A metal clip welded automotive power module

Abstract

A metal Clip welded automotive power module. The metal Clip welded automotive power module includes a shell assembly, a chip assembly, and a heat dissipation column. The shell assembly includes a shell and a heat dissipation substrate. The chip assembly includes a ceramic copper clad laminate, a power chip, a bonding resistor, and a Clip connector. The Clip connector includes an extension portion, a welding portion, a notch, and a chip welding portion. The connection between the welding portion and the extension portion is stepped and the height of the welding portion is lower than the height of the extension portion. The chip welding portion is located on the end face of the extension portion facing the power chip. The chip welding portion is a rectangular protrusion extending in the direction of the power chip, and the edge of the chip welding portion is rounded. The Clip connector is provided to achieve the connection between the power chip and the ceramic copper clad laminate, thereby increasing the overcurrent capacity of the module and effectively improving the mechanical strength of the bond.

Description

Technical Field

[0001] The invention relates to the technical field of IGBT modules, and in particular to a metal Clip welded automotive power module. Background Art

[0002] A power module refers to a power electronic device that is packaged into a module according to a certain functional combination. At present, silicon carbide (SiC) power modules are increasingly used in the field of new energy vehicles. There are higher requirements for vehicle modules in terms of overcurrent capability and high reliability, which requires further improvement in the process and packaging of vehicle modules. The existing technology uses traditional wires to connect power circuits, but the reliability of the bonding wires used is insufficient. The bonding wires connecting the chips are often more likely to fall off. At the same time, the overcurrent capability of the bonding wires is weak and the heat dissipation capability is weak. Summary of the invention

[0003] In view of this, the present invention provides a metal Clip welded automotive power module to solve the above technical problems.

[0004] A metal Clip-welded automotive power module includes a housing component, a chip component disposed in the housing component, and a plurality of heat dissipation columns disposed on the housing component. The housing component includes a housing and a heat dissipation substrate disposed on the housing. The chip component includes a plurality of ceramic copper-clad boards disposed on the heat dissipation substrate, a plurality of power chips disposed on the ceramic copper-clad boards, a plurality of bonding resistors disposed on the ceramic copper-clad boards, and a plurality of Clip connectors disposed on the ceramic copper-clad boards. The Clip connector includes an extension, two welding parts disposed at both ends of the extension, a plurality of notches disposed on the extension, and a plurality of chip welding parts disposed on the extension. The connection between the welding part and the extension is in a step-like shape and the height of the welding part is lower than the height of the extension. The welding part is connected to the power circuit area of ​​the ceramic copper-clad board by welding, and the chip welding part is located on the end surface of the extension facing the power chip. The chip welding part is a rectangular protrusion extending in the direction of the power chip, and the edge of the chip welding part is rounded.

[0005] Furthermore, the housing assembly further comprises a cover plate disposed on the housing, and a plurality of power terminals disposed on the housing, a plurality of through holes are disposed at the center of the housing, and the cover plate covers the through holes. Furthermore, the through holes are filled with epoxy resin.

[0006] Furthermore, the power terminal is arranged on the inner side wall of the through hole and one end of the power terminal is connected to the chip assembly.

[0007] Furthermore, the heat dissipation substrate is a nickel-plated aluminum plate or a nickel-plated copper plate. The end surface of the heat dissipation substrate facing the housing is used to set the chip assembly, and the other end surface is used to set the heat dissipation column.

[0008] Furthermore, the chip assembly also includes a plurality of signal terminals arranged on the ceramic copper clad board.

[0009] Furthermore, the ceramic copper-clad laminate is a silicon nitride ceramic copper-clad laminate obtained by an active copper soldering process, and the ceramic copper-clad laminate is soldered to the heat dissipation substrate by a tin sheet process.

[0010] Furthermore, the power chip adopts a silicon carbide power chip that can be sintered with silver paste on both sides, and the bonding resistor and the power chip are respectively combined with different circuit areas on the front side of the ceramic copper clad board through a silver paste sintering process.

[0011] Furthermore, the length and width of the contact position between the chip welding portion and the power chip are 3.18mm*2.13mm.

[0012] Furthermore, the heat dissipation column array is arranged on the heat dissipation substrate, the heat dissipation columns are elliptical, and the two ends thereof that are far apart are diversion ends.

[0013] Compared with the prior art, the automotive power module with metal Clip welding provided by the present invention realizes the connection between the power chip and the ceramic copper-clad board by setting the Clip connector, thereby increasing the overcurrent capacity of the module and effectively improving the bonding mechanical strength. The chip welding part of the Clip connector is located on the end face of the extension part facing the power chip, and the chip welding part is a rectangular protrusion extending in the direction of the power chip. The edge of the chip welding part is rounded, so that it can contact the power chip alone for easy welding. At the same time, the rounded corners around it can be filled after welding, which can better weld with the power chip and avoid solder exceeding the chip area. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 A schematic structural diagram of a metal Clip-welded automotive power module provided by the present invention.

[0015] Figure 2 for Figure 1 Schematic diagram of the exploded structure of an automotive power module welded with metal clips.

[0016] Figure 3 for Figure 1 A top view of a metal clip-welded automotive power module with the cover removed.

[0017] Figure 4 for Figure 3An enlarged schematic diagram of the automotive power module A welded with metal clips.

[0018] Figure 5 for Figure 1 Schematic diagram of the structure of the Clip connector of the automotive power module welded with metal Clip.

[0019] Figure 6 for Figure 1 A schematic structural diagram of the housing assembly of a metal clip-welded automotive power module from another angle. DETAILED DESCRIPTION

[0020] The specific embodiments of the present invention are further described in detail below. It should be understood that the description of the embodiments of the present invention herein is not intended to limit the protection scope of the present invention.

[0021] like Figures 1 to 6 As shown, it is a schematic diagram of the structure of the metal Clip welded vehicle power module provided by the present invention. The metal Clip welded vehicle power module includes a housing component 10, a chip component 20 disposed in the housing component 10, and a plurality of heat dissipation columns 30 disposed on the housing component 10. It can be imagined that the metal Clip welded vehicle power module also includes some other functional modules, such as connection components, and installation components, etc., which are well known to those skilled in the art and will not be repeated here.

[0022] The housing assembly 10 includes a housing 11 , a heat dissipation substrate 12 disposed on the housing 11 , a cover plate 13 disposed on the housing 11 , and a plurality of power terminals 14 disposed on the housing 11 .

[0023] The housing 11 is used to carry the above-mentioned functional modules, so the housing 11 is provided with a variety of functional structures, such as screws, bolts, through holes, etc., to complete the installation and assembly of the above-mentioned functional modules, which can be provided according to actual needs and will not be described in detail one by one. The center of the housing 11 is provided with a plurality of through holes 111, and the through holes 111 are used to accommodate the chip assembly 20.

[0024] The heat dissipation substrate 12 is provided with a plurality of mounting holes 121, and the heat dissipation substrate 12 is fixed to the housing 11 by providing fasteners such as bolts in the mounting holes 121. The heat dissipation substrate 12 is a nickel-plated aluminum plate or a nickel-plated copper plate. The end surface of the heat dissipation substrate 12 facing the housing 11 is used to set the chip assembly 20, and the other end surface is used to set the heat dissipation column 30, so that the heat generated by the chip assembly 20 during operation is conducted to the heat dissipation column 30, and then the heat is dissipated through the heat dissipation column 30.

[0025] The cover plate 13 is disposed on the through hole 111 to seal the through hole 111 and protect the internal chip assembly 20 from dust. Before sealing, the through hole 111 may be filled with epoxy resin, which has the advantages of excellent thermal stability and high reliability temperature certification, thereby improving the heat resistance of the module, and its reliability temperature can reach above 200°C. The power terminal 14 is disposed on the inner side wall of the through hole 111 and one end is connected to the chip assembly 20.

[0026] The chip assembly 20 includes a plurality of ceramic copper clad laminates 21 arranged on the heat dissipation substrate 12, a plurality of power chips 22 arranged on the ceramic copper clad laminates 21, a plurality of bonding resistors 23 arranged on the ceramic copper clad laminates 21, a plurality of Clip connectors 24 arranged on the ceramic copper clad laminates 21, and a plurality of signal terminals 25 arranged on the ceramic copper clad laminates 21.

[0027] The ceramic copper clad board 21 is a silicon nitride ceramic copper clad board obtained by active copper soldering process (AMB). The ceramic copper clad board 21 is soldered to the heat dissipation substrate 12 by tin sheet process. The ceramic copper clad board 21 is mainly used as a carrier of various electronic components in power electronic module technology. Its surface has circuit areas for different electronic components, such as power circuit area and signal circuit area, etc., which should be the prior art and will not be repeated here.

[0028] In this embodiment, the power chip 22 is a silicon carbide power chip that can be sintered with double-sided silver paste. The bonding resistor 23 and the power chip 22 are respectively combined with different circuit areas on the front of the ceramic copper clad board 21 through a silver paste sintering process. The silver paste sintering process of this embodiment uses silver paste as a bonding material. The silver paste sintering temperature of the silver paste sintering process is 200°C-300°C, and the silver paste sintering pressure is 20Mpa-70Mpa. The bonding resistor 23 and the power chip 22 are electronic components, which should be prior art and will not be repeated here. A connecting wire is also required between the bonding resistor 23 and the power chip 22, one of which connects the bonding resistor 23 and the signal pole of the power chip 22, and the other connects the signal pole of the power chip 22 and the signal circuit area of ​​the ceramic copper clad board 21, which is used to achieve electrical connection, and aluminum wire is preferably used.

[0029] The Clip connector 24 includes an extension portion 241 , two soldering portions 242 respectively disposed at two ends of the extension portion 241 , a plurality of notches 243 disposed on the extension portion 241 , and a plurality of chip soldering portions 244 disposed on the extension portion 241 .

[0030] The extension portion 241 is in the shape of a straight plate, and the connection between the welding portion 242 and the extension portion 241 is in the shape of a step, and the height of the welding portion 242 is lower than the height of the extension portion 241, so that the extension portion 241 is supported by the welding portion 242, so that the extension portion 241 and the ceramic copper clad board 21 are spaced apart, leaving space for setting the chip welding portion 244 and the connecting wire. The welding portion 242 is connected to the power circuit area of ​​the ceramic copper clad board 21 by welding. The notch 243 will leak the bonding resistor 23 and part of the power chip 22, which is convenient for observation and welding, and at the same time plays a role of avoidance to avoid collapsing the connecting wire during welding to prevent affecting the bonding of the connecting wire.

[0031] The chip welding part 244 is located on the end face of the extension part 241 facing the power chip 22. The chip welding part 244 is formed by stamping. The chip welding part 244 is a rectangular protrusion extending in the direction of the power chip 22. The edge of the chip welding part 244 is rounded, so that it can contact the power chip 22 alone for welding. At the same time, the rounded corners around can be filled after welding, which can better weld with the power chip 22 and improve the connection strength. At the same time, it also plays a certain supporting role and improves the overall strength. Compared with copper wire, the use of Clip increases the overcurrent capacity of the module and effectively improves the mechanical strength of the bond. The length and width of the contact position between the chip welding part 244 and the power chip 22 are 3.18mm*2.13mm. In this embodiment, the Clip connector 24 is oxygen-free copper with high electrical conductivity and high thermal conductivity.

[0032] The signal terminal 25 is vertically disposed on the ceramic copper-clad board 21 , and one end of the signal terminal 25 extends out of the cover plate 13 .

[0033] The heat dissipation column 30 array is arranged on the heat dissipation substrate 12. When dissipating heat, coolant will flow through the heat dissipation column 30, thereby performing heat exchange and taking away heat. The heat dissipation method through the coolant should be the existing technology and will not be repeated. The heat dissipation column 30 is elliptical and its two ends with a long distance between them are shunt ends 31. The arrangement direction of the two shunt ends 31 is parallel to the flow direction of the coolant. Since the curvature of the shunt end 31 is smaller, the resistance encountered by the coolant when it flows is smaller, so that the coolant can flow faster, the flow resistance is smaller, which is more conducive to the heat dissipation of the module, so that the effective current of the module is higher, and the module can achieve higher power.

[0034] Compared with the prior art, the automotive power module with metal Clip welding provided by the present invention realizes the connection between the power chip 22 and the ceramic copper-clad board 21 by setting the Clip connector 24, thereby increasing the overcurrent capacity of the module and effectively improving the mechanical strength of the bonding. The chip welding portion 244 of the Clip connector 24 is located on the end face of the extension portion 241 facing the power chip 22. The chip welding portion 244 is a rectangular protrusion extending in the direction of the power chip 22. The edge of the chip welding portion 244 is rounded, so that it can contact the power chip 22 alone for easy welding. At the same time, the rounded corners around it can be filled after welding, which can better weld with the power chip 22 and avoid solder exceeding the chip area.

[0035] The above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modification, equivalent substitution or improvement within the spirit of the present invention is included in the scope of the claims of the present invention.

Claims

1. A metal clip welded automotive power module, characterized in that: The automotive power module welded with the metal Clip includes a shell component, a chip component arranged in the shell component, and a plurality of heat dissipation columns arranged on the shell component. The shell component includes a shell and a heat dissipation substrate arranged on the shell. The chip component includes a plurality of ceramic copper-clad laminates arranged on the heat dissipation substrate, a plurality of power chips arranged on the ceramic copper-clad laminate, a plurality of bonding resistors arranged on the ceramic copper-clad laminate, and a plurality of Clip connectors arranged on the ceramic copper-clad laminate. The Clip connector includes an extension portion, two welding portions respectively arranged at both ends of the extension portion, a plurality of notches arranged on the extension portion, and a plurality of chip welding portions arranged on the extension portion. The connection between the welding portion and the extension portion is stepped and the height of the welding portion is lower than the height of the extension portion. The welding portion is connected to the power circuit area of ​​the ceramic copper-clad laminate by welding. The chip welding portion is located on the end surface of the extension portion facing the power chip. The chip welding portion is a rectangular protrusion extending in the direction of the power chip, and the edge of the chip welding portion is rounded.

2. The metal clip welded automotive power module according to claim 1, characterized in that: The housing assembly further comprises a cover plate arranged on the housing, and a plurality of power terminals arranged on the housing. A plurality of through holes are arranged at the center of the housing, and the cover plate is arranged to cover the through holes.

3. The metal clip welded automotive power module according to claim 2, characterized in that: The through hole is filled with epoxy resin.

4. The metal clip welded automotive power module according to claim 2, characterized in that: The power terminal is arranged on the inner side wall of the through hole and one end of the power terminal is connected to the chip component.

5. The metal clip welded automotive power module according to claim 1, characterized in that: The heat dissipation substrate is a nickel-plated aluminum plate or a nickel-plated copper plate. The end surface of the heat dissipation substrate facing the shell is used to set the chip component, and the other end surface is used to set the heat dissipation column.

6. The automotive power module welded by metal clip according to claim 1, characterized in that: The chip assembly also includes a plurality of signal terminals arranged on the ceramic copper clad board.

7. The metal clip welded automotive power module according to claim 1, characterized in that: The ceramic copper-clad board is a silicon nitride ceramic copper-clad board obtained by an active copper soldering process, and the ceramic copper-clad board is soldered to the heat dissipation substrate by a tin sheet process.

8. The metal clip welded automotive power module according to claim 1, characterized in that: The power chip adopts a silicon carbide power chip that can be sintered with double-sided silver paste. The bonding resistor and the power chip are respectively combined with different circuit areas on the front side of the ceramic copper clad board through a silver paste sintering process.

9. The metal clip welded automotive power module according to claim 1, characterized in that: The length and width of the contact position between the chip welding portion and the power chip are 3.18 mm*2.13 mm.

10. The metal clip welded automotive power module according to claim 1, characterized in that: The heat dissipation column array is arranged on the heat dissipation substrate. The heat dissipation columns are elliptical in shape, and two ends of the columns that are far apart are diversion ends.

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