Chip package structure
By setting riveting components and mechanical interlocking of molding compound on the heat dissipation substrate, the problem of separation between molding compound and heat dissipation substrate is solved, enhancing the electrical connection stability and service life of chip packaging structure.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHENZHEN WEST CHUANGXIN INFORMATION TECH CO LTD
- Filing Date
- 2025-08-28
- Publication Date
- 2026-07-31
AI Technical Summary
In existing packaging structures, there is a lack of effective means of fixing the molding compound to the heat dissipation substrate, which leads to the separation of the molding compound from the heat dissipation substrate under thermal stress, damaging the electrical connection between the chip and the lead frame.
Rivets are installed on the heat dissipation substrate to fix the pad frame, thereby enhancing the connection strength between the heat dissipation substrate and the pad frame. A mechanical interlock is formed between the molding compound and the rivets to ensure stable electrical connection.
It effectively prevents the molding compound from separating from the heat dissipation substrate, ensuring the stability of the electrical connection between the chip and the pad frame, and extending the lifespan of the chip package.
Smart Images
Figure CN224583755U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of chip packaging technology, and in particular to a chip packaging structure. Background Technology
[0002] Semiconductor device packaging involves fixing chips, cut from wafers, onto a heat sink substrate and electrically connecting the chip to a lead frame. A molding compound is then used to encapsulate both the chip and the lead frame, preventing damage from harsh external environments while maintaining electrical connectivity between the chip and external circuits. However, current packaging structures rely solely on the adhesion between the molding compound and the heat sink substrate after curing. Due to a lack of more effective fixing methods, thermal stress can cause the molding compound and the heat sink substrate to separate, disrupting the electrical connection between the chip and the lead frame. Summary of the Invention
[0003] In view of this, this application proposes a chip packaging structure, including: a chip, a heat sink substrate, a pad frame, a riveting component, and a molding compound; The rivets are positioned opposite each other on the heat sink substrate, and the two rivets are located on the same side of the heat sink substrate. The pad frame is positioned on the rivets. The chip is mounted on the heat sink substrate and located between two rivets, and the chip is electrically connected to the pad frame. The molding compound encapsulates the riveting components and pad frame, and fills the space between the heat sink substrate and the pad frame. The molding compound has a reinforcing part that fits tightly against the sidewall of the heat sink substrate.
[0004] In one possible implementation, the riveting component includes: a fixing part and a riveting post; The fixing part is set on the heat sink substrate, the pad frame is erected on the fixing part, and the riveting post passes through the pad frame, the fixing part and the heat sink substrate in sequence.
[0005] In one possible implementation, the fixing part is integrally formed with the heat sink substrate.
[0006] In one possible implementation, the riveted post includes a necked section and an enlarged head; The enlarged head is fixedly connected to the necked section, and the enlarged head is located at the end of the necked section away from the heat sink substrate; The diameter of the constricted section is smaller than the inner diameter of the fixed part, and the diameter of the enlarged head is larger than the inner diameter of the fixed part.
[0007] In one possible implementation, internal leads are also included; the chip is electrically connected to the pad frame via the internal leads.
[0008] In one possible implementation, lugs are provided on opposite sides of the heat sink substrate.
[0009] In one possible implementation, an adhesive layer is also included; the adhesive layer is disposed between the chip and the heat sink substrate.
[0010] In one possible implementation, both the molding compound and the reinforcing parts are made of epoxy resin.
[0011] Beneficial effects of this application This application uses rivets on the heat sink substrate to fix the pad frame, which enhances the connection strength between the heat sink substrate and the pad frame. When the chip package structure is subjected to thermal stress, the rivets can effectively prevent the molding compound from separating from the heat sink substrate, thereby ensuring the stability and reliability of the electrical connection between the chip and the pad frame, reducing the abnormality or interruption of the electrical connection between the two due to the separation of the molding compound and the heat sink substrate, and extending the service life of the chip package.
[0012] Other features and aspects of this application will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description
[0013] The accompanying drawings, which are included in and form part of this specification, illustrate exemplary embodiments, features, and aspects of this application together with the specification and serve to explain the principles of this application.
[0014] Figure 1 A bottom view of the chip package structure according to an embodiment of this application is shown; Figure 2 Show Figure 1 A sectional view of AA; Figure 3 Show Figure 1 A cross-sectional view of BB; Figure 4 This diagram illustrates the main structure of the heat sink substrate according to an embodiment of this application. Figure 5 A top view showing the chip package structure according to an embodiment of this application is provided. Detailed Implementation
[0015] Various exemplary embodiments, features, and aspects of this application will now be described in detail with reference to the accompanying drawings. The same reference numerals in the drawings denote elements that have the same or similar functions. Although various aspects of the embodiments are shown in the drawings, they are not necessarily drawn to scale unless specifically indicated otherwise.
[0016] It should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model or simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.
[0017] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.
[0018] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments.
[0019] Furthermore, to better illustrate this application, numerous specific details are provided in the following detailed embodiments. Those skilled in the art should understand that this application can be implemented without certain specific details. In some instances, methods, means, components, and circuits well-known to those skilled in the art have not been described in detail in order to highlight the main points of this application.
[0020] This application proposes a chip packaging structure, such as Figures 1 to 5 As shown, the device includes a chip 100, a heat sink substrate 200, a pad frame 300, a rivet 400, and a molding compound 500. The rivets 400 are disposed opposite each other on the heat sink substrate 200, and the two rivets 400 are located on the same side of the heat sink substrate 200. The pad frame 300 is disposed on the rivets 400. The chip 100 is disposed on the heat sink substrate 200 and is located between the two rivets 400. The chip 100 is electrically connected to the pad frame 300. The molding compound 500 is disposed to enclose the rivets 400 and the pad frame 300, and fills the space between the heat sink substrate 200 and the pad frame 300. The molding compound 500 is provided with a reinforcing part 510, which is tightly fitted to the sidewall of the heat sink substrate 200.
[0021] It should be noted that the heat sink substrate 200 is used to provide support for the overall structure. The riveting pieces 400 are fixedly mounted on the heat sink substrate 200. The two oppositely arranged riveting pieces 400 form symmetrical support, so that the pad frame 300 and the heat sink substrate 200 always maintain a stable relative position, avoiding the electrical connection between the chip 100 and the pad frame 300 due to stress deformation, and enhancing the connection strength between the heat sink substrate 200 and the pad frame 300. The pad frame 300 is used to realize the electrical connection between the chip 100 and the external circuit. The chip 100 is fixedly mounted on the heat sink substrate 200 and electrically connected to the pad frame 300. The pad frame 300 conducts the electrical signal / current of the chip 100 to the external circuit, thereby realizing the electrical connection between the chip 100 and the external circuit. At the same time, the heat generated by the chip 100 during operation is quickly conducted away by the rapid heat conduction characteristics of the heat sink substrate 200, ensuring that the chip 100 operates at a suitable temperature.
[0022] Molding compound 500 is suitable for sealing and fixing pad frame 300, rivet 400, and chip 100. The assembled structure of chip 100, heat sink substrate 200, and pad frame 300 is placed into an injection mold. Molding compound 500 is injected into the mold cavity through an injection molding process. Molding compound 500 fully fills the gap between heat sink substrate 200 and pad frame 300, and evenly covers rivet 400, pad frame 300, and chip 100. The design of molding compound 500 filling the gap between heat sink substrate 200 and pad frame 300 and wrapping rivet 400 ensures... The molding compound 500 and the riveting member 400 form a mechanical interlock, which significantly enhances the connection strength between the molding compound 500 and the heat sink substrate 200. This prevents the electrical connection between the chip 100 and the pad frame 300 from being damaged due to separation caused by thermal stress between the molding compound 500 and the heat sink substrate 200, thus ensuring the stability of the electrical connection between the chip 100 and the pad frame 300. The reinforcing part 510 is suitable for increasing the contact area and bonding force between the molding compound 500 and the heat sink substrate 200, thereby further enhancing the connection strength between the molding compound 500 and the heat sink substrate 200.
[0023] Chip 100 is electrically connected to external circuits via pad frame 300. Signals are transmitted between chip 100 and external circuits. Heat generated during chip 100 operation is quickly dissipated through heat sink substrate 200. This application uses rivets 400 on heat sink substrate 200 to fix pad frame 300, which enhances the connection strength between heat sink substrate 200 and pad frame 300. When the chip 100 package structure is subjected to thermal stress, rivets 400 can effectively prevent separation between molding compound 500 and heat sink substrate 200, thereby ensuring the stable and reliable electrical connection between chip 100 and pad frame 300, reducing the risk of abnormal or interrupted electrical connection due to separation of molding compound 500 and heat sink substrate 200, and extending the service life of chip 100 package.
[0024] In one possible implementation, the heat sink substrate 200 is made of a high thermal conductivity material, thereby enabling the heat sink substrate 200 to effectively expand the natural convection heat dissipation area to increase heat dissipation and further accelerate the reduction of the temperature of the chip 100.
[0025] Preferably, the heat sink substrate 200 is made of either metallic copper or a high thermal conductivity alloy.
[0026] In one possible implementation, such as Figure 3 , Figure 4 As shown, the riveting component 400 includes: a fixing part 410 and a riveting post 420; the fixing part 410 is disposed on the heat sink substrate 200, the pad frame 300 is erected on the fixing part 410, and the riveting post 420 passes through the pad frame 300 and the fixing part 410 in sequence to be riveted to the heat sink substrate 200.
[0027] It should be noted that the fixing part 410 is used to provide a support reference for the pad frame 300, ensuring that the pad frame 300 is stably mounted on the heat sink substrate 200. The main body of the fixing part 410 is a hollow columnar structure, and the hollow hole of the fixing part 410 is correspondingly set with the riveting point of the heat sink substrate 200. The hollow structure of the fixing part 410 provides a preset through channel for the riveting post 420, so that the riveting post 420 can pass through the fixing part 410 axially without additional drilling during assembly. While avoiding assembly errors caused by misalignment during assembly of the rivet post 420, the verticality of the rivet post 420 is constrained by the inner wall of the fixing part 410, ensuring the relative position of the pad frame 300 and the heat sink substrate 200. The rivet post 420 is suitable for locking the pad frame 300, the fixing part 410, and the heat sink substrate 200 into one unit, thereby effectively resisting the relative displacement between the three caused by thermal stress, vibration, etc., and ensuring the connection stability between the pad frame 300 and the heat sink substrate 200.
[0028] Furthermore, the fixing part 410 is provided with a preset height so that a preset gap is maintained between the pad frame 300 and the heat sink substrate 200. The design of the preset gap avoids interference between the heat sink substrate 200 and the pad frame 300, thereby allowing the shape of the heat sink substrate 200 to be adjusted according to actual needs. That is, the shape of the heat sink substrate 200 can be flexibly designed according to actual heat dissipation or assembly requirements. The value range of the preset height is 0.25mm-0.5mm.
[0029] Preferably, the preset height is 0.4mm.
[0030] In one possible implementation, the fixing part 410 is integrally formed with the heat sink substrate 200. The integral forming design improves the connection strength between the fixing part 410 and the heat sink substrate 200, and avoids the pad frame 300 from tilting due to the deformation of the fixing part 410 alone, thereby protecting the electrical connection between the chip 100 and the pad frame 300. In actual production, the fixing part 410 can be manufactured by stamping, casting or other processes on the heat sink substrate 200, and corresponding mounting holes can be reserved on the heat sink substrate 200. Then, the riveting post 420 can be fixed on the heat sink substrate 200 by riveting process.
[0031] In one possible implementation, the rivet post 420 includes a necked section and an enlarged head; the enlarged head is fixedly connected to the necked section and is located at one end of the necked section away from the heat sink substrate 200; the diameter of the necked section is smaller than the inner diameter of the fixing part 410, and the diameter of the enlarged head is larger than the inner diameter of the fixing part 410.
[0032] It should be noted that the enlarged head is fixedly located at one end of the necked section. The end of the necked section opposite to the enlarged head passes through the pad frame 300, the fixing part 410, and the heat sink substrate 200 in sequence for riveting. The diameter of the necked section is slightly smaller than the inner diameter of the fixing part 410, allowing the riveting post 420 to easily pass through the hollow hole of the fixing part 410 and be riveted to the heat sink substrate 200. Operators do not need to spend too much effort aligning or forcibly inserting the riveting post 420, reducing assembly time and improving overall production efficiency. After the riveting post 420 is riveted to the heat sink substrate 200, the enlarged head, because its diameter is larger than the inner diameter of the fixing part 410, cooperates with the fixing part 410 to fix the pad frame 300, preventing the pad frame 300 from shifting or falling off the riveting part 400. This ensures that the heat sink substrate 200, the riveting part 400, and the pad frame 300 always maintain a preset relative position, ultimately ensuring the stability of the overall packaging structure.
[0033] In one possible implementation, an inner lead 610 is also included; the chip 100 is electrically connected to the pad frame 300 via the inner lead 610; there are two or more inner leads 610, which are spaced apart circumferentially along the chip 100.
[0034] In one possible implementation, lugs 210 are provided on opposite sides of the heat sink substrate 200. It should be noted that the lugs 210 are disposed adjacent to the rivet 400, and the molding compound 500 is fixedly mounted on the lugs 210. The sidewalls of the lugs 210 adjacent to the heat sink substrate 200 are tightly fitted with the reinforcing portion 510. The lugs 210 provide additional fixing points for the molding compound 500, increasing the connection area and strength between the molding compound 500 and the heat sink substrate 200, further preventing separation between the molding compound 500 and the heat sink substrate 200. The tight fit between the lugs 210 and the reinforcing portion 510 further enhances the sealing performance of the packaging structure.
[0035] Furthermore, the lug 210 is integrally formed with the heat sink substrate 200.
[0036] In one possible implementation, an adhesive layer is also included; the adhesive layer is disposed between the chip 100 and the heat sink substrate 200; it should be noted that the adhesive layer provides a firm adhesion base for the chip 100, ensuring that the chip 100 maintains a stable position on the heat sink substrate 200; and enhancing the fixation stability of the chip 100 on the heat sink substrate 200.
[0037] Furthermore, the adhesive layer is made of any of the following materials: solder, eutectic material, or conductive adhesive.
[0038] In one possible implementation, the molding compound 500 is made of epoxy resin.
[0039] The various embodiments of this application have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.
Claims
1. A chip package structure, characterized by, include: Chips, heat sink substrates, pad frames, rivets, and molding compounds; The rivet members are disposed opposite each other on the heat sink substrate, and the two rivet members are located on the same side of the heat sink substrate. The pad frame is disposed on the rivet members. The chip is disposed on the heat sink substrate and located between the two riveting members, and the chip is electrically connected to the pad frame; The molding compound encapsulates the rivet and the pad frame, and fills the space between the heat sink substrate and the pad frame. The molding compound has a reinforcing part that is tightly fitted to the sidewall of the heat sink substrate.
2. The chip package structure of claim 1, wherein, The riveting component includes: a fixing part and a riveting post; The fixing part is disposed on the heat sink substrate, the pad frame is erected on the fixing part, and the riveting post passes through the pad frame and the fixing part in sequence and is riveted to the heat sink substrate.
3. The chip package structure of claim 2, wherein, The fixing part is integrally formed with the heat sink substrate.
4. The chip package structure of claim 2, wherein, The riveting post includes a necked section and an enlarged head; The enlarged head is fixedly connected to the necked section, and the enlarged head is located at the end of the necked section away from the heat sink substrate. The diameter of the constricted section is smaller than the inner diameter of the fixing part, and the diameter of the enlarged head is larger than the inner diameter of the fixing part.
5. The chip package structure of claim 1, wherein, It also includes the inner lead wire; The chip is electrically connected to the pad frame via the internal leads.
6. The chip package structure of claim 1, wherein, The heat sink substrate has lugs on opposite sides.
7. The chip package structure of claim 1, wherein, It also includes the adhesive layer; The adhesive layer is disposed between the chip and the heat sink substrate.
8. The chip package structure of claim 1, wherein, Both the molding compound and the reinforcing part are made of epoxy resin.