Anti-warping vacuum platform and power module

Abstract

The application relates to a warping-preventing vacuum platform and a power module. The warping-preventing vacuum platform is used for a ceramic copper-clad substrate and comprises a platform body, the platform body comprises opposite first and second surfaces and a side surface connecting the first and second surfaces, the first surface is provided with a plurality of vacuum suction holes, a vacuum pipeline in communication with the vacuum suction holes is arranged in the platform body, an external connecting hole in communication with the vacuum pipeline is arranged on the side surface, the first surface is a curved surface and is arranged to protrude away from the second surface. The warping-preventing vacuum platform improves the warping problem, facilitates bonding between the ceramic copper-clad substrate and chips in subsequent processes, avoids excessive deformation of the ceramic copper-clad substrate under the suction of the vacuum suction holes, influences the structural strength of the ceramic copper-clad substrate, and ensures the reliability of the ceramic copper-clad substrate.

Description

Technical Field

[0001] This application relates to the field of power module technology, and in particular to an anti-warping vacuum platform and a power module. Background Technology

[0002] Power modules typically consist of a copper-clad ceramic substrate. Copper-clad ceramic substrates possess excellent thermal cycling properties, shape stability, high rigidity, high thermal conductivity, and high reliability. Various patterns can be etched onto the copper-clad surface. Furthermore, it is a pollution-free and environmentally friendly product with a wide operating temperature range of -55℃ to 850℃. Its coefficient of thermal expansion is close to that of silicon, making it suitable for a wide range of applications: semiconductor coolers, electronic heaters, high-power semiconductor modules, power control circuits, hybrid power circuits, intelligent power components, high-frequency switching power supplies, solid-state relays, automotive electronics, aerospace and military electronic components, solar panel components, telecommunications switches, receiving systems, and laser industrial electronics.

[0003] However, existing copper-clad ceramic substrates have warping issues, which affect the bonding between the copper-clad ceramic substrate and components such as chips. Utility Model Content

[0004] This application provides an anti-warping vacuum platform and a power module, including a platform body. Vacuum adsorption holes are provided on the first surface of the platform body to adsorb warped ceramic copper-clad substrates, causing deformation of the warped substrates, reducing the degree of warping, and flattening them as much as possible. When the ceramic copper-clad substrate is fixed on the anti-warping vacuum platform, it protrudes and warps away from the platform body. Therefore, the suction force generated by the vacuum adsorption holes can pull this protruding part towards the platform body, making the ceramic copper-clad substrate and the first surface of the platform body fit together, thereby improving the warping problem and facilitating subsequent bonding processes between the ceramic copper-clad substrate and the chip. Furthermore, in this application, the first surface is curved and protrudes away from the second surface to avoid excessive deformation of the ceramic copper-clad substrate under the adsorption of the vacuum adsorption holes, which would affect the structural strength of the ceramic copper-clad substrate and ensure its reliability.

[0005] On one hand, this application provides an anti-warping vacuum platform for a ceramic copper-clad substrate, comprising: a platform body, the platform body including a first surface, a second surface and a side surface connecting the first surface and the second surface, the first surface having a plurality of vacuum adsorption holes, a vacuum pipeline communicating with the vacuum adsorption holes in the platform body, and an external connection hole communicating with the vacuum pipeline in the side surface, the first surface being curved and protruding in a direction away from the second surface.

[0006] According to one aspect of the embodiments of this application, the first surface includes a first long side and a first short side connected to the first long side, the first long side extends along a first direction, and the first short side extends along a second direction; along the first direction, the distance between the first surface and the second surface decreases from the center of the first surface to the edge of the first surface.

[0007] According to one aspect of the embodiments of this application, along the first direction, the first surface includes a central region and edge regions respectively disposed on both sides of the central region, the distance between the first surface and the second surface located in the central region is a first distance, and the distance between the first surface and the second surface located in the edge regions is a second distance; the difference between the first distance and the second distance is greater than or equal to 0.05 mm and less than or equal to 0.35 mm.

[0008] According to one aspect of the embodiments of this application, the vacuum adsorption holes are arranged at intervals along the first direction and the second direction, respectively.

[0009] According to one aspect of the embodiments of this application, the distance between two adjacent vacuum adsorption holes along the first direction is greater than or equal to the distance between two adjacent vacuum adsorption holes along the second direction.

[0010] According to one aspect of the embodiments of this application, the vacuum adsorption hole includes a circular hole, and the diameter of the vacuum adsorption hole is greater than or equal to 4 mm and less than or equal to 6 mm.

[0011] According to one aspect of the embodiments of this application, a protective layer covering the platform body is further included, the thickness of the protective layer being greater than or equal to 0.5 mm.

[0012] According to one aspect of the present application, the vacuum pipeline includes a first pipe extending along the first direction; the vacuum adsorption hole includes a group of vacuum adsorption holes spaced apart along the first direction, and the group of vacuum adsorption holes includes at least two vacuum adsorption holes spaced apart along the second direction; the orthographic projection of the first pipe on the first surface covers one group of vacuum adsorption holes, and the first pipe and the vacuum adsorption holes in the corresponding covered group of vacuum adsorption holes are connected.

[0013] According to one aspect of the present application, the vacuum pipeline further includes a second pipe extending in a second direction; the vacuum adsorption hole in the vacuum adsorption hole group is connected to at least one of the first pipe and one of the second pipe.

[0014] On the other hand, embodiments of this application also provide a power module, including: a warped ceramic copper-clad substrate to be bonded, wherein the ceramic copper-clad substrate is fixed and bonded on the anti-warping vacuum platform described in any of the above embodiments.

[0015] Compared to existing technologies, the anti-warping vacuum platform provided in this application includes a platform body and a vacuum adsorption hole on the first surface of the platform body to adsorb the warped ceramic copper-clad substrate, causing the warped ceramic copper-clad substrate to deform, reducing the degree of warping, and flattening it as much as possible. When the ceramic copper-clad substrate is fixed on the anti-warping vacuum platform, it protrudes and warps away from the platform body. Therefore, the suction force generated by the vacuum adsorption hole can pull this protruding part towards the platform body, so that the ceramic copper-clad substrate and the first surface of the platform body are in contact, thereby improving the warping problem and facilitating subsequent bonding processes between the ceramic copper-clad substrate and the chip. At the same time, in this application, the first surface is curved and protrudes away from the second surface to avoid excessive deformation of the ceramic copper-clad substrate under the adsorption of the vacuum adsorption hole, which would affect the structural strength of the ceramic copper-clad substrate and ensure the reliability of the ceramic copper-clad substrate. Attached Figure Description

[0016] The features, advantages, and technical effects of exemplary embodiments of this application will now be described with reference to the accompanying drawings.

[0017] Figure 1 This is a schematic diagram of the anti-warping vacuum platform provided in one embodiment of the present invention; Figure 2 This is one embodiment of the present utility model. Figure 1 Sectional view at point AA; Figure 3 This is one embodiment of the present utility model. Figure 1 Sectional view at point BB; Figure 4 This is a schematic diagram of the anti-warping vacuum platform and the ceramic copper-clad substrate provided in another embodiment of the present invention.

[0018] Figure label: 100. Platform body; 11. Vacuum adsorption hole; 12. Vacuum pipeline; 121. First pipeline; 122. Second pipeline; B1, First long side; B2, First short side; F1, First surface; F2, Second surface; C, Side surface; K1, External hole; 200, Ceramic copper-clad substrate; A1, Central area; A2, Edge area; X, First direction; Y, Second direction.

[0019] In the accompanying drawings, the same parts use the same reference numerals. The drawings are not drawn to scale. Detailed Implementation

[0020] The features and exemplary embodiments of various aspects of this application will now be described in detail. Numerous specific details are set forth in the following detailed description to provide a comprehensive understanding of this application. However, it will be apparent to those skilled in the art that this application can be implemented without requiring some of these specific details. The following description of embodiments is merely intended to provide a better understanding of this application by illustrating examples. In the accompanying drawings and the following description, at least some well-known structures and techniques are not shown to avoid unnecessarily obscuring the application; and, for clarity, the dimensions of some structures may be exaggerated. Furthermore, the features, structures, or characteristics described below can be combined in any suitable manner in one or more embodiments.

[0021] The directional terms used in the following description refer to the directions shown in the figures and are not intended to limit the specific structure of the anti-warping vacuum platform of this application. It should also be noted in the description of this application that, unless otherwise explicitly specified and limited, the terms "installation" and "connection" 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 direct connection or an indirect connection. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0022] To better understand this application, the following will be combined with... Figures 1 to 4 The anti-warping vacuum platform and power module of the present application embodiment are described in detail.

[0023] Please see Figures 1 to 3 , Figure 1 This is a schematic diagram of the anti-warping vacuum platform provided in one embodiment of the present invention; Figure 2 This is one embodiment of the present utility model. Figure 1 Sectional view at point AA; Figure 3 This is one embodiment of the present utility model. Figure 1 Sectional view at point BB.

[0024] This application provides an anti-warping vacuum platform for a ceramic copper-clad substrate 200, comprising: a platform body 100, the platform body 100 including a first surface F1, a second surface F2, and a side surface C connecting the first surface F1 and the second surface F2; the first surface F1 is provided with a plurality of vacuum adsorption holes 11; a vacuum pipeline 12 communicating with the vacuum adsorption holes 11 is provided in the platform body 100; and an external connection hole K1 communicating with the vacuum pipeline 12 is provided on the side surface C; the first surface F1 is curved and protrudes in a direction away from the second surface F2.

[0025] The anti-warping vacuum platform provided in this embodiment includes a platform body 100, and a vacuum adsorption hole 11 is provided on the first surface F1 of the platform body 100 to adsorb the warped ceramic copper-clad substrate 200, thereby deforming the warped ceramic copper-clad substrate 200, reducing the degree of warping, and flattening it as much as possible. When the ceramic copper-clad substrate 200 is fixed on the anti-warping vacuum platform, the ceramic copper-clad substrate 200 protrudes and warps away from the platform body 100. Therefore, the suction force generated by the vacuum adsorption hole 11 can remove this protruding part. The ceramic copper-clad substrate 200 is lifted and attracted to the platform body 100, so that the first surface F1 of the ceramic copper-clad substrate 200 and the platform body 100 are in contact, thereby improving the lifting problem and facilitating subsequent bonding processes between the ceramic copper-clad substrate 200 and the chip. At the same time, in this application, the first surface F1 is curved and protrudes away from the second surface F2 to avoid excessive deformation of the ceramic copper-clad substrate 200 under the adsorption of the vacuum adsorption hole 11, which would affect the structural strength of the ceramic copper-clad substrate 200 and ensure the reliability of the ceramic copper-clad substrate 200.

[0026] In this embodiment, the vacuum line 12 can be connected to an external vacuum device through the external connection hole K1 to generate negative pressure suction, so that the vacuum adsorption hole 11 connected to the vacuum line 12 can effectively adsorb and drive the ceramic copper-clad substrate 200 to deform, thereby improving warping.

[0027] Optionally, the external connector K1 can be connected to an external pipeline connector.

[0028] Please see Figure 4 The ceramic copper-clad substrate 200 can be used in devices such as power modules. The existing ceramic copper-clad substrate 200 has a warpage of about 1.2mm, that is, the distance between the lower surface of the warped part of the ceramic copper-clad substrate 200 and the first surface F1 is about 1.2mm, such as 1.16mm.

[0029] Ceramic copper-clad substrate 200 is an electronic base material in which copper foil is sintered onto a ceramic surface using DCB (direct copper bonding) or AMB (active metal brazing) technology. It is primarily used in high-power semiconductor modules, new energy vehicles, photovoltaics, and aerospace. This material uses high thermal conductivity ceramics such as alumina and aluminum nitride as the matrix, exhibiting characteristics such as thermal conductivity of 20-260 W / mK and insulation voltage >20 kV / mm, with an applicable temperature range covering -55℃ to 850℃.

[0030] Please see Figures 3 to 4In some optional embodiments, the orthographic projection of the first surface F1 onto the second surface F2 is a rectangle or a rounded rectangle, or other polygon. The first surface F1 includes a first long side B1 and a first short side B2 connected to the first long side B1. The first long side B1 extends along a first direction X, and the first short side B2 extends along a second direction Y. Along the first direction X, the distance between the first surface F1 and the second surface F2 decreases from the center of the first surface F1 to the edge of the first surface F1.

[0031] In this embodiment, the rounded rectangle, i.e., the curved shape with chamfered corners, can avoid bumps and knocks. Along the first direction X, the distance between the first surface F1 and the second surface F2 decreases from the center of the first surface F1 to the edge of the first surface F1. That is, along the first direction X, the first surface F1 has a structure that is thicker in the middle and thinner at both sides. The middle of the first surface F1 protrudes more in the direction away from the second surface F2 to correspond to the middle part of the ceramic copper-clad substrate 200 with the greatest warpage, so as to avoid excessive deformation of the ceramic copper-clad substrate 200.

[0032] Of course, the protrusion distance at the center of the first surface F1 needs to be much smaller than the warpage of the ceramic copper-clad substrate 200, otherwise it will affect the warpage improvement effect.

[0033] Optionally, the distance between the highest and lowest points on the first surface F1 is less than or equal to 0.35 mm. However, the distance between the lower surface of the warped portion of the corresponding ceramic copper-clad substrate 200 and the first surface F1 is 1.2 mm, which is much greater than 0.35 mm.

[0034] In some optional embodiments, along the first direction X, the first surface F1 includes a central region A1 and edge regions A2 respectively disposed on both sides of the central region A1. The distance between the first surface F1 and the second surface F2 located in the central region A1 is a first distance, and the distance between the first surface F1 and the second surface F2 located in the edge region A2 is a second distance. The difference between the first distance and the second distance is greater than or equal to 0.05 mm and less than or equal to 0.35 mm.

[0035] In this embodiment, since the distance between the first surface F1 and the second surface F2 decreases from the center of the first surface F1 to the edge of the first surface F1 along the first direction X, the closer the first surface F1 located in the edge region A2 is to the center region A1, the greater its thickness, i.e., the greater the corresponding second distance. The farther the first surface F1 located in the edge region A2 is from the center region A1, the smaller its thickness, i.e., the smaller the corresponding second distance. Therefore, the difference between the first distance and the second distance is not a fixed value and can be set according to the actual position and requirements.

[0036] Optionally, the difference between the first distance and the second distance can be equal to any one of 0.05mm, 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, or 0.35mm.

[0037] In some optional embodiments, the vacuum adsorption holes 11 are arranged at intervals along the first direction X and the second direction Y to adsorb at different positions of the ceramic copper-clad substrate 200 and improve warpage. For example, the vacuum adsorption holes 11 can be arranged uniformly at intervals along the first direction X and the second direction Y, or they can be arranged non-uniformly according to actual needs. For example, considering that the ceramic copper-clad substrate 200 corresponding to the central region A1 has greater warpage, the number of vacuum adsorption holes 11 on the first surface F1 of the central region A1 can be greater than the number of vacuum adsorption holes 11 on the first surface F1 of the edge region A2 to increase the adsorption force of the central region A1, so that the ceramic copper-clad substrate 200 corresponding to the central region A1 can generate sufficient deformation.

[0038] Alternatively, the density of vacuum adsorption holes 11 on the first surface F1 of the central region A1 can be greater than the density of vacuum adsorption holes 11 on the first surface F1 of the edge region A2.

[0039] In some optional embodiments, the distance between two adjacent vacuum adsorption holes 11 along the first direction X is greater than or equal to the distance between two adjacent vacuum adsorption holes 11 along the second direction Y. This increases the density of the vacuum adsorption holes 11 in the second direction Y, ensuring adsorption force.

[0040] In some optional embodiments, the vacuum adsorption hole 11 includes a circular hole, and the diameter of the vacuum adsorption hole 11 is greater than or equal to 4 mm and less than or equal to 6 mm.

[0041] In this embodiment, the vacuum adsorption hole 11 can be in the form of a circular hole, which is convenient for preparation. The diameter of the vacuum adsorption hole 11 should not be too large, as this may generate excessive adsorption force, causing damage to the ceramic copper-clad substrate 200. Conversely, the diameter of the vacuum adsorption hole 11 should not be too small, as this will result in insufficient adsorption force and poor improvement of the warpage of the ceramic copper-clad substrate 200. Optionally, the diameter of the vacuum adsorption hole 11 can be any one of 4mm, 4.5mm, 5mm, 5.5mm, or 6mm.

[0042] In some optional embodiments, the anti-warping vacuum platform also includes a protective layer covering the platform body 100, the thickness of which is greater than or equal to 0.5 mm.

[0043] Understandably, the platform body 100 can be made of metal or other hard materials to improve its service life. To prevent collisions and scratches between the platform body 100 and the ceramic copper-clad substrate 200, a relatively soft protective layer can be provided. For example, the protective layer can be made of materials such as rubber or silicone. For instance, the protective layer can be made of black silicone. The thickness of the protective layer should not be too small, otherwise it will not be able to provide cushioning and protection. For example, the thickness of the protective layer can be any of 0.5mm, 0.6mm, 0.7mm, or 0.8mm.

[0044] Please see Figure 1 In some optional embodiments, the vacuum conduit 12 includes a first conduit 121 extending along a first direction X; the vacuum adsorption holes 11 include a group of vacuum adsorption holes 11 spaced apart along the first direction X, and the group of vacuum adsorption holes 11 includes at least two vacuum adsorption holes 11 spaced apart along a second direction Y; the orthographic projection of the first conduit 121 on the first surface F1 covers a group of vacuum adsorption holes 11, and the first conduit 121 is connected to the vacuum adsorption holes 11 in the corresponding covered group of vacuum adsorption holes 11.

[0045] In this embodiment, in order to simplify the structure, a first pipe 121 can be used to connect to multiple vacuum adsorption holes 11 in a group of vacuum adsorption holes 11 at the same time, and provide negative pressure suction to multiple vacuum adsorption holes 11.

[0046] Optionally, the vacuum line 12 also includes a second pipe 122 extending along the second direction Y; the vacuum adsorption holes 11 in the group of vacuum adsorption holes 11 are connected to at least one first pipe 121 and one second pipe 122.

[0047] It is understandable that, considering that the negative pressure suction generated by the first pipe 121 extending along the first direction X may not be able to make the warped ceramic copper-clad substrate 200 and the first surface F1 fit together, a second pipe 122 extending along the second direction Y and connected to the vacuum adsorption hole 11 can be additionally provided to ensure negative pressure suction.

[0048] This application also provides a power module, including: a warped ceramic copper-clad substrate 200 to be bonded, wherein the ceramic copper-clad substrate 200 is fixed and bonded on an anti-warping vacuum platform in any of the above embodiments.

[0049] In this embodiment, the ceramic copper-clad substrate 200 needs to be bonded to components such as chips. It is necessary to first use an anti-warping vacuum platform to improve the warping problem of the ceramic copper-clad substrate 200. The active warping compensation and the anti-warping vacuum platform are in conformal contact. The warping improvement function of the anti-warping vacuum platform is deeply integrated with the subsequent bonding process to achieve multi-variable closed-loop control.

[0050] In the power module provided in this application embodiment, the warped ceramic copper-clad substrate 200 to be bonded can be placed on the platform body 100 of the anti-warping vacuum platform. The first surface F1 of the platform body 100 is provided with vacuum adsorption holes 11 to adsorb the warped ceramic copper-clad substrate 200, causing it to deform, reducing the degree of warping, and flattening it as much as possible. When the ceramic copper-clad substrate 200 is fixed on the anti-warping vacuum platform, it protrudes and warps away from the platform body 100. Therefore, the vacuum... The suction force generated by the vacuum adsorption hole 11 can pull this protruding part towards the platform body 100, so that the ceramic copper-clad substrate 200 and the first surface F1 of the platform body 100 are in contact, thereby improving the lifting problem and facilitating subsequent bonding processes between the ceramic copper-clad substrate 200 and the chip. At the same time, in this application, the first surface F1 is curved and protrudes away from the second surface F2 to avoid excessive deformation of the ceramic copper-clad substrate 200 under the adsorption of the vacuum adsorption hole 11, which would affect the structural strength of the ceramic copper-clad substrate 200 and ensure the reliability of the ceramic copper-clad substrate 200.

[0051] Although this application has been described with reference to preferred embodiments, various modifications can be made thereto and components can be replaced with equivalents without departing from the scope of this application. In particular, the technical features mentioned in the various embodiments can be combined in any manner, provided there is no structural conflict. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. An anti-warping vacuum platform for use on copper-clad ceramic substrates, characterized in that, include: The platform body includes a first surface, a second surface, and a side surface connecting the first surface and the second surface. The first surface is provided with a plurality of vacuum adsorption holes. A vacuum pipeline communicating with the vacuum adsorption holes is provided in the platform body. An external connection hole communicating with the vacuum pipeline is provided on the side surface. The first surface is curved and protrudes in a direction away from the second surface.

2. The anti-warping vacuum platform according to claim 1, characterized in that, The first surface includes a first long side and a first short side connected to the first long side, the first long side extending along a first direction and the first short side extending along a second direction; Along the first direction, the distance between the first surface and the second surface decreases from the center of the first surface to the edge of the first surface.

3. The anti-warping vacuum platform according to claim 2, characterized in that, Along the first direction, the first surface includes a central region and edge regions respectively disposed on both sides of the central region. The distance between the first surface and the second surface located in the central region is a first distance, and the distance between the first surface and the second surface located in the edge regions is a second distance. The difference between the first distance and the second distance is greater than or equal to 0.05 mm and less than or equal to 0.35 mm.

4. The anti-warping vacuum platform according to claim 2, characterized in that, The vacuum adsorption pores are arranged at intervals along the first direction and the second direction, respectively.

5. The anti-warping vacuum platform according to claim 2, characterized in that, The distance between two adjacent vacuum adsorption holes along the first direction is greater than or equal to the distance between two adjacent vacuum adsorption holes along the second direction.

6. The anti-warping vacuum platform according to claim 2, characterized in that, The vacuum adsorption hole includes a circular hole, and the diameter of the vacuum adsorption hole is greater than or equal to 4 mm and less than or equal to 6 mm.

7. The anti-warping vacuum platform according to claim 2, characterized in that, It also includes a protective layer covering the platform body, the thickness of which is greater than or equal to 0.5 mm.

8. The anti-warping vacuum platform according to claim 2, characterized in that, The vacuum line includes a first conduit extending along the first direction; The vacuum adsorption pores include a group of vacuum adsorption pores spaced apart along the first direction, and the group of vacuum adsorption pores includes at least two vacuum adsorption pores spaced apart along the second direction. The orthographic projection of the first pipe onto the first surface covers one of the vacuum adsorption hole groups, and the first pipe is connected to the vacuum adsorption holes in the corresponding covered vacuum adsorption hole group.

9. The anti-warping vacuum platform according to claim 8, characterized in that, The vacuum line also includes a second pipe extending in the second direction; The vacuum adsorption pore group is connected to at least one of the first pipes and one of the second pipes.

10. A power module, characterized in that, include: A warped ceramic copper-clad substrate to be bonded, the ceramic copper-clad substrate being fixed and bonded on an anti-warping vacuum platform as described in any one of claims 1 to 9.

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