Board-level three-dimensional packaging structure and electronic equipment

Abstract

The utility model provides a board-level three-dimensional packaging structure and electronic equipment. The board-level three-dimensional packaging structure comprises a first board body, a second board body, a heating device, a plastic packaging material and a plurality of copper needle groups. Wherein the first plate body and the second plate body are stacked, the first plate body comprises a first surface and a second surface which are oppositely arranged, the first surface is a surface deviating from the second plate body, and the heating device is arranged on the first surface. The second plate body comprises a third surface and a fourth surface which are oppositely arranged, and the third surface is a surface facing the first plate body. After the first plate body and the second plate body are stacked, the second surface and the third surface are adjacently arranged, the plurality of copper needle groups are connected between the second surface and the third surface, a plastic package material is filled between the second surface and the third surface, and the plastic package material wraps the copper needles. According to the scheme, the plate-level three-dimensional packaging structure can be reduced, the heat dissipation efficiency in the heating period is improved, and the structural strength of the plate-level three-dimensional packaging structure is improved.

Description

Technical Field

[0001] This application relates to the field of electronic device technology, and in particular to a board-level three-dimensional packaging structure and electronic device. Background Technology

[0002] With the technological development in the field of electronic devices, the integration level of electronic devices is gradually increasing. Electronic devices contain single boards. As the number of electronic components in electronic devices gradually increases, in order to improve the integration level of electronic devices, a stacked packaging method can be used to form a board-level three-dimensional packaging structure to improve the integration level of single boards.

[0003] Specifically, Figure 1 This is a schematic diagram of a three-dimensional stacked structure at the board level in the prior art. Figure 1 This specifically illustrates a cross-sectional schematic diagram of a plate-level three-dimensional stacked structure. For example... Figure 1 As shown, in the prior art, the board-level three-dimensional stacked structure includes a stacked first board 1 and a second board 2, with a frame board 3 (FB) disposed between the first board 1 and the second board 2. A heat-generating device 4 is disposed on the side of the first board 1 opposite to the second board 2, and electronic devices 5 can also be disposed on the first board 1 and the second board 2. The board-level three-dimensional stacked structure in this scheme has a high degree of integration, but the thickness of the board-level three-dimensional stacked structure is also relatively thick, which is not conducive to the thinning of electronic devices. In addition, the cavity between the first board 1 and the second board 2 is relatively large due to the use of the frame board 3 to support and connect the first board 1 and the second board 2, resulting in weak strength and low reliability of the board-level three-dimensional stacked structure. The side of the heat-generating device 4 opposite to the first board 1 can be provided with structures such as thermally conductive gel 6 and shielding cover 7 for heat dissipation (the shielding cover 7 can conduct heat to connect other heat dissipation structures). However, the side of the heat-generating device 4 opposite to the shielding cover 7 is opposite to the cavity, which is not conducive to heat dissipation of the heat-generating device 4, resulting in poor heat dissipation effect of the heat-generating device 4. The electrical connection between the first plate 1 and the second plate 2 needs to be achieved using the frame plate 3, making it difficult to achieve a high-density layout between the first plate 1 and the second plate 2. Utility Model Content

[0004] This application provides a board-level three-dimensional packaging structure and electronic device. This solution can improve the heat dissipation efficiency of heat-generating devices and enhance the structural strength of the board-level three-dimensional packaging structure.

[0005] In a first aspect, this application provides a board-level three-dimensional packaging structure, which includes a first board, a second board, a heat-generating device, a molding compound, and a plurality of copper pin assemblies. The first and second boards are stacked. The first board includes a first surface and a second surface disposed opposite to each other, the first surface being the surface facing away from the second board, and the heat-generating device is disposed on the first surface. The second board includes a third surface and a fourth surface disposed opposite to each other, the third surface being the surface facing the first board. After the first and second boards are stacked, the second and third surfaces are disposed opposite to each other, and the plurality of copper pin assemblies are connected between the second and third surfaces, with the space between the second and third surfaces filled with molding compound, which encapsulates the copper pins. Compared to air, molding compound has better heat dissipation performance. Furthermore, by filling the space between the second and third surfaces, molding compound enhances the overall heat dissipation of the board-level 3D packaging structure. The copper pin assembly transfers heat from the first board to the second board, enabling bi-lateral heat dissipation and further improving heat dissipation. The molding compound encapsulates the copper pins, effectively protecting them, and by filling the space between the second and third surfaces, it increases the overall strength of the board-level 3D packaging structure, making it less prone to warping and deformation.

[0006] Furthermore, because the first and second plates are encapsulated with molding compound, the spacing between them can be smaller (in existing technologies, a frame plate structure is used, and to prevent warping, the frame plate thickness cannot be too thin). This facilitates the thinning of the board-level three-dimensional packaging structure, thereby contributing to the thinning of electronic devices. The copper pin arrangement is also more flexible, thus simplifying the complexity of the metal pattern on the second surface of the first plate.

[0007] In one technical solution, at least some of the copper needle groups have their orthographic projections onto the first plate located within the orthographic projection of the heating element on the first plate. This facilitates the transfer of heat from the heating element to the second plate, improving the heat dissipation efficiency of the heating element. The area directly opposite the heating element has a higher heat concentration; placing copper needle groups in this area helps to specifically enhance the heat dissipation capacity of the heating element.

[0008] Furthermore, the aforementioned first plate also includes one or more first through holes, each containing a metal pillar, and the through hole penetrates the first plate. These first through holes facilitate the transfer of heat generated by heat-generating devices on the first surface of the first plate to the second surface, and then conduction via the copper pin assembly to the second plate for heat dissipation. The metal pillar has good thermal conductivity; therefore, the aforementioned one or more first through holes can be partially used for signal transmission and partially for heat conduction, thereby improving the heat dissipation capability of the board-level three-dimensional packaging structure while simultaneously completing signal transmission.

[0009] Similarly, the second plate may also include one or more second through-holes, each containing a metal pillar, and the through-hole penetrates the second plate. These second through-holes facilitate the transfer of heat from the third surface of the second plate to the fourth surface, and then through the copper pin assembly to the second plate for heat dissipation. The metal pillars have good thermal conductivity, which can improve the heat dissipation capability of the board-level three-dimensional packaging structure.

[0010] In one technical solution, the aforementioned plurality of copper needle groups include functional copper needle groups, which can be used to transmit electrical signals. Specifically, the functional copper needle groups are electrically connected to the circuitry of the first board and / or the circuitry of the second board. While transmitting signals, these functional copper needle groups can also be used to transfer heat.

[0011] In one technical solution, the aforementioned plurality of copper pin groups include a structural copper pin group. This structural copper pin group is not used for transmitting electrical signals; rather, it is structurally connected between the first plate and the second plate, primarily for heat transfer and enhancing structural strength. The structural copper pin group is electrically insulated from both the first and second plates. This is beneficial for improving the heat dissipation efficiency of the heat-generating device. In particular, the structural copper pin group can be positioned directly below the heat-generating device to specifically enhance its heat dissipation effect.

[0012] The diameter of the aforementioned copper pin group is 0.15mm to 0.2mm. The smaller diameter of the copper pin group reduces the likelihood of short circuits between adjacent groups, which facilitates a high-density pin layout for the connection between the first and second boards, thereby improving signal transmission density.

[0013] In the specific technical solution, the aforementioned plurality of copper needle groups include a first copper needle group, which includes a first copper needle and a second copper needle. The molding compound includes a first molding compound and a second molding compound. The first copper needle is connected to the second surface of the first plate, and the first molding compound is fixed to the second surface of the first plate, encapsulating the first copper needle. The second copper needle is connected to the third surface of the second plate, and the second molding compound is fixed to the third surface of the second plate, encapsulating the second copper needle. The first molding compound and the second molding compound are fixedly connected, and the first copper needle and the second copper needle are electrically connected. In this solution, the copper needles and molding compound are prepared separately on the first plate and the second plate, which simplifies the manufacturing process.

[0014] Specifically, when fixing the first plate and the second plate, a non-conductive adhesive is used to connect the first molding compound and the second molding compound, that is, the first molding compound and the second molding compound are bonded together by non-conductive adhesive. A solder or conductive adhesive is used to connect the first copper needle and the second copper needle, that is, the first copper needle and the second copper needle are welded together by solder or bonded together by conductive adhesive.

[0015] A first shielding layer is provided on the side of the first plate and the first molding compound, and a second shielding layer is provided on the side of the second plate and the second molding compound. The first and second shielding layers are electrically connected. In this design, shielding can be provided around the periphery of the board-level three-dimensional packaging structure. Specifically, the first shielding layer can be a metal layer forming the surface of the first plate and the first molding compound, and the second shielding layer can be a metal layer forming the surface of the second plate and the second molding compound. The first and second shielding layers occupy less space, which is beneficial to improving the miniaturization of the board-level three-dimensional packaging structure.

[0016] To achieve a point connection between the first and second shielding layers, a conductive adhesive can be used to connect them. The first molding compound has a groove on the side facing the second molding compound, and the first shielding layer covers the inner wall of the groove, with at least a portion of the conductive adhesive contained within it. Alternatively, the second molding compound has a groove on the side facing the first molding compound, and the second shielding layer covers the inner wall of the groove, with at least a portion of the conductive adhesive contained within it. Since the conductive adhesive is at least partially contained within the groove, it is less likely to detach, which improves the reliability of the connection between the first and second shielding layers.

[0017] Secondly, this application also provides an electronic device. The electronic device includes a housing and the board-level three-dimensional packaging structure provided in the first aspect, the board-level three-dimensional packaging structure being disposed within the housing. This solution facilitates the reduction in the thickness and lightness of the electronic device and improves its operational performance. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of a board-level three-dimensional stacked structure in the prior art;

[0019] Figure 2 This is a schematic diagram of the structure of an electronic device in an embodiment of this application;

[0020] Figure 3 This is a schematic diagram of a board-level three-dimensional packaging structure in an embodiment of this application;

[0021] Figure 4 This is a schematic diagram of a board-level three-dimensional packaging structure in an embodiment of this application;

[0022] Figure 5 This is a process flow diagram of a board-level three-dimensional packaging structure in the embodiments of this application;

[0023] Figure 6 This is a process flow diagram of a board-level three-dimensional packaging structure in the embodiments of this application;

[0024] Figure 7 This is a process flow diagram of a board-level three-dimensional packaging structure in an embodiment of this application.

[0025] Figure label:

[0026] 1-First plate; 11-First surface;

[0027] 12-Second surface; 13-First through hole;

[0028] 2-Second plate; 21-Third surface;

[0029] 22 - Fourth surface; 23 - Second through hole;

[0030] 3-Frame plate; 4-Heating element;

[0031] 5-Electronic devices; 6-Thermal conductive gel;

[0032] 7-Shielding cover; 8-Copper pin assembly;

[0033] 81 - First copper needle; 82 - Second copper needle;

[0034] 83-Functional copper needle; 84-Structural copper needle;

[0035] 9 - Molding compound; 91 - First molding compound;

[0036] 92 - Second molding compound; 10 - Non-conductive adhesive;

[0037] 101 - Solder; 102 - First shielding layer;

[0038] 103 - Second shielding layer; 104 - Conductive adhesive;

[0039] 105 - Groove; 100 - Housing;

[0040] 200 - Board-level 3D packaging structure; 300 - Battery;

[0041] 400-Camera Module. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this application clearer, the application will now be described in further detail with reference to the accompanying drawings.

[0043] The terminology used in the following embodiments is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. As used in the specification and appended claims of this application, the singular expressions “a,” “an,” “the,” “the,” and “this” are intended to also include expressions such as “one or more,” unless the context clearly indicates otherwise.

[0044] References to “an embodiment” or “a specific embodiment” as used in this specification mean that one or more embodiments of this application include a particular feature, structure, or characteristic described in connection with that embodiment. The terms “comprising,” “including,” “having,” and variations thereof mean “including, but not limited to,” unless otherwise specifically emphasized.

[0045] To facilitate understanding of the three-dimensional packaging structure and electronic device provided in the embodiments of this application, its application scenarios will be introduced first below.

[0046] The electronic devices in this application can be information and communication technology (ICT) devices, communication devices (such as routers), computing devices (such as servers), network devices (such as switches), or storage devices (such as storage arrays), etc. Alternatively, they can be optical modules, vehicle-mounted devices, or terminal devices (such as mobile phones, tablets, wearable devices, or audio devices). This application does not limit the specific type of electronic device; any electronic device including a packaging structure can adopt the technical solutions provided in this application.

[0047] Figure 2 This is a schematic diagram of the structure of an electronic device in an embodiment of this application, such as... Figure 2 As shown, the electronic device in this embodiment includes a housing 100 and a board-level three-dimensional packaging structure 200, with the board-level three-dimensional packaging structure 200 disposed on the housing 100. Specifically, the board-level three-dimensional packaging structure 200 can serve as the motherboard of the electronic device. The board-level three-dimensional packaging structure 200 includes a chip and is connected to other structures of the electronic device, enabling the operation of the electronic device. Figure 2 Taking mobile phones as an example, in China and Israel, electronic devices are used as a whole. Figure 2 As shown, in addition to the board-level three-dimensional packaging structure 200, the electronic device may also include structures such as a battery 300 and a camera module 400. In one embodiment, the board-level three-dimensional packaging structure 200 is electrically connected to the battery 300, thereby the battery 300 supplies power to the board-level three-dimensional packaging structure 200. The board-level three-dimensional packaging structure 200 can also be electrically connected to the camera module 400, thereby transmitting signals with the camera module 400 to realize functions such as taking pictures and recording videos of the electronic device.

[0048] Figure 3 This is a schematic diagram of a board-level three-dimensional packaging structure 200 in an embodiment of this application, as shown below. Figure 3As shown, in one embodiment, the board-level three-dimensional packaging structure 200 includes a first board 1 and a second board 2 stacked together. The first board 1 may include a first surface 11 and a second surface 12 disposed opposite to each other, with the first surface 11 facing away from the second board 2. The second board 2 may include a third surface 21 and a fourth surface 22 disposed opposite to each other, with the third surface 21 facing the first board 1. The stacking of the first board 1 and the second board 2 results in the second surface 12 and the third surface 21 being adjacent, with the first surface 11 located on the side of the second surface 12 facing away from the second board 2, and the fourth surface 22 located on the side of the third surface 21 facing away from the first board 1. A heat-generating device 4 is disposed on the side of the first board 1 facing away from the second board 2. Specifically, the heat-generating device 4 may be disposed on the first surface 11 of the first board 1. The heat-generating device 4 may be a device with high heat generation, such as a chip; in some embodiments, the heat-generating device 4 may be a system-on-a-chip (SOC). In addition, the board-level three-dimensional packaging structure 200 may also include other electronic devices 5, which may be disposed on the first board 1 or the second board 2. For example, other electronic devices 5 may be disposed on the first surface 11 and the second surface 12 of the first board 1, and other electronic devices 5 may also be disposed on the third surface 21 and the fourth surface 22 of the second board 2.

[0049] Since the devices in the first board 1 and the second board 2 need to be electrically connected, the board-level three-dimensional packaging structure 200 also includes multiple copper pin groups 8. The first board 1 and the second board 2 are connected by the copper pin groups 8, which enable the electrical connection between the devices in the first board 1 and the devices in the second board 2. The space between the first board 1 and the second board 2 is filled with molding compound 9, which encapsulates the copper pin groups 8. Specifically, the copper pin groups 8 are located within the molding compound 9. The ideal situation is that the space between the first board 1 and the second board 2 is filled with molding compound 9. In actual manufacturing, due to factors such as process level, the molding compound 9 between the first board 1 and the second board 2 may contain air bubbles or gaps, or there may be no molding compound in the edge areas, the periphery, or in the structural design of channels within the molding compound 9. Understandably, these situations still constitute the situation where the space between the first board 1 and the second board 2 is filled with molding compound 9.

[0050] In this scheme, the small spacing between the first plate 1 and the second plate 2 allows for the stacking of the first plate 1 and the second plate 2. Specifically, in the prior art, a frame plate is set between the first plate 1 and the second plate 2, with a cavity structure in the middle. It is difficult to manufacture the frame plate too thin, especially when the size of the board-level three-dimensional packaging structure 200 is large, as an excessively thin frame plate can easily cause warping. In this embodiment, the height of the copper pin group 8 can be designed and selected according to actual needs, as long as it is higher than the height of the device on the same side. Specifically, during the fabrication of the board-level three-dimensional packaging structure 200, the copper pin assembly molding compound can be ground. During this process, as long as the grinding does not damage the electronic device on the same side, the height of the copper pin group 8 is also more flexible and can be set lower, which is beneficial for achieving a thinner board-level three-dimensional packaging structure 200. This is beneficial for achieving a thinner board-level three-dimensional packaging structure 200, and thus for achieving a thinner electronic device. The copper pin group 8 has a flexible layout. It can be positioned according to the pin positions on the second surface of the first board 1. Therefore, no additional leads are needed to guide the pins to the frame location, simplifying the complexity of the metal pattern on the second surface of the first board and reducing the area occupied by the metal pattern. The copper pin group 8 has a small diameter, allowing it to connect with smaller pins. Furthermore, when the copper pin group 8 is electrically connected to the first board 1 or the second board 2, less solder 101 is required, and short circuits between adjacent copper pin groups 8 are less likely. Therefore, the copper pin groups 8 can be arranged more densely, and correspondingly, the pins connected to the copper pin groups 8 can be arranged more densely. This facilitates a high-density pin layout connecting the first board 1 and the second board, improving signal transmission density and the integration of the board-level three-dimensional package structure 200. In addition, the copper needle group 8 is connected between the first plate 1 and the second plate 2, which can transfer the heat of the heating device 4 from the first plate 1 to the second plate 2, so that the side of the heating device 4 facing the second plate 2 also has a good heat dissipation capacity, enabling the heating device 4 to achieve double-sided heat dissipation, thereby improving the heat dissipation effect of the heating device 4 and increasing the power density and service life of the heating device 4.

[0051] Furthermore, since the copper pin assembly 8 has a small diameter and therefore weak structural strength, encapsulating it within the molding compound 9 provides better protection, thereby improving the reliability of the connection between the first plate 1 and the second plate 2. Additionally, the molding compound 9, filling the space between the first plate 1 and the second plate 2, also serves to fix the first plate 1 and the second plate 2. This solid structural fixation between the first plate 1 and the second plate 2 enhances their stability and overall strength, making the board-level three-dimensional packaging structure 200 less prone to warping or deformation.

[0052] In this embodiment, both the first plate 1 and the second plate 2 are ultra-thin substrates, which helps to improve the thinness of the board-level three-dimensional packaging structure 200.

[0053] In this embodiment, the diameter of the copper needle assembly 8 can be 0.1 mm to 0.2 mm. Specifically, if the copper needle assembly 8 includes at least one copper needle, then the diameter of the copper needles included in the copper needle assembly 8 is 0.1 mm to 0.2 mm. For example, the diameter of the copper needles in the copper needle assembly 8 can be 0.1 mm, 0.11 mm, 0.12 mm, 0.13 mm, 0.14 mm, 0.15 mm, 0.16 mm, 0.17 mm, 0.18 mm, 0.19 mm, or 0.2 mm, etc. In this scheme, the smaller diameter of the copper needle assembly 8 is beneficial for achieving high-density placement. In some embodiments, the pitch between two adjacent copper needle groups 8 can be 0.2 mm to 0.4 mm. For example, the pitch between two adjacent copper needle groups 8 can be 0.2 mm, 0.22 mm, 0.25 mm, 0.26 mm, 0.28 mm, 0.3 mm, 0.32 mm, 0.35 mm, 0.36 mm, 0.38 mm, or 0.4 mm, etc.

[0054] like Figure 3 As shown, in a specific embodiment, electronic devices 5 can be provided on both the first surface 11 and the second surface 12 of the first plate 1, and electronic devices 5 can be provided on both the first surface 11 and the second surface 12 of the second plate 2, thereby improving the integration of the board-level three-dimensional packaging structure 200.

[0055] like Figure 3As shown, in one embodiment, the plurality of copper needle groups 8 includes a first copper needle group. Specifically, in some embodiments, the plurality of copper needle groups 8 may include one, two, or multiple first copper needle groups. Even in some embodiments, all of the plurality of copper needle groups 8 may be first copper needle groups. The aforementioned first copper needle group includes a first copper needle 81 and a second copper needle 82. The first copper needle 81 is fixedly connected to the first plate 1. Specifically, the second surface 12 of the first plate 1 is connected to the first copper needle 81, that is, the side of the first plate 1 facing the second plate 2 is connected to the first copper needle 81. One end of the first copper needle 81 is connected to the first plate 1, and the other end is connected to the second copper needle 82. The second copper needle 82 is fixedly connected to the second plate 2. Specifically, the third surface 21 of the second plate 2 is connected to the second copper needle 82, that is, the side of the second plate 2 facing the first plate 1 is connected to the second copper needle 82. One end of the second copper needle 82 is connected to the second plate 2, and the other end is connected to the first copper needle 81. The molding compound 9 includes a first molding compound 91 and a second molding compound 92. The first molding compound 91 is fixed to the second surface 12 of the first plate 1. A first copper pin 81 is encapsulated in the first molding compound 91. The first molding compound 91 includes the first copper pin 81, and the end surface of the first copper pin 81 facing away from the first plate 1 is exposed from the surface of the first molding compound 91, thus facilitating connection with the second copper pin 82. The second molding compound 92 is fixed to the third surface 21 of the second plate 2. The second copper pin 82 is encapsulated in the second molding compound 92. The second molding compound 92 covers the second copper pin 82, and the end surface of the second copper pin 82 facing away from the second plate 2 is exposed from the surface of the second molding compound 92, thus facilitating connection with the first copper pin 81. The first molding compound 91 and the second molding compound 92 are fixedly connected, and the first copper pin 81 exposed on the surface of the first molding compound 91 and the second copper pin 82 exposed on the surface of the second molding compound 92 are electrically connected. This scheme allows for the separate fabrication of copper needles 8 and molding compound 9 on the first plate 1 and the second plate 2, simplifying the fabrication process. This is particularly relevant when the second surface 12 of the first plate 1 is provided with electronic devices 5, and the third surface 21 of the second plate 2 is also provided with electronic devices 5. Even when only the second surface 12 of the first plate 1 is provided with electronic devices 5, or only the third surface 21 of the second plate 2 is provided with electronic devices 5, or neither the second surface 12 of the first plate 1 nor the third surface 21 of the second plate 2 is provided with electronic devices 5, the copper needle assembly 8 can still include a single copper needle. In other words, multiple copper needle assemblies can form a row of copper needles on the surface of the first plate 1 or the second plate 2.

[0056] In a specific embodiment, the first molding compound 91 and the second molding compound 92 can be bonded together using non-conductive adhesive 10, and the first copper pin 81 and the second copper pin 82 can be electrically connected using conductive materials, such as bonding with conductive adhesive or soldering with solder 101. This solution simplifies the stacking process of the first plate 1 and the second plate 2 and facilitates the electrical connection of the first copper pin 81 and the second copper pin 82.

[0057] Please continue to refer to this. Figure 3 In one embodiment, the first plate 1 and the second plate 2 are connected by a plurality of copper pin groups 8. At least a portion of the copper pin groups 8 are located directly below the heating element 4. Specifically, the orthographic projection of at least a portion of the copper pin groups 8 onto the first plate 1 lies within the orthographic projection of the heating element 4 onto the first plate 1. Alternatively, if at least a portion of the copper pin groups 8 are located between the heating element 4 and the second plate 2, it facilitates the conduction of heat from the heating element 4 to the second plate 2, thereby improving the heat dissipation efficiency of the heating element 4. The area directly opposite the heating element 4 has a higher heat concentration; therefore, placing copper pin groups 8 in this area helps to specifically enhance the heat dissipation capacity of the heating element 4.

[0058] In an optional embodiment, the copper pin group 8 of the board-level three-dimensional packaging structure 200 may include a functional copper pin group 83, which can be used to transmit electrical signals. For example, the functional copper pin group 83 can be electrically connected to the circuit of the first board 1 to realize the transmission of electrical signals between the devices of the first board 1 and the devices of the second board 2. Specifically, the functional copper pin group 83 is electrically connected to the circuit of the first board 1 and / or the circuit of the second board 2. Then, while transmitting signals, the functional copper pin group 83 can also be used to realize heat transfer.

[0059] In some embodiments, the copper needle assembly 8 may further include a structural copper needle assembly 84. This structural copper needle assembly 84 is not used for transmitting electrical signals but is structurally connected between the first plate 1 and the second plate 2, primarily for heat transfer and structural strength enhancement. Specifically, the structural copper needle assembly 84 is electrically insulated from both the first plate 1 and the second plate 2. In this scheme, in addition to the functional copper needle assembly 83 for signal transmission, the structural copper needle assembly 84 is also provided, which helps improve the heat dissipation efficiency of the heat-generating device 4. In particular, the structural copper needle assembly 84 can be positioned directly below the heat-generating device 4 to specifically enhance its heat dissipation effect. In some embodiments, the structural copper needle assembly 84 and the functional copper needle assembly 83 can be provided according to actual needs; if not needed, they can be omitted.

[0060] Figure 4 This is a schematic diagram of a board-level three-dimensional packaging structure 200 in an embodiment of this application, as shown below. Figure 4As shown, in one embodiment, the first plate 1 includes a first through hole 13 that penetrates the first plate 1. In one embodiment, the first through hole 13 is connected to a copper pin assembly 8, thereby enabling signal transmission between the first surface 11 and the second surface 12 of the first plate 1. Alternatively, the two ends of the first through hole 13 can be connected to the metal patterns of the first surface 11 and the second surface 12 of the first plate 1, respectively, also enabling signal transmission between the first surface 11 and the second surface 12 of the first plate 1. In a specific embodiment, the copper pin assembly 8 connected to the first through hole 13 can be a first copper pin 81, or a functional copper pin assembly 83. The aforementioned first through hole 13 also facilitates the transfer of heat generated by the heating device 4 on the first surface 11 of the first plate 1 to the second surface 12, and then conducted to the second plate 2 via the copper pin assembly 8 for heat dissipation. The inclusion of a metal pillar within the aforementioned first through hole 13 provides better thermal conductivity. Therefore, in addition to transmitting signals, the first through hole 13 can also serve as a heat-conducting structure, that is, the first through hole 13 is not used for transmitting signals, so as to improve the heat dissipation capability of the board-level three-dimensional packaging structure.

[0061] In one specific embodiment, the projection of the first through hole 13 onto the first plate 1 and the projection of the first copper pin 81 onto the first plate 1 at least partially overlap, which is beneficial to improving the heat transfer efficiency and the heat dissipation capability of the board-level three-dimensional packaging structure.

[0062] In some embodiments, the second plate 2 may also be provided with a second through hole 23, which penetrates the second plate 2. In one embodiment, the second through hole 23 is connected to the copper pin assembly 8, thereby enabling signal transmission between the third surface 21 and the fourth surface 22 of the second plate 2. Alternatively, the two ends of the first through hole 13 can be connected to the metal patterns on the first surface 11 and the second surface 12 of the first plate 1, respectively, which can also enable signal transmission between the third surface 21 and the fourth surface 22 of the second plate 2. The aforementioned second through hole 23 can also transfer heat from the third surface 21 of the second plate 2 to the fourth surface 22, thereby facilitating heat conduction to the fourth surface 22 of the second plate 2 and improving the heat dissipation efficiency of the heat-generating device 4. The aforementioned first through hole 13 includes a metal pillar, which has a better thermal conductivity. Therefore, in addition to being used for signal transmission, the aforementioned second through hole 23 can also serve as a heat-conducting structure, that is, the second through hole 23 is not used for signal transmission, in order to improve the heat dissipation capability of the board-level three-dimensional packaging structure.

[0063] In one specific embodiment, the orthographic projection of the second through hole 23 on the second plate 2 and the orthographic projection of the second copper pin 82 on the second plate 2 at least partially overlap, which is beneficial to improving the heat transfer efficiency and the heat dissipation capability of the board-level three-dimensional packaging structure.

[0064] In some embodiments, a metal sheet, metal plate, or heat sink may be provided on the fourth surface 22 of the second plate 2, so that the second through hole 23 can transfer heat to the aforementioned metal sheet, metal plate, or heat sink, thereby further improving the heat dissipation efficiency of the heat-generating device 4. In a specific embodiment, the copper needle group 8 connected to the second through hole 23 can be a second copper needle 82.

[0065] In one embodiment, the board-level three-dimensional packaging structure 200 further includes a heat-sensitive electronic device 5. Specifically, the first board 1 may be provided with a heat-sensitive electronic device 5, the second board 2 may also be provided with a heat-sensitive electronic device 5, or both the first board 1 and the second board 2 may be provided with heat-sensitive electronic devices 5. In short, the heat-sensitive devices included in the board-level three-dimensional packaging structure 200 are staggered from the heat-generating devices 4 to protect the heat-sensitive devices. Specifically, the orthographic projection of the heat-sensitive electronic device 5 onto the first board 1 and the orthographic projection of the heat-generating device 4 onto the first board 1 are staggered, or in other words, the area directly opposite the heat-generating device 4 is not provided with a heat-sensitive electronic device 5, so that the heat-sensitive electronic device 5 is not easily affected by the heat-generating device 4, thereby ensuring the normal operation of the heat-sensitive electronic device 5.

[0066] To enhance the anti-interference capability of the board-level three-dimensional packaging structure 200, a first shielding layer 102 is provided on the side of the first board body 1 and the first molding compound 91, and a second shielding layer 103 is provided on the side of the second board body 2 and the second molding compound 92. The first shielding layer 102 and the second shielding layer 103 are electrically connected. The first shielding layer 102 or the second shielding layer 103 is connected to ground, thereby forming a common ground shielding structure. In a specific embodiment, the first shielding layer 102 and the second shielding layer 103 can be made of metal, and the materials can be the same or different. This provides shielding around the periphery of the board-level three-dimensional packaging structure 200. Specifically, the first shielding layer 102 can be a metal layer forming the surface of the first board body 1 and the first molding compound 91, and the second shielding layer 103 can be a metal layer forming the surface of the second board body 2 and the second molding compound 92. Therefore, the first shielding layer 102 and the second shielding layer 103 occupy less space, which is beneficial to improving the miniaturization of the board-level three-dimensional packaging structure 200.

[0067] Specifically, when implementing the electrical connection between the first shielding layer 102 and the second shielding layer 103, the second molding compound 92 can have a groove 105 on the side facing the first molding compound 91, and the second shielding layer 103 can cover the inner wall of the groove 105, with at least a portion of the conductive adhesive 104 accommodated within the groove 105. In this embodiment, since the conductive adhesive 104 is at least partially accommodated within the groove 105, the conductive adhesive 104 is less likely to fall off, which helps improve the connection reliability of the first shielding layer 102 and the second shielding layer 103.

[0068] In one specific embodiment, the groove 105 of the second molding compound 92 is located outside the edge of the first molding compound 91, or in other words, the groove 105 of the second molding compound 92 is not covered by the first molding compound 91.

[0069] Alternatively, in one embodiment, a conductive adhesive 104 may be connected between the first shielding layer 102 and the second shielding layer 103. To improve the reliability of the conductive adhesive 104 connecting the first shielding layer 102 and the second shielding layer 103, the first molding compound 91 may have a groove 105 on the side facing the second molding compound 92, the first shielding layer 102 covering the inner wall of the groove 105, and at least a portion of the conductive adhesive 104 being accommodated within the groove 105. In this embodiment, since the conductive adhesive 104 is at least partially accommodated within the groove 105, the conductive adhesive 104 is less likely to fall off, which helps to improve the connection reliability of the first shielding layer 102 and the second shielding layer 103.

[0070] In one specific embodiment, the groove 105 of the first molding compound 91 is located outside the edge of the second molding compound 92, or in other words, the groove 105 of the first molding compound 91 is not covered by the second molding compound 92.

[0071] Based on the same technical concept, this application also provides a method for preparing a board-level three-dimensional packaging structure 200, which is used to prepare the board-level three-dimensional packaging structure 200 provided in any of the above embodiments. Figure 5 This is a process flow diagram of one fabrication process of the board-level three-dimensional packaging structure 200 in the embodiments of this application. Figure 6 This is a process flow diagram of one fabrication process of the board-level three-dimensional packaging structure 200 in the embodiments of this application. Figure 7 This is a process flow diagram of a fabrication process for the board-level three-dimensional packaging structure 200 in this application embodiment, as shown below. Figures 5-7 As shown, the fabrication method of the board-level three-dimensional packaging structure 200 in this embodiment includes:

[0072] like Figure 5 The diagram shown is a process flow chart for the fabrication of the first plate.

[0073] Step S101: Attach electronic devices 5 and implant copper pin groups 8 on the second surface 12 of the first plate 1;

[0074] In implementing this step, individual copper needles can be assembled onto the first plate 1 to ensure precise alignment. Alternatively, the frame-type copper needle module can be assembled in one go to improve the fabrication speed of the board-level three-dimensional packaging structure 200. Specifically, the copper needle group 8 in this step may include the first copper needle 81.

[0075] Step S102: The second surface 12 of the first plate is encapsulated to form a first encapsulating material 91;

[0076] The aforementioned first copper needle 81 is located within the first molding compound 91.

[0077] Step S103: Prepare a first metal layer on the side of the first plate 1 and the surface of the first molding compound 91;

[0078] The first metal layer covers the side surface of the first plate 1, the side surface of the first molding compound 91, and the top surface;

[0079] Step S104: Grind the top surface of the first molding compound 91 to remove the first metal layer and expose the surface of the first copper needle 81;

[0080] Step S105: Heat-generating device 4 and electronic device 5 are mounted on the first surface of the first plate 1.

[0081] like Figure 6 The diagram shown is a process flow chart for the fabrication of the first plate.

[0082] Step S201: Attach electronic components 5 to the third surface 21 of the second plate 2 and implant copper pin groups 8;

[0083] In implementing this step, individual copper needles can be assembled onto the second plate to ensure precise alignment. Alternatively, the frame-type copper needle module can be assembled in one go to improve the fabrication speed of the board-level three-dimensional packaging structure 200. Specifically, the copper needle group 8 in this step may include a second copper needle 82.

[0084] Step S202: The third surface 21 of the second plate 2 is encapsulated to form a second encapsulating material 92;

[0085] The aforementioned second copper needle 82 is located within the second molding compound 92.

[0086] Step S203: Prepare a groove 105 on the edge of the side surface of the second molding compound 92 that is away from the second plate body;

[0087] Step S204: Prepare a second metal layer on the side of the second plate 2 and the surface of the second molding compound 92;

[0088] The second metal layer covers the side surface of the second plate 2, the side surface and the top surface of the second molding compound 92. Specifically, the groove 105 of the second molding compound 92 is also covered with the second metal layer.

[0089] Step S205: Grind the top surface of the second molding compound 92 to remove the second metal layer and expose the surface of the second copper pin 82, and place solder 101 on the surface of the second copper pin 82;

[0090] In some embodiments, an electrical connection structure such as conductive adhesive may be placed on the surface of the second copper pin 82. Furthermore, depending on the actual process, an electrical connection structure such as solder 101 or conductive adhesive may also be placed on the surface of the first copper pin 81.

[0091] Step S206: Attach electronic device 5 to the fourth surface 22 of the second plate 2.

[0092] like Figure 7 The diagram shows the process flow chart for the fabrication of the first and second plates.

[0093] Step S301: Stack the first plate formed in step S105 and the second plate formed in step S206, electrically connect the first copper pin 81 and the second copper pin 82, fix the first molding compound 91 and the second molding compound 92, and electrically connect the first shielding layer 102 and the second shielding layer 103.

[0094] Specifically, the first copper needle 81 and the second copper needle 82 can be electrically connected by welding, the first molding compound 91 and the second molding compound 92 can be bonded by non-conductive adhesive 10, and the first shielding layer 102 and the second shielding layer 103 can be electrically connected by conductive adhesive 104, with at least a portion of the conductive adhesive 104 contained in the groove 105.

[0095] The order of steps S101-S105 and S201-S206 is not restricted. Steps S101-S105 can be performed first, followed by steps S201-S206; or steps S201-S206 can be performed first, followed by steps S101-S105. Alternatively, steps S101-S105 and S201-S206 can be performed separately, and then step S301 can be performed at the end for stacking.

[0096] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A board-level three-dimensional packaging structure, characterized in that, It includes a first plate and a second plate stacked together, as well as multiple copper pin groups, heating elements and molding compound; The first plate includes a first surface and a second surface disposed opposite to each other, the first surface being the surface facing away from the second plate, and the heating device being disposed on the first surface; The second plate includes a third surface and a fourth surface disposed opposite to each other; the third surface is the surface facing the first plate. The plurality of copper pin groups are connected between the second surface and the third surface; The space between the second surface and the third surface is filled with a molding compound, which encapsulates the copper needle.

2. The board-level three-dimensional packaging structure as described in claim 1, characterized in that, At least some of the copper needle groups have their orthogonal projections onto the first plate located within the orthogonal projection of the heating element onto the first plate.

3. The board-level three-dimensional packaging structure as described in claim 2, characterized in that, The first plate also includes one or more first through holes, each containing a metal pillar, and the first through hole penetrates the first plate.

4. The board-level three-dimensional packaging structure as described in any one of claims 1 to 3, characterized in that, The plurality of copper needle groups include functional copper needle groups, which are electrically connected to the circuitry of the first board and / or the circuitry of the second board.

5. The board-level three-dimensional packaging structure as described in any one of claims 1 to 3, characterized in that, The plurality of copper needle groups includes structural copper needle groups, which are insulated from the circuit of the first plate and from the circuit of the second plate.

6. The board-level three-dimensional packaging structure as described in claim 4, characterized in that, The plurality of copper needle groups includes structural copper needle groups, which are insulated from the circuit of the first plate and from the circuit of the second plate.

7. The board-level three-dimensional packaging structure as described in any one of claims 1 to 3, characterized in that, The diameter of the copper needle assembly is 0.15mm to 0.2mm.

8. The board-level three-dimensional packaging structure as described in claim 4, characterized in that, The diameter of the copper needle assembly is 0.15mm to 0.2mm.

9. The board-level three-dimensional packaging structure as described in claim 5, characterized in that, The diameter of the copper needle assembly is 0.15mm to 0.2mm.

10. The board-level three-dimensional packaging structure as described in any one of claims 1 to 3, characterized in that, The plurality of copper needle groups includes a first copper needle group, the first copper needle group includes a first copper needle and a second copper needle, and the molding compound includes a first molding compound and a second molding compound. The first copper needle is connected to the second surface of the first plate, the first molding compound is fixed to the second surface of the first plate, and the first molding compound wraps around the first copper needle; The second copper needle is connected to the third surface of the second plate, the second molding compound is fixed to the third surface of the second plate, and the second molding compound wraps around the second copper needle; The first molding compound and the second molding compound are fixedly connected, and the first copper pin and the second copper pin are electrically connected.

11. The board-level three-dimensional packaging structure as described in claim 4, characterized in that, The plurality of copper needle groups includes a first copper needle group, the first copper needle group includes a first copper needle and a second copper needle, and the molding compound includes a first molding compound and a second molding compound. The first copper needle is connected to the second surface of the first plate, the first molding compound is fixed to the second surface of the first plate, and the first molding compound wraps around the first copper needle; The second copper needle is connected to the third surface of the second plate, the second molding compound is fixed to the third surface of the second plate, and the second molding compound wraps around the second copper needle; The first molding compound and the second molding compound are fixedly connected, and the first copper pin and the second copper pin are electrically connected.

12. The board-level three-dimensional packaging structure as described in claim 5, characterized in that, The plurality of copper needle groups includes a first copper needle group, the first copper needle group includes a first copper needle and a second copper needle, and the molding compound includes a first molding compound and a second molding compound. The first copper needle is connected to the second surface of the first plate, the first molding compound is fixed to the second surface of the first plate, and the first molding compound wraps around the first copper needle; The second copper needle is connected to the third surface of the second plate, the second molding compound is fixed to the third surface of the second plate, and the second molding compound wraps around the second copper needle; The first molding compound and the second molding compound are fixedly connected, and the first copper pin and the second copper pin are electrically connected.

13. The board-level three-dimensional packaging structure as described in claim 7, characterized in that, The plurality of copper needle groups includes a first copper needle group, the first copper needle group includes a first copper needle and a second copper needle, and the molding compound includes a first molding compound and a second molding compound. The first copper needle is connected to the second surface of the first plate, the first molding compound is fixed to the second surface of the first plate, and the first molding compound wraps around the first copper needle; The second copper needle is connected to the third surface of the second plate, the second molding compound is fixed to the third surface of the second plate, and the second molding compound wraps around the second copper needle; The first molding compound and the second molding compound are fixedly connected, and the first copper pin and the second copper pin are electrically connected.

14. The board-level three-dimensional packaging structure as described in claim 10, characterized in that, A non-conductive adhesive is used to connect the first molding compound and the second molding compound, and a solder or conductive adhesive is used to connect the first copper needle and the second copper needle.

15. The board-level three-dimensional packaging structure as described in claim 10, characterized in that, A first shielding layer is provided on the side of the first plate and the first molding compound, and a second shielding layer is provided on the side of the second plate and the second molding compound. The first shielding layer and the second shielding layer are electrically connected.

16. The board-level three-dimensional packaging structure as described in claim 14, characterized in that, A first shielding layer is provided on the side of the first plate and the first molding compound, and a second shielding layer is provided on the side of the second plate and the second molding compound. The first shielding layer and the second shielding layer are electrically connected.

17. The board-level three-dimensional packaging structure as described in claim 15, characterized in that, A conductive adhesive is connected between the first shielding layer and the second shielding layer; The first molding compound has a groove on the side facing the second molding compound, the first shielding layer covers the inner wall of the groove, and at least a portion of the conductive adhesive is contained within the groove; Alternatively, the second molding compound has a groove on the side facing the first molding compound, the second shielding layer covers the inner wall of the groove, and at least a portion of the conductive adhesive is contained within the groove.

18. The board-level three-dimensional packaging structure as described in claim 16, characterized in that, A conductive adhesive is connected between the first shielding layer and the second shielding layer; The first molding compound has a groove on the side facing the second molding compound, the first shielding layer covers the inner wall of the groove, and at least a portion of the conductive adhesive is contained within the groove; Alternatively, the second molding compound has a groove on the side facing the first molding compound, the second shielding layer covers the inner wall of the groove, and at least a portion of the conductive adhesive is contained within the groove.

19. The board-level three-dimensional packaging structure as described in any one of claims 1 to 3, characterized in that, The second plate includes a second through hole, and the second through hole contains a metal pillar, and the second through hole penetrates the second plate.

20. The board-level three-dimensional packaging structure as described in claim 4, characterized in that, The second plate includes a second through hole, and the second through hole contains a metal pillar, and the second through hole penetrates the second plate.

21. The board-level three-dimensional packaging structure as described in claim 5, characterized in that, The second plate includes a second through hole, and the second through hole contains a metal pillar, and the second through hole penetrates the second plate.

22. The board-level three-dimensional packaging structure as described in claim 7, characterized in that, The second plate includes a second through hole, and the second through hole contains a metal pillar, and the second through hole penetrates the second plate.

23. The board-level three-dimensional packaging structure as described in claim 10, characterized in that, The second plate includes a second through hole, and the second through hole contains a metal pillar, and the second through hole penetrates the second plate.

24. The board-level three-dimensional packaging structure as described in claim 14, characterized in that, The second plate includes a second through hole, and the second through hole contains a metal pillar, and the second through hole penetrates the second plate.

25. The board-level three-dimensional packaging structure as described in claim 15, characterized in that, The second plate includes a second through hole, and the second through hole contains a metal pillar, and the second through hole penetrates the second plate.

26. The board-level three-dimensional packaging structure as described in claim 17, characterized in that, The second plate includes a second through hole, and the second through hole contains a metal pillar, and the second through hole penetrates the second plate.

27. An electronic device, characterized in that, It includes a housing and a board-level three-dimensional packaging structure as described in any one of claims 1 to 26, wherein the board-level three-dimensional packaging structure is disposed on the housing.

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