Packaging structure
By adopting a stacked package structure in the 2.5D packaging technology, the bending outer ends are used to realize the electrical connection of the high-density lead frame, the problem of insufficient interconnection density of the lead frame in the prior art is solved, and multi-chip stacking and higher packaging integration are achieved.
Patent Information
- Application Number
- CN202421295537.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-06
- Publication Date
- 2025-03-14
- Estimated Expiration
- 2034-06-06
AI Technical Summary
In the existing 2.5D packaging technology, the interconnect density of the lead frame is low, resulting in less application in packaging, which cannot meet the higher packaging unit integration requirements and expansion of application scenarios.
Using a stacked package structure, including a first lead frame assembly and a second lead frame assembly, electrically connects through the bent outer ends of the third and fourth pins to form a high-density lead frame, thereby realizing multi-chip stacking.
Multi-chip stacking is realized, meeting more packaging unit integration needs and application scenarios, and simplifying the stacking packaging process.
Smart Images
Figure CN222619757U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of semiconductors, in particular to a packaging structure. Background Art
[0002] With the rapid development of the semiconductor industry, a new design method of chiplet technology has emerged, which packages small chips with different functions together to form a heterogeneous integrated chip packaging structure. As the input and output density of chips increases, the number of chips integrated in a single package increases significantly. The existing 2.5D packaging technology is to package multiple small chips into one package as a multi-chip packaging solution to connect adjacent chip pads in a single package to improve its packaging integration.
[0003] However, the existing 2.5D packaging is mainly based on the packaging on the substrate, and the lead frame is less used in 2.5D packaging due to its low interconnection density. Therefore, how to increase the integration of lead frame-based packaging to meet more packaging unit integration requirements and the expansion of application scenarios is a technical problem that needs to be solved urgently. Utility Model Content
[0004] In view of the above problems, the utility model proposes a packaging structure.
[0005] The technical solution adopted by the utility model is as follows:
[0006] A packaging structure includes a first lead frame component, a second lead frame component and a package body, wherein the first lead frame component and the second lead frame component are stacked:
[0007] The first lead frame assembly includes a first lead frame and a first chip mounted face-up or flip-down on the front of the first lead frame, wherein the first lead frame has a first pin and a second pin;
[0008] The second lead frame assembly comprises a second lead frame and a second chip which is mounted face-up or face-down on the front of the second lead frame, the second lead frame has a third pin and a fourth pin, the third pin has a first outer end bent toward one side of the first lead frame, the fourth pin has a second outer end bent toward one side of the first lead frame, the first outer end is located in a gap between different pins of the first lead frame; the second outer end is stacked on the second pin, and the fourth pin is electrically connected to the second pin;
[0009] The package body covers the first lead frame assembly and the second lead frame assembly.
[0010] The package body of the present application has a first surface and a second surface arranged opposite to each other, the lower surface of the first pin is exposed on the first surface of the package body, or the lower surface of the first pin and the lower surface of the second pin are exposed on the first surface of the package body.
[0011] The third pin of the present application includes a first outer end portion bent toward one side of the first lead frame, a first inner end portion close to the second chip, and a first connecting portion connecting the first outer end portion and the first inner end portion.
[0012] The fourth pin of the present application includes a second outer end portion bent toward one side of the first lead frame, a second inner end portion close to the second chip, and a second connecting portion connecting the second outer end portion and the second inner end portion.
[0013] In the present application, the lower surface of the first outer end portion of the third pin is exposed at the first surface of the package body.
[0014] In the present application, the upper surface of the first inner end of the third pin and the upper surface of the second inner end of the fourth pin are exposed on the second surface of the package body.
[0015] The second lead frame of the present application further has a fifth pin which is not bent toward one side of the first lead frame.
[0016] The upper surface of the fifth pin of the present application is exposed on the second surface.
[0017] The first chip of the present application is mounted on the front side of the first lead frame, and the first chip is connected to the first pin and the second pin through leads.
[0018] The first chip of the present application is flip-mounted on the front side of the first lead frame.
[0019] The second chip of the present application is mounted on the front side of the second lead frame, and the second chip is electrically connected to the first inner end of the third pin and the second inner end connected to the fourth pin through leads.
[0020] The second chip of the present application is mounted on the front side of the second lead frame, and the second chip is electrically connected to the first inner end of the third pin, the second inner end of the fourth pin, and the fifth pin through leads.
[0021] The second chip of the present application is flip-mounted on the front side of the second lead frame.
[0022] The front side of the first lead frame of the present application is arranged opposite to the front side of the second lead frame, or the front side of the first lead frame is arranged opposite to the back side of the second lead frame.
[0023] The outer end of the second pin of the present application has a limiting groove, and the second outer end of the fourth pin has a protrusion, and the protrusion is embedded in the limiting groove;
[0024] Alternatively, the outer end of the second pin has a protrusion, the second outer end of the fourth pin has a limiting groove, and the protrusion is embedded in the limiting groove.
[0025] The beneficial effects of the utility model are:
[0026] A packaging structure in one of the aforementioned embodiments of the present application includes a first lead frame assembly, a second lead frame assembly and a packaging body, wherein the first lead frame assembly and the second lead frame assembly are stacked: the first lead frame assembly includes a first lead frame and a first chip mounted face-up or flip-mounted on the front side of the first lead frame, the first lead frame having a first pin and a second pin; the second lead frame assembly includes a second lead frame and a second chip mounted face-up or flip-mounted on the front side of the second lead frame, the second lead frame having a third pin and a fourth pin, the third pin and the fourth pin are both bent toward one side of the first lead frame, and the outer end of the third pin is located in the gap between different pins of the first lead frame; the outer end of the fourth pin is stacked on the second pin, and the fourth pin is electrically connected to the second pin; the packaging body covers the first lead frame assembly and the second lead frame assembly. The outer end of the third pin of the second lead frame of the present application is located in the gap between different pins of the first lead frame, and the outer end of the fourth pin of the second lead frame is stacked on the second pin of the first lead frame, and the fourth pin is electrically connected to the second pin. The present application can realize the stacking of multiple chips to meet more packaging unit integration requirements and the expansion of application scenarios; the packaging structure of the present application can realize the separate processing of the first lead frame component and the second lead frame component, and then perform bonding and plastic sealing in the plastic sealing mold, that is, the structure of the present application can simplify the stacking packaging process. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Figure 1 is a top view of the first lead frame assembly of Example 1;
[0028] Figure 2 is a bottom view of the second lead frame assembly of Example 1;
[0029] Figure 3 is a bottom view of the packaging structure of Example 1;
[0030] Figure 4 yes Figure 3 A1-A1 cross-sectional view;
[0031] Figure 5 yes Figure 3 Middle B1-B1 cross-sectional view;
[0032] Figure 6 yes Figure 3 Middle C1-C1 cross-sectional view;
[0033] Figure 7 is a bottom view of the second lead frame assembly of Example 2;
[0034] Figure 8 is a bottom view of the packaging structure of Example 2;
[0035] Fig. 9 yes Figure 8 A2-A2 cross-sectional view;
[0036] Fig.10 yes Figure 8 B2-B2 cross-sectional view;
[0037] Fig.11 yes Figure 8 Middle C2-C2 cross-sectional view;
[0038] Fig.12 is a bottom view of the packaging structure of Example 3;
[0039] Fig.13 yes Fig.12 A3-A3 cross-sectional view;
[0040] Fig.14 yes Fig.12 B3-B3 cross-sectional view;
[0041] Fig.15 yes Fig.12 Middle C3-C3 cross-sectional view;
[0042] Fig.16 is a bottom view of the packaging structure of Example 4;
[0043] Fig.17 yes Fig.16 A4-A4 cross-sectional view;
[0044] Fig.18 yes Fig.16 Middle B4-B4 cross-sectional view;
[0045] Fig.19 yes Fig.16 Schematic diagram of C4-C4 cross-section.
[0046] The reference numerals in the figures are:
[0047] 1. First lead frame assembly; 11. First lead frame; 110. First base island; 111. First pin; 112. Second pin; 1121. Limiting groove; 12. First chip; 13. Lead; 14. Solder ball; 2. Second lead frame assembly; 21. Second lead frame; 210. Second base island; 211. Third pin; 212. Fourth pin; 2121. Protrusion; 213. Fifth pin; 211a. First outer end; 211b. First inner end; 211c. First connecting portion; 212a. Second outer end; 212b. Second inner end; 212c. Second connecting portion; 22. Second chip; 3. Package body; 31. First side; 32. Second side. DETAILED DESCRIPTION
[0048] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.
[0049] In the description of this application, it should be noted that the terms "inside", "outside", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the application is usually placed when in use, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.
[0050] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0051] The utility model is described in detail below in conjunction with the accompanying drawings.
[0052] Example 1
[0053] This embodiment discloses a packaging structure. Figure 1 , 2 , 3, 4, 5 and 6 ( Figure 1 is a top view of the first lead frame assembly of Example 1; Figure 2is a bottom view of the second lead frame assembly of Example 1; Figure 3 is a bottom view of the packaging structure of Example 1; Figure 4 yes Figure 3 A1-A1 cross-sectional view; Figure 5 yes Figure 3 Middle B1-B1 cross-sectional view; Figure 6 yes Figure 3 The C1-C1 cross-sectional schematic diagram includes: a first lead frame assembly 1, a second lead frame assembly 2 and a package body 3, and the first lead frame assembly 1 and the second lead frame assembly 2 are stacked:
[0054] The first lead frame assembly 1 includes a first lead frame 11 and a first chip 12 disposed on the front surface of the first lead frame 11 , wherein the first lead frame 11 has a first lead 111 and a second lead 112 ;
[0055] The second lead frame assembly 2 includes a second lead frame 21 and a second chip 22 disposed on the front of the second lead frame 21. The second lead frame 21 has a third pin 211 and a fourth pin 212. The third pin 211 has a first outer end 211a bent toward the first lead frame 11. The fourth pin 212 has a second outer end 212a bent toward the first lead frame 11. The first outer end 211a is located in a gap between different pins of the first lead frame 11. The second outer end 212a is stacked on the second pin 112. The fourth pin 212 is electrically connected to the second pin 112.
[0056] The package body 3 covers the first lead frame assembly 1 and the second lead frame assembly 2 .
[0057] The third pin 211 of the present application includes a first outer end 211a bent toward one side of the first lead frame 11, a first inner end 211b close to the second chip 22, and a first connecting portion 211c connecting the first outer end 211a and the first inner end 211b.
[0058] The fourth pin 212 of the present application includes a second outer end 212a bent toward one side of the first lead frame 11, a second inner end 212b close to the second chip 22, and a second connecting portion 212c connecting the second outer end 212a and the second inner end 212b.
[0059] The first connection portion 211c and the second connection portion 212c may be in various shapes. In this embodiment, the first connection portion 211c and the second connection portion 212c are inclined straight lines.
[0060] The first outer end portion 211a of the third pin 211 of the second lead frame 21 of the present application is located in the gap between different pins of the first lead frame 11, and the second outer end portion 212a of the fourth pin 212 of the second lead frame 21 is stacked on the second pin 112 of the first lead frame 11, and the fourth pin 212 is electrically connected to the second pin 112. The present application can realize the stacking of multiple chips by stacking lead frames to meet more packaging unit integration requirements and the expansion of application scenarios.
[0061] The packaging structure of the present application can realize the separate processing of the first lead frame assembly 1 and the second lead frame assembly 2, and then perform bonding and plastic sealing in a plastic sealing mold, that is, the structure of the present application can simplify the stacking packaging process. In the specific operation, before forming the package body 3, when the first lead frame assembly 1 and the second lead frame assembly 2 are bonded, the first outer end portion 211a of the third pin 211 of the second lead frame assembly 2 is placed in the gap between different pins of the first lead frame assembly 1, and the second outer end portion 212a of the fourth pin 212 in the second lead frame assembly 2 is mounted on the upper surface of the second pin 112 in the first lead frame assembly 1, so that the second lead frame assembly 2 can be simply and stably installed above the first lead frame assembly 1, thereby improving the integration of the formed packaging structure, and then a plastic encapsulation process is performed to form the package body 3 (it should be noted that before the two components are secured, the first chip 12 is first mounted on the first lead frame 11, so that the first chip 12 is electrically connected to the corresponding first pin 111 and the second pin 112, and the second chip 22 is mounted on the second lead frame 21, so that the second chip 22 is electrically connected to the corresponding third pin 211 and the fourth pin 212).
[0062] In this application, “the first outer end 211a of the third pin 211 is located in the gap between different pins of the first lead frame 11” means that the first outer end 211a of the third pin 211 can be located between two first pins 111, between two second pins 12, or between the first pin and the second pin. In one embodiment, the first outer end 211a of the third pin 211 can be located in the same plane as the first pin 111 and the second pin 112.
[0063] The number and type of the first chip 12 mentioned in the present application are not limited, that is, there can be multiple chips, and the multiple chips can be divided into multiple types; the number and type of the second chip 22 mentioned in the present application are not limited, that is, there can be multiple chips, and the multiple chips can be divided into multiple types, including but not limited to signal processing chips, logic control chips, storage chips, sensor chips, power chips or radio frequency chips.
[0064] The stacking arrangement of the first lead frame assembly 1 and the second lead frame assembly 2 mentioned in the present application refers to that one assembly is stacked on top of another assembly.
[0065] The front side of the lead frame in this application refers to the side used for mounting the chip.
[0066] In actual use, the package body 3 may not expose the second pin 112 , that is, the package body 3 exposes the first pin 111 and the third pin 211 , and the electrical signal of the second pin 112 may be led out from the upper surface of the package body 3 through the second inner end 212 b of the fourth pin 212 .
[0067] like Figure 1 and 4 As shown, in this embodiment, the first chip 12 is mounted on the front side of the first lead frame 11 , and the first chip 12 is connected to the first pin 111 and the second pin 112 through the lead wire 13 .
[0068] In actual use, the first chip 12 can also be flip-mounted on the front side of the first lead frame 11. For example, it can be flip-mounted on the front side of the first lead frame 11 through solder balls. The flip-mounting of the first chip 12 can reduce the thickness of the package structure.
[0069] like Figure 4 , 5 As described in Figure 6, in this embodiment, the package body 3 has a first surface 31 and a second surface 32 that are arranged opposite to each other, and the front surface of the first lead frame 11 is arranged opposite to the front surface of the second lead frame 21. The back surface of the first lead frame 11 and the lower surface of the first outer end 211a of the third lead 211 are exposed on the first surface 31 of the package body 3, and the upper surface of the first inner end 211b of the third lead 211 and the upper surface of the second inner end 212b of the fourth lead 212 are exposed on the second surface 32 of the package body 3.
[0070] The portion of each pin exposed from the package body can be used as a terminal connected to the outside (PCB board, other package structures or devices), so that the package structure of the present application can be applied to 2.5D packaging or 3D packaging.
[0071] In the existing structure, the heat dissipation channel is relatively simple. In the present application, the front side of the first lead frame 11 is arranged opposite to the front side of the second lead frame 21, and heat is dissipated from both the front and back sides (the first side 31 and the second side 32) of the package body 3 at the same time, which can improve the heat dissipation capacity of the entire package.
[0072] like Figure 5 As shown, in this embodiment, the second chip 22 is mounted on the front side of the second lead frame 21 , and the second chip 22 is connected to the third pin 211 and the fourth pin 212 through the lead wire 13 .
[0073] like Figure 1 , 2As shown in FIG. 4 , in this embodiment, the outer end portion of the second pin 112 has a limiting groove 1121 , and the second outer end portion 212a of the fourth pin 212 has a protrusion 2121 , and when the first lead frame assembly 1 and the second lead frame assembly 2 are attached, the protrusion 2121 is embedded in the limiting groove 1121 .
[0074] The limiting groove 1121 and the protruding portion 2121 cooperate with each other to achieve reliable positioning. After the first lead frame assembly 1 and the second lead frame assembly 2 are processed respectively, they can be quickly and reliably assembled and sealed in the plastic sealing mold.
[0075] In actual use, it can also be configured as follows: the outer end of the second pin 112 has a protrusion 2121 , the second outer end 212 a of the fourth pin 212 has a limiting groove 1121 , and the protrusion 2121 is embedded in the limiting groove 1121 .
[0076] like Figure 4 , 5 As shown in Figures 6 and 7, the first lead frame 11 may further include a first base island 110, a first pin 111 and a second pin 112 are located around the first base island 110, and the first pin 111 and the second pin 112 are isolated from the first base island 110 by the package body 3. The upper surface of the first base island 110 is used to attach the first chip 12. In a specific embodiment, the first chip 12 includes a relative back side and an active side, the active side has a pad electrically connected to the integrated circuit in the first chip 12, the back side of the first chip 12 is attached to the upper surface of the first base island 110 by an adhesive, and the pad on the active side of the first chip 12 is electrically connected to the corresponding first pin 111 and the second pin 112 through the lead 13. In actual use, the first chip 12 can also be flipped: the first chip 12 includes a relative back side and an active side, the active side has a first welding protrusion electrically connected to the integrated circuit in the first chip 12, and when the active side of the first chip 12 is flipped downward on the upper surface of the corresponding first pin 111 and the second pin 112, the first welding protrusion on the active surface of the first chip 12 is welded together with the upper surface of the corresponding first pin 111 and the second pin 112.
[0077] like Figure 4 , 5As shown in Figures 6 and 7, the second lead frame 21 also has a second base island 210, and the third pin 211 and the fourth pin 212 are located around the second base island 210. The third pin 211 and the fourth pin 212 are isolated from the second base island 210 by the package body 3. The lower surface of the second base island 210 is used to attach the second chip 22. In a specific embodiment, the second chip 22 includes a relative back side and an active side, and the active side has a pad electrically connected to the integrated circuit in the second chip 22. The back side of the second chip 22 is attached to the lower surface of the second base island 210 by an adhesive, and the pad on the active surface of the second chip 22 is electrically connected to the lower surface of the corresponding third pin 211 and the fourth pin 212 through the lead 13. Specifically, the pad on the active surface of the second chip 22 is electrically connected to the lower surface of the first inner end 211b of the corresponding third pin 211 and the lower surface of the second inner end 212b of the fourth pin 212 through the lead 13.
[0078] In this embodiment, the first pin 111 , the second pin 112 , the third pin 211 , and the fourth pin 212 are made of conductive metal.
[0079] The material of the package body 3 is resin. In one embodiment, the material of the package body 3 is epoxy resin, polyimide resin, benzocyclobutene resin or polybenzoxazole resin containing fillers; or it can also be polybutylene terephthalate, polycarbonate, polyethylene terephthalate, polyethylene, polypropylene, polyolefin, polyurethane, polyolefin, polyether sulfone, polyamide, polyurethane, ethylene-vinyl acetate copolymer or polyvinyl alcohol containing fillers. The filler can be an inorganic filler or an organic filler.
[0080] Example 2
[0081] This embodiment discloses a packaging structure. Figure 7 , 8 , 9, 10 and 11, among which, Figure 7 is a bottom view of the second lead frame assembly of Example 2; Figure 8 is a bottom view of the packaging structure of Example 2; Fig. 9 yes Figure 8 A2-A2 cross-sectional view; Fig.10 yes Figure 8 B2-B2 cross-sectional view; Fig.11 yes Figure 8 Schematic diagram of the C2-C2 cross-section.
[0082] The difference between this embodiment and the first embodiment is that the second lead frame 21 further has a fifth pin 213 that is not bent toward the first lead frame 11, and the fifth pin 213 is exposed from the upper surface (the second surface 32) of the package body 3. The portion of the fifth pin 213 exposed from the package body can be used as a terminal connected to the outside (PCB board, other package structures or devices), and this arrangement can achieve the expansion of more application scenarios. Specifically, Fig. 9 and 11 As shown, the package body 3 has a first surface 31 and a second surface 32 arranged opposite to each other, the back surface of the first lead frame 11 and the lower surface of the first outer end portion 211a of the third pin 211 are exposed on the first surface 31, and the upper surface of the first inner end portion 211b of the third pin 211, the upper surface of the second inner end portion 212b of the fourth pin 212 and the upper surface of the fifth pin 213 are exposed on the second surface 32.
[0083] In this embodiment, the second chip 22 is mounted on the front side of the second lead frame 21 , and the second chip 22 is connected to the third pin 211 , the fourth pin 212 , and the fifth pin 213 through the lead wires 13 .
[0084] In this embodiment, the fifth pin 213 is made of conductive metal.
[0085] like Fig. 9 , 10 As shown in FIG. 11 , the second lead frame 21 further has a second base island 210 , and the third pin 211 , the fourth pin 212 and the fifth pin 213 are located around the second base island 210 , and the third pin 211 , the fourth pin 212 and the fifth pin 213 are isolated from the second base island 210 by the package body 3 .
[0086] In actual use, the first chip 12 of this embodiment can also be flipped: the first chip 12 includes a relative back side and an active side, the active side has a first welding protrusion electrically connected to the integrated circuit in the first chip 12, and when the active side of the first chip 12 is flipped downward on the upper surface of the corresponding first pin 111 and the second pin 112, the first welding protrusion on the active surface of the first chip 12 is welded together with the upper surface of the corresponding first pin 111 and the second pin 112.
[0087] Example 3
[0088] This embodiment discloses a packaging structure. Fig.12 , 13 , 14 and 15, among which, Fig.12 is a bottom view of the packaging structure of Example 3; Fig.13 yes Fig.12 A3-A3 cross-sectional view; Fig.14 yes Fig.12 B3-B3 cross-sectional view; Fig.15 yes Fig.12 Schematic diagram of the C3-C3 cross-section.
[0089] The difference between this embodiment and the first embodiment is that the second chip 22 is flip-mounted on the front of the second lead frame 21 through the solder ball 14. The second lead frame 21 does not have a base island, and the second chip 22 is connected to the corresponding third pin 211 and the fourth pin 212 by flip-chip connection to reduce the thickness of the integrated inductor packaging structure. Specifically, the second chip 22 includes a relative back surface and an active surface, and the active surface has a second welding protrusion electrically connected to the integrated circuit in the second chip 22. When the active surface of the second chip 22 is flip-mounted upward on the lower surface of the corresponding third pin 211 and the fourth pin 212, the second welding protrusion on the active surface of the second chip 22 is welded together with the corresponding third pin 211 and the fourth pin 212. Specifically, the second welding protrusion on the active surface of the second chip 22 is welded together with the lower surface of the first inner end 211b of the corresponding third pin 211 and the lower surface of the second inner end 212b of the fourth pin 212.
[0090] In actual use, the fifth pin 213 involved in Embodiment 2 may also be provided in this embodiment. In this case, the second chip 22 is electrically connected to the fifth pin 213 via the second welding protrusion.
[0091] In actual use, the first chip 12 of this embodiment can also be flipped: the first chip 12 includes a relative back side and an active side, the active side has a first welding protrusion electrically connected to the integrated circuit in the first chip 12, and when the active side of the first chip 12 is flipped downward on the upper surface of the corresponding first pin 111 and the second pin 112, the first welding protrusion on the active surface of the first chip 12 is welded together with the upper surface of the corresponding first pin 111 and the second pin 112.
[0092] Example 4
[0093] This embodiment discloses a packaging structure. Fig.16 , 17 , 18 and 19, among which, Fig.16 is a bottom view of the packaging structure of Example 4; Fig.17 yes Fig.16 A4-A4 cross-sectional view; Fig.18 yes Fig.16 Middle B4-B4 cross-sectional view; Fig.19 yes Fig.16 Schematic diagram of C4-C4 cross-section.
[0094] The difference between this embodiment and the first embodiment is that the front surface of the first lead frame 11 and the back surface of the second lead frame 21 are arranged opposite to each other.
[0095] In this embodiment, the second chip 22 is mounted on the front side of the second lead frame 21 .
[0096] In this embodiment, the package body 3 has a first surface 31 and a second surface 32 that are relatively arranged. The back surface of the first lead frame 11 and the lower surface of the first outer end portion 211a of the third pin 211 are exposed on the first surface 31 of the package body 3, and the first inner end portion 211b of the third pin 211 and the second inner end portion 212b of the fourth pin 212 are no longer exposed on the package body 3.
[0097] In actual use, the second chip 22 may also be flip-mounted on the front side of the second lead frame 21 .
[0098] In actual use, the first chip 12 may also be flip-mounted on the front side of the first lead frame 11 .
[0099] In actual use, the fifth pin 213 involved in the second embodiment may also be provided in this embodiment.
[0100] The above description is only a preferred embodiment of the utility model, and does not limit the patent protection scope of the utility model. Any equivalent structural transformation made using the contents of the utility model specification and drawings, directly or indirectly used in other related technical fields, is also included in the protection scope of the utility model.
Claims
1. A packaging structure, characterized in that: The invention comprises a first lead frame component, a second lead frame component and a package body, wherein the first lead frame component and the second lead frame component are stacked and arranged: The first lead frame assembly includes a first lead frame and a first chip mounted face-up or flip-down on the front of the first lead frame, wherein the first lead frame has a first pin and a second pin; The second lead frame assembly includes a second lead frame and a second chip which is mounted face-up or flip-down on the front of the second lead frame, the second lead frame has a third pin and a fourth pin, the third pin has a first outer end bent toward one side of the first lead frame, the fourth pin has a second outer end bent toward one side of the first lead frame, the first outer end is located in a gap between different pins of the first lead frame, the second outer end is stacked on the second pin, and the fourth pin is electrically connected to the second pin; The package body covers the first lead frame assembly and the second lead frame assembly.
2. The packaging structure according to claim 1, characterized in that: The package body has a first surface and a second surface arranged opposite to each other, the lower surface of the first pin is exposed on the first surface of the package body, or the lower surface of the first pin and the lower surface of the second pin are exposed on the first surface of the package body.
3. The packaging structure according to claim 2, characterized in that: The third pin includes a first outer end portion bent toward the first lead frame, a first inner end portion close to the second chip, and a first connecting portion connecting the first outer end portion and the first inner end portion; the fourth pin includes a second outer end portion bent toward the first lead frame, a second inner end portion close to the second chip, and a second connecting portion connecting the second outer end portion and the second inner end portion.
4. The packaging structure according to claim 3, characterized in that: The lower surface of the first outer end portion of the third pin is exposed from the first surface of the package body.
5. The packaging structure according to claim 3, characterized in that: An upper surface of a first inner end portion of the third lead and an upper surface of a second inner end portion of the fourth lead are exposed on the second surface of the package body.
6. The packaging structure according to claim 3, characterized in that: An upper surface of the first inner end portion of the third pin and an upper surface of the second inner end portion of the fourth pin are not exposed from the second surface of the package body.
7. The packaging structure according to claim 2, characterized in that: The second lead frame further has a fifth lead which is not bent toward one side of the first lead frame.
8. The packaging structure according to claim 7, characterized in that: The upper surface of the fifth pin is exposed on the second surface.
9. The packaging structure according to claim 1, characterized in that: The first chip is mounted on the front side of the first lead frame, and the first chip is connected to the first pin and the second pin through leads.
10. The packaging structure according to claim 1, wherein: The first chip is flip-mounted on the front side of the first lead frame.
11. The packaging structure according to claim 1, characterized in that: The second chip is mounted on the front side of the second lead frame, and the second chip is connected to the third pin and the fourth pin through leads.
12. The packaging structure according to claim 7, characterized in that: The second chip is mounted on the front side of the second lead frame, and the second chip is connected to the third pin, the fourth pin and the fifth pin through leads.
13. The packaging structure according to claim 1, characterized in that: The second chip is flip-mounted on the front side of the second lead frame.
14. The packaging structure according to claim 1, wherein: The front side of the first lead frame is arranged opposite to the front side of the second lead frame, or the front side of the first lead frame is arranged opposite to the back side of the second lead frame.
15. The packaging structure according to claim 1, characterized in that: The outer end of the second pin has a limiting groove, and the second outer end of the fourth pin has a protrusion, and the protrusion is embedded in the limiting groove; Alternatively, the outer end of the second pin has a protrusion, the second outer end of the fourth pin has a limiting groove, and the protrusion is embedded in the limiting groove.