Substrate assembly with metal heat sink, and method for manufacturing metal heat sink

Abstract

Disclosed in the present invention are a substrate assembly with a metal heat sink, and a method for manufacturing a metal heat sink. The substrate assembly comprises: a ceramic substrate, comprising a ceramic core plate, and a first copper foil layer and a second copper foil layer, which are respectively arranged on two opposite surface sides of the ceramic core plate; a circuit board, wherein an electrically conductive member connected to the first copper foil layer is provided in an insulating substrate of the circuit board, a surface circuit is provided on the side surface of the insulating substrate facing away from the ceramic substrate, and the surface circuit comprises a pad arranged on the electrically conductive member; and a metal heat sink, comprising a heat dissipation plate and a plurality of heat dissipation columns, wherein the heat dissipation plate is connected to the second copper foil layer, and the heat dissipation columns are connected to the heat dissipation plate by means of sintering or welding. The method for manufacturing a metal heat sink comprises: printing a sintering or welding material on a surface of a heat dissipation plate; and inserting heat dissipation columns into positioning holes of a fixture plate, and fixing the fixture plate to the heat dissipation plate, such that the heat dissipation columns come into close contact with the sintering or welding material, thereby achieving the accurate and reliable sintering of the heat dissipation columns. The present invention has the advantage of good heat dissipation performance.

Description

Carrier plate assembly with metal heat sink and manufacturing method of metal heat sink Technical Field

[0001] This invention relates to a carrier assembly for semiconductor device packaging; more specifically, it relates to a carrier assembly with a metal heat sink and a method for manufacturing the metal heat sink. Background Technology

[0002] Power semiconductor devices such as IGBTs (Insulated Gate Bipolar Transistors) and / or MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors) typically require large operating currents and generate a lot of heat during operation, thus requiring their packaging substrates to have high current carrying capacity and heat dissipation performance.

[0003] To improve heat dissipation, a heat sink is typically attached to the carrier plate. Traditional heat sinks usually consist of multiple fins. Heat generated by power semiconductor devices is conducted from the carrier plate to the heat sink and then dissipated through the fins, achieving cooling. However, these finned heat sinks are generally formed by die casting or machining of metal blocks, resulting in significant weight and volume, as well as high material costs. Summary of the Invention

[0004] In order to at least partially solve the problems of the prior art, the main objective of the present invention is to provide a carrier plate assembly with a metal heat sink that is conducive to lightweighting and reducing its cost.

[0005] Another object of the present invention is to provide a method for manufacturing a metal radiator.

[0006] To achieve the aforementioned main objective, a first aspect of the present invention provides a carrier plate assembly with a metal heat sink, comprising:

[0007] A ceramic substrate includes a ceramic core plate and a first copper foil layer and a second copper foil layer respectively disposed on two opposite surfaces of the ceramic core plate.

[0008] A circuit board is disposed on the first surface side of the ceramic substrate; wherein, the circuit board has a conductive element connected to the first copper foil layer within its insulation, and the insulating substrate has surface lines on the side surface facing away from the ceramic substrate, the surface lines including pads disposed on the conductive element.

[0009] A metal heat sink is disposed on the second surface side of the ceramic substrate; the metal heat sink includes a heat sink plate and a plurality of heat sink columns, the heat sink plate is connected to the second copper foil layer of the ceramic substrate, and the heat sink columns are sintered or welded to the heat sink plate.

[0010] The above technical solution has the following beneficial effects:

[0011] (1) Compared with traditional die-cast or machined metal radiators, the metal radiator of the present invention adopts a sintered or welded connection structure between the heat dissipation column and the heat dissipation plate, which is beneficial to reduce the material cost and weight of the metal radiator, thereby promoting the lightweighting of the carrier plate assembly and reducing the manufacturing cost of the carrier plate assembly.

[0012] (2) The insulating substrate of the circuit board is provided with conductive components. The conductive components can not only transmit the large current required by the power semiconductor device, but also, since the conductive components are connected to the pads and the first copper foil layer (i.e., penetrate the insulating substrate), heat can be quickly conducted to the ceramic substrate and the metal heat sink through the conductive components to achieve rapid heat dissipation.

[0013] (3) The carrier board assembly includes a ceramic substrate disposed between the circuit board and the metal heat sink. Electrical insulation is achieved using a ceramic core plate with excellent electrical insulation properties within the ceramic substrate, which improves the voltage withstand performance of the carrier board assembly. The first copper foil layer of the ceramic substrate is connected to the conductive components, allowing both to carry large currents together, further enhancing the current-carrying capacity of the carrier board assembly.

[0014] Furthermore, the heat dissipation column includes a column body and a connecting seat, the connecting seat having a connecting surface that is sintered or welded to the heat dissipation plate; wherein, the surface area of ​​the connecting surface is larger than the cross-section of the column body, so as to increase the connection strength between the heat dissipation column and the heat dissipation plate.

[0015] Furthermore, the thickness of the sintered or welded material between the heat sink and the heat sink column is 0.01mm to 0.05mm.

[0016] Furthermore, the heat dissipation column is a copper column, and the heat dissipation plate is a copper plate; preferably, the thickness of the copper plate is 1mm to 5mm.

[0017] Furthermore, the heat sink is sintered or welded to the second copper foil layer; preferably, the thickness of the sintering or welding material between the heat sink and the second copper foil layer is 0.05mm to 0.1mm.

[0018] Furthermore, the number of conductive elements is multiple, and the first copper foil layer is provided with multiple mutually spaced conductive portions, and the multiple conductive elements are respectively connected to the multiple conductive portions.

[0019] Furthermore, the conductive component is provided with a boss, and the solder pad is disposed on the boss. Providing a boss on the conductive component increases the wiring area on the surface of the insulating substrate, which is beneficial for the miniaturization of the circuit board and carrier board assembly.

[0020] Furthermore, the conductive element is a copper conductive element, and the copper conductive element is sintered or welded to the first copper foil layer; preferably, the thickness of the sintering or welding material between the conductive element and the first copper foil layer is 0.05mm to 0.1mm.

[0021] Furthermore, the materials used for the aforementioned sintering or welding can be, for example, metal pastes such as copper paste or silver paste, with copper paste being preferred.

[0022] To achieve the aforementioned objective, a second aspect of the present invention discloses a method for manufacturing a metal radiator, the metal radiator comprising a heat sink and a plurality of heat sink columns disposed on the heat sink; wherein the manufacturing method comprises the following steps:

[0023] S100, printing sintered or welded material on the surface of the heat sink;

[0024] S200, insert the plurality of heat dissipation columns into the positioning holes of the fixture plate, and fix the fixture plate to the heat dissipation plate so that the heat dissipation columns are in close contact with the sintering or welding material;

[0025] S300, sintering or welding is performed to connect the heat sink to the heat sink plate;

[0026] S400, Remove the fixture plate to complete the fabrication of the metal radiator.

[0027] Furthermore, the size of the positioning hole in the fixture plate is smaller than that of the connecting seat of the heat dissipation column.

[0028] In the above technical solution, the heat dissipation column of the metal radiator is sintered or welded to the heat dissipation plate, which helps to reduce the material cost and weight of the radiator. The fixture plate for positioning the heat dissipation column is fixed to the heat dissipation plate. During the sintering or welding connection, the fixture plate is used to position the heat dissipation column and apply pressure, so that the heat dissipation column is in close contact with the sintering or welding material. This not only helps to achieve a precise and reliable connection of the heat dissipation column on the heat dissipation plate, but also allows for the simultaneous sintering or welding connection of multiple heat dissipation columns, thereby improving the production efficiency of the metal radiator / carrier plate assembly.

[0029] To more clearly illustrate the purpose, technical solution, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0030] Figure 1 is a schematic diagram of the overall structure of the carrier plate assembly from a first-view perspective in the embodiment;

[0031] Figure 2 is a schematic diagram of the overall structure of the carrier plate assembly from a second perspective in the embodiment;

[0032] Figure 3 is a first-view exploded structural diagram of the carrier plate assembly in the embodiment;

[0033] Figure 4 is a second-view exploded structural diagram of the carrier plate assembly in the embodiment;

[0034] Figure 5 is a cross-sectional view of the carrier assembly (with the metal heat sink removed) in the embodiment;

[0035] Figure 6 is a schematic diagram of the heat dissipation column in the embodiment;

[0036] Figure 7 is a cross-sectional structural diagram of the heat dissipation column positioned by the jig plate in the embodiment;

[0037] Figure 8 is a three-dimensional structural diagram of the heat dissipation column positioned using a jig plate in the embodiment. Detailed Implementation

[0038] Numerous specific details are set forth in the following description to provide a thorough understanding of the invention; however, the invention may also be practiced in other ways different from those described herein. Therefore, the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0039] As shown in Figures 1 to 5, a first aspect of the present invention discloses a carrier assembly, including a ceramic substrate 10, a circuit board 20, and a metal heat sink 30. The circuit board 20 is disposed on a first surface side of the ceramic substrate 10, and the metal heat sink 30 is disposed on a second surface side of the ceramic substrate 10.

[0040] The ceramic substrate 10 includes a ceramic core plate 11, a first copper foil layer 12, and a second copper foil layer 13. The first copper foil layer 12 and the second copper foil layer 13 are located on the first surface and the second surface of the ceramic substrate 10, respectively. The ceramic core plate 11 is disposed between the first copper foil layer 12 and the second copper foil layer 13. Specifically, the ceramic core plate 11 can be aluminum nitride, silicon nitride, or alumina ceramic. The thickness of the ceramic core plate 11 can be 0.3 mm. The thickness of the first copper foil layer 12 and the second copper foil layer 13 can be the same, both being 0.35 mm. However, the present invention is not limited to this. For example, the thicknesses of the first copper foil layer 12 and the second copper foil layer 13 can be different.

[0041] The circuit board 20 includes, for example, an insulating substrate 21 (FR-4 substrate), conductive elements 22, and surface mount lines 23. The conductive elements 22 are disposed within and penetrate the insulating substrate 21. The surface mount lines 23 are disposed on the surface of the insulating substrate 21 facing away from the ceramic substrate 10. The surface mount lines 23 include pads 231 disposed on the conductive elements 22 for connecting power semiconductor devices. The conductive elements 22 are preferably copper conductive elements, which can be sintered or soldered to the first copper foil layer 12. The thickness of the sintering or soldering material between them can be 0.05 mm to 0.1 mm, for example, 0.08 mm.

[0042] The conductive element 22 can be used to transmit the larger current required for the operation of the power semiconductor device, while the surface line 23 can be used to transmit smaller currents (e.g., control signals). Furthermore, since the conductive element 22 is connected to the pad 231 and the first copper foil layer 12, the heat generated by the power semiconductor device can be quickly conducted to the ceramic substrate 10 and the metal heat sink 30 via the conductive element 22, achieving rapid heat dissipation.

[0043] The number of conductive elements 22 can be multiple. The first copper foil layer 12 is provided with multiple mutually spaced conductive portions, and the multiple conductive elements 22 are respectively connected to the multiple conductive portions. For example, the number of conductive elements 22 is three, namely a first conductive element 22a, a second conductive element 22b, and a third conductive element 22c; the first copper foil layer 12 is provided with a first conductive portion 12a, a second conductive portion 12b, and a third conductive portion 12c, and the first conductive element 22a, the second conductive element 22b, and the third conductive element 22c are respectively connected to the corresponding first conductive portion 12a, the second conductive portion 12b, and the third conductive portion 12c. The number of conductive elements 22 can also be one.

[0044] Furthermore, the conductive element 22 may be provided with a boss 221, and a pad 231 may be disposed on the boss 221. In this invention, each conductive element 22 may be provided with one or more bosses 221, and each boss 221 may be provided with one or more pads 231; the pads 231 may further extend to the surface of the insulating substrate 21. The conductive element 22 being provided with a boss 221 can increase the wiring area on the surface of the insulating substrate 21, which is beneficial to the miniaturization of the circuit board 20 and the carrier assembly.

[0045] In this invention, the carrier board assembly includes a ceramic substrate 10 disposed between the circuit board 20 and the metal heat sink 30. Electrical insulation is achieved by utilizing a ceramic core plate 11 with excellent electrical insulation properties within the ceramic substrate 10, which improves the voltage withstand performance of the carrier board assembly. The first copper foil layer 12 of the ceramic substrate 10 is connected to the conductive element 22, and the two can jointly transmit large currents, further enhancing the current-carrying capacity of the carrier board assembly.

[0046] The metal heat sink 30 includes interconnected heat sink plates 31 and multiple heat sink columns 32. The heat sink columns 32 can be copper columns with a length of 5mm to 10mm, for example, 6mm; the heat sink plate 31 can be a copper plate with a thickness of 1mm to 5mm, for example, 3mm. The heat sink plate 31 is connected to the second copper foil layer 13 of the ceramic substrate 10. Specifically, the heat sink plate 31 and the second copper foil layer 13 can be sintered or welded together, and the thickness of the sintering or welding material between the heat sink plate 31 and the second copper foil layer 13 is 0.05mm to 0.1mm, for example, 0.08mm.

[0047] The heat dissipation column 32 is sintered or welded to the heat dissipation plate 31. Specifically, the thickness of the sintering or welding material between the heat dissipation plate 31 and the heat dissipation column 32 can be 0.01mm to 0.05mm, for example, 0.02mm. Preferably, as shown in FIG6, the heat dissipation column 32 includes a column body 321 and a conical connecting seat 322. The connecting seat 322 is provided with a connecting surface 323 for sintering or welding to the heat dissipation plate 31; wherein, the surface area of ​​the connecting surface 323 is larger than the cross-section of the column body 321 to increase the connection strength between the heat dissipation column 32 and the heat dissipation plate 31.

[0048] In this invention, the cross-section of the heat dissipation column 32 / column 321 can be circular, square, elliptical, wavy, arc-shaped, etc. This invention does not limit this, but it is preferred to use a heat dissipation column 32 / column 321 with a circular cross-section to facilitate processing.

[0049] In this invention, the material used for sintering or welding can be a metal paste, such as copper paste or silver paste, with copper paste being preferred.

[0050] A second aspect of this invention discloses a method for manufacturing the aforementioned carrier assembly / metal heat sink 30, comprising the following steps:

[0051] S100, sintering or welding material is printed on the surface of the heat sink 31 to place the sintering or welding material on the surface of the heat sink 31 in a local area for connecting the heat sink column 32.

[0052] S200, insert multiple heat dissipation columns 32 into the positioning holes 101 of the fixture plate 100, and fix the fixture plate 100 to the heat dissipation plate 31 so that the heat dissipation columns 32 and the sintered or welded material on the surface of the heat dissipation plate 31 are in close contact with each other under a certain pressure (see Figures 7 and 8, where the sintered or welded material is not shown).

[0053] S300, sintering or welding is performed to connect the heat sink 32 to the heat sink 31;

[0054] S400, remove jig plate 100 to complete the fabrication of the metal radiator.

[0055] The size of the positioning hole 101 of the fixture plate 100 is smaller than that of the connecting seat 322 of the heat dissipation column 32. After the heat dissipation column 32 is inserted into the positioning hole 101, the connecting seat 322 abuts against the fixture plate 100 from above to prevent the heat dissipation column 32 from falling off the fixture plate 100.

[0056] It should be noted that in some embodiments of the present invention, the metal heat sink 30 can be fabricated first, and then the metal heat sink 30 can be connected to the second copper foil layer 13 of the ceramic substrate 10. In other embodiments of the present invention, the heat sink 31 can be connected to the second copper foil layer 13 of the ceramic substrate 10 first, and then the heat sink column 32 can be sintered or connected to the heat sink 31; or, the sintering or welding of the first copper foil layer 12 and the conductive element 22, the second copper foil layer 13 and the heat sink 31, and the heat sink 31 and the heat sink column 32 can be performed simultaneously to further improve the production efficiency of the carrier assembly.

[0057] In some embodiments of the present invention, the heat sink 31 may be a metal-ceramic composite plate, comprising a ceramic plate and a metal plate or metal foil bonded together, the heat sink 32 being sintered or welded to one side of the metal plate or metal foil, and the ceramic plate being connected to the opposite side of the metal plate or metal foil.

[0058] In this invention, the heat dissipation column 32 of the metal radiator 30 is sintered or welded to the heat dissipation plate 31, which helps reduce the material cost and weight of the radiator, thereby promoting the lightweighting of the metal radiator 30 / carrier plate assembly and reducing manufacturing costs. During sintering or welding, the heat dissipation column 32 is positioned and pressure is applied using the jig plate 100, ensuring close contact between the heat dissipation column 32 and the sintering or welding material. This not only facilitates precise and reliable connection of the heat dissipation column 32 to the heat dissipation plate 31, but also allows for simultaneous sintering or welding of multiple heat dissipation columns 32, improving the production efficiency of the metal radiator 30 / carrier plate assembly.

[0059] While the present invention has been described above through embodiments, it should be understood that the above embodiments are only used to exemplify possible implementations of the present invention and should not be construed as limiting the scope of protection of the present invention. All equivalent changes made by those skilled in the art in accordance with the present invention should also be covered by the scope of protection of the claims of the present invention.

Claims

1. A carrier plate assembly with a metal heat sink, characterized in that... include: A ceramic substrate includes a ceramic core plate and a first copper foil layer and a second copper foil layer respectively disposed on two opposite surfaces of the ceramic core plate. A circuit board is disposed on the first surface side of the ceramic substrate; wherein, the insulating substrate of the circuit board is provided with a conductive element connected to the first copper foil layer, and the surface line is provided on the side surface of the insulating substrate facing away from the ceramic substrate, the surface line including pads disposed on the conductive element. A metal heat sink is disposed on the second surface side of the ceramic substrate; the metal heat sink includes a heat sink plate and a plurality of heat sink columns, the heat sink plate is connected to the second copper foil layer of the ceramic substrate, and the heat sink columns are sintered or welded to the heat sink plate.

2. The carrier plate assembly according to claim 1, characterized in that: The heat dissipation column includes a column body and a connecting seat. The connecting seat has a connecting surface that is sintered or welded to the heat dissipation plate. The surface area of ​​the connecting surface is larger than the cross-section of the column body.

3. The carrier plate assembly according to claim 1, characterized in that: The thickness of the sintered or welded material between the heat sink and the heat sink column is 0.01mm to 0.05mm.

4. The carrier plate assembly according to claim 1, characterized in that: The heat dissipation column is a copper column, and the heat dissipation plate is a copper plate with a thickness of 1mm to 5mm.

5. The carrier assembly according to claim 1, characterized in that: The heat sink is sintered or welded to the second copper foil layer, and the thickness of the sintering or welding material between the heat sink and the second copper foil layer is 0.05mm to 0.1mm.

6. The carrier plate assembly according to claim 1, characterized in that: The number of conductive elements is multiple, and the first copper foil layer has multiple mutually spaced conductive portions, with each of the multiple conductive elements connected to the multiple conductive portions respectively.

7. The carrier plate assembly according to claim 1, characterized in that: The conductive component is provided with a boss, and the solder pad is disposed on the boss.

8. The carrier plate assembly according to claim 1, characterized in that: The conductive component is a copper conductive component, which is sintered or welded to the first copper foil layer. The thickness of the sintering or welding material between the conductive component and the first copper foil layer is 0.05 mm to 0.1 mm.

9. The carrier plate assembly according to any one of claims 1 to 8, characterized in that: The material used for sintering or welding is copper paste.

10. A method for manufacturing a metal radiator, the metal radiator comprising a heat dissipation plate and a plurality of heat dissipation columns disposed on the heat dissipation plate; characterized in that, The manufacturing method includes the following steps: S100, printing sintered or welded material on the surface of the heat sink; S200, insert the plurality of heat dissipation columns into the positioning holes of the fixture plate, and fix the fixture plate to the heat dissipation plate so that the heat dissipation columns are in close contact with the sintering or welding material; S300, sintering or welding is performed to connect the heat sink to the heat sink plate; S400, Remove the fixture plate to complete the fabrication of the metal radiator.

Images