Packaging structure capable of preventing glue overflow and enhancing heat dissipation

Abstract

The utility model discloses a packaging structure capable of preventing glue overflow and enhancing heat dissipation, which comprises a lead frame and a chip, the peripheries of the lead frame and the chip are coated with a plastic package body, the lead frame comprises a base island and pins, the chip is arranged on the base island through glue, the chip is electrically connected with the pins and / or the base island through leads, and the pins are arranged on the lead frame. The base island is provided with a gluing area and an anti-overflow glue groove, the anti-overflow glue groove is located at the periphery of the gluing area, the chip is provided with a boss corresponding to the anti-overflow glue groove, and the boss is embedded into the anti-overflow glue groove during assembly; according to the technical scheme of the utility model, the anti-overflow glue groove is formed in the periphery of the gluing area, and the boss corresponding to the anti-overflow glue groove is arranged on the chip, so that the glue climbs and extends towards the anti-overflow glue groove along the gluing area and enters the anti-overflow glue groove during gluing, and the problem of glue overflow is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of chip packaging, and particularly relates to a packaging structure for preventing glue overflow and enhancing heat dissipation. Background Art

[0002] As Figure 1 shown, in a common semiconductor packaging structure, the chip is flatly placed on the base island through glue bonding, and then electrically connected to the pins through leads, or the chip is electrically connected to the pins and the base island through leads. Since the glue is fluid, a certain safe distance needs to be maintained between the edge of the chip and the edge of the base island, otherwise the glue will overflow outside the base island and fall onto the back of the frame. When there are solder joints on the base island and the sufficient distance is not maintained, the glue may spread and submerge the solder joints, and there will also be a problem that the glue creeps onto the chip surface. Content of the Utility Model

[0003] Aiming at the deficiencies of the existing technology, the utility model provides a packaging structure for preventing glue overflow and enhancing heat dissipation. By providing an anti-glue-overflow groove between the glue application area and the wiring area, and providing a boss corresponding to the anti-glue-overflow groove on the chip, when bonding, the glue creeps along the glue application area towards the anti-glue-overflow groove and enters the anti-glue-overflow groove, thus avoiding the problem of glue overflow.

[0004] To achieve the above object, the utility model adopts the following technical solutions:

[0005] A packaging structure for preventing glue overflow and enhancing heat dissipation, comprising a lead frame and a chip. The lead frame and the chip are coated with a plastic package. The lead frame includes a base island and pins. The chip is disposed on the base island through glue. The chip is electrically connected to the pins and / or the base island through leads. The base island is provided with a glue application area and an anti-glue-overflow groove. The anti-glue-overflow groove is located outside the glue application area. The chip is provided with a boss corresponding to the anti-glue-overflow groove. During assembly, the boss is embedded in the anti-glue-overflow groove. By providing an anti-glue-overflow groove outside the glue application area and a boss corresponding to the anti-glue-overflow groove on the chip, when bonding, the glue creeps along the glue application area towards the anti-glue-overflow groove and enters the anti-glue-overflow groove, thus avoiding the problem of glue overflow.

[0006] As a preferred solution, a first groove is formed on the lower side of one end of the base island close to the pins, and a second groove is formed on the lower side of one end of the pins close to the base island.

[0007] As a preferred solution, the first groove and the second groove form a convex-shaped through groove between the base island and the pins, and the plastic package is filled into the convex-shaped through groove.

[0008] As a preferred solution, the distance from the anti-glue-overflow groove to the edge of the base island is 150μm - 5000μm.

[0009] As a preferred solution, the depth of the anti-glue overflow groove is 1 / 3-2 / 3 of the thickness of the lead frame.

[0010] As a preferred solution, the depth of the anti-overflow glue groove is adapted to the height of the boss.

[0011] As a preferred solution, the shape of the anti-overflow glue groove is a straight bar, staggered straight bars, curved bars, a ring or a combination of the above shapes, and the boss is adapted to the shape of the anti-overflow glue groove.

[0012] As a preferred solution, the width of the anti-overflow glue groove is 100 μm-400 μm.

[0013] As a preferred solution, the base island is further provided with a wiring area, and the anti-overflow glue groove is located between the glue coating area and the wiring area.

[0014] Compared with the prior art, the utility model has obvious advantages and beneficial effects. Specifically, by opening an anti-overflow glue groove on the periphery of the glue coating area and providing a boss corresponding to the anti-overflow glue groove on the chip, during gluing, the glue climbs along the glue coating area to the anti-overflow glue groove and enters the anti-overflow glue groove, thereby avoiding glue overflow, reducing the difficulty of assembly, and improving the assembly efficiency of the product. At the same time, the distance between the edge of the chip and the edge of the base island can be designed to be smaller, thereby obtaining a smaller product size. Moreover, since the boss is designed on the edge of the chip and other areas of the chip are recessed, the chip thickness is thinner, which is more conducive to heat conduction, the available arc height space is larger, and the heat dissipation efficiency is more effectively improved.

[0015] In order to more clearly illustrate the structural features, technical means and specific purposes and functions achieved by the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments: BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a cross-sectional schematic diagram of a common packaging structure in the prior art;

[0017] Figure 2 It is a cross-sectional schematic diagram of Example 1 of the present utility model;

[0018] Figure 3 This is a schematic cross-sectional exploded structural diagram of Example 1 of the present utility model;

[0019] Figure 4 It is a cross-sectional schematic diagram of embodiment 2 of the present utility model.

[0020] Description of the accompanying drawings:

[0021] 10-lead frame; 11-base island; 12-glue coating area;

[0022] 13-wiring area; 14-first groove; 15-anti-overflow glue groove;

[0023] 16 - lead; 20 - chip; 21 - boss;

[0024] 30 - pin; 31 - second groove; 40 - convex - shaped through - slot;

[0025] 50 - plastic package body. Detailed implementation mode

[0026] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the utility model and simplifying the description, rather than indicating or implying that the indicated position or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present utility model.

[0027] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "connection" 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 mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0028] As Figures 2-4 shown, the present utility model discloses a packaging structure for preventing glue overflow and enhancing heat dissipation, including a lead frame 10 and a chip 20. The lead frame 10 and the chip 20 are surrounded by a plastic package body 50. The lead frame 10 includes a base island 11 and pins 30. The chip 20 is disposed on the base island 11 through glue. The chip 20 is electrically connected to the pins 30 through leads 16. The base island 11 is provided with a glue - applying area 12 and an anti - glue - overflow groove 15. The anti - glue - overflow groove 15 is located outside the glue - applying area 12. The chip 20 is provided with a boss 21 corresponding to the anti - glue - overflow groove 15. During assembly, the boss 21 is embedded in the anti - glue - overflow groove 15. By providing the anti - glue - overflow groove 15 outside the glue - applying area 12 and the boss 21 corresponding to the anti - glue - overflow groove 15 on the chip 20, when gluing, the glue creeps along the glue - applying area 12 towards the anti - glue - overflow groove 15 and enters the anti - glue - overflow groove 15, avoiding the problem of glue overflow.

[0029] As Figure 4 shown, the chip 20 can also be electrically connected to the pins 30 and the base island 11 through leads 16.

[0030] One side of the base island 11 near one end of the pin 30 has a first groove 14, and one side of the pin 30 near one end of the base island 11 has a second groove 31; the first groove 14 and the second groove 31 form a convex-shaped through groove 40 between the base island 11 and the pin 30, and the encapsulant 50 is filled into the convex-shaped through groove 40. Through the convex-shaped through groove 40, the encapsulant 50 can be fixed on the pin 30 and the base island 11 after shaping, avoiding the shedding of the encapsulant 50 and improving the quality of the product.

[0031] The distance from the anti-overflow glue groove to the edge of the base island is 150μm - 5000μm.

[0032] It should be understood that the distance from the anti-overflow glue groove to the edge of the base island can be changed according to the actual situation, and the minimum distance should be greater than or equal to 150μm.

[0033] The depth of the anti-overflow glue groove is 1 / 3 - 2 / 3 of the thickness of the lead frame.

[0034] The depth of the anti-overflow glue groove 15 is adapted to the height of the boss 21.

[0035] The shape of the anti-overflow glue groove 15 is a straight bar, a staggered straight bar, a curved bar, a ring or a combination of the above figures, and the boss 21 is adapted to the shape of the anti-overflow glue groove 15.

[0036] It should be understood that according to the actual situation, the shape of the anti-overflow glue groove 15 can also be a staggered straight bar, a curved bar, a ring or a combination of the above figures. In short, there are no excessive restrictions on the shapes of the anti-overflow glue groove 15 and the boss 21.

[0037] The width of the anti-overflow glue groove is 100μm - 400μm.

[0038] It should be understood that the width of the anti-overflow glue groove can be changed according to the actual situation, and the minimum distance should be greater than or equal to 100μm.

[0039] The base island 11 is also provided with a wiring area 13, and the anti-overflow glue groove 15 is located between the glue application area 12 and the wiring area 13; by setting the anti-overflow glue groove 15 between the glue application area 12 and the wiring area 13, the wiring area 13 can be prevented from being flooded by glue.

[0040] The usage method of the present utility model: Apply glue to the glue application area 12, then align the boss 21 of the chip 20 with the anti-overflow glue groove 15. The glue is extruded by the chip 20 and the base island 11 and crawls towards the anti-overflow glue groove 15 until it enters the anti-overflow glue groove 15. After electrically connecting the chip 20 and the pin 30 with the lead 16, use the encapsulant 50 to wrap and protect the lead frame 10 and the chip 20 to complete the encapsulation.

[0041] In summary, in the present utility model, an anti-glue overflow groove 15 is provided around the glue application area 12, and a boss 21 corresponding to the anti-glue overflow groove 15 is provided on the chip 20. When bonding, the glue crawls along the glue application area 12 towards the anti-glue overflow groove 15 and enters the anti-glue overflow groove 15, preventing the glue from overflowing, reducing the assembly difficulty, improving the assembly efficiency of the product. At the same time, the distance between the edge of the chip 20 and the edge of the base island 11 can be designed to be smaller, obtaining a smaller product size. Moreover, due to the design of the boss 21 at the edge of the chip 20 and the depression of other areas of the chip 20, the thickness of the chip 20 is thinner, which is more conducive to heat conduction, and the available arc height space is larger, more effectively improving the heat dissipation efficiency.

[0042] The above are only the preferred embodiments of the present utility model and are not intended to limit the present utility model. Therefore, any modifications, equivalent replacements, improvements, etc. made to the above embodiments according to the actual technology of the present utility model still fall within the scope of the technical solution of the present utility model.

Claims

1. An encapsulation structure for preventing glue overflow and enhancing heat dissipation, comprising a lead frame and a chip. The lead frame and the periphery of the chip are coated with a plastic package. The lead frame includes a base island and pins. The chip is disposed on the base island through glue, and the chip is electrically connected to the pins and / or the base island through leads. It is characterized in that: The base island is provided with a glue application area and an anti-overflow glue groove. The anti-overflow glue groove is located outside the glue application area. The chip is provided with a boss corresponding to the anti-overflow glue groove. During assembly, the boss is embedded into the anti-overflow glue groove.

2. The encapsulation structure for preventing glue overflow and enhancing heat dissipation according to claim 1, wherein The lower side of the base island near one end of the lead has a first groove, and the lower side of the lead near the base island has a second groove.

3. The encapsulation structure for preventing overflow of glue and enhancing heat dissipation according to claim 2, characterized in that, The first groove and the second groove form a convex-shaped through groove between the base island and the lead, and the encapsulant is filled into the convex-shaped through groove.

4. The encapsulation structure for preventing glue overflow and enhancing heat dissipation according to claim 3, wherein, The distance from the anti-overflow glue groove to the edge of the base island is 150μm - 5000μm.

5. The encapsulation structure for preventing overflow of glue and enhancing heat dissipation according to claim 1, characterized in that, The depth of the anti-overflow glue groove is 1 / 3 - 2 / 3 of the thickness of the lead frame.

6. The encapsulation structure for preventing glue overflow and enhancing heat dissipation according to claim 1, characterized in that The depth of the anti-overflow glue groove is adapted to the height of the boss.

7. A spill-proof and heat dissipation-enhanced packaging structure according to claim 1, characterized in that, The shape of the anti-overflow glue groove is a straight strip, an intersecting straight strip, a curved strip, a ring, or a combination of the above figures, and the boss is adapted to the shape of the anti-overflow glue groove.

8. A glue overflow prevention and heat dissipation enhancement packaging structure according to claim 1, characterized in that, The width of the anti-overflow glue groove is 100μm - 400μm.

9. A spill-proof glue and enhanced heat dissipation packaging structure according to claim 1, wherein The base island is further provided with a wiring area, and the anti-overflow glue groove is located between the glue application area and the wiring area.

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