Non-pin high-voltage high-heat-dissipation product frame design structure

Abstract

The utility model relates to the technical field of semiconductor high-heat-dissipation chip packaging, in particular to a no-pin high-voltage high-heat-dissipation product frame design structure, which structurally comprises a frame body, a frame base island and a chip, a plurality of product pins are arranged at the edge of the frame body, the frame base island is connected with the frame body through a base island connecting rib, and the chip is connected with the frame body. A plurality of through holes are formed in the edge of the frame base island, the chip is arranged on a chip area of the frame base island, the cooling fins are arranged on the bottom face of the chip through chip bonding glue, the product pins are connected with the plastic package body in a reflow soldering paste mode, solder paste forms solder balls on the surface of the plastic package body, and the solder balls are used for outputting product signals. The surface exposing the solder balls is the bottom surface of the product, and the cooling fin is located on the top surface of the product. According to the utility model, the radiating fins are arranged on the front surface of the product, so that the heat of the chip is output from the front surface of the product, the product can quickly transfer the heat at the application end, the product performance is stabilized, and the use standard of customers is met.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor high heat dissipation chip packaging, in particular to a pinless high-voltage high heat dissipation product frame design structure. Background Art

[0002] In the semiconductor field, power semiconductor devices are crucial in the distribution and management of power and energy. The improvement of the performance of power semiconductor devices themselves is the driving force for improving the performance of power systems in terms of power density, power efficiency, operating frequency, reliability, etc. The Quad Flat No-leads Package (QFN) product does not have any epitaxial pins. Since the QFN package has no pins and its size is smaller than that of traditional packages, it is very suitable for use in electronic devices that have strict requirements on size and weight, such as mobile phones, digital cameras, PDAs and other portable small electronic devices.

[0003] The structure of conventional QFN products includes a package substrate, chip, conductive pad, exposed pad, packaging material, and other structures, such as a heat sink, thermal pad, etc. The heat sink is set on the bottom of the conventional QFN product through a high-heat dissipation adhesive material. However, due to the continuous improvement of product performance requirements, the conventional product QFN heat dissipation structure can no longer meet the requirements of the application end. For example, the heat generated under high power may still not be effectively dissipated, resulting in an increase in chip temperature. Utility Model Content

[0004] Aiming at the problem that the heat dissipation structure of QFN products in the prior art cannot meet the application requirements, the utility model provides a pinless high-voltage and high-heat dissipation product frame design structure.

[0005] The utility model is realized by the following technical solutions:

[0006] A pinless high-voltage and high-heat dissipation product frame design structure comprises a frame body, a frame base island, a chip and a heat sink, a plurality of product pins are arranged at the edge of the frame body, the frame base island is connected to the frame body through base island connecting ribs, a plurality of through holes are arranged at the edge of the frame base island, the chip is arranged on the chip area of ​​the frame base island, the heat sink is arranged on the bottom surface of the chip through adhesive, the chip is respectively connected to the edge of the frame base island and the product pins through bonding wires; an anti-overflow step is arranged at the edge of the base island, and an anti-overflow glue groove is opened at the edge of the chip; the product pins are connected to the plastic package body by means of reflow solder paste, and the solder paste forms solder balls on the surface of the plastic package body, the solder balls are used to output product signals, the side where the solder balls are exposed is the bottom surface of the product, and the heat sink is located on the top surface of the product.

[0007] Preferably, the product pins and the frame base island are located in different planes.

[0008] Preferably, the product pins are connected to the frame base island via bent base island connecting ribs.

[0009] Preferably, each base island connecting reinforcement is bent twice.

[0010] Preferably, the base island connecting reinforcement is bent twice to form a first step, a second step and a third step arranged up and down, the first step is in the same plane with the product pin, and the third step is in the same plane with the frame base island.

[0011] Preferably, the bending angle of the base island connecting reinforcement is 120° to 155°.

[0012] Preferably, the length of the base island connecting rib is determined according to the overall thickness and bending depth of the product.

[0013] Preferably, the length of the base island connecting rib is 3.0 mm.

[0014] Preferably, the cross section of the through hole is rectangular.

[0015] Preferably, the through holes located at the four corners of the frame base island are "L" shaped.

[0016] Compared with the prior art, the utility model has the following beneficial effects:

[0017] The utility model discloses a pinless high-voltage and high-heat dissipation product frame design structure. Through the design of the frame structure, a heat sink is arranged on the front of the product, so that the heat of the chip will be output from the front of the product, so that the product can quickly transfer heat at the application end, stabilize the product performance, and meet the customer's usage standards; at the same time, the characteristics of the heat sink itself determine that the power device has the advantages of large on-current density, high output power density, good switching recovery characteristics, high heat dissipation power efficiency and excellent high-temperature working characteristics, so that the modified package product has excellent physical properties such as high temperature resistance, high voltage resistance, high frequency and high power, which brings huge system advantages to industrial applications in terms of improving energy efficiency, system miniaturization, and improving voltage resistance, and can be applied to consumer electronics, data centers, 5G base stations, new energy vehicles and other fields.

[0018] Furthermore, two bending processes are adopted to facilitate processing. If the number of bending processes is less, such as one time, it cannot be achieved in the production process because the bending depth is too large; the more bending times, the greater the processing difficulty, the higher the cost, and the worse the operability. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of a pinless high-voltage and high-heat dissipation product frame design structure of the utility model;

[0020] Figure 2 yes Figure 1 Sectional view at AA in the middle;

[0021] Figure 3 It is a front view schematic diagram of a pinless high-voltage and high-heat dissipation product frame design structure before plastic sealing of the utility model;

[0022] Figure 4 yes Figure 2 Cross-sectional view at the middle BB.

[0023] In the figure, 1. Product pins; 2. Ground ring line; 3. Anti-overflow glue groove; 4. Chip area; 5. Base island connecting ribs; 6. First bending position; 7. Second bending position; 8. Exposed heat sink; 9. Adhesive glue; 10. Chip; 11. Plastic encapsulation material; 12. Bonding wire; 13. Solder ball. DETAILED DESCRIPTION

[0024] The present invention will be further described in detail below in conjunction with specific embodiments, which are intended to explain the present invention rather than to limit it.

[0025] The utility model discloses a pinless high-voltage high-heat dissipation product frame design structure, referring to Figure 1 , including a frame body, a frame base island and a chip 10. A plurality of product pins 1 are arranged on the edge of the frame body. A ground ring line 2 is arranged on the frame base island. The frame base island is connected to the frame body through a base island connecting rib 5. In this embodiment, the length of the frame pin is designed according to the size of the packaged chip 10 and the manufacturability. The lengthened pin can reduce the length of the welding wire and improve the product signal transmission. The product pin 1 is connected to the frame base island through the base island connecting rib 5 that has been bent by mechanical equipment, so that the product pin 1 and the frame base island are located in different planes. In this embodiment, each base island connecting rib 5 is bent twice, refer to Figure 2 The base island connecting rib 5 is bent twice to form a first step, a second step and a third step arranged up and down. The first step is in the same plane with the product pin 1, and the third step is in the same plane with the frame base island. The bending angle of the base island connecting rib 5 is evaluated according to the product thickness, the frame thickness, and the material hardness. In this embodiment, the bending angle is 120°~155°.

[0026] The length of the base island connecting rib 5 is determined according to the overall thickness of the product and the bending depth. In this embodiment, the length of the base island connecting rib 5 is 3.0 mm, the first bending position 6 is 0.83 mm, and the second bending position 7 is 2.530 mm.

[0027] A plurality of through holes are provided at the edge of the frame base island to improve the wrapping strength between the plastic packaging material 11 and the frame, and to improve product reliability and quality. In this embodiment, the through holes are 1.0 mm*0.15 mm rectangular and are "L" shaped at the corners.

[0028] Reference Figure 3 , 4 The chip 10 is arranged on the chip area 4 of the frame base island, and the heat sink 8 is arranged on the bottom surface of the chip 10 through the adhesive 9, so that the heat can be dissipated from the top of the product, so that the product can quickly transfer heat at the application end, stabilize product performance, and meet customer usage standards.

[0029] The chip 10 is connected to the edge of the frame base island and the product pin 1 respectively through bonding wires 12; an anti-overflow step is provided on the edge of the base island, and an anti-overflow glue groove 3 is opened on the edge of the chip 10; the product pin 1 is connected to the plastic sealing body formed by the plastic sealing material 11 by means of reflow solder paste, and the solder paste forms a solder ball 13 on the surface of the plastic sealing body, and the solder ball 13 is used to output the product signal, and the side where the solder ball 13 is exposed is the bottom surface of the product, and the heat sink 8 is located on the top surface of the product.

[0030] The utility model also discloses a packaging method of a pinless high-voltage high-heat dissipation product frame design structure, comprising the following steps:

[0031] Step 1: Design the front through hole and heat sink on the front of the frame, and design the dimple hole at the root of the pin, refer to Figure 1 ;

[0032] Step 2: Make an anti-overflow step on the edge of the base island and an anti-overflow glue groove 3 on the edge of the chip 10, refer to Figure 2 ;

[0033] Step 3, making a frame by etching method, and electroplating silver on the frame;

[0034] Step 4: bend the base island connecting rib 5 of the silver-plated frame twice, refer to Figure 2 ;

[0035] Step 5: On the frame base island, core mounting, pressure welding, film lamination, plastic sealing, printing, laser drilling, solder paste application, reflow soldering and cutting are performed in sequence to complete the packaging and obtain the packaged product (such as Figure 3 , 4 In this embodiment, after plastic encapsulation, a hole is drilled on the plastic encapsulation body corresponding to each pin by laser drilling, so that each pin is provided with a tin hole, and tin paste is injected through the tin hole, so that the tin paste is connected to the pin and is conductive, and then a tin ball 13 is formed on the surface of the plastic encapsulation body by reflow soldering, and the signal of the product is output through the tin ball 13.

[0036] The above description is only a preferred embodiment of the present invention and is not intended to impose any limitation on the technical solution of the present invention. Those skilled in the art should understand that, without departing from the spirit and principles of the present invention, the technical solution can also be subjected to several simple modifications and replacements, and these modifications and replacements are also within the scope of protection covered by the claims.

Claims

1. A pinless high-voltage and high-heat dissipation product frame design structure, characterized in that: The invention comprises a frame body, a frame base island and a chip (10); a plurality of product pins (1) are arranged on the edge of the frame body; the frame base island is connected to the frame body via a base island connecting rib (5); a plurality of through holes are arranged on the edge of the frame base island; the chip (10) is arranged on a chip area (4) of the frame base island; a heat sink (8) is arranged on the bottom surface of the chip (10) via a chip adhesive (9); the front surface of the chip (10) is respectively connected to the edge of the frame base island and the product pins (1) via a bonding wire (12); an anti-overflow step is arranged on the edge of the base island; an anti-overflow glue groove (3) is opened on the edge of the chip (10); the product pins (1) are connected to the plastic package body by means of reflow solder paste, and the solder paste forms a solder ball (13) on the surface of the plastic package body; the solder ball (13) is used to output a product signal; the side where the solder ball (13) is exposed is the bottom surface of the product; and the heat sink (8) is located on the top surface of the product.

2. The pinless high-voltage and high-heat dissipation product frame design structure according to claim 1 is characterized in that: The product pins (1) are located in different planes from the frame base island.

3. The pinless high-voltage and high-heat dissipation product frame design structure according to claim 2 is characterized in that: The product pin (1) is connected to the frame base island via a base island connecting rib (5) that has been bent.

4. The pinless high-voltage and high-heat dissipation product frame design structure according to claim 3 is characterized in that: Each base island connecting reinforcement (5) is subjected to two bending processes.

5. The pinless high-voltage and high-heat dissipation product frame design structure according to claim 4 is characterized in that: The base island connecting rib (5) is bent twice to form a first step, a second step and a third step arranged up and down, the first step and the product pin (1) are in the same plane, and the third step and the frame base island are in the same plane.

6. The pinless high-voltage and high-heat dissipation product frame design structure according to claim 4 is characterized in that: The bending angle of the base island connecting reinforcement (5) is 120° to 155°.

7. The pinless high-voltage and high-heat dissipation product frame design structure according to claim 3 is characterized in that: The length of the base island connecting rib (5) is determined according to the overall thickness of the product and the bending depth.

8. The pinless high-voltage and high-heat dissipation product frame design structure according to claim 3 is characterized in that: The length of the base island connecting rib (5) is 3.0 mm.

9. The pinless high-voltage and high-heat dissipation product frame design structure according to claim 1 is characterized in that: The cross section of the through hole is rectangular.

10. The pinless high-voltage and high-heat dissipation product frame design structure according to claim 1, characterized in that: The through holes located at the four corners of the frame base island are "L" shaped.

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