Filter packaging structure and manufacturing method thereof

Abstract

The invention provides a manufacturing method of a filter packaging structure. The manufacturing method comprises the steps that a carrier plate with a film structure formed on the surface is provided, and the film structure comprises a film attached to the surface of the carrier plate and a supporting wall located on the film; a substrate with a resonance structure formed on the surface is provided, the resonance structure comprises a resonance body and electrodes located on the two sides of the resonance body, and the surface of each electrode comprises a first area close to the resonance body and a second area away from the resonance body; the carrier plate and the substrate are bonded, the supporting wall is bonded with the first area of the electrode, and the substrate, the supporting wall and the covering film define a cavity needed by work of the resonance body; the carrier plate is removed, and the second area of the electrode is exposed; and forming a conductive structure on the second region of the electrode. Therefore, a cavity forming mode of forming a cavity by covering a film on the supporting wall is avoided, the reliability of the packaging structure is high, and the thickness of the filter packaging structure can be reduced. The invention also provides a filter packaging structure.

Description

Technical Field

[0001] The present invention relates to the field of packaging technologies, and particularly relates to a filter packaging structure and a manufacturing method of a filter packaging structure. Background Art

[0002] As an important device in the radio frequency front-end, a surface acoustic wave (SAW) filter works based on the principle that acoustic waves propagate on the chip surface. The packaging of the SAW filter must ensure that the surface of the interdigital transducer does not come into contact with other substances to guarantee the working space of the interdigital transducer.

[0003] For a traditional SAW filter chip, methods such as chip size package (CSP) or wafer level package (WLP) are first used for primary packaging to create a cavity for the interdigital transducer to work. Subsequently, the packaging structure obtained from the primary packaging is assembled into a module for secondary packaging. The traditional primary packaging method for SAW filters includes: fabricating a support wall on the surface of the substrate with interdigital transducers, then laminating a film on the support wall to form a roof to create a cavity required for the interdigital transducer to work. Next, pads and bumps located on the pads are formed above the roof to lead out the electrodes on the side of the interdigital transducer.

[0004] However, in the above primary packaging method, when laminating the film on the support wall, problems such as uneven film lamination and poor bonding force are likely to occur. Furthermore, during the secondary packaging process, due to the increase in pressure, the cavity in the primary packaging structure is prone to deformation, and the film is prone to peeling. In severe cases, the cavity will collapse, thus affecting the operation of the interdigital transducer and resulting in poor reliability of the packaging structure. In addition, in the above primary packaging method, the electrodes are led out by forming pads above the film and forming bumps on the pads, which leads to a relatively large thickness of the packaging structure. Summary of the Invention

[0005] One object of the present invention is to provide a filter packaging structure and its manufacturing method, which can reduce the thickness of the filter packaging structure and have high reliability of the packaging structure.

[0006] To achieve the above object, on the one hand, the present invention provides a method for manufacturing a filter packaging structure. The method for manufacturing the filter packaging structure includes: 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.

[0007] Optionally, 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.

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

[0009] Optionally, 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, a circuit pattern is formed on the film.

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

[0011] Optionally, 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; and performing patterning on the metal material layer to form an interdigital transducer and electrodes adhered to the surface of the substrate.

[0012] Optionally, the method for forming a conductive structure on the second region of the electrodes includes: forming a conductive column on the second region of the electrodes; and forming a bump at the end of the conductive column away from the electrodes, the bump protruding from the surface of the film away from the resonant structure.

[0013] On the other hand, the present invention also provides a filter packaging structure. The filter packaging structure includes a substrate, a resonant structure, a film covering 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, and 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, and 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.

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

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

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

[0017] Optionally, 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.

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

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

[0020] In the filter packaging structure and its manufacturing method provided by the present invention, the film covering structure can be pre-formed on the carrier board, and the film covering structure and the substrate with a resonance structure formed on its surface are bonded by bonding the support wall of the film covering structure and the electrode of the resonance structure, and a cavity required for the operation of the resonator is formed. In this way, the cavity formation method of forming a cavity by covering the film on the support wall is avoided, the problems of uneven film covering and poor bonding force are avoided, and further, the reliability problems caused by easy deformation of the cavity and easy peeling of the film covering are avoided, the reliability of the filter packaging structure is improved, and compared with the solution of using a cover wafer to make a cavity, the process cost is lower, the process control difficulty is smaller, and the thickness of the packaging structure is smaller; in the present invention, 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, that is, the second region of the electrode is reserved, so that a conductive structure can be made on the second region of the electrode without opening a hole after bonding the film covering structure and the substrate. The process is simple, and compared with the solution of making pads and bumps on the film covering, directly making a conductive structure on the second region of the electrode is convenient for controlling the protruding height of the conductive structure protruding from the surface of the film covering, which is beneficial to reducing the thickness of the filter packaging structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 FIG. is a flowchart of a manufacturing method of a filter packaging structure provided by an embodiment of the present invention.

[0022] Figures 2 to 10 FIG. is a schematic diagram of a step-by-step structure during the manufacturing process of a filter packaging structure provided by an embodiment of the present invention.

[0023] Figure 11 FIG. is a cross-sectional schematic diagram of a filter packaging structure provided by an embodiment of the present invention.

[0024] Figure 12 FIG. is a cross-sectional schematic diagram of a filter packaging structure provided by another embodiment of the present invention.

[0025] DESCRIPTION OF REFERENCE NUMERALS: 101 - carrier board; 102 - adhesive layer; 103a - first material layer; 103 - film covering; 104 - circuit pattern; 105 - support wall; 106 - reinforcing layer; 201 - substrate; 202 - resonator; 203 - electrode; 203a - second region of the electrode; 301 - cavity; 302 - conductive column; 303 - bump. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. According to the following description, the advantages and features of the present invention will be clearer. It should be noted that the drawings are all in a very simplified form and use non-precise scales, only for the purpose of conveniently and clearly assisting in explaining the objectives of the embodiments of the present invention.

[0027] In order to reduce the thickness of the 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] Figure 1 It is a flowchart of the manufacturing method of the filter packaging structure provided by an embodiment of the present invention.

[0029] As Figure 1 shown, the manufacturing method of the filter packaging structure provided by this embodiment includes:

[0030] Step S1, 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;

[0031] Step S2, 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;

[0032] Step S3, bonding the carrier plate and the substrate, the support wall being bonded to the first region of the electrode, and the substrate, the support wall and the film enclosing a cavity required for the operation of the resonator;

[0033] Step S4, removing the carrier plate, and the second region of the electrode is exposed from the side of the film structure;

[0034] Step S5, forming a conductive structure on the second region of the electrode, the conductive structure protruding from the surface of the film away from the resonant structure.

[0035] It should be understood that although Figure 1 the steps in the flowchart are shown in sequence according to the indication of the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless there is a clear indication in this article, the execution of these steps has no strict order limit, and these steps can be executed in other orders. Moreover, Figure 1 at least a part of the steps in

[0036] Figures 2 to 10 It is a schematic diagram of the sub-steps during the manufacturing process of the filter packaging structure provided by an embodiment of the present invention. Figure 11 It is a cross-sectional schematic diagram of the filter packaging structure provided by an embodiment of the present invention. The following is combined with Figures 1 to 11Describe the manufacturing method of the filter package structure provided in this embodiment.

[0037] Execute step S1. As Figures 2 to 5 shown, provide a carrier board 101 with a film structure formed on its surface. The film structure includes a film 103 (roof) attached to the surface of the carrier board 101 and a support wall 105 (wall) located on the film 103.

[0038] Specifically, as Figure 2 shown, provide a carrier board 101. The carrier board 101 is a rigid carrier board, such as a semiconductor wafer board or a glass plate, etc. An adhesive layer 102 is formed on the surface of the carrier board 101 to paste the film structure on the carrier board 101 and facilitate the subsequent separation of the film structure from the carrier board 101. In this embodiment, the carrier board 101 can be recycled repeatedly, which helps to save costs.

[0039] Exemplarily, when laser debonding is required for the adhesion between the adhesive layer 102 and the carrier board 101 and the adhesion between the adhesive layer 102 and the film 103, the carrier board 101 should be selected as a transmissive carrier board, such as a glass plate. The adhesive layer 102 can be formed by methods such as pressing, pasting, or spin coating.

[0040] As Figure 3 shown, form a first material layer 103a on the surface of the carrier board 101. The first material layer 103a covers the carrier board 101 and the adhesive layer 102.

[0041] Exemplarily, the material of the first material layer 103a can include photosensitive resist materials, but is not limited thereto. The photosensitive resist material can be polyimide, benzocyclobutene (BCB), or other polymer materials. The photosensitive resist material can be a dry film; the photosensitive resist material can also be liquid, and after the liquid photosensitive resist material is coated on the carrier board 101, it can be cured to form the first material layer 103a.

[0042] As Figure 4 shown, perform patterning on the first material layer 103a to form the film 103. Taking the material of the first material layer 103a including a photosensitive resist material as an example, performing patterning on the first material layer 103a can include exposing and developing the first material layer 103a. In this way, the process of forming the film 103 is relatively simple, and the dimensional shape accuracy of the film 103 is relatively high. In other embodiments, after forming the first material layer 103a, a patterned mask layer can be formed on the first material layer 103a, and then the first material layer 103a is etched using the patterned mask layer as a mask to form the film 103.

[0043] As Figure 4As shown, in the step of patterning the first material layer 103a to form the coating film 103, multiple coating films 103 can be formed on the carrier plate 101.

[0044] After forming the coating film 103 on the carrier plate 101, as Figure 4 shown, a circuit pattern 104 can be formed on the coating film 103. The circuit pattern 104 includes, but is not limited to, an inductor.

[0045] As Figure 5 shown, a second material layer is formed on the surface of the carrier plate 101. The second material layer covers the coating film 103, and the second material layer is patterned to form the support wall 105.

[0046] Exemplarily, the material of the second material layer can include a photosensitive resist material, but is not limited thereto. The photosensitive resist material can be polyimide, benzocyclobutene (BCB), or other polymer materials. The photosensitive resist material can be a dry film; the photosensitive resist material can also be liquid, and after the liquid photosensitive resist material is coated on the carrier plate 101, the second material layer can be formed by curing.

[0047] Taking the material of the second material layer including a photosensitive resist material as an example, patterning the second material layer includes exposing and developing the second material layer. In this way, the process of forming the support wall 105 is relatively simple, and no etching process is required, so that the coating film 103 will not be damaged by etching. In other embodiments, after forming the second material layer, a patterned mask layer can be formed on the second material layer, and then the second material layer is etched using the patterned mask layer as a mask to form the support wall 105.

[0048] In this embodiment, the support wall 105 has the same material as the coating film 103, which can avoid the problem of large differences in the coefficient of thermal expansion (CTE) caused by different materials of the two, and helps to improve the reliability of the product.

[0049] Referring to Figure 5 shown, the support wall 105 is located at the periphery of the circuit pattern 104, and the thickness of the support wall 105 can be greater than the thickness of the circuit pattern 104. For example, the support wall 105 can be annular, and the annular support wall 105 can surround the circuit pattern 104. In this way, the circuit pattern 104 is located in the groove formed by the coating film 103 and the support wall 105, which helps to protect the circuit pattern 104.

[0050] Referring to Figure 5 shown, the outer edge of the support wall 105 is aligned with the edge of the coating film 103, but is not limited thereto.

[0051] Perform step S2, as Figure 6As shown, a substrate 201 with 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 region close to the resonator 202 and a second region far from the resonator 202.

[0052] In this embodiment, the resonator 202 can be an interdigital transducer. Taking the resonator 202 as an interdigital transducer as an example, the method for providing a substrate 201 with a resonant structure formed on its surface can include: providing a substrate 201; forming a metal material layer on the surface of the substrate 201; and performing a patterning process on the metal material layer to form an interdigital transducer and electrodes 203 attached to the surface of the substrate 201.

[0053] In this embodiment, the interdigital transducer and the electrodes 203 are formed simultaneously in the same process, and the thickness of the interdigital transducer and the thickness of the electrodes 203 can be equal. In other embodiments, according to performance requirements, the interdigital transducer and the electrodes 203 can be formed separately in different processes, and the thickness of the interdigital transducer and the thickness of the electrodes 203 can be unequal.

[0054] Exemplarily, the materials of the electrodes 203 and the interdigital transducer can be metal materials such as copper, nickel palladium gold, nickel gold, or aluminum. The thickness of the electrodes 203 and the interdigital transducer can be 1 μm to 5 μm, but is not limited thereto.

[0055] The substrate 201 can be a piezoelectric substrate, and the materials of the piezoelectric substrate can include aluminum nitride (AlN), quartz, lithium niobate, or lithium tantalate, etc.

[0056] Reference Figure 6 As shown, a plurality of resonators 202 can be formed on the substrate 201, and corresponding electrodes 203 are formed on both sides of each resonator 202.

[0057] It should be noted that in this embodiment, step S1 is executed prior to step S2, but is not limited thereto. In other embodiments, step S2 can be executed prior to step S1, or step S2 can be executed simultaneously with step S1.

[0058] Execute step S3. Referring to Figure 7 As shown, the surface of the carrier plate 101 formed with a film structure is oriented towards the surface of the substrate 201 formed with a resonant structure, and the carrier plate 101 with the film structure formed on its surface and the substrate 201 with the resonant structure formed on its surface are bonded. The support wall 105 is bonded to the first region of the electrode 203, and the substrate 201, the support wall 105, and the film 103 enclose a cavity 301 required for the operation of the resonator 202. Among them, the position of the resonator 202 corresponds to the groove constructed by the support wall 105 and the film 103.

[0059] In this embodiment, the bonding between the carrier plate 101 and the substrate 201 is achieved by bonding the support wall 105 and the electrode 203. When the support wall 105 is bonded to the electrode 203, the end face of the support wall 105 fits with the first region of the electrode 203, and the second region 203a of the electrode is left vacant.

[0060] In this embodiment, the carrier plate 101 and the substrate 201 can be bonded by thermocompression bonding, so that the support wall 105 including the photosensitive resist material can be adhered to the surface of the electrode 203. In other embodiments, other methods well known in the art can be used to bond the carrier plate 101 with a film structure formed on its surface and the substrate 201 with a resonant structure formed on its surface.

[0061] Perform step S4. Refer to Figure 7 and Figure 8 As shown, the carrier plate 101 and the adhesive layer 102 are removed, and the second region 203a of the electrode is exposed from the side of the film structure.

[0062] It should be noted that since the carrier plate 101 and the film 103 are bonded through the adhesive layer 102 on the surface of the carrier plate 101, in the step of removing the carrier plate 101, the carrier plate 101 and the film 103 can be easily separated without etching, and the process is relatively simple.

[0063] Perform step S5. As Figure 9 and Figure 10 shown, a conductive structure is formed on the second region 203a of the electrode, and the conductive structure protrudes from the surface of the film 103 away from the resonant structure.

[0064] 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, and 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.

[0065] The method of forming the conductive structure on the second region of the electrode 203 may include: as Figure 9 shown, forming the conductive column 302 on the second region of the electrode 203. The conductive column 302 can be formed by electroplating or the like, and the conductive column 302 can be increased in height along the side walls of the support wall 105 and the film 103; as Figure 10 shown, forming the 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 film 103 away from the resonant structure.

[0066] It should be noted that in this embodiment, refer to Figure 8 and Figure 9As shown, the outer edge of the support wall 105 is aligned with the edge of the film 103, so that the side walls of the conductive column formation space defined by the side walls of the support wall 105 and the film 103 are straight side walls. In this way, the conductive column 302 formed on the second region of the electrode 203 fills the conductive column formation space with better quality, which is beneficial to improving the stability of the electrical conductivity of the conductive column 302.

[0067] Exemplarily, the end face of the conductive column 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 material of the conductive column 302 can include metal materials such as copper, nickel or tin-silver. The bump 303 can be formed by implanting solder balls on the end face of the conductive column 302 away from the electrode 203 and then performing reflow soldering, but is not limited thereto.

[0068] Next, refer to Figure 10 and Figure 11 As shown, the substrate 201 is cut to obtain a plurality of packaged particles.

[0069] In another embodiment of the present application, in step S1, before forming the first material layer 103a on the surface of the carrier plate 101, an inorganic material layer can be formed on the surface of the carrier plate 101, and then the inorganic material layer is patterned to form the reinforcing layer 106, as Figure 12 shown. The subsequently formed film 103 covers the reinforcing layer 106. Setting the reinforcing layer 106 can increase the compressive strength of the film 103 and improve the reliability of the filter packaging structure. Exemplarily, the material of the reinforcing layer 106 can be an inorganic material layer such as silicon dioxide (SO2) or silicon nitride (Si3N4).

[0070] This embodiment also provides a filter packaging structure. The filter packaging structure can be made by using the manufacturing method of the above filter packaging structure. The filter packaging structure can be an uncut packaging structure made by using the above manufacturing method, or a cut packaged particle.

[0071] Refer to Figure 11As shown, the filter package structure includes a substrate 201, a resonant structure, a film structure, and a conductive structure. The resonant structure is formed on the surface of the substrate 201. 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 region close to the resonator 202 and a second region far from the resonator 202. The film structure includes a film 103 and a support wall 105 located on the film 103. The support wall 105 is bonded to the first region of the electrode 203, and the second region of the electrode 203 extends out from the side of the film structure. The substrate 201, the support wall 105, and the film 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, and the conductive structure protrudes from the surface of the film 103 away from the resonant structure.

[0072] Exemplarily, the filter package structure provided in this embodiment can be a surface acoustic wave filter package structure, and the resonator 202 can be an interdigital transducer (IDT). The electrodes 203 can be located on both sides of the interdigital transducer. In other embodiments, the filter package structure can be other filters that require a cavity to ensure filtering operation, such as a bulk acoustic wave (BAW) filter package structure.

[0073] Exemplarily, the material of the electrode 203 can be a metal material such as copper, nickel palladium gold, nickel gold, or aluminum. The thickness of the electrode 203 can be 1 μm to 5 μm. The material of the resonator 202 can be the same as that of the electrode 203, and the thickness of the resonator 202 can also be the same as that of the electrode 203, but it is not limited thereto. The thickness of the resonator 202 can also be different from that of the electrode 203.

[0074] Reference Figure 11 As shown, the bonding of the film structure and the substrate 201 is achieved through the bonding of the support wall 105 and the electrode 203. The support wall 105 can be annular and surround the resonator 202.

[0075] Exemplarily, the materials of both the support wall 105 and the film 103 can be photosensitive resist materials, so that the support wall 105 and the film 103 can be formed by exposure and development. The process is relatively simple, and the accuracy of the structure is relatively high.

[0076] In this embodiment, the film structure can be fabricated on a carrier plate in advance, and the film 103 is pasted on the carrier plate, and the support posts 105 are stacked on the film 103. In this way, it is possible to avoid forming a cavity in the film on the support wall, avoid problems such as uneven film and poor bonding force, and further avoid reliability problems such as easy deformation of the cavity and easy peeling of the film.

[0077] Reference Figure 11 As shown, a circuit pattern 104 is formed on the surface of the film 103 close to the resonator 202. This circuit pattern 104 can be formed before the film structure is bonded to the substrate 201. In this way, the integrated circuit pattern 104 can be formed on the inner surface of the film 103 close to the cavity 301, which can improve the integration density of the filter package structure, enrich the functions of the filter, and the fabrication of the circuit pattern 104 is not limited by the compressive capacity of the cavity 301, that is, the fabrication difficulty of the circuit pattern 104 is relatively small. In addition, 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, inductance.

[0078] Exemplarily, the conductive structure can include conductive posts 302 and bumps 303; one end of the conductive post 302 is connected to the second region of the electrode 203, the bump 303 is located at the other end of the conductive post 302 away from the electrode 203, and the bump 303 protrudes from the surface of the film 103 away from the resonant structure. The material of the conductive post 302 can be a metal material such as copper, nickel, or tin-silver. The material of the bump 303 can be tin, but is not limited thereto.

[0079] In another embodiment of the present application, as Figure 12 shown, the film structure can further include a reinforcing layer 106, and the reinforcing layer 106 is attached to the surface of the film 103 away from the resonant structure. The provision of the reinforcing layer 106 can increase the compressive strength of the film 103 and improve the reliability of the filter package structure. Exemplarily, the material of the reinforcing layer 106 can be an inorganic material layer such as silicon dioxide (SO2) or silicon nitride (Si3N4).

[0080] In the filter packaging structure and its manufacturing method provided by the present invention, the film covering structure can be pre-formed on the carrier board, and the film covering structure and the substrate 201 with a resonance structure formed on its surface are bonded by bonding the support wall 105 of the film covering structure and the electrode 203 of the resonance structure, and a cavity required for the operation of the resonator 202 is formed. In this way, the cavity forming method of forming a cavity by covering a film on the support wall is avoided, the problems of uneven film covering and poor bonding force are avoided, and further the reliability problems caused by easy deformation of the cavity and easy peeling of the film covering are avoided, the reliability of the filter packaging structure is improved, and compared with the solution of using a cover wafer to make a cavity, the process cost is lower, the process control difficulty is smaller, and the thickness of the packaging structure is smaller; in the present invention, the support wall 105 is bonded to the first region of the electrode 203, and the second region of the electrode 203 extends out from the side of the film covering structure, that is, the second region of the electrode 203 is reserved, so that a conductive structure can be made on the second region of the electrode 203 without opening holes after bonding the film covering structure and the substrate 201. The process is simple, and compared with the solution of making pads and bumps on the film covering, directly making a conductive structure on the second region of the electrode 203 is convenient for controlling the protruding height of the conductive structure protruding from the surface of the film covering, which is beneficial to reducing the thickness of the filter packaging structure.

[0081] It should be noted that this specification is described in a progressive manner. The key points described in the subsequent description part are all the differences from the previous description part. For the same and similar parts between each part, reference can be made to each other.

[0082] The above description is only a description of the preferred embodiments of the present invention, and does not limit any 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 decorations made to the above embodiments according to the technical essence of the present invention without departing from the technical solution of the present invention all belong to the protection scope 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 substrate with a film structure formed on its surface, the film structure including a film adhered to the surface of the carrier substrate 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 substrate 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 substrate, 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 substrate with a film structure formed on its surface includes: Providing a carrier substrate; Forming a first material layer on the surface of the carrier substrate; Performing patterning on the first material layer to form the film; Forming a second material layer on the surface of the carrier substrate, 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 the film and the support wall both include photosensitive resist materials; performing patterning on the first material layer and performing patterning on the second material layer both 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 substrate, 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 substrate, forming an inorganic material layer on the surface of the carrier substrate, 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 packaging 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 an interdigital transducer and 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 away from the electrodes, the bumps protruding from the surface of the film away from the resonant structure.

8. 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 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; The film structure includes a film and a support wall located on the film; the support wall is bonded to the first region of the electrodes, the second region of the electrodes extends out from the side of the film structure, and the substrate, the support wall, and the film 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 coating film away from the resonant structure.

9. The filter package structure according to claim 8, characterized in that, The resonator is an interdigital transducer; the electrodes are located on both sides of the interdigital transducer.

10. The filter package structure according to claim 8, wherein The support wall surrounds the resonator.

11. The filter package structure according to claim 8, wherein A circuit pattern is formed on the surface of the coating film close to the resonator.

12. The filter package structure according to claim 8, wherein, The coating film structure further includes a reinforcing layer, and the reinforcing layer is attached to the surface of the coating film away from the resonant structure.

13. The filter package structure according to claim 8, wherein, The conductive structure includes a conductive pillar and a bump; one end of the conductive pillar is connected to the second region of the electrode, the bump is located at the other end of the conductive pillar away from the electrode, and the bump protrudes from the surface of the coating film away from the resonant structure.

14. The filter package structure according to claim 8, characterized in that, The materials of both the support wall and the coating film are photosensitive resist materials.

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