A packaging structure of a power module

Abstract

The application relates to the packaging technical field, in particular to a packaging structure of a power module, which comprises a middle-through shell, a base plate and a cover plate located at two opening sides of the shell; wherein a plurality of pin members are embedded in the shell, the pin members are in a bending structure, and one end of the pin members extends into a through hole of the shell, and the other end of the pin members extends to the outside of the shell; in the application, the pin members are embedded in the shell, compared with the traditional pin member externalization and plastic packaging mode, the all-metal welding mode in the application greatly improves the overall airtightness of the power module after welding, meanwhile, the main body adopts a ceramic material to realize more excellent heat dissipation and corrosion prevention effect, and effectively enhances the applicability and service life of the power module.

Description

Technical Field

[0001] This invention relates to the field of packaging technology, and more particularly to a packaging structure for a power module. Background Technology

[0002] Power semiconductor modules, also known as power electronic modules, are designed to operate at relatively high voltages. Semiconductor devices come in many packaging types, with increasingly advanced technologies ranging from chip-level packaging to system-on-a-chip (SoC) and then to wafer-level packaging. Packaging is essential and crucial for chips. The package is the outer shell that houses the semiconductor integrated circuit chip, serving not only to protect the chip and enhance its thermal conductivity, but also as a bridge connecting the chip's internal components with external circuits and providing standard functionality.

[0003] For example, Chinese Patent Publication No. CN103928447B discloses a high-power fully hermetically sealed semiconductor module packaging structure, including a heat-conducting base plate, a metal sealing frame, an internal ceramic substrate, connecting pillars, a semiconductor chip, circuit connecting metal wires, a ceramic cap, a small cap, and pins. The metal sealing frame, the heat-conducting base plate, the internal ceramic substrate, and the semiconductor chip are sequentially welded together. The two ends of the circuit connecting metal wires are bonded to the semiconductor chip and the internal ceramic substrate respectively by conventional ultrasonic bonding equipment or a bonding device that combines heating and ultrasonic bonding to form a circuit path.

[0004] In this technical solution, it can be seen that the pins are soldered onto the ceramic cover and protected by a plastic shell. The pins and the shell are connected by a plug-in method. It can be seen that the overall structure has poor airtightness, and the use of a plastic shell for external sealing results in poor service life and applicability. Summary of the Invention

[0005] The purpose of this invention is to address the aforementioned shortcomings in the prior art by proposing a packaging structure for a power module.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] Design a power module packaging structure, including a housing that runs through the middle and a substrate and a cover plate located on two opening sides of the housing;

[0008] The housing contains a plurality of pins, each pin having a bent structure, with one end extending into a through hole in the housing and the other end extending to the outside of the housing.

[0009] Furthermore, it also includes a connector located between the substrate and the housing.

[0010] Furthermore, the connector has a stepped hole in the middle, and the substrate is in a stepped shape that matches the stepped hole, so as to embed the substrate into the connector.

[0011] Furthermore, an embedding structure is provided between the connector and the cover plate and the outer shell, so that at least a portion of the connector and the cover plate can be built into the outer shell through the embedding structure.

[0012] Furthermore, the embedded structure includes:

[0013] An outer ring groove is formed at the edge of the connector and cover plate near the side end of the base plate, so that the connector and cover plate form a protrusion at the outer ring groove.

[0014] The outer casing has inner annular grooves on its two inner edges, and the outer annular grooves can be inserted into the inner annular grooves.

[0015] Furthermore, the substrate is a metal plate, on which at least one set of chips is bonded, wherein each pin of the chip is electrically connected to the pin assembly via a lead wire.

[0016] Furthermore, the pin extends from the free end of the housing in a bent structure that covers the outside of the cover plate.

[0017] Furthermore, the outer shell and cover plate are ceramic parts, and the outer shell and cover plate are sealed and fixed by metallization welding.

[0018] Furthermore, the connector is a ceramic ring, and the substrate, connector, and shell are encapsulated and fixed together by metallization welding.

[0019] Furthermore, the pins are provided in four groups, and are symmetrically arranged in pairs on the two horizontal sides of the housing.

[0020] The packaging structure of the power module proposed in this invention has the following advantages: By embedding the pins inside the housing, compared with the traditional method of external pins and plastic packaging, the fully metallized welding method in this application greatly improves the overall airtightness of the power module after welding. At the same time, the use of ceramic material for the main body can achieve better heat dissipation and corrosion resistance, effectively enhancing the applicability and service life of the power module. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of the present invention;

[0022] Figure 2 This is a cross-sectional view of the invention in its exploded state.

[0023] In the figure: 1. Outer shell; 11. Inner ring groove; 2. Substrate; 3. Cover plate; 4. Pin; 5. Connector; 51. Outer ring groove. Detailed Implementation

[0024] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0025] Reference Figure 1-2 A power module packaging structure includes a housing 1 that runs through the middle and a substrate 2 and a cover plate 3 located on two opening sides of the housing 1.

[0026] The outer casing 1 contains a number of pins 4. The pins 4 are bent and one end extends into the through hole of the outer casing 1. The other end of the pins 4 extends to the outside of the outer casing 1. In the embodiment of the present invention, four sets of pins 4 are provided and are symmetrically arranged in pairs on the two horizontal sides of the outer casing 1.

[0027] Furthermore, the present invention also includes a connector 5, which is located between the substrate 2 and the outer shell 1. The connector 5 is used to connect and fix the substrate 2 and can provide protection to the outer side of the substrate 2.

[0028] Specifically, the connector 5 has a stepped hole in the middle, and the substrate 2 is in a stepped shape that matches the stepped hole, so that the substrate 2 can be embedded in the connector 5. Through the structural design in this invention, the substrate 2 is embedded into the connector 5, which not only protects the side of the substrate 2, but also facilitates the connection of the outer shell 1.

[0029] Furthermore, in this invention, the connector 5 and the cover plate 3 are both provided with an embedding structure between them and the outer shell 1, so that at least a portion of the connector 5 and the cover plate 3 can be built into the outer shell 1 through the embedding structure.

[0030] More specifically, the aforementioned embedded structure includes:

[0031] An outer ring groove 51 is formed at the edge of the connector 5 and the cover plate 3 near the side end of the substrate 2, so that the connector 5 and the cover plate 3 form a protrusion at the outer ring groove 51.

[0032] Inner annular grooves 11 are formed on the two inner edges of the outer casing 1, and outer annular grooves 51 can be inserted into the inner annular grooves 11.

[0033] Those skilled in the art will understand that the plug-in design of this structure facilitates the provision of welding positions for metallization welding during subsequent assembly, and the interlocking structure has higher strength and greater stability after welding.

[0034] Furthermore, the substrate 2 is a metal plate, on which at least one set of chips is bonded. The pins of the chips are electrically connected to the lead element 4 via leads. In this embodiment, the substrate 2 can be a copper plate. Of course, in other embodiments, the substrate 2 can also be a silicon carbide plate. The specific choice can be made by those skilled in the art based on the specific heat dissipation requirements.

[0035] Furthermore, the pin 4 extends from the free end of the housing 1 in a bent structure that covers the outside of the cover plate 3. In this embodiment, the pin 4 adopts a bent structure design, firstly to save the space occupied by the pin, and secondly to avoid the problem of bending under force in the vertical design.

[0036] It should be noted that in this invention, the outer shell 1 and the cover plate 3 are ceramic parts. The outer shell 1 and the cover plate 3 are sealed and fixed by metallization welding. The metallization welding method involves coating a metal layer that is firmly bonded to the ceramic surface, and then fixing and sealing it by welding. This method is a conventional technique in the field and will not be described in detail here.

[0037] Furthermore, similarly, the connector 5 is a ceramic ring, and the substrate 2, connector 5 and shell 1 are encapsulated and fixed together by metallization welding. By adopting metallization welding, the overall airtightness of the entire power module after welding is greatly improved. At the same time, the main body is made of ceramic material, which can achieve better heat dissipation and corrosion resistance, effectively enhancing the applicability and service life of the power module.

[0038] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A packaging structure for a power module, characterized in that, It includes a shell that runs through the middle and a base plate and a cover plate located on both sides of the opening of the shell; The housing includes several embedded pins, each pin having a bent structure with one end extending into a through hole in the housing and the other end extending to the outside of the housing. It also includes a connector located between the substrate and the housing, with a stepped hole in the middle. The substrate is stepped to fit the stepped hole, allowing it to be embedded in the connector. An embedding structure is provided between the connector and the cover plate and the housing, allowing at least a portion of the connector and cover plate to be housed within the housing. The embedding structure includes: An outer ring groove is formed at the edge of the connector and cover plate near the side end of the base plate, so that the connector and cover plate form a protrusion at the outer ring groove. The outer casing has inner ring grooves on its two inner edges, and the outer ring groove can be inserted into the inner ring groove. The outer casing and the cover plate are ceramic parts, and the outer casing and the cover plate are encapsulated and fixed by metallization welding. The connector is a ceramic ring, and the substrate, connector and outer casing are encapsulated and fixed by metallization welding.

2. The packaging structure of a power module according to claim 1, characterized in that: The substrate is a metal plate, on which at least one set of chips are bonded, wherein each pin of the chip is electrically connected to the pin assembly via a lead wire.

3. The packaging structure of a power module according to claim 1, characterized in that: The pins extend from the free end of the housing in a bent structure that covers the outside of the cover plate.

4. The packaging structure of a power module according to claim 1, characterized in that: The pins are arranged in four groups, and are symmetrically arranged in pairs on the two horizontal sides of the housing.

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