Bridge encapsulation method and encapsulation structure

Abstract

The application provides a bridge connection packaging method and a packaging structure. The bridge connection packaging method comprises the following steps: providing a separable substrate with a metal layer; the metal layer is provided with a groove. A first metal column is formed on the metal layer; and a first chip is attached to the groove. The first chip comprises a chip body and an edge layer; the chip body is provided with a first conductive column and a second metal column. The edge layer is beyond the edge of the chip body; the second metal column extends towards the edge layer and does not exceed the edge layer. The edge layer is located in the groove; a first plastic encapsulation body is formed on the separable substrate. The first conductive column and the first metal column are polished to be exposed from the surface of the first plastic encapsulation body. A first wiring layer connected with the first conductive column and the first metal column respectively is formed on the surface of the first plastic encapsulation body. The separable substrate is removed. A second wiring layer connected with the first metal column and the second metal column respectively is formed on the other side of the first plastic encapsulation body. The warping deformation in the packaging process can be improved, and the packaging quality is improved.

Description

Technical Field

[0001] This invention relates to the field of semiconductor packaging technology, and in particular to a bridging packaging method and packaging structure. Background Technology

[0002] With the rapid development of the semiconductor industry, chiplet technology employs a new design approach to package small chips with different functions together, forming a heterogeneous integrated chip packaging structure. Silicon bridge technology achieves electrical connections between chips by embedding small bridge chips with multiple RDLs (redistribution layers) in a substrate, effectively reducing manufacturing costs while maintaining high-density interconnect capabilities. The substrates contain different materials, some organic and some inorganic. Their coefficients of thermal expansion and elastic moduli (Young's modulus) are inconsistent, making them susceptible to thermal stress that can cause delamination of the interface layers, thus affecting product performance. Summary of the Invention

[0003] The purpose of this invention is to provide a bridging packaging method and packaging structure that can effectively improve warpage deformation in the packaging process and improve packaging quality.

[0004] In a first aspect, the present invention provides a bridging packaging method, comprising:

[0005] A separable substrate having a metal layer is provided; wherein the metal layer is provided with grooves;

[0006] A first metal pillar is formed on the metal layer;

[0007] A first chip is mounted in the groove; wherein the first chip includes a chip body and an edge layer, the chip body is provided with a first conductive post and a second metal post; the edge layer is connected to the end of the chip body away from the first conductive post, and the edge layer extends beyond the edge of the chip body; the second metal post extends toward the edge layer but does not extend beyond the edge layer; the edge layer is located in the groove;

[0008] A first molding compound is formed on the separable substrate to encapsulate the first metal pillar and the first chip;

[0009] Grind the first molding compound to expose the end faces of the first conductive post and the first metal post from the surface of the first molding compound;

[0010] A first wiring layer is formed on the surface of the first molding compound, which is respectively connected to the first conductive post and the first metal post;

[0011] Remove the separable substrate;

[0012] A second wiring layer is formed on the side surface of the first encapsulation away from the first wiring layer, which is connected to the first metal pillar and the second metal pillar respectively.

[0013] In an optional implementation, the step of providing a separable substrate with a metal layer includes:

[0014] Provides a separable substrate;

[0015] A bonding adhesive layer is formed on the separable substrate;

[0016] A metal layer is formed on the bonding adhesive layer;

[0017] The groove is formed on the metal layer.

[0018] In an optional embodiment, the step of forming a metal layer on the bonding adhesive layer includes:

[0019] A first metal layer is formed on the bonding adhesive layer;

[0020] A second metal layer is formed on the first metal layer;

[0021] The step of forming the groove on the metal layer includes:

[0022] The groove is formed on the second metal layer; wherein the depth of the groove is equal to the thickness of the second metal layer; or, the depth of the groove is greater than the thickness of the second metal layer and less than or equal to the sum of the thicknesses of the first metal layer and the second metal layer.

[0023] In an optional embodiment, the step of forming the first metal pillar on the metal layer includes:

[0024] Photoresist is formed on the metal layer;

[0025] A first opening is formed in the photoresist, exposing the metal layer; the first opening and the groove are offset from each other.

[0026] The first metal column is formed by filling the first opening with metal.

[0027] In an optional embodiment, the step of forming a second wiring layer on the surface of the first molding compound away from the first wiring layer, which is respectively connected to the first metal post and the second metal post, includes:

[0028] Remove the edge layer and the metal layer so that the side face of the second metal pillar away from the first conductive pillar and the side face of the first metal pillar away from the second wiring layer are exposed from the surface of the first molding compound.

[0029] The second wiring layer is formed on the surface of the first molding compound.

[0030] In an optional embodiment, the step of mounting the first chip in the groove includes:

[0031] Fabricate the first chip;

[0032] Mount the first chip;

[0033] The steps for preparing the first chip include:

[0034] A carrier for mounting a wafer is provided; the wafer is provided with a second metal pillar, the two end faces of the second metal pillar being flush with the two surfaces of the wafer, respectively;

[0035] An edge layer is formed on the surface of the wafer away from the carrier;

[0036] Remove the vehicle;

[0037] A first conductive pillar is formed on the side of the wafer away from the edge layer;

[0038] The wafer is cut to form a first chip with an edge layer.

[0039] In an optional embodiment, the step of forming a first conductive pillar on the side of the wafer away from the edge layer includes:

[0040] An active wiring layer is formed on the side of the wafer away from the edge layer;

[0041] A first conductive pillar is formed on the active wiring layer.

[0042] In an optional implementation, the step of dicing the wafer to form a first chip with an edge layer includes:

[0043] The first cut is made from one side of the first conductive post toward the edge layer to form a partition groove, which exposes the edge layer.

[0044] The second cut involves cutting the bottom of the dividing groove to form a single first chip with an edge layer.

[0045] In an optional implementation, it further includes:

[0046] A first solder ball is formed on the first wiring layer;

[0047] A second solder ball is formed on the second wiring layer;

[0048] A second chip is mounted on the first solder ball or the second solder ball; or, a second chip is mounted on both the first solder ball and the second solder ball.

[0049] In an optional implementation, the edge layer is made of a metallic material.

[0050] The metal material of the edge layer is the same as that of the metal layer; if the metal layer is a single layer, the material of the edge layer is the same as that of the metal layer; if the metal layer is a multi-layer structure, the edge layer is made of titanium or a multi-layer structure; if the edge layer is a multi-layer structure, the surface material of the side of the edge layer away from the second metal pillar is a titanium layer; the materials of the remaining layers are the same as the materials of the metal layers exposed on the sidewall of the groove.

[0051] In a second aspect, the present invention provides a packaging structure manufactured using the bridging packaging method as described in any of the foregoing embodiments; the packaging structure includes:

[0052] A first molding compound, wherein a first metal pillar is disposed within the first molding compound; the first molding compound has a first surface and a second surface disposed opposite to each other; one end of the first metal pillar is flush with the first surface and the other end is flush with the second surface;

[0053] A first chip, wherein the chip is provided with a first conductive post and a second metal post electrically connected; the end face of the first conductive post away from the second metal post is flush with the second surface, and the end face of the second metal post away from the first conductive post is flush with the first surface.

[0054] A first wiring layer is disposed on the second surface and is electrically connected to the first metal pillar and the first conductive pillar, respectively.

[0055] A second wiring layer is disposed on the first surface and electrically connected to the first metal pillar and the second metal pillar, respectively.

[0056] A second chip is mounted on the first wiring layer or the second wiring layer; or, a second chip is mounted on both the first wiring layer and the second wiring layer.

[0057] The second molding compound encapsulates the second chip.

[0058] In an optional embodiment, a third chip is also included; the second molding compound encapsulates the third chip, which is a dummy chip; the third chip is not electrically connected to the first wiring layer or the second wiring layer.

[0059] In an optional embodiment, the first chip further includes an active wiring layer, one side of which is electrically connected to the first conductive pillar and the other side is electrically connected to the second metal pillar.

[0060] In an optional embodiment, a connection pad is provided on the side of the second metal pillar away from the first conductive pillar, and the connection pad is electrically connected to the second wiring layer.

[0061] And / or, the first conductive post has a connection pad on the side away from the second metal post, and the connection pad is electrically connected to the first wiring layer.

[0062] The bridging packaging method and packaging structure provided in this invention have the following advantages:

[0063] The bridging packaging method and structure provided in this invention embed the first chip and the first metal pillar within the first molding compound, resulting in a compact structure that facilitates high-density packaging. The first chip features an edge layer that extends beyond the edge of the chip body. During the thermal process, the edge layer and the metal layer provide support and prevent warping, effectively mitigating warping deformation during packaging, improving packaging quality, and ultimately enhancing product performance. Furthermore, the grooves on the metal layer help position the first chip, improving mounting accuracy. No adhesive layer is needed when mounting the first chip, resulting in higher process efficiency and cost savings. It also eliminates the need for subsequent adhesive layer grinding and avoids the negative impacts associated with such grinding. Attached Figure Description

[0064] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0065] Figure 1 One of the process diagrams for the bridging packaging method provided in the embodiments of the present invention;

[0066] Figure 2 This is another schematic diagram of the formation of the metal layer in the bridging packaging method provided in the embodiment of the present invention;

[0067] Figure 3 This is a second schematic diagram of the manufacturing process of the bridging packaging method provided in an embodiment of the present invention;

[0068] Figure 4 This is a schematic diagram of the structure of the first chip in the bridging packaging method provided in an embodiment of the present invention;

[0069] Figure 5 The third schematic diagram of the manufacturing process of the bridging packaging method provided in the embodiment of the present invention;

[0070] Figure 6Fourth schematic diagram of the manufacturing process of the bridging packaging method provided in the embodiments of the present invention;

[0071] Figure 7 Fifth schematic diagram of the manufacturing process of the bridging packaging method provided in the embodiments of the present invention;

[0072] Figure 8 This is one of the process diagrams for fabricating the first chip provided in an embodiment of the present invention;

[0073] Figure 9 This is a second schematic diagram of the fabrication process for the first chip provided in an embodiment of the present invention;

[0074] Figure 10 A schematic diagram of a packaging structure provided in an embodiment of the present invention;

[0075] Figure 11 Another schematic diagram of the packaging structure provided in the embodiment of the present invention;

[0076] Figure 12 The present invention provides a schematic diagram of a packaging structure including a third chip.

[0077] Icons: 100 - Package structure; 110 - Separable substrate; 111 - Bonding adhesive layer; 112 - Metal layer; 113 - First metal layer; 114 - Second metal layer; 115 - Groove; 116 - Photoresist; 117 - First opening; 118 - First metal pillar; 120 - First chip; 121 - Chip body; 122 - Edge layer; 123 - First conductive pillar; 124 - Second metal pillar; 125 - Active wiring layer; 130 - First molding compound; 141- First dielectric layer; 142- First wiring layer; 143- Second dielectric layer; 144- First solder ball; 151- Second chip; 152- Second colloid; 153- Second molding compound; 154- Third chip; 161- Third dielectric layer; 162- Second wiring layer; 163- Fourth dielectric layer; 164- Second solder ball; 170- Wafer; 171- Carrier; 183- Separator groove; 190- Connecting pad. Detailed Implementation

[0078] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0079] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0080] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0081] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. In addition, the terms "first," "second," "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0082] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0083] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0084] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0085] The bridging packaging method proposed in this invention is beneficial for achieving high-density packaging, mitigating warpage during the packaging process, and improving packaging quality.

[0086] The bridging encapsulation method mainly includes the following steps:

[0087] Please combine Figure 1 S1. Provide a separable substrate 110 having a metal layer 112.

[0088] Optionally, a separable substrate 110 is provided. A bonding adhesive layer 111 is formed on the separable substrate 110. The bonding adhesive layer 111 can be separated from the separable substrate 110 by irradiation with ultraviolet light or by laser debonding.

[0089] A metal layer 112 is formed on the bonding adhesive layer 111. The metal layer 112 can be formed on the surface of the bonding adhesive layer 111 using metal sputtering. The metal layer 112 can be one or more layers, and each metal layer 112 can be a single metal or an alloy. The metal layer 112 serves as a seed layer for subsequent electroplating. In this embodiment, the metal layer 112 includes two layers, such as... Figure 2 First, a first metal layer 113, such as a titanium layer, is formed on the bonding adhesive layer 111. Then, a second metal layer 114, such as a copper layer, is formed on the titanium layer. Using two metal layers serves as a seed layer for electroplating during the subsequent formation of the first metal pillar 118, which improves electroplating efficiency and quality, and enhances the adhesion between the copper layer and the first metal pillar 118. It also improves the structural strength of the separable substrate 110, providing better support. Furthermore, after the separable substrate 110 is removed, the metal layer 112 provides better support for the first molding compound 130, which helps alleviate warpage and improves packaging quality.

[0090] A groove 115 is formed on the metal layer 112. It is understood that the groove 115 may or may not penetrate the metal layer 112; no specific limitation is made here. In this embodiment, the groove 115 is formed on the second metal layer 114; wherein the depth of the groove 115 is equal to the thickness of the second metal layer 114. That is, the groove 115 penetrates the second metal layer 114, the second metal layer 114 is a copper layer, and the first metal layer 113 serves as the bottom of the groove 115. Alternatively, in some embodiments, the groove 115 may also penetrate the first metal layer 113, exposing the bonding adhesive layer 111. Alternatively, the depth of the groove 115 is greater than the thickness of the second metal layer 114 and less than the sum of the thicknesses of the first metal layer 113 and the second metal layer 114. Optionally, the groove 115 can be formed by etching or laser grooving, etc.

[0091] It is understood that if the depth of the groove 115 is the thickness of the second metal layer 114, then the first metal layer 113 (titanium layer) will be exposed after the groove 115 is formed. Titanium has high adhesion and corrosion resistance, as well as a high yield strength of 170 MPa to 485 MPa, providing better support and bonding. Copper has a yield strength of approximately 195 MPa. In this embodiment, the groove 115 is formed by sacrificing a portion of the copper layer, reducing the metal proportion of the copper layer in the entire seed layer, thereby reducing stress and preventing the subsequently formed first metal pillar 118 from breaking at the bottom due to tensile stress from the copper layer. Furthermore, the yield strength of titanium can be used to reduce stress and prevent chemical agents from corroding the bonding adhesive layer 111.

[0092] Please combine Figure 3 S2. A first metal pillar 118 is formed on the metal layer 112.

[0093] Optionally, a photoresist 116 is coated onto the surface of the metal layer 112 using a coating process. A first opening 117 is then formed on the photoresist 116 using an exposure and development method. The first opening 117 penetrates the photoresist 116 and exposes the metal layer 112. That is, the depth of the first opening 117 is equal to the thickness of the photoresist 116. The thickness of the photoresist 116 is designed to determine the height of the first metal pillar 118 to be formed. The position of the first opening 117 should be staggered from the position of the groove 115.

[0094] Then, an electroplating process is used to form a first metal pillar 118 within the first opening 117. In the electroplating process, the metal layer 112 serves as a seed layer, improving electroplating efficiency and quality. After forming the first metal pillar 118, a photoresist 116 is removed using a resist removal process. For example, a resist remover solution can be used to dissolve the photoresist 116, thus achieving its removal.

[0095] Please combine Figure 4 and Figure 5 S3. Mount the first chip 120 in the groove 115.

[0096] The first chip 120 includes a chip body 121 and an edge layer 122. The chip body 121 has a connected first conductive post 123 and a second metal post 124. The first conductive post 123 is located on the end face of the chip body 121 away from the edge layer 122. The edge layer 122 is connected to the end of the chip body 121 away from the first conductive post 123, and the edge layer 122 extends circumferentially beyond the edge of the chip body 121. That is, the cross-section of the edge layer 122 is larger than the cross-section of the chip body 121. The second metal post 124 extends toward the edge layer 122 but does not extend beyond the edge layer 122. The edge layer 122 is located in a groove 115, and the first conductive post 123 faces the side away from the separable substrate 110. Optionally, the depth of the groove 115 is equal to the thickness of the edge layer 122 of the first chip 120.

[0097] In this embodiment, the groove 115 positions the first chip 120, preventing misalignment and improving placement accuracy. Furthermore, there is no need for an adhesive layer to fix the first chip 120; the groove 115 is used for pre-positioning, and then the chip 120 is encapsulated and fixed. By omitting the adhesive layer, the grinding thickness can be reduced in subsequent grinding processes, improving grinding efficiency. It also prevents metal particles from adhering to the adhesive layer and scratching the surface of the first chip 120 during grinding, thus avoiding any impact on grinding accuracy due to the adhesive layer, thereby improving grinding precision.

[0098] S4. A first molding compound 130 is formed on the separable substrate 110, covering the first metal pillar 118 and the first chip 120. The first molding compound 130 is formed using molding processes such as injection molding or stencil printing.

[0099] S5. Grind the first encapsulant 130 so that the end faces of the first conductive post 123 and the first metal post 118 are exposed from the surface of the first encapsulant 130. It can be understood that after grinding, the end faces of the first conductive post 123, the first metal post 118, and the surface of the first encapsulant 130 facing away from the separable substrate 110 are flush.

[0100] S6. A first wiring layer 142 is formed on the surface of the first molding compound 130, which is connected to the first conductive post 123 and the first metal post 118 respectively.

[0101] Optionally, a first dielectric layer 141 is formed on the surface of the first molding compound 130 using a spin coating or spray coating process. The material of the first dielectric layer 141 includes, but is not limited to, polyimide, benzocyclobutene, etc. A photomask with a patterned layer is placed over the first dielectric layer 141. A first patterned opening is formed on the first dielectric layer 141 using an exposure and development process, and metal is filled into the first patterned opening using electroplating, sputtering, or chemical plating to form a first wiring layer 142.

[0102] A second dielectric layer 143 is formed on the first dielectric layer 141 using a spin coating or spray coating process. The material of the second dielectric layer 143 includes, but is not limited to, polyimide, benzocyclobutene, etc. A photomask with a patterned layer is placed over the second dielectric layer 143. A patterned opening is formed on the second dielectric layer 143 using an exposure and development process, exposing the first wiring layer 142. Metal is filled into the patterned opening using electroplating, sputtering, or chemical plating to form a first solder ball 144. Specifically, metal is first electroplated into the patterned opening to form a first bump, which is electrically connected to the first wiring layer 142. Optionally, the first bump is made of copper pillar. Formic acid is used as a reducing agent, and the oxide on the surface of the copper pillar is removed through high temperature and chemical reaction, which is beneficial to promoting the bonding force between the copper pillar and the solder. Then, at least one of titanium, titanium-tungsten, nickel, tin-silver, tin-silver-copper, and tin-bismuth is electroplated on the surface of the first bump to form the first solder ball 144.

[0103] Please combine Figure 6 Optionally, a second chip 151 is mounted, and the second chip 151 is electrically connected to the first solder ball 144. The second chip 151 can be mounted onto the first solder ball 144 using a hot-press mounting process or a flip-chip mounting process. A second adhesive 152 is formed using a dispensing process to protect the solder structure at the first solder ball 144. A second encapsulation body 153 is formed to cover the second chip 151 using a molding process.

[0104] S7. Remove the separable substrate 110.

[0105] Optionally, the bonds can be debonded by irradiating with ultraviolet light, allowing the separable substrate 110 and the first molding compound 130 to separate. It is important to note that after removing the separable substrate 110, the edge layer 122 of the first chip 120 can provide support, preventing stress contraction of the first molding compound 130 and the second molding compound 153 after the removal of the separable substrate 110, thereby preventing warping of the encapsulation structure 100. It should be understood that a high elastic modulus means that the material is not easily elastically deformed under external force. The Young's modulus of the molding compound is relatively low and is greatly affected by temperature changes. For example, the Young's modulus of the molding compound at 25°C is between 3 GPa and 6 GPa. At a curing temperature such as 260°C, the Young's modulus of the molding compound decreases to approximately 1 GPa to 3 GPa, thus making the molding compound prone to deformation and warping. In this embodiment, the design using the edge layer 122 and the metal layer 112 can mitigate the warping deformation of the molding compound and improve the encapsulation quality.

[0106] S8. A second wiring layer 162 is formed on the side surface of the first molding compound 130 away from the first wiring layer 142, which is connected to the first metal post 118 and the second metal post 124 respectively.

[0107] Optionally, the product can be flipped so that the second molding compound 153 faces downwards, providing support. The side of the first molding compound 130 furthest from the first wiring layer 142 faces upwards. The edge layer 122 and the metal layer 112 are removed so that the end face of the second metal post 124 furthest from the first conductive post 123 and the end face of the first metal post 118 furthest from the second wiring layer 162 are exposed on the surface of the first molding compound 130. The edge layer 122 and the metal layer 112 can be removed using a grinding process.

[0108] In this embodiment, since the edge layer 122 and the metal layer 112 have the same thickness, they can be removed simultaneously by grinding. A chemical polishing method can be used. In the chemical polishing process, an polishing solution such as ammonia, hydrofluoric acid, or citric acid is used. Under the pressure of a polishing pad and centrifugal force, the edge layer 122 and the metal layer 112 are polished to expose the surface of the first encapsulant 130 away from the first wiring layer 142. It can be understood that the chemical polishing solution can remove free metal ions from the surface of the first encapsulant 130, thus cleaning the surface.

[0109] Please combine Figure 7 Optionally, a third dielectric layer 161 is formed on the surface of the first molding compound 130, and a second wiring layer 162 is prepared. A fourth dielectric layer 163 and a second solder ball 164 connected to the second wiring layer 162 are formed on the second wiring layer 162. The process method is similar to that described in S6 above, and will not be repeated here.

[0110] Optionally, a second chip 151 is mounted on the second solder ball 164. It should be noted that the second chip 151 may be mounted only on one side of the first solder ball 144, or only on one side of the second solder ball 164. Alternatively, the second chip 151 may be mounted on both the first solder ball 144 and the second solder ball 164. No specific limitation is made here. Finally, the chips are cut and separated into individual products.

[0111] Please combine Figure 8 and Figure 9 Optionally, the step of mounting the first chip 120 in the recess 115 includes: preparing the first chip 120 and mounting the first chip 120. The step of preparing the first chip 120 includes:

[0112] A carrier 171 is provided with a wafer 170 attached thereon; the wafer 170 is provided with a second metal pillar 124, the two end faces of the second metal pillar 124 being flush with the two surfaces of the wafer 170 respectively.

[0113] An edge layer 122 is formed on the surface of wafer 170 away from the carrier 171. It is understood that the edge layer 122 can be formed by sputtering, electroplating, or mounting. The edge layer 122 is made of a metallic material. The metallic material improves support and further mitigates warpage. Furthermore, the metallic material has good thermal conductivity; in the process of separating the separable substrate 110 and the first molding compound 130, the bonding adhesive layer 111 is irradiated with ultraviolet light at a high temperature of 100°C to 300°C. The metallic material improves thermal conductivity, thereby increasing the debonding efficiency of the bonding adhesive layer 111 and preventing bonding adhesive layer 111 residue.

[0114] Optionally, the metal material of the edge layer 122 is the same as that of the metal layer 112 on the separable substrate 110. This improves the structural integrity. Furthermore, the same material results in a consistent coefficient of thermal expansion, mitigating warping caused by thermal stress. Specifically, if the metal layer 112 is a single layer, the material of the edge layer 122 is the same as that of the metal layer 112, for example, both being titanium layers. If the metal layer 112 is a multi-layer structure, the edge layer 122 uses either a titanium layer or a multi-layer structure. If the edge layer 122 is a multi-layer structure, the surface material of the side of the edge layer 122 away from the second metal pillar 124 is a titanium layer; the materials of the remaining layers correspond to the materials of the exposed metal layers 112 on the sidewall of the groove 115. For example, if the metal layer 112 is a two-layer structure of titanium and copper from bottom to top, and the groove 115 is only formed in the copper layer, then the material of the edge layer 122 is selected as a titanium layer. If the groove 115 penetrates both the copper and titanium layers, then the edge layer 122 uses a two-layer structure of copper and titanium layers. Furthermore, after the first chip 120 is mounted, the copper layer of the edge layer 122 and the copper layer in the metal layer 112 are bonded together, and the titanium layer of the edge layer 122 and the titanium layer in the metal layer 112 are bonded together.

[0115] Remove the carrier 171. Optionally, debonding can be achieved by using ultraviolet light irradiation or laser irradiation to separate the wafer 170 and the carrier 171. Flip the wafer 170 so that the edge layer 122 faces downward, providing support. Form a first conductive pillar 123 on the side of the wafer 170 away from the edge layer 122. Optionally, first form an active wiring layer 125 on the side of the wafer 170 away from the edge layer 122; the active wiring layer 125 is electrically connected to the second metal pillar 124. Then form the first conductive pillar 123 on the active wiring layer 125, and the first conductive pillar 123 is electrically connected to the active wiring layer 125. Of course, in some embodiments, the active wiring layer 125 can be omitted, and the first conductive pillar 123 connected to the second metal pillar 124 can be formed directly on the wafer 170.

[0116] A wafer 170 is diced to form a first chip 120 with an edge layer 122. Optionally, in this embodiment, the edge layer 122 is formed by two dicing operations. The first dicing cuts from the side of the first conductive post 123 toward the side of the edge layer 122 to form a partition groove 183, exposing the edge layer 122. The second dicing cuts the bottom of the partition groove 183 to form a single first chip 120 with the edge layer 122. It can be understood that the distance between the dicing line of the second dicing and the wall of the partition groove 183 is the extension width of the edge layer 122 beyond the chip body 121. The wall of the partition groove 183 forms the outer peripheral wall of the chip body 121.

[0117] Please combine Figure 10 This invention also provides a packaging structure 100, manufactured using the bridging packaging method described in any of the foregoing embodiments. The packaging structure 100 includes a first molding compound 130, a first chip 120, a first wiring layer 142, a second wiring layer 162, a second chip 151, and a second molding compound 153. The first molding compound 130 contains a first metal pillar 118; the first molding compound 130 has a first surface and a second surface disposed opposite to each other. One end of the first metal pillar 118 is flush with the first surface, and the other end is flush with the second surface. The first chip 120 has an electrically connected first conductive pillar 123 and a second metal pillar 124; the end face of the first conductive pillar 123 away from the second metal pillar 124 is flush with the second surface, and the end face of the second metal pillar 124 away from the first conductive pillar 123 is flush with the first surface. The first wiring layer 142 is disposed on the second surface and is electrically connected to the first metal pillar 118 and the first conductive pillar 123, respectively. The second wiring layer 162 is disposed on the first surface and is electrically connected to the first metal post 118 and the second metal post 124 respectively.

[0118] Optionally, a first wiring layer 142 is connected to a first solder ball 144, and a second wiring layer 162 is connected to a second solder ball 164. A second chip 151 is mounted on either the first solder ball 144 or the second solder ball 164; alternatively, the first solder ball 144 and the second solder ball 164 are each mounted with a second chip 151. A second molding compound 153 covers the second chip 151. In this embodiment, the second chip 151 is mounted on the first solder ball 144, and a second adhesive 152 is provided at the bottom of the second chip 151 to protect the solder structure at the first solder ball 144.

[0119] Optionally, the first chip 120 further includes an active wiring layer 125, one side of which is electrically connected to the first conductive post 123, and the other side is electrically connected to the second metal post 124. The first chip 120 may be a device such as an inductor, a voltage regulator, a resistor, a capacitor, a transistor, or a diode.

[0120] Please combine Figure 11Optionally, a connection pad 190 is provided on the side of the second metal pillar 124 away from the first conductive pillar 123, and the connection pad 190 is electrically connected to the second wiring layer 162. Alternatively, a connection pad 190 is provided at the end of the first conductive pillar 123 away from the second metal pillar 124, and the connection pad 190 is electrically connected to the first wiring layer 142. Alternatively, the second metal pillar 124 and the first conductive pillar 123 are each connected to a connection pad 190. The connection pad 190 can increase the contact area between the first chip 120 and the wiring layer, improve electrical connection performance, and enhance conductivity.

[0121] In some implementations, one or both sides of the first metal pillar 118 may also be designed with connecting pads 190 to increase the contact area between the first metal pillar 118 and the wiring layer, thereby improving the bonding strength and electrical performance.

[0122] Please combine Figure 12 In some embodiments, the package structure 100 further includes a third chip 154. The third chip 154 ​​is a dummy chip. The dummy chip is also mounted during the mounting of the second chip 151. The dummy chip has no electrical connection to either the first wiring layer 142 or the second wiring layer 162. The second molding compound 153 simultaneously encapsulates both the second chip 151 and the dummy chip. The third chip 154 ​​can be made of any one or more of silicon-based, germanium-based, ceramic, glass, aluminum, and gallium nitride. The dummy chip can improve heat dissipation and support performance, as well as alleviate warpage caused by molding stress.

[0123] In summary, the bridging packaging method and packaging structure 100 provided in the embodiments of the present invention have the following beneficial effects, including:

[0124] The bridging packaging method and packaging structure 100 provided in this embodiment of the invention embed the first chip 120 and the first metal pillar 118 within the first molding compound 130, resulting in a compact structure that facilitates high-density packaging. Furthermore, the first chip 120 has an edge layer 122 that extends beyond the edge of the chip body 121. During the thermal process, the edge layer 122 and the metal layer 112 provide support and prevent warping, effectively reducing warping deformation during the packaging process, improving packaging quality, and ultimately enhancing product performance.

[0125] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; any modifications, equivalent substitutions, improvements, etc., should be included within the protection scope of the present invention.

Claims

1. A bridging packaging method, characterized in that, include: A separable substrate having a metal layer is provided; wherein the metal layer is provided with grooves; A first metal pillar is formed on the metal layer; A first chip is mounted in the groove; wherein the first chip includes a chip body and an edge layer, the chip body is provided with a first conductive post and a second metal post; the edge layer is connected to the end of the chip body away from the first conductive post, and the edge layer extends beyond the edge of the chip body; the second metal post extends toward the edge layer but does not extend beyond the edge layer; the edge layer is located in the groove; A first molding compound is formed on the separable substrate to encapsulate the first metal pillar and the first chip; Grind the first molding compound to expose the end faces of the first conductive post and the first metal post from the surface of the first molding compound; A first wiring layer is formed on the surface of the first molding compound, which is respectively connected to the first conductive post and the first metal post; Remove the separable substrate; A second wiring layer is formed on the side surface of the first encapsulation away from the first wiring layer, which is connected to the first metal pillar and the second metal pillar respectively.

2. The bridging packaging method according to claim 1, characterized in that, The steps of providing a separable substrate with a metal layer include: Provides a separable substrate; A bonding adhesive layer is formed on the separable substrate; A metal layer is formed on the bonding adhesive layer; The groove is formed on the metal layer.

3. The bridging packaging method according to claim 2, characterized in that, The step of forming a metal layer on the bonding adhesive layer includes: A first metal layer is formed on the bonding adhesive layer; A second metal layer is formed on the first metal layer; The step of forming the groove on the metal layer includes: The groove is formed on the second metal layer; wherein the depth of the groove is equal to the thickness of the second metal layer; or, the depth of the groove is greater than the thickness of the second metal layer and less than or equal to the sum of the thicknesses of the first metal layer and the second metal layer.

4. The bridging packaging method according to claim 1, characterized in that, The step of forming the first metal pillar on the metal layer includes: Photoresist is formed on the metal layer; A first opening is formed in the photoresist, exposing the metal layer; the first opening and the groove are staggered. The first metal column is formed by filling the first opening with metal.

5. The bridging packaging method according to claim 1, characterized in that, The step of forming a second wiring layer on the surface of the first molding compound away from the first wiring layer, which is respectively connected to the first metal post and the second metal post, includes: Remove the edge layer and the metal layer so that the side face of the second metal pillar away from the first conductive pillar and the side face of the first metal pillar away from the second wiring layer are exposed from the surface of the first molding compound. The second wiring layer is formed on the surface of the first molding compound.

6. The bridging packaging method according to claim 1, characterized in that, The step of mounting the first chip in the groove includes: Fabricate the first chip; Mount the first chip; The steps for preparing the first chip include: A carrier for mounting a wafer is provided; the wafer is provided with a second metal pillar, the two end faces of the second metal pillar being flush with the two surfaces of the wafer, respectively; An edge layer is formed on the surface of the wafer away from the carrier; Remove the vehicle; A first conductive pillar is formed on the side of the wafer away from the edge layer; The wafer is cut to form a first chip with an edge layer.

7. The bridging packaging method according to claim 6, characterized in that, The step of forming a first conductive pillar on the side of the wafer away from the edge layer includes: An active wiring layer is formed on the side of the wafer away from the edge layer; A first conductive pillar is formed on the active wiring layer.

8. The bridging packaging method according to claim 6, characterized in that, The step of dicing the wafer to form a first chip with an edge layer includes: The first cut is made from one side of the first conductive post toward the edge layer to form a partition groove, which exposes the edge layer. The second cut involves cutting the bottom of the dividing groove to form a single first chip with an edge layer.

9. The bridging packaging method according to any one of claims 1 to 8, characterized in that, Also includes: A first solder ball is formed on the first wiring layer; A second solder ball is formed on the second wiring layer; A second chip is mounted on the first solder ball or the second solder ball; or, a second chip is mounted on both the first solder ball and the second solder ball.

10. The bridging packaging method according to any one of claims 1 to 8, characterized in that, The edge layer is made of metal.

11. The bridging packaging method according to claim 10, characterized in that, The metal material of the edge layer is the same as that of the metal layer; if the metal layer is a single layer, the material of the edge layer is the same as that of the metal layer; if the metal layer is a multi-layer structure, the edge layer is made of titanium or a multi-layer structure; if the edge layer is a multi-layer structure, the surface material of the side of the edge layer away from the second metal pillar is titanium; the materials of the remaining layers and the exposed metal layers on the sidewalls of the groove are the same.

12. A packaging structure, characterized in that, include: A first molding compound, wherein a first metal pillar is disposed within the first molding compound; The first molding compound has a first surface and a second surface disposed opposite to each other; one end of the first metal pillar is flush with the first surface and the other end is flush with the second surface; A first chip, wherein the chip is provided with a first conductive post and a second metal post electrically connected; the end face of the first conductive post away from the second metal post is flush with the second surface, and the end face of the second metal post away from the first conductive post is flush with the first surface. A first wiring layer is disposed on the second surface and is electrically connected to the first metal pillar and the first conductive pillar, respectively. A second wiring layer is disposed on the first surface and electrically connected to the first metal pillar and the second metal pillar, respectively.

13. The packaging structure according to claim 12, characterized in that, The first wiring layer is electrically connected to a first solder ball, and the second wiring layer is electrically connected to a second solder ball; the package structure further includes a second chip, which is mounted on the first solder ball or the second solder ball; or, the first solder ball and the second solder ball are respectively mounted with a second chip; The second molding compound encapsulates the second chip.

14. The packaging structure according to claim 13, characterized in that, It also includes a third chip; the second molding compound encapsulates the third chip, which is a dummy chip; the third chip is not electrically connected to the first wiring layer or the second wiring layer.

15. The packaging structure according to claim 12, characterized in that, The first chip also includes an active wiring layer, one side of which is electrically connected to the first conductive pillar and the other side is electrically connected to the second metal pillar.

16. The packaging structure according to claim 12, characterized in that, The second metal pillar has a connection pad on the side away from the first conductive pillar, and the connection pad is electrically connected to the second wiring layer; And / or, the first conductive post has a connection pad on the side away from the second metal post, and the connection pad is electrically connected to the first wiring layer.

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