonant frequency of each of the at least one series acoustic resonator 11, 12, 13, and 14 and the anti-resonant frequency of each of the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b. When the difference is too large, the bandwidth may be segmented, and the insertion loss and / or return loss of the bandwidth may increase.

[0086] When the resonant frequency of each of at least one of the series acoustic resonators 11, 12, 13 and 14 is appropriately higher than the anti-resonant frequency of each of the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a and 23b, or when the resonant frequency of each of the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a and 23b is appropriately higher than the anti-resonant frequency of each of at least one of the series acoustic resonators 11, 12, 13 and 14, the bandwidth of the bulk acoustic resonator filter 50 may be wide and unsegmented, or the loss of the bulk acoustic resonator filter 50 may be reduced.

[0087] In an acoustic resonator, K can be based on the physical characteristics of the acoustic resonator. t 2 The electromechanical coupling factor is used to determine the difference between the resonant frequency and the anti-resonant frequency, and K can be determined based on the size, thickness, and shape of the acoustic resonator. t 2 .

[0088] Since the bandwidth of the bulk acoustic resonator filter 50 is proportional to the total frequency of the bandwidth, the bandwidth can increase as the total frequency of the bandwidth increases.

[0089] As the total frequency of the bandwidth increases, the wavelength of the RF signal passing through the bulk acoustic resonator filter 50 decreases. Under the same transmission / reception distance during remote transmission / reception via antenna, energy attenuation increases as the wavelength of the RF signal decreases.

[0090] For example, as the total frequency of the bandwidth of the bulk acoustic resonator filter 50 increases, the RF signal passing through the bulk acoustic resonator filter 50 may require higher power in order to ensure the stability and / or smoothness of the remote transmission / reception process.

[0091] As the power of the RF signal passing through the bulk acoustic resonator filter 50 increases, the heat generated by the piezoelectric operation of each of the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a and 23b and at least one of the series acoustic resonators 11, 12, 13 and 14 increases, and the possibility of each of the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a and 23b and at least one of the series acoustic resonators 11, 12, 13 and 14 being damaged due to heat increases.

[0092] As the number (e.g., 8) of the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a and 23b included in the shunt section 20 increases, or the ratio (e.g., 8 / 3) of the number of the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a and 23b to the number of the plurality of nodes N1, N2 and N3 increases, the heat generated by the piezoelectric operation of each of the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a and 23b decreases, and the likelihood of each of the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a and 23b being damaged due to heat decreases.

[0093] Even when the number of shunt acoustic resonators included in the shunt section 20 is only one, the bandwidth can be formed based on a combination of one shunt acoustic resonator and one series acoustic resonator. Since the bulk acoustic resonator filter 50 according to the embodiments of this disclosure may include at least two of a plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a and 23b, the frequency of the RF signal and the power of the RF signal can be effectively increased.

[0094] Furthermore, since the bulk acoustic resonator filter 50 according to embodiments of the present disclosure may include a plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a and 23b, the following additional advantages can be obtained (e.g., improved linearity and attenuation characteristics).

[0095] For example, each of the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b can be connected to the first electrode of an adjacent shunt acoustic resonator via the first electrode of each of the plurality of shunt acoustic resonators (e.g., an electrode disposed on the lower surface of the piezoelectric layer), or can be connected to the second electrode of an adjacent shunt acoustic resonator via the second electrode of each of the plurality of shunt acoustic resonators (e.g., an electrode disposed on the upper surface of the piezoelectric layer). Therefore, each of the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b can be connected to an adjacent shunt acoustic resonator in an anti-series connection manner, and the anti-series connection structure can be used by increasing the number of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b.

[0096] In a series connection, the first electrode of the shunt acoustic resonator is connected to the second electrode of the adjacent shunt acoustic resonator, or the second electrode of the shunt acoustic resonator is connected to the first electrode of the adjacent shunt acoustic resonator.

[0097] In an anti-series connection, the first electrode of the shunt acoustic resonator is connected to the first electrode of the adjacent shunt acoustic resonator, or the second electrode of the shunt acoustic resonator is connected to the second electrode of the adjacent shunt acoustic resonator.

[0098] Therefore, since the multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a and 23b can effectively cancel the even harmonics of the RF signal, the linear characteristics of the bulk acoustic resonator filter 50 (e.g., second-order intermodulation distortion (IMD2), 1dB compression point (P1dB) and total harmonic distortion (THD)) can be improved more effectively, and the bulk acoustic resonator filter 50 can effectively conform to the communication standard to which the frequency of the RF signal belongs.

[0099] For example, the resonant frequencies and / or anti-resonant frequencies of some of the multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b may differ from the resonant frequencies and / or anti-resonant frequencies of the other shunt acoustic resonators. The difference in the resonant frequencies and / or anti-resonant frequencies of the multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b can be increased by increasing the number of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b. The difference in anti-resonant frequencies among the multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b can be smaller than the difference in resonant frequencies among the multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b.

[0100] Therefore, multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b can optimize the positions of multiple resonant frequencies and / or multiple anti-resonant frequencies near the minimum frequency of the bandwidth of the bulk acoustic resonator filter 50, making the attenuation characteristics of the bulk acoustic resonator filter 50 sharper and effectively removing parasitic noise that may be generated near the minimum frequency due to the characteristics of the acoustic resonator. For example, a combination of multiple resonant frequencies and / or multiple anti-resonant frequencies can form transmission zeros and poles in the frequency characteristics of the bulk acoustic resonator filter 50 to further improve the attenuation characteristics of the bulk acoustic resonator filter 50.

[0101] Since the difference between the design characteristics and actual characteristics of each of the multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b can affect the performance of the bulk acoustic resonator filter 50 (e.g., loss characteristics, frequency limiting characteristics, maximum power characteristics, heating characteristics, linearity characteristics, attenuation characteristics, or other characteristics), as the number of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b included in the shunt section 20 (e.g., 8) increases or the ratio of the number of multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b to the number of multiple nodes N1, N2, and N3 (e.g., 8 / 3) increases, reducing the difference between the design characteristics and actual characteristics of each of the multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b may become more important.

[0102] The difference between the design characteristics and actual characteristics of each of the multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b may depend on the parasitic impedance of each of the multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b. Even if the peripheral conductive structure of each of the multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b is not electrically connected to the multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b, parasitic impedance may still be generated based on the electric field and / or magnetic field between the peripheral conductive structures of the multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b.

[0103] For example, the peripheral conductive structure capable of influencing parasitic impedance may be at least one of the following components: a plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a and 23b, metal layers 1180 and 1190 connecting the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a and 23b to each other, a grounding port 1320 providing ground GND for the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a and 23b, a bonding member 1220 bonding the substrate 1110 and the cover 1210 to each other, and a shielding layer 1230 disposed on the cover 1210.

[0104] Because various factors affect parasitic impedance, the parasitic impedances of multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b can differ from each other. For example, some of the multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b that are electrically connected in series may have different parasitic impedances due to differences in how they are arranged relative to ground (GND).

[0105] For example, in a plurality of shunt acoustic resonators, the metal layers 1180 and 1190 between the first shunt acoustic resonators 21a, 22a, and 23a and the second shunt acoustic resonators 21b, 22b, and 23b may together with at least one of the ground port 1320, the bonding member 1220, and the shielding layer 1230 to form a parasitic capacitor Cpara. The parasitic capacitor Cpara may function in a manner similar to a capacitor connected in parallel with the first shunt acoustic resonators 21a, 22a, and 23a, and may be part of the parasitic impedance of the first shunt acoustic resonators 21a, 22a, and 23a, and may have substantially no effect on the parasitic impedance of the second shunt acoustic resonators 21b, 22b, and 23b. Therefore, the parasitic impedance of the first shunt acoustic resonators 21a, 22a, and 23a may differ from the parasitic impedance of the second shunt acoustic resonators 21b, 22b, and 23b.

[0106] The bulk acoustic wave resonator filter 50 and the bulk acoustic wave resonator package according to embodiments of the present disclosure may include a plurality of shunt acoustic wave resonators 21a, 21b, 22a, 22b, 23a and 23b with different aspect ratios (see also...). Figure 4A and Figure 5A The AR in the middle can reduce the total parasitic impedance difference among the multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a and 23b without increasing the capacitor connected in parallel with the second shunt acoustic resonators 21b, 22b and 23b.

[0107] Therefore, since the difference between the design characteristics and actual characteristics of each of the multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b can be effectively reduced, the bulk acoustic resonator filter 50 and bulk acoustic resonator package according to embodiments of the present disclosure can use multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b to effectively improve their performance (e.g., loss characteristics, frequency limiting characteristics, maximum power characteristics, heating characteristics, linearity characteristics, attenuation characteristics, or other characteristics). Furthermore, since additional capacitors for reducing the total parasitic impedance difference of the multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b are not required, the bulk acoustic resonator filter 50 and bulk acoustic resonator package according to embodiments of the present disclosure can have high performance within the same size.

[0108] K can be based on the physical characteristics of the corresponding acoustic resonator. t 2 (Electromechanical coupling factor) is used to determine the difference between the resonant frequency and the anti-resonant frequency of each of the multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b, and the K of the corresponding acoustic resonator. t 2 It can be changed according to the aspect ratio of the corresponding acoustic resonator.

[0109] For example, the aspect ratio of each of the first shunt acoustic resonators 21a, 22a, and 23a may be lower than that of each of the second shunt acoustic resonators 21b, 22b, and 23b. This makes the difference between the resonant frequency and the anti-resonant frequency of each of the first shunt acoustic resonators 21a, 22a, and 23a greater than the difference between the resonant frequency and the anti-resonant frequency of each of the second shunt acoustic resonators 21b, 22b, and 23b. Setting the resonant frequencies of the first shunt acoustic resonators 21a, 22a, and 23a to be equal to the resonant frequencies of the second shunt acoustic resonators 21b, 22b, and 23b allows the anti-resonant frequency of each of the first shunt acoustic resonators 21a, 22a, and 23a to be higher than the anti-resonant frequency of each of the second shunt acoustic resonators 21b, 22b, and 23b.

[0110] Furthermore, based on the equivalent circuit of each of the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b, in each of the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b, the series LC equivalent component that is proportional to the resonant frequency may be different from the parallel LC equivalent component that is inversely proportional to the anti-resonant frequency. The parasitic capacitor Cpara, which can be used as a parallel capacitor relative to the first shunt acoustic resonators 21a, 22a, and 23a, can be the C equivalent component of the parallel LC equivalent component that is inversely proportional to the anti-resonant frequency of the first shunt acoustic resonators 21a, 22a, and 23a. Therefore, the anti-resonant frequency of the first shunt acoustic resonators 21a, 22a, and 23a with parasitic capacitor Cpara may be lower than the anti-resonant frequency of the first shunt acoustic resonators 21a, 22a, and 23a without parasitic capacitor Cpara.

[0111] Therefore, by reducing the anti-resonance frequencies of the first shunt acoustic resonators 21a, 22a, and 23a through the parasitic capacitor Cpara, and by increasing the anti-resonance frequencies of the first shunt acoustic resonators 21a, 22a, and 23a through their low aspect ratio, they can cancel each other out, effectively reducing the difference between the anti-resonance frequencies of the first shunt acoustic resonators 21a, 22a, and 23a and the anti-resonance frequencies of the second shunt acoustic resonators 21b, 22b, and 23b. This effectively improves the performance (e.g., loss characteristics, frequency limiting characteristics, maximum power characteristics, heat generation characteristics, linearity characteristics, attenuation characteristics, or other characteristics) of the bulk acoustic resonator filter 50 and the bulk acoustic resonator package according to embodiments of this disclosure.

[0112] As the aspect ratio of each of at least one series acoustic resonator 11, 12, 13, and 14 and each of the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b increases, the connection width between each of the at least one series acoustic resonator 11, 12, 13, and 14 and each of the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b and each of the metal layers 1180 and 1190 connected thereto can be increased. Therefore, the connection resistance of each of the metal layers 1180 and 1190 relative to the at least one series acoustic resonator 11, 12, 13, and 14 and the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b decreases. As the total connection resistance decreases, the energy loss of the bulk acoustic resonator filter 50 and the bulk acoustic resonator package according to embodiments of the present disclosure decreases.

[0113] Therefore, the aspect ratio of each of the first shunt acoustic resonators 21a, 22a, and 23a, which is closer to the ground (GND) electrical connection than the second shunt acoustic resonators 21b, 22b, and 23b, can be lower than that of each of the second shunt acoustic resonators 21b, 22b, and 23b. For example, the aspect ratio of each of the first shunt acoustic resonators 21a, 22a, and 23a can be closer to 1 and relatively closer to a regular polygon compared to the aspect ratio of each of the second shunt acoustic resonators 21b, 22b, and 23b.

[0114] The capacitance of the parasitic capacitor Cpara increases with the length of each of the metal layers 1180 and 1190 that connect the first shunt acoustic resonators 21a, 22a, and 23a to the second shunt acoustic resonators 21b, 22b, and 23b. Therefore, the aspect ratio difference between the first shunt acoustic resonators 21a, 22a, and 23a and the second shunt acoustic resonators 21b, 22b, and 23b increases with the increase of the connection length between the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, and 23b.

[0115] Reference Figures 1A to 1C According to embodiments of the present disclosure, a bulk acoustic resonator package may include a substrate 1110, a cover 1210, a plurality of acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a and 23b, metal layers 1180 and 1190, and a bonding member 1220, and may also include a first RF port P1, a second RF port P2, a ground port 1320, a film layer 1150 and a shielding layer 1230.

[0116] The substrate 1110 may have cavities formed beneath a plurality of acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b. When the bulk acoustic resonator is a solid-state assembled resonator (SMR), the bulk acoustic resonator may have a stacked structure in place of alternating heterogeneous layers with different acoustic impedances instead of cavities.

[0117] The film layer 1150 may be disposed between the cavity or stack structure and the plurality of acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a and 23b, and may serve as the substantial upper surface of the substrate 1110.

[0118] The cover 1210 can accommodate multiple acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b to protect them from the influence of the external environment. The cover 1210 can be formed as a covering portion having an internal space therein accommodating the multiple acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b. For example, the cover 1210 can have a shape in which the portion adjacent to the edge of the lower surface of the cover 1210 facing the substrate 1110 protrudes further toward the substrate 1110 than the central portion of the lower surface. For example, the vertical cross-section of the cover 1210 can be U-shaped.

[0119] Each of the plurality of acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a and 23b may include a first electrode, a piezoelectric layer and a second electrode stacked on a first direction (e.g., the Z direction) in which the substrate 1110 and the cover 1210 face each other, and may be accommodated between the substrate 1110 and the cover 1210.

[0120] Metal layers 1180 and 1190 can connect to a plurality of acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b. Metal layer 1180 can be connected to the first electrode (e.g., an electrode disposed on the lower surface of the piezoelectric layer) of the plurality of acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b, and metal layer 1190 can be connected to the second electrode (e.g., an electrode disposed on the upper surface of the piezoelectric layer) of the plurality of acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b. Therefore, metal layers 1180 and 1190 can be disposed at different heights relative to the substrate, and the parasitic impedance caused by metal layer 1180 and the parasitic impedance caused by metal layer 1190 can be different from each other.

[0121] The bonding member 1220 may surround a plurality of acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b in a circumferential direction perpendicular to a first direction (e.g., the Z direction), and may be bonded to the cover 1210 between the substrate 1110 and the cover 1210. For example, the bonding member 1220 may have a eutectic bonding structure and may therefore include a conductive ring. The bonding member 1220 is not limited to a eutectic bonding structure and may also be implemented as an anodic bonding structure or a fusion bonding structure of non-conductive materials.

[0122] Metal layers 1180 and 1190 and bonding member 1220 can form a parasitic capacitor Cpara. This parasitic capacitor Cpara may affect only a portion of the multiple acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b, or it may affect the multiple acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b differently. Therefore, due to the parasitic capacitor Cpara based on metal layers 1180 and 1190 and bonding member 1220, the total parasitic impedance difference among the multiple acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b may increase.

[0123] In the bulk acoustic resonator package according to embodiments of the present disclosure, at least two of the plurality of acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b may have different aspect ratios relative to each other. Therefore, the total parasitic impedance difference among the plurality of acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b can be reduced, and the difference between the design characteristics and actual characteristics of each of the plurality of acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b can be effectively reduced.

[0124] The parasitic capacitor Cpara based on metal layers 1180 and 1190 and bonding member 1220 may increase with the length of metal layers 1180 and 1190, or with metal layers 1180 and 1190 being positioned closer to bonding member 1220. For example, the parasitic capacitor Cpara may increase with the increase of the connection length of metal layers 1180 and 1190 connecting multiple acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a and 23b to each other, or with the decrease of the spacing between metal layers 1180 and 1190 and bonding member 1220.

[0125] To reduce the parasitic impedance differences among the multiple acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b, the aspect ratio differences among the multiple acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b can increase as the connection length of the metal layers 1180 and 1190 connecting the multiple acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, and 23a increases, or as the spacing between the metal layers 1180 and 1190 and the bonding member 1220 decreases.

[0126] For example, the first acoustic resonator 21a and the second acoustic resonator 21b can be connected to each other through a first portion of the metal layer 1180, and the third acoustic resonators 22a and 23a and the fourth acoustic resonators 22b and 23b can be connected to each other through a second portion of the metal layer 1180. The connection length of the first portion of the metal layer 1180 connecting the first acoustic resonator 21a and the second acoustic resonator 21b can be longer than the connection length of the second portion of the metal layer 1180 connecting the third acoustic resonators 22a and 23a and the fourth acoustic resonators 22b and 23b. The spacing between the first portion of the metal layer 1180 connecting the first acoustic resonator 21a and the second acoustic resonator 21b and the bonding member 1220 can be shorter than the spacing between the second portion of the metal layer 1180 connecting the third acoustic resonators 22a and 23a and the fourth acoustic resonators 22b and 23b and the bonding member 1220. The aspect ratio difference between the first acoustic resonator 21a and the second acoustic resonator 21b can be greater than the aspect ratio difference between the third acoustic resonators 22a and 23a and the fourth acoustic resonators 22b and 23b.

[0127] As the aspect ratio of each of the plurality of acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b increases, the connection width between each of the plurality of acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b and the metal layers 1180 and 1190 connected thereto increases. Therefore, the connection resistance of each of the metal layers 1180 and 1190 relative to the plurality of acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b decreases. With the decrease in total connection resistance, the energy loss of the bulk acoustic resonator package according to embodiments of the present disclosure decreases.

[0128] Therefore, the aspect ratio of each of the acoustic resonators 11, 12, 13, 14, 21b, 22b, and 23b disposed relatively far from the joining member 1220 can be relatively high, and the aspect ratio of each of the acoustic resonators 21a, 22a, and 23a disposed relatively closer to the joining member 1220 can be relatively lower than the aspect ratio of each of the acoustic resonators 11, 12, 13, 14, 21b, 22b, and 23b. For example, the aspect ratio of each of the acoustic resonators 21a, 22a, and 23a can be closer to 1 than the aspect ratio of each of the acoustic resonators 11, 12, 13, 14, 21b, 22b, and 23b.

[0129] Multiple acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b are electrically connected between a first RF port P1 and a second RF port P2. The first RF port P1 may be located near a first side surface of the substrate 1110 (e.g., in the -Y direction away from the center of the substrate 1110), and the second RF port P2 may be located near a second side surface of the substrate 1110 (e.g., in the +Y direction away from the center of the substrate 1110). The first RF port P1 and the second RF port P2 provide a vertical electrical connection path between the interior and exterior of the bulk acoustic resonator package.

[0130] Since the first RF port P1 and the second RF port P2 can be located near the first and second side surfaces of the substrate 1110 (e.g., in the -Y and +Y directions away from the center of the substrate 1110), the ground port 1320 can be located near the third side surface of the substrate 1110 (e.g., in the -X direction away from the center of the substrate 1110) and / or near the fourth side surface of the substrate 1110 (e.g., in the +X direction away from the center of the substrate 1110).

[0131] Ground port 1320 can provide ground (GND), and the capacitance of the parasitic capacitor Cpara based on metal layers 1180 and 1190 and bonding member 1220 can depend on the location of ground port 1320. Therefore, the aspect ratio of each of the acoustic resonators 21a, 22a, and 23a that is located closer to the third and / or fourth side surface of substrate 1110 than the acoustic resonators 11, 12, 13, 14, 21b, 22b, and 23b, or that is located closer to ground port 1320 than the acoustic resonators 11, 12, 13, 14, 21b, 22b, and 23b, can be relatively lower than the aspect ratio of each of the acoustic resonators 11, 12, 13, 14, 21b, 22b, and 23b. For example, the aspect ratios of acoustic resonators 21a, 22a, and 23a are closer to 1 than the aspect ratios of each of acoustic resonators 11, 12, 13, 14, 21b, 22b, and 23b.

[0132] A shielding layer 1230 may be disposed on a surface (e.g., the lower surface) of the cover 1210 facing the plurality of acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b, and may be electrically connected to the bonding member 1220. The shielding layer 1230 suppresses electromagnetic noise received by the plurality of acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b from outside the bulk acoustic resonator package. Therefore, the performance of the bulk acoustic resonator package can be improved.

[0133] Since the shielding layer 1230 can be stacked with the metal layers 1180 and 1190 in the Z direction and can be electrically connected to ground (GND), the shielding layer 1230, as well as the metal layers 1180 and 1190, can be used as part of the parasitic capacitor Cpara. As described above, the parasitic impedance difference caused by the parasitic capacitor Cpara between the individual acoustic resonators of the plurality of acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b can be reduced due to the aspect ratio difference between the individual acoustic resonators of the plurality of acoustic resonators 11, 12, 13, 14, 21a, 21b, 22a, 22b, 23a, and 23b.

[0134] Reference Figure 1D According to embodiments of the present disclosure, the bulk acoustic wave resonator filter 50 and the bulk acoustic wave resonator package may be disposed (e.g., mounted or embedded) on the assembly substrate 90.

[0135] For example, the substrate 90 may be a printed circuit board in which multiple conductive layers and multiple insulating layers are stacked alternately, and the multiple conductive layers may include an antenna transmission path ANT, a transceiver transmission path SIG and ground GND, and multiple vias VIA may electrically connect the multiple conductive layers to each other in the Z direction.

[0136] The antenna transmission path ANT can be electrically connected to Figures 1A to 1C The first RF port P1, and the transceiver transmission path SIG can be electrically connected to Figures 1A to 1C The second RF port P2. When the bulk acoustic resonator filter 50 according to an embodiment of the present disclosure is configured to filter the transmitted RF signal, the power of the RF signal transmitted through the second RF port P2 can be greater than the power of the RF signal transmitted through the first RF port P1. Therefore, the size of the shunt acoustic resonator closest to the second RF port P2 among the plurality of shunt acoustic resonators can be larger than the size of the other shunt acoustic resonators in the plurality of shunt acoustic resonators to improve heat dissipation characteristics and / or reduce losses. Conversely, when the bulk acoustic resonator filter 50 is configured to filter the received RF signal, the size of the shunt acoustic resonator closest to the first RF port P1 among the plurality of shunt acoustic resonators can be larger than the size of the other shunt acoustic resonators in the plurality of shunt acoustic resonators to improve heat dissipation characteristics and / or reduce losses.

[0137] Figures 2A to 2G This is a plan view illustrating various variant structures of a bulk acoustic resonator filter / package according to embodiments of the present disclosure, and Figures 3A to 3H This is a circuit diagram illustrating various variations of the bulk acoustic resonator filter structure according to embodiments of the present disclosure.

[0138] Reference Figure 2A and Figure 3AAccording to embodiments of the present disclosure, the bulk acoustic resonator filter 50a may include at least one series acoustic resonator 11, 12, 13 and 14 and a plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, 23b, 24a and 24b, wherein at least two of the plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, 23b, 24a and 24b may have different aspect ratios from each other.

[0139] The aspect ratio difference among the multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a, 23b, 24a, and 24b can be greater than the aspect ratio difference between at least one series acoustic resonator 11, 12, 13, and 14 and the shunt acoustic resonators 21b, 22b, 23b, and 24b among the multiple shunt acoustic resonators. The shunt acoustic resonators 21b, 22b, 23b, and 24b have an aspect ratio closer to that of at least one series acoustic resonator 11, 12, 13, and 14. Since the aspect ratio of at least one series acoustic resonator 11, 12, 13, and 14 can be high, the width of the portions of metal layers 1180 and 1190 that connect the multiple series acoustic resonators 11, 12, 13, and 14 to each other can be increased, thereby reducing their connection resistance. Therefore, the loss of the RF signal transmitted between the first RF port P1 and the second RF port P2 can be reduced.

[0140] Multiple shunt acoustic resonators 21a, 21b, 22a, 22b, 23a and 23b can be electrically connected between ground ports GND1, GND2 and GND3 and multiple nodes N1, N2 and N3, and multiple shunt acoustic resonators 24a and 24b can be electrically connected between ground port GND4 and the first RF port P1.

[0141] Metal layer 1180 ( Figure 2A The cross-shading region between the various acoustic resonators in the layer can be connected between the first electrodes (e.g., electrodes disposed on the lower surface of the piezoelectric layer) of multiple adjacent acoustic resonators, and the metal layer 1190 ( Figure 2A The non-crossing shaded areas between the various acoustic resonators in the layer can be connected between the second electrodes (e.g., electrodes disposed on the upper surface of the piezoelectric layer) of a plurality of adjacent acoustic resonators. In addition, the metal layer 1190 can be connected to the bonding member 1220 via the grounding extension member 1185, and the grounding ports GND3 and GND5 can ground the bonding member 1220 via the grounding extension member 1185.

[0142] The first shunt acoustic resonator (the right shunt acoustic resonator of 22a) and the second shunt acoustic resonator (the right shunt acoustic resonator of 22b) are electrically connected in series with each other via the first electrode and the metal layer 1180. The third shunt acoustic resonator (the left shunt acoustic resonator of 22a) and the fourth shunt acoustic resonator (the left shunt acoustic resonator of 22b) are electrically connected in series with each other via the second electrode and the metal layer 1190. Since the first and third shunt acoustic resonators 22a can be connected in parallel with each other, the first shunt acoustic resonator (the right shunt acoustic resonator of 22a) is electrically connected to the ground port GND2 via the second electrode and the metal layer 1190, and the third shunt acoustic resonator (the left shunt acoustic resonator of 22a) is electrically connected to the ground port GND2 via the first electrode and the metal layers 1180 and 1190.

[0143] Therefore, since the number of shunt acoustic resonators electrically connected between a node between the multiple series acoustic resonators 11, 12, 13 and 14 and the ground port GND2 can be effectively increased, the first shunt acoustic resonator, the second shunt acoustic resonator, the third shunt acoustic resonator and the fourth shunt acoustic resonators 22a and 22b can more effectively increase the frequency of the RF signal, more effectively increase the power of the RF signal, and more effectively improve the linearity and / or attenuation characteristics of the bulk acoustic resonator filter 50a according to the embodiments of the present disclosure.

[0144] Compared to the metal layer 1190 connecting the third shunt acoustic resonator (the left shunt acoustic resonator of 22a) and the fourth shunt acoustic resonator (the left shunt acoustic resonator of 22b), the metal layer 1180 connecting the first shunt acoustic resonator (the right shunt acoustic resonator of 22a) and the second shunt acoustic resonator (the right shunt acoustic resonator of 22b) can be disposed at a lower height relative to the substrate 1110. Therefore, the parasitic impedance of the first shunt acoustic resonator (the right shunt acoustic resonator of 22a) can be different from the parasitic impedance of the third shunt acoustic resonator (the left shunt acoustic resonator of 22a).

[0145] The first shunt acoustic resonator (the right shunt acoustic resonator of 22a) and the second shunt acoustic resonator (the right shunt acoustic resonator of 22b) may have different aspect ratios relative to each other, or the third shunt acoustic resonator (the left shunt acoustic resonator of 22a) and the fourth shunt acoustic resonator (the left shunt acoustic resonator of 22b) may have different aspect ratios relative to each other. Therefore, since at least one of the parasitic impedance differences between the first and third shunt acoustic resonators 22a and the second and fourth shunt acoustic resonators 22b, and the parasitic impedance difference between the first shunt acoustic resonator and the third shunt acoustic resonator, can be reduced, the total parasitic impedance difference among the first shunt acoustic resonator, the second shunt acoustic resonator, the third shunt acoustic resonator, and the fourth shunt acoustic resonators 22a and 22b can be effectively reduced.

[0146] Therefore, the bulk acoustic resonator filter 50a according to the embodiments of this disclosure can effectively reduce the difference between the design characteristics and actual characteristics of each of the first shunt acoustic resonators, the second shunt acoustic resonators, the third shunt acoustic resonators, and the fourth shunt acoustic resonators 22a and 22b by increasing the number of the first shunt acoustic resonators, the second shunt acoustic resonators, the third shunt acoustic resonators, and the fourth shunt acoustic resonators 22a and 22b, and provide advantages (e.g., improved loss characteristics, frequency limiting characteristics, maximum power characteristics, heat generation characteristics, linearity characteristics, attenuation characteristics, or other characteristics) by increasing the number of the first shunt acoustic resonators, the second shunt acoustic resonators, the third shunt acoustic resonators, and the fourth shunt acoustic resonators 22a and 22b, while effectively eliminating disadvantages (sensitivity to the difference between design characteristics and actual characteristics).

[0147] According to the design, the aspect ratios of the first shunt acoustic resonator (the right shunt acoustic resonator of 22a) and the second shunt acoustic resonator (the right shunt acoustic resonator of 22b) can be different from each other, and the aspect ratios of the third shunt acoustic resonator (the left shunt acoustic resonator of 22a) and the fourth shunt acoustic resonator (the left shunt acoustic resonator of 22b) can be different from each other. Furthermore, the aspect ratio difference between the first shunt acoustic resonator (the right shunt acoustic resonator of 22a) and the second shunt acoustic resonator (the right shunt acoustic resonator of 22b) can be different from the aspect ratio difference between the third shunt acoustic resonator (the left shunt acoustic resonator of 22a) and the fourth shunt acoustic resonator (the left shunt acoustic resonator of 22b). Therefore, the bulk acoustic resonator filter 50a according to the embodiments of this disclosure can effectively reduce the difference between the design characteristics and actual characteristics of each of the first shunt acoustic resonator, the second shunt acoustic resonator, the third shunt acoustic resonator and the fourth shunt acoustic resonators 22a and 22b.

[0148] Reference Figure 2B and Figure 3B In the bulk acoustic resonator filter 50b according to an embodiment of the present disclosure, the aspect ratio difference between the first shunt acoustic resonator 22a and the second shunt acoustic resonator 22b electrically connected between the second node N2 and the ground port GND2 may be different from the aspect ratio difference between the third shunt acoustic resonator 21b electrically connected between the first node N1 and the ground port GND1 and the fourth shunt acoustic resonator 23b electrically connected between the third node N3 and the ground port GND3.

[0149] For example, the number of nodes per node (e.g., four) of the first shunt acoustic resonator 22a and the second shunt acoustic resonator 22b can be greater than the number of nodes per node (e.g., two) of the third shunt acoustic resonator 21b and the fourth shunt acoustic resonator 23b. Therefore, the effect of the parasitic impedance difference between the first shunt acoustic resonator 22a and the second shunt acoustic resonator 22b on the bulk acoustic resonator filter 50b can be greater than the effect of the parasitic impedance difference between the third shunt acoustic resonator 21b and the fourth shunt acoustic resonator 23b on the bulk acoustic resonator filter 50b. Consequently, the aspect ratio difference between the first shunt acoustic resonator 22a and the second shunt acoustic resonator 22b can be greater than the aspect ratio difference between the third shunt acoustic resonator 21b and the fourth shunt acoustic resonator 23b.

[0150] Reference Figure 2C and Figure 3C The bulk acoustic wave resonator filter 50c according to embodiments of the present disclosure may have a structure in which the aspect ratios of the first shunt acoustic wave resonator 22a and the second shunt acoustic wave resonator 22b connected in parallel may be different. For example, the first shunt acoustic wave resonator 22a and the second shunt acoustic wave resonator 22b with different aspect ratios are not limited to being connected in series, and the parasitic impedance difference between the first shunt acoustic wave resonator 22a and the second shunt acoustic wave resonator 22b connected in parallel may also occur due to factors such as differences in the peripheral structure (e.g., metal layers 1180 and 1190) between the first shunt acoustic wave resonator 22a and the second shunt acoustic wave resonator 22b, or variations in the manufacturing process of the bulk acoustic wave resonator filter 50c according to embodiments of the present disclosure. In the bulk acoustic resonator filter 50c according to an embodiment of the present disclosure, the parasitic impedance difference between the first shunt acoustic resonator 22a and the second shunt acoustic resonator 22b, which are connected in parallel, can be reduced by the aspect ratio difference between the first shunt acoustic resonator 22a and the second shunt acoustic resonator 22b.

[0151] For example, the first shunt acoustic resonator 22a can be electrically connected to the ground port GND2 via the metal layer 1190 and the second electrode disposed on the upper surface of the piezoelectric layer of the first shunt acoustic resonator 22a, and the second shunt acoustic resonator 22b can be electrically connected to the ground port GND2 via the metal layer 1180, the metal layer 1190 and the first electrode disposed on the lower surface of the piezoelectric layer of the second shunt acoustic resonator 22b. This is an anti-parallel connection because the second electrode of the first shunt acoustic resonator 22a is connected to the first electrode of the second shunt acoustic resonator 22b. In a parallel connection, the first electrode of the first shunt acoustic resonator 22a disposed on the lower surface of the piezoelectric layer of the first shunt acoustic resonator 22a would be connected to the first electrode of the second shunt acoustic resonator 22b.

[0152] Therefore, since the structures of the first shunt acoustic resonator 22a and the second shunt acoustic resonator 22b electrically connected to the ground port GND2 can be different from each other, the parasitic capacitances of the first shunt acoustic resonator 22a and the second shunt acoustic resonator 22b can be different. Since the first shunt acoustic resonator 22a and the second shunt acoustic resonator 22b can have different aspect ratios, the difference in parasitic capacitance between the first shunt acoustic resonator 22a and the second shunt acoustic resonator 22b can be canceled out. Therefore, the shunt acoustic resonators 21b, 22a, 22b, 23b, and 24b of the bulk acoustic resonator filter 50c according to the embodiments of this disclosure should not be construed as limited to being connected in series with adjacent shunt acoustic resonators.

[0153] Reference Figure 2D and Figure 3D According to an embodiment of this disclosure, the bulk acoustic resonator filter 50d may have the following structure: first shunt acoustic resonators 21a and 22a, having an aspect ratio closer to 1 than the second shunt acoustic resonators 21b and 22b, are configured to be further away from the ground ports GND1 and GND2 than the second shunt acoustic resonators 21b and 22b. Various factors determine the parasitic impedance of the shunt acoustic resonators, and the resonant frequencies and / or anti-resonant frequencies of the first shunt acoustic resonators 21a and 22a may be different from the resonant frequencies and / or anti-resonant frequencies of the second shunt acoustic resonators 21b and 22b. Therefore, it is also possible to use, according to design, the following structure: first shunt acoustic resonators 21a and 22a, having an aspect ratio closer to 1 than the second shunt acoustic resonators 21b and 22b, are configured to be further away from the ground ports GND1 and GND2 than the second shunt acoustic resonators 21b and 22b.

[0154] In addition, refer to Figure 3DIn the bulk acoustic resonator filter 50d according to an embodiment of the present disclosure, the dimensions (e.g., the area of ​​the stacked first electrode, piezoelectric layer, and second electrode) of the first shunt acoustic resonators 21a and 22a and the second shunt acoustic resonators 21b and 22b may be larger than the dimension of the third shunt acoustic resonator 23b and may be larger than the dimension of the fourth shunt acoustic resonator 24b. The first shunt acoustic resonator 21a and the second shunt acoustic resonator 21b may be electrically connected between the first node N1 and the ground port GND1, the first shunt acoustic resonator 22a and the second shunt acoustic resonator 22b may be electrically connected between the second node N2 and the ground port GND2, the third shunt acoustic resonator 23b may be electrically connected between the third node N3 and the ground port GND3, and the fourth shunt acoustic resonator 24b may be connected between the first RF port P1 and the ground port GND4.

[0155] Since the power of the RF signal transmitted through the first RF port P1 electrically connected to the antenna can be less than the power of the RF signal transmitted through the second RF port P2, the first shunt acoustic resonator 21a and the second shunt acoustic resonator 21b electrically connected between the first node N1, which is closer to the second RF port P2 and farther from the antenna, and the ground port GND1, and the first shunt acoustic resonator 22a and the second shunt acoustic resonator 22b electrically connected between the second node N2, which is closer to the second RF port P2 and farther from the antenna, and the ground port GND2, may require higher heat dissipation characteristics and / or maximum output characteristics than the third shunt acoustic resonator 23b and the fourth shunt acoustic resonator 24b. Therefore, for higher heat dissipation characteristics and / or maximum output characteristics, the first shunt acoustic resonators 21a and 22a and the second shunt acoustic resonators 21b and 22b can be implemented with larger dimensions than the third shunt acoustic resonator 23b and the fourth shunt acoustic resonator 24b.

[0156] Therefore, the parasitic impedance difference between the first shunt acoustic resonators 21a and 22a and the second shunt acoustic resonators 21b and 22b can be greater than the parasitic impedance difference between the third shunt acoustic resonators 23b, and can also be greater than the parasitic impedance difference between the fourth shunt acoustic resonators 24b.

[0157] To reduce the overall impedance difference among multiple shunt acoustic resonators, the aspect ratio difference between the first shunt acoustic resonators 21a and 22a and the second shunt acoustic resonators 21b and 22b can be greater than the aspect ratio difference among the third shunt acoustic resonators 23b, and can also be greater than the aspect ratio difference among the fourth shunt acoustic resonators 24b. However, in Figure 2D and Figure 3DIn this embodiment, there is no aspect ratio difference between the third shunt acoustic resonators 23b and no aspect ratio difference between the fourth shunt acoustic resonators 24b. That is, the two third shunt acoustic resonators 23b have the same aspect ratio as each other, and the two fourth shunt acoustic resonators 24b have the same aspect ratio as each other.

[0158] Reference Figure 2E In the bulk acoustic resonator filter 50e according to an embodiment of the present disclosure, among a plurality of shunt acoustic resonators, the aspect ratio of one shunt acoustic resonator 21a that is closer to the ground port GND1 or the bonding member 1220 than another shunt acoustic resonator 21b may be greater than 1, and the aspect ratio of another shunt acoustic resonator 21b that is further away from the ground port GND1 or the bonding member 1220 may also be greater than 1. For example, by design, the aspect ratio of one shunt acoustic resonator 21a that is closer to the ground port GND1 or the bonding member 1220 may not be close to 1 compared to the aspect ratio of another shunt acoustic resonator 21b that is further away from the ground port GND1 or the bonding member 1220, and may be the same as or substantially the same as the aspect ratio of another shunt acoustic resonator 21b that is further away from the ground port GND1 or the bonding member 1220.

[0159] Reference Figure 2F and Figure 3E According to embodiments of the present disclosure, the bulk acoustic resonator filter 50f may include a first shunt acoustic resonator 21a, a second shunt acoustic resonator 21b, a third shunt acoustic resonator 21b, and a fourth shunt acoustic resonator 21b connected in series with each other. The first shunt acoustic resonator 21a and the second shunt acoustic resonator 21b (right shunt acoustic resonator 21b) may be connected to each other via a first electrode and a metal layer 1180. The second shunt acoustic resonator 21b (right shunt acoustic resonator 21b) and the third shunt acoustic resonator 21b (middle shunt acoustic resonator 21b) may be connected to each other via a second electrode and a metal layer 1190. The third shunt acoustic resonator 21b (middle shunt acoustic resonator 21b) and the fourth shunt acoustic resonator 21b (left shunt acoustic resonator 21b) may be connected to each other via a first electrode and a metal layer 1180. The first shunt acoustic resonator 21a can be positioned closest to the joint member 1220.

[0160] Since the parasitic capacitor formed by the metal layers 1180 and 1190 and the bonding member 1220 can be used as a capacitor connected in parallel with the first shunt acoustic resonator 21a, the parasitic impedance difference between the first shunt acoustic resonator 21a and the second shunt acoustic resonator 21b (right shunt acoustic resonator 21b) can be greater than the parasitic impedance difference between the second shunt acoustic resonator (right shunt acoustic resonator 21b) and the third shunt acoustic resonator 21b (middle shunt acoustic resonator 21b), and can be greater than the parasitic impedance difference between the third shunt acoustic resonator 21b (middle shunt acoustic resonator 21b) and the fourth shunt acoustic resonator 21b (left shunt acoustic resonator 21b).

[0161] To reduce the parasitic impedance differences among the first shunt acoustic resonator 21a, the second shunt acoustic resonator 21b, the third shunt acoustic resonator 21b, and the fourth shunt acoustic resonator 21b, the aspect ratio difference between the first shunt acoustic resonator 21a and the second shunt acoustic resonator 21b (right shunt acoustic resonator 21b) can be greater than the aspect ratio difference between the second shunt acoustic resonator 21b (right shunt acoustic resonator 21b) and the third shunt acoustic resonator 21b (middle shunt acoustic resonator 21b), and can also be greater than the aspect ratio difference between the third shunt acoustic resonator 21b (middle shunt acoustic resonator 21b) and the fourth shunt acoustic resonator 21b (left shunt acoustic resonator 21b).

[0162] Reference Figure 2G The bulk acoustic resonator filter 50g according to embodiments of the present disclosure may include a plurality of series acoustic resonators 11, 12, 13 and 14 and a plurality of shunt acoustic resonators 21a, 21b, 22a, 22b, 23b, 24a and 24b, and may have very high maximum output performance and / or very high heat dissipation performance, and therefore may be used in large electronic devices or mounted electronic devices.

[0163] Reference Figure 3F In addition to the components included in the bulk acoustic resonator filter 50a according to the embodiments of the present disclosure, the bulk acoustic resonator filter 50h according to the embodiments of the present disclosure may also include an inductor 29 connected in series with a plurality of shunt acoustic resonators 22a, 22b, 24a and 24b.

[0164] Since the inductor 29 can be part of the L equivalent component of the series LC equivalent and can be inversely proportional to the resonant frequencies of the plurality of shunt acoustic resonators 22a, 22b, 24a and 24b, the resonant frequencies of the plurality of shunt acoustic resonators 22a, 22b, 24a and 24b can be reduced. The resonant frequencies and / or anti-resonant frequencies of the plurality of shunt acoustic resonators 22a, 22b, 24a and 24b can be different from the resonant frequencies and / or anti-resonant frequencies of the plurality of shunt acoustic resonators 21a, 21b, 23a and 23b. Furthermore, the bulk acoustic resonator filter 50h according to the embodiments of the present disclosure can effectively form a wider bandwidth and / or obtain sharper attenuation characteristics.

[0165] Reference Figure 3G ,and Figure 1E Compared to bulk acoustic resonator filters, the bulk acoustic resonator filter 50i according to embodiments of the present disclosure may have a simpler structure.

[0166] Reference Figure 3H ,and Figure 3G Compared to bulk acoustic resonator filters, the bulk acoustic resonator filter 50j according to embodiments of the present disclosure can have a simpler structure. As an example, multiple shunt acoustic resonators may include a first shunt acoustic resonator, a second shunt acoustic resonator, and a third shunt acoustic resonator electrically connected in series with each other. The first and second shunt acoustic resonators are connected to each other via corresponding first or second electrodes, and the second and third shunt acoustic resonators are connected to each other via corresponding first or second electrodes. The aspect ratio difference between the first and second shunt acoustic resonators is different from the aspect ratio difference between the second and third shunt acoustic resonators. Shunt acoustic resonators can be arranged between different nodes of the series connection and ground, and the aspect ratios of multiple shunt acoustic resonators between the same node and ground can be different. The aspect ratios of the shunt acoustic resonators indicated in black may be different from those indicated in white. The size of the stacked area of ​​the shunt acoustic resonator, indicated by black, can be different from the size of the stacked area of ​​the shunt acoustic resonator, indicated by white.

[0167] Figure 4A This is a plan view showing the variation of the aspect ratio of the acoustic resonator of the bulk acoustic resonator filter / package according to an embodiment of the present disclosure.

[0168] Reference Figure 4AThe aspect ratio ARa of the stacked region of the first acoustic resonator 21a may differ from the aspect ratio ARb of the stacked region of the second acoustic resonator 21b. The aspect ratio ARa can be the ratio between the longest length L1a of the stacked region along the extension direction of the longest side of the first acoustic resonator 21a and the longest length L2a of the stacked region in the direction perpendicular to the extension direction, and can be a low aspect ratio (low AR). The aspect ratio ARb can be the ratio between the longest length L1b of the stacked region along the extension direction of the longest side of the second acoustic resonator 21b and the longest length L2b of the stacked region in the direction perpendicular to the extension direction, and can be a high aspect ratio (high AR).

[0169] For aspect ratio measurement, a virtual rectangle sharing the longest side of the first acoustic resonator 21a and the second acoustic resonator 21b can be defined. The size of the virtual rectangle can be set such that the remaining sides of the virtual rectangle pass through the vertices of the first acoustic resonator 21a and the second acoustic resonator 21b.

[0170] Depending on the specific shapes of the first acoustic resonator 21a and the second acoustic resonator 21b, the length of the long side of the virtual rectangle can be either length L1a or L1b in the direction of extension of the longest side, and can be equal to or longer than the length of the longest side. The length of the short side of the virtual rectangle can be either length L2a or L2b in the direction perpendicular to the longest side.

[0171] Figure 4A The aspect ratios ARa and ARb shown can be 1.2 and 6 respectively, but are not limited to these.

[0172] To reduce unwanted characteristic differences between the first acoustic resonator 21a and the second acoustic resonator 21b, their areas can be made equal. For example, to adjust the aspect ratios ARa and ARb, the lengths of the longest sides of the first acoustic resonator 21a and the second acoustic resonator 21b can be adjusted first, and the lengths of the remaining sides of the first acoustic resonator 21a and the second acoustic resonator 21b can be adjusted to calculated lengths in response to the adjustment of the longest side, so that the areas of the first acoustic resonator 21a and the second acoustic resonator 21b remain the same.

[0173] Therefore, since the first acoustic resonator 21a and the second acoustic resonator 21b can have similar shapes but different aspect ratios ARa and ARb, the difference between the aspect ratio ARa of the first acoustic resonator 21a and the aspect ratio ARb of the second acoustic resonator 21b can produce a difference in anti-resonance frequency, but will not cause a difference in the resonant frequency between the first acoustic resonator 21a and the second acoustic resonator 21b.

[0174] Figure 4B It shows the basis Figure 4A A graph showing the change in the anti-resonance frequency of an acoustic resonator due to the change in its aspect ratio.

[0175] Reference Figure 4B The impedance Z of the acoustic resonator is maximum at the anti-resonance frequencies fa1 and fa2, and minimum at the resonant frequency fr. As the aspect ratio AR of the acoustic resonator increases, the anti-resonance frequency decreases from the first anti-resonance frequency fa1 to the second anti-resonance frequency fa2, and the resonant frequency fr can be basically fixed.

[0176] For example, the aspect ratios of the plurality of shunt acoustic resonators in the bulk acoustic resonator filter according to embodiments of the present disclosure may be different from each other, thereby reducing the anti-resonance frequency difference fa1-fa2 between the plurality of shunt acoustic resonators.

[0177] Figure 4C This illustrates the change in aspect ratio of the shunt acoustic resonator as it is connected to the closest or joint component, through... Figure 3H A graph showing the power variation of multiple shunt acoustic resonators.

[0178] Reference Figure 4C ,pass Figure 3H The frequency at which the power of the shunt acoustic resonator closest to the ground or connecting member is at its minimum corresponds to the anti-resonance frequency of the shunt acoustic resonator, and can increase as the aspect ratio of the shunt acoustic resonator closest to the ground or connecting member decreases. Figure 3H The aspect ratio difference ARdiff between multiple shunt acoustic resonators can increase as the aspect ratio of the shunt acoustic resonator closest to the ground or joint component decreases.

[0179] Figure 4D It shows the basis Figure 4C The power variation shown is achieved through multiple shunt acoustic resonators. Figure 3H A graph showing the power variation of multiple shunt acoustic resonators.

[0180] Reference Figure 4D ,pass Figure 3H The frequency of the signal with the lowest power in a plurality of shunt acoustic resonators corresponds to the total anti-resonant frequency of the plurality of shunt acoustic resonators. As the difference in anti-resonant frequencies among the plurality of shunt acoustic resonators decreases, the minimum power through the plurality of shunt acoustic resonators increases. The minimum power through the plurality of shunt acoustic resonators increases as the aspect ratio difference (AR diff) between the plurality of shunt acoustic resonators decreases.

[0181] For example, increasing the aspect ratio difference (AR diff) among the multiple shunt acoustic resonators can reduce the parasitic impedance difference among the multiple shunt acoustic resonators. Therefore, increasing the aspect ratio difference (AR diff) among the multiple shunt acoustic resonators can reduce the anti-resonant frequency difference among the multiple shunt acoustic resonators and reduce the minimum power passing through the multiple shunt acoustic resonators. Therefore, energy loss at frequencies adjacent to the anti-resonant frequencies of the multiple shunt acoustic resonators in the bandwidth of the bulk acoustic resonator filter according to embodiments of the present disclosure can be reduced.

[0182] Figure 4E It shows the basis Figure 4D The power variation shown is achieved through multiple shunt acoustic resonators. Figure 3H The curves showing the amplitude of the second harmonic in the signals of multiple shunt acoustic resonators, and Figure 4F It is shown that in having a ratio Figure 3H When the aspect ratio of the largest of the multiple shunt acoustic resonators decreases, the shunt acoustic resonators connected most closely together decrease in size. Figure 3H A graph showing the amplitude of the second harmonic in the signal of multiple shunt acoustic resonators.

[0183] Reference Figure 4E and Figure 4F This increases the aspect ratio difference (AR diff) between multiple shunt acoustic resonators, thereby offsetting the parasitic impedance differences between them and reducing the maximum amplitude of the second harmonic in the signal passing through the multiple shunt acoustic resonators. Therefore, the linearity and / or heat dissipation characteristics of the bulk acoustic resonator filter according to embodiments of this disclosure can be improved.

[0184] Figure 4G It is shown Figure 3H The bandwidth curve of the bulk acoustic resonator filter.

[0185] Reference Figure 4G According to embodiments of the present disclosure, the bandwidth BW of the bulk acoustic resonator filter is within a frequency range where the S-parameter is high between the first radio frequency (RF) port and the second radio frequency (RF) port.

[0186] Since the resonant frequencies fr (shunt) of multiple shunt acoustic resonators can be outside the bandwidth BW, and the anti-resonant frequencies fa (shunt) of multiple shunt acoustic resonators can be within the bandwidth BW, reducing the difference in the anti-resonant frequencies fa (shunt) of multiple shunt acoustic resonators is more important than reducing the difference in the resonant frequencies fr (shunt) of multiple shunt acoustic resonators in order to reduce energy loss.

[0187] Therefore, the difference in the anti-resonance frequency fa (shunt) among multiple shunt acoustic resonators can be smaller than the difference in the resonance frequency fr (shunt) among multiple shunt acoustic resonators, and the difference in the aspect ratio among multiple shunt acoustic resonators can effectively reduce the difference in the anti-resonance frequency fa (shunt) among multiple shunt acoustic resonators.

[0188] The resonant frequency fr (series) of at least one series acoustic resonator may be higher than the resonant frequency fr (shunt) of each of the plurality of shunt acoustic resonators, and the anti-resonant frequency fa (series) of at least one series acoustic resonator may be higher than the anti-resonant frequency fa (shunt) of each of the plurality of shunt acoustic resonators. The difference in resonant frequencies fr (shunt) among the plurality of shunt acoustic resonators may be less than the difference between the highest resonant frequency fr (shunt) among the plurality of shunt acoustic resonators and the resonant frequency fr (series) of at least one series acoustic resonator. For example, the difference in resonant frequencies fr (shunt) and / or the difference in anti-resonant frequencies fa (shunt) among the plurality of shunt acoustic resonators may be small.

[0189] Figure 5A This is a view illustrating aspect ratio measurements of various types of acoustic resonators according to embodiments of the present disclosure, and... Figure 5B This is a view illustrating asymmetrical and symmetrical structures of a bulk acoustic resonator resonator filter / package according to embodiments of the present disclosure.

[0190] Reference Figure 5A and Figure 5B Each of the multiple acoustic resonators R1, R2, R3, R4, R5, R6, R7, R8, R9, and R10 in their stacked regions can have a [missing information - likely a property or characteristic]. Figure 4A The pentagonal shape of each of the stacked regions of the first acoustic resonator 21a and the second acoustic resonator 21b is different from the quadrilateral shape. For example, the number of sides of each of the stacked regions of the multiple acoustic resonators R1, R2, R3, R4, R5, R6, R7, R8, R9 and R10 can be changed according to the design.

[0191] Reference Figure 5AThe longitudinal and transverse directions, which serve as references for determining the aspect ratios AR1, AR2, AR3, AR4, AR5, AR6, AR7, AR8, AR9, and AR10 of the multiple acoustic resonators R1, R2, R3, R4, R5, R6, R7, R8, AR9, and AR10, can be changed according to the shape (or rotation) of the multiple acoustic resonators R1, R2, R3, R4, R5, R6, R7, R8, R9, and R10. For example, although multiple acoustic resonators R1, R2, R3, R4, and R5 have different rotation angles relative to each other, the aspect ratios AR1, AR2, AR3, AR4, and AR5 of multiple acoustic resonators R1, R2, R3, R4, and R5 can be the same as each other, and although multiple acoustic resonators R6, R7, R8, R9, and R10 have different rotation angles relative to each other, the aspect ratios AR6, AR7, AR8, AR9, and AR10 of multiple acoustic resonators R6, R7, R8, R9, and R10 can be the same as each other.

[0192] For example, multiple acoustic resonators R1, R2, R3, R4, R5, R6, R7, R8, R9, and R10 may have different rotation angles and different symmetries (symmetries at the center of the acoustic resonators in the longitudinal and / or transverse directions). The symmetry of multiple acoustic resonators R6, R7, R8, R9, and R10 may be higher than the symmetry of multiple acoustic resonators R1, R2, R3, R4, and R5.

[0193] The characteristics of aspect ratio AR of multiple acoustic resonators R1, R2, R3, R4 and R5 with relatively low symmetry are shown in Table 1 below.

[0194] Table 1

[0195] AR fr[GHz] fa[GHz] <![CDATA[K t 2 [%]]]> IL[dB] Attn[dB] 1.3 3.5550 3.6915 8.80 -0.049 32.8 2.4 3.5550 3.6905 8.74 -0.034 31.4 3.8 3.5550 3.6880 8.59 -0.032 28.7

[0196] In this case, the lower the insertion loss IL, the better, and the higher the attenuation characteristic Attn, the better. As the aspect ratio AR of multiple acoustic resonators R1, R2, R3, R4, and R5 increases from 1.3 to 2.4, the insertion loss IL can be significantly reduced, and as the aspect ratio AR of multiple acoustic resonators R1, R2, R3, R4, and R5 decreases from 3.8 to 2.4, the attenuation characteristic Attn of multiple acoustic resonators R1, R2, R3, R4, and R5 can be significantly increased.

[0197] Therefore, among the multiple shunt acoustic resonators of the bulk acoustic resonator filter according to embodiments of this disclosure, the shunt acoustic resonator with a relatively high aspect ratio AR can have an aspect ratio AR greater than 1.3 and less than 3.8, or an aspect ratio AR of approximately 2.4 (e.g., 2.4 ± 0.2). Thus, the bulk acoustic resonator filter can have low insertion loss IL and high attenuation characteristics Attn.

[0198] The characteristics of the aspect ratio AR of multiple acoustic resonators R6, R7, R8, R9 and R10 with relatively high symmetry are shown in Table 2 below.

[0199] Table 2

[0200] AR <![CDATA[K t 2 [%]]]> IL[dB] Attn[dB] 4.8 8.59 -0.025 30.9 6.6 8.47 -0.022 29.6

[0201] As the aspect ratio AR increases, the width of the metal layer connected to the acoustic resonator can be increased. Therefore, the insertion loss IL can be reduced.

[0202] Multiple acoustic resonators R6, R7, R8, R9, and R10 with relatively high symmetry can have a relatively high aspect ratio AR of 4.8 to 6.6, and can have attenuation characteristics Attn similar to those Attn of multiple acoustic resonators R1, R2, R3, R4, and R5 with relatively low symmetry.

[0203] For example, multiple acoustic resonators R6, R7, R8, R9, and R10 with relatively high symmetry can have an aspect ratio AR greater than or equal to 4.8 and less than or equal to 6.6. Therefore, a bulk acoustic resonator filter can have low insertion loss IL and high attenuation characteristics Attn.

[0204] Acoustic resonators with relatively high symmetry and relatively high aspect ratio (AR) can be effectively used as series acoustic resonators where low insertion loss is relatively more important, and can also be used in shunt acoustic resonators with relatively high aspect ratio (AR) among multiple shunt acoustic resonators. In this case, acoustic resonators with relatively low symmetry and relatively low aspect ratio (AR) (greater than 1.3 and less than 3.8) can be effectively used in shunt acoustic resonators that are positioned closer to ground or the bonding member.

[0205] Since all acoustic resonators having the aspect ratios AR listed in Tables 1 and 2 have at least good insertion loss IL or at least good attenuation characteristics Attn, the aspect ratio AR of each of the plurality of shunt acoustic resonators of the bulk acoustic resonator filter according to embodiments of the present disclosure can fall within the range of greater than 1.3 and less than or equal to 6.6, and can be appropriately optimized within this range.

[0206] Reference Figure 5BThe centers CP1, CP2, CP3, CP4, CP5, CP6, CP7, CP8, CP9, and CP10 of the major axes MA1, MA2, MA3, MA4, MA5, MA6, MA7, MA8, MA9, and MA10 of the multiple acoustic resonators R1, R2, R3, R4, R5, R6, R7, R8, R9, and R10 can be used as references for measuring the symmetry of the multiple acoustic resonators R1, R2, R3, R4, R5, R6, R7, R8, R9, and R10.

[0207] For example, as the distance between the centers CP1, CP2, CP3, CP4, and CP5 of multiple acoustic resonators R1, R2, R3, R4, and R5 and their centroids increases, the multiple acoustic resonators R1, R2, R3, R4, and R5 can become more asymmetrical. For example, when multiple acoustic resonators R6, R7, R8, R9, and R10 are perfectly symmetrical, the centers CP6, CP7, CP8, CP9, and CP10 of multiple acoustic resonators R6, R7, R8, R9, and R10 can be located at the centroids of multiple acoustic resonators R6, R7, R8, R9, and R10. In this case, the long axes MA1, MA2, MA3, MA4, MA5, MA6, MA7, MA8, MA9 and MA10 can have the longest distance among the distances between the vertices of multiple acoustic resonators R1, R2, R3, R4, R5, R6, R7, R8, R9 and R10.

[0208] Figure 5C This is a view showing that the aspect ratio can be changed according to the connection length between multiple shunt acoustic resonators of a bulk acoustic resonator filter / package according to an embodiment of the present disclosure.

[0209] Reference Figure 5C When the connection length CL1 between the multiple shunt acoustic resonators 21a and 21b is long, the aspect ratio difference (AR difference) between the multiple shunt acoustic resonators 21a and 21b can be large. When the connection length CL2 between the multiple shunt acoustic resonators 21a and 21b is short, the aspect ratio difference (AR difference) between the multiple shunt acoustic resonators 21a and 21b can be small. The connection lengths CL1 and CL2 can be the lengths of the portions of metal layers 1180 and 1190 located between the multiple shunt acoustic resonators 21a and 21b.

[0210] Therefore, the parasitic impedance differences between the multiple shunt acoustic resonators 21a and 21b can be offset. According to the design, metal layers 1180 and 1190 are interchangeable, and the aspect ratio difference (AR difference) can be changed accordingly.

[0211] Figure 6AThis is a plan view illustrating a specific structure of an acoustic resonator that may be included in a bulk acoustic resonator filter / package according to an embodiment of the present disclosure. Figure 6B It is along Figure 6A A cross-sectional view taken from line VIB-VIB' in the diagram. Figure 6C It is along Figure 6A The cross-sectional view taken by line VIC-VIC' in the diagram, and Figure 6D It is along Figure 6A The cross-sectional view taken from line VID-VID' in the diagram.

[0212] Reference Figures 6A to 6D The acoustic resonator 100a may include a substrate 1110, an insulating layer 1115, a resonant part 1120, and a hydrophobic layer 1130.

[0213] Substrate 1110 may be a silicon substrate. In the example, a silicon wafer or a silicon-on-insulator (SOI) substrate may be used as substrate 1110.

[0214] An insulating layer 1115 may be disposed on the upper surface of the substrate 1110 to electrically isolate the substrate 1110 from the resonant portion 1120. In addition, when the cavity C is formed during the fabrication of the acoustic resonator 100a, the insulating layer 1115 can prevent the substrate 1110 from being etched by etching gas.

[0215] In this case, the insulating layer 1115 can be formed using at least one of silicon dioxide (SiO2), silicon nitride (Si3N4), aluminum oxide (Al2O3), and aluminum nitride (AlN), and can be formed by at least one of processes such as chemical vapor deposition, radio frequency (RF) magnetron sputtering, and evaporation.

[0216] The support layer 1140 may be formed on the insulating layer 1115 and may be disposed around the cavity C and the etch stop portion 1145.

[0217] Cavity C can be formed as an empty space, and can be formed by removing a portion of the sacrificial layer formed during the preparation of support layer 1140, and the remaining portion of the sacrificial layer can be formed as support layer 1140.

[0218] The support layer 1140 may be formed using a material that can be easily etched (such as polysilicon, polymer or other suitable material). However, the material of the support layer 1140 is not limited to this.

[0219] The etching stop portion 1145 may be provided along the boundary of the cavity C. The etching stop portion 1145 may be provided to prevent etching beyond the cavity area during the formation of the cavity C.

[0220] The film layer 1150 can be formed on the support layer 1140 and can define the upper surface of the cavity C. Therefore, the film layer 1150 can be formed using a material that is not easily removed during the formation of the cavity C.

[0221] In the example, when an etching gas containing fluorine (F) or chlorine (Cl) halides is used to remove a portion (e.g., a cavity region) of the support layer 1140, the film layer 1150 may be formed using a material with low reactivity to the etching gas. In this case, the film layer 1150 may include at least one of silicon dioxide (SiO2), silicon nitride (Si3N4), etc.

[0222] Furthermore, the film layer 1150 may include a dielectric layer comprising at least one material selected from magnesium oxide (MgO), zirconium dioxide (ZrO2), aluminum nitride (AlN), lead zirconate titanate (PZT), gallium arsenide (GaAs), hafnium dioxide (HfO2), aluminum oxide (Al2O3), titanium dioxide (TiO2), and zinc oxide (ZnO), or may include a metal layer comprising at least one material selected from aluminum (Al), nickel (Ni), chromium (Cr), platinum (Pt), gallium (Ga), and hafnium (Hf). However, the construction of this disclosure is not limited thereto.

[0223] The resonant section 1120 may include a first electrode 1121, a piezoelectric layer 1123, and a second electrode 1125. In the resonant section 1120, the first electrode 1121, the piezoelectric layer 1123, and the second electrode 1125 may be stacked sequentially starting from the first electrode 1121. Therefore, in the resonant section 1120, the piezoelectric layer 1123 may be disposed between the first electrode 1121 and the second electrode 1125.

[0224] The resonant portion 1120 may be formed on the film layer 1150, such that the film layer 1150, the first electrode 1121, the piezoelectric layer 1123, and the second electrode 1125 are stacked sequentially, and the film layer 1150 may also be a part of the resonant portion 1120. The resonant portion 1120 may have an aspect ratio that is the aspect ratio of the stacked region where the first electrode 1121, the piezoelectric layer 1123, and the second electrode 1125 are stacked.

[0225] The piezoelectric layer 1123 of the resonant section 1120 can resonate according to the signal applied to the first electrode 1121 and the second electrode 1125 to generate a resonant frequency and an anti-resonant frequency.

[0226] The resonant portion 1120 can be divided into a central portion S and an extension portion E. In the central portion S, the first electrode 1121, the piezoelectric layer 1123, and the second electrode 1125 are stacked in a substantially flat manner. In the extension portion E, the insertion layer 1170 is located between the first electrode 1121 and the piezoelectric layer 1123.

[0227] The central portion S is a region located at the center of the resonant portion 1120, and the extension portion E is a region located along the outer periphery of the central portion S of the resonant portion 1120. Therefore, the extension portion E is a region extending outward from the central portion S and is formed in a continuous annular shape along the outer periphery of the central portion S. If necessary, the extension portion E can be formed in a discontinuous annular shape in which some of these regions are removed.

[0228] Therefore, as Figure 6B As shown, in the cross-section of the resonant portion 1120 cut through the central portion S, the extension portion E can be disposed on the opposite side of the central portion S. Additionally, the insertion layer 1170 can be disposed on the extension portion E.

[0229] The insertion layer 1170 may have a sloping surface L, the thickness of which increases in the direction away from the central portion S. The thickness of the sloping surface L is the thickness of the sloping portion of the insertion layer 1170 including the sloping surface L, and the angle or sloping angle of the sloping surface L is the angle of the sloping surface L relative to the flat upper surface of the first electrode 1121.

[0230] In the extension E, the piezoelectric layer 1123 and the second electrode 1125 may be disposed on the insertion layer 1170. Therefore, the piezoelectric layer 1123 and the second electrode 1125 disposed in the extension E may have inclined surfaces conforming to the shape of the insertion layer 1170.

[0231] The extension portion E can be defined as being included in the resonant portion 1120, such that resonance can also occur in the extension portion E. However, this disclosure is not limited thereto. Depending on the structure of the extension portion E, resonance may not occur in the extension portion E, but may occur only in the central portion S.

[0232] The first electrode 1121 and the second electrode 1125 may be formed using a conductive material (e.g., gold, molybdenum, ruthenium, iridium, aluminum, platinum, titanium, tungsten, palladium, tantalum, chromium, nickel, or an alloy including at least one thereof). However, this disclosure is not limited thereto.

[0233] In the resonant section 1120, the first electrode 1121 may be formed with an area larger than that of the second electrode 1125, and the first metal layer 1180 may be formed along the outer periphery of the first electrode 1121 on at least a portion of the first electrode 1121. Therefore, the first metal layer 1180 may be configured to be spaced apart from the second electrode 1125 by a predetermined distance and surround the resonant section 1120.

[0234] Since the first electrode 1121 is disposed on the film layer 1150, the first electrode 1121 can be formed to be completely flat. Since the second electrode 1125 can be disposed on the piezoelectric layer 1123, the second electrode 1125 can be bent to correspond to the shape of the piezoelectric layer 1123.

[0235] The first electrode 1121 can be implemented as either an input electrode for inputting an electrical signal such as a radio frequency (RF) signal or an output electrode for outputting an electrical signal such as a radio frequency (RF) signal.

[0236] The second electrode 1125 may be entirely disposed in the central portion S, or partially disposed in the extended portion E. The second electrode 1125 may be divided into a portion disposed on the piezoelectric portion 1123a of the piezoelectric layer 1123 and a portion disposed on the bent portion 1123b of the piezoelectric layer 1123.

[0237] Specifically, the second electrode 1125 can be configured to completely cover the piezoelectric portion 1123a and partially cover the inclined portion 11231 of the piezoelectric layer 1123. Therefore, the portion of the second electrode 1125 disposed in the extension E (1125a, ...) Figure 6D The area of ​​the second electrode 1125 disposed in the resonant portion 1120 can be formed to have an area smaller than that of the inclined surface of the inclined portion 11231, and the portion of the second electrode 1125 disposed in the resonant portion 1120 can be formed to have an area smaller than that of the piezoelectric layer 1123.

[0238] Therefore, as Figure 6B As shown, in a vertical cross-section through the central portion S, the resonant portion 1120 can have an end portion of the second electrode 1125 disposed in the extension portion E. Furthermore, at least a portion of the end portion of the second electrode 1125 disposed in the extension portion E can be configured to overlap with the insertion layer 1170. The term "overlap" means that when the second electrode 1125 is projected onto a plane on which the insertion layer 1170 is disposed, the shape of the second electrode 1125 projected onto that plane overlaps with the insertion layer 1170.

[0239] The second electrode 1125 can be used as either an input electrode for inputting an electrical signal such as a radio frequency (RF) signal or an output electrode for outputting an electrical signal such as a radio frequency (RF) signal. For example, when the first electrode 1121 is used as an input electrode, the second electrode 1125 can be used as an output electrode. Alternatively, when the first electrode 1121 is used as an output electrode, the second electrode 1125 can be used as an input electrode.

[0240] like Figure 6D As shown, when the end of the second electrode 1125 is disposed on the inclined portion 11231 (described later) of the piezoelectric layer 1123, the acoustic impedance of the local structure of the resonant portion 1120 can be formed from the central portion S in a sparse / dense / sparse / dense manner to increase the reflection interface of the transverse waves reflected towards the interior of the resonant portion 1120. Therefore, most of the transverse waves can not flow out of the resonant portion 1120, but can be reflected to flow towards the interior of the resonant portion 1120, thereby improving the performance of the acoustic resonator 100a.

[0241] The piezoelectric layer 1123 may be a portion that converts electrical energy into mechanical energy in the form of elastic waves through the piezoelectric effect, and may be formed on the first electrode 1121 and the insertion layer 1170 (described later).

[0242] Zinc oxide (ZnO), aluminum nitride (AlN), doped aluminum nitride, lead zirconate titanate, quartz, or other piezoelectric materials may be selectively used as the material for the piezoelectric layer 1123. In the case of doped aluminum nitride, rare earth metals, transition metals, or alkaline earth metals may be further included. Rare earth metals may include at least one of scandium (Sc), erbium (Er), yttrium (Y), and lanthanum (La). Transition metals may include at least one of hafnium (Hf), titanium (Ti), zirconium (Zr), tantalum (Ta), and niobium (Nb). Furthermore, alkaline earth metals may include magnesium (Mg). The amount of elements doped into aluminum nitride (AlN) may range from 0.1 at% to 30 at% based on the total content of doped aluminum nitride (AlN), but is not limited thereto.

[0243] The piezoelectric layer 1123 can be formed using a material obtained by doping aluminum nitride (AlN) with scandium (Sc). In this case, the piezoelectric constant can be increased to increase the K of the acoustic resonator 100a. t 2 .

[0244] The piezoelectric layer 1123 may include a piezoelectric portion 1123a disposed in the central portion S and a curved portion 1123b disposed in the extension portion E.

[0245] The piezoelectric portion 1123a may be a portion directly stacked on the upper surface of the first electrode 1121. Therefore, the piezoelectric portion 1123a may be located between the first electrode 1121 and the second electrode 1125, and formed flat together with the first electrode 1121 and the second electrode 1125.

[0246] The curved portion 1123b can be defined as a region extending outward from the piezoelectric portion 1123a, and is disposed in the extended portion E.

[0247] The bent portion 1123b may be disposed on the insertion layer 1170 (described later) and may be shaped such that its upper surface rises with the shape of the insertion layer 1170. Thus, the piezoelectric layer 1123 may be bent or folded at the boundary between the piezoelectric portion 1123a and the bent portion 1123b, and the bent portion 1123b may rise to correspond to the thickness and shape of the insertion layer 1170.

[0248] The curved portion 1123b can be divided into an inclined portion 11231 and an extended portion 11232.

[0249] The inclined portion 11231 may be a portion formed to be inclined along the inclined surface L of the insertion layer 1170 (described later). The extension portion 11232 may be a portion extending outward from the inclined portion 11231.

[0250] The inclined portion 11231 may be formed as an inclined surface L parallel to the insertion layer 1170, and the inclined angle of the inclined portion 11231 may be the same as the inclined angle θ of the inclined surface L of the insertion layer 1170 (see [reference]). Figure 6D (The amplified portion in the middle).

[0251] The insertion layer 1170 may be disposed along the surface formed by the film layer 1150, the first electrode 1121 and the etch stop portion 1145. Therefore, the insertion layer 1170 may be partially disposed in the resonant portion 1120 and may be disposed between the first electrode 1121 and the piezoelectric layer 1123.

[0252] The insertion layer 1170 may be disposed around the central portion S to support the curved portion 1123b of the piezoelectric layer 1123. Therefore, the curved portion 1123b of the piezoelectric layer 1123 may be divided into an inclined portion 11231 and an extended portion 11232 disposed along the shape of the insertion layer 1170.

[0253] In the example, the insertion layer 1170 may be disposed in the area other than the central portion S. For example, the insertion layer 1170 may be disposed in all areas of the substrate 1110 except for the central portion S, or it may be disposed in some areas of the substrate 1110 except for the central portion S.

[0254] A portion of the insert layer 1170 may be formed to have a thickness that increases in the direction extending away from the central portion S. Therefore, the insert layer 1170 may be formed to have a side surface disposed adjacent to the central portion S, and this side surface may be formed as an inclined surface L with a predetermined tilt angle θ. In the example, the predetermined tilt angle θ may be greater than or equal to 5 degrees and less than or equal to 70 degrees, but is not limited thereto.

[0255] The inclined portion 11231 of the piezoelectric layer 1123 can be formed along the inclined surface L of the insertion layer 1170, and therefore can be formed at the same inclined angle as the inclined surface L of the insertion layer 1170. Therefore, like the inclined surface L of the insertion layer 1170, the inclined angle of the inclined portion 11231 can also be formed to be greater than or equal to 5 degrees and less than or equal to 70 degrees, but is not limited thereto. This configuration can also be applied to the portion of the second electrode 1125 stacked on the inclined surface L of the insertion layer 1170.

[0256] The insertion layer 1170 may be formed using dielectric materials such as silicon dioxide (SiO2), aluminum nitride (AlN), aluminum oxide (Al2O3), silicon nitride (Si3N4), magnesium oxide (MgO), zirconium dioxide (ZrO2), lead zirconate titanate (PZT), gallium arsenide (GaAs), hafnium dioxide (HfO2), titanium dioxide (TiO2), zinc oxide (ZnO) or other suitable dielectric materials, but may be formed using materials different from those used in the piezoelectric layer 1123.

[0257] Alternatively, the insertion layer 1170 may be formed using a metallic material. When the acoustic resonator 100a is used for 5G communication, the resonant portion 1120 may generate a large amount of heat, therefore the heat generated by the resonant portion 1120 should be dissipated evenly. The insertion layer 1170 may be formed using an aluminum alloy material containing scandium (Sc).

[0258] The resonant part 1120 can be configured to be spaced apart from the substrate 1110 by a cavity C formed as an empty space.

[0259] In the manufacturing process of the acoustic resonator 100a, it is possible to introduce the inlet hole ( Figure 6A H) supplies etching gas (or etching solution) to remove a portion of the support layer 1140 to form cavity C.

[0260] Therefore, cavity C can be a space having an upper surface (top surface) and side surfaces (wall surfaces) defined by film layer 1150 and a bottom surface defined by substrate 1110 or insulating layer 1115. Film layer 1150 may be formed only on the upper surface (top surface) of cavity C according to the manufacturing process sequence.

[0261] The protective layer 1160 may be disposed along the surface of the acoustic resonator 100a to protect the acoustic resonator 100a from the influence of the external environment. The protective layer 1160 may be disposed along the surface defined by the curved portion 1123b of the second electrode 1125 and the piezoelectric layer 1123.

[0262] In the final process of the manufacturing method, the protective layer 1160 may be partially removed for frequency control. For example, the thickness of the protective layer 1160 may be adjusted by frequency fine-tuning during the manufacturing process.

[0263] The protective layer 1160 may include any one of silicon dioxide (SiO2), silicon nitride (Si3N4), magnesium oxide (MgO), zirconium dioxide (ZrO2), aluminum nitride (AlN), lead zirconate titanate (PZT), gallium arsenide (GaAs), hafnium dioxide (HfO2), aluminum oxide (Al2O3), titanium dioxide (TiO2), zinc oxide (ZnO), amorphous silicon (a-Si), and polycrystalline silicon (p-Si), but this disclosure is not limited thereto.

[0264] The first electrode 1121 and the second electrode 1125 can extend outward from the resonant portion 1120. In addition, the first metal layer 1180 and the second metal layer 1190 can each be disposed on the upper surface of the extension portion of the resonant portion 1120.

[0265] The first metal layer 1180 and the second metal layer 1190 can be formed using any of the following materials: gold (Au), gold-tin (Au-Sn) alloy, copper (Cu), copper-tin (Cu-Sn) alloy, aluminum (Al), and aluminum alloys. The aluminum alloy can be an aluminum-germanium (Al-Ge) alloy or an aluminum-scandium (Al-Sc) alloy.

[0266] The first metal layer 1180 and the second metal layer 1190 can be used as connection wiring to electrically connect the electrodes of the acoustic resonator 100a (e.g., the first electrode 1121 and the second electrode 1125) to the electrodes of adjacent acoustic resonators on the substrate 1110.

[0267] At least a portion of the first metal layer 1180 may contact the protective layer 1160 and may be bonded to the first electrode 1121.

[0268] In the resonant section 1120, the first electrode 1121 may be formed to have an area larger than that of the second electrode 1125, and the first metal layer 1180 may be formed on the outer peripheral portion of the first electrode 1121.

[0269] Therefore, the first metal layer 1180 may be disposed along the outer periphery of the resonant portion 1120 and may be configured to surround the second electrode 1125. However, this disclosure is not limited thereto.

[0270] In the acoustic resonator 100a, a hydrophobic layer 1130 may be disposed on the surface of the protective layer 1160 and the inner wall of the cavity C. The hydrophobic layer 1130 can suppress the adsorption of water and hydroxyl (OH groups) to significantly reduce frequency variations, thereby maintaining uniform resonator performance.

[0271] The hydrophobic layer 1130 can be formed using a self-assembled monolayer (SAM) material instead of a polymer. When the hydrophobic layer 1130 is formed using a polymer, the quality of the polymer affects the resonant section 1120. Since the hydrophobic layer 1130 can be formed using a self-assembled monolayer in the acoustic resonator 100a, the variation in the resonant frequency of the acoustic resonator 100a can be significantly reduced. Furthermore, the thickness of the hydrophobic layer 1130 in the cavity C can be uniform.

[0272] The hydrophobic layer 1130 can be formed by vapor deposition of a precursor that may have hydrophobic properties. In this case, the hydrophobic layer 1130 can be deposited as a monolayer with a thickness of 100 angstroms or less (in the example, a few angstroms to tens of angstroms). The precursor that may have hydrophobic properties can be formed using a material that has a static contact angle with water of 90 degrees or greater after deposition. In the example, the hydrophobic layer 1130 may contain a fluorine (F) component and may include both fluorine (F) and silicon (Si). In particular, fluorocarbons with silicon heads can be used, but this disclosure is not limited thereto.

[0273] To improve the adhesion between the self-assembled monolayer forming the hydrophobic layer 1130 and the protective layer 1160, an adhesion layer (not shown) may be formed on the protective layer 1160 before the hydrophobic layer 1130 is formed.

[0274] An adhesion layer can be formed by vapor-depositing a precursor with hydrophobic functional groups on the surface of the protective layer 1160.

[0275] The precursor used for depositing the adhesion layer can be a hydrocarbon with a silicon head or a siloxane with a silicon head, but is not limited to these.

[0276] The hydrophobic layer 1130 can be formed after the formation of the first metal layer 1180 and the second metal layer 1190, and therefore can be formed along the surfaces of the protective layer 1160, the first metal layer 1180 and the second metal layer 1190.

[0277] Figures 6B to 6D An example is shown where the hydrophobic layer 1130 is not disposed on the surfaces of the first metal layer 1180 and the second metal layer 1190, but this disclosure is not limited thereto. The hydrophobic layer 1130 may also be disposed on the surfaces of the first metal layer 1180 and the second metal layer 1190 if desired.

[0278] Furthermore, the hydrophobic layer 1130 can be disposed not only on the upper surface of the protective layer 1160, but also on the inner surface of the cavity C.

[0279] When the hydrophobic layer 1130 is formed in cavity C, the hydrophobic layer 1130 can be formed on the entire inner wall of cavity C. Therefore, the hydrophobic layer 1130 can also be formed on the lower surface of the film layer 1150 that forms the lower surface of the resonant part 1120. In this case, the adsorption of hydroxyl groups on the lower part of the resonant part 1120 can be suppressed.

[0280] The adsorption of hydroxyl groups occurs not only in the protective layer 1160 but also in the cavity C. Therefore, in order to significantly reduce the mass load caused by the adsorption of hydroxyl groups and the resulting decrease in the resonant frequency of the acoustic resonator 100a, the adsorption of hydroxyl groups can be blocked by a hydrophobic layer 1130 in the protective layer 1160 and on the upper surface of the cavity C (the lower surface of the film layer 1150) (e.g., the lower surface of the resonator).

[0281] In addition, when the hydrophobic layer 1130 is formed on the upper surface, lower surface and side surface of the cavity C, it can provide the effect of suppressing the occurrence of static friction, which is the phenomenon that the resonant part 1120 adheres to the insulating layer 1115 due to surface tension during the wetting process or cleaning process after the cavity C is formed.

[0282] An example has been described in which the hydrophobic layer 1130 is formed on the entire inner wall of the cavity C, but this disclosure is not limited thereto. Alternatively, various modifications may be made, for example, the hydrophobic layer 1130 may be formed only on the upper surface of the cavity C, or the hydrophobic layer 1130 may be formed only on at least a portion of the lower surface and side surfaces of the cavity C.

[0283] Compared to the aspect ratio ratio of the plurality of shunt acoustic resonators in the bulk acoustic resonator filter / package according to embodiments of the present disclosure, the ratio of the thicknesses T of the plurality of shunt acoustic resonators in the Z direction can be closer to 1. In this case, the thickness T can be defined as the thickness from the upper surface of the film layer 1150 to the upper surface of the hydrophobic layer 1130, and can affect the resonant frequency and / or anti-resonant frequency of the acoustic resonator. When the resonant frequencies and / or anti-resonant frequencies of the plurality of shunt acoustic resonators are substantially equal to each other, the thicknesses T of the plurality of shunt acoustic resonators can be substantially equal to each other, and the ratio of the thicknesses T of the plurality of shunt acoustic resonators can be 1. For example, the thickness T can be measured by analysis using at least one of transmission electron microscopy (TEM), atomic force microscopy (AFM), scanning electron microscopy (SEM), optical microscopy, and surface profilometry.

[0284] Figure 6E and Figure 6F This is a cross-sectional view showing the structure of the internal and external spaces of an electrical connector acoustic resonator filter / package according to an embodiment of the present disclosure.

[0285] Reference Figure 6E and Figure 6F The bulk acoustic wave resonator packages 100f and 100g according to embodiments of the present disclosure may further include at least one of a bump 1310, a connection pattern 11320, and a second hydrophobic layer 1330.

[0286] A hydrophobic layer 1130 may be disposed between the resonant portion 1120 and the cover 1210, and may be more hydrophobic than the cover 1210. Therefore, the resonant portion 1120 can reduce the adsorption of organic matter, moisture, or other foreign matter that may be generated during the process of forming the joining member 1220, thereby further improving the characteristics of the resonant portion 1120. In this example, the hydrophobic layer may be formed on the upper surface of the resonant portion 1120.

[0287] Reference Figure 6EAt least a portion of the connecting pattern 11320 can pass through the substrate 1110, can be electrically connected to at least one of the first electrode 1121 and the second electrode 1125, and can contact the second hydrophobic layer 1330. Therefore, the resonant portion 1120 can be electrically connected to an external device outside the bulk acoustic wave resonator package 100f.

[0288] The second hydrophobic layer 1330 may be disposed on the surface of the substrate 1110 opposite to the surface of the substrate 1110 facing the cover 1210 (e.g., the upper surface) and may be more hydrophobic than the substrate 1110. Therefore, the adsorption of organic matter, moisture or other foreign matter that may be generated in the process of forming the bonding member 1220 by the connection pattern 11320 can be reduced, thereby further reducing the transmission loss in the connection pattern 11320.

[0289] Reference Figure 6F At least a portion of the connecting pattern 11320 can pass through the cover 1210, can be electrically connected to at least one of the first electrode 1121 and the second electrode 1125, and can contact the second hydrophobic layer 1330. Therefore, the resonant portion 1120 can be electrically connected to an external device outside the bulk acoustic resonator package 100g.

[0290] The second hydrophobic layer 1330 may be disposed on the surface of the cover 1210 opposite to the surface of the cover 1210 facing the substrate 1110 (e.g., the lower surface) and may be more hydrophobic than the cover 1210. Therefore, the adsorption of organic matter, moisture or other foreign matter that may be generated in the process of forming the bonding member 1220 by the connection pattern 11320 can be reduced, thereby further reducing the transmission loss in the connection pattern 11320.

[0291] In the example, with holes present in a portion of the substrate 1110 and / or cover 1210, the connection pattern 11320 can be formed by a process of depositing, coating or filling conductive metal (e.g., gold, copper, titanium-copper (Ti-Cu) alloy or other suitable material) on the sidewalls of the holes.

[0292] The process of forming holes in a portion of the substrate 1110 and / or the cover 1210 can be omitted. In the example, the resonant portion 1120 can receive electrical signals via lead bonding.

[0293] The bump 1310 may have a structure that supports the bulk acoustic wave resonator packages 100f and 100g, such that the bulk acoustic wave resonator packages 100f and 100g can be mounted on an external printed circuit board (PCB) on one side thereon. In the example, a portion of the connection pattern 11320 may have a pad shape that contacts the bump 1310.

[0294] The bulk acoustic wave resonator filter and bulk acoustic wave resonator package according to embodiments of the present disclosure can effectively improve performance (e.g., loss characteristics, frequency limiting characteristics, maximum power characteristics, heat generation characteristics, linearity characteristics, attenuation characteristics, or other characteristics).

[0295] While this disclosure includes specific examples, it will be readily understood upon understanding the content of this application that various changes in form and detail may be made to these examples without departing from the spirit and scope of the claims and their equivalents; for example, technical features in different embodiments may be combined with each other. Therefore, the scope of this disclosure is not limited by the specific embodiments but by the claims and their equivalents, and all variations within the scope of the claims and their equivalents shall be construed as being included in this disclosure.

Claims

1. A bulk acoustic resonator filter, comprising: The series section includes at least one series acoustic resonator that is connected in series between the first radio frequency port and the second radio frequency port. as well as Multiple shunt acoustic resonators are electrically connected in series between the first node of the series section and the first ground port. Each of the plurality of shunt acoustic resonators includes: a resonant section comprising a first electrode, a piezoelectric layer, and a second electrode stacked in a first direction. In each of the plurality of shunt acoustic resonators, the first electrode, the piezoelectric layer, and the second electrode of the resonant section are stacked on top of each other in the stacked region. The aspect ratio of the stacked region of each of the plurality of shunt acoustic resonators is equal to the ratio between the longest length of the stacked region along the extension direction of the longest side of the stacked region and the longest length of the stacked region in the direction perpendicular to the extension direction. The aspect ratios of the multiple shunt acoustic resonators include different aspect ratios. Among the plurality of shunt acoustic resonators, the aspect ratio of the shunt acoustic resonator closest to the first grounding port is smaller than the aspect ratio of the shunt acoustic resonator farther from the first grounding port.

2. The bulk acoustic resonator filter according to claim 1, wherein, The differences in aspect ratios between the multiple shunt acoustic resonators reduce the differences in anti-resonance frequencies between the multiple shunt acoustic resonators.

3. The bulk acoustic resonator filter according to claim 1, wherein, The difference in anti-resonance frequency among the plurality of shunt acoustic resonators is less than the difference in resonance frequency among the plurality of shunt acoustic resonators.

4. The bulk acoustic resonator filter according to claim 1, wherein, The plurality of shunt acoustic resonators are connected to each other through corresponding first electrodes or corresponding second electrodes, and The aspect ratio difference among the plurality of shunt acoustic resonators increases as the connection length between the plurality of shunt acoustic resonators increases.

5. The bulk acoustic resonator filter according to claim 1, wherein, The aspect ratio of the shunt acoustic resonator that is further away from the first grounding port electrical connection is in the range of 2.2 to 2.

6.

6. The bulk acoustic resonator filter according to claim 1, wherein, Each of the plurality of shunt acoustic resonators has an aspect ratio greater than 1.3 and less than or equal to 6.

6.

7. The bulk acoustic resonator filter according to claim 6, wherein, Each of the plurality of shunt acoustic resonators has an aspect ratio greater than 1.3 and less than 3.

8.

8. The bulk acoustic resonator filter according to claim 1, wherein, Each of the at least one series acoustic resonator includes: a resonant portion comprising a first electrode, a piezoelectric layer, and a second electrode stacked in the first direction, wherein the first electrode, piezoelectric layer, and second electrode of the resonant portion of each of the at least one series acoustic resonator are stacked on top of each other in a stacked region. The aspect ratio of the stacked region of each of the at least one series acoustic resonator is equal to the ratio between the longest length of the stacked region along the extension direction of the longest side of the stacked region and the longest length of the stacked region in the direction perpendicular to the extension direction. The symmetry of the shape of the stacked region of at least one of the plurality of shunt acoustic resonators is higher than the symmetry of the shape of the stacked region of at least one of the at least one series acoustic resonators.

9. The bulk acoustic resonator filter according to claim 8, wherein, The aspect ratio of at least one of the plurality of shunt acoustic resonators is greater than or equal to 4.8 and less than or equal to 6.

6.

10. The bulk acoustic resonator filter according to claim 1, wherein, The symmetry of the shape of the stacked regions of the multiple shunt acoustic resonators includes different symmetries, and The aspect ratio of the shunt acoustic resonator with higher symmetry among the plurality of shunt acoustic resonators is higher than that of the shunt acoustic resonator with lower symmetry among the plurality of shunt acoustic resonators.

11. The bulk acoustic resonator filter according to claim 10, wherein, The aspect ratio of the highly symmetrical shunt acoustic resonator is greater than or equal to 4.8 and less than or equal to 6.6, and The aspect ratio of the shunt acoustic resonator with low symmetry is greater than 1.3 and less than 3.

8.

12. The bulk acoustic resonator filter according to claim 1, wherein, The plurality of shunt acoustic resonators include a first shunt acoustic resonator, a second shunt acoustic resonator, and a third shunt acoustic resonator that are electrically connected in series with each other. The first shunt acoustic resonator and the second shunt acoustic resonator are connected to each other via a corresponding first electrode or a corresponding second electrode. The second shunt acoustic resonator and the third shunt acoustic resonator are connected to each other via a corresponding first electrode or a corresponding second electrode, and The aspect ratio difference between the first shunt acoustic resonator and the second shunt acoustic resonator is different from the aspect ratio difference between the second shunt acoustic resonator and the third shunt acoustic resonator.

13. The bulk acoustic resonator filter according to claim 1, wherein, The plurality of shunt acoustic resonators include a first shunt acoustic resonator and a second shunt acoustic resonator that are connected in series with each other between the first node of the series section and the first grounding port. The plurality of shunt acoustic resonators also include a third shunt acoustic resonator and a fourth shunt acoustic resonator that are connected in series with each other between the first node of the series section and the first grounding port. Each of the third and fourth shunt acoustic resonators includes: a resonant section comprising a first electrode, a piezoelectric layer, and a second electrode stacked in the first direction; the first electrode, piezoelectric layer, and second electrode of the resonant section of each of the third and fourth shunt acoustic resonators are stacked on top of each other in a stacked region. The aspect ratio of the stacked region of each of the third and fourth shunt acoustic resonators is equal to the ratio between the longest length of the stacked region along the extension direction of its longest side and the longest length of the stacked region in a direction perpendicular to the extension direction. The first and second shunt acoustic resonators, which are connected in series with each other, are connected in parallel with the third and fourth shunt acoustic resonators, which are also connected in series with each other.

14. The bulk acoustic resonator filter according to claim 13, wherein, One of the first and third shunt acoustic resonators is electrically connected to the first ground port through the first electrode of the first shunt acoustic resonator, and the other of the first and third shunt acoustic resonators is electrically connected to the first ground port through the second electrode of the other shunt acoustic resonator.

15. The bulk acoustic resonator filter according to claim 14, wherein, The aspect ratios of the third and fourth shunt acoustic resonators are different from each other, and The aspect ratio difference between the first shunt acoustic resonator and the second shunt acoustic resonator is different from the aspect ratio difference between the third shunt acoustic resonator and the fourth shunt acoustic resonator.

16. The bulk acoustic resonator filter according to claim 13, further comprising a fifth shunt acoustic resonator and a sixth shunt acoustic resonator connected in series between the second node of the series section and the second ground port. Each of the fifth shunt acoustic resonator and the sixth shunt acoustic resonator includes: The resonant section includes a first electrode, a piezoelectric layer, and a second electrode stacked in the first direction. The first electrode, piezoelectric layer, and second electrode of the resonant section of each of the fifth and sixth shunt acoustic resonators are stacked on top of each other in a stacked region. The aspect ratio of the stacked region of each of the fifth and sixth shunt acoustic resonators is equal to the ratio between the longest length of the stacked region along the extension direction of the longest side of the stacked region and the longest length of the stacked region in a direction perpendicular to the extension direction. The at least one series acoustic resonator includes a series acoustic resonator electrically connected between the first node and the second node. Compared to the second and fourth shunt acoustic resonators, the first and third shunt acoustic resonators are electrically connected closer to the first ground port. Compared to the sixth shunt acoustic resonator, the fifth shunt acoustic resonator is electrically connected closer to the second ground port. The size of the stacked region of each of the first and third shunt acoustic resonators is different from the size of the stacked region of the fifth shunt acoustic resonator, and The size of the stacked region of each of the second and fourth shunt acoustic resonators is different from the size of the stacked region of the sixth shunt acoustic resonator.

17. A bulk acoustic resonator filter, comprising: The series section includes at least one series acoustic resonator that is connected in series between the first radio frequency port and the second radio frequency port. as well as The shunt section includes multiple shunt acoustic resonators electrically connected between the series section and ground. Each of the plurality of shunt acoustic resonators includes: a resonant section comprising a first electrode, a piezoelectric layer, and a second electrode stacked in a first direction. In each of the plurality of shunt acoustic resonators, the first electrode, the piezoelectric layer, and the second electrode of the resonant section are stacked on top of each other in the stacked region. The aspect ratio of the stacked region of each of the plurality of shunt acoustic resonators is equal to the ratio between the longest length of the stacked region along the extension direction of the longest side of the stacked region and the longest length of the stacked region in a direction perpendicular to the extension direction. The first portion of the plurality of shunt acoustic resonators is electrically connected to ground via a first electrode, and the second portion of the plurality of shunt acoustic resonators is electrically connected to ground via a second electrode. The first portion and the second portion are electrically connected between the first node of the series connection and the ground port. The aspect ratio of the first portion of the plurality of shunt acoustic resonators electrically connected to ground via the first electrode is less than the aspect ratio of the second portion of the plurality of shunt acoustic resonators electrically connected to ground via the second electrode, and the first portion is closer to the grounding port than the second portion.

18. The bulk acoustic resonator filter according to claim 17, wherein, The difference between the aspect ratio of the first portion of the plurality of shunt acoustic resonators electrically connected to ground via the first electrode and the aspect ratio of the second portion of the plurality of shunt acoustic resonators electrically connected to ground via the second electrode reduces the difference in anti-resonance frequency among the plurality of shunt acoustic resonators.

19. The bulk acoustic resonator filter according to claim 17, wherein, The difference in anti-resonance frequency between the first portion of the plurality of shunt acoustic resonators electrically connected to ground via a first electrode and the second portion of the plurality of shunt acoustic resonators electrically connected to ground via a second electrode is less than the difference in resonance frequency between the first portion of the plurality of shunt acoustic resonators electrically connected to ground via a first electrode and the second portion of the plurality of shunt acoustic resonators electrically connected to ground via a second electrode.

20. The bulk acoustic resonator filter according to claim 17, wherein, The resonant frequency of the at least one series acoustic resonator is higher than the resonant frequency of each of the plurality of shunt acoustic resonators, and The difference in resonant frequency between the first portion of the plurality of shunt acoustic resonators electrically connected to ground via a first electrode and the second portion of the plurality of shunt acoustic resonators electrically connected to ground via a second electrode is less than the difference in resonant frequency between the highest resonant frequency of the plurality of shunt acoustic resonators and the resonant frequency of the at least one series acoustic resonator.

21. The bulk acoustic resonator filter according to claim 17, wherein, The first part and the second part are connected to each other by a corresponding first electrode or a corresponding second electrode, and the aspect ratio difference between the first part and the second part increases as the connection length between the first part and the second part increases.

22. A bulk acoustic wave resonator package, comprising: substrate; Cover, facing the substrate; A plurality of acoustic resonators, each of the plurality of acoustic resonators including a first electrode forming a resonant portion, a piezoelectric layer and a second electrode, the first electrode, the piezoelectric layer and the second electrode being stacked in a first direction extending from the substrate toward the cover, the first electrode, the piezoelectric layer and the second electrode being stacked in a stacked region and disposed between the substrate and the cover; A metal layer connects the plurality of acoustic resonators to each other; as well as A joining member surrounds the plurality of acoustic resonators in a circumferential direction perpendicular to the first direction and joins the cover to the substrate. Wherein, the aspect ratio of the stacked region of each of the plurality of acoustic resonators is equal to the ratio between the longest length of the stacked region in the direction of the extension of the longest side of the stacked region and the longest length of the stacked region in the direction perpendicular to the extension direction, and The aspect ratio of the acoustic resonator closer to the bonding member among the plurality of acoustic resonators is smaller than the aspect ratio of the other acoustic resonators farther away from the bonding member among the plurality of acoustic resonators, wherein the bonding member is grounded.

23. The bulk acoustic resonator package according to claim 22, wherein, The aspect ratio difference between two acoustic resonators in the plurality of acoustic resonators increases as the connection length of the metal layer connecting the two acoustic resonators to each other increases.

24. The bulk acoustic resonator package according to claim 22, wherein, The aspect ratio difference between two acoustic resonators in the plurality of acoustic resonators increases as the spacing between the metal layer connecting the two acoustic resonators to each other and the bonding member decreases.

25. The bulk acoustic resonator package according to claim 22, wherein, The plurality of acoustic resonators includes a first acoustic resonator, a second acoustic resonator, a third acoustic resonator, and a fourth acoustic resonator. The first acoustic resonator and the second acoustic resonator are connected to each other through a first portion of the metal layer. The third and fourth acoustic resonators are connected to each other through the second portion of the metal layer. The connection length of the first portion of the metal layer connecting the first and second acoustic resonators is longer than the connection length of the second portion of the metal layer connecting the third and fourth acoustic resonators. The aspect ratio difference between the first acoustic resonator and the second acoustic resonator is greater than the aspect ratio difference between the third acoustic resonator and the fourth acoustic resonator.

26. The bulk acoustic resonator package according to claim 22, wherein, The plurality of acoustic resonators includes a first acoustic resonator, a second acoustic resonator, a third acoustic resonator, and a fourth acoustic resonator. The first acoustic resonator and the second acoustic resonator are connected to each other through a first portion of the metal layer. The third and fourth acoustic resonators are connected to each other through the second portion of the metal layer. The distance between the first portion of the metal layer connecting the first and second acoustic resonators to each other and the bonding member is shorter than the distance between the second portion of the metal layer connecting the third and fourth acoustic resonators to each other and the bonding member. The aspect ratio difference between the first acoustic resonator and the second acoustic resonator is greater than the aspect ratio difference between the third acoustic resonator and the fourth acoustic resonator.

27. The bulk acoustic resonator package according to claim 22, wherein, The plurality of acoustic resonators includes a first acoustic resonator, a second acoustic resonator, a third acoustic resonator, and a fourth acoustic resonator. The first acoustic resonator and the second acoustic resonator are connected to each other through a first portion of the metal layer. The third and fourth acoustic resonators are connected to each other through the second portion of the metal layer. The first portion of the metal layer connecting the first and second acoustic resonators to each other, and the second portion of the metal layer connecting the third and fourth acoustic resonators to each other, are disposed at different heights relative to the substrate. The aspect ratios of the first acoustic resonator and the second acoustic resonator are different.

28. The bulk acoustic resonator package according to claim 22, wherein, The plurality of acoustic resonators includes a first acoustic resonator, a second acoustic resonator, and a third acoustic resonator that are electrically connected in series with each other. Of the first, second, and third acoustic resonators, the first acoustic resonator is closest to the joining member, and The aspect ratio difference between the first acoustic resonator and the second acoustic resonator is greater than the aspect ratio difference between the second acoustic resonator and the third acoustic resonator.

29. The bulk acoustic wave resonator package of claim 22, further comprising a first radio frequency (RF) port and a second RF port, wherein the plurality of acoustic wave resonators are electrically connected to the first RF port and the second RF port through the metal layer. in, The first radio frequency port is located near the first side of the substrate. The second radio frequency port is located near the second side of the substrate, and The aspect ratio of the acoustic resonator disposed closer to the third side of the substrate among the plurality of acoustic resonators is smaller than the aspect ratio of the other acoustic resonators disposed further away from the third side of the substrate among the plurality of acoustic resonators.

30. The bulk acoustic wave resonator package of claim 22, further comprising a ground port, wherein the plurality of acoustic wave resonators are electrically connected to the ground port through the metal layer. in, The aspect ratio of the acoustic resonator closer to the ground port electrical connection among the plurality of acoustic resonators is smaller than the aspect ratio of the other acoustic resonators farther away from the ground port electrical connection among the plurality of acoustic resonators.

31. The bulk acoustic resonator package according to claim 22, wherein, The joining member includes a conductive ring.

32. The bulk acoustic resonator package of claim 31, further comprising a shielding layer disposed on the surface of the cover facing the plurality of acoustic resonators and electrically connected to the bonding member.

33. A bulk acoustic resonator filter, comprising: The series section includes at least one series acoustic resonator that is connected in series between the first radio frequency port and the second radio frequency port. as well as Multiple shunt acoustic resonators are electrically connected to each other between the nodes of the series section and the ground port. Each of the plurality of shunt acoustic resonators includes: a resonant section comprising a first electrode, a piezoelectric layer, and a second electrode stacked in a first direction. In each of the plurality of shunt acoustic resonators, the first electrode, the piezoelectric layer, and the second electrode of the resonant section are stacked on top of each other in the stacked region. The aspect ratio of the stacked region of each of the plurality of shunt acoustic resonators is equal to the ratio between the longest length of the stacked region along the extension direction of the longest side of the stacked region and the longest length of the stacked region in a direction perpendicular to the extension direction. The bulk acoustic resonator filter also includes: A first metal layer, electrically connected to the first electrode of the plurality of shunt acoustic resonators; and The second metal layer is electrically connected to the second electrode of the plurality of shunt acoustic resonators. The plurality of shunt acoustic resonators include a first shunt acoustic resonator and a second shunt acoustic resonator electrically connected to each other in an anti-series connection manner, wherein the second metal layer electrically connects the second electrode of the first shunt acoustic resonator to the ground port, and the first metal layer electrically connects the first electrode of the second shunt acoustic resonator to the first electrode of the first shunt acoustic resonator. The aspect ratio of the second shunt acoustic resonator is different from that of the first shunt acoustic resonator. The aspect ratio of the first shunt acoustic resonator is smaller than that of the second shunt acoustic resonator.

34. The bulk acoustic resonator filter according to claim 33, wherein, The difference in aspect ratio between the first shunt acoustic resonator and the second shunt acoustic resonator cancels out the difference in parasitic impedance between the first shunt acoustic resonator and the second shunt acoustic resonator.

35. The bulk acoustic resonator filter according to claim 33, wherein, The difference in anti-resonance frequency between the first shunt acoustic resonator and the second shunt acoustic resonator is less than the difference in resonance frequency between the first shunt acoustic resonator and the second shunt acoustic resonator.

36. The bulk acoustic resonator filter according to claim 33, wherein, The difference in aspect ratio between the first shunt acoustic resonator and the second shunt acoustic resonator reduces the difference in their anti-resonance frequencies.

37. The bulk acoustic resonator filter according to claim 33, wherein, The plurality of shunt acoustic resonators further includes a third and a fourth shunt acoustic resonator electrically connected to each other in an anti-series connection manner, wherein a portion of the first metal layer electrically connects the first electrode of the third shunt acoustic resonator to the second metal layer, and the second metal layer electrically connects the portion of the first metal layer to the ground port, and the second metal layer electrically connects the second electrode of the fourth shunt acoustic resonator to the second electrode of the third shunt acoustic resonator. The aspect ratio of the fourth shunt acoustic resonator is equal to or substantially equal to the aspect ratio of the third shunt acoustic resonator.

38. A bulk acoustic resonator filter, comprising: The series section includes at least one series acoustic resonator that is connected in series between the first radio frequency port and the second radio frequency port. as well as Multiple shunt acoustic resonators are electrically connected in parallel between the first node of the series section and the first ground port. Each of the plurality of shunt acoustic resonators includes: a resonant section comprising a first electrode, a piezoelectric layer, and a second electrode stacked in a first direction. In each of the plurality of shunt acoustic resonators, the first electrode, the piezoelectric layer, and the second electrode of the resonant section are stacked on top of each other in the stacked region. The aspect ratio of the stacked region of each of the plurality of shunt acoustic resonators is equal to the ratio between the longest length of the stacked region along the extension direction of the longest side of the stacked region and the longest length of the stacked region in a direction perpendicular to the extension direction. The bulk acoustic resonator filter also includes: A first metal layer, electrically connected to the first electrode of the plurality of shunt acoustic resonators; and The second metal layer is electrically connected to the second electrode of the plurality of shunt acoustic resonators. The plurality of shunt acoustic resonators include a first shunt acoustic resonator and a second shunt acoustic resonator electrically connected to each other in an anti-parallel configuration. A second metal layer electrically connects the second electrode of the first shunt acoustic resonator to the first ground port, and a portion of the first metal layer electrically connects the first electrode of the second shunt acoustic resonator to the second metal layer. The second metal layer also electrically connects the portion of the first metal layer to the first ground port. The aspect ratio of the second shunt acoustic resonator is different from that of the first shunt acoustic resonator. The aspect ratio of the first shunt acoustic resonator is smaller than that of the second shunt acoustic resonator.

39. The bulk acoustic resonator filter according to claim 38, wherein, The difference in aspect ratio between the first shunt acoustic resonator and the second shunt acoustic resonator cancels out the difference in parasitic impedance between the first shunt acoustic resonator and the second shunt acoustic resonator.

40. The bulk acoustic resonator filter according to claim 39, further comprising a second plurality of shunt acoustic resonators electrically connected in series between the second node of the series section and the second ground port. in, Each of the second plurality of shunt acoustic resonators includes: a resonant portion comprising a first electrode, a piezoelectric layer, and a second electrode stacked in the first direction. In each of the second plurality of shunt acoustic resonators, the first electrode, the piezoelectric layer, and the second electrode of the resonant section are stacked on top of each other in the stacked region. The aspect ratio of the stacked region in each of the second plurality of shunt acoustic resonators is equal to the ratio between the longest length of the stacked region along the extension direction of its longest side and the longest length of the stacked region in a direction perpendicular to the extension direction. The at least one series acoustic resonator includes a series acoustic resonator electrically connected between the first node and the second node. The first metal layer is also electrically connected to the first electrode of the second plurality of shunt acoustic resonators. The second metal layer is also electrically connected to the second electrode of the second plurality of shunt acoustic resonators. The second plurality of shunt acoustic resonators further includes a third and a fourth shunt acoustic resonator electrically connected to each other in an anti-series connection manner, wherein the second metal layer electrically connects the second electrode of the third shunt acoustic resonator to the second ground port, and the first metal layer electrically connects the first electrode of the fourth shunt acoustic resonator to the first electrode of the third shunt acoustic resonator. The aspect ratio of the fourth shunt acoustic resonator is equal to or substantially equal to the aspect ratio of the third shunt acoustic resonator.

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