Surface acoustic wave filter and manufacturing method thereof

Abstract

The invention provides a surface acoustic wave filter and a manufacturing method thereof, and the surface acoustic wave filter comprises a substrate which is provided with a plurality of first grooves, and each first groove is internally provided with an interconnection layer; the plurality of resonators are arranged on the substrate; the plurality of resonators comprise spaced resonators and adjacent resonators, each resonator comprises a plurality of interdigital electrodes and bus bars connected with the interdigital electrodes, and the bus bars of the spaced resonators are electrically connected with the interconnection layer in the first groove so that the spaced resonators are electrically connected. By arranging the interconnection layer in the substrate, a traditional mode of forming a span bridge through dielectric layers such as Poly / Oxide and performing connection by means of PAD metal is replaced, the interlayer structure of the device is simplified, the production complexity is reduced, and the production period is effectively shortened.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and specifically to a surface acoustic wave filter and its fabrication method. Background Technology

[0002] Surface Acoustic Wave (SAW) technology has been widely used in communication equipment since the 1960s. Traditional SAW filters typically rely on a single acoustic mode, and while they perform well in terms of frequency selectivity and insertion loss, their limitations in bandwidth, selectivity, and miniaturization are becoming increasingly apparent. With the rapid development of wireless communication, especially the promotion of 4G and 5G technologies, the performance requirements for filters are constantly increasing, creating market conditions for the emergence of dual-mode coupled surface acoustic wave (DMS) filters.

[0003] However, the SAW DMS longitudinally coupled filter design requires an isolation layer (ISO) as a bridge medium for interconnection, which increases the complexity and cost of the process. Summary of the Invention

[0004] The problem solved by this invention is the complexity of the manufacturing process of existing surface acoustic wave filters.

[0005] To address the above problems, the present invention provides a surface acoustic wave (SAW) filter, the SAW filter comprising: A substrate having a plurality of first grooves, each of which contains an interconnect layer; A plurality of resonators are disposed on the substrate, the plurality of resonators including spaced resonators and adjacent resonators; Each of the resonators includes a plurality of interdigital electrodes and a busbar connected to the plurality of interdigital electrodes. The busbar of the spacer resonator is electrically connected to the interconnect layer in the first groove to make the spacer resonator electrically connected.

[0006] Optionally, the first groove is located below the busbar.

[0007] Optionally, a first dielectric layer is provided between the busbar and the first groove, and an opening exposing the interconnect layer is provided at the position corresponding to the busbar of the spacer resonator and the first groove, so that the busbar of the spacer resonator is electrically connected through the interconnect layer, and the adjacent resonators are insulated from each other.

[0008] Technical effect: By setting an opening in the exposed interconnect layer in the first dielectric layer, the busbars of the spaced resonators are electrically connected through the interconnect layer, ensuring the reliability and stability of the required electrical connection. Furthermore, by utilizing the insulating properties of the first dielectric layer, physical isolation and electrical insulation of adjacent resonators are achieved. Structurally, this avoids the risk of signal crosstalk or short circuit caused by parasitic capacitance and leakage current between adjacent resonators, thereby ensuring a circuit structure that interconnects between spaced resonators and insulates between adjacent resonators.

[0009] Optionally, the interdigital electrode has a mass block at its end, which is located on the upper surface of the interdigital electrode, or on the side of the interdigital electrode, or at the bottom of the interdigital electrode.

[0010] When the mass block is located at the bottom of the interdigitated electrode, the substrate is also provided with a second groove, and the mass block is located in the second groove.

[0011] Technical effect: When the mass block is located at the bottom of the interdigital electrode, it can act as a conductive bridging component within the second groove to connect the interdigital electrodes, thus forming a complete circuit between the originally separate electrode segments. The cooperation between the second groove and the mass block achieves continuity in the connection of the interdigital electrodes, avoiding structural redundancy caused by winding or bridging in traditional electrode wiring.

[0012] Optionally, the first groove and the second groove are made in the same process.

[0013] Technical benefits: It can simplify the process flow, reduce repetitive operations in core processes such as photolithography and etching, and reduce the risk of process deviation caused by the accumulation of multiple processes, which is conducive to improving product consistency and yield.

[0014] Optionally, the mass block is made of metal or a dielectric material.

[0015] When the mass block is made of metal, the interconnect layer and the mass block are manufactured in the same process.

[0016] Technical benefits: By fabricating the interconnect layer and the mass block in the same process, the repetitive operations of photolithography, deposition and other steps are reduced, the production process is shortened, the process cost and error accumulation risk are reduced, and the product consistency during mass production is improved.

[0017] This application also provides a method for manufacturing a surface acoustic wave filter, the method comprising: Provide substrate; A plurality of first grooves are formed on the substrate, and an interconnect layer is formed in each first groove; A plurality of resonators are disposed on the substrate, the plurality of resonators including spaced resonators and adjacent resonators, wherein each of the resonators includes a plurality of interdigital electrodes and a busbar connected to the plurality of interdigital electrodes, and the busbar of the spaced resonator is electrically connected to an interconnect layer in the first groove to electrically connect the spaced resonator.

[0018] Optionally, arranging multiple resonators on the substrate includes: A first dielectric layer is disposed within each of the first grooves; An opening is provided on the first dielectric layer to expose the interconnect layer; The busbar of the spacer resonator is disposed within the opening so that the busbar of the spacer resonator is electrically connected through the interconnect layer, and the adjacent resonators are insulated from each other.

[0019] Optionally, before fabricating multiple resonators on the substrate, the fabrication method further includes: A plurality of second grooves are provided on the substrate, wherein the second grooves and the first grooves do not overlap; A mass block is placed in each of the second grooves.

[0020] Optionally, the provision of the plurality of first grooves on the substrate and the provision of the plurality of second grooves on the substrate are manufactured in the same process.

[0021] The surface acoustic wave filter provided in this application includes a substrate and multiple resonators. The substrate has multiple first grooves, and each first groove has an interconnect layer. The busbar of the spacer resonator is electrically connected to the interconnect layer in the first groove to make the spacer resonator electrically connected. This replaces the traditional method of forming a bridge through a dielectric layer such as Polyimide / Oxide and connecting it with PAD metal, which simplifies the interlayer structure of the device, reduces the complexity of production, and effectively shortens the production cycle. Attached Figure Description

[0022] Figure 1 A top view of the surface acoustic wave filter provided in an embodiment of this application; Figure 2 for Figure 1 The cross-sectional view of the surface acoustic wave filter shown is along the AA direction; Figure 3 for Figure 1 The top view shown is of the surface acoustic wave filter without a resonator. Figure 4 for Figure 3 The cross-sectional view of the surface acoustic wave filter shown is along the BB direction; Figure 5 for Figure 4The diagram shows a schematic of the structure of a surface acoustic wave filter with a first dielectric layer. Figure 6 for Figure 1 The diagram shows another structural schematic of a surface acoustic wave filter. Figure 7 for Figure 1 The diagram shown illustrates the structure of a surface acoustic wave filter including a PAD metal layer and a passivation layer. Figure 8 A schematic flowchart illustrating the fabrication method of the surface acoustic wave filter provided in this application embodiment; Figure 9 for Figure 8 The flowchart shown illustrates the process of setting up multiple resonators in the manufacturing method.

[0023] Explanation of reference numerals in the attached figures: 1. Surface acoustic wave filter; 11. Substrate; 12. Resonator; 13. Interconnect layer; 14. First dielectric layer; 15. Mass block; 16. Second dielectric layer; 18. PAD metal layer; 19. Passivation layer; 111. First groove; 112. Second groove; 121. Interdigitated electrode; 122. Busbar. Detailed Implementation

[0024] To make the above-mentioned objectives, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below.

[0025] Please see Figure 1 and Figure 2 , Figure 1 This is a top view of the surface acoustic wave filter provided in the embodiments of this application. Figure 2 for Figure 1 The image shows a cross-sectional view of a surface acoustic wave (SAW) filter along the AA direction. This application provides a SAW filter 1, which includes a substrate 11 and multiple resonators 12. The substrate 11 has multiple first grooves 111, each containing an interconnect layer 13. The multiple resonators 12 are disposed on the substrate 11, including spaced resonators and adjacent resonators. Each resonator 12 includes multiple interdigitated electrodes 121 and busbars 122 connected to the interdigitated electrodes 121. The busbars 122 of the spaced resonators 12 are electrically connected to the interconnect layer 13 within the first grooves 111, thus electrically connecting the spaced resonators 12. The interconnect layer 13 replaces the traditional method of forming bridges through dielectric layers such as Polyimide / Oxide and connecting them using PAD metal, simplifying the interlayer structure of the device, reducing manufacturing complexity, and effectively shortening the production cycle.

[0026] It should be noted that a spaced resonator can be understood as multiple resonators 12 that are spaced apart by at least one resonator, and an adjacent resonator can be understood as multiple resonators 12 that are adjacent to each other and are not spaced apart.

[0027] In some embodiments, the first groove 111 is located below the busbar 122, or, in other embodiments, the first groove 111 is located in the region of the busbar 122 away from the interdigitated electrode 121. These two different positional arrangements can accommodate different structural design and functional requirements.

[0028] Please continue reading. Figures 3 to 5 , Figure 3 for Figure 1 The top view shown is of the surface acoustic wave filter without a resonator. Figure 4 for Figure 3 The cross-sectional view of the surface acoustic wave filter shown is along the BB direction. Figure 5 for Figure 4 The diagram shows a surface acoustic wave (SAW) filter with a first dielectric layer. A first dielectric layer 14 is provided between the busbar 122 and the first groove 111. At the corresponding positions of the busbar 122 and the first groove 111 of the spacer resonators, openings are provided to expose the interconnect layer 13. The busbar 122 is positioned within these openings and contacts the interconnect layer 13, allowing the busbars 122 of the spacer resonators to be electrically connected through the interconnect layer 13. Adjacent resonators are insulated from each other. The design of filling the first groove 111 with the first dielectric layer 14 and forming openings provides stable protection for the interconnect layer 13 while also enabling electrical connection between the busbars 122 of the spacer resonators and the interconnect layer 13, ensuring the reliability and stability of the required electrical connections. Furthermore, the busbars 122 of adjacent resonators 12 do not contact the interconnect layer 13, thus insulating adjacent resonators 12 from each other. This application embodiment utilizes the insulating properties of the dielectric layer to achieve physical isolation and electrical insulation between adjacent resonators 12, structurally avoiding the risk of signal crosstalk or short circuit between adjacent resonators 12 due to parasitic capacitance and leakage current, thereby ensuring a circuit structure in which spaced resonators 12 are interconnected and adjacent resonators 12 are insulated.

[0029] It is understood that each first groove 111 may include multiple interconnected interconnect layers 13, and the size and thickness of each interconnect layer 13 can be set according to the actual situation, as long as the thickness of the interconnect layer 13 is not higher than the depth of the first groove 111.

[0030] The interdigital electrode 121 has a mass block 15 at its end. The mass block 15 is located on the upper surface of the interdigital electrode 121, or on the side of the interdigital electrode 121, or at the bottom of the interdigital electrode 121.

[0031] In some embodiments, when the mass block 15 is located at the bottom of the interdigital electrode 121, the substrate 11 is further provided with a second groove 112, and the mass block 15 is located in the second groove 112. The sound velocity of the interdigital electrode 121 can be adjusted by utilizing the size and material characteristics of the mass block 15, thereby suppressing the propagation of transverse modes, thus achieving the effect of suppressing transverse spurious signals in the band and improving the frequency selectivity and operating stability of the filter.

[0032] It should be noted that the size and thickness of the mass block 15 can be flexibly adjusted according to the spacing and disconnection length of the interdigital electrodes 121. It is only necessary to ensure that the contact area with the electrodes is sufficient and the connection resistance is low to ensure the integrity and stability of the surface acoustic wave signal during electrode transmission.

[0033] In some embodiments, the first groove 111 and the second groove 112 are manufactured in the same process. This simplifies the process flow, reduces repetitive operations in core processes such as photolithography and etching, and reduces the risk of process deviations caused by the accumulation of multiple processes, which is beneficial to improving product consistency and yield. In addition, process merging can reduce equipment use, material consumption, and manual intervention, significantly reducing production costs.

[0034] In some embodiments, the mass block 15 is a metal or dielectric material. When the mass block 15 is a metal material, the interconnect layer 13 and the mass block 15 are manufactured in the same process. It is understood that process merging reduces repetitive operations such as photolithography and deposition, shortens the production process, reduces process costs and the risk of error accumulation, and helps improve product consistency during mass production.

[0035] In some embodiments, the interconnect layer 13 and the mass block 15 are made of different materials to facilitate configuration according to actual conditions. For example, if the interconnect layer 13 needs to focus on the electrical connection stability with the busbar 122 of the spacer resonator 12, a material with better conductivity can be selected to reduce contact resistance and improve signal transmission efficiency. On the other hand, if the mass block 15 focuses on supporting the interdigital electrodes 121 and enhancing structural stability, a material with moderate mechanical stiffness can be selected to optimize stress distribution and structural load-bearing capacity. In this way, the configuration of different materials can achieve functional complementarity, thereby improving the overall performance of the device.

[0036] It should be noted that when the busbar 122 and interdigitated electrodes 121 are manufactured in the same process, they can be seamlessly connected. Furthermore, the complete consistency of material composition and manufacturing process not only significantly reduces interfacial contact resistance, ensuring ultra-low electrical loss and high-efficiency signal transmission, but also significantly improves bonding strength, effectively resisting the risk of contact failure caused by thermal expansion and contraction stress due to temperature changes and external mechanical stress. This significantly enhances the structural stability and electrical reliability of the device during long-term operation.

[0037] In some embodiments, the busbar 122, interdigitated electrodes 121, and mass block 15 are made of the same material. The contact interface of these homogeneous materials eliminates potential barriers or impedance abrupt changes caused by material differences, ensuring continuity and low loss during current conduction among the three components. This significantly reduces contact resistance, minimizes energy attenuation during signal transmission, and effectively maintains the integrity and transmission efficiency of the surface acoustic wave signal. Furthermore, material uniformity simplifies the manufacturing process, reduces process switching costs and error accumulation due to material changes, and effectively controls manufacturing costs while improving consistency in mass production.

[0038] In some embodiments, the busbar 122, interdigital electrodes 121, and mass block 15 are made of different materials to facilitate configuration according to actual conditions. For example, the interdigital electrodes 121, as the core for excitation and reception of surface acoustic waves, can be made of metal materials with piezoelectric characteristics and excellent conductivity to improve acoustic wave conversion efficiency; the busbar 122 focuses on current collection and transmission, and can be made of materials with high conductivity and low loss to reduce signal attenuation; while the mass block 15 needs to take into account structural support, so it can be made of composite materials with high mechanical strength and low contact resistance.

[0039] In some embodiments, the surface acoustic wave filter 1 further includes a second dielectric layer 16, which is used to fill a plurality of second grooves 112. By filling the plurality of second grooves 112 with the second dielectric layer 16, the surface of the device can be flattened. Specifically, although a mass block 15 is provided in the second groove 112, there may be tiny gaps or height differences between the mass block 15 and the sidewalls and top of the second groove 112. The second dielectric layer 16 can eliminate surface undulations by uniformly filling these gaps, so that the area where the second groove 112 is located forms a continuous and flat whole with the other surfaces of the substrate 11. This flatness not only provides a stable reference surface for subsequent processes and reduces problems such as uneven coating thickness and pattern deviation caused by surface unevenness, but also helps to reduce the scattering loss caused by abrupt changes in surface morphology during sound wave propagation. At the same time, it avoids the accumulation of impurities and moisture in the gaps of the second groove 112, further improving the stability and reliability of the device structure.

[0040] In some embodiments, the second dielectric layer 16 can be fabricated in the same process as the first dielectric layer 14. This simplifies the process flow, reduces repetitive operations in core steps such as photolithography and deposition, shortens the overall device fabrication cycle, and reduces the risk of process deviations such as uneven thickness and compositional differences caused by multiple processes. This is beneficial for improving the consistency and stability of dielectric layer performance during mass production. In addition, the first dielectric layer 14 and the second dielectric layer 16 fabricated in the same process have uniformity in key parameters such as material composition and insulation performance, which can ensure consistent filling effect on the first groove 111 and the second groove 112, avoiding problems such as surface flatness imbalance or uneven insulation performance caused by differences in the characteristics of different dielectric layers.

[0041] In some embodiments, the material of the first dielectric layer 14 may be the same as or different from the material of the second dielectric layer 16. The specific material can be set according to the actual situation, and no specific limitation is made here.

[0042] In some other embodiments, the second dielectric layer 16 may not be provided, and the second groove 112 may be filled with the material of other layers. The specific configuration can be made according to the actual situation, and no specific limitation is made here.

[0043] Please continue reading. Figure 6 , Figure 6 for Figure 1 The diagram shows another structural schematic of the surface acoustic wave filter. In some embodiments, the mass block is located on the upper surface of the interdigital electrode, that is, the mass block 15 is disposed on the side of the interdigital electrode 121 away from the substrate 11. With this arrangement, the sound velocity of the interdigital electrode 121 can be adjusted by the mass block 15 to suppress the propagation of transverse modes, thereby achieving the effect of suppressing transverse stray particles in the band.

[0044] Please continue reading. Figure 7 , Figure 7 for Figure 1 The schematic diagram shown includes a PAD metal layer and a passivation layer in the surface acoustic wave filter. In some embodiments, the surface acoustic wave filter 1 also includes a PAD metal layer 18 and a passivation layer 19. The PAD metal layer 18 is disposed on the side of the busbar 122 away from the substrate 11, and the passivation layer 19 is disposed on the side of the PAD metal layer 18 and the resonator 12 away from the substrate 11.

[0045] Please continue reading. Figure 8 This application also provides a method for manufacturing a surface acoustic wave filter, which includes the following steps: 110. Provide a substrate.

[0046] The substrate 11 can be made of lithium niobate or lithium tantalate.

[0047] 120. A plurality of first grooves are provided on the substrate, and an interconnect layer is provided in each first groove.

[0048] Multiple first grooves 111 are provided on the substrate 11 in the area corresponding to the busbar 122 of the resonator 12, and an interconnect layer 13 is provided in each first groove 111.

[0049] 130. A plurality of resonators are disposed on a substrate, the plurality of resonators including spaced resonators and adjacent resonators, wherein each resonator includes a plurality of interdigital electrodes and a busbar connected to the plurality of interdigital electrodes, and the busbar of the spaced resonator is electrically connected to an interconnect layer in a first groove to make the spaced resonator electrically connected.

[0050] Please continue reading. Figure 9 , Figure 9 for Figure 8 The schematic diagram shown illustrates the process of setting up multiple resonators in the fabrication method. Setting up multiple resonators 12 on the substrate 11 includes the following steps: 131. A first dielectric layer is provided in each first groove.

[0051] A first dielectric layer 14 is provided to cover the interconnect layer 13 within the first groove 111. The first dielectric layer 14 conforms to the sidewall of the groove and the surface of the interconnect layer 13, effectively isolating the interconnect layer 13 from direct physical contact with other areas of the substrate 11. Simultaneously, the filling of the first dielectric layer 14 eliminates voids within the groove, improving the overall density and mechanical strength of the structure, reducing the erosion of the mass block by moisture and impurities in the external environment, and providing a stable working environment for the interconnect layer 13. Furthermore, the surface of the first dielectric layer 14 can be adjusted to be flush with the surface of the substrate 11 or at a preset height, providing a flat reference surface for the subsequent installation of the busbars 122 of the resonator 12. This ensures that the busbars 122 and the interconnect layer 13 achieve precise and reliable electrical connection through the openings, and that adjacent resonator busbars 122 smoothly cross the first dielectric layer 14.

[0052] 132. An opening for exposing the interconnect layer is provided on the first dielectric layer.

[0053] For example, in the overlapping area of ​​the busbar 122 corresponding to the spacer resonator, an opening of a specific size is formed on the first dielectric layer 14 covering the interconnect layer 13 through photolithography, etching, or other processes, exposing the surface of the interconnect layer 13. The opening design retains the overall protection and insulation function of the first dielectric layer 14 for the interconnect layer 13, while the busbar 122 extends into the opening and directly contacts the exposed surface of the interconnect layer 13, so as to realize the electrical connection of the spacer resonator 12 through the mass block.

[0054] Understandably, the size and shape of the opening can be designed according to the width, thickness and connection requirements of the busbar 122 to ensure that the contact area between the busbar 122 and the interconnect layer 13 is sufficient and the position is accurate, so as to avoid the problem of increased resistance or signal transmission interruption due to poor contact, and to maintain the insulation effect of the first dielectric layer 14 on adjacent resonators while ensuring the stability of electrical connection.

[0055] 133. The busbars of the spacer resonator are placed inside the opening so that the busbars of the spacer resonator are electrically connected through the interconnect layer and the adjacent resonators are insulated from each other.

[0056] The busbar 122 of the spacer resonator 12 is placed inside the opening of the first dielectric layer 14. The busbar 122 is in direct contact with the interconnect layer 13. The conductivity of the interconnect layer 13 connects the two independent resonator 12 circuits, forming a stable signal transmission path. This connection method eliminates the need for dielectric layers such as Polyimide / Oxide as bridges. Instead, it uses PAD metal for interconnection, avoiding structural redundancy and signal interference that may result from bridging, and effectively reducing contact resistance and signal transmission loss.

[0057] In some embodiments, the resonator 12 between two spaced-apart resonators 12 is defined as the intermediate resonator 12. After the first dielectric layer 14 is disposed in each first groove 111, the manufacturing method further includes: disposing the busbar 122 of the intermediate resonator 12 on the first dielectric layer 14, without contacting the interconnect layer 13, so that the adjacent resonators 12 are insulated through the first dielectric layer 14, thereby effectively blocking the leakage risk between adjacent resonators 12, while avoiding parasitic capacitance interference caused by the electrode spacing being too close, and ensuring that the adjacent resonators 12 are electrically independent of each other.

[0058] In some embodiments, before setting multiple resonators 12 on the substrate 11, the fabrication method further includes: setting multiple second grooves 112 on the substrate 11, wherein the second grooves 112 and the first grooves 111 do not overlap; and setting a mass block 15 in each second groove 112 to connect the interdigital electrodes 121. For example, a predetermined area for setting the mass block 15 is subsequently set in each interdigital electrode 121. The second groove 112 is formed by etching or other processes, and then the second groove 112 is filled with conductive material to form the mass block 15. This process design of pre-fabricating the second groove 112 and the mass block 15 can match the wiring requirements of the subsequent interdigital electrodes 121, and the electrical connection of the interdigital electrodes 121 at the second groove 112 is achieved through the pre-fabricated mass block 15, ensuring both the flexibility of the interdigital electrode 121 layout and the functionality of the interdigital electrodes 121.

[0059] In some embodiments, the provision of a plurality of first grooves 111 on the substrate 11 and the provision of a plurality of second grooves 112 on the substrate 11 are manufactured in the same process.

[0060] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A surface acoustic wave filter, characterized in that, The surface acoustic wave filter includes: A substrate having a plurality of first grooves, each of which contains an interconnect layer; A plurality of resonators are disposed on the substrate, the plurality of resonators including spaced resonators and adjacent resonators; Each of the resonators includes a plurality of interdigital electrodes and a busbar connected to the plurality of interdigital electrodes. The busbar of the spacer resonator is electrically connected to the interconnect layer in the first groove to make the spacer resonator electrically connected.

2. The surface acoustic wave filter according to claim 1, characterized in that, The first groove is located below the busbar.

3. The surface acoustic wave filter according to claim 2, characterized in that, A first dielectric layer is provided between the busbar and the first groove. At the position corresponding to the first groove, the busbar of the spacer resonator has an opening that exposes the interconnect layer, so that the busbar of the spacer resonator is electrically connected through the interconnect layer, and the adjacent resonators are insulated from each other.

4. The surface acoustic wave filter according to claim 1, characterized in that, A mass block is provided at the end of the interdigital electrode. The mass block is located on the upper surface of the interdigital electrode, or on the side of the interdigital electrode, or on the bottom of the interdigital electrode. When the mass block is located at the bottom of the interdigitated electrode, the substrate is also provided with a second groove, and the mass block is located in the second groove.

5. The surface acoustic wave filter according to claim 4, characterized in that, The first groove and the second groove are made in the same process.

6. The surface acoustic wave filter according to claim 4, characterized in that, The mass block is made of metal or dielectric material. When the mass block is made of metal, the interconnect layer and the mass block are manufactured in the same process.

7. A method for manufacturing a surface acoustic wave filter, characterized in that, The manufacturing method includes: Provide substrate; A plurality of first grooves are formed on the substrate, and an interconnect layer is formed in each first groove; A plurality of resonators are disposed on the substrate, the plurality of resonators including spaced resonators and adjacent resonators, wherein each of the resonators includes a plurality of interdigital electrodes and a busbar connected to the plurality of interdigital electrodes, and the busbar of the spaced resonator is electrically connected to an interconnect layer in the first groove to electrically connect the spaced resonator.

8. The manufacturing method according to claim 7, characterized in that, The plurality of resonators disposed on the substrate include: A first dielectric layer is disposed within each of the first grooves; An opening is provided on the first dielectric layer to expose the interconnect layer; The busbar of the spacer resonator is disposed within the opening so that the busbar of the spacer resonator is electrically connected through the interconnect layer, and the adjacent resonators are insulated from each other.

9. The manufacturing method according to claim 7 or 8, characterized in that, Before placing multiple resonators on the substrate, the fabrication method further includes: A plurality of second grooves are provided on the substrate, wherein the second grooves and the first grooves do not overlap; A mass block is placed in each of the second grooves.

10. The manufacturing method according to claim 9, characterized in that, The plurality of first grooves and the plurality of second grooves on the substrate are formed in the same process.

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