Filter packaging structure and manufacturing method therefor

Abstract

Provided in the present invention is a manufacturing method for a filter packaging structure. The manufacturing method comprises: providing a carrier plate having a roof structure formed on a surface, wherein the roof structure comprises a roof attached to the surface of the carrier plate and a supporting wall located on the roof; providing a substrate having a resonant structure formed on a surface, wherein the resonant structure comprises a resonant body and electrodes located at two sides of the resonant body, and a surface of each electrode comprises a first region close to the resonant body and a second region away from the resonant body; bonding the carrier plate and the substrate, wherein the supporting wall is bonded to the first regions of the electrodes, and the substrate, the supporting wall and the roof enclose a cavity required for operation of the resonant body; removing the carrier plate, such that the second regions of the electrodes are exposed; and forming conductive structures on the second regions of the electrodes. In this way, a cavity forming method in which the cavity is formed by providing the roof on the supporting wall is avoided; therefore, the reliability of the packaging structure is high, and the thickness of the filter packaging structure can also be reduced. Further provided in the present invention is a filter packaging structure.

Description

Filter packaging structure and manufacturing method thereof Technical Field

[0001] The present invention relates to the field of packaging technology, and in particular to a filter packaging structure and a method for manufacturing the filter packaging structure. Background Art

[0002] Surface acoustic wave (SAW) filters are important components in the RF front end. Their working principle is that sound waves are transmitted on the chip surface. The packaging of the SAW filter must prevent the surface of the IDT from contacting other substances to ensure the working space of the IDT.

[0003] Traditional surface acoustic wave filter chips are first packaged using methods such as chip size package (CSP) or wafer level package (WLP) to create a cavity that ensures the operation of the IDT. The packaging structure obtained from the primary packaging is then assembled into a module for secondary packaging. The traditional primary packaging method of surface acoustic wave filters includes: making a supporting wall on the surface of the substrate with the IDT, then affixing a film to the supporting wall to form a film (Roof) to form the cavity required for the IDT to work, and then forming a solder pad on the film and a bump on the solder pad to lead out the electrode on the side of the IDT.

[0004] However, in the aforementioned primary packaging method, when applying the film to the support wall, problems such as uneven coating and poor bonding are easily encountered. Consequently, during the secondary packaging process, due to increased pressure, the cavity in the primary packaging structure is prone to deformation and peeling of the film. In severe cases, the cavity can collapse, thus affecting the operation of the IDT and reducing the reliability of the packaging structure. Furthermore, in the aforementioned primary packaging method, the electrodes are led out by forming pads above the film and bumps on the pads, resulting in a thicker packaging structure. Summary of the Invention

[0005] One of the objectives of the present invention is to provide a filter packaging structure and a manufacturing method thereof, which can reduce the thickness of the filter packaging structure and increase the reliability of the packaging structure.

[0006] In order to achieve the above-mentioned purpose, the present invention provides a method for manufacturing a filter packaging structure on one hand. The method for manufacturing the filter packaging structure includes: providing a carrier with a film structure formed on the surface, the film structure including a film attached to the surface of the carrier and a support wall located on the film; providing a substrate with a resonant structure formed on the surface, the resonant structure including a resonator and electrodes located on both sides of the resonator, the electrode surface including a first area close to the resonator and a second area away from the resonator; bonding the carrier with the film structure formed on the surface and the substrate with the resonant structure formed on the surface, the support wall bonding to the first area of ​​the electrode, the substrate, the support wall and the film enclosing a cavity required for the resonator to work; removing the carrier, exposing the second area of ​​the electrode from the side of the film structure; and forming a conductive structure on the second area of ​​the electrode, the conductive structure protruding from the surface of the film away from the resonant structure.

[0007] Optionally, the method for providing a carrier having a coating structure formed on its surface includes: providing a carrier; forming a first material layer on the surface of the carrier; patterning the first material layer to form the coating; forming a second material layer on the surface of the carrier, the second material layer covering the coating; and patterning the second material layer to form the support wall.

[0008] Optionally, the materials of the covering film and the supporting wall both include photosensitive resist materials; and the patterning process for the first material layer and the patterning process for the second material layer are both performed by exposure and development.

[0009] Optionally, after the first material layer is patterned to form the coating and before the second material layer is formed on the surface of the carrier, a circuit pattern is formed on the coating.

[0010] Optionally, before forming the first material layer on the surface of the carrier, an inorganic material layer is formed on the surface of the carrier, and the inorganic material layer is patterned to form a reinforcement layer; the coating covers the reinforcement layer.

[0011] Optionally, the resonant body is an interdigital transducer; the method for providing a substrate with a resonant structure formed on the surface includes: providing a substrate; forming a metal material layer on the surface of the substrate; and patterning the metal material layer to form an interdigital transducer and an electrode attached to the surface of the substrate.

[0012] Optionally, the method of forming a conductive structure on the second area of ​​the electrode includes: forming a conductive column on the second area of ​​the electrode; and forming a protrusion at one end of the conductive column away from the electrode, the protrusion protruding from the surface of the film away from the resonant structure.

[0013] Another aspect of the present invention provides a filter packaging structure. The filter packaging structure includes a substrate, a resonant structure, a coating structure, and a conductive structure. The resonant structure is formed on the surface of the substrate. The resonant structure includes a resonator and electrodes located on both sides of the resonator. The electrode surface includes a first region close to the resonator and a second region away from the resonator. The coating structure includes a coating and a support wall located on the coating. The support wall is bonded to the first region of the electrode, and the second region of the electrode extends from the side of the coating structure. The substrate, the support wall, and the coating enclose a cavity required for the resonator to work. A conductive structure is provided on the second region of the electrode, and the conductive structure protrudes from the surface of the coating away from the resonant structure.

[0014] Optionally, the resonator is an interdigital transducer; and the electrodes are located on both sides of the interdigital transducer.

[0015] Optionally, the supporting wall surrounds the resonator.

[0016] Optionally, a circuit pattern is formed on a surface of the coating close to the resonator.

[0017] Optionally, the membrane structure further includes a reinforcement layer, and the reinforcement layer is attached to a surface of the membrane away from the resonant structure.

[0018] Optionally, the conductive structure includes a conductive column and a bump; one end of the conductive column is connected to the second region of the electrode, the bump is located at the other end of the conductive column away from the electrode, and the bump protrudes from the surface of the coating away from the resonant structure.

[0019] Optionally, the materials of the support wall and the coating are both photosensitive resist materials.

[0020] In the filter packaging structure and manufacturing method provided by the present invention, a membrane structure can be pre-formed on a carrier board, and the membrane structure and a substrate having a resonant structure formed on its surface are bonded by bonding the support walls of the membrane structure and the electrodes of the resonant structure, thereby forming a cavity required for the operation of the resonator. This avoids the cavity formation method of forming the cavity by coating the membrane on the support walls, avoids the problems of uneven coating and poor bonding strength, and further avoids reliability issues such as easy deformation of the cavity and easy peeling of the coating, thereby improving the reliability of the filter packaging structure. Compared with the solution of using a cover wafer to form the cavity, the process cost is lower, the process control difficulty is reduced, and the thickness of the packaging structure is reduced. In the present invention, the support wall is bonded to the first region of the electrode, and the second region of the electrode extends from the side of the membrane structure, that is, the second region of the electrode is reserved. Therefore, after the membrane structure and the substrate are bonded, a conductive structure can be formed on the second region of the electrode without opening a hole, resulting in a simple process. Compared with the solution of forming solder pads and bumps on the membrane, the conductive structure is directly formed on the second region of the electrode, which facilitates control of the protrusion height of the conductive structure from the membrane surface, thereby facilitating a reduction in the thickness of the filter packaging structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] FIG1 is a flow chart of a method for manufacturing a filter packaging structure provided by an embodiment of the present invention.

[0022] 2 to 10 are schematic structural diagrams of the steps in the manufacturing process of the filter packaging structure provided by an embodiment of the present invention.

[0023] FIG11 is a schematic cross-sectional view of a filter packaging structure provided by an embodiment of the present invention.

[0024] FIG12 is a schematic cross-sectional view of a filter packaging structure provided by another embodiment of the present invention.

[0025] Explanation of the reference numerals: 101 - carrier; 102 - adhesive layer; 103a - first material layer; 103 - coating; 104 - circuit pattern; 105 - support wall; 106 - reinforcement layer; 201 - substrate; 202 - resonator; 203 - electrode; 203a - second region of the electrode; 301 - cavity; 302 - conductive column; 303 - bump. DETAILED DESCRIPTION

[0026] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become more apparent from the following description. It should be noted that the drawings are greatly simplified and not to exact scale, and are only used to facilitate and clearly illustrate the embodiments of the present invention.

[0027] In order to reduce the thickness of a filter packaging structure and improve the reliability of the filter packaging structure, the present invention provides a filter packaging structure and a manufacturing method thereof.

[0028] FIG1 is a flow chart of a method for manufacturing a filter packaging structure according to an embodiment of the present invention. As shown in FIG1 , the method for manufacturing a filter packaging structure according to this embodiment includes:

[0029] Step S1, providing a carrier board having a film structure formed on its surface, wherein the film structure includes a film attached to the surface of the carrier board and a support wall located on the film;

[0030] Step S2, providing a substrate having a resonant structure formed on its surface, wherein the resonant structure includes a resonator and electrodes located on both sides of the resonator, and the electrode surface includes a first area close to the resonator and a second area away from the resonator;

[0031] Step S3, bonding the carrier and the substrate, bonding the support wall to the first region of the electrode, and enclosing a cavity required for the resonator to work by the substrate, the support wall, and the covering film;

[0032] Step S4, removing the carrier board, exposing the second region of the electrode from the side of the coating structure;

[0033] Step S5 : forming a conductive structure on the second region of the electrode, wherein the conductive structure protrudes from the surface of the coating away from the resonant structure.

[0034] It should be understood that although the various steps in the flowchart of FIG1 are shown in sequence as indicated by the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be executed in other orders. Moreover, at least a portion of the steps in FIG1 may include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of steps or stages in other steps.

[0035] Figures 2 through 10 are schematic diagrams illustrating the steps involved in fabricating a filter packaging structure according to an embodiment of the present invention. Figure 11 is a schematic cross-sectional view of a filter packaging structure according to an embodiment of the present invention. The following describes the fabrication method of the filter packaging structure according to this embodiment in conjunction with Figures 1 through 11.

[0036] In step S1 , as shown in FIG. 2 to FIG. 5 , a carrier 101 having a film structure formed on its surface is provided. The film structure includes a film 103 (roof) attached to the surface of the carrier 101 and a supporting wall 105 (wall) located on the film 103 .

[0037] Specifically, as shown in FIG2 , a carrier 101 is provided. The carrier 101 is a rigid carrier, such as a semiconductor wafer or glass plate. An adhesive layer 102 is formed on the surface of the carrier 101 to facilitate attachment of the film structure to the carrier 101 and subsequent separation of the film structure from the carrier 101. In this embodiment, the carrier 101 can be recycled repeatedly, thus helping to save costs.

[0038] For example, when laser debonding is required between the adhesive layer 102 and the carrier 101 and between the adhesive layer 102 and the cover film 103, a light-transmitting carrier, such as a glass plate, should be selected for the carrier 101. The adhesive layer 102 can be formed by lamination, pasting, or spin coating.

[0039] As shown in FIG. 3 , a first material layer 103 a is formed on the surface of the carrier 101 , and the first material layer 103 a covers the carrier 101 and the adhesive layer 102 .

[0040] Exemplarily, the material of the first material layer 103a may include a photoresist material, but is not limited thereto. The photoresist material may be polyimide, benzocyclobutene (BCB), or other polymer materials. The photoresist material may be a dry film; the photoresist material may also be a liquid. The liquid photoresist material may be coated on the carrier 101 and then cured to form the first material layer 103a.

[0041] As shown in FIG4 , the first material layer 103a is patterned to form the coating 103. For example, if the first material layer 103a includes a photoresist, the patterning of the first material layer 103a may include exposing and developing the first material layer 103a. This simplifies the process of forming the coating 103 and ensures high precision in the size and shape of the coating 103. In other embodiments, after forming the first material layer 103a, a patterned mask layer may be formed on the first material layer 103a. The patterned mask layer is then used as a mask to etch the first material layer 103a to form the coating 103.

[0042] As shown in FIG. 4 , in the step of patterning the first material layer 103 a to form the coating 103 , a plurality of coatings 103 may be formed on the carrier 101 .

[0043] After forming the coating 103 on the carrier 101, as shown in Figure 4, a circuit pattern 104 may be formed on the coating 103. The circuit pattern 104 includes but is not limited to an inductor.

[0044] As shown in FIG. 5 , a second material layer is formed on the surface of the carrier 101 , the second material layer covers the coating 103 , and the second material layer is patterned to form support walls 105 .

[0045] Exemplarily, the material of the second material layer may include, but is not limited to, a photoresist material. The photoresist material may be polyimide, benzocyclobutene (BCB), or other polymer materials. The photoresist material may be a dry film; the photoresist material may also be a liquid, which may be coated on the carrier 101 and then cured to form the second material layer.

[0046] Taking the second material layer as an example, where the material includes a photosensitive resist material, patterning the second material layer includes exposing and developing the second material layer. This simplifies the process of forming the support walls 105 and does not require an etching process, thereby preventing etching damage to the cover film 103. In other embodiments, after forming the second material layer, a patterned mask layer may be formed on the second material layer, and the patterned mask layer may then be used as a mask to etch the second material layer to form the support walls 105.

[0047] In this embodiment, the support wall 105 and the covering film 103 are made of the same material, which can avoid the problem of large difference in coefficient of thermal expansion (CTE) caused by different materials between the two, and help improve product reliability.

[0048] As shown in FIG. 5 , the support wall 105 is located outside the circuit pattern 104 , and the thickness of the support wall 105 may be greater than the thickness of the circuit pattern 104 . For example, the support wall 105 may be annular, and the annular support wall 105 may surround the circuit pattern 104 . In this way, the circuit pattern 104 is located in the groove formed by the coating 103 and the support wall 105 , which helps to protect the circuit pattern 104 .

[0049] As shown in FIG. 5 , the outer edge of the support wall 105 is aligned with the edge of the covering film 103 , but the present invention is not limited thereto.

[0050] Step S2 is performed. As shown in FIG6 , a substrate 201 having a resonant structure formed on its surface is provided. The resonant structure includes a resonator 202 and electrodes 203 located on both sides of the resonator 202 . The surface of the electrode 203 includes a first area close to the resonator 202 and a second area away from the resonator 202 .

[0051] In this embodiment, the resonator 202 may be an IDT. Taking the IDT as an example, the method for providing a substrate 201 having a resonant structure formed on its surface may include: providing the substrate 201; forming a metal material layer on the surface of the substrate 201; and patterning the metal material layer to form the IDT and the electrode 203 attached to the surface of the substrate 201.

[0052] In this embodiment, the IDT and the electrode 203 are formed simultaneously in the same process, and the thickness of the IDT can be equal to the thickness of the electrode 203. In other embodiments, depending on performance requirements, the IDT and the electrode 203 can be formed separately in different processes, and the thickness of the IDT and the thickness of the electrode 203 can be different.

[0053] For example, the material of the electrode 203 and the IDT may be copper, nickel palladium gold, nickel gold or aluminum, etc. The thickness of the electrode 203 and the IDT may be 1 μm to 5 μm, but is not limited thereto.

[0054] The substrate 201 may be a piezoelectric substrate, and the material of the piezoelectric substrate may include aluminum nitride (AlN), quartz, lithium niobate, lithium tantalate, or the like.

[0055] 6 , a plurality of resonators 202 may be formed on a substrate 201 , and corresponding electrodes 203 are formed on both sides of each resonator 202 .

[0056] It should be noted that, in this embodiment, step S1 is performed before step S2, but the present invention is not limited thereto. In other embodiments, step S2 may be performed before step S1, or may be performed simultaneously with step S1.

[0057] Execute step S3. Referring to FIG. 7 , the surface of the carrier 101 with the film structure formed thereon is oriented toward the surface of the substrate 201 with the resonant structure formed thereon. The carrier 101 with the film structure formed thereon and the substrate 201 with the resonant structure formed thereon are bonded together. The support wall 105 is bonded to the first region of the electrode 203. The substrate 201, the support wall 105, and the film 103 enclose a cavity 301 required for the operation of the resonator 202. The position of the resonator 202 corresponds to the groove formed by the support wall 105 and the film 103.

[0058] In this embodiment, the carrier 101 and the substrate 201 are bonded together by bonding the support wall 105 to the electrode 203. When the support wall 105 and the electrode 203 are bonded together, the end surface of the support wall 105 is in contact with the first region of the electrode 203, leaving the second region 203a of the electrode free.

[0059] In this embodiment, the carrier 101 and the substrate 201 can be bonded by thermal compression bonding, so that the support wall 105 comprising a photoresist material can adhere to the surface of the electrode 203. In other embodiments, other methods known in the art can be used to bond the carrier 101 having a film structure formed on its surface and the substrate 201 having a resonant structure formed on its surface.

[0060] Execute step S4 , referring to FIG. 7 and FIG. 8 , remove the carrier 101 and the adhesive layer 102 , and expose the second region 203 a of the electrode from the side of the film structure.

[0061] It should be noted that since the carrier 101 and the coating 103 are bonded together by the adhesive layer 102 on the surface of the carrier 101, the carrier 101 and the coating 103 can be easily separated without etching in the step of removing the carrier 101, and the process is relatively simple.

[0062] Step S5 is performed, as shown in FIG9 and FIG10 , to form a conductive structure on the second region 203 a of the electrode, wherein the conductive structure protrudes from the surface of the cover film 103 away from the resonant structure.

[0063] Specifically, the conductive structure may include a conductive column 302 and a bump 303 . One end of the conductive column 302 is connected to the second region of the electrode 203 . The bump 303 is located at the other end of the conductive column 302 and protrudes from the surface of the film 103 away from the resonant structure.

[0064] The method of forming a conductive structure on the second area of ​​the electrode 203 may include: as shown in Figure 9, forming a conductive column 302 on the second area of ​​the electrode 203, the conductive column 302 may be formed by electroplating or other methods, and the conductive column 302 may be increased along the side walls of the support wall 105 and the coating 103; as shown in Figure 10, forming a bump 303 at the end of the conductive column 302 away from the electrode 203, and the bump 303 protrudes from the surface of the coating 103 away from the resonant structure.

[0065] It should be noted that, in this embodiment, referring to Figures 8 and 9, the outer edge of the support wall 105 is aligned with the edge of the coating 103, so that the side walls of the conductive column forming space defined by the side walls of the support wall 105 and the side walls of the coating 103 are straight side walls. In this way, the conductive column 302 formed on the second area of ​​the electrode 203 fills the conductive column forming space with better quality, which is beneficial to improving the stability of the conductive performance of the conductive column 302.

[0066] For example, the end surface of the conductive pillar 302 away from the electrode 203 can be flush with the surface of the film 103 away from the electrode 203, but is not limited thereto. The conductive pillar 302 can be made of a metal material such as copper, nickel, or tin-silver. The bump 303 can be formed by implanting a solder ball on the end surface of the conductive pillar 302 away from the electrode 203 and then performing reflow soldering, but is not limited thereto.

[0067] Next, referring to FIG. 10 and FIG. 11 , the substrate 201 is cut to obtain a plurality of packaged particles.

[0068] In another embodiment of the present application, in step S1, before forming the first material layer 103a on the surface of the carrier 101, an inorganic material layer can be formed on the surface of the carrier 101. The inorganic material layer is then patterned to form a reinforcement layer 106. As shown in FIG12 , the subsequently formed cover film 103 covers the reinforcement layer 106. The provision of the reinforcement layer 106 can increase the compressive strength of the cover film 103 and improve the reliability of the filter packaging structure. Exemplarily, the material of the reinforcement layer 106 can be an inorganic material layer such as silicon oxide (SO2) or silicon nitride (Si3N4).

[0069] This embodiment also provides a filter packaging structure, which can be manufactured using the above-mentioned filter packaging structure manufacturing method. The filter packaging structure can be an uncut packaging structure manufactured using the above-mentioned manufacturing method, or it can be a cut packaging particle.

[0070] As shown in Figure 11, the filter packaging structure includes a substrate 201, a resonant structure, a coating structure, and a conductive structure. The resonant structure is formed on the surface of the substrate 201 and includes a resonator 202 and electrodes 203 located on both sides of the resonator 202. The surface of the electrode 203 includes a first region close to the resonator 202 and a second region away from the resonator 202. The coating structure includes a coating 103 and a support wall 105 located on the coating 103; the support wall 105 is bonded to the first region of the electrode 203, and the second region of the electrode 203 extends from the side of the coating structure. The substrate 201, the support wall 105, and the coating 103 enclose a cavity 301 required for the operation of the resonator 202. A conductive structure is provided on the second region of the electrode 203, which protrudes from the surface of the coating 103 away from the resonant structure.

[0071] For example, the filter packaging structure provided in this embodiment can be a surface acoustic wave filter packaging structure, the resonator 202 can be an interdigital transducer (IDT), and the electrodes 203 can be located on both sides of the IDT. In other embodiments, the filter packaging structure can be other filters that require a cavity to ensure filtering operation, such as a bulk acoustic wave (BAW) filter packaging structure.

[0072] For example, the material of electrode 203 can be copper, nickel-palladium-gold, nickel-gold, or aluminum. The thickness of electrode 203 can be 1 μm to 5 μm. The material of resonator 202 can be the same as that of electrode 203, and the thickness of resonator 202 can also be the same as that of electrode 203, but is not limited thereto. The thickness of resonator 202 can also be different from that of electrode 203.

[0073] 11 , the bonding between the membrane structure and the substrate 201 is achieved by bonding between the support wall 105 and the electrode 203. The support wall 105 may be ring-shaped and surround the resonator 202.

[0074] Exemplarily, the materials of the support wall 105 and the covering film 103 can both be photosensitive resist materials, so that the support wall 105 and the covering film 103 can be formed by exposure and development, which is a relatively simple process and has a high structural precision.

[0075] In this embodiment, the coating structure can be pre-made on the carrier board, and the coating 103 is pasted on the carrier board, and the support wall 105 is stacked on the coating 103. This can avoid the formation of cavities in the coating on the support wall, avoid the problems of uneven coating and poor bonding force, and further avoid reliability problems caused by easy deformation of the cavity and easy peeling of the coating.

[0076] As shown in FIG11 , a circuit pattern 104 is formed on the surface of the cover film 103 near the resonator 202. This circuit pattern 104 can be formed before the cover film structure is bonded to the substrate 201. This allows the integrated circuit pattern 104 to be formed on the inner surface of the cover film 103 near the cavity 301, thereby increasing the integration density of the filter packaging structure and enriching the filter's functionality. Furthermore, the fabrication of the circuit pattern 104 is not limited by the compressive strength of the cavity 301, meaning that the fabrication of the circuit pattern 104 is relatively easy. Furthermore, the cavity 301 can also protect the circuit pattern 104. Exemplarily, the material of the circuit pattern 104 can include copper or aluminum. The circuit pattern 104 includes, but is not limited to, an inductor.

[0077] Illustratively, the conductive structure may include a conductive pillar 302 and a bump 303. One end of the conductive pillar 302 is connected to the second region of the electrode 203, and the bump 303 is located at the other end of the conductive pillar 302, away from the electrode 203. The bump 303 protrudes from the surface of the film 103 away from the resonant structure. The conductive pillar 302 may be made of a metal material such as copper, nickel, or tin-silver. The bump 303 may be made of tin, but is not limited thereto.

[0078] In another embodiment of the present application, as shown in FIG12 , the membrane structure may further include a reinforcement layer 106, which is applied to the surface of the membrane 103 away from the resonant structure. The provision of reinforcement layer 106 can increase the compressive strength of the membrane 103 and improve the reliability of the filter packaging structure. For example, the material of reinforcement layer 106 can be an inorganic material layer such as silicon oxide (SO2) or silicon nitride (Si3N4).

[0079] In the filter packaging structure and manufacturing method provided by the present invention, the coating structure can be formed on the carrier in advance, and the coating structure and the substrate 201 with the resonant structure formed on the surface are bonded by bonding the support wall 105 of the coating structure and the electrode 203 of the resonant structure, and a cavity required for the resonator 202 to work is formed. In this way, the cavity formation method of forming a cavity by coating on the support wall is avoided, and the problems of uneven coating and poor bonding force are avoided, thereby avoiding reliability problems caused by easy deformation of the cavity and easy peeling of the coating, thereby improving the reliability of the filter packaging structure. Compared with the solution of using a cover wafer to make a cavity, the process is simpler and more convenient. The cost is low, the process control is easy, and the thickness of the packaging structure is small. In the present invention, the support wall 105 is bonded to the first area of ​​the electrode 203, and the second area of ​​the electrode 203 extends from the side of the coating structure, that is, the second area of ​​the electrode 203 is reserved, so that after the coating structure and the substrate 201 are bonded, a conductive structure can be made on the second area of ​​the electrode 203 without opening a hole. The process is simple, and compared with the solution of making pads and bumps on the coating, the conductive structure is directly made in the second area of ​​the electrode 203, which is convenient for controlling the protruding height of the conductive structure from the coating surface, which is beneficial to reducing the thickness of the filter packaging structure.

[0080] It should be noted that this specification adopts a progressive description method, and the later description parts focus on the differences from the previous description parts. The same and similar parts between the various parts can be referred to each other.

[0081] The above description is only a description of the preferred embodiment of the present invention, and does not limit the scope of the rights of the present invention. Any person skilled in the art can make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the scope of protection of the technical solution of the present invention.

Claims

1. A manufacturing method of a filter packaging structure, characterized in that Comprising: Providing a carrier plate with a film structure formed on its surface, the film structure including a film adhered to the surface of the carrier plate and a support wall located on the film; Providing a substrate with a resonant structure formed on its surface, the resonant structure including a resonator and electrodes located on both sides of the resonator, and the surface of the electrodes including a first region close to the resonator and a second region far from the resonator; Bonding the carrier plate with the film structure formed on its surface and the substrate with the resonant structure formed on its surface, the support wall being bonded to the first region of the electrodes, and the substrate, the support wall, and the film enclosing a cavity required for the operation of the resonator; Removing the carrier plate, and the second region of the electrodes being exposed from the side of the film structure; And Forming a conductive structure on the second region of the electrodes, the conductive structure protruding from the surface of the film away from the resonant structure.

2. The manufacturing method of the filter package structure according to claim 1, wherein The method for providing a carrier plate with a film structure formed on its surface includes: Providing a carrier plate; Forming a first material layer on the surface of the carrier plate; Performing patterning on the first material layer to form the film; Forming a second material layer on the surface of the carrier plate, the second material layer covering the film; and Performing patterning on the second material layer to form the support wall.

3. The manufacturing method of the filter package structure according to claim 2, characterized in that The materials of both the film and the support wall include photosensitive resist materials; both performing patterning on the first material layer and performing patterning on the second material layer adopt the method of exposure plus development.

4. The manufacturing method of the filter package structure according to claim 2, characterized in that, After performing patterning on the first material layer to form the film and before forming a second material layer on the surface of the carrier plate, forming a circuit pattern on the film.

5. The manufacturing method of the filter package structure according to claim 2, wherein, Before forming a first material layer on the surface of the carrier plate, forming an inorganic material layer on the surface of the carrier plate, performing patterning on the inorganic material layer to form a reinforcement layer; and the film covers above the reinforcement layer.

6. The manufacturing method of the filter package structure according to claim 1, wherein The resonator is an interdigital transducer; The method for providing a substrate with a resonant structure formed on its surface includes: Providing a substrate; Forming a metal material layer on the surface of the substrate; Performing patterning on the metal material layer to form the interdigital transducer and the electrodes adhered to the surface of the substrate.

7. The manufacturing method of the filter package structure according to claim 1, characterized in that The method for forming a conductive structure on the second region of the electrodes includes: Forming conductive pillars on the second region of the electrodes; and Forming bumps at the ends of the conductive pillars far from the electrodes, the bumps protruding from the surface of the film away from the resonant structure.

8. The manufacturing method of the filter package structure according to claim 2, wherein In the step of performing patterning on the first material layer to form the film, multiple films are formed on the carrier plate.

9. The manufacturing method of the filter package structure according to claim 4, characterized in that, The support wall is annular, and the annular support wall surrounds the circuit pattern, and the circuit pattern is located in the groove formed by the film and the support wall.

10. The manufacturing method of the filter package structure according to claim 6, characterized in that, The interdigital transducer and the electrodes are formed simultaneously in the same process, and the thickness of the interdigital transducer is equal to the thickness of the electrodes.

11. A filter packaging structure, characterized in that, Including a substrate, a resonant structure, a film structure, and a conductive structure; The resonant structure is formed on the surface of the substrate. The resonant structure includes a resonator and electrodes located on both sides of the resonator. The surface of the electrodes includes a first region close to the resonator and a second region far from the resonator. The film covering structure includes a film covering and a support wall located on the film covering. The support wall is bonded to the first region of the electrode, and the second region of the electrode extends out from the side of the film covering structure. The substrate, the support wall, and the film covering enclose a cavity required for the operation of the resonator. A conductive structure is provided on the second region of the electrode, and the conductive structure protrudes from the surface of the film covering far from the resonant structure.

12. The filter package structure according to claim 11, wherein The resonator is an interdigital transducer; the electrodes are located on both sides of the interdigital transducer.

13. The filter package structure according to claim 11, wherein The support wall surrounds the resonator.

14. The filter package structure according to claim 11, wherein A circuit pattern is formed on the surface of the film covering close to the resonator.

15. The filter package structure according to claim 11, characterized in that, The film covering structure further includes a reinforcing layer, and the reinforcing layer is attached to the surface of the film covering far from the resonant structure.

16. The filter package structure according to claim 11, wherein, The conductive structure includes a conductive column and a bump; one end of the conductive column is connected to the second region of the electrode, and the bump is located at the other end of the conductive column far from the electrode, and the bump protrudes from the surface of the film covering far from the resonant structure.

17. The filter package structure according to claim 11, wherein The materials of both the support wall and the film covering are photosensitive resist materials.

18. The filter package structure according to claim 11, wherein, Multiple film coverings are formed on the carrier plate.

19. The filter package structure according to claim 14, characterized in that, The support wall is annular, and the annular support wall surrounds the circuit pattern, and the circuit pattern is located in the groove formed by the film covering and the support wall.

20. The filter package structure according to claim 12, wherein The thickness of the interdigital transducer is equal to the thickness of the electrode.

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