Acoustic wave device

Abstract

The embodiment of the utility model provides an acoustic wave device. The acoustic wave device comprises a substrate structure comprising a first surface and a second surface which are opposite to each other; the first resonant structure is formed on the first surface; the second resonant structure is formed on the second surface; the first bonding pad and the second bonding pad are located on the first surface, and the first bonding pad is connected with the first resonant structure; the second bonding pad is connected with the second resonant structure through a first conductive column penetrating through the substrate structure; the area of the first surface occupied by the first resonant structure is smaller than the area of the second surface occupied by the second resonant structure.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of electronic equipment, and in particular, to an acoustic wave device. Background Art

[0002] The RF front end is a vital part of the wireless communication system. It can be used to realize the mutual conversion between radio electromagnetic wave signals and digital signals. It mainly includes the transmitter and the receiver. As a key component of the wireless communication system, the performance of the RF front end directly affects the communication quality. With the development of technology, the RF front end is tending to be more integrated and comprehensive, which requires the device to be improved in many aspects such as performance and size.

[0003] In terms of device performance, with the evolution of communication generations, the demand for high-frequency products is also increasing, which puts higher requirements on the performance of acoustic wave devices. For example, low insertion loss, high suppression and strong power tolerance. In terms of size, with the popularity of mobile devices and consumers' increasing demand for portability, acoustic wave devices need to have smaller size and higher integration. This requires the design of acoustic wave devices to be more compact while maintaining high performance and reliability. How to prepare high-performance, small-volume and low-cost acoustic wave devices is a problem that needs to be solved urgently. Utility Model Content

[0004] In view of this, an embodiment of the present application provides an acoustic wave device, the acoustic wave device comprising:

[0005] a substrate structure comprising a first surface and a second surface opposite to each other;

[0006] A first resonant structure formed on the first surface;

[0007] A second resonant structure formed on the second surface;

[0008] A first pad and a second pad are located on the first surface, the first pad is connected to the first resonant structure; the second pad is connected to the second resonant structure via a first conductive column penetrating the substrate structure;

[0009] An area of ​​the first surface occupied by the first resonant structure is smaller than an area of ​​the second surface occupied by the second resonant structure.

[0010] In some embodiments, a ratio between an area of ​​the first surface occupied by the first resonant structure and an area of ​​the second surface occupied by the second resonant structure is 0.1-0.8.

[0011] In some embodiments, in a direction parallel to the first surface, a width of the second pad is greater than a width of the first conductive column.

[0012] In some embodiments, in a direction parallel to the first surface, a ratio between a width of the second pad and a width of the first conductive pillar is greater than or equal to 5.

[0013] In some embodiments, an area of ​​the second pad is greater than an area of ​​the first pad.

[0014] In some embodiments, a ratio between an area of ​​the second pad and an area of ​​the first pad is greater than or equal to 1.2.

[0015] In some embodiments, the acoustic wave device further comprises:

[0016] a packaging cover, located on a side of the second resonant structure away from the second surface;

[0017] The second resonant structure comprises two electrode layers stacked relatively to each other and a first piezoelectric layer located between the two electrode layers;

[0018] The packaging cover at least covers an overlapping area between the electrode layer and the first piezoelectric layer.

[0019] In some embodiments, the acoustic wave device further comprises:

[0020] a third pad located on a side of the package cover away from the substrate structure;

[0021] The packaging cover comprises a cover structure and a sidewall structure surrounding the cover structure; the sidewall structure is connected to the second surface of the substrate structure;

[0022] The third pad is connected to the second resonant structure via a second conductive column penetrating through the package cover.

[0023] In some embodiments, the substrate structure includes a substrate, a dielectric layer, and a second piezoelectric layer stacked in sequence;

[0024] The acoustic wave device further comprises a heat dissipation structure, wherein the heat dissipation structure is located between the substrate and the second pad;

[0025] The heat dissipation structure is connected to the first conductive column.

[0026] In some embodiments, the heat dissipation structure has a shape of any one of a cylinder, a cone, or a cuboid.

[0027] In some embodiments, the acoustic wave device further comprises:

[0028] an isolation structure located on the first surface;

[0029] The isolation structure is located between the adjacent first pad and the second pad.

[0030] In the acoustic wave device of the embodiment of the present application, when the first resonant structure and the second resonant structure are located on different surfaces, the first pad and the second pad are both arranged on the first surface, which can facilitate the connection between the acoustic wave device and the external device and simplify the subsequent connection process. The area of ​​the first surface occupied by the first resonant structure is smaller than the area of ​​the second surface occupied by the second resonant structure, which can reduce the overall size of the acoustic wave device on the one hand; on the other hand, it can relatively increase the ability of the second resonant structure to process high-power signals. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 The structure of the acoustic wave device in the embodiment of the present application is shown in FIG. Figure 1 ;

[0032] Figure 2 It is a schematic diagram of the layout of different surfaces of the acoustic wave device in the embodiment of the present application;

[0033] Figure 3 It is a perspective view of the layout of different surfaces of the acoustic wave device in the embodiment of the present application;

[0034] Figure 4 The structure of the acoustic wave device in the embodiment of the present application is shown in FIG. Figure 2 ;

[0035] Figure 5 The structure of the acoustic wave device in the embodiment of the present application is shown in FIG. Figure 3 ;

[0036] Figure 6 The structure of the acoustic wave device in the embodiment of the present application is shown in FIG. Figure 4 ;

[0037] Figure 7 The structure of the acoustic wave device in the embodiment of the present application is shown in FIG. Figure 5 ;

[0038] Figure 8 The structure of the acoustic wave device in the embodiment of the present application is shown in FIG. Figure 6 ;

[0039] Fig. 9 The structure of the acoustic wave device in the embodiment of the present application is shown in FIG. Figure 7 ;

[0040] Fig.10 The structure of the acoustic wave device in the embodiment of the present application is shown in FIG. Figure 8 ;

[0041] Fig.11 The structure of the acoustic wave device in the embodiment of the present application is shown in FIG. Figure 9 ;

[0042] Fig.12The structure of the acoustic wave device in the embodiment of the present application is shown in FIG. Figure 10 ;

[0043] Figures 13 to 18 Schematic diagram of the steps of forming an acoustic wave device in an embodiment of the present application. DETAILED DESCRIPTION

[0044] The following will be combined with the embodiments of the present application and the accompanying drawings to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0045] In the following description, a large number of specific details are given to provide a more thorough understanding of the present application. However, it is obvious to those skilled in the art that the present application can be implemented without one or more of these details. In other examples, in order to avoid confusion with the present application, some technical features known in the art are not described; that is, all features of the actual embodiments are not described here, and well-known functions and structures are not described in detail.

[0046] The purpose of the terms used herein is only to describe specific embodiments and is not intended to be limiting of the present application. When used herein, the singular forms "one", "an" and "said / the" are also intended to include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "consisting of" and / or "comprising", when used in this specification, determine the presence of the features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or groups. When used herein, the term "and / or" includes any and all combinations of the relevant listed items.

[0047] In order to thoroughly understand the present application, detailed steps and detailed structures will be presented in the following description to illustrate the technical solution of the present application. The preferred embodiments of the present application are described in detail below, but in addition to these detailed descriptions, the present application may also have other implementation methods.

[0048] In wireless communication systems, surface acoustic wave (SAW) devices and bulk acoustic wave (BAW) devices are usually used as filters. Since the propagation loss of sound waves on the solid surface is small, SAW filters can achieve a high quality factor filtering effect. And SAW filters also have the advantages of simple preparation process and easy miniaturization. BAW filters use the propagation and reflection of bulk acoustic waves in piezoelectric materials to achieve filtering functions. When sound waves propagate inside the material, the energy loss is small, and BAW filters have low insertion loss. In the high frequency band, this low insertion loss characteristic can ensure that the signal has less power loss when passing through the filter, thereby improving the efficiency of the communication system. And BAW filters also have the advantages of large out-of-band attenuation and good temperature stability. How to give full play to the advantages of different filters, further improve the performance of acoustic wave devices, and reduce the size of acoustic wave devices is one of the important directions of current research.

[0049] In view of this, an embodiment of the present application provides an acoustic wave device, such as Figure 1 As shown, the acoustic wave device includes: a substrate structure 101, a first resonant structure 102, and a second resonant structure 103. The substrate structure includes a first surface and a second surface opposite to each other; the first resonant structure 102 is formed on the first surface; and the second resonant structure 103 is formed on the second surface. The acoustic wave device also includes a first pad 104 and a second pad 105 located on the first surface, the first pad 104 is connected to the first resonant structure 102; and the second pad 105 is connected to the second resonant structure 103 through a first conductive column 106 that penetrates the substrate structure. The area of ​​the first surface occupied by the first resonant structure 102 is smaller than the area of ​​the second surface occupied by the second resonant structure 103.

[0050] The first pad is connected to the first resonant structure, and is used to realize the electrical connection between the first resonant structure and the external device. The second pad is connected to the second pad through the first conductive column, and is used to realize the electrical connection between the second resonant structure and the external device. In the case where the first resonant structure and the second resonant structure are located on different surfaces, compared with respectively setting the first pad connected to the first resonant structure and the second pad connected to the second resonant structure on the first surface and the second surface, setting both the first pad and the second pad on the first surface can facilitate the connection between the acoustic wave device and the external device and simplify the subsequent connection process.

[0051] Compared with directly setting the second pad on the periphery of the first pad, the area of ​​the first surface occupied by the first resonant structure is reduced, so that the area of ​​the first surface occupied by the first resonant structure is smaller than the area of ​​the second surface occupied by the second resonant structure. On the one hand, the overall size of the acoustic wave device can be reduced; on the other hand, the ratio of the area of ​​the second surface occupied by the second resonant structure to the area of ​​the first surface occupied by the first resonant structure is increased, so that the ability of the second resonant structure to process high-power signals is better than that of the first resonant structure.

[0052] In one embodiment, if Figure 2 As shown, the area of ​​the first surface occupied by the first resonant structure, i.e., the first area S1, is the difference between the area of ​​the rectangle defined by the outer edges of the four first pads 104 and the area of ​​the four first pads 104. The area of ​​the second surface occupied by the second resonant structure, i.e., the second area S2, is the difference between the area of ​​the rectangle defined by the edges of the four second pads 105 and the area of ​​the four second pads 105. According to the following heat conduction formula (1), the heat dissipation is proportional to the heat dissipation area. Under the same other conditions, the larger the heat dissipation area, the stronger the heat dissipation capacity.

[0053]

[0054] Where Q is the amount of heat (W), △T is the temperature difference (K), R is the thermal resistance (K / W), L is the thickness (M), and λ is the thermal conductivity S represents area (m 2 ).

[0055] like Figure 3 As shown, the ratio of the area of ​​the first surface occupied by the first resonant structure to the area of ​​the second surface occupied by the second resonant structure is less than 1, that is, S1 / S2<1. Compared with the first resonant structure, the second resonant structure has a larger area, better heat dissipation capability, and is more suitable for processing high-power signals. Since the transmitter filter is located at the output end of the power amplifier, the signal power it processes is higher than the signal power of the receiver filter. The first resonant structure can be used as a receiver filter, and the second resonant structure can be used for a transmitter filter, further giving play to the device characteristics of the first resonant structure and the second resonant structure.

[0056] It should be noted that the substrate structure in the embodiment of the present application is not a bonded substrate. Since the bonded substrate is formed by bonding different substrate structures or multiple identical substrates, its bonding quality can directly affect the performance and reliability of the acoustic wave device. If there are bubbles, impurities or incompletely bonded areas during the bonding process, it may cause stress concentration, increased thermal resistance or reduced conductivity at the bonding interface. These problems will further affect the heat dissipation performance, electrical performance and reliability of the acoustic wave device, and may even cause problems such as device failure.

[0057] In some embodiments, a ratio between an area of ​​the first surface occupied by the first resonant structure and an area of ​​the second surface occupied by the second resonant structure is 0.1-0.8.

[0058] Continue to refer Figure 3 The ratio of the area of ​​the first surface occupied by the first resonant structure to the area of ​​the second surface occupied by the second resonant structure, that is, the ratio S1 / S2 of the first area to the second area, is 0.1-0.8.

[0059] In some embodiments, in a direction parallel to the first surface, a width of the second pad is greater than a width of the first conductive column.

[0060] In the direction parallel to the first surface, that is, along the horizontal extension direction of the substrate structure, the width of the second pad is greater than the width of the first conductive column. Since the width of the second pad connected to the first conductive column is larger, its heat dissipation capacity is better, which can reduce the thermal stress caused by heat concentration and reduce the potential thermal damage to the acoustic wave device. The material of the first conductive column and the second pad can be selected from metal materials with good heat dissipation performance and good electrical conductivity. For example, copper, silver, gold and aluminum.

[0061] In one embodiment, if Figure 4 As shown, along the horizontal direction, the width W1 of the second pad is greater than the width W2 of the first conductive column.

[0062] In some embodiments, in a direction parallel to the first surface, a ratio between a width of the second pad and a width of the first conductive pillar is greater than or equal to 5.

[0063] Continue to refer Figure 4 , a ratio of a width W1 of the second pad to a width W2 of the first conductive column satisfies: W1 / W2≥5.

[0064] In some embodiments, an area of ​​the second pad is greater than an area of ​​the first pad.

[0065] In one embodiment, the area of the first surface occupied by the first resonant structure is smaller than the area of the second surface occupied by the second resonant structure. The area of the first pad connected to the first resonant structure is set to be smaller than the area of the second pad connected to the second resonant structure, that is, the area of the second pad is larger than the area of the first pad. Since the pads help to disperse and conduct the heat generated by the device during operation. Especially in the case of high power or long-term operation, the pads can effectively transfer the heat to the Printed Circuit Board (PCB). The second pad with a larger area has better heat dissipation ability. In the case where the second resonant structure needs to process high-power signals while the first resonant structure does not need to process high-power signals for a long time, increasing the area of the second pad can enhance the thermal stability of the second resonant structure, and thus enhance the stability and reliability of the acoustic wave device. Exemplarily, continuing to refer to Figure 3 , the area S3 of the first pad 104 is smaller than the area S4 of the second pad 105, that is, S3 < S4. It can be understood that when both the first pad and the second pad are set as squares, the side length of the second pad is greater than the side length of the first pad.

[0066] In some embodiments, the ratio between the area of the second pad and the area of the first pad is greater than or equal to 1.2.

[0067] In one embodiment, the ratio between the area of the second pad and the area of the first pad, that is, S4 / S3 ≥ 1.2.

[0068] In some embodiments, the acoustic wave device further includes: a packaging cover. The packaging cover is located on the side of the second resonant structure away from the second surface; the second resonant structure includes two electrode layers stacked relatively and a first piezoelectric layer located between the two electrode layers; the packaging cover covers at least the overlapping area between the electrode layer and the first piezoelectric layer.

[0069] As Figure 5 shown, the second resonant structure 103 includes two electrode layers 501 stacked relatively and a first piezoelectric layer 502 located between the two electrode layers 501. Its laminated thin-film structure enables the second resonant structure 103 to have better power tolerance. The acoustic wave device further includes a packaging cover 503 disposed on the second resonant structure 103, and the packaging cover 503 covers at least the overlapping area between the two electrode layers 501 and the first piezoelectric layer 502. The packaging cover 503 can protect the second resonant structure 103 and reduce the influence of subsequent processes on the second resonant structure during the manufacturing process of the acoustic wave device, which is beneficial to improving the performance of the acoustic wave device.

[0070] In some embodiments, the acoustic wave device also includes: a third solder pad located on a side of the packaging cover away from the substrate structure; the packaging cover includes a cover body structure and a side wall structure surrounding the cover body structure; the side wall structure is connected to the second surface of the substrate structure; the third solder pad is connected to the second resonant structure through a second conductive column that passes through the packaging cover.

[0071] In one embodiment, if Figure 6 As shown, the package cover 503 includes a cover structure 511 and a sidewall structure 512 surrounding the cover structure 511. The cover structure 511 is not in contact with the second surface of the substrate structure 101, and the sidewall structure 512 is in contact with the second surface of the substrate structure 101. The package cover 503 forms a cavity with the second resonant structure, and the package cover and the electrode layer are not in direct contact, which is conducive to further improving the performance of the second resonant structure.

[0072] Continue to refer Figure 6 The acoustic wave device further includes a third pad 601 disposed on the package cover 503. The third pad 601 is connected to the second resonant structure through a second conductive column 602. The second conductive column 602 penetrates the sidewall structure 512 of the package cover.

[0073] Further setting a third pad connected to the second resonant structure on the package cover can increase the flexibility of the design on the one hand, so that the second resonant structure can be connected to the external device through the second pad on the upper side of the substrate structure, or through the third pad on the lower side of the substrate structure. On the other hand, the additional second conductive column and third pad increase the heat dissipation channel of the second resonant structure, further improving the heat dissipation capacity of the second resonant structure. Among them, the material of the second conductive column and the third pad can be selected from metal materials with good heat dissipation performance and good conductivity. For example, copper, silver, gold and aluminum.

[0074] In some embodiments, Figure 7 As shown, the substrate structure 101 includes a substrate 701, a dielectric layer 702 and a second piezoelectric layer 703 stacked in sequence; the acoustic wave device also includes a heat dissipation structure, which is located between the substrate and the second pad; and the heat dissipation structure is connected to the first conductive column.

[0075] Adding a heat dissipation structure between the second pad and the substrate can further increase the heat dissipation channel and heat dissipation area of ​​the second resonant structure, thereby improving the heat dissipation capacity of the second resonant structure. It should be noted that the projection of the heat dissipation structure on the first surface is covered by the projection of the second pad on the first surface, that is, the heat dissipation structure and the projection of the first resonant structure on the first surface do not overlap, and will not have an adverse effect on the performance of the first resonant structure. In addition, it can be understood that when a heat dissipation structure is provided, the second conductive column may not pass through the entire substrate structure, and the heat dissipation structure and the second conductive column as a whole pass through the substrate structure.

[0076] In some embodiments, the heat dissipation structure has a shape of any one of a cylinder, a cone, or a cuboid.

[0077] For example, Figure 8 As shown, the heat dissipation structure 801 is located on the substrate 701, that is, located on the side of the substrate 701 away from the second resonant structure, and the thickness of the heat dissipation structure 801 is the same as the thickness of the dielectric layer 702. The upper surface of the heat dissipation structure 801 is connected to the first conductive column and the second piezoelectric layer 703, and is not directly connected to the second pad 105.

[0078] For example, Fig. 9 As shown, the heat dissipation structure 901 is located on the substrate 701, that is, located on the side of the substrate 701 away from the second resonant structure, and the thickness of the heat dissipation structure 901 is the same as the sum of the thickness of the dielectric layer 702 and the second piezoelectric layer 703. The upper surface of the heat dissipation structure 901 is directly connected to the second pad 105.

[0079] For example, Fig.10 As shown, the heat dissipation structure 1001 can replace part of the second piezoelectric layer 703, and its thickness is less than the thickness of the second piezoelectric layer 703. The upper surface of the heat dissipation structure 1001 is directly connected to the second pad, and the lower surface is connected to the second piezoelectric layer 702.

[0080] For example, Fig.11 As shown, the heat dissipation structure 1101 may be a cone, and its cross-section shape is a trapezoid. The heat dissipation structure 1101 is located between the substrate 701 and the second pad 105, and its thickness is the same as the sum of the thickness of the dielectric layer 702 and the second piezoelectric layer 703. The upper surface of the heat dissipation structure 1101 is directly connected to the second pad 105, and the lower surface is connected to the second conductive column.

[0081] In some embodiments, the material of the heat dissipation structure can be selected from metal materials with good heat dissipation performance and good electrical conductivity. For example, copper, silver, gold and aluminum. The material of the substrate can be silicon, silicon carbide, quartz, sapphire, etc. The material of the dielectric layer can be silicon dioxide, silicon nitride, etc., which can reduce the influence of temperature on the performance of the first resonant structure and improve the performance of the acoustic wave device. The material of the second piezoelectric layer can be lithium tantalate (LiTaO3) or lithium niobate (LiNbO3).

[0082] In some embodiments, the acoustic wave device further includes an isolation structure located on the first surface; the isolation structure is located between adjacent first pads and second pads.

[0083] The isolation structure is disposed between the adjacent first pad and the second pad, and is not connected to the first pad or the second pad. The isolation structure can be formed using metal materials, and the metal isolation structure can effectively reduce electromagnetic interference between the first pad and the second pad, and improve the stability and reliability of the acoustic wave device.

[0084] For example, Fig.12 As shown, the isolation structure 1201 is disposed on the first surface and is located between the adjacent first pad 104 and the second pad 105. In one embodiment, it may be a ring structure surrounding the entire first resonant structure.

[0085] This application also provides the following examples:

[0086] like Fig.13 As shown, a dielectric layer 702 and a second piezoelectric layer 703 are sequentially formed on a provided substrate 701. The substrate 701, the dielectric layer 702 and the second piezoelectric layer 703 together constitute a substrate structure 101. A first resonant structure 102 and a first pad 104 are formed on the second piezoelectric layer 703; and a first through hole 1301 penetrating the substrate structure 101 is formed.

[0087] It should be noted that the process of forming the first through hole is not limited to the current step, and it can be completed after forming the substrate structure and before forming the second resonant structure.

[0088] like Fig.14 As shown, a fixing process is performed on the upper surface of the first resonant structure. Specifically, the wafer including the substrate structure and the first resonant structure is temporarily bonded to a thicker handle wafer 1401 for subsequent processing or treatment.

[0089] like Fig.15 As shown, Fig.14 The structure shown is turned over as a whole, with the first surface of the substrate structure 101 facing downward, and a first conductive pillar 106 is formed in the first through hole.

[0090] like Fig.16 As shown, a second resonant structure 103 is formed on the second surface of the substrate structure 101 , and may specifically include two electrode layers and a second piezoelectric layer therebetween.

[0091] like Fig.17As shown, a packaging cover 503 is formed on the second resonant structure 103, and the packaging cover at least covers the overlapping area between the two electrode layers and the first piezoelectric layer of the second resonant structure. In addition, the packaging cover and the second resonant structure form a cavity. On the one hand, the packaging cover can protect the second resonant structure, reduce the impact of subsequent processes on the second resonant structure during the manufacture of the acoustic wave device, and help improve the performance of the acoustic wave device. On the other hand, the packaging cover and the second resonant structure form a cavity, and there is no direct contact between the packaging cover and the electrode layer, which is conducive to further improving the performance of the second resonant structure.

[0092] like Fig.18 As shown, Fig.17 The structure shown is turned over as a whole, with one side of the carrier wafer 1401 facing upward, and the temporarily bonded carrier wafer 1401 is removed. Then, a second pad 105 connected to the first conductive column 106 is formed on the periphery of the first resonant structure 102, and solder bumps 1801 are formed on the first pad 104 and the second pad 105 to serve as ports for connecting to the PBC board.

[0093] Continue to refer Fig.18 , the first resonant structure 102 can be a SAW filter. Due to the small propagation loss of sound waves on the solid surface, the SAW filter can achieve a high-quality filtering effect, and the SAW filter also has the advantages of simple preparation process and easy miniaturization. The second resonant structure 103 can be a BAW filter, which has the advantages of small insertion loss, large out-of-band attenuation, and good temperature stability in high-frequency bands (such as 5G communications). Exemplarily, the second resonant structure is a film bulk acoustic wave (FBAR) filter, which has a laminated film structure with good power tolerance. Taking advantage of the fact that the SAW filter is easy to miniaturize, the layout area of ​​the SAW filter is set to be smaller than the layout area of ​​the FBAR filter, and the second pad connected to the FBAR filter is set next to the first pad connected to the SAW filter, which effectively increases the relative area of ​​the FBAR filter, further improves the thermal stability of the FBAR filter, and improves its ability to handle high-power signals.

[0094] It should be noted that the second resonant structure may also be a solid-mounted bulk acoustic wave filter (SMR), etc. The acoustic wave device in the embodiment of the present application may be any one of a duplexer, a multiplexer and a dual filter.

[0095] It should be understood that the "one embodiment" mentioned throughout the specification means that the specific features, structures or characteristics related to the embodiment are included in at least one embodiment of the present application. Therefore, "in one embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner. It should be understood that in various embodiments of the present application, the size of the sequence number of the above-mentioned processes does not mean the order of execution, and the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present application. The above-mentioned sequence numbers of the embodiments of the present application are only for description and do not represent the advantages and disadvantages of the embodiments.

[0096] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An acoustic wave device, characterized in that: include: a substrate structure comprising a first surface and a second surface opposite to each other; A first resonant structure formed on the first surface; A second resonant structure formed on the second surface; A first pad and a second pad located on the first surface, wherein the first pad is connected to the first resonant structure; The second pad is connected to the second resonant structure via a first conductive column penetrating through the substrate structure; An area of ​​the first surface occupied by the first resonant structure is smaller than an area of ​​the second surface occupied by the second resonant structure.

2. The acoustic wave device according to claim 1, characterized in that A ratio between an area of ​​the first surface occupied by the first resonant structure and an area of ​​the second surface occupied by the second resonant structure is 0.1-0.

8.

3. The acoustic wave device according to claim 1, characterized in that In a direction parallel to the first surface, a width of the second pad is greater than a width of the first conductive column.

4. The acoustic wave device according to claim 3, characterized in that In a direction parallel to the first surface, a ratio between a width of the second pad and a width of the first conductive column is greater than or equal to 5.

5. The acoustic wave device according to claim 1, characterized in that An area of ​​the second pad is greater than an area of ​​the first pad.

6. The acoustic wave device according to claim 5, characterized in that A ratio of an area of ​​the second pad to an area of ​​the first pad is greater than or equal to 1.

2.

7. The acoustic wave device according to claim 1, characterized in that Also includes: a packaging cover, located on a side of the second resonant structure away from the second surface; The second resonant structure comprises two electrode layers stacked relatively to each other and a first piezoelectric layer located between the two electrode layers; The packaging cover at least covers an overlapping area between the electrode layer and the first piezoelectric layer.

8. The acoustic wave device according to claim 7, characterized in that Also includes: a third pad located on a side of the package cover away from the substrate structure; The packaging cover comprises a cover structure and a side wall structure surrounding the cover structure; The sidewall structure is connected to the second surface of the substrate structure; The third pad is connected to the second resonant structure via a second conductive column penetrating through the package cover.

9. The acoustic wave device according to claim 1, characterized in that The substrate structure comprises a substrate, a dielectric layer and a second piezoelectric layer stacked in sequence; The acoustic wave device further comprises a heat dissipation structure, wherein the heat dissipation structure is located between the substrate and the second pad; The heat dissipation structure is connected to the first conductive column.

10. The acoustic wave device according to claim 9, characterized in that The shape of the heat dissipation structure includes any one of a cylinder, a cone or a cuboid.

11. The acoustic wave device according to claim 1, characterized in that Also includes: an isolation structure located on the first surface; The isolation structure is located between the adjacent first pad and the second pad.

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