Packaging structure of vehicle gauge grade TO-247PLUS internal insulation series

Abstract

The invention discloses a vehicle gauge level TO-247PLUS internal insulation series packaging structure which comprises an internal structure and a shell, the internal structure comprises a metal substrate, a heat dissipation plate and a ceramic chip, the ceramic chip and the heat dissipation plate are connected through solder paste high-temperature sintering, a plurality of pins are welded to one side of the metal substrate, and the metal substrate and the heat dissipation plate are connected through solder paste high-temperature sintering. A multi-base guide seat is attached to the top of the metal substrate, and the upper frame is used for electroplating of the heat dissipation plate and is integrally connected to one side of the heat dissipation plate. According to the packaging structure of the vehicle gauge grade TO-247PLUS internal insulation series, a product is formed through high-temperature sintering, so that a chip and a cooling fin of the product can be completely insulated, the insulating performance is effectively improved, meanwhile, the use of external components is reduced, the packaging complexity and cost are reduced, and through the arrangement of the upper frame integrally connected with the cooling plate, the packaging efficiency is improved. And after the product is plastically packaged, the heat dissipation plate can be electroplated, so that the reliability and the stability of the product are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of power semiconductor packaging, and in particular to a packaging structure of an automotive-grade TO-247PLUS internal insulation series. Background Art

[0002] With the rapid development of the new energy vehicle industry, the requirements for power semiconductor packaging technology are becoming increasingly higher. The packaging technology of the automotive-grade TO-247 internal insulation series will develop towards higher power density, higher reliability, and lower thermal resistance in the future. At the same time, with the advancement of material science and manufacturing processes, this packaging technology will continue to be optimized and innovated to meet the sustainable development needs of the new energy vehicle industry.

[0003] In the process of implementing the present invention, the inventors found that there are at least the following problems in the prior art:

[0004] The current automotive-grade TO-247 internal insulation series packages usually use insulating ceramic sheets and thermal grease for external insulation. However, this method has cumbersome processing procedures and a relatively large overall thermal resistance. In addition, due to the limitations of the packaging insulation effect, the types of chips that can be loaded are often restricted.

[0005] Therefore, the above technical problems need to be solved. Summary of the invention

[0006] In order to overcome the deficiencies of the prior art, the present invention proposes an automotive-grade TO-247PLUS internal insulation series packaging structure to solve the problems raised in the above background technology.

[0007] In order to solve the above technical problems, the basic technical solution proposed by the present invention is:

[0008] A packaging structure of an automotive-grade TO-247PLUS internal insulation series, including an internal structure and a shell for packaging the internal structure.

[0009] The internal structure includes a metal substrate and a heat sink that are arranged in parallel on the upper and lower sides, and a ceramic sheet placed between the two. The ceramic sheet and the heat sink are connected by high-temperature sintering of solder paste. A plurality of pins are welded on one side of the metal substrate. A multi-base guide seat for mounting a plurality of chips is attached to the top of the metal substrate, and the plurality of chips are electrically connected to the plurality of pins through a plurality of bonding wires.

[0010] The invention also comprises an upper frame which is used for electroplating the heat dissipation plate and is integrally connected to one side of the heat dissipation plate.

[0011] Furthermore, it also includes a lower frame for assembling the internal structure and integrally connected to the outside of the plurality of pins.

[0012] Furthermore, a plurality of heat sinks may be arranged at the bottom of the upper frame, and the plurality of heat sinks are evenly distributed at equal distances along the length direction of the upper frame.

[0013] Furthermore, a plurality of the pins are arranged in groups on one side of the metal substrate, a plurality of pin groups can be arranged in the lower frame, and the plurality of pin groups are evenly distributed at equal distances along the length direction of the lower frame.

[0014] The automotive-grade TO-247PLUS internal insulation series packaging is an optimization and innovation based on the traditional TO-247 package. It uses internal insulating ceramic sheet insulation combined with high-temperature sintering molding, as well as an electroplatable heat sink. It not only simplifies the process, but also reduces thermal resistance, thereby improving the overall power density and performance.

[0015] The beneficial effects of the present invention are:

[0016] 1. Use internal insulating ceramic sheets for insulation, and form the product through high-temperature sintering, so that the chip and heat sink of the product can be completely insulated, effectively improving the insulation performance, while reducing the use of external components, reducing packaging complexity and cost;

[0017] 2. The high-temperature sintering molding method improves the stability and heat dissipation efficiency of the packaging structure and further reduces the thermal resistance;

[0018] 3. Due to the optimization of the packaging structure, the automotive-grade TO-247PLUS internal insulation series package can install two or more high-power chip combinations, so that the product can achieve diversification and realize various functions while improving the power density;

[0019] 4. By providing an upper frame integrally connected to the heat sink, the heat sink can be electroplated after the product is plastic-sealed, which not only improves the overall aesthetics of the product, but also enhances the corrosion resistance and mechanical strength of the heat sink, and improves the reliability and stability of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a front structural schematic diagram of an embodiment of the present invention;

[0021] Figure 2 It is a schematic diagram of the back structure of an embodiment of the present invention;

[0022] Figure 3 It is a structural schematic diagram of the internal structure of the present invention;

[0023] Figure 4 It is a schematic diagram of the split structure of the internal structure of the present invention;

[0024] Figure 5 It is a structural schematic diagram of another embodiment of the present invention;

[0025] Figure 6 It is a structural schematic diagram of another embodiment of the present invention;

[0026] Figure 7 It is a framework diagram of the present invention;

[0027] Figure 8 It is an assembly diagram of the internal structure of the present invention;

[0028] Description of reference numerals:

[0029] 100. Internal structure;

[0030] 110, metal substrate; 120, heat sink; 130, ceramic sheet; 140, solder paste; 150, pin; 160, multi-base guide; 170, bonding wire;

[0031] 1210, upper frame;

[0032] 1510, lower frame;

[0033] 200. Shell. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] See also Figure 1-8 The present invention provides a technical solution: a packaging structure of an automotive-grade TO-247PLUS internal insulation series, including an internal structure 100 and a shell 200 for packaging the internal structure 100, the internal structure 100 includes a metal substrate 110 and a heat sink 120 that are distributed in parallel in the upper and lower directions, and a ceramic sheet 130 padded between the two, the ceramic sheet 130 and the heat sink 120 are connected by high-temperature sintering of solder paste 140, a plurality of pins 150 are welded on one side of the metal substrate 110, a multi-base guide seat 160 for mounting a plurality of chips is bonded to the top of the metal substrate 110, and the plurality of chips are electrically connected to the plurality of pins 150 through a plurality of bonding wires 170, and also includes an upper frame 1210 for electroplating the heat sink 120 and integrally connected to one side of the heat sink 120.

[0036] Based on the above-mentioned structural setting, the packaging structure of the automotive-grade TO-247PLUS internal insulation series is composed of an internal structure 100 and a shell 200, wherein the internal structure 100 is composed of a multi-base guide seat 160 that can be bonded to several chips, as well as a metal substrate 110, a ceramic sheet 130, solder paste 140, a heat sink 120, several pins 150 and several bonding wires 170, and the multi-base guide seat 160, the metal substrate 110, the ceramic sheet 130, the solder paste 140 and the heat sink 120 are stacked in sequence from top to bottom.

[0037] For housing 200:

[0038] To ensure electrical isolation between chips and between chips and external circuits, this application uses encapsulation resin for external encapsulation. The encapsulation resin has good insulation properties and can effectively isolate electrical components to prevent current leakage and short circuit. In addition, Figure 1 and Figure 2 As shown, it is an embodiment of the housing 200 of the present application. Figure 5 As shown, another embodiment of the shell 200 of the present application is shown. By opening a hole in the shell 200, the heat inside the package can be more easily conducted through air convection or direct contact with external heat dissipation elements, such as heat sinks, water cooling plates, etc., thereby effectively reducing the operating temperature inside the package and improving the reliability and service life of the device. In addition, the heat dissipation path can be optimized. The hole design can reduce thermal resistance, so that heat can be transferred from the chip to the external environment more quickly. Especially in high power density applications, this design is crucial to maintaining the device within the allowable operating temperature range.

[0039] In the internal structure 100:

[0040] As the core component of the package, the chip is responsible for the conversion and control of electric energy. The present application adopts a multi-chip integrated layout on the multi-base guide seat 160, that is, the packaging structure of the automotive-grade TO-247PLUS internal insulation series can support the integration of multiple chips in one package. These chips can be power chips, control chips or other functional chips to achieve more complex circuit functions and higher power density to meet diversified needs. The multi-chip layout helps to achieve a modular design of the package, that is, to integrate different functional modules in one package, reducing the complexity and cost of external connections.

[0041] The metal substrate 110 serves as a heat conduction and electrical connection path inside the package. The metal substrate 110 may be a copper substrate with high thermal conductivity, which can significantly reduce the thermal resistance inside the package and improve the heat dissipation efficiency. The chip is connected to the metal substrate 110 through a bonding wire 170, and the pin 150 is welded on one side of the metal substrate 110 to achieve connection with an external circuit. At the same time, the metal substrate 110 serves as a heat conduction path between the chip and the pin 150, and is responsible for quickly conducting the heat generated by the chip and dispersing it to the external heat dissipation system.

[0042] The ceramic sheet 130 is built into the package body and adopts an aluminum nitride substrate or an aluminum oxide substrate. The ceramic sheet 130 is used as an inner packaging structure of the inner insulation series to ensure electrical isolation between the chip and the external circuit, and at the same time buffer the thermal stress generated by the difference in thermal expansion coefficient between the chip and the metal substrate 110. The inner insulation design ensures the safety and reliability of the package in high-voltage and high-power applications, helps prevent electrical breakdown, short circuit and other faults, and improves the overall performance and service life of the package;

[0043] The solder paste 140 is mainly used to achieve a stable connection between the ceramic sheet 130 and the heat sink 120 through high-temperature sintering. The solder paste 140 will melt during the high-temperature sintering process and form a metallurgical bond with the surface of the ceramic sheet 130 and the heat sink 120, thereby enhancing the strength of the entire connection structure. The improvement in the structural strength can ensure that the connection point is not prone to breakage or loosening when subjected to external forces. Compared with traditional connection methods, such as welding or mechanical connection, the high-temperature sintering of the solder paste 140 to connect the ceramic sheet 130 and the heat sink 120 has the advantages of simple process and convenient operation. This connection method can reduce processing steps and production costs and improve production efficiency. In addition, the main function of the heat sink 120 is to dissipate heat, while the ceramic sheet 130 has excellent thermal conductivity. The ceramic sheet 130 and the heat sink 120 are tightly connected together by high-temperature sintering of the solder paste 140 to form an efficient heat dissipation channel.

[0044] The heat sink 120 is the core heat dissipation part in the TO-247PLUS package. It is made of copper material with high thermal conductivity and is connected to the internal ceramic sheet 130 through a high-temperature sintering process of solder paste 140. It is not only responsible for quickly conducting the heat generated by the chip, but also serves as an interface for connecting to an external heat dissipation system, such as a radiator or a cooling fan. In addition, the heat sink 120 in the present application has an obvious advantage over the traditional heat dissipation structure in that the electroplating of the heat sink 120 can be achieved in the process link. Specifically, an upper frame 1210 integrally connected to the heat sink 120 is provided to facilitate the electroplating process and subsequent processing. After the electroplating is completed, the upper frame 1210 is cut off to remove the electroplated The heat sink 120 is separated from the upper frame 1210, and the heat sink 120 after electroplating has obvious advantages, such as increased mechanical strength and hardness. The electroplating layer can increase the mechanical strength and hardness of the back of the heat sink 120, improve its wear resistance and pressure resistance, make the product more stable and reliable during use, and increase the corrosion resistance. The electroplating forms a uniform and dense protective layer on the back of the heat sink 120, which can effectively isolate air, moisture and other corrosive media, thereby slowing down the oxidation and corrosion rate of copper, extending the service life of the product, and at the same time, improving the aesthetics. The electroplating layer can make the back of the heat sink 120 present a more uniform and bright appearance, improving the overall aesthetics of the product.

[0045] The pins 150 are the key part of the package body connected to the external circuit. They are connected to the metal substrate 110 through a welding process and extend outward for external circuit connection. The number, layout and size of the pins 150 can be determined according to the design and application requirements of the package. Usually, 3 or 4 pins 150 are included to meet different circuit requirements, such as Figure 1 and Figure 6 As shown, there are respectively an embodiment of 4 pins 150 and an embodiment of 3 pins 150. Specifically, in the welding process of the pins 150, a high-wettability and high-fluidity welding material, such as SAC305 welding material, is selected to ensure the quality and reliability of the welding layer, and to form a stable electrical and mechanical connection between the metal substrate 110 and the pins 150;

[0046] The bonding wire 170 is used to connect the chip and the pin 150, improve the current capacity and increase the reliability of the product. The electrodes on the chip are connected to the pins on the metal substrate 110 by gold wire or aluminum wire through wire bonding technology, ensuring the electrical connection between the chip and the external circuit.

[0047] like Figure 7 and Figure 8 As shown, the specific process flow is:

[0048] Internal packaging: The ceramic sheet 130 is packaged on the back of the metal substrate 110 to form an internal insulation layer, and the ceramic sheet 130 and the heat sink 120 are connected by high-temperature sintering of the solder paste 140;

[0049] Chip installation: The selected chips are mounted on the designated position of the multi-base guide 160 on the metal substrate 110 through conductive glue or solder;

[0050] Wire bonding: soldering the pins 150 to the metal substrate 110 and connecting the electrodes on the chip to the pins 150 using bonding wires 170;

[0051] External packaging: After completing the internal structure 100 and circuit connection, external packaging is performed, and the packaging resin is injected into the package body to cover the chip and the bonding wire 170. The fluidity and curing time of the resin are controlled to ensure the integrity and sealing of the package body. The packaging resin is then cured at an appropriate temperature, and the package body is then trimmed and polished to ensure that it has a smooth and defect-free appearance.

[0052] Electroplating: Electroplating is performed on the back of the heat sink 120 . After the electroplating is completed, the upper frame 1210 integrally connected to the heat sink 120 and the lower frame 1510 integrally connected to the pins 150 are punched out.

[0053] The packaging structure of the automotive-grade TO-247PLUS internal insulation series uses an internal insulating ceramic sheet 130 for insulation, and the product is formed through high-temperature sintering, so that the chip and the heat sink 120 of the product can be completely insulated, effectively improving the insulation performance, while reducing the use of external components, reducing the complexity and cost of packaging, and at the same time, through the high-temperature sintering molding method, the stability and heat dissipation efficiency of the packaging structure are improved, and the thermal resistance is further reduced. Due to the optimization of the packaging structure, the automotive-grade TO-247PLUS internal insulation series packaging can install two or more high-power chip combinations, so that the product can achieve diversification and realize various functions while improving the power density. In addition, by providing an upper frame 1210 integrally connected to the heat sink 120, the heat sink 120 can be electroplated after the product is plastic-sealed, which not only improves the overall aesthetics of the product, but also enhances the corrosion resistance and mechanical strength of the heat sink 120, thereby improving the reliability and stability of the product.

[0054] Furthermore, it also includes a lower frame 1510 for assembling the internal structure 100 and integrally connected to the outside of the plurality of pins 150. The lower frame 1510 is arranged outside the plurality of pins 150, which is helpful for the overall assembly of the plurality of pins 150 for a single product.

[0055] Furthermore, a plurality of heat dissipation plates 120 may be disposed at the bottom of the upper frame 1210 , and the plurality of heat dissipation plates 120 may be evenly distributed at equal distances along the length direction of the upper frame 1210 .

[0056] Furthermore, a plurality of pins 150 are arranged in groups on one side of the metal substrate 110 , and a plurality of pin groups may be disposed in the lower frame 1510 , and the plurality of pin groups are evenly distributed at equal distances along the length direction of the lower frame 1510 .

[0057] Among them, a plurality of heat sinks 120 are respectively arranged in the upper frame 1210 and a plurality of pin groups are respectively arranged in the lower frame 1510. The plurality of heat sinks 120 correspond to the plurality of pin groups one by one, respectively, so as to facilitate batch processing in the product production process.

[0058] According to the disclosure and teaching of the above description, those skilled in the art to which the present invention belongs may also make changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the present invention should also fall within the scope of protection of the claims of the present invention. In addition, although some specific terms are used in this specification, these terms are only for the convenience of description and do not constitute any limitation to the present invention.

Claims

1. A packaging structure of the automotive grade TO-247PLUS internal insulation series, characterized by: It comprises an internal structure (100) and a shell (200) for encapsulating the internal structure (100); The internal structure (100) comprises a metal substrate (110) and a heat sink (120) which are arranged in parallel in an upper and lower manner, and a ceramic sheet (130) which is placed between the two. The ceramic sheet (130) and the heat sink (120) are connected by high-temperature sintering of solder paste (140). A plurality of pins (150) are welded on one side of the metal substrate (110). A multi-base guide seat (160) for mounting a plurality of chips is bonded to the top of the metal substrate (110), and the plurality of chips are electrically connected to the plurality of pins (150) via a plurality of bonding wires (170). It also includes an upper frame (1210) for electroplating the heat dissipation plate (120) and integrally connected to one side of the heat dissipation plate (120).

2. The packaging structure of the automotive grade TO-247PLUS internal insulation series according to claim 1 is characterized in that: It also includes a lower frame (1510) for assembling the internal structure (100) and integrally connected to the outside of a plurality of pins (150).

3. The packaging structure of the automotive grade TO-247PLUS internal insulation series according to claim 1 is characterized in that: A plurality of heat sinks (120) may be arranged at the bottom of the upper frame (1210), and the plurality of heat sinks (120) are evenly distributed at equal distances along the length direction of the upper frame (1210).

4. The packaging structure of the automotive grade TO-247PLUS internal insulation series according to claim 2 is characterized in that: A plurality of the pins (150) are arranged in groups on one side of the metal substrate (110); a plurality of pin groups may be arranged in the lower frame (1510), and the plurality of pin groups are evenly distributed at equal distances along the length direction of the lower frame (1510).

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