A package structure for a silicon carbide device

Abstract

The utility model relates to the field of semiconductor packaging, concretely to a packaging structure of silicon carbide device, including first metal shell and second metal shell, the first metal shell is fixedly connected with the metal frame, the bottom of second metal shell is set in the top of metal frame, and is provided with the forming cavity between first metal shell and metal frame, is provided with plastic filling piece in forming cavity, and first metal shell, second metal shell and metal frame form sealing element through plastic filling piece, and the sealing element is filled with nitrogen, through the cooperation setting of first substrate, second substrate, third substrate, storage pipe and extension pole, the heat of chip is transferred to first metal shell through first substrate, is transferred to second metal shell through second substrate, third substrate, forms bidirectional heat dissipation channel, ensures that device still can quickly dissipate heat under high temperature, high frequency work scene, guarantees power density and operating stability.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor packaging technology, specifically to a packaging structure for a silicon carbide device. Background Technology

[0002] Silicon carbide (SiC), as a representative of third-generation wide-bandgap semiconductor materials, possesses excellent material properties: its bandgap is three times that of silicon, its breakdown field strength is ten times that of silicon, its thermal conductivity is three times that of silicon, and its electron saturation drift velocity is twice that of silicon. These superior material properties enable SiC devices to operate at higher temperatures, voltages, and frequencies, bringing higher power density, efficiency, and reliability to power electronic systems. With the rapid growth in demand for high-performance power electronic devices in fields such as new energy vehicles, renewable energy, 5G communications, and industrial automation, SiC devices are increasingly widely used in power conversion systems.

[0003] Chinese patent CN221486482U discloses a novel high-temperature resistant silicon carbide device packaging structure. It replaces the housing with a metal material, which enables it to withstand high temperatures and dissipate heat quickly. Furthermore, the chip and pins are detachable, allowing for quick replacement and maintenance after opening the cover, thus increasing convenience.

[0004] In the above scheme, although a metal shell is used to accelerate the heat dissipation of silicon carbide devices, the lack of a thermally conductive structure between the chip and the metal shell, relying solely on air for heat conduction, results in low heat dissipation efficiency. Furthermore, the gap between the chip and the metal shell leads to poor stability of the chip within the metal shell.

[0005] Therefore, this invention provides a packaging structure for silicon carbide devices to solve the above problems. Utility Model Content

[0006] In order to overcome the shortcomings of the prior art, this utility model provides a packaging structure for silicon carbide devices to solve the problems of low heat dissipation efficiency due to the lack of a heat-conducting structure between the chip and the metal casing, relying solely on air for heat conduction, and poor stability of the chip within the metal casing due to the gap between the chip and the metal casing.

[0007] To achieve the above objectives, the technical solution adopted by this utility model is as follows: A packaging structure for a silicon carbide device includes a first metal shell and a second metal shell. A metal frame is fixedly connected to the first metal shell. The bottom end of the second metal shell is sleeved on the top of the metal frame. A molding cavity is provided between the first metal shell and the metal frame. A plastic filler is provided in the molding cavity. The first metal shell, the second metal shell, and the metal frame form a seal through the plastic filler. The seal is filled with nitrogen gas.

[0008] The first metal shell contains a silicon carbide chip structure, and the silicon carbide chip structure is equipped with a pin. One end of the pin passes through the metal frame and the plastic filler and extends to the outside of the seal. The seal contains a support component for limiting the position of the silicon carbide chip structure.

[0009] Preferably, a first metal plate is fixedly connected to the first metal shell, and a second metal plate is fixedly connected to the second metal shell.

[0010] Preferably, the inner wall of the metal frame is provided with a positioning groove, and a positioning block is fixedly connected to the second metal shell, and the positioning block matches the positioning groove.

[0011] Preferably, a sealing groove is provided at the top of the metal frame, a sealing gasket is placed in the sealing groove, and the sealing gasket is located between the sealing groove and the second metal shell.

[0012] Preferably, a limiting block is fixedly connected to the pin, the limiting block is located inside the first metal shell, and the limiting block abuts against the inner wall of the first metal shell.

[0013] Preferably, the support assembly includes a first substrate installed inside a first metal shell, the bottom end of the silicon carbide chip structure is installed on the first substrate, a second substrate is disposed above the silicon carbide chip structure, a third substrate is fixedly connected to the inner wall of the metal frame, a connecting mechanism is disposed on the third substrate, and the second substrate is installed on the third substrate through the connecting mechanism.

[0014] Preferably, the connecting mechanism includes a fixed bracket fixedly connected to the third substrate, an adjusting screw threadedly connected to the fixed bracket, a screw block fixedly connected to one end of the adjusting screw, and the other end of the adjusting screw passing through the fixed bracket and rotatably connected to the second substrate, and the adjusting screw being threadedly connected to the fixed bracket.

[0015] Preferably, the connecting mechanism further includes a storage tube fixedly connected to the third substrate, the bottom surface of the storage tube being slidably connected to an extension rod, and the bottom end of the extension rod being fixedly connected to the second substrate.

[0016] Preferably, a protective frame is fixedly connected inside the first metal shell, and the protective frame wraps around the outside of the three-layer structure formed by the first substrate, the silicon carbide chip structure, and the second substrate.

[0017] The beneficial effects of this utility model are as follows: 1. Through the coordinated arrangement of the first substrate, the second substrate, the third substrate, the receiving tube and the extension rod, the heat of the chip is transferred to the first metal shell through the first substrate, and to the second metal shell through the second substrate and the third substrate, forming a bidirectional heat dissipation channel. This ensures that the device can quickly dissipate heat in high-temperature and high-frequency operating scenarios, thus guaranteeing power density and operational stability.

[0018] 2. By setting up support components, the first substrate provides a solid bottom support for the chip, and the second substrate can be precisely pressed onto the top of the chip through the threaded transmission of the adjusting screw. With the guiding effect of the storage tube and extension rod, the chip installation gap is effectively eliminated, and displacement caused by vibration during device operation is avoided. The protective frame completely wraps the three-layer structure formed by the substrate and the chip, forming a physical protective barrier, reducing the impact of external force on the chip, significantly improving the installation stability of silicon carbide chips in the packaging structure, and reducing the risk of connection failure caused by chip shaking. Attached Figure Description

[0019] Figure 1 This is a perspective view of the present invention.

[0020] Figure 2 This is an exploded view of the present invention.

[0021] Figure 3 This is a cross-sectional view of the present invention.

[0022] Figure 4 This utility model Figure 3 An enlarged schematic diagram of the structure at point A in the middle.

[0023] In the diagram: 1. First metal shell; 2. First metal plate; 3. Second metal shell; 4. Second metal plate; 5. Metal frame; 6. Molding cavity; 7. Plastic filler; 8. First substrate; 9. Silicon carbide chip structure; 10. Pin; 11. Limiting block; 12. Sealing groove; 13. Positioning groove; 14. Sealing gasket; 15. Positioning block; 16. Second substrate; 17. Third substrate; 18. Storage tube; 19. Extension rod; 20. Protective frame; 21. Fixing bracket; 22. Adjusting screw; 23. Tightening block. Detailed Implementation

[0024] The following will refer to the attached reference. Figures 1 to 4 The various embodiments of this utility model will be described in detail below. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of this utility model and are not intended to limit the scope of protection of this utility model.

[0025] A packaging structure for a silicon carbide device includes a first metal shell 1 and a second metal shell 3. A first metal plate 2 is fixedly connected to the first metal shell 1, and a second metal plate 4 is fixedly connected to the second metal shell 3.

[0026] The first metal plate 2 and the second metal plate 4 both use the same heat-conducting material as the first metal shell 1 and the first metal plate 2, which can be copper or aluminum. The first metal plate 2 and the second metal plate 4 are also provided with round holes to facilitate the fixing of the first metal plate 2 and the second metal plate 4.

[0027] In this embodiment, a metal frame 5 is fixedly connected to the first metal shell 1, the bottom end of the second metal shell 3 is sleeved on the top of the metal frame 5, and a forming cavity 6 is provided between the first metal shell 1 and the metal frame 5. A positioning groove 13 is provided on the inner wall of the metal frame 5, and a positioning block 15 is fixedly connected to the second metal shell 3, and the positioning block 15 matches the positioning groove 13.

[0028] The metal frame 5 can form a enclosure on the first metal shell 1, while the second metal shell 3 covers the top of the metal frame 5. When the second metal shell 3 is installed on the metal frame 5, the positioning block 15 will be inserted into the positioning groove 13 to complete the alignment of the second metal shell 3 and the metal frame 5.

[0029] To further improve the sealing performance of the connection between the second metal shell 3 and the metal frame 5, a sealing groove 12 is provided at the top of the metal frame 5, and a sealing gasket 14 is placed in the sealing groove 12, with the sealing gasket 14 located between the sealing groove 12 and the second metal shell 3.

[0030] With the sealing gasket 14 located at the connection between the second metal shell 3 and the metal frame 5, a limiting barrier is formed, which can effectively prevent external liquids or other debris from entering the first metal shell 1.

[0031] In this embodiment, a plastic filler 7 is provided in the molding cavity 6, and the first metal shell 1, the second metal shell 3 and the metal frame 5 form a seal through the plastic filler 7, and the seal is filled with nitrogen gas.

[0032] After the second metal shell 3 is placed on the metal frame 5, nitrogen is filled into the seal. Then, the plastic filler 7 is formed in the molding cavity 6 between the first metal shell 1 and the second metal shell 3 by injection molding. The connection between the first metal shell 1 and the second metal shell 3 is completed by the plastic filler 7, which effectively improves the sealing between the first metal shell 1 and the second metal shell 3.

[0033] In this embodiment, a silicon carbide chip structure 9 is disposed inside the first metal shell 1. A pin 10 is mounted on the silicon carbide chip structure 9. One end of the pin 10 passes through the metal frame 5 and the plastic filler 7 and extends to the outside of the seal. A limiting block 11 is fixedly connected to the pin 10. The limiting block 11 is located inside the first metal shell 1 and abuts against the inner wall of the first metal shell 1. A support component for limiting the silicon carbide chip structure 9 is disposed inside the seal.

[0034] The limiting block 11 can limit the position of the foot 10 in the seal, and the limiting block 11 can also form a block at the connection between the foot 10 and the metal frame 5.

[0035] In this embodiment, the support component includes a first substrate 8 installed inside the first metal shell 1, the bottom end of the silicon carbide chip structure 9 is installed on the first substrate 8, a second substrate 16 is disposed above the silicon carbide chip structure 9, a third substrate 17 is fixedly connected to the inner wall of the metal frame 5, a connecting mechanism is disposed on the third substrate 17, and the second substrate 16 is installed on the third substrate 17 through the connecting mechanism.

[0036] The silicon carbide chip structure 9 is supported by the first substrate 8. The silicon carbide chip structure 9, the second substrate 16 and the third substrate 17 are all made of ceramic material, which not only has insulation properties but also excellent thermal conductivity, and can conduct the heat generated by the silicon carbide chip structure 9 to the first metal shell 1 and the second metal shell 3 for heat dissipation.

[0037] The connection mechanism includes a fixed bracket 21 fixedly connected to the third substrate 17. An adjusting screw 22 is threadedly connected to the fixed bracket 21. One end of the adjusting screw 22 is fixedly connected to a screw block 23. The other end of the adjusting screw 22 passes through the fixed bracket 21 and is rotatably connected to the second substrate 16. The adjusting screw 22 is threadedly connected to the fixed bracket 21.

[0038] When adjusting the distance between the second substrate 16 and the receiving tube 18, the adjusting screw 22 can be rotated by the screw block 23, and the adjusting screw 22 can be made to rotate spirally on the fixed bracket 21, thereby causing the adjusting screw 22 to drive the second substrate 16 to move, so that the second substrate 16 presses on the silicon carbide chip structure 9, thus completing the limiting protection of the silicon carbide chip structure 9.

[0039] The connecting mechanism also includes a storage tube 18 fixedly connected to the third substrate 17. An extension rod 19 is slidably connected to the bottom surface of the storage tube 18, and the bottom end of the extension rod 19 is fixedly connected to the second substrate 16.

[0040] Both the housing tube 18 and the extension rod 19 are made of ceramic material, which has thermal conductivity and can transfer heat from the second substrate 16 to the third substrate 17. Moreover, the extension rod 19 can guide the movement of the second substrate 16 by sliding on the housing tube 18.

[0041] A protective frame 20 is fixedly connected inside the first metal shell 1. The protective frame 20 wraps around the outside of the three-layer structure formed by the first substrate 8, the silicon carbide chip structure 9, and the second substrate 16. The three-layer structure formed by the first substrate 8, the silicon carbide chip structure 9, and the second substrate 16 is protected by the protective frame 20.

[0042] It should be noted that in the description of this utility model, terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," which indicate direction or positional relationships, are based on the direction or positional relationships shown in the accompanying drawings. These are used merely for ease of description and do not indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0043] Furthermore, it should be noted that, in the description of this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0044] The technical solution of this utility model has been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the protection scope of this utility model is obviously not limited to these specific embodiments. Without departing from the principle of this utility model, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the protection scope of this utility model.

Claims

1. A packaging structure for a silicon carbide device, characterized in that, It includes a first metal shell (1) and a second metal shell (3). A metal frame (5) is fixedly connected to the first metal shell (1). The bottom end of the second metal shell (3) is sleeved on the top of the metal frame (5). A molding cavity (6) is provided between the first metal shell (1) and the metal frame (5). A plastic filler (7) is provided in the molding cavity (6). The first metal shell (1), the second metal shell (3) and the metal frame (5) form a seal through the plastic filler (7). The seal is filled with nitrogen. The first metal shell (1) is provided with a silicon carbide chip structure (9), and a pin (10) is installed on the silicon carbide chip structure (9). One end of the pin (10) passes through the metal frame (5) and the plastic filler (7) and extends to the outside of the seal. The seal is provided with a support component for limiting the position of the silicon carbide chip structure (9).

2. The packaging structure of a silicon carbide device according to claim 1, characterized in that, A first metal plate (2) is fixedly connected to the first metal shell (1), and a second metal plate (4) is fixedly connected to the second metal shell (3).

3. The packaging structure of a silicon carbide device according to claim 1, characterized in that, The inner wall of the metal frame (5) is provided with a positioning groove (13), and a positioning block (15) is fixedly connected to the second metal shell (3), and the positioning block (15) matches the positioning groove (13).

4. The packaging structure of a silicon carbide device according to claim 1, characterized in that, The top of the metal frame (5) is provided with a sealing groove (12), and a sealing gasket (14) is placed in the sealing groove (12), and the sealing gasket (14) is located between the sealing groove (12) and the second metal shell (3).

5. The packaging structure of a silicon carbide device according to claim 1, characterized in that, A limiting block (11) is fixedly connected to the pin (10). The limiting block (11) is located inside the first metal shell (1) and abuts against the inner wall of the first metal shell (1).

6. The packaging structure of a silicon carbide device according to claim 1, characterized in that, The support assembly includes a first substrate (8) installed inside a first metal shell (1), the bottom end of the silicon carbide chip structure (9) is installed on the first substrate (8), a second substrate (16) is provided above the silicon carbide chip structure (9), a third substrate (17) is fixedly connected to the inner wall of the metal frame (5), a connecting mechanism is provided on the third substrate (17), and the second substrate (16) is installed on the third substrate (17) through the connecting mechanism.

7. The packaging structure of a silicon carbide device according to claim 6, characterized in that, The connecting mechanism includes a fixed bracket (21) fixedly connected to the third substrate (17), an adjusting screw (22) threadedly connected to the fixed bracket (21), a screw block (23) fixedly connected to one end of the adjusting screw (22), and the other end of the adjusting screw (22) passing through the fixed bracket (21) and rotatably connected to the second substrate (16), and the adjusting screw (22) is threadedly connected to the fixed bracket (21).

8. The packaging structure of a silicon carbide device according to claim 7, characterized in that, The connection mechanism also includes a storage tube (18) fixedly connected to the third substrate (17), the bottom surface of the storage tube (18) is slidably connected to an extension rod (19), and the bottom end of the extension rod (19) is fixedly connected to the second substrate (16).

9. The packaging structure of a silicon carbide device according to claim 6, characterized in that, A protective frame (20) is fixedly connected inside the first metal shell (1), and the protective frame (20) wraps around the outside of the three-layer structure formed by the first substrate (8), the silicon carbide chip structure (9) and the second substrate (16).

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