Package Structure and Packaging Method of a Resonant Device

Abstract

The present disclosure provides a packaging structure and a packaging method for a resonant device. The packaging structure includes: at least one resonant device, including a first side and a second side opposite to the first side; a sealing portion located on the second side and on at least one resonant device; a packaging substrate located on the sealing portion; the sealing portion is annular, bonding at least one resonant device and the packaging substrate, and there is a cavity between at least one resonant device and the packaging substrate, and the cavity is located inside the sealing portion; a covering layer located on the second side and on at least one resonant device, covering the packaging substrate and the sealing portion, for improving the sealing performance or anti-interference performance. The packaging wafer is bonded to the main wafer through a polymer for wafer-level packaging. Compared with metal bonding, the yield of the product can be improved, and the packaging wafer can use a low-resistance silicon wafer, reducing the packaging cost. In addition, a covering layer is provided outside the packaging wafer for improving the sealing performance of the packaging, and using a metal covering layer can also improve the anti-interference performance.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology. Specifically, the present invention relates to a packaging structure and a packaging method for a resonant device. Background Art

[0002] The radio frequency (RF) front-end chips of wireless communication devices include power amplifiers, antenna switches, RF filters, multiplexers, low-noise amplifiers, etc. Among them, RF filters include piezoelectric surface acoustic wave (SAW) filters, piezoelectric bulk acoustic wave (BAW) filters, micro-electro-mechanical system (MEMS) filters, integrated passive devices (IPD) filters, etc.

[0003] The quality factor values (Q values) of SAW resonators and BAW resonators are relatively high. RF filters with low insertion loss and high out-of-band rejection made from SAW resonators and BAW resonators, namely SAW filters and BAW filters, are the mainstream RF filters used in wireless communication devices such as mobile phones and base stations. Among them, the Q value is the quality factor value of the resonator, defined as the center frequency divided by the 3dB bandwidth of the resonator. The operating frequency of SAW filters is generally from 0.4 GHz to 2.7 GHz, and the operating frequency of BAW filters is generally from 0.7 GHz to 7 GHz.

[0004] The packaging of SAW resonators and BAW resonators can adopt wafer-level chip scale package (WLCSP) technology. WLCSP is a technology that packages and tests the entire main wafer and then cuts it into chips. The size of the packaged chips is almost the same as the size of the wafers on the main wafer. The difference between WLCSP and traditional wafer packaging methods, such as quad flat package (QFP) and ball grid array package (BGA), is that traditional wafer packaging is cut first and then packaged and tested, and the size of the packaged chips increases by about 20% compared to the size of the unpackaged wafers.

[0005] The WLCSP of the resonator metal-bonds the main wafer and the packaging wafer. Among them, the packaging wafer uses a high-resistivity silicon wafer to prevent electrical wire conduction. However, compared with low-resistivity silicon wafers, the cost of high-resistivity silicon wafers is higher; in addition, compared with other connection methods (such as insulating dielectric bonding, polymer bonding, adhesion, etc.), the product yield of metal bonding is lower. Summary of the Invention

[0006] The problem solved by the present invention is to provide a packaging structure and a packaging method for a resonant device, which can improve the product yield, reduce the packaging cost, and at the same time have good sealing performance and anti-interference performance.

[0007] An embodiment of the present invention provides a packaging structure for a resonant device, including: at least one resonant device, the at least one resonant device including a first side and a second side opposite to the first side; a sealing portion located on the second side and on the at least one resonant device; a packaging substrate located on the sealing portion; wherein, the sealing portion is annular, bonding the at least one resonant device and the packaging substrate, and there is a cavity between the at least one resonant device and the packaging substrate, and the cavity is located inside the sealing portion; a covering layer located on the second side and on the at least one resonant device, covering the packaging substrate and the sealing portion, for enhancing the sealing performance or anti-interference performance.

[0008] In some embodiments, the at least one resonant device includes at least one of the following: a bulk acoustic wave resonant device, a surface acoustic wave resonant device.

[0009] In some embodiments, the material of the sealing portion includes a polymer.

[0010] In some embodiments, the material of the packaging substrate includes low-resistance silicon.

[0011] In some embodiments, the material of the covering layer includes: metal, silicon nitride, silicon dioxide.

[0012] In some embodiments, the packaging structure further includes: an electrical wire embedded in and passing through the at least one resonant device, the electrical wire including a first end located on the first side and a second end opposite to the first end located on the second side.

[0013] In some embodiments, the packaging structure further includes: a connection pad located on the second side, between the at least one resonant device and the packaging substrate, connecting the second end, and the connection pad is located inside the sealing portion.

[0014] In some embodiments, the packaging structure further includes: a support portion located between the connection pad and the packaging substrate, bonding the connection pad and the packaging substrate, and the support portion is located inside the sealing portion. In some embodiments, the material of the support portion includes a polymer.

[0015] In some embodiments, the packaging structure further includes: a bump located on the first side, connecting the first end.

[0016] An embodiment of the present invention further provides a packaging method for a resonator device, including: forming a first part, and the forming of the first part includes: providing a plurality of resonator devices, the plurality of resonator devices including a first side and a second side opposite to the first side; forming a second part, and the forming of the second part includes: providing a packaging substrate, the packaging substrate including a third side and a fourth side opposite to the third side; forming a plurality of sealing parts located on the fourth side; bonding the first part and the second part, with the first part located on the fourth side and the second part located on the second side, and the plurality of sealing parts corresponding to the plurality of resonator devices respectively to form a wafer packaging structure; disconnecting the wafer packaging structure to obtain a plurality of chip packaging structures.

[0017] In some embodiments, the material of the packaging substrate includes low-resistance silicon.

[0018] In some embodiments, the material of the plurality of sealing parts includes a polymer. In some embodiments, the plurality of sealing parts are in a ring shape.

[0019] In some embodiments, bonding the first part and the second part includes: bonding the plurality of resonator devices and the packaging substrate through the plurality of sealing parts.

[0020] In some embodiments, disconnecting the wafer packaging structure includes: disconnecting the packaging substrate to obtain a plurality of packaging parts corresponding to the plurality of resonator devices respectively. In some embodiments, disconnecting the wafer packaging structure further includes: after disconnecting the packaging substrate, disconnecting the plurality of resonator devices to obtain the plurality of chip packaging structures.

[0021] In some embodiments, the packaging method further includes: forming a covering layer located on the second side to cover the plurality of packaging parts and the plurality of sealing parts. In some embodiments, the material of the covering layer includes: metal, silicon nitride, silicon dioxide.

[0022] In some embodiments, the forming of the first part further includes: forming a plurality of connection pads located on the second side, and the plurality of connection pads are respectively connected to the active parts of the plurality of resonator devices.

[0023] In some embodiments, the forming of the second part further includes: forming a plurality of support parts located on the fourth side, and at least one of the plurality of support parts is respectively surrounded by the plurality of sealing parts.

[0024] In some embodiments, bonding the first part and the second part includes: bonding the plurality of connection pads and the packaging substrate through the plurality of support parts.

[0025] In some embodiments, the encapsulation method further includes: forming a plurality of electrical leads, embedding and penetrating through the plurality of resonator devices, and respectively connecting the plurality of connection pads. In some embodiments, forming the plurality of electrical leads includes: forming a plurality of through-holes based on the plurality of connection pads, penetrating through the plurality of resonator devices; filling the plurality of through-holes to form the plurality of electrical leads. In some embodiments, the opening size of the plurality of through-holes is smaller than the size of the plurality of support portions.

[0026] It should be noted that bonding the encapsulation wafer to the main wafer through a polymer for wafer-level encapsulation can improve the product yield compared with metal bonding, and the encapsulation wafer can use a low-resistance silicon wafer, reducing the encapsulation cost. In addition, a covering layer is provided outside the encapsulation wafer to enhance the sealing performance of the encapsulation, and using a metal covering layer can also enhance the anti-interference performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a schematic cross-sectional view of structure A of an encapsulation structure of a resonator device according to an embodiment of the present invention;

[0028] Figure 2 is a schematic cross-sectional view of structure B of an encapsulation structure of a resonator device according to an embodiment of the present invention;

[0029] Figure 3 is a schematic flow chart of an encapsulation method 300 of a resonator device according to an embodiment of the present invention;

[0030] Figures 4 to 10 is a schematic cross-sectional view of structure A of an encapsulation method of a resonator device according to an embodiment of the present invention;

[0031] Figures 11 to 17 is a schematic cross-sectional view of structure A of another encapsulation method of a resonator device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following detailed description of the specific embodiments of the present invention is provided in conjunction with the accompanying drawings.

[0033] In the following description, many specific details are set forth to facilitate a thorough understanding of the present invention, but the present invention may be practiced in other ways different from those described herein, so the present invention is not limited by the specific embodiments disclosed below.

[0034] As described in the background art section, the WLCSP of the resonator performs metal bonding on the main wafer and the encapsulation wafer. Among them, the encapsulation wafer uses a high-resistance silicon wafer to prevent the electrical leads from conducting; however, compared with a low-resistance silicon wafer, the cost of the high-resistance silicon wafer is higher; in addition, compared with other connection methods, the product yield of metal bonding is lower.

[0035] The inventors of the present invention have found that bonding the encapsulated wafer to the main wafer through a polymer for wafer-level packaging can improve the product yield compared to metal bonding, and the encapsulated wafer can use a low-resistance silicon wafer, reducing the packaging cost. The inventors of the present invention have also found that a covering layer is provided outside the encapsulated wafer to enhance the sealing of the package, and using a metal covering layer can also enhance the anti-interference performance.

[0036] An embodiment of the present invention provides a packaging structure for a resonant device, including: at least one resonant device, the at least one resonant device including a first side and a second side opposite to the first side; a sealing portion located on the second side and on the at least one resonant device; a packaging substrate located on the sealing portion; wherein, the sealing portion is annular, bonding the at least one resonant device and the packaging substrate, and a cavity is included between the at least one resonant device and the packaging substrate, and the cavity is located inside the sealing portion; a covering layer located on the second side and on the at least one resonant device, covering the packaging substrate and the sealing portion, for enhancing the sealing or anti-interference performance.

[0037] In some embodiments, the at least one resonant device includes at least one of the following: a bulk acoustic wave resonant device, a surface acoustic wave resonant device.

[0038] In some embodiments, the material of the sealing portion includes a polymer.

[0039] In some embodiments, the material of the packaging substrate includes low-resistance silicon.

[0040] In some embodiments, the material of the covering layer includes: metal, silicon nitride, silicon dioxide.

[0041] In some embodiments, the packaging structure further includes: an electrical wire embedded in and passing through the at least one resonant device, the electrical wire including a first end located on the first side and a second end opposite to the first end located on the second side.

[0042] In some embodiments, the packaging structure further includes: a connection pad located on the second side, between the at least one resonant device and the packaging substrate, connecting the second end, and the connection pad is located inside the sealing portion.

[0043] In some embodiments, the packaging structure further includes: a support portion located between the connection pad and the packaging substrate, bonding the connection pad and the packaging substrate, and the support portion is located inside the sealing portion. In some embodiments, the material of the support portion includes a polymer.

[0044] In some embodiments, the packaging structure further includes: a bump located on the first side, connecting the first end.

[0045] It should be noted that, when the encapsulated wafer is bonded to the main wafer through a polymer for wafer-level packaging, compared with metal bonding, the yield of the product can be improved, and the encapsulated wafer can use a low-resistance silicon wafer, reducing the packaging cost.

[0046] In addition, a covering layer is provided on the outer side of the encapsulated wafer to improve the sealing performance of the package, and using a metal covering layer can also improve the anti-interference performance.

[0047] Figure 1 and Figure 2 FIG. shows a specific embodiment of the packaging structure of the present invention. However, the present invention can also be implemented in other ways different from those described herein. Therefore, the present invention is not limited by the specific embodiments disclosed below. It should be noted that the packaging structure of the resonant device provided in the embodiments of the present invention adopts wafer-level packaging technology, and the packaging structures of each chip on the wafer are substantially the same. In order to clearly and intuitively show the packaging structure of the resonant device in the embodiments of the present invention, the following embodiments of the present invention are illustrated based on one chip on the wafer.

[0048] Figure 1 FIG. is a schematic cross-sectional view of structure A of a packaging structure 100 of a resonant device according to an embodiment of the present invention.

[0049] As Figure 1As shown, the packaging structure 100 of the resonant device includes: at least one resonant device 101, where the at least one resonant device 101 includes a first side 101a and a second side 101b opposite to the first side 101a; a plurality of electrical leads 102 embedded in the at least one resonant device 101 and passing through the at least one resonant device 101; a plurality of bumps 103 located on the first side 101a and electrically connecting the first ends of the plurality of electrical leads 102, where the first ends are located on the first side 101a; a plurality of connection pads 104 located on the second side 101b and on the at least one resonant device 101, electrically connecting the second ends of the plurality of electrical leads 102 respectively, where the second ends are located on the second side 101b; a plurality of support portions 105 located on the second side 101b and respectively on the plurality of connection pads 104; a sealing portion 106 located on the second side 101b and on the at least one resonant device 101, with the plurality of support portions 105 located inside the sealing portion 106 (i.e., on the side pointing to the central axis of the resonant device 101); a packaging substrate 107 located on the plurality of support portions 105 and the sealing portion 106, with a cavity between the at least one resonant device 101 and the packaging substrate 107, and the cavity located inside the sealing portion 106; a cover layer 108 located on the second side 101b and above the at least one resonant device 101, covering the sealing portion 106 and the packaging substrate 107.

[0050] In this embodiment, the at least one resonant device 101 includes but is not limited to at least one of the following: BAW resonant device, SAW resonant device.

[0051] In this embodiment, the plurality of connection pads 104 are electrically connected to the active part (not shown) of the at least one resonant device 101.

[0052] In this embodiment, the material of the plurality of support portions 105 includes but is not limited to polymers. In this embodiment, the polymers include but are not limited to at least one of the following: benzocyclobutene (i.e., BCB), photosensitive epoxy resin photoresist (e.g., SU-8), polyimide. It should be noted that the plurality of support portions 105 are used to bond the plurality of connection pads 104 to the packaging substrate 107 and also to resist the plurality of connection pads 104 to prevent them from separating from the at least one resonant device 101.

[0053] In this embodiment, the material of the sealing portion 106 includes, but is not limited to, polymers. In this embodiment, the polymers include, but are not limited to, at least one of the following: benzocyclobutene (i.e., BCB), photo-sensitive epoxy resin photoresist (e.g., SU-8), and polyimide. It should be noted that the sealing portion 106 is used to bond the at least one resonant device 101 to the encapsulation substrate 107 and also to seal the encapsulation structure 100 to form the cavity.

[0054] In this embodiment, the material of the encapsulation substrate 107 includes, but is not limited to, low-resistance silicon.

[0055] In this embodiment, the material of the covering layer 108 includes, but is not limited to, metals, silicon nitride, and silicon dioxide. It should be noted that the covering layer 108 is used to improve the sealing performance of the encapsulation. In addition, using a metal covering layer can improve the anti-interference performance.

[0056] It should be noted that bonding the encapsulation substrate to the resonant device through a polymer for wafer-level encapsulation can improve the product yield compared to metal bonding, and the encapsulation substrate can use a low-resistance silicon substrate, reducing the encapsulation cost.

[0057] Figure 2 It is a schematic cross-sectional view of the structure of section B of an encapsulation structure 100 of a resonant device according to an embodiment of the present invention.

[0058] As Figure 2 shown, in this embodiment, the plurality of connection pads 104 include 4 connection pads, and the plurality of support layers 105 include 4 support portions, corresponding to the 4 connection pads they are connected to respectively. It should be noted that the 4 groups of connection pads and support portions in the embodiment of the present invention are a specific embodiment, and the present invention can also be implemented in other ways different from those described herein. For example, there can be more than 4 groups or less than 4 groups of connection pads and support portions.

[0059] In this embodiment, the sealing portion 106 surrounds the plurality of connection pads 104 and the plurality of support portions 105, and its cross-section B is in a rectangular ring shape. It should be noted that the rectangular ring-shaped sealing portion in the embodiment of the present invention is a specific embodiment, and the present invention can also be implemented using other sealing portions with shapes different from those described herein and known to those skilled in the art (e.g., circular ring shape, polygonal ring shape, etc.).

[0060] In this embodiment, the covering layer 108 surrounds the sealing layer 106, and the shape of the cross-section B of the covering layer 108 corresponds to the shape of the cross-section B of the sealing layer 106, being in a rectangular ring shape.

[0061] Figures 3 to 17Several specific embodiments of the packaging method of the present invention are shown. However, the present invention can also be implemented in other ways different from those described herein. Therefore, the present invention is not limited by the specific embodiments disclosed below. It should be noted that the packaging method of the resonant device provided in the embodiments of the present invention adopts wafer-level packaging technology. The packaging methods of each chip on the wafer are substantially the same. In order to clearly and intuitively show the packaging method of the resonant device in the embodiments of the present invention, the following embodiments of the present invention are illustrated based on two chips on the wafer.

[0062] Figure 3 It is a schematic flow chart of a packaging method 300 of a resonant device according to an embodiment of the present invention.

[0063] As Figure 3 shown, an embodiment of the present invention also provides a packaging method 300 of a resonant device, including:

[0064] Step S301, forming a first part. The forming of the first part includes: providing a plurality of resonant devices, the plurality of resonant devices including a first side and a second side opposite to the first side;

[0065] Step S303, forming a second part. The forming of the second part includes: providing a packaging substrate, the packaging substrate including a third side and a fourth side opposite to the third side; forming a plurality of sealing parts located on the fourth side;

[0066] Step S305, bonding the first part and the second part. The first part is located on the fourth side, the second part is located on the second side, and the plurality of sealing parts respectively correspond to the plurality of resonant devices to form a wafer packaging structure;

[0067] Step S307, disconnecting the wafer packaging structure to obtain a plurality of chip packaging structures.

[0068] In this embodiment, the material of the packaging substrate includes low-resistance silicon.

[0069] In this embodiment, the material of the plurality of sealing parts includes polymer. In this embodiment, the plurality of sealing parts are annular.

[0070] In this embodiment, step S305 includes: bonding the plurality of resonant devices and the packaging substrate through the plurality of sealing parts.

[0071] In this embodiment, step S307 includes: disconnecting the packaging substrate to obtain a plurality of packaging parts respectively corresponding to the plurality of resonant devices. In this embodiment, step S307 further includes: after disconnecting the packaging substrate, disconnecting the plurality of resonant devices to obtain the plurality of chip packaging structures.

[0072] In this embodiment, the encapsulation method 300 further includes: forming a cover layer on the second side to cover the plurality of encapsulation portions and the plurality of sealing portions. In this embodiment, the material of the cover layer includes: metal, silicon nitride, and silicon dioxide.

[0073] In this embodiment, step S301 further includes: forming a plurality of connection pads on the second side, and the plurality of connection pads are respectively connected to the active portions of the plurality of resonator devices.

[0074] In this embodiment, step S303 further includes: forming a plurality of support portions on the fourth side, and at least one of the plurality of support portions is respectively surrounded by the plurality of sealing portions.

[0075] In this embodiment, step S305 further includes: bonding the plurality of connection pads and the encapsulation substrate through the plurality of support portions.

[0076] In this embodiment, the encapsulation method 300 further includes: forming a plurality of electrical wires, embedding and penetrating the plurality of resonator devices, and respectively connecting the plurality of connection pads. In this embodiment, forming the plurality of electrical wires includes: forming a plurality of through holes based on the plurality of connection pads to penetrate the plurality of resonator devices; filling the plurality of through holes to form the plurality of electrical wires. In this embodiment, the opening size of the plurality of through holes is smaller than the size of the plurality of support portions.

[0077] It should be noted that bonding the encapsulation wafer to the main wafer through a polymer for wafer-level encapsulation can improve the product yield compared with metal bonding, and the encapsulation wafer can use a low-resistance silicon wafer, reducing the encapsulation cost.

[0078] In addition, a cover layer is provided outside the encapsulation wafer to improve the sealing performance of the encapsulation, and using a metal cover layer can also improve the anti-interference performance.

[0079] Figures 4 to 10 It is a schematic structural diagram of an encapsulation method for a resonator device according to an embodiment of the present invention.

[0080] As Figure 4 shown, the encapsulation method of the resonator device includes: forming a first portion, and the forming of the first portion includes:

[0081] Providing a plurality of resonator devices 410, the plurality of resonator devices 410 include a first side 410a and a second side 410b opposite to the first side 410a, wherein the plurality of resonator devices 410 include at least one resonator device 411 and at least one resonator device 413;

[0082] Forming a plurality of connection pads 430 on the second side 410b and on the at least one resonator device 411;

[0083] Form a plurality of connection pads 450, located on the second side 410b and on the at least one resonant device 413.

[0084] In this embodiment, the forming of the first part further includes: forming a metal layer (not shown), located on the second side 410b and on the plurality of resonant devices 410, covering the plurality of resonant devices 410.

[0085] In this embodiment, the forming of the plurality of connection pads 430 includes: etching the part of the metal layer corresponding to the at least one resonant device 411 to form the plurality of connection pads 430.

[0086] In this embodiment, the forming of the plurality of connection pads 450 includes: etching the part of the metal layer corresponding to the at least one resonant device 413 to form the plurality of connection pads 450.

[0087] In this embodiment, the plurality of resonant devices 410 include but are not limited to at least one of the following: BAW resonant device, SAW resonant device. In this embodiment, the at least one resonant device 411 includes but is not limited to at least one of the following: BAW resonant device, SAW resonant device. In this embodiment, the at least one resonant device 413 includes but is not limited to at least one of the following: BAW resonant device, SAW resonant device.

[0088] In this embodiment, the plurality of connection pads 430 are electrically connected to the active part (not shown) of the at least one resonant device 411.

[0089] In this embodiment, the plurality of connection pads 450 are electrically connected to the active part (not shown) of the at least one resonant device 413.

[0090] Figure 5 Yes Figure 4 is a top view structural schematic diagram. It should be noted that Figure 5 Illustratively shows 8 connection pads. However, more than 8 connection pads will be formed on a wafer; in this embodiment, for the sake of clearly and intuitively showing the packaging method of the resonant device of the present invention, the illustration is based on 8 connection pads on the wafer.

[0091] In this embodiment, the plurality of connection pads 430 include 4 first connection pads corresponding to the at least one resonant device 411, and the plurality of connection pads 450 include 4 second connection pads corresponding to the at least one resonant device 413.

[0092] As Figure 6 shown, the packaging method of the resonant device further includes: forming a second part, and the forming of the second part includes:

[0093] Provide a packaging substrate 610, the packaging substrate 610 including a third side 610a and a fourth side 610b opposite to the third side 610a;

[0094] Form a plurality of support portions 630, located on the fourth side 610b and on the packaging substrate 610;

[0095] Form a sealing portion 650, located on the fourth side 610b and on the packaging substrate 610, and the plurality of support portions 630 are located between the sealing portions 650;

[0096] Form a plurality of support portions 670, located on the fourth side 610b, on the packaging substrate 610, and outside the sealing portion 650;

[0097] Form a sealing portion 690, located on the fourth side 610b and on the packaging substrate 610, the plurality of support portions 670 are located between the sealing portions 690, and the plurality of support portions 630 are located outside the sealing portion 690.

[0098] In this embodiment, the forming of the second portion further includes: forming a polymer layer (not shown), located on the fourth side 610b and on the packaging substrate 610, covering the packaging substrate 610.

[0099] In this embodiment, the forming of the plurality of support portions 630 includes: etching the polymer layer to form the plurality of support portions 630. In this embodiment, the forming of the sealing portion 650 includes: etching the polymer layer to form the sealing portion 650. In this embodiment, the forming of the plurality of support portions 670 includes: etching the polymer layer to form the plurality of support portions 670. In this embodiment, the forming of the sealing portion 690 includes: etching the polymer layer to form the sealing portion 690.

[0100] In this embodiment, the material of the packaging substrate 610 includes but is not limited to low-resistance silicon.

[0101] In this embodiment, the material of the plurality of support portions 630 includes but is not limited to polymers. In this embodiment, the polymers include but are not limited to at least one of the following: benzocyclobutene (i.e., BCB), photosensitive epoxy resin photoresist (e.g., SU-8), polyimide.

[0102] In this embodiment, the material of the sealing portion 650 includes but is not limited to polymers. In this embodiment, the polymers include but are not limited to at least one of the following: benzocyclobutene (i.e., BCB), photosensitive epoxy resin photoresist (e.g., SU-8), polyimide.

[0103] In this embodiment, the materials of the plurality of support portions 670 include, but are not limited to, polymers. In this embodiment, the polymers include, but are not limited to, at least one of the following: benzocyclobutene (i.e., BCB), photosensitive epoxy resin photoresist (e.g., SU-8), polyimide.

[0104] In this embodiment, the materials of the sealing portion 690 include, but are not limited to, polymers. In this embodiment, the polymers include, but are not limited to, at least one of the following: benzocyclobutene (i.e., BCB), photosensitive epoxy resin photoresist (e.g., SU-8), polyimide.

[0105] Figure 7 is Figure 6 a top view structural schematic diagram. It should be noted that Figure 7 exemplarily shows 8 support portions. However, more than 8 support portions will be formed on a packaged wafer; in this embodiment, for the sake of clearly and intuitively showing the packaging method of the resonant device of the present invention, illustration is made based on 8 support portions on the packaged wafer.

[0106] In this embodiment, the plurality of support portions 630 includes 4 first support portions, and the plurality of support portions 670 includes 4 second support portions.

[0107] In this embodiment, the sealing portion 650 surrounds the plurality of support portions 630, and the sealing portion 690 surrounds the plurality of support portions 670. In this embodiment, the top view surface of the sealing portion 650 is in a rectangular ring shape, and the top view surface of the sealing portion 690 is in a rectangular ring shape. It should be noted that the rectangular ring-shaped sealing portion in the embodiment of the present invention is a specific embodiment, and the present invention can also be implemented by using other sealing portions with shapes different from those known to those skilled in the art described herein (e.g., circular ring shape, polygonal ring shape, etc.).

[0108] As Figure 8 shown, the packaging method of the resonant device further includes: connecting the first portion and the second portion, and connecting the first portion and the second portion includes: bonding the plurality of resonant devices 410 and the packaging substrate 610 through the sealing portion 650 and the sealing portion 690, the packaging substrate 610 being located on the second side 410b, and the plurality of resonant devices 410 being located on the fourth side 610b; bonding the plurality of connection pads 430 and the packaging substrate 610 through the plurality of support portions 630, the plurality of connection pads 430 being located on the fourth side 610b; bonding the plurality of connection pads 450 and the packaging substrate 610 through the plurality of support portions 670, the plurality of connection pads 450 being located on the fourth side 610b.

[0109] In this embodiment, the multiple support portions 630 respectively correspond to the multiple connection pads 430. It should be noted that the multiple support portions 630 are further configured to abut against the multiple connection pads 430 to prevent them from separating from the at least one resonant device 411.

[0110] In this embodiment, the multiple support portions 670 respectively correspond to the multiple connection pads 450. It should be noted that the multiple support portions 670 are further configured to abut against the multiple connection pads 450 to prevent them from separating from the at least one resonant device 413.

[0111] As Figure 9 shown, the encapsulation method of the resonant device further includes:

[0112] Disconnect the encapsulation substrate 610 to form an encapsulation portion 910a for encapsulating the at least one resonant device 411 and an encapsulation portion 910b for encapsulating the at least one resonant device 413;

[0113] Form a covering layer 930 on the second side 410b, on the multiple resonant devices 410, covering the encapsulation portion 910a and the sealing portion 650, and also covering the encapsulation portion 910b and the sealing portion 690.

[0114] In this embodiment, the material of the covering layer 930 includes but is not limited to: metal, silicon nitride, and silicon dioxide.

[0115] As Figure 10 shown, the encapsulation method of the resonant device further includes:

[0116] Form multiple electrical leads 1010, embedded in and penetrating through the at least one resonant device 411. The multiple electrical leads 1010 include a first end located on the first side 410a and a second end located on the second side 410b. The multiple connection pads 430 are electrically connected to the second end;

[0117] Form multiple electrical leads 1030, embedded in and penetrating through the at least one resonant device 413. The multiple electrical leads 1030 include a third end located on the first side 410a and a fourth end located on the second side 410b. The multiple connection pads 450 are electrically connected to the fourth end;

[0118] Form multiple bumps 1050 on the first side 410a, electrically connected to the first end;

[0119] Form multiple bumps 1070 on the first side 410a, electrically connected to the third end;

[0120] Disconnect the multiple resonant devices 410 to obtain an encapsulation structure 1090a and an encapsulation structure 1090b.

[0121] In this embodiment, forming the plurality of electrical conductors 1010 includes: forming a plurality of first through-holes that penetrate the at least one resonant device 411, with the plurality of connection pads 430 respectively located on the plurality of first through-holes, corresponding to the plurality of first through-holes; filling the plurality of first through-holes to form the plurality of electrical conductors 1010.

[0122] In this embodiment, forming the plurality of first through-holes includes: corresponding to the plurality of connection pads 430, etching the at least one resonant device 411 or laser-irradiating the at least one resonant device 411 based on the first side 410a. It should be noted that by laser-irradiating the resonant device within a specific wavelength range, the resonant device can be vaporized and penetrated, thereby forming through-holes more efficiently. After the resonant device is vaporized and penetrated by the laser, the damage to the connection pads located on the resonant device is relatively small, thereby improving the packaging efficiency while ensuring the yield. In this embodiment, the opening size of the plurality of first through-holes (for example, the diameter of the opening on the second side 410b) is smaller than the size of the plurality of support portions 630 (for example, the width of the support portion).

[0123] In this embodiment, forming the plurality of electrical conductors 1030 includes: forming a plurality of second through-holes that penetrate the at least one resonant device 413, with the plurality of connection pads 450 respectively located on the plurality of second through-holes, corresponding to the plurality of second through-holes; filling the plurality of second through-holes to form the plurality of electrical conductors 1030.

[0124] In this embodiment, forming the plurality of second through-holes includes: corresponding to the plurality of connection pads 450, etching the at least one resonant device 413 or laser-irradiating the at least one resonant device 413 based on the first side 410a. It should be noted that by laser-irradiating the resonant device within a specific wavelength range, the resonant device can be vaporized and penetrated, thereby forming through-holes more efficiently. After the resonant device is vaporized and penetrated by the laser, the damage to the connection pads located on the resonant device is relatively small, thereby improving the packaging efficiency while ensuring the yield. In this embodiment, the opening size of the plurality of second through-holes (for example, the diameter of the opening on the second side 410b) is smaller than the size of the plurality of support portions 670 (for example, the width of the support portion).

[0125] In this embodiment, the packaging structure 1090a includes: the at least one resonant device 411, the plurality of electrical conductors 1010, the plurality of bumps 1050, the plurality of connection pads 430, the plurality of support portions 630, the sealing portion 650, and the packaging portion 910a.

[0126] In this embodiment, the encapsulation structure 1090b includes: the at least one resonant device 413, the plurality of electrical conductors 1030, the plurality of bumps 1070, the plurality of connection pads 450, the plurality of support portions 670, the sealing portion 690, and the encapsulation portion 910b.

[0127] It should be noted that the sealing portion 650 is further configured to seal the encapsulation structure 1090a to form a first cavity located between the at least one resonant device 411 and the encapsulation portion 910a; the sealing portion 690 is further configured to seal the encapsulation structure 1090b to form a second cavity located between the at least one resonant device 413 and the encapsulation portion 910b.

[0128] In addition, the covering layer 930 is used to improve the sealing performance of the encapsulation. In addition, using a metal covering layer can improve the anti-interference performance.

[0129] Figures 11 to 17 It is a schematic structural diagram of another encapsulation method for a resonant device according to an embodiment of the present invention.

[0130] As Figure 11 shown, the encapsulation method for the resonant device includes: forming a first part, and the forming of the first part includes:

[0131] Providing a plurality of resonant devices 1110, the plurality of resonant devices 1110 including a first side 1110a and a second side 1110b opposite to the first side 1110a, wherein the plurality of resonant devices 1110 includes at least one resonant device 1111 and at least one resonant device 1113;

[0132] Forming a plurality of connection pads 1130 on the second side 1110b and on the at least one resonant device 1111;

[0133] Forming a plurality of connection pads 1150 on the second side 1110b and on the at least one resonant device 1113.

[0134] In this embodiment, the forming of the first part further includes: forming a metal layer (not shown) on the second side 1110b and on the plurality of resonant devices 1110 to cover the plurality of resonant devices 1110.

[0135] In this embodiment, the forming of the plurality of connection pads 1130 includes: etching the portion of the metal layer corresponding to the at least one resonant device 1111 to form the plurality of connection pads 1130.

[0136] In this embodiment, the forming of the plurality of connection pads 1150 includes: etching the portion of the metal layer corresponding to the at least one resonant device 1113 to form the plurality of connection pads 1150.

[0137] In this embodiment, the multiple resonator devices 1110 include, but are not limited to, at least one of the following: BAW resonator devices, SAW resonator devices. In this embodiment, the at least one resonator device 1111 includes, but is not limited to, at least one of the following: BAW resonator devices, SAW resonator devices. In this embodiment, the at least one resonator device 1113 includes, but is not limited to, at least one of the following: BAW resonator devices, SAW resonator devices.

[0138] In this embodiment, the multiple connection pads 1130 are electrically connected to the active part (not shown) of the at least one resonator device 1111.

[0139] In this embodiment, the multiple connection pads 1150 are electrically connected to the active part (not shown) of the at least one resonator device 1113.

[0140] Figure 12 Yes Figure 11 is a top view structural schematic diagram. It should be noted that Figure 12 Illustratively shows 8 connection pads. However, more than 8 connection pads will be formed on a wafer; for the purpose of clearly and intuitively demonstrating the packaging method of the resonator device in the embodiment of the present invention, the illustration is based on 8 connection pads on the wafer.

[0141] In this embodiment, the multiple connection pads 1130 include 4 first connection pads corresponding to the at least one resonator device 1111, and the multiple connection pads 1150 include 4 second connection pads corresponding to the at least one resonator device 1113.

[0142] Such as Figure 13 shown, the packaging method of the resonator device further includes: forming a second part, and the forming of the second part includes:

[0143] Providing a packaging substrate 1310, the packaging substrate 1310 includes a third side 1310a and a fourth side 1310b opposite to the third side 1310a;

[0144] Forming a plurality of support parts 1330, located on the fourth side 1310b and on the packaging substrate 1310;

[0145] Forming a sealing part 1350, located on the fourth side 1310b and on the packaging substrate 1310, and the plurality of support parts 1330 are located between the sealing parts 1350;

[0146] Forming a plurality of support parts 1370, located on the fourth side 1310b, on the packaging substrate 1310, and outside the sealing part 1350;

[0147] A sealing portion 1390 is formed on the fourth side 1310b of the encapsulation substrate 1310. A plurality of support portions 1370 are located between the sealing portions 1390, and a plurality of support portions 1330 are located outside the sealing portions 1390.

[0148] In this embodiment, the forming of the second portion further includes: forming a polymer layer (not shown) on the fourth side 1310b of the encapsulation substrate 1310 to cover the encapsulation substrate 1310.

[0149] In this embodiment, the forming of the plurality of support portions 1330 includes: etching the polymer layer to form the plurality of support portions 1330. In this embodiment, the forming of the sealing portion 1350 includes: etching the polymer layer to form the sealing portion 1350. In this embodiment, the forming of the plurality of support portions 1370 includes: etching the polymer layer to form the plurality of support portions 1370. In this embodiment, the forming of the sealing portion 1390 includes: etching the polymer layer to form the sealing portion 1390.

[0150] In this embodiment, the material of the encapsulation substrate 1310 includes but is not limited to low-resistance silicon.

[0151] In this embodiment, the material of the plurality of support portions 1330 includes but is not limited to polymer. In this embodiment, the polymer includes but is not limited to at least one of the following: benzocyclobutene (i.e., BCB), photosensitive epoxy resin photoresist (e.g., SU-8), polyimide. In this embodiment, the size of the plurality of support portions 1330 is larger than the size of the plurality of bonding pads 1130.

[0152] In this embodiment, the material of the sealing portion 1350 includes but is not limited to polymer. In this embodiment, the polymer includes but is not limited to at least one of the following: benzocyclobutene (i.e., BCB), photosensitive epoxy resin photoresist (e.g., SU-8), polyimide.

[0153] In this embodiment, the material of the plurality of support portions 1370 includes but is not limited to polymer. In this embodiment, the polymer includes but is not limited to at least one of the following: benzocyclobutene (i.e., BCB), photosensitive epoxy resin photoresist (e.g., SU-8), polyimide. In this embodiment, the size of the plurality of support portions 1370 is larger than the size of the plurality of bonding pads 1150.

[0154] In this embodiment, the material of the sealing portion 1390 includes but is not limited to polymer. In this embodiment, the polymer includes but is not limited to at least one of the following: benzocyclobutene (i.e., BCB), photosensitive epoxy resin photoresist (e.g., SU-8), polyimide.

[0155] Figure 14 is Figure 13 a top view structural schematic diagram of. It should be noted that Figure 14 8 support parts are exemplified, however, more than 8 support parts will be formed on a packaged wafer; for the sake of clearly and intuitively showing the packaging method of the resonant device according to the embodiments of the present invention, the illustration is based on 8 support parts on the packaged wafer.

[0156] In this embodiment, the plurality of support parts 1330 include 4 first support parts, and the plurality of support parts 1370 include 4 second support parts.

[0157] In this embodiment, the sealing part 1350 surrounds the plurality of support parts 1330, and the sealing part 1390 surrounds the plurality of support parts 1370.

[0158] In this embodiment, the top view surface of the sealing part 1350 is in a rectangular ring shape, and the top view surface of the sealing part 1390 is in a rectangular ring shape. It should be noted that the rectangular ring-shaped sealing part in the embodiments of the present invention is a specific embodiment, and the present invention can also be implemented by using other sealing parts with shapes different from those known to those skilled in the art described herein (for example, circular ring shape, polygonal ring shape, etc.).

[0159] As Figure 15 shown, the packaging method of the resonant device further includes: connecting the first part and the second part, and connecting the first part and the second part includes: through the plurality of support parts 1330, the plurality of support parts 1370, the sealing part 1350 and the sealing part 1390, bonding the plurality of resonant devices 1110 to the packaging substrate 1310 to obtain higher bonding strength.

[0160] In this embodiment, the plurality of support parts 1330 correspond to the plurality of connection pads 1130, the plurality of support parts 1330 respectively cover the plurality of connection pads 1130, and bond the plurality of connection pads 1130 to the packaging substrate 1310. It should be noted that the plurality of support parts 1330 are also used to resist the plurality of connection pads 1130 to prevent them from separating from the at least one resonant device 1111.

[0161] In this embodiment, the plurality of support parts 1370 correspond to the plurality of connection pads 1150, the plurality of support parts 1370 respectively cover the plurality of connection pads 1150, and bond the plurality of connection pads 1150 to the packaging substrate 1310. It should be noted that the plurality of support parts 1370 are also used to resist the plurality of connection pads 1150 to prevent them from separating from the at least one resonant device 1113.

[0162] As Figure 16As shown, the packaging method of the resonant device further includes:

[0163] Forming a plurality of electrical leads 1610, embedded in and penetrating through the at least one resonant device 1111, the plurality of electrical leads 1610 including a first end located on the first side 1110a and a second end located on the second side 1110b, and the plurality of connection pads 1130 being electrically connected to the second end;

[0164] Forming a plurality of electrical leads 1630, embedded in and penetrating through the at least one resonant device 1113, the plurality of electrical leads 1630 including a third end located on the first side 1110a and a fourth end located on the second side 1110b, and the plurality of connection pads 1150 being electrically connected to the fourth end;

[0165] Forming a plurality of bumps 1650, located on the first side 1110a, and electrically connecting to the first end;

[0166] Forming a plurality of bumps 1670, located on the first side 1110a, and electrically connecting to the third end.

[0167] In this embodiment, the forming of the plurality of electrical leads 1610 includes: forming a plurality of first through-holes, penetrating through the at least one resonant device 1111, the plurality of connection pads 1130 being respectively located on the plurality of first through-holes, corresponding to the plurality of first through-holes; filling the plurality of first through-holes to form the plurality of electrical leads 1610.

[0168] In this embodiment, the forming of the plurality of first through-holes includes: corresponding to the plurality of connection pads 1130, etching the at least one resonant device 1111 or irradiating the at least one resonant device 1111 with a laser based on the first side 1110a. It should be noted that irradiating the resonant device with a laser within a specific wavelength range can vaporize and penetrate through the resonant device, thereby more efficiently forming through-holes. After the laser vaporizes and penetrates through the resonant device, the damage to the connection pads located on the resonant device is relatively small, thereby improving the packaging efficiency while ensuring the yield.

[0169] In this embodiment, the forming of the plurality of electrical leads 1630 includes: forming a plurality of second through-holes, penetrating through the at least one resonant device 1113, the plurality of connection pads 1150 being respectively located on the plurality of second through-holes, corresponding to the plurality of second through-holes; filling the plurality of second through-holes to form the plurality of electrical leads 1630.

[0170] In this embodiment, forming the plurality of second through-holes includes: corresponding to the plurality of connection pads 1150, etching the at least one resonant device 1113 or irradiating the at least one resonant device 1113 with a laser based on the first side 1110a. It should be noted that irradiating the resonant device with a laser within a specific wavelength range can vaporize through the resonant device, thereby forming through-holes more efficiently. After the laser vaporizes through the resonant device, the damage to the connection pads located on the resonant device is relatively small, thereby improving the packaging efficiency while ensuring the yield.

[0171] As Figure 17 shown, the packaging method of the resonant device further includes:

[0172] Disconnecting the packaging substrate 1310 to form a packaging portion 1710a for packaging the at least one resonant device 1111 and a packaging portion 1710b for packaging the at least one resonant device 1113;

[0173] Forming a covering layer 1730 on the second side 1110b, on the plurality of resonant devices 1110, covering the packaging portion 1710a and the sealing portion 1350, and also covering the packaging portion 1710b and the sealing portion 1390;

[0174] Disconnecting the plurality of resonant devices 1110 to obtain a packaging structure 1750a and a packaging structure 1750b.

[0175] In this embodiment, the material of the covering layer 1730 includes but is not limited to: metal, silicon nitride, and silicon dioxide.

[0176] In this embodiment, the packaging structure 1750a includes: the at least one resonant device 1111, the plurality of electrical leads 1610, the plurality of bumps 1650, the plurality of connection pads 1130, the plurality of support portions 1330, the sealing portion 1350, and the packaging portion 1710a.

[0177] In this embodiment, the packaging structure 1750b includes: the at least one resonant device 1113, the plurality of electrical leads 1630, the plurality of bumps 1670, the plurality of connection pads 1150, the plurality of support portions 1370, the sealing portion 1390, and the packaging portion 1710b.

[0178] It should be noted that the sealing portion 1350 is further used to seal the packaging structure 1750a to form a first cavity between the at least one resonant device 1111 and the packaging portion 1710a; the sealing portion 1390 is further used to seal the packaging structure 1750b to form a second cavity between the at least one resonant device 1113 and the packaging portion 1710b.

[0179] In addition, the cover layer 1730 is used to improve the sealing performance of the package. In addition, using a metal cover layer can improve the anti-interference performance.

[0180] In summary, by bonding the packaged wafer to the main wafer through a polymer for wafer-level packaging, compared with metal bonding, the yield of the product can be improved, and the packaged wafer can use a low-resistance silicon wafer, reducing the packaging cost.

[0181] In addition, a cover layer is provided outside the packaged wafer, which is used to improve the sealing performance of the package. Using a metal cover layer can also improve the anti-interference performance.

[0182] It should be understood that the examples and embodiments herein are merely exemplary, and those skilled in the art can make various modifications and corrections without departing from the spirit and scope of the present invention defined by the present application and the appended claims.

Claims

1. A packaging structure of a resonant device, characterized in that, Comprising: At least one resonant device, the at least one resonant device including a first side and a second side opposite the first side; A sealing portion, located on the second side and on the at least one resonant device; A packaging substrate, located on the sealing portion; Wherein, the sealing portion is annular, bonding the at least one resonant device and the packaging substrate, and a cavity is included between the at least one resonant device and the packaging substrate, and the cavity is located inside the sealing portion; A covering layer, located on the second side and on the at least one resonant device, covering the packaging substrate and the sealing portion, for enhancing the sealing performance or anti-interference performance; An electric wire, embedded in and penetrating through the at least one resonant device, the electric wire including a first end located on the first side and a second end opposite the first end located on the second side; A connection pad, located on the second side, between the at least one resonant device and the packaging substrate, connecting the second end, and the connection pad is located inside the sealing portion; A support portion, located between the connection pad and the packaging substrate, bonding the connection pad and the packaging substrate, the support portion is located inside the sealing portion, wherein the connection pad covers the second end, and the projection of the support portion on the second side covers the second end.

2. The encapsulation structure of the resonant device according to claim 1, characterized in that The at least one resonant device includes at least one of the following: a bulk acoustic wave resonant device, a surface acoustic wave resonant device.

3. The encapsulation structure of the resonant device according to claim 1, characterized in that The material of the sealing portion includes a polymer.

4. The encapsulation structure of the resonant device according to claim 1, characterized in that The material of the packaging substrate includes low-resistance silicon.

5. The encapsulation structure of the resonant device according to claim 1, characterized in that, The material of the covering layer includes: metal, silicon nitride, silicon dioxide.

6. The encapsulation structure of the resonant device according to claim 1, characterized in that, The material of the support portion includes a polymer.

7. The encapsulation structure of the resonant device according to claim 1, characterized in that, Further comprising: A bump, located on the first side and connecting the first end.

8. A packaging method for a resonant device, characterized in that, Comprising: Forming a first part, the forming of the first part includes: providing a plurality of resonant devices, the plurality of resonant devices including a first side and a second side opposite the first side; forming a plurality of connection pads, located on the second side, and the plurality of connection pads respectively connect the active portions of the plurality of resonant devices; Forming a second part, the forming of the second part includes: providing a packaging substrate, the packaging substrate including a third side and a fourth side opposite the third side; forming a plurality of sealing portions, located on the fourth side; forming a plurality of support portions, located on the fourth side, and the plurality of support portions respectively correspond to the plurality of connection pads, and at least one of the plurality of support portions is respectively surrounded by the plurality of sealing portions; Bonding the first part and the second part, the first part is located on the fourth side, the second part is located on the second side, the plurality of sealing portions respectively correspond to the plurality of resonant devices, to form a wafer packaging structure; bonding the first part and the second part includes: bonding the plurality of resonant devices and the packaging substrate through the plurality of sealing portions, and bonding the plurality of connection pads and the packaging substrate through the plurality of support portions; wherein, the connection pad is located between the corresponding resonant device and the packaging substrate, the connection pad is located inside the corresponding sealing portion, and the support portion is located inside the corresponding sealing portion; Form a plurality of electrical conductors, embed and penetrate through the plurality of resonant devices, and respectively connect the plurality of connection pads. The electrical conductors include a first end located on the first side and a second end opposite to the first end located on the second side. The connection pads cover the second end, and the projection of the support portion on the second side covers the second end; Disconnect the wafer package structure to obtain a plurality of chip package structures.

9. The encapsulation method of the resonant device according to claim 8, characterized in that, The material of the package substrate includes low-resistance silicon.

10. The encapsulation method of the resonant device according to claim 8, characterized in that, The materials of the plurality of sealing portions include polymers.

11. The encapsulation method of the resonant device according to claim 8, characterized in that, The plurality of sealing portions are annular.

12. The encapsulation method of the resonant device according to claim 8, characterized in that, Disconnecting the wafer package structure includes: disconnecting the package substrate to obtain a plurality of package portions corresponding to the plurality of resonant devices respectively.

13. The encapsulation method of the resonant device according to claim 12, characterized in that, Disconnecting the wafer package structure further includes: after disconnecting the package substrate, disconnecting the plurality of resonant devices to obtain the plurality of chip package structures.

14. The encapsulation method of the resonant device according to claim 12, characterized in that, Further included: Form a covering layer on the second side to cover the plurality of package portions and the plurality of sealing portions.

15. The encapsulation method of the resonant device according to claim 14, characterized in that, The material of the covering layer includes: metal, silicon nitride, silicon dioxide.

16. The encapsulation method of the resonant device according to claim 8, characterized in that, Forming the plurality of electrical conductors includes: forming a plurality of vias based on the plurality of connection pads to penetrate through the plurality of resonant devices; filling the plurality of vias to form the plurality of electrical conductors.

17. The encapsulation method of the resonant device according to claim 16, characterized in that, The opening size of the plurality of vias is smaller than the size of the plurality of support portions.

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