CN-116130430-B - Packaging structure of large hollow frame and preparation method thereof

Abstract

The invention discloses a packaging structure of a large hollowed-out frame, which comprises a frame body, a base island, radiating fins, pins and a plastic sealing layer, wherein the base island is arranged on the front surface of the frame body, the top of the base island is connected with a chip, the radiating fins are arranged at the bottom of the base island, the chip is connected with the pins through bonding wires, supporting connecting ribs are arranged on the hollowed-out part of the frame body, the supporting connecting ribs are distributed in a net shape, and the plastic sealing layer is arranged on the top of the frame body and coats the base island, the chip, the bonding wires and the supporting connecting ribs.

Inventors

• Qian Danyan
• WANG QIANG

Assignees

• 江苏芯德半导体科技有限公司

Dates

Publication Date

20260508

Application Date

20230130

Claims (6)

1. 1. The packaging structure of the large hollowed-out frame is characterized by comprising a frame body, a base island, radiating fins, pins and a plastic sealing layer, wherein the base island is arranged on the front surface of the frame body, the top of the base island is connected with a chip, the radiating fins are arranged at the bottom of the base island, the chip is connected with the pins through bonding wires, supporting connecting ribs are arranged on hollowed-out parts of the frame body and distributed in a net shape, the plastic sealing layer is arranged on the top of the frame body and wraps the base island, the chip, the bonding wires and the supporting connecting ribs, the supporting connecting ribs are connected with the edges of the frame body and are connected with other adjacent frame bodies, the tops of the supporting connecting ribs are level with the surface of the base island, the thickness of the supporting connecting ribs is half that of the frame body, the width of the supporting connecting ribs is more than or equal to 0.15mm, and the gap between the supporting connecting ribs is more than or equal to 0.15mm.
2. 2. The method for manufacturing the packaging structure of the large hollow frame according to claim 1, comprising the steps of: S1, etching a base island, pins, supporting connecting ribs and cooling fins on a frame body; The thickness of the support connecting ribs is half of the thickness of the frame body; the radiating fin is etched and formed at the bottom of the base island; s2, mounting a chip, wherein the chip is arranged at the top of the base island; s3, welding wires are used for connecting the chip and the pins; s4, sticking a film, namely sticking the film on the back surface of the frame body, wherein film paper is exposed at the hollowed-out part of the frame body; s5, plasma cleaning, namely performing plasma cleaning on the product with the film adhered; S6, plastic packaging, wherein the base island, the chip, the bonding wires and the support connecting ribs are coated by using plastic packaging materials; And S7, tearing the film, and removing the film paper stuck in the step S4.
3. 3. The method for manufacturing the packaging structure of the large hollow frame according to claim 2, wherein the chips and the bonding wires in the step S6 are completely covered by the plastic packaging material.
4. 4. The method for manufacturing the packaging structure of the large hollow frame according to claim 3, wherein the step S5 of plasma cleaning is to apply radio frequency voltage by using a group of electrodes, a high-frequency alternating electric field is formed between the electrodes, regional gas forms active plasma under the agitation of the alternating electric field, the active plasma performs physical impact and chemical reaction on the frame body, so that the surface substances of the product after the bonding wires are subjected to chip bonding become particles and gaseous substances, and the particles and the gaseous substances are vacuumized and discharged.
5. 5. The method for manufacturing a packaging structure of a large hollow frame according to claim 3, wherein in the step S5, argon gas impinges on the surface of the film paper exposed at the hollow portion of the frame from above the surface of the frame body in the plastic packaging process, a physical reaction is generated to roughen the surface of the film paper, a gap is formed between the film paper and the frame body, and the plastic packaging material flows into the gap.
6. 6. The method for manufacturing the packaging structure of the large hollow frame according to claim 5, wherein the plastic layer wraps the frame body, and the back surface of the frame body is not exposed with the reticular support connecting ribs.

Description

Packaging structure of large hollow frame and preparation method thereof Technical Field The invention relates to the field of semiconductor packaging, in particular to a packaging structure of a large hollow frame and a preparation method thereof. Background Along with the continuous development of integration of packaging technology, in order to adapt to the development requirements of multiple functions of products, the specificity of packaging products and frame designs is increased, and the products with special frame designs in the packaging technology field are also increased. At present, large packaged products are a long-term trend, but lead frame designs have large-area hollowed-out designs due to matching of large packaged designs and small radiating fins, namely, hollowed-out parts on the frames are large, when the whole product is actually produced, arc-striking arcs of cutting channels caused by die flow stamping exceed set values, full-automatic cutting cannot be realized, and the risk of cutting and striking arcs exists when the product is cut. Disclosure of Invention In order to solve the problems, the invention aims to provide a packaging structure of a large hollowed-out frame and a preparation method thereof, wherein the packaging structure is used for increasing the strength of the frame, reducing the impact force generated by die flow stamping in the injection molding process, improving the radian of a cutting path, reducing the arc bending risk of the cutting path, improving the toughness of the frame after plastic packaging and reducing the deformation risk of the frame. According to one aspect of the invention, the packaging structure of the large hollowed-out frame comprises a frame body, base islands, radiating fins, pins and a plastic sealing layer, wherein the base islands are arranged on the front face of the frame body, the tops of the base islands are connected with chips, the radiating fins are arranged at the bottoms of the base islands, the chips are connected with the pins through bonding wires, supporting connecting ribs are arranged on hollowed-out parts of the frame body, the supporting connecting ribs are distributed in a net shape, and the plastic sealing layer is arranged on the top of the frame body and covers the base islands, the chips, the bonding wires and the supporting connecting ribs. Through the fretwork part at the frame body, increase latticed support and link the muscle, reduce the deformation risk of frame, improve the cutting way radian. In some embodiments, the support tie bars connect the islands to the edges of the frame body and to adjacent other frame bodies. The edge connected to the frame body is connected with other adjacent frame units, and the effect is used for stabilizing the connection of unit and unit, increases whole frame intensity, reduces the frame radian. In some embodiments, the tops of the support bars are flush with the surface of the base island, and the thickness of the support bars is half of the thickness of the frame body. The back of the support rib is etched to prevent marks from being generated after plastic packaging. In some embodiments, the width of the support bars is greater than or equal to 0.15mm, and the gaps between the support bars are greater than or equal to 0.15mm. On the other hand, the invention also discloses a preparation method of the packaging structure of the large hollow frame, which comprises the following steps: S1, etching a base island, pins, supporting connecting ribs and cooling fins on a frame body; The thickness of the support connecting ribs is half of the thickness of the frame body; the radiating fin is etched and formed at the bottom of the base island; s2, mounting a chip, wherein the chip is arranged at the top of the base island; s3, welding wires are used for connecting the chip and the pins; s4, sticking a film, namely sticking the film on the back surface of the frame body, wherein film paper is exposed at the hollowed-out part of the frame body; s5, plasma cleaning, namely performing plasma cleaning on the product with the film adhered; S6, plastic packaging, wherein the base island, the chip, the bonding wires and the support connecting ribs are coated by using plastic packaging materials; And S7, tearing the film, and removing the film paper stuck in the step S4. In some embodiments, in S6, both the chip and the bonding wires are completely covered by the molding compound. In some embodiments, the S5 plasma cleaning is to apply radio frequency voltage to a group of electrodes, a high-frequency alternating electric field is formed between the electrodes, the regional gas is subjected to physical impact and chemical reaction by the frame body under the oscillation of the alternating electric field, so that the product surface substances after bonding wires are arranged into chips are changed into particles and gaseous substances, and the particles and the gaseous substances are disch