A packaging structure

Abstract

The application discloses a packaging structure. The packaging structure comprises: a plastic layer for covering a wafer to be packaged; a first electroplated metal layer comprising an external pin and a first connecting part connected with each other; the external pin is arranged outside the plastic layer; a first through hole is arranged on one side of the plastic layer where the external pin is arranged; the first connecting part is arranged in the first through hole; the first connecting part is directly connected with the wafer to be packaged in an electric way; or, at least one second electroplated metal layer is further arranged between the first electroplated metal and the wafer to be packaged; the first electroplated metal layer is electrically connected with the wafer to be packaged through the at least one second electroplated metal layer; the first connecting part is directly connected with the second electroplated metal layer closest to the first electroplated metal layer in an electric way; and the second electroplated metal layer closest to the wafer to be packaged is directly connected with the wafer to be packaged in an electric way. The embodiment of the application can improve the production efficiency and the structural stability of the packaging structure.

Description

Technical Field

[0001] This invention relates to the field of packaging technology, and more particularly to a packaging structure. Background Technology

[0002] With the development of technology, power devices, as core components in electrical energy processing and power handling, are being used more and more widely. The main functions of power devices are frequency conversion, voltage transformation, AC power amplification, and power management, playing a crucial role in the normal operation of equipment.

[0003] Existing power device packaging structures require the separate procurement of a carrier and the fabrication of the circuitry. During packaging, copper interconnects are first electroplated onto the chip surface, then tin is applied to the surface of these interconnects. The carrier is then soldered onto the copper interconnects before molding. Current packaging processes require additional fabrication of the circuitry on the carrier, resulting in long lead times, low production efficiency, and multiple steps involved in carrier fabrication. This process is prone to warping, leading to poor bonding between the chip and carrier, delamination, and compromised structural stability of the package. Summary of the Invention

[0004] This invention provides a packaging structure to improve production efficiency and structural stability.

[0005] According to one aspect of the present invention, a packaging structure is provided, comprising: a molding compound, a wafer to be packaged, and a first electroplated metal layer disposed on one side of the wafer to be packaged; the molding compound covers the wafer to be packaged; the first electroplated metal layer includes external pins and a first connecting portion connected to each other; the external pins are disposed outside the molding compound; a first through-hole is disposed on the side of the molding compound on which the external pins are disposed, and the first connecting portion is disposed within the first through-hole.

[0006] The first connecting portion is in direct electrical contact with the wafer to be packaged; or, at least one second electroplated metal layer is provided between the first electroplated metal and the wafer to be packaged, the molding compound covers the at least one second electroplated metal layer, the first electroplated metal layer is electrically connected to the wafer to be packaged through the at least one second electroplated metal layer, the first connecting portion is in direct electrical contact with the second electroplated metal layer closest to the first electroplated metal layer, and the second electroplated metal layer closest to the wafer to be packaged is in direct electrical contact with the wafer to be packaged.

[0007] Optionally, each of the second electroplated metal layers includes a planar portion and a second connecting portion that are interconnected; the second connecting portion of each of the second electroplated metal layers is disposed on the side of the planar portion of the second electroplated metal layer adjacent to the wafer to be packaged.

[0008] The second connection portion is in direct electrical contact with the wafer to be packaged, or the second connection portion is in direct electrical contact with a planar portion of another second electroplated metal layer located on the side adjacent to the wafer to be packaged.

[0009] Optionally, a groove is provided on a preset edge area of ​​the first surface of the molding compound where the external pin is located. The preset edge area is adjacent to the external pin, and the groove penetrates the second surface of the molding compound. The second surface of the molding compound surrounds the first surface of the molding compound and is connected to the first surface. The groove is used to provide a conductive material so that the external pin is connected to an external circuit through the conductive material.

[0010] Optionally, a connecting layer is provided in the trench, the connecting layer covering the trench and extending from the trench to the external pin; the connecting layer is used to improve the adhesion between the conductive material and the molding layer.

[0011] Optionally, the external pins include a first external pin, a second external pin, and a third external pin; the first external pin includes a first body portion and at least two first interdigitated portions connected to the first body portion, the second external pin includes a second body portion and at least two second interdigitated portions connected to the second body portion, the first body portion and the second body portion extend along a first direction, the first interdigitated portions and the second interdigitated portions extend along a second direction and are located between the first body portion and the second body portion.

[0012] Along the first direction, the first insertion finger and the second insertion finger are arranged alternately in sequence, and the third external pin is located between the edge of the first main body and a second insertion finger; wherein the first direction and the second direction intersect each other.

[0013] Optionally, the packaging structure further includes: a heat sink; the heat sink is disposed on the side of the wafer to be packaged away from the external pins, the molding compound covers the heat sink, and a portion of the heat sink away from the surface of the wafer to be packaged exposes the molding compound.

[0014] Optionally, the diameter of the first through hole is greater than or equal to 100 micrometers; the material of the encapsulation layer includes resin.

[0015] According to another aspect of the present invention, a method for preparing an encapsulation structure is provided, comprising:

[0016] Provide wafers to be packaged.

[0017] A first electroplated metal layer and a molding compound layer are prepared on the surface of the wafer to be packaged; or, a first electroplated metal layer, at least one second electroplated metal layer, and a molding compound layer are prepared on the surface of the wafer to be packaged; wherein the molding compound layer covers the wafer to be packaged; the first electroplated metal layer includes interconnected external leads and a first connection portion; the external leads are disposed outside the molding compound layer; a first through-hole is provided on the side of the molding compound layer where the external leads are disposed, and the first connection portion is disposed in the first through-hole.

[0018] Preparing a first electroplated metal layer and a molding compound layer on the surface of a wafer to be packaged includes: the first connecting portion being in direct contact with and electrically connected to the wafer to be packaged.

[0019] The preparation of a first electroplated metal layer, at least one second electroplated metal layer, and a molding compound layer on the surface of a wafer to be packaged includes: the at least one second electroplated metal layer being disposed between the first electroplated metal layer and the wafer to be packaged; the molding compound layer covering the at least one second electroplated metal layer; the first electroplated metal layer being electrically connected to the wafer to be packaged through the at least one second electroplated metal layer; the first connection portion being in direct contact with and electrically connected to the second electroplated metal layer adjacent to the first electroplated metal layer; and the second electroplated metal layer adjacent to the wafer to be packaged being in direct contact with and electrically connected to the wafer to be packaged.

[0020] Optionally, preparing a first electroplated metal layer and a molding compound layer on the surface of the wafer to be packaged includes:

[0021] Set a molding compound to cover the wafer to be packaged.

[0022] A first through-hole is provided on the molding layer on one side of the wafer to be packaged.

[0023] The first electroplated metal layer is prepared on the surface of the encapsulation layer where the first through hole is located by an electroplating process.

[0024] Optionally, the fabrication of a first electroplated metal layer, at least one second electroplated metal layer, and a molding compound layer on the surface of the wafer to be packaged includes:

[0025] Set a molding compound to cover the wafer to be packaged.

[0026] A second via is provided on the molding layer on one side of the wafer to be packaged.

[0027] A first second electroplated metal layer is prepared on the surface of the molding compound with the second through-hole by an electroplating process; wherein each second electroplated metal layer includes a planar portion and a second connecting portion that are interconnected; the second connecting portion of the same second electroplated metal layer is disposed on the side of the planar portion adjacent to the wafer to be packaged; the second connecting portion of the first second electroplated metal layer is disposed in the second through-hole, and the second connecting portion of the first second electroplated metal layer is in direct contact and electrically connected to the wafer to be packaged.

[0028] A molding compound is disposed on the side of the first second electroplated metal layer away from the wafer to be packaged; wherein the molding compound covers the first second electroplated metal layer.

[0029] The first through-hole is provided in the molding layer on the side of the first layer, the second electroplated metal layer, away from the wafer to be packaged.

[0030] A first electroplated metal layer is prepared on the surface of the molding compound where the first through hole is provided by an electroplating process; wherein, the first connecting portion passes through the first through hole and directly contacts and electrically connects with the planar portion of the first layer of the second electroplated metal layer.

[0031] Optionally, after depositing the molding compound layer on the side of the first second electroplated metal layer away from the wafer to be packaged, the method further includes:

[0032] A third through-hole is provided in the molding layer on the side of the second electroplated metal layer away from the wafer to be packaged in the i-th layer.

[0033] An i+1th second electroplated metal layer is prepared on the surface of the molding layer by an electroplating process; wherein, the second connecting part of the i+1th second electroplated metal layer is disposed in the third through hole and is in direct contact with the planar part of the i-th second electroplated metal layer; i is an integer greater than or equal to 1, i takes the values ​​1, 2...n in sequence, and n is an integer greater than or equal to 1.

[0034] A molding layer is provided on the side of the second electroplated metal layer in the i+1th layer away from the wafer to be packaged.

[0035] The provision of the first through-hole in the molding compound on the side of the first layer of the second electroplated metal layer away from the wafer to be packaged includes: providing the first through-hole in the molding compound on the side of the n+1th layer of the second electroplated metal layer away from the wafer to be packaged; wherein the first connecting portion passes through the first through-hole and directly contacts and electrically connects with the planar portion of the n+1th layer of the second electroplated metal layer.

[0036] Optionally, a first electroplated metal layer and a molding compound layer are prepared on the surface of the wafer to be packaged, including:

[0037] The first connection part is prepared on the surface of the wafer to be packaged by electroplating.

[0038] A first sacrificial layer is provided on one side of the wafer to be packaged where the first connection portion is provided; wherein the first sacrificial layer is exposed on the surface of the first connection portion away from the wafer to be packaged.

[0039] External pins are formed on the side of the first sacrificial layer away from the wafer to be packaged by an electroplating process; wherein the external pins are electrically connected to the first connection portion.

[0040] Remove the first sacrificial layer.

[0041] Prepare the molding sealant layer.

[0042] Optionally, a first electroplated metal layer, at least one second electroplated metal layer, and a molding compound are prepared on the surface of the wafer to be packaged, including:

[0043] At least one second electroplated metal layer is prepared on the surface of the wafer to be packaged by an electroplating process; wherein each second electroplated metal layer includes an interconnected second connection portion and a planar portion, the second connection portion of each second electroplated metal layer is disposed on the side of the planar portion of the second electroplated metal layer adjacent to the wafer to be packaged; the second connection portion is directly in contact with the wafer to be packaged and electrically connected, or the second connection portion is directly in contact with the planar portion of another second electroplated metal layer located on the side of the wafer to be packaged adjacent to it and electrically connected; the preparation process of each second electroplated metal layer includes: preparing a second connection portion on one side of the wafer to be packaged by an electroplating process; preparing a second sacrificial layer; wherein the second sacrificial layer exposes the surface of the second connection portion away from the wafer to be packaged; and preparing a planar portion on the side of the sacrificial layer away from the wafer to be packaged by an electroplating process.

[0044] The first connection is prepared by electroplating on the surface of the wafer to be packaged, away from at least one second electroplated metal layer.

[0045] A first sacrificial layer is provided on one side of the wafer to be packaged where the first connection portion is provided; wherein the first sacrificial layer is exposed on the surface of the first connection portion away from the wafer to be packaged.

[0046] External pins are fabricated on the side of the first sacrificial layer away from the wafer to be packaged using an electroplating process.

[0047] Remove the first sacrificial layer and the second sacrificial layer.

[0048] Prepare the molding sealant layer.

[0049] Optionally, the first sacrificial layer comprises a dry film.

[0050] Optionally, after preparing a first electroplated metal layer and a molding compound layer on the surface of the wafer to be packaged; or, after preparing a first electroplated metal layer, at least one second electroplated metal layer, and a molding compound layer on the surface of the wafer to be packaged, the method further includes: providing a trench in a predetermined edge region of the first surface of the molding compound where the external pin is disposed; wherein the predetermined edge region is adjacent to the external pin, and the trench penetrates the second surface of the molding compound; the second surface of the molding compound surrounds the first surface of the molding compound and is connected to the first surface; the trench is used to provide a conductive material so that the external pin is connected to an external circuit through the conductive material.

[0051] In this embodiment, the first electroplated metal layer in the packaging structure includes interconnected external pins and a first connecting portion. The first connecting portion is in direct contact with the wafer to be packaged. Alternatively, at least one second electroplated metal layer is disposed between the first electroplated metal layer and the wafer to be packaged, and the molding layer covers at least one second electroplated metal layer. The first electroplated metal layer is electrically connected to the wafer to be packaged through at least one second electroplated metal layer. The first connecting portion is in direct contact with the second electroplated metal layer adjacent to the first electroplated metal layer, and the second electroplated metal layer adjacent to the wafer to be packaged is in direct contact with the wafer to be packaged. By directly forming the first electroplated metal layer or forming a first electroplated metal layer and a second electroplated metal layer on one side of the wafer to be packaged, the external pins, the first connecting portion, and the second electroplated metal layer of the first electroplated metal layer are all directly electroplated to form circuits without the need to purchase a carrier. This improves production efficiency, avoids warping, and enhances the bonding between the wafer to be packaged and the first and second electroplated metal layers, making delamination less likely and improving the structural stability of the packaging structure. Furthermore, the first electroplated metal layer is in direct contact with the wafer to be packaged, requiring no other medium for connection. This ensures good adhesion between the first electroplated metal layer and the wafer while reducing the process steps required to form other media. Similarly, the second electroplated metal layer is also in direct contact with the wafer, and the first and second electroplated metal layers are in direct contact with each other. This ensures good adhesion while reducing the process steps required to form the connecting media. Moreover, the wafer to be packaged, the first electroplated metal layer, and the second electroplated metal layer are all encapsulation layers, eliminating the need for other media. This reduces the number of film layers in the encapsulation structure, improves the overall structural stability, and the encapsulation layer of the entire packaging structure is a single, integrated structure, resulting in better encapsulation performance. It should be understood that the description in this section is not intended to identify key or important features of the embodiments of the invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0052] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0053] Figure 1 This is a schematic diagram of a packaging structure provided in an embodiment of the present invention.

[0054] Figure 2 This is a cross-sectional view of another packaging structure provided in an embodiment of the present invention.

[0055] Figure 3 This is a cross-sectional view of another packaging structure provided in an embodiment of the present invention.

[0056] Figure 4 This is a top view of the encapsulation structure provided in an embodiment of the present invention.

[0057] Figure 5 This is a top view of another packaging structure provided in the embodiments of the invention.

[0058] Figure 6 This is a schematic diagram of the connection between a packaging structure and an external circuit provided in an embodiment of the present invention.

[0059] Figure 7 This is a top view of the encapsulation structure after the conductive material is applied, as provided in an embodiment of the present invention.

[0060] Figure 8 This is a cross-sectional schematic diagram of another packaging structure provided in an embodiment of the present invention.

[0061] Figure 9 This is a top view of another packaging structure provided in an embodiment of the present invention.

[0062] Figure 10 This is a flowchart of a method for preparing a packaging structure provided in an embodiment of the present invention.

[0063] Figure 11 This is a schematic diagram of the encapsulation layer provided in an embodiment of the present invention.

[0064] Figure 12 This is a schematic diagram of the first through hole provided in an embodiment of the present invention.

[0065] Figure 13 This is a flowchart of another method for preparing a packaging structure provided in an embodiment of the present invention.

[0066] Figure 14 This is a schematic diagram of the preparation of the first and second electroplated metal layers provided in an embodiment of the present invention.

[0067] Figure 15 This is a schematic diagram of the preparation of a second electroplated metal layer according to an embodiment of the present invention.

[0068] Figure 16 This is a flowchart of a method for preparing a packaging structure provided in an embodiment of the present invention.

[0069] Figure 17 This is a schematic diagram after the first connecting part has been prepared.

[0070] Figure 18 This is a schematic diagram after the first sacrificial layer has been prepared.

[0071] Figure 19 This is a schematic diagram after removing the first sacrificial layer.

[0072] Figure 20 This is a flowchart of another method for preparing a packaging structure provided in an embodiment of the present invention. Detailed Implementation

[0073] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0074] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0075] This invention provides a packaging structure. Figure 1 This is a schematic diagram of a packaging structure provided in an embodiment of the present invention. Figure 2 This is a cross-sectional view of another packaging structure provided in an embodiment of the present invention, with reference to... Figure 1 and Figure 2The packaging structure includes: a molding layer 30, a wafer 10 to be packaged, and a first electroplated metal layer 100 disposed on one side of the wafer 10 to be packaged.

[0076] The molding compound 30 covers the wafer 10 to be packaged; the first electroplated metal layer 100 includes external pins 40 and a first connecting portion 110 that are interconnected; the external pins 40 are disposed outside the molding compound 30; a first through hole 81 is disposed on the side of the molding compound 30 where the external pins 40 are disposed, and the first connecting portion 110 is disposed inside the first through hole 81.

[0077] refer to Figure 1 The first connecting part 110 is in direct electrical contact with the wafer 10 to be packaged; or, refer to Figure 2 At least one second electroplated metal layer 200 is provided between the first electroplated metal layer 100 and the wafer 10 to be packaged. The molding compound 30 covers at least one second electroplated metal layer 200. The first electroplated metal layer 100 is electrically connected to the wafer 10 to be packaged through at least one second electroplated metal layer 200. The first connecting portion 110 is in direct contact with the second electroplated metal layer 200 closest to the first electroplated metal layer 100 and is electrically connected to the wafer 10 to be packaged.

[0078] In this design, the wafer 10 to be packaged is a power chip, which is not limited to GaN chips but can also be Si chips, SiC chips, or GaAs chips. The packaging structure may include one, two, or more wafers 10 to be packaged. The molding layer 30 is used to mold the wafer 10 to be packaged. The external pins 40 are used to bring out the pins of the wafer 10 to be packaged and connect them to external circuits. The first electroplated metal layer 100 can be a copper layer or other metal layers with good conductivity.

[0079] For details, please refer to Figure 1 and Figure 2 A second electroplated metal layer 200 may be included between the first electroplated metal layer 100 and the wafer 10 to be packaged. The first connecting portion 110 can be electrically connected to the wafer 10 to be packaged through the second electroplated metal layer 200. Alternatively, no other metal layer may be included between the first electroplated metal layer 100 and the wafer 10 to be packaged, and the first connecting portion 110 may be in direct contact with the wafer 10 to be packaged. Furthermore, refer to... Figure 1 The wafer 10 to be packaged and the first electroplated metal layer 100 are separated by a molding compound 30, with no other medium. (Reference) Figure 2 There are molding layers 30 between the wafer to be packaged 10 and the second electroplated metal layer 200, between the second electroplated metal layer 200 and the first electroplated metal layer 100, and between adjacent second electroplated metal layers 200, with no other medium.

[0080] The second electroplated metal layer 200 is a redistribution layer. It connects the first electroplated metal layer 100 and the wafer 10 to be packaged. The external pins 40 in the first electroplated metal layer 100 require a specific arrangement. When the external pins 40 cannot be directly connected to the wafer 10 to be packaged through the first connection portion 110, the second electroplated metal layer 200 can be provided to electrically connect the first connection portion 110 to the wafer 10 to be packaged through the second electroplated metal layer 200. The packaging structure may also include two or more wafers 10 to be packaged, and these wafers 10 can be connected to each other through the second electroplated metal layer 200. The packaging structure may include one, two, or multiple second electroplated metal layers 200. This embodiment does not specifically limit the number of second electroplated metal layers 200.

[0081] The packaging process is illustrated below using the example of the area between the wafer 10 to be packaged and the first electroplated metal layer 100, excluding the second electroplated metal layer 200:

[0082] During packaging, the wafer 10 to be packaged can be first covered with a molding compound 30, and then a first through-hole 81 can be formed on the surface of the molding compound, exposing the surface of the wafer 10 to be packaged. Then, a first electroplated metal layer 100 is formed, and the first connecting portion 110 directly contacts and electrically connects to the wafer 10 to be packaged. Alternatively, the first connecting portion 110 can be formed by electroplating on the surface of the wafer 10 to be packaged, and then a sacrificial layer can be formed, covering the wafer 10 to be packaged and exposing the surface of the first connecting portion 110 away from the wafer 10 to be packaged. Then, an external pin 40 can be formed by electroplating on the surface of the sacrificial layer, and finally, the sacrificial layer is removed to form the molding compound 30.

[0083] In this embodiment, the first electroplated metal layer 100 includes interconnected external pins 40 and a first connecting portion 110. The external pins 40 are disposed outside the molding compound 30. A first through-hole 81 is disposed on one side of the molding compound 30 where the external pins 40 are disposed, and the first connecting portion 110 is disposed within the first through-hole 81. The first connecting portion 110 is directly electrically connected to the wafer 10 to be packaged. Alternatively, at least one second electroplated metal layer 200 is disposed between the first electroplated metal layer 100 and the wafer 10 to be packaged, and the molding compound 30 covers at least one second electroplated metal layer 200. The first electroplated metal layer 100 is electrically connected to the wafer 10 to be packaged through at least one second electroplated metal layer 200, and the first connecting portion 110 is directly electrically connected to the second electroplated metal layer 200 adjacent to the first electroplated metal layer 100. The second electroplated metal layer 200 adjacent to the wafer 10 to be packaged is directly electrically connected to the wafer 10 to be packaged. By directly forming a first electroplated metal layer 100 or a first electroplated metal layer 100 and a second electroplated metal layer 200 on one side of the wafer to be packaged, the external pins 40, the first connection portion 110 of the first electroplated metal layer 100, and the second electroplated metal layer 200 are all directly electroplated without the need to purchase a carrier and form circuits. This improves production efficiency, avoids warping, and ensures better bonding between the wafer to be packaged 10 and the first and second electroplated metal layers 100 and 200, making delamination less likely and improving the structural stability of the packaging structure. Furthermore, the first electroplated metal layer 100 is in direct electrical contact with the wafer to be packaged 10, eliminating the need for other dielectric connections. This ensures good bonding between the first electroplated metal layer 100 and the wafer to be packaged 10 while reducing the number of process steps required to form other dielectrics. The second electroplated metal layer 200 is directly electrically connected to the wafer 10 to be packaged, and the first electroplated metal layer 100 is directly electrically connected to the second electroplated metal layer 200. This ensures good adhesion between them while reducing the number of process steps required to form the connecting medium. Furthermore, the wafer to be packaged, the first electroplated metal layer, and the second electroplated metal layer are all encapsulation layers, eliminating the need for other media. This reduces the number of film layers in the encapsulation structure, improves the overall structural stability, and the integrated encapsulation structure results in better overall encapsulation performance.

[0084] refer to Figure 2 Based on the above embodiments, optionally, each second electroplated metal layer 200 includes a planar portion 210 and a second connecting portion 220 that are connected to each other; the second connecting portion 220 of each second electroplated metal layer 200 is disposed on the side of the planar portion 210 of the second electroplated metal layer 200 adjacent to the wafer 10 to be packaged.

[0085] The second connection portion 220 is directly electrically connected to the wafer 10 to be packaged, or the second connection portion 220 is directly electrically connected to the planar portion 210 of another second electroplated metal layer 200 located on the side adjacent to the wafer 10 to be packaged.

[0086] The packaging process of the packaging structure including the second electroplated metal layer 200 is described below: During packaging, the wafer 10 to be packaged can first be covered with a molding compound 30. Then, a second through-hole 82 is formed on the surface of the molding compound, exposing the surface of the wafer 10 to be packaged. Then, the second electroplated metal layer 200 is formed by electroplating. The second connecting part 220 is directly in contact with the wafer 10 to be packaged and electrically connected. Then, the molding compound 30 is formed on the surface of the second electroplated metal layer 200, covering the second electroplated metal layer 200. When the packaging structure includes only one layer of the second electroplated metal layer 200, a first through-hole 81 is formed on the surface of the molding compound 30 of the second electroplated metal layer 200, and then the first electroplated metal layer 100 is formed by electroplating. When the packaging structure includes two or more second electroplated metal layers 200, a third through hole is formed on the surface of the first second electroplated metal layer 200 by the molding layer 30, and then the second second electroplated metal layer 200 is formed by electroplating, and so on, to form the last second electroplated metal layer 200. Then the molding layer 30 is formed on the surface of the last second electroplated metal layer 200, the first through hole 81 is formed on the molding layer 30, and the first electroplated metal layer 100 is formed by electroplating.

[0087] Alternatively, a second connection portion 220 can be formed by electroplating on the surface of the wafer 10 to be packaged. Then, a sacrificial layer is formed, which covers the wafer 10 to be packaged and exposes the surface of the second connection portion 220 away from the wafer 10 to be packaged. Then, a planar portion 210 is formed by electroplating on the surface of the sacrificial layer. Then, the second connection portion 220 is formed, another sacrificial layer is formed, and then the planar portion 210 is formed, until the planar portion 210 of the last second electroplated metal layer 200 is formed. Then, the first connection portion 110 is prepared, and another sacrificial layer is formed, which exposes the surface of the first connection portion 110 away from the wafer 10 to be packaged. Then, an external pin 40 is formed by electroplating on the surface of the sacrificial layer. After that, the sacrificial layer is removed and a molding layer 30 is formed.

[0088] In this embodiment, by setting a second electroplated metal layer 200, the first electroplated metal layer 100 is electrically connected to the wafer 10 to be packaged through the second electroplated metal layer 200. When the package structure includes two or more wafers 10 to be packaged, different wafers 10 to be packaged can also be connected through the second electroplated metal layer 200, making the arrangement of the external pins 40 in the first electroplated metal layer 100 more flexible. Furthermore, the second electroplated metal layer 200 is directly electroplated, eliminating the need to purchase a carrier and form circuits, which can improve production efficiency and avoid warping. The bonding between the wafer 10 to be packaged and the second electroplated metal layer 200 is better, less prone to delamination, and improves the structural stability of the package structure.

[0089] Optionally, the diameter of the first through-hole 81 is greater than or equal to 100 micrometers; the material of the encapsulation layer 30 includes resin.

[0090] Specifically, the diameter of the first through-hole 81 is greater than or equal to 100 micrometers, resulting in a larger contact area between the first connection portion 110 and the wafer 10 to be packaged or the second electroplated metal layer 200, and a more stable connection. Furthermore, the diameter of the second through-hole 82 is greater than or equal to 100 micrometers, resulting in a larger contact area between the second connection portion 220 and the wafer 10 to be packaged or the second electroplated metal layer 200, and a more stable connection.

[0091] Figure 3 This is a cross-sectional view of another packaging structure provided in an embodiment of the present invention. Figure 4 This is a top view of the molding structure provided in an embodiment of the present invention, with reference to... Figure 3 and Figure 4 Based on the above embodiments, optionally, a groove 31 is provided in the preset edge region 101 of the first surface 301 of the molding compound 30 where the external pin 40 is provided. The preset edge region 101 is adjacent to the external pin 40, and the groove 31 penetrates the second surface 302 of the molding compound 30. The second surface 302 of the molding compound 30 surrounds the first surface 301 of the molding compound 30 and is connected to the first surface 301. The groove 31 is used to provide conductive material so that the external pin 40 is connected to the external circuit through the conductive material.

[0092] The number of grooves 31 in each preset edge region 101 can be one, two, or more. For example, refer to... Figure 4 The preset edge region 101 is adjacent to the preset edge 401 of the external pin 40; the preset edge region 101 is provided with a plurality of grooves 31, which are arranged sequentially along the preset edge 401, or, Figure 5 This is a top view of another packaging structure provided in the embodiments of the invention, see reference. Figure 5 A groove 31 is provided in the preset edge area 101, and the groove 31 extends along the preset edge 401.

[0093] Specifically, Figure 6 This is a schematic diagram illustrating the connection between a packaging structure and an external circuit according to an embodiment of the present invention. Figure 7 This is a top view of the encapsulation structure after the conductive material is applied, as provided in an embodiment of the present invention. (Reference) Figure 6 and Figure 7 The trench 31 is used to accommodate conductive material 62, such as tin. The conductive material 62 fills the trench 31 and extends from it to the surface of the external pin 40, connecting with and connecting the external pin 40 to the external circuit board 70. The trench 31 penetrates the second surface 302 of the molding compound 30, meaning it extends towards the edge of the first surface 301 away from the external pin 40 and penetrates that edge. By providing the trench 31, the conductive material 62 can be disposed within it. Due to the large surface area of ​​the trench 31, the contact area between the conductive material 62 and the molding compound 30 is large, thereby improving the connection stability between the conductive material 62 and the molding compound 30 and the external pin 40. Furthermore, a larger amount of conductive material 62 can be disposed within the trench 31, allowing the package structure to be more securely connected to the external circuit board 70 through the increased amount of conductive material 62, preventing detachment.

[0094] In this embodiment, a groove 31 is formed in the preset edge region 101 of the first surface 301 of the molding compound 30. The groove 31 penetrates the second surface 302 of the molding compound 30. The groove 31 is used to set conductive material 62, so that the external pin 40 is connected to the external circuit board 70 through the conductive material 62. By setting the groove 31, the conductive material 62 can be placed in the groove 31. Since the surface area of ​​the groove 31 is large, the contact area between the conductive material 62 and the molding compound 30 is large, thereby improving the connection stability between the conductive material 62 and the molding compound 30 and the external pin 40. Moreover, a large amount of conductive material 62 can be placed in the groove 31, so that the package structure can be more firmly connected to the external circuit board 70 through the conductive material 62, avoiding detachment.

[0095] Based on the above embodiments, optionally, a connecting layer 61 is provided in the trench 31, the connecting layer 61 covers the trench 31 and extends from the inside of the trench 31 to the external pin 40; the connecting layer 61 is used to improve the bonding force between the conductive material 62 and the molding layer 30.

[0096] Specifically, the connection layer 61 can be a metal layer or a layer of other materials. For example, the material of the connection layer 61 can be the same as the material of the external pin 40; for example, the connection layer 61 can be a copper layer or an aluminum layer. The connection layer 61 can be deposited on the surface of the molding compound 30 by processes such as electroplating.

[0097] By setting the connection layer 61, the bonding force between the conductive material 62 and the molding layer 30 can be further increased, and the connection stability between the conductive material and the molding layer 30 and the external pins 40 can be further improved, so that the package structure can be more firmly connected to the external circuit board 70 through the conductive material 62, and avoid falling off.

[0098] Figure 8 This is a cross-sectional schematic diagram of another packaging structure provided in an embodiment of the present invention. Optionally, based on the above embodiments, refer to... Figure 6 and Figure 8 The sidewall of the trench 31 adjacent to the external pin 40 is a stepped surface, a plane, or a curved surface.

[0099] For details, please refer to Figure 6 The sidewalls of the groove 31 are flat, which can reduce the difficulty of manufacturing the groove 31.

[0100] refer to Figure 8 The sidewalls of the groove 31 are stepped or curved, such as arc surfaces, which can increase the area of ​​the sidewalls, further increase the contact area between the conductive material and the molding layer 30, and further improve the connection stability between the conductive material, the molding layer 30 and the external pins 40.

[0101] Based on the above embodiments, optionally, the thickness of the connection layer 61 is less than the thickness of the external pin 40.

[0102] Specifically, if the thickness of the connection layer 61 is too thick, it will occupy too much space in the trench 31, resulting in the trench 31 not being able to accommodate more conductive material. By setting the thickness of the connection layer 61 to be less than the thickness of the external pin 40, the bonding force between the conductive material and the molding layer 30 can be increased, while avoiding the connection layer 61 occupying too much space in the trench 31. This ensures that more conductive material can be accommodated in the trench 31, improving the connection stability between the package structure and the external circuit board.

[0103] Based on the above embodiments, optionally, the connecting layer 61 is an electroplated metal layer.

[0104] Specifically, the connecting layer 61 can be formed on the surface of the molding layer 30 by processes such as electroplating. For example, the connecting layer 61 can be a copper layer or an aluminum layer.

[0105] Based on the above embodiments, optionally, the connection layer 61 and the external pin 40 are made of the same material. This allows the connection layer 61 to be fabricated using the same process as the external pin 40, reducing manufacturing costs.

[0106] Based on the above embodiments, optionally, refer to the following: Figure 7 The external pins include a first external pin 41, a second external pin 42, and a third external pin 43.

[0107] The first external pin 41 includes a first body portion 411 and at least two first insertion portions 412 connected to the first body portion 411. The second external pin 42 includes a second body portion 421 and at least two second insertion portions 422 connected to the second body portion 421. The first body portion 411 and the second body portion 421 extend along a first direction X, and the first insertion portions 412 and the second insertion portions 422 extend along a second direction Y and are located between the first body portion 411 and the second body portion 421.

[0108] Along the first direction X, the first insertion part 412 and the second insertion part 422 are arranged alternately in sequence, and the third external pin 43 is located between the edge of the first main body part 411 and a second insertion part 422; wherein the first direction X and the second direction Y intersect each other.

[0109] Specifically, the first external pin 41 is comb-shaped, the second external pin 42 is comb-shaped, and the first insertion part 412 and the second insertion part 422 are arranged alternately, so that the first external pin 41 and the second external pin 42 have a large area, which improves the heat dissipation speed. The first external pin 41 and the second external pin 42 are widely distributed, so that the first external pin 41 and the second external pin 42 can be connected to the wafer 10 to be packaged at a suitable position. This helps to shorten the connection path between the wafer 10 to be packaged and the first external pin 41 and the second external pin 42, so that the first external pin 41 and the second external pin 42 can collect signals nearby, reduce product resistance, and make the current distribution more uniform.

[0110] Furthermore, since the third external pin 43 is smaller than the first external pin 41 and the second external pin 42, placing the third external pin 43 between the edge of the first main body portion 411 and a second interdigitated portion 422 can prevent the third external pin 43 from being easily detached due to stress when placed at the corner, thereby improving system stability.

[0111] Based on the above embodiments, optionally, the plurality of first insert fingers 412 include first edge insert fingers 51, and the plurality of second insert fingers 422 include second edge insert fingers 52.

[0112] The other first insert finger portions 412, excluding the first edge insert finger portion 51, and the other second insert finger portions 422, excluding the second edge insert finger portion 52, are located between the first edge insert finger portion 51 and the second edge insert finger portion 52 along the first direction X.

[0113] The width of the first edge insertion portion 51 and the second edge insertion portion 52 along the first direction X is greater than the width of the other first insertion portions 412 along the first direction X, and is greater than the width of the other second insertion portions 422 along the first direction X.

[0114] Specifically, the third external pin 43 is located between the first main body portion 411 and the second edge insertion portion 52. The first edge insertion portion 51 is located at the edge of the first external pin 41, and the second edge insertion portion 52 is located at the edge of the second external pin 42. Therefore, the first edge insertion portion 51 and the second edge insertion portion 52 can be set to a wider width, thereby further increasing the heat dissipation area.

[0115] Based on the above embodiments, optionally, refer to the following: Figure 8 The packaging structure also includes: heat sink 20.

[0116] The heat sink 20 is disposed on the side of the wafer 10 to be packaged away from the external pin 40. The molding compound 30 covers the heat sink 20, and a portion of the heat sink 20 away from the surface of the wafer 10 to be packaged is exposed by the molding compound 30.

[0117] The heat sink 20 can be made of a material with good thermal conductivity, such as a metal. By placing the heat sink 20 on the side of the wafer 10 to be packaged away from the external pin 40, the wafer 10 can dissipate heat through both the heat sink 20 and the external pin 40, achieving double-sided heat dissipation. Furthermore, the portion of the surface of the heat sink 20 away from the wafer 10 exposes the molding compound 30. This improves the heat dissipation effect of the heat sink 20 and, more importantly, the molding compound 30 covers a portion of the surface of the heat sink 20, resulting in a larger coverage area on the side where the heat sink 20 is located. This facilitates the molding of the molding compound 30 and makes the overall packaging structure more stable.

[0118] Figure 9 This is a top view of another packaging structure provided in the embodiments of the present invention. Optionally, based on the above embodiments, please continue to refer to... Figure 8 and Figure 9 The heat sink 20 includes a thinned portion 22 and a protrusion 21, with the thinned portion 22 surrounding the protrusion 21; the surface of the protrusion 21 away from the wafer 10 to be packaged has a first distance D1 between it and the wafer 10 to be packaged, and the surface of the thinned portion 22 away from the wafer 10 to be packaged has a second distance D2 between it and the wafer 10 to be packaged, with the first distance D1 being greater than the second distance D2.

[0119] The molding compound 30 covers the thinned portion 22, and the protrusion 21 is away from the surface of the wafer 10 to be packaged, exposing the molding compound 30.

[0120] Specifically, the protrusion 21 protrudes outward relative to the thinning portion 22 on the side away from the wafer 10 to be packaged. The molding compound 30 covers the thinning portion 22, so that the molding compound 30 has a larger coverage area on the side of the heat sink 20 away from the wafer 10 to be packaged. This makes the molding compound 30 easier to form, makes the heat sink 20 more stable, and the surface of the protrusion 21 away from the wafer 10 to be packaged exposed by the molding compound 30 can better dissipate heat.

[0121] Based on the above embodiments, optionally, the surface of the molding layer 30 away from the external pin 40 is flush with the surface of the protrusion 21 away from the external pin 40.

[0122] This design makes the surface of the heat sink 20 in the encapsulation structure planar, resulting in a more regular shape, smaller size, and better structural stability for the entire plastic encapsulation structure.

[0123] Based on the above embodiments, optionally, the surface of the thinned portion 22 adjacent to the wafer 10 to be packaged is flush with the surface of the protrusion 21 adjacent to the wafer 10 to be packaged.

[0124] That is, the surface of the heat sink 20 adjacent to the wafer 10 to be packaged is flat. This setting allows the heat sink 20 to fit better with the wafer 10 to be packaged, so that the heat sink 20 can better conduct the heat generated by the wafer 10 to be packaged and improve the heat dissipation efficiency.

[0125] Based on the above embodiments, optionally, the ratio of the thickness of the thinned portion 22 to the thickness of the protrusion 21 is greater than or equal to 1 / 3 and less than or equal to 3 / 4.

[0126] Specifically, the protrusion 21 is the main heat dissipation part of the heat sink 20, and its thickness can be set according to heat dissipation requirements. The thinned part 22 is the thinnest part of the heat sink 20. If the thickness of the thinned part 22 is too thin, it will hinder heat conduction and affect the structural strength of the thinned part 22. If the thickness of the thinned part 22 is too thick, it will affect the thickness of the molding layer 30 covering the thinned part 22, which will hinder the molding of the molding layer 30. By setting the ratio of the thickness of the thinned part 22 to the thickness of the protrusion 21 to be greater than or equal to 1 / 3 and less than or equal to 3 / 4, the thickness of the thinned part 22 will not be too thin and affect the structural strength of the heat sink, nor will it be too thick and affect the molding of the molding layer 30. For example, the ratio of the thickness of the thinned part 22 to the thickness of the protrusion 21 is 1 / 2.

[0127] Based on the above embodiments, optionally, the distance S between the edge of the thinned portion 22 away from the protrusion 21 and the edge of the thinned portion 22 adjacent to the protrusion 21 is greater than or equal to 100 micrometers.

[0128] That is, along the direction from the protrusion 21 to the thinning part 22, the width of the thinning part 22 is greater than or equal to 100 micrometers. This setting makes the area covered by the molding compound 30 of the heat sink 20 larger, avoiding the situation where the coverage area is too small and the molding compound 30 cannot be formed on the surface of the heat sink 20.

[0129] Based on the above embodiments, optionally, the distance L between the edge of the vertical projection of the molding compound 30 onto the surface of the wafer 10 adjacent to the heat sink 20 and the edge of the vertical projection of the heat sink 20 onto the surface of the wafer 10 adjacent to the heat sink 20 is greater than or equal to 100 micrometers.

[0130] The distance L between the side of the molding compound 30 and the side of the heat sink 20 is greater than or equal to 100 micrometers, which makes the part of the molding compound 30 covering the side of the heat sink 20 thicker, which is beneficial to the molding of the molding compound 30.

[0131] Based on the above embodiments, optionally, the heat sink 20 covers the wafer 10 to be packaged in the vertical projection of the wafer 10 to be packaged.

[0132] That is, the area of ​​the heat sink 20 is greater than or equal to the area of ​​the surface of the wafer 10 to be packaged adjacent to the heat sink 20, so that the heat sink 20 can better conduct the heat generated by the wafer 10 to be packaged and improve the heat dissipation speed.

[0133] Based on the above embodiments, optionally, a thermally conductive connection layer 50 is provided between the heat sink 20 and the wafer 10 to be packaged.

[0134] Specifically, the thermally conductive bonding layer 50 is used to bond the heat sink 20 to the wafer 10 to be packaged and to conduct heat. For example, the thermally conductive bonding layer 50 can be a thermally conductive adhesive, etc. By providing the thermally conductive bonding layer 50, the heat sink 20 and the wafer 10 to be packaged can be stably connected, and there is a faster heat conduction speed between the wafer 10 to be packaged and the heat sink 20, resulting in a faster heat dissipation speed for the packaged structure.

[0135] This invention also provides a method for preparing a packaging structure, the method comprising:

[0136] Provide wafers to be packaged.

[0137] A first electroplated metal layer and a molding compound are prepared on the surface of the wafer to be packaged; or, a first electroplated metal layer, at least one second electroplated metal layer, and a molding compound are prepared on the surface of the wafer to be packaged.

[0138] The molding compound covers the wafer to be packaged; the first electroplated metal layer includes interconnected external pins and a first connecting portion; the external pins are disposed outside the molding compound; a first through hole is disposed on the side of the molding compound where the external pins are disposed, and the first connecting portion is disposed inside the first through hole.

[0139] Preparing a first electroplated metal layer and a molding compound layer on the surface of a wafer to be packaged includes: a first connecting portion being in direct contact with and electrically connected to the wafer to be packaged.

[0140] The preparation of a first electroplated metal layer, at least one second electroplated metal layer, and a molding compound layer on the surface of a wafer to be packaged includes: at least one second electroplated metal layer disposed between the first electroplated metal layer and the wafer to be packaged; the molding compound layer covering at least one second electroplated metal layer; the first electroplated metal layer being electrically connected to the wafer to be packaged through at least one second electroplated metal layer; a first connection portion being in direct contact with the second electroplated metal layer adjacent to the first electroplated metal layer; and the second electroplated metal layer adjacent to the wafer to be packaged being in direct contact with the wafer to be packaged.

[0141] Combination Figure 1 and Figure 2 In this embodiment, a first electroplated metal layer 100 or a first electroplated metal layer 100 and a second electroplated metal layer 200 are formed directly on one side of the wafer to be packaged. The external pins 40, the first connection portion 110 of the first electroplated metal layer 100, and the second electroplated metal layer 200 are all directly electroplated, eliminating the need to purchase a carrier and form circuits. This improves production efficiency and avoids warping, resulting in better bonding between the wafer to be packaged 10 and the first and second electroplated metal layers 100 and 200, reducing the likelihood of delamination and improving the structural stability of the packaging structure. Furthermore, the first electroplated metal layer 100 is in direct electrical contact with the wafer to be packaged 10, eliminating the need for other media connections. This ensures good bonding between the first electroplated metal layer 100 and the wafer to be packaged 10 while reducing the number of process steps required to form other media. The second electroplated metal layer 200 is directly in contact with the wafer 10 to be packaged and electrically connected. The first electroplated metal layer 100 and the second electroplated metal layer 200 are directly in contact with each other and electrically connected. While ensuring good adhesion between them, the process steps to form the medium connecting them can be reduced.

[0142] Figure 10 This is a flowchart of a method for fabricating a packaging structure according to an embodiment of the present invention, see reference. Figure 10 The methods for fabricating the encapsulation structure include:

[0143] S100 provides wafers to be packaged.

[0144] S110. Set a molding compound to cover the wafer to be packaged.

[0145] Figure 11 This is a schematic diagram of the encapsulation layer provided in an embodiment of the present invention, for reference. Figure 11The molding compound 30 covers the wafer 10 to be packaged. In addition, before the molding compound 30 is applied, a heat sink 20 can be applied to the surface of the wafer 10 to be packaged via a thermally conductive connection layer 50.

[0146] S120. A first through-hole is provided on the molding layer on one side of the wafer to be packaged.

[0147] Figure 12 This is a schematic diagram of the first through hole provided in an embodiment of the present invention, for reference. Figure 12 A first through hole 81 can be set in the plastic seal layer 30 by laser drilling.

[0148] S130. A first electroplated metal layer is prepared on the surface of the plastic sealant layer where the first through hole is provided by an electroplating process.

[0149] refer to Figure 1 A first electroplated metal layer 100 is formed on the surface of the molding layer 30 to form a molding structure.

[0150] In this embodiment, a first electroplated metal layer is formed directly on one side of the wafer to be packaged by electroplating. The external pins and the first connection part of the first electroplated metal layer are directly electroplated to form the circuit without purchasing a carrier. This can improve production efficiency, avoid warping, and improve the bonding between the wafer to be packaged and the first electroplated metal layer. It is not easy to delaminate, thus improving the structural stability of the packaging structure.

[0151] Figure 13 This is a flowchart illustrating another method for preparing a packaging structure provided in this embodiment of the invention. Figure 14 This is a schematic diagram of the preparation of the first and second electroplated metal layers according to an embodiment of the present invention. Based on the above embodiment, optionally... Figure 13 and Figure 14 The methods for fabricating the encapsulation structure include:

[0152] S300 provides wafers to be packaged.

[0153] S310. Set a molding compound to cover the wafer to be packaged.

[0154] S320. A second through-hole is provided on the molding layer on one side of the wafer to be packaged.

[0155] Specifically, a second through-hole 82 is provided on the molding layer 30 on the surface of the wafer 10 to be packaged.

[0156] S330. A first second electroplated metal layer 200 is prepared on the surface of the molding compound 30 where the second through hole 82 is provided by an electroplating process; wherein, each second electroplated metal layer 200 includes a planar portion 210 and a second connecting portion 220 connected to each other; the second connecting portion 220 of the same second electroplated metal layer 200 is disposed on the side of the planar portion 210 adjacent to the wafer 10 to be packaged; the second connecting portion 220 of the first second electroplated metal layer 200 is disposed in the second through hole 82, and the second connecting portion 220 of the first second electroplated metal layer 200 is in direct contact and electrically connected to the wafer 10 to be packaged.

[0157] Continue to refer to Figure 14 , Figure 14 The packaging structure includes a second electroplated metal layer 200, which is equivalent to a first second electroplated metal layer 200. The second connection portion 220 of the first second electroplated metal layer 200 is directly electrically connected to the wafer 10 to be packaged.

[0158] S340, a molding compound 30 is provided on the side of the first second electroplated metal layer 200 away from the wafer 10 to be packaged; wherein the molding compound 30 covers the first second electroplated metal layer 200.

[0159] Specifically, a molding layer 30 is prepared to cover the second electroplated metal layer 200.

[0160] S350, a first through-hole 81 is provided in the molding layer 30 on the side of the first second electroplated metal layer 200 away from the wafer 10 to be packaged.

[0161] S360. A first electroplated metal layer is prepared on the surface of the plastic sealant layer where the first through hole is provided by an electroplating process; wherein, the first connecting part 110 passes through the first through hole 81 and directly contacts and electrically connects with the planar part 210 of the first second electroplated metal layer 200.

[0162] Based on the above embodiments, optionally, after providing a molding compound layer on the side of the first second electroplated metal layer away from the wafer to be packaged, the method further includes:

[0163] A third via is provided in the molding layer on the side of the i-th second electroplated metal layer away from the wafer to be packaged;

[0164] A second electroplated metal layer of layer i+1 is prepared on the surface of the molding layer by electroplating process; wherein, the second connecting part of the second electroplated metal layer of layer i+1 is disposed in the third through hole and is in direct contact with the planar part of the second electroplated metal layer of layer i; i is an integer greater than or equal to 1, i takes the values ​​1, 2...n in sequence, and n is an integer greater than or equal to 1;

[0165] A molding layer is provided on the side of the second electroplated metal layer in the (i+1)th layer away from the wafer to be packaged;

[0166] The first through-hole is provided in the molding layer on the side of the first layer of the second electroplated metal layer away from the wafer to be packaged, including:

[0167] A first through-hole is provided in the molding layer on the side of the second electroplated metal layer away from the wafer to be packaged in the (n+1)th layer; wherein, the first connecting part passes through the first through-hole and directly contacts and electrically connects with the planar part of the second electroplated metal layer in the (n+1)th layer.

[0168] Figure 15 This is a schematic diagram of the preparation of a second electroplated metal layer according to an embodiment of the present invention, which is exemplary and can be referred to. Figure 15 If n=1, the packaging structure fabrication process is as follows: During packaging, a molding compound 30 is first used to cover the wafer 10 to be packaged. Then, a second through-hole 82 is formed on the surface of the molding compound 30, exposing the surface of the wafer 10 to be packaged. A first second electroplated metal layer 200 is then formed by electroplating. The second connecting portion 220 of the first second electroplated metal layer 200 is directly in contact with and electrically connected to the wafer 10 to be packaged. Then, a molding compound 30 is formed on the surface of the first second electroplated metal layer 200, covering the first second electroplated metal layer 200. A third through-hole 83 is formed on the molding compound 30 on the surface of the first second electroplated metal layer 200. Then, a second second electroplated metal layer 200 is formed by electroplating. A molding compound 30 is then formed on the surface of the second second electroplated metal layer 200, and a first through-hole 81 is formed on the molding compound 30. A first electroplated metal layer 100 is then formed by electroplating.

[0169] In this embodiment, the second electroplated metal layer 200 is formed directly by electroplating, without the need to purchase a carrier and form circuits, which can improve production efficiency and avoid warping. The bonding between the wafer to be packaged 10 and the second electroplated metal layer 200 is better, and it is not easy to delaminate, thus improving the structural stability of the packaging structure.

[0170] This invention also provides a method for preparing a packaging structure. Figure 16 This is a flowchart of a method for fabricating a packaging structure according to an embodiment of the present invention, see reference. Figure 16 The methods for fabricating the encapsulation structure include:

[0171] S200 provides wafers to be packaged.

[0172] S210. The first connection part is prepared on the surface of the wafer to be packaged by electroplating process.

[0173] Figure 17 This is a schematic diagram showing the fabrication of the first connecting part. (Refer to...) Figure 17 The first connection portion 110 is formed directly on the surface of the wafer 10 to be packaged by electroplating. The shape and position of the first connection portion 110 formed directly on the surface of the wafer 10 to be packaged are more accurate, and it can be connected to the wafer 10 to be packaged more firmly and precisely.

[0174] S220. A first sacrificial layer is provided on the side of the wafer to be packaged where the first connection portion is provided. The first sacrificial layer is exposed on the surface of the first connection portion away from the wafer to be packaged.

[0175] Figure 18 This is a schematic diagram after the first sacrificial layer has been prepared. (See reference) Figure 18 The first sacrificial layer 90 can be directly applied to the surface of the wafer 10 to be packaged by coating or other methods, or the formed sacrificial layer can be directly attached to the surface of the wafer 10 to be packaged by bonding or other methods. The first sacrificial layer 90 covers the surface of the wafer 10 to be packaged adjacent to the first connection portion 110. The first sacrificial layer 90 is used to form a flat surface for electroplating external pins 40 on its surface.

[0176] S230. An external pin is prepared on the side of the first sacrificial layer away from the wafer to be packaged by an electroplating process. The external pin is electrically connected to the first connection portion.

[0177] S240, Remove the first sacrificial layer.

[0178] Specifically, Figure 19 This is a schematic diagram after removing the first sacrificial layer. (See reference) Figure 19 The first sacrificial layer can be removed by rinsing or other methods. For example, it can be removed using a specific etching solution.

[0179] S250. Prepare the molding compound layer. The molding compound layer covers the wafer to be packaged and the first interconnection portion, and exposes the external pins.

[0180] In this embodiment, the first connection portion 110 is formed by electroplating first, making the position and shape of the first connection portion 110 more controllable, allowing for a more stable and precise connection between the first connection portion 110 and the wafer 10 to be packaged. By directly electroplating the external pins 40 and the first connection portion 110, there is no need to purchase a carrier and form the circuit, which can improve production efficiency, avoid warping, and improve the bonding between the wafer 10 to be packaged and the first electroplated metal layer 100, making it less prone to delamination and improving the structural stability of the packaging structure.

[0181] Figure 20 This is a flowchart of another method for preparing a packaging structure provided in an embodiment of the present invention, see reference. Figure 20 The methods for fabricating the encapsulation structure include:

[0182] S400 provides wafers to be packaged.

[0183] S410. At least one second electroplated metal layer is prepared on the surface of the wafer to be packaged by an electroplating process; wherein each second electroplated metal layer includes a second connecting portion and a planar portion that are interconnected, and the second connecting portion of each second electroplated metal layer is disposed on the side of the planar portion of the second electroplated metal layer adjacent to the wafer to be packaged; the second connecting portion is directly electrically connected to the wafer to be packaged, or the second connecting portion is electrically connected to the planar portion of another second electroplated metal layer located on the side of the wafer to be packaged adjacent to it.

[0184] The preparation process of each second electroplated metal layer in S410 includes: S261, preparing a second connection part on one side of the wafer to be packaged by electroplating; S262, preparing a second sacrificial layer; wherein the second sacrificial layer exposes the surface of the second connection part away from the wafer to be packaged; S263, preparing a planar part on the side of the second sacrificial layer away from the wafer to be packaged by electroplating.

[0185] S420. A first connection is prepared on the surface of at least one second electroplated metal layer away from the wafer to be packaged by an electroplating process.

[0186] S430. A first sacrificial layer is provided on one side of the wafer to be packaged where the first connection portion is provided; wherein the first sacrificial layer exposes the surface of the first connection portion away from the wafer to be packaged.

[0187] S440. External pins are prepared on the side of the first sacrificial layer away from the wafer to be packaged by an electroplating process.

[0188] S450, Remove the first sacrificial layer and the second sacrificial layer.

[0189] S460, Prepare the molding layer.

[0190] Specifically, the second sacrificial layer closest to the wafer to be packaged covers the surface of the wafer to be packaged where the second connection portion is disposed. The coverage range of all the second sacrificial layers in the vertical projection of the plane where the wafer to be packaged is located can be the same. The second sacrificial layer is used to form a flat surface so as to form a planar portion by electroplating on its surface.

[0191] The specific fabrication process of the packaging structure can be referred to as follows: Figure 2 First, a second connection portion 220 of a first second electroplated metal layer 200 is formed on the surface of the wafer 10 to be packaged by electroplating. Then, a second sacrificial layer is provided, which covers the wafer 10 to be packaged and exposes the second connection portion 220 of the first second electroplated metal layer 200 away from the surface of the wafer 10 to be packaged. Then, a planar portion 210 of the first second electroplated metal layer 200 is formed on the surface of the second sacrificial layer by electroplating.

[0192] If the packaging structure includes only one second electroplated metal layer 200, the first connection portion 110 is directly electroplated on the planar portion 210 of the first second electroplated metal layer 200, and then a first sacrificial layer is formed. The first sacrificial layer exposes the surface of the first connection portion 110 away from the wafer 10 to be packaged. Then, external pins 40 are electroplated on the surface of the first sacrificial layer. After that, the first sacrificial layer and the second sacrificial layer are removed and a molding compound 30 is formed.

[0193] If the packaging structure includes two or more second electroplated metal layers 200, a second connection portion 220 of the second electroplated metal layer 200 is formed on the surface of the planar portion 210 of the first second electroplated metal layer 200, then a second sacrificial layer is formed, then the planar portion 210 of the second second electroplated metal layer 200 is formed, until the planar portion 210 of the last second electroplated metal layer 200 is formed, then a first connection portion 110 is prepared, then a first sacrificial layer is formed, the first sacrificial layer is exposed on the surface of the first connection portion 110 away from the wafer 10 to be packaged, then an external pin 40 is formed by electroplating on the surface of the first sacrificial layer, then the first sacrificial layer and the second sacrificial layer are removed and a molding compound 30 is formed.

[0194] Alternatively, the first sacrificial layer and the second sacrificial layer can be removed together after the first electroplated metal layer is prepared, and then a molding compound layer can be prepared together. Alternatively, after each second electroplated metal layer is prepared, the second sacrificial layer used for that second electroplated metal layer can be removed, and then a molding compound layer can be prepared to cover the second electroplated metal layer, exposing the planar portion of the second electroplated metal layer away from the surface of the wafer to be packaged. In this way, after the first electroplated metal layer is finally prepared, only the first sacrificial layer needs to be removed, and then a molding compound layer can be prepared to cover the first connection portion.

[0195] Based on the above embodiments, optionally, the first sacrificial layer includes a dry film. The second sacrificial layer includes a dry film.

[0196] Based on the above embodiments, optionally, after preparing a first electroplated metal layer and a molding compound layer on the surface of the wafer to be packaged; or, after preparing a first electroplated metal layer, at least one second electroplated metal layer, and a molding compound layer on the surface of the wafer to be packaged, the process includes:

[0197] A groove is provided in a predetermined edge area of ​​the first surface of the molding compound on which the external pins are provided; wherein the predetermined edge area is adjacent to the external pins, and the groove penetrates the second surface of the molding compound; the second surface of the molding compound surrounds the first surface of the molding compound and is connected to the first surface; the groove is used to provide conductive material so that the external pins are connected to an external circuit through the conductive material.

[0198] Specifically, grooves are formed in the molding layer using a laser drilling process. Furthermore, an bonding layer can be formed within the grooves by electroplating.

[0199] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0200] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A package structure, characterized by, The package structure comprises: a plastic sealing layer, a wafer to be packaged, and a first electroplated metal layer arranged on one side of the wafer to be packaged; the plastic sealing layer covers the wafer to be packaged; the first electroplated metal layer comprises mutually connected external pins and a first connecting portion; the external pins are arranged outside the plastic sealing layer; one side of the plastic sealing layer, on which the external pins are arranged, is provided with a first through hole, and the first connecting portion is arranged in the first through hole; the first connecting portion is directly in contact with and electrically connected to the wafer to be packaged; or at least one second electroplated metal layer is further arranged between the first electroplated metal layer and the wafer to be packaged, the plastic sealing layer covers the at least one second electroplated metal layer, the first electroplated metal layer is electrically connected to the wafer to be packaged through the at least one second electroplated metal layer, the first connecting portion is directly in contact with and electrically connected to the second electroplated metal layer closest to the first electroplated metal layer, and the second electroplated metal layer closest to the wafer to be packaged is directly in contact with and electrically connected to the wafer to be packaged; a preset edge region of a first surface of the plastic sealing layer, on which the external pins are arranged, is provided with a groove, the preset edge region is adjacent to the external pins, and the groove penetrates through a second surface of the plastic sealing layer; the second surface of the plastic sealing layer surrounds the first surface of the plastic sealing layer and is connected to the first surface; and the groove is used for arranging conductive material, so that the external pins are connected to external circuits through the conductive material.

2. The package structure according to claim 1, wherein: each second electroplated metal layer comprises a planar portion and a second connecting portion which are mutually connected; and the second connecting portion of each second electroplated metal layer is arranged on a side of the planar portion of the second electroplated metal layer which is adjacent to the wafer to be packaged; the second connecting portion is directly in contact with and electrically connected to the wafer to be packaged, or the second connecting portion is directly in contact with and electrically connected to the planar portion of another second electroplated metal layer which is located on a side adjacent to the wafer to be packaged.

3. The package structure according to claim 1, wherein: a connecting layer is arranged in the groove, the connecting layer covers the groove and extends from the groove to the external pins; and the connecting layer is used for improving the bonding force between the conductive material and the plastic sealing layer.

4. The package structure according to claim 1, wherein: the external pins comprise first external pins, second external pins, and third external pins; the first external pins comprise a first main body portion and at least two first finger portions connected to the first main body portion, the second external pins comprise a second main body portion and at least two second finger portions connected to the second main body portion, the first main body portion and the second main body portion extend along a first direction, and the first finger portions and the second finger portions extend along a second direction and are located between the first main body portion and the second main body portion; in the first direction, the first finger portions and the second finger portions are arranged alternately in sequence, and the third external pins are located between the edge of the first main body portion and one of the second finger portions; and the first direction and the second direction intersect with each other.

5. The package structure of claim 1, wherein, Further comprising: a heat dissipation member; The heat dissipation member is arranged on a side of the wafer to be packaged away from the external pin, the plastic encapsulation layer covers the heat dissipation member, and a part of the heat dissipation member away from the surface of the wafer is exposed to the plastic encapsulation layer.

6. The package structure of claim 1, wherein: The first via has an aperture greater than or equal to 100 microns. The plastic encapsulation layer comprises a resin.

Images