Package structure for preventing deformation of pin bonding

Abstract

This utility model discloses a packaging structure to prevent pin bonding deformation, including a frame, a heat sink, and at least one chip. The heat sink is mounted on the frame, and the chip is attached to the upper surface of the heat sink. The frame has several pins, one end of which has a solder joint located above the heat sink. The plane of the solder joint is parallel to the plane of the heat sink, and a gap is formed between the solder joint and the heat sink. At least one support block is provided in the gap. The lower end face of the support block is bonded to the heat sink, and the upper end face of the support block abuts against the solder joint. The solder joint is soldered to the chip via a lead. The support block is a bare silicon block with a cuboid structure. This utility model supports the solder joint on the pins with the support block on the heat sink, preventing the solder joint from being suspended and preventing it from sinking and deforming during bonding, thus ensuring good soldering.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor packaging technology, specifically to a packaging structure that prevents pin bonding deformation. Background Technology

[0002] Currently, in some semiconductor device packaging structures, in order to reduce the package size, one end of the pin extends above the heat sink, and there is a height difference between the pin and the heat sink to ensure the insulation requirements of the two. By bonding, the two ends of the lead are soldered to the pin and the chip respectively using a wrench (the chip is mounted on the heat sink).

[0003] However, since the pins are suspended above the heatsink, when the bonding tool presses down on the suspended end of the pin, it can easily cause the pin to sink and deform, resulting in poor soldering. At the same time, the sinking of the pin will reduce the distance between the pin and the heatsink, reduce the product's withstand voltage, and affect the product's function. Utility Model Content

[0004] This invention addresses the shortcomings of existing technologies by providing a packaging structure that prevents pin bonding deformation. It uses a support block on a heat sink to support the solder joint on the pin, preventing the solder joint from being suspended in the air. During bonding, it can prevent the solder joint from sinking and deforming, ensuring a good weld.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A packaging structure for preventing pin bonding deformation includes a frame, a heat sink, and at least one chip. The heat sink is mounted on the frame, and the chip is attached to the upper surface of the heat sink. The frame has a plurality of pins, one end of each pin having a solder joint. The solder joint is located above the heat sink, and the plane of the solder joint is parallel to the plane of the heat sink. A gap is formed between the solder joint and the heat sink, and at least one insulating support block is provided in the gap. The lower end face of the support block is bonded to the heat sink, and the upper end face of the support block abuts against the solder joint. The solder joint is soldered to the chip via a lead.

[0007] By placing a support block in the gap between the welded part and the heat sink, the lower end of the support block is bonded to the heat sink, and the upper end of the support block abuts against the welded part. The support block supports the welded part on the pin, preventing the welded part from being suspended in the air. During bonding, it can prevent the welded part from sinking and deforming, ensuring good welding.

[0008] In one embodiment, the support block is a silicon block or a ceramic block.

[0009] In one embodiment, the silicon block is a bare silicon block formed by dicing a raw wafer.

[0010] In one embodiment, the support block is a cuboid structure.

[0011] In one embodiment, the length L1 of the support block is 0.75mm to 0.85mm, and the width b of the support block is 0.55mm to 0.65mm.

[0012] In one embodiment, the height h of the support block is 0.3 mm to 0.4 mm.

[0013] In one embodiment, a plurality of support blocks are provided in the gap, and the plurality of support blocks are spaced apart along the extension direction of the gap, and an injection flow channel is formed between two adjacent support blocks.

[0014] In one embodiment, the length L2 of the injection runner is not less than the length L1 of the support block.

[0015] In one embodiment, the heat sink is riveted, welded, glued, or screwed to the frame.

[0016] In one embodiment, several of the pins are distributed on the front and rear sides of the frame, and the chip is located between two opposite pins.

[0017] Compared with the prior art, this utility model has obvious advantages and beneficial effects. Specifically, by setting a support block in the gap formed between the welding part and the heat sink, the lower end face of the support block is bonded to the heat sink, and the upper end face of the support block abuts against the welding part. The support block supports the welding part on the pin, preventing the welding part from being suspended. During bonding, it can prevent the welding part from sinking and deforming, ensuring good welding.

[0018] To more clearly illustrate the structural features, technical means, and specific objectives and functions achieved by this utility model, the following detailed description is provided in conjunction with the accompanying drawings and specific embodiments: Attached Figure Description

[0019] Figure 1 This is a structural schematic diagram of an embodiment of the present utility model;

[0020] Figure 2 yes Figure 1 Schematic diagram of the cross section of AA;

[0021] Figure 3 yes Figure 1 A schematic diagram of the cross-section of BB.

[0022] Explanation of reference numerals in the attached diagram:

[0023] 10-Frame, 11-Heat sink, 12-Chip, 13-Pin, 131-Soldering part, 14-Gap, 15-Support block, 16-Lead wire, 17-Injection channel. Detailed Implementation

[0024] In the description of this utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., 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 the utility model and simplifying the description, and do not indicate or imply that the position 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.

[0025] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0026] like Figure 1-3 As shown, this utility model discloses a packaging structure to prevent pin bonding deformation, including a frame 10, a heat sink 11, and at least one chip 12. The heat sink 11 is mounted on the frame 10, and the chip 12 is attached to the upper surface of the heat sink 11.

[0027] The frame 10 has a plurality of pins 13, one end of each pin 13 having a solder joint 131. The solder joint 131 is located above the heat sink 11, and the plane of the solder joint 131 is parallel to the plane of the heat sink 11. A gap 14 is formed between the solder joint 131 and the heat sink 11. At least one insulating support block 15 is provided in the gap 14. The lower end face of the support block 15 is bonded to the heat sink 11, and the upper end face of the support block 15 abuts against the solder joint 131. The solder joint 131 is soldered to the chip 12 via a lead wire 16.

[0028] The support block 15 is a silicon block or a ceramic block; by using a silicon block, the silicon material in the molding compound has a better bonding effect with the silicon block during plastic encapsulation, making the product less prone to delamination.

[0029] The silicon block is a bare silicon block, which is formed by cutting a raw wafer. The raw wafer is a wafer without circuitry on its surface, and the wafer material is monocrystalline silicon. By using a bare silicon block, the required bare silicon block can be processed by cutting the raw wafer using existing mature grinding and scribing equipment, which is easy to produce and has low cost. At the same time, the bare silicon block can also be bonded to the heat sink 11 using existing mature wafer mounting technology. The process is simple and reliable, with high production efficiency. Subsequently, the heat sink 11 is installed on the frame 10 so that the bare silicon block abuts against the welding part 131.

[0030] The support block 15 has a cuboid structure; the cuboid structure of the support block 15 provides a large contact area with the heat sink 11 and the welding part 131, resulting in more stable support and better support effect.

[0031] The length L1 of the support block 15 is 0.75mm to 0.85mm, and the width b of the support block 15 is 0.55mm to 0.65mm.

[0032] The height h of the support block 15 is 0.3mm to 0.4mm. By using a support block 15 with a height h of 0.3mm to 0.4mm, the distance between the welded part 131 and the heat sink 11 is not less than 0.3mm, ensuring that the product has a high pressure resistance value.

[0033] The gap 14 extends in the left-right direction, and a plurality of support blocks 15 are provided in the gap 14. The plurality of support blocks 15 are distributed at intervals along the extension direction of the gap 14. For example, the number of support blocks 15 in the gap 14 is three, and an injection channel 17 is formed between two adjacent support blocks 15. By setting the injection channel 17, during plastic encapsulation, the plastic encapsulation material can flow smoothly and fill the area between the welding part 131, the support block 15 and the heat sink 11, avoiding product delamination.

[0034] The length L2 of the injection channel 17 is not less than the length L1 of the support block 15; by setting the length L2 of the injection channel 17 to be not less than the length L1 of the support block 15, the molding material can flow smoothly and the product delamination effect is better.

[0035] The heat sink 11 is riveted, welded, glued or screwed to the frame 10. In this utility model, the heat sink 11 is preferably riveted to the frame 10.

[0036] Several pins 13 are distributed on the front and rear sides of the frame 10, and the chip 12 is located between two front and rear opposite pins 13. For example, two chips 12 are provided between two front and rear opposite pins 13.

[0037] The production process of this utility model:

[0038] First, the required size of the support block 15 is cut out from the original wafer using a grinding and scribing equipment;

[0039] Second, attach the support block 15 to the corresponding position on a heat dissipation strip;

[0040] Third, the heat dissipation strip is cut into multiple independent heat dissipation fins 11;

[0041] Fourth, rivet the heat sink 11 body to the frame 10 so that the upper end face of the support block 15 abuts and fits against the lower surface of the welding part 131.

[0042] Fifth, solder the two ends of the lead 16 to the chip 12 and the soldering part 131 respectively, and solder two adjacent chips 12 through the lead 16;

[0043] Sixth, semiconductor products can be obtained through plastic encapsulation.

[0044] In summary, this utility model provides a support block 15 by placing it in the gap 14 formed between the welding part 131 and the heat sink 11. The lower end face of the support block 15 is bonded to the heat sink 11, and the upper end face of the support block 15 abuts against the welding part 131. The support block 15 supports the welding part 131 on the pin 13, preventing the welding part 131 from being suspended. During bonding, it can prevent the welding part 131 from sinking and deforming, ensuring good welding.

[0045] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model. Therefore, any modifications, equivalent substitutions, improvements, etc., made to the above embodiments based on the actual technical aspects of the present utility model shall still fall within the scope of the technical solution of the present utility model.

Claims

1. A packaging structure to prevent pin bonding deformation, characterized in that, It includes a frame, a heat sink, and at least one chip, wherein the heat sink is mounted on the frame and the chip is attached to the upper surface of the heat sink; The frame has several pins, one end of each pin has a solder joint, the solder joint is located above the heat sink, the plane of the solder joint is parallel to the plane of the heat sink, and a gap is formed between the solder joint and the heat sink. At least one insulating support block is provided in the gap, the lower end face of the support block is bonded to the heat sink, the upper end face of the support block abuts against the solder joint, and the solder joint is soldered to the chip via a lead wire.

2. The packaging structure for preventing pin bonding deformation according to claim 1, characterized in that, The support block is a silicon block or a ceramic block.

3. The packaging structure for preventing pin bonding deformation according to claim 2, characterized in that, The silicon block is a bare silicon block, which is formed by cutting a raw wafer.

4. The packaging structure for preventing pin bonding deformation according to claim 1, characterized in that, The support block has a cuboid structure.

5. The packaging structure for preventing pin bonding deformation according to claim 4, characterized in that, The length L1 of the support block is 0.75mm to 0.85mm, and the width b of the support block is 0.55mm to 0.65mm.

6. The packaging structure for preventing pin bonding deformation according to claim 1, characterized in that, The height h of the support block is 0.3mm to 0.4mm.

7. The packaging structure for preventing pin bonding deformation according to claim 1, characterized in that, The gap is provided with multiple support blocks, which are distributed at intervals along the extension direction of the gap, and an injection flow channel is formed between two adjacent support blocks.

8. The packaging structure for preventing pin bonding deformation according to claim 7, characterized in that, The length L2 of the injection runner is not less than the length L1 of the support block.

9. The packaging structure for preventing pin bonding deformation according to claim 1, characterized in that, The heat sink is riveted, welded, glued, or screwed to the frame.

10. The packaging structure for preventing pin bonding deformation according to any one of claims 1-9, characterized in that, Several pins are distributed on the front and rear sides of the frame, and the chip is located between two opposite pins.

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