CN117476590A - Double-sided heat dissipation packaging structure and preparation method thereof - Google Patents

Abstract

The invention discloses a double-sided radiating packaging structure and a preparation method thereof, wherein the packaging structure is formed by bonding an S pole and a G pole of a chip through a specific carrier, and the size of the carrier can be adjusted according to the windowing sizes of the S pole and the G pole of the chip so as to adapt to different MOS chip sizes; the D pole of the chip is arranged on the upper surface of the product, and the copper sheet adhesive structure is matched, so that the product realizes double-sided heat dissipation, and meanwhile, the heat dissipation area with the same size as the upper surface of the product is obtained, the heat dissipation is greatly improved, and the product reliability of the power device is improved; meanwhile, the D pole of the chip is arranged on the upper surface of the power device, and the copper sheet bonding structure is matched, so that the power device product has smaller packaging volume and higher product voltage and power. The preparation method of the packaging structure provided by the invention improves the performance and the production yield of the product.

Description

A double-sided heat dissipation packaging structure and its preparation method

Technical field

The invention relates to the technical field of semiconductor power device packaging, and in particular to a double-sided heat dissipation packaging structure and a preparation method thereof.

Background technique

In the field of existing semiconductor power device packaging and manufacturing, taking surface mount device DFN packaging as an example, a carrier (PAD) is generally set up in the lead frame, and leads are set around the carrier. The D pole of the MOS tube is connected to the carrier through adhesive glue. The MOS The S and G poles of the tube are bonded to the frame through bonding wires such as gold wires, copper wires, and aluminum wires, and the chip is electrically connected to the external circuit through the carrier and external lead terminals.

Currently, the traditional packaging structure used requires the size of the chip to be smaller than the size of the carrier. With the development of power device packaging technology, higher requirements have been put forward for products. It is necessary to package larger chips in smaller products as much as possible in order to reduce the product outline volume, provide higher power and better heat dissipation. effect, as well as smaller interference and better product electrical performance. The traditional packaging method cannot meet the needs of packaging larger chips, so a packaging structure that can package larger chips in the same package shape is needed.

Contents of the invention

The first aspect of the present invention provides a double-sided heat dissipation packaging structure. This structure uses a specific carrier to bond the S pole and G pole of the chip. The size of the carrier can be adjusted according to the window size of the S pole and G pole of the chip, thereby Adapt to different MOS tube chip sizes; by placing the D pole of the chip on top and using the copper sheet bonding structure, the product achieves double-sided heat dissipation, and at the same time obtains a heat dissipation area of the same size as the upper surface of the product, greatly improving heat dissipation. , improve the reliability of power device products; at the same time, by placing the D pole of the chip on top and combining with the copper chip bonding structure, the power device products have a smaller packaging volume and higher product voltage and power.

A second aspect of the present invention provides a method for preparing the above-mentioned packaging structure. This method greatly improves abnormal conditions such as voids, dirt, and delamination of the product through vacuum reflow + solder paste cleaning. Through the FC core + solder paste process combined with product structure design, the reliability and electrical performance of the product are greatly improved. Through the grinding and cutting process, the upper surface of the product can be the entire heat dissipation surface, which greatly reduces the Rth of the product and provides better heat dissipation effect.

The technical solutions provided by the invention are as follows:

A double-sided heat dissipation packaging structure, including:

Lead frame, chip, Clip heat dissipation copper sheet and plastic package;

The lead frame includes the back of the frame carrier, the D pole lead of the frame and the G pole lead of the frame. There are frame connecting ribs on both sides of the back of the frame carrier. One end of the back of the frame carrier is connected to one or more frame S pole leads. The back side of the frame carrier, the frame connecting ribs and the frame S-pole lead are arranged coplanarly and leak out of the plastic package after packaging. The frame S-pole lead is formed into an S-pole electrode after plastic packaging. A carrier is provided on the back side of the frame carrier. S pole connection surface;

The frame D-pole lead is arranged on the back side of the frame carrier away from the frame S-pole lead. The number of the frame D-pole leads is one or more, and all the frame D-pole leads are arranged on the same lead. On the foot connection part, the D pole lead of the frame, the pin connection part and the back side of the frame carrier are arranged in the same plane, and the D pole lead of the frame and the pin connection part are plastic-sealed and leak out of the plastic package. A D-pole electrode is formed, and a carrier D-pole connection surface is provided on the back of the D-pole lead of the frame and the pin connection part;

The G-pole lead of the frame is arranged on the same side as the S-pole lead of the frame on the back of the frame carrier. The G-pole lead of the frame is coplanar with the back of the frame carrier. The G-pole lead of the frame leaks out of the plastic package after being plastic-sealed. An S pole electrode is formed, and a carrier G pole connection surface is provided on the back of the G pole lead of the frame;

One side of the chip is connected to the S-pole connection surface and the G-pole connection surface of the carrier respectively, and the other side is connected to the Clip chip connection part, and the Clip chip connection part is connected to the D-pole connection surface of the carrier; The size of the chip is larger than the size of the back side of the frame carrier;

A Clip heat dissipation copper sheet is provided on the Clip chip connection part, and the upper surface and side surfaces of the Clip heat dissipation copper sheet leak out of the plastic package to form a Clip heat dissipation surface;

The Clip chip connection part and the chip are both plastic-sealed in the plastic package body.

Further, it also includes solder paste, which includes chip S-pole solder paste, lead D-pole solder paste, chip D-pole solder paste and G-pole solder paste;

The S-pole solder paste of the chip connects the S-electrode of the chip and the S-pole connection surface of the carrier to provide an S-pole electrical path;

The D-pole solder paste of the lead connects the chip and the D-pole connection surface of the carrier;

The D-pole solder paste of the chip connects the D-electrode of the chip and the Clip chip connection part, electrically transmits the D-electrode to the Clip copper sheet, and provides an electrical path for the D-electrode;

The G-electrode solder paste connects the G-electrode of the chip and the G-electrode connection surface of the carrier to provide a G-electrode electrical path.

Further, the Clip chip connection part and the Clip heat dissipation copper sheet are connected through transition fillets. Clip slots are provided on both sides of the Clip heat dissipation copper sheet. During the packaging process, the Clip heat dissipation copper sheet is packaged in a plastic package. In the body, the upper surface of the Clip heat dissipation copper sheet is exposed through grinding to form a Clip heat dissipation surface, and the side surface of the Clip heat dissipation copper sheet is exposed out of the plastic package through cutting.

Further, a downward frame carrier step is provided on the peripheral side of the back of the frame carrier, and the back of the frame carrier step forms the S-pole connection surface of the carrier;

A downward pin connection step is provided on the peripheral side of the pin connection part, and the back side of the pin connection part step forms the D-pole connection surface of the carrier;

A downward G-pole lead step is provided on the peripheral side of the G-pole lead of the frame, and the back surface of the G-pole lead step forms the G-pole connection surface of the carrier.

Further, a Clip chip connection surface is provided on the Clip chip connection part, and a Clip chip connection surface fillet is provided on the Clip chip connection surface.

Further, a Clip lead connection part is provided at one end of the Clip chip connection part, and a Clip chip connection surface fillet is provided on the Clip lead connection part.

Further, a Clip step is provided between the Clip chip connection part and the Clip lead connection part, and a groove is formed at the position of the Clip step.

Further, the number of S-pole leads of the frame is 3, and the three S-pole leads of the frame are equally spaced;

The number of D-pole leads of the frame is 4, and the four D-pole leads of the frame are equally spaced.

Further, the distance between the Clip heat dissipation surface and the product outline is 0.1 mm.

At the same time, the present invention also provides a method for preparing a double-sided heat dissipation packaging structure, which is used to prepare the above-mentioned double-sided heat dissipation packaging structure, including the following steps:

The lead frame is obtained through etching process;

The wafer is thinned and diced, and the MOS tube is flip-chip-mounted on the diced wafer. The D-pole area of the chip is copper-plated. After the die is mounted, Clip heat-dissipation copper sheets are mounted;

The Clip heat dissipation copper sheet is vacuum reflowed after being patched, and then the residue of solder paste volatiles is cleaned;

Apply film to the back of the frame carrier, clean it before plastic sealing, plastic seal the product, and post-cure after plastic sealing;

After post-curing, boil and soften, remove overflow, electroplating after softening, bake after electroplating, grind the product after baking to remove Clip heat dissipation copper sheets;

After the Clip heat dissipation copper sheet is leaked, it is printed, then cut and separated. After cutting into individual products, the product is tested. After passing the test, it is packaged and stored in the warehouse.

Compared with the prior art, the beneficial effects of the present invention are:

1. The present invention uses the lead frame carrier as the S pole and the G pole to be directly led out, and the D pole is led out through the Clip heat dissipation copper sheet. This structure greatly reduces the length of the electrical transmission path, increases the conductive cross-sectional area, and greatly reduces the The internal resistance of the product improves the electrical performance of the power device product; this structure uses a specific carrier to bond the S pole and G pole of the chip, and the size of the carrier can be adjusted according to the window size of the S pole and G pole of the chip, thereby adapting to Equipped with different MOS tube chip sizes;

2. In the present invention, a frame carrier step is set downward around the outer contour of the back of the frame carrier. The back of this step is the S-pole connection surface of the carrier. It can be adjusted according to the size of the S-pole window of the chip. The frame carrier step can increase the number of connections between the carrier and the carrier. The bonding force of plastic sealing materials improves packaging strength;

3. The present invention optimizes the electrical propagation path distance and propagation cross-sectional area through the structure of the solder paste sheet + copper sheet through three electrodes, and reduces the internal resistance of the power device product;

4. This invention enables the product to achieve double-sided heat dissipation by placing the D-pole of the chip on the top and using the copper sheet bonding structure. At the same time, the heat dissipation area is the same size as the upper surface of the product, which greatly improves heat dissipation and improves power. Device product reliability.

5. In this invention, by placing the D pole of the chip on top and cooperating with the copper sheet bonding structure, the power device product obtains a smaller packaging volume and higher product voltage and power;

6. The present invention improves product performance and production yield through the preparation method of a double-sided heat dissipation packaging structure;

7. The method for preparing a double-sided heat-dissipating packaging structure provided by the present invention greatly improves product abnormalities such as voids, dirt, and delamination through vacuum reflow + solder paste cleaning. Through the FC core + solder paste process combined with product structure design, the reliability and electrical performance of the product are greatly improved. Through the grinding and cutting process, the upper surface of the product can be the entire heat dissipation surface, which greatly reduces the Rth of the product and provides better heat dissipation effect.

Description of the drawings

Figure 1 is a schematic diagram of the internal structure of a double-sided heat dissipation package structure in an embodiment of the present invention;

Figure 2 is a schematic diagram of the lead frame structure of a double-sided heat dissipation package structure in an embodiment of the present invention;

Figure 3 is a side view of the internal structure of the double-sided heat dissipation packaging structure in the embodiment of the present invention;

Figure 4 is a schematic structural diagram of the Clip heat dissipation copper sheet in the embodiment of the present invention;

Figure 5 is a backside outline view of a double-sided heat dissipation packaging structure in an embodiment of the present invention;

FIG. 6 is a front appearance view of a double-sided heat dissipation packaging structure in an embodiment of the present invention.

The reference numbers are as follows:

1-Back side of the frame carrier; 2-Frame reinforcement; 3-Frame D pole lead; 4-Pin connection part; 5-Pin connection part step; 6-Frame S pole lead; 7-Frame carrier step; 8-Chip S pole solder paste; 9 - frame G pole lead; 10 - G pole lead step; 11 - G pole solder paste; 12 - chip; 13 - chip D pole solder paste; 14 - lead D pole solder paste; 15 - Clip chip Connection surface; 16-Clip lead connection surface; 17-Clip step; 18-Clip lead connection part; 19-Clip chip connection part; 20-Clip heat dissipation copper sheet; 21-Clip chip connection surface fillet; 22-Transition fillet ; 23-Clip heat dissipation surface; 24-plastic package; 25-carrier S-pole connection surface; 26-carrier D-pole connection surface; 27-carrier G-pole connection surface; 28-Clip slotting.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions 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 embodiments described below are some of the embodiments of the present application, but not all of the embodiments. The components of the embodiments of the present application generally described and illustrated in the figures herein may be arranged and designed in a variety of different configurations.

Accordingly, the detailed description of the embodiments of the present application provided below in connection with the appended drawings is intended to represent only selected embodiments of the present application and is not intended to limit the scope of the present application. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without any creative work shall fall within the scope of protection of this application.

In the description of the embodiments of the present invention, it should be noted that, unless otherwise expressly specified and limited, the terms "setting", "installation", "connecting" and "connecting" should be understood in a broad sense. For example, they can be fixed The connection can also be a detachable connection or an integral connection; it can be a mechanical connection, an electrical connection or mutual communication; it can be a direct connection or an indirect connection through an intermediary, or it can be an internal connection between two components. or the interaction between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

Referring to FIGS. 1 to 6 , the present invention provides a double-sided heat dissipation packaging structure, including a lead frame, a chip 12 , a Clip heat dissipation copper sheet 20 and a plastic package 24 .

The lead frame includes the back side of the frame carrier 1, the D pole lead 3 of the frame, and the G pole lead 9 of the frame. There are frame connecting ribs 2 on both sides of the back side 1 of the frame carrier. One end of the back side 1 of the frame carrier is connected to one or more frame S pole leads 6. , the back side of the frame carrier 1, the frame connecting ribs 2 and the frame S-pole lead 6 are coplanarly arranged and leak out of the plastic package 24 after packaging. The frame S-pole lead 6 forms the S-pole electrode of the package structure after plastic packaging. The back side of the frame carrier 1 is provided with Carrier S pole connection surface 25.

In this embodiment, the back side 1 of the lead frame carrier is used as the back side of the product. The back side of the product is welded to the PCB circuit board through solder. The three electrodes of the MOS tube are connected through the back side 1 of the frame carrier, the D electrode lead 3 of the frame, and the G electrode lead 9 of the frame. lead out.

The D pole lead 3 of the frame is arranged on the back side of the frame carrier 1 away from the S pole lead 6 of the frame. The number of the D pole leads 3 of the frame is one or more. All the D pole leads 3 of the frame are arranged on the same pin connection part 4 , the D-pole lead 3 of the frame, the pin connection part 4 and the back side 1 of the frame carrier are arranged in the same plane, and the D-pole lead 3 and the pin connection part 4 of the frame are plastic-sealed and leak out of the plastic package 24 to form the D-pole electrode of the package structure. , a carrier D-pole connection surface 26 is provided on the back of the frame D-pole lead 3 and the pin connection part 4 .

The frame G pole lead 9 is arranged on the same side of the frame carrier back 1 and the frame S pole lead 6. The frame G pole lead 9 is coplanar with the frame carrier back 1. After the frame G pole lead 9 is plastic-sealed, it leaks out of the plastic package 24 to form the S pole electrode. , the back side of the frame G pole lead 9 is provided with a carrier G pole connection surface 27.

One side of the chip 12 is connected to the carrier S-pole connection surface 25 and the carrier G-pole connection surface 27 respectively, and the other side is connected to the Clip chip connection part 19, and the Clip chip connection part 19 is connected to the carrier D-pole connection surface 26; the size of the chip 12 Larger than the dimensions of the back side 1 of the frame carrier.

A Clip heat dissipation copper sheet 20 is provided on the Clip chip connection part 19. The upper surface and side surfaces of the Clip heat dissipation copper sheet 20 leak out of the plastic package 24 to form a Clip heat dissipation surface 23, as shown in FIG. 6 .

The Clip chip connection part 19 and the chip 12 are both plastic-sealed in the plastic package 24 . After the package structure is encapsulated, the side of the frame carrier back 1 that leaks from the plastic package 24 is defined as the back of the product. The specific appearance structure is shown in Figure 5; the side of the Clip heat dissipation copper sheet 20 that leaks from the plastic package 24 is defined as the product. On the front side of the product, in addition to the back side of the frame carrier 1, the frame connecting ribs 2, the frame D pole lead 3, the pin connection part 4, the frame S pole lead 6 and the frame G pole lead 9 leak out from the back, the Clip heat dissipation copper sheet 20 leaks out from the front Except for the leakage, the rest of the structure is encapsulated in the plastic package 24 .

Optionally, solder paste is also included, which includes chip S-pole solder paste 8, lead D-pole solder paste 14, chip D-pole solder paste 13 and G-pole solder paste 11. The chip S-pole solder paste 8 connects the S-electrode of the chip 12 and the carrier S-pole connection surface 25 to provide an S-pole electrical path. The lead D-pole solder paste 14 connects the chip 12 and the carrier D-pole connection surface 26 . The chip D electrode solder paste 13 connects the D electrode of the chip 12 and the Clip chip connection part 19, electrically transmits the D electrode to the Clip heat dissipation copper sheet 20, and provides an electrical path for the D electrode. The G-electrode solder paste 11 connects the G-electrode of the chip 12 and the carrier G-electrode connection surface 27 to provide a G-electrode electrical path.

Different from traditional power device packaging, the traditional package uses the lead frame carrier as the D pole lead-out terminal of the chip, and the S pole and G pole are led out through wire bonding. In the present invention, the lead frame carrier serves as the S pole and G pole through solder paste. The adhesive sheet is directly led out, and the D pole is led out through the Clip heat dissipation copper sheet 20. This structure greatly reduces the length of the electrical transmission path, increases the conductive cross-sectional area, greatly reduces the internal resistance of the product, and improves the efficiency of the power device product. electrical properties.

As shown in Figure 3 and Figure 4, the Clip chip connection part 19 and the Clip heat dissipation copper sheet 20 are connected through the transition fillet 22. Clip heat dissipation copper sheet 20 is provided with Clip slots 28 on both sides. During the packaging process, the Clip heat dissipation copper sheet 20 is encapsulated in a plastic package 24. The Clip heat dissipation copper sheet 20 is exposed from the upper surface through grinding to form a Clip heat dissipation surface 23. The side surface of the Clip heat dissipation copper sheet 20 is exposed from the plastic package 24 through cutting.

As shown in FIG. 1 , a downward frame carrier step 7 is provided on the peripheral side of the back surface 1 of the frame carrier. The back surface of the frame carrier step 7 forms a carrier S-pole connecting surface 25 .

In this embodiment, a frame carrier step 7 is set downward around the outer contour of the back side 1 of the frame carrier. The back side of this step is the carrier S-pole connection surface 25, which can be adjusted according to the size of the S-pole window of the chip 12. The frame carrier step 7 can increase the binding force between the carrier and the plastic sealing material and improve the packaging strength.

A downward pin connection step 5 is provided on the four peripheral sides of the pin connection part, and the back surface of the pin connection step 5 forms a carrier D-pole connection surface 26 .

In this embodiment, a pin connection step 5 is set downward around the outline of the pin connection part 4. The pin connection step 5 can increase the binding force between the pin connection part 4 and the plastic packaging material and improve the packaging strength.

A downward G pole lead step 10 is provided on the peripheral side of the frame G pole lead 9, and the back side of the G pole lead step 10 forms a carrier G pole connection surface 27.

In this embodiment, a downward G-pole lead step 10 is set around the outer contour of the frame G-pole lead 9. The back of this step is the carrier G-pole connection surface 27. The G-pole lead step 10 can increase the connection between the frame G-pole lead 9 and the plastic packaging material. The bonding force improves the packaging strength.

As shown in FIG. 3 , the Clip chip connection portion 19 is provided with a Clip chip connection surface 15 , and the Clip chip connection surface 15 is provided with a Clip chip connection surface fillet 21 .

In this embodiment, the Clip chip connection surface 15 is provided on the Clip chip connection part 19 and the Clip chip connection surface fillet 21 is provided on the Clip chip connection surface 15 to avoid scratching the chip 12 during the bonding process.

Optionally, one end of the Clip chip connection part 19 is provided with a Clip lead connection part 18, and the Clip lead connection part 18 is provided with a Clip chip connection surface fillet 21.

In this embodiment, a boss-shaped Clip lead connection part 18 is provided at one end of the Clip chip connection part 19. The top of the boss is the Clip lead connection surface 16, and the Clip chip connection surface fillet 21 is provided on the Clip lead connection surface 16. Avoid scratching the chip 12 during the bonding process.

Optionally, a Clip step 17 is provided between the Clip chip connection part 19 and the Clip lead connection part 18, and a groove is formed at the position of the Clip step 17.

In this embodiment, a Clip step 17 is provided between the Clip chip connection part 19 and the Clip lead connection part 18, and a groove is formed at the step position. This groove can make way for the chip 12 to ensure that the plastic packaging material is filled.

Optionally, the number of frame S pole leads 6 is three, and the three frame S pole leads 6 are equally spaced.

The number of frame D-pole leads 3 is 4, and the four frame D-pole leads 3 are equally spaced.

Optionally, the minimum distance between the Clip heat dissipation surface 23 and the product outline is 0.1mm.

In the present invention, the chip S-pole and chip G-pole window areas are bonded to the lead frame carrier through solder paste. The size of the chip 12 can be larger than the size of the carrier. It only needs to design a safe packaging size from the edge of the chip 12 to the plastic package 24. That’s it, the minimum is 0.1mm, so MOS tubes under the same package size can package larger chips, thereby obtaining greater product voltage and power, and providing a larger selection range of chip 12 sizes. Inversely speaking, it can Under the same product performance, a smaller power device product package size can be obtained.

The circuit connection relationship of the above-mentioned double-sided heat dissipation packaging structure provided by the present invention is as follows:

S pole path: chip S pole opening → chip S pole solder paste 8 → carrier S pole connection surface 25 → frame carrier backside 1, frame S pole lead 6 → soldered to the PCB circuit board.

D pole path: chip D pole opening window → chip D pole solder paste 13 → Clip chip connection surface 15 → Clip chip connection part 19 → Clip heat dissipation copper sheet 20 → Clip lead connection part 18 → Clip lead connection surface 16 → lead D pole Solder paste 14→carrier D-pole connection surface 26→pin connection part 4, frame D-pole lead 3→soldered to the PCB circuit board.

G pole path: chip G pole opening → G pole solder paste 11 → carrier G pole connection surface 27 → frame G pole lead 9 → soldered to the PCB circuit board.

The present invention provides a method for preparing a double-sided heat dissipation packaging structure, which is used to prepare the above-mentioned double-sided heat dissipation packaging structure. The packaging process of the preparation method is: wafer thinning → wafer dicing → lead frame loading → Solder paste printing → FC core mounting → Solder paste printing → Clip mounting → Vacuum reflow soldering → Solder paste cleaning → Frame film → Cleaning before plastic sealing → Plastic sealing → Post-curing → Hot boiling and softening → Overflow removal → Electroplating → Baking → Grinding → Print → Cut and separate → Test → External inspection and packaging → Warehousing, including the following steps:

The lead frame is obtained through etching process;

The wafer is thinned and diced, and the MOS tube is flip-chip mounted on the diced wafer. The D-pole area of the chip is plated with copper. After the wafer is mounted, a Clip heat dissipation copper sheet 20 is mounted;

After the Clip heat dissipation copper sheet 20 is mounted, it is vacuum reflowed, and then the residue of solder paste volatiles is cleaned;

Apply a film to the back side 1 of the frame carrier, clean it, and then plastic seal the product. After plastic sealing, perform post-curing;

After post-curing, heat boiling is performed to soften, and overflow is removed. After softening, electroplating is performed. After electroplating, baking is performed. After baking, the product is ground to remove Clip heat dissipation copper sheets 20;

After the Clip heat dissipation copper sheet 20 is leaked, it is printed, then cut and separated. After cutting into single products, the product is tested. After passing the test, it is packaged and stored in the warehouse.

The method for preparing a double-sided heat-dissipating packaging structure provided by the present invention greatly improves abnormal conditions such as voids, dirt, and delamination of the product through vacuum reflow soldering and solder paste cleaning. Through the FC core + solder paste process combined with product structure design, the reliability and electrical performance of the product are greatly improved. Through the grinding and cutting process, the upper surface of the product can be the entire heat dissipation surface, which greatly reduces the Rth of the product and provides better heat dissipation effect.

The above are only the best specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present application shall be covered by the protection scope of the present application. within. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

Claims (10)

1. A double-sided heat dissipation packaging structure, characterized by including: Lead frame, chip, Clip heat dissipation copper sheet and plastic package; The lead frame includes the back of the frame carrier, the D pole lead of the frame and the G pole lead of the frame. There are frame connecting ribs on both sides of the back of the frame carrier. One end of the back of the frame carrier is connected to one or more frame S pole leads. The back side of the frame carrier, the frame connecting ribs and the frame S-pole lead are arranged coplanarly and leak out of the plastic package after packaging. The frame S-pole lead is formed into an S-pole electrode after plastic packaging. A carrier is provided on the back side of the frame carrier. S pole connection surface; The frame D-pole lead is arranged on the back side of the frame carrier away from the frame S-pole lead. The number of the frame D-pole leads is one or more, and all the frame D-pole leads are arranged on the same lead. On the foot connection part, the D pole lead of the frame, the pin connection part and the back side of the frame carrier are arranged in the same plane, and the D pole lead of the frame and the pin connection part are plastic-sealed and leak out of the plastic package. A D-pole electrode is formed, and a carrier D-pole connection surface is provided on the back of the D-pole lead of the frame and the pin connection part; The G-pole lead of the frame is arranged on the same side as the S-pole lead of the frame on the back of the frame carrier. The G-pole lead of the frame is coplanar with the back of the frame carrier. The G-pole lead of the frame leaks out of the plastic package after being plastic-sealed. An S pole electrode is formed, and a carrier G pole connection surface is provided on the back of the G pole lead of the frame; One side of the chip is connected to the S-pole connection surface and the G-pole connection surface of the carrier respectively, and the other side is connected to the Clip chip connection part, and the Clip chip connection part is connected to the D-pole connection surface of the carrier; The size of the chip is larger than the size of the back side of the frame carrier; A Clip heat dissipation copper sheet is provided on the Clip chip connection part, and the upper surface and side surfaces of the Clip heat dissipation copper sheet leak out of the plastic package to form a Clip heat dissipation surface; The Clip chip connection part and the chip are both plastic-sealed in the plastic package body. 2. The double-sided heat dissipation packaging structure according to claim 1, characterized in that: It also includes solder paste, which includes chip S-pole solder paste, lead D-pole solder paste, chip D-pole solder paste, and chip G-pole solder paste; The S-pole solder paste of the chip connects the S-electrode of the chip and the S-pole connection surface of the carrier to provide an S-pole electrical path; The D-pole solder paste of the lead connects the chip and the D-pole connection surface of the carrier; The D-pole solder paste of the chip connects the D-electrode of the chip and the Clip chip connection part, electrically transmits the D-electrode to the Clip copper sheet, and provides an electrical path for the D-electrode; The G-electrode solder paste connects the G-electrode of the chip and the G-electrode connection surface of the carrier to provide a G-electrode electrical path. 3. The double-sided heat dissipation packaging structure according to claim 1 or 2, characterized in that: The Clip chip connection part and the Clip heat dissipation copper sheet are connected through transition fillets. Clip slots are provided on both sides of the Clip heat dissipation copper sheet. During the packaging process, the Clip heat dissipation copper sheet is packaged in a plastic package. The upper surface of the Clip heat dissipation copper sheet is exposed through grinding to form a Clip heat dissipation surface, and the side surface of the Clip heat dissipation copper sheet is exposed out of the plastic package through cutting. 4. The double-sided heat dissipation packaging structure according to claim 1, characterized in that: A downward frame carrier step is provided on the back side of the frame carrier, and the back side of the frame carrier step forms the S-pole connection surface of the carrier; A downward pin connection step is provided on the peripheral side of the pin connection part, and the back side of the pin connection part step forms the D-pole connection surface of the carrier; A downward G-pole lead step is provided on the peripheral side of the G-pole lead of the frame, and the back surface of the G-pole lead step forms the G-pole connection surface of the carrier. 5. The double-sided heat dissipation packaging structure according to claim 1, characterized in that: The Clip chip connection part is provided with a Clip chip connection surface, and the Clip chip connection surface is provided with a Clip chip connection surface fillet. 6. The double-sided heat dissipation packaging structure according to claim 5, characterized in that: A Clip lead connection part is provided at one end of the Clip chip connection part, and a Clip chip connection surface fillet is provided on the Clip lead connection part. 7. The double-sided heat dissipation packaging structure according to claim 6, characterized in that: A Clip step is provided between the Clip chip connection part and the Clip lead connection part, and a groove is formed at the position of the Clip step. 8. The double-sided heat dissipation packaging structure according to any one of claims 4 to 7, characterized in that: The number of S-pole leads of the frame is 3, and the three S-pole leads of the frame are equally spaced; The number of D-pole leads of the frame is 4, and the four D-pole leads of the frame are equally spaced. 9. The double-sided heat dissipation packaging structure according to claim 8, characterized in that: The distance between the Clip heat dissipation surface and the product outline is 0.1mm. 10. A method for preparing a double-sided heat dissipation packaging structure, used to prepare the double-sided heat dissipation packaging structure according to any one of claims 1 to 9, characterized in that it includes the following steps: The lead frame is obtained through the etching process; The wafer is thinned and diced, and the MOS tube is flip-chip mounted on the diced wafer. The D-pole area of the chip is copper-plated. After the wafer is mounted, Clip heat-dissipating copper sheets are mounted; The Clip heat dissipation copper sheet is vacuum reflowed after being patched, and then the residue of solder paste volatiles is cleaned; Apply film to the back of the frame carrier, clean it before plastic sealing, plastic seal the product, and post-cure after plastic sealing; After post-curing, hot boiling is performed to soften, and overflow is removed. After softening, electroplating is performed. After electroplating, baking is performed. After baking, the product is ground to remove Clip heat dissipation copper sheets; After the Clip heat dissipation copper sheet is leaked, it is printed, then cut and separated. After cutting into individual products, the product is tested. After passing the test, it is packaged and stored in the warehouse.