Hybrid substrate and method of manufacturing the same

Abstract

The present invention relates to a hybrid substrate and a method of manufacturing the same. Metal plates of different materials having excellent thermal conductivity can be connected to have a thickness advantageous for heat dissipation, and by arranging a metal plate of a material having a low coefficient of thermal expansion between metal plates having a high coefficient of thermal expansion, an effect of preventing warping is obtained when manufacturing a large-area heat spreader.

Description

Technical Field

[0001] This invention relates to a hybrid substrate and a method for manufacturing the same, and more specifically, to a hybrid substrate with a low coefficient of thermal expansion (Low CTE) and a method for manufacturing the same. Background Technology

[0002] Typically, the substrate is formed in a rectangular plate shape and is made of aluminum or copper. Such a substrate can be bonded to the bottom surface of a substrate and used as a heat sink. The substrate can be soldered to the bottom surface of the substrate to facilitate heat dissipation, or it can be bonded using a silver (Ag) paste or similar material with high thermal conductivity.

[0003] However, when both the substrate and the base plate have large areas, the bonding area is wide, which can lead to warping due to differences in thermal expansion. Furthermore, the silver paste melts at high operating temperatures, which can cause substrate warping, defects, etc., and in the case of copper, warping can occur at temperatures of 200°C or higher.

[0004] As a solution, a metal plate made of a material that prevents warping can be applied, but there is a problem of difficulty in ensuring a thickness that is conducive to heat dissipation. Summary of the Invention

[0005] Technical issues

[0006] The purpose of this invention is to provide a hybrid substrate and a method for manufacturing the same, which has a low coefficient of thermal expansion by combining metal plates of different materials with excellent thermal conductivity, and prevents warping when applied over a large area.

[0007] Another object of the present invention is to provide a hybrid substrate and a method for manufacturing the same, wherein the hybrid substrate can ensure a thickness that is conducive to heat dissipation by ensuring the bonding characteristics between metal plates of different materials.

[0008] Technical solution

[0009] According to the features of the present invention for achieving the above-mentioned objectives, the present invention can provide a hybrid substrate comprising: a first metal plate; a second metal plate brazed to the top surface of the first metal plate; and a third metal plate brazed to the bottom surface of the first metal plate, wherein the second metal plate and the third metal plate are formed of the same metal material, and the first metal plate is formed of a metal material different from the second metal plate and the third metal plate.

[0010] The first metal plate can be made of one of the metal plates of Mo, W, CuMo and CuW or a mixture thereof, and the second and third metal plates can each be made of Cu metal plates.

[0011] The first metal plate can be made of a metal plate with a three-layer bonded structure of CuMo / Mo / CuW, and the second metal plate and the third metal plate are each made of Cu metal plate.

[0012] The hybrid substrate may include a brazing filler layer disposed between the first metal plate and the second metal plate, and between the first metal plate and the third metal plate.

[0013] The brazing filler layer may include an Ag layer and a Cu layer formed on the Ag layer.

[0014] The hybrid substrate may also include a seed layer disposed between the first metal plate and the brazing filler layer.

[0015] The seed layer may include a Ti layer and a Cu layer formed on the Ti layer.

[0016] The present invention provides a method for manufacturing a hybrid substrate, the method comprising the following steps: preparing a first metal plate; preparing a second metal plate and a third metal plate, each formed of a metal material different from the first metal plate; forming a seed layer on each of the top and bottom surfaces of the first metal plate; forming a brazing filler layer on the seed layer; respectively placing the second metal plate and the third metal plate on the brazing filler layer; and performing brazing bonding.

[0017] In the step of preparing the first metal plate, a metal plate of Mo, W, CuMo and CuW or a mixture thereof can be prepared as the first metal plate.

[0018] In the step of preparing the first metal plate, a metal plate with a three-layer bonding structure is prepared as the first metal plate. In the three-layer bonding structure, a metal plate made of CuMo is bonded to the top surface of a metal plate made of Mo, and a metal plate made of CuW is bonded to the bottom surface of a metal plate made of Mo.

[0019] In the step of preparing a second metal plate and a third metal plate formed of a metallic material different from the first metal plate, a metal plate made of Cu can be prepared as each of the second metal plate and the third metal plate.

[0020] The step of forming a seed layer on each of the top and bottom surfaces of the first metal plate may include forming a Ti layer on each of the top and bottom surfaces of the first metal plate by sputtering, and forming a Cu layer on the Ti layer by sputtering.

[0021] The step of forming a brazing filler layer on a seed layer may include forming an Ag layer by electroplating the seed layer with Ag and forming a Cu layer by electroplating the Ag layer with Cu.

[0022] The brazing process can be carried out at temperatures between 780°C and 950°C, and additional weight or pressure can be applied to the upper part during the brazing process.

[0023] Beneficial effects

[0024] This invention combines metal plates made of different materials with excellent thermal conductivity to manufacture metal plates with a thickness that facilitates heat dissipation. Furthermore, it allows for the arrangement of metal plates made of materials with low thermal expansion coefficients between metal plates with high thermal expansion coefficients, resulting in metal plates with low thermal expansion coefficients. Therefore, this invention prevents warping during large-area manufacturing and ensures the bonding characteristics between metal plates of different materials through brazing.

[0025] Furthermore, the present invention can ensure a thickness that facilitates heat dissipation by manufacturing different materials in multiple layers, and can maximize the heat dissipation effect because the brazing filler layer used for brazing bonding helps heat transfer, allowing heat to be quickly transferred to the outermost copper plate.

[0026] Therefore, the present invention can be very usefully applied to heat sinks and the like, where conditions such as high heat dissipation and operational reliability are required. Attached Figure Description

[0027] Figure 1 This is a view showing a hybrid substrate according to an embodiment of the present invention.

[0028] Figure 2 It is along Figure 1 The cross-sectional view of the hybrid substrate of the present invention is taken by line AA.

[0029] Figure 3 This is a process diagram illustrating a method for manufacturing a hybrid substrate according to an embodiment of the present invention.

[0030] Figure 4 This is a cross-sectional view showing a hybrid substrate according to another embodiment of the present invention.

[0031] Figure 5 and Figure 6 This is a view illustrating an application example of a hybrid substrate according to an embodiment of the present invention. Detailed Implementation

[0032] In the following, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0033] Figure 1 This is a view showing a hybrid substrate according to an embodiment of the present invention.

[0034] like Figure 1 As shown, the hybrid substrate 1 (hereinafter referred to as substrate 1) according to the present invention is formed by bonding a plurality of metal plates of different materials. For example, substrate 1 includes a first metal plate 10, a second metal plate 20 and a third metal plate 30, and is formed in a structure in which the second metal plate 20 is bonded to the top surface of the first metal plate 10 and the third metal plate 30 is bonded to the bottom surface of the first metal plate 10.

[0035] The second metal plate 20 and the third metal plate 30 are formed of the same metal material, and the first metal plate 10 is formed of a metal material different from that of the second metal plate 20 and the third metal plate 30.

[0036] The first metal plate 10 is formed of a metallic material with a low coefficient of thermal expansion, and the second metal plate 20 and the third metal plate 30, respectively bonded to the top and bottom surfaces of the first metal plate 10, are each formed of a material with excellent thermal conductivity. The substrate 1 with a low coefficient of thermal expansion can be manufactured by bonding the second metal plate 20 and the third metal plate 30, each made of a material with excellent thermal conductivity, to the top and bottom surfaces of the first metal plate 10, which is made of a material with a low coefficient of thermal expansion.

[0037] The first metal plate 10 can be made of one or a mixture of Mo, W, CuMo, and CuW, and the second metal plate 20 and the third metal plate 30 can be made of Cu. Mo, W, CuMo, and CuW each have relatively low coefficients of thermal expansion, while Cu has a relatively high coefficient of thermal expansion. The coefficient of thermal expansion of Cu is 17 ppm / K, and the thermal conductivity of Cu is 393 W / m·K. The coefficient of thermal expansion of CuMo is 7.0 ppm / K, and the thermal conductivity of CuMo is 160 W / m·K. The coefficient of thermal expansion of CuW is 6.5 ppm / K, and the thermal conductivity of CuW is 180 W / m·K.

[0038] As in the embodiment, since the first metal plate 10 is made of CuMo, and the second metal plate 20 and the third metal plate 30 are each made of Cu, the substrate 1 can be formed as a three-layer bonded metal plate structure of Cu / CuMo / Cu. CuMo is used to prevent warping, and Cu is used to ensure thermal conductivity for heat dissipation.

[0039] In this embodiment, the substrate 1 is formed as a three-layer metal plate structure. In this three-layer metal plate structure, a Cu material metal plate with a relatively high coefficient of thermal expansion but high thermal conductivity is bonded to each of the top and bottom surfaces of a CuMo material metal plate with a relatively low coefficient of thermal expansion. Therefore, the warping of the Cu material metal plate can be absorbed by the CuMo material metal plate to reduce the warping phenomenon caused by the difference in the coefficient of thermal expansion at high temperatures.

[0040] If the heat sink is made of only Cu, Cu has a coefficient of thermal expansion of 17 ppm / K, so warping will occur when the heat sink is bonded to the substrate.

[0041] Alternatively, the substrate can be formed into a Cu / CuMo / Cu three-layer structure by immersing a CuMo metal sheet in molten metal to coat each of the top and bottom surfaces of the CuMo metal sheet with a Cu layer, and then rolling the Cu-coated CuMo metal sheet. However, the method of forming a Cu layer on each of the top and bottom surfaces of the CuMo metal sheet by immersing the CuMo metal sheet in molten metal cannot produce substrates with a thickness of 1.0 mm or more.

[0042] Furthermore, in embodiments of the present invention, by bonding a Cu material metal plate to the top and bottom surfaces of a CuMo material metal plate, a three-layer or more layered structure can be formed, thus eliminating the thickness critical point.

[0043] In this embodiment, the CuMo material metal plate used to form the first metal plate 10 can have a thickness of 0.6T, and the Cu material metal plate used to form the second metal plate 20 and the third metal plate 30 can have a thickness of 0.2T. In this case, if the first to third metal plates are formed in a Cu / CuMo / Cu three-layer bonded metal plate structure, a substrate with a thickness of 1.0T (mm) can be manufactured.

[0044] In another embodiment, the first metal plate 10' is formed as a three-layer bonded metal plate structure of CuMo / Mo / CuW, the second metal plate 20 is bonded to the top surface of the first metal plate 10', and the third metal plate 30 is bonded to the bottom surface of the first metal plate 10', so that the substrate can be formed as a five-layer bonded metal plate structure of Cu / CuMo / Mo / CuW / Cu. (Refer to...) Figure 4 Other embodiments are described in detail.

[0045] Figure 2 It is along Figure 1 The cross-sectional view of the hybrid substrate of the present invention is taken by line AA.

[0046] like Figure 2 As shown, the first metal plate 10, the second metal plate 20, and the third metal plate 30 are brazed together.

[0047] The substrate 1 includes a brazing filler layer 40 for brazing the first metal plate 10, the second metal plate 20, and the third metal plate 30. The brazing filler layer 40 is disposed between the first metal plate 10 and the second metal plate 20, and between the first metal plate 10 and the third metal plate 30.

[0048] The brazing filler layer 40 can be one of Ag, Cu, and AgCu alloys. Ag, Cu, and AgCu alloys have high thermal conductivity and transfer heat from the second metal plate 20 to the first metal plate 10 and the third metal plate 30 to promote heat dissipation. Furthermore, Ag, Cu, and AgCu alloys increase the bonding strength between metal plates of different materials. The brazing filler layer 40 can be formed with a thickness greater than or equal to 1 μm and less than or equal to 10 μm. The brazing filler layer 40 can be a thin film with a multilayer structure. For example, the brazing filler layer 40 can include an Ag layer 41 and a Cu layer 42 formed on the Ag layer 41. The Ag layer 41 can have a thickness of 7 μm, and the Cu layer 42 can have a thickness of 3 μm. This allows the Ag layer 41 and Cu layer 42 to have a 7:3 ratio, which increases the bonding strength. The brazing filler layer 40 can be formed by methods such as paste printing or foil deposition.

[0049] The substrate 1 also includes a seed layer 50 disposed between the first metal plate 10 and the brazing filler layer 40. The seed layer 50 is used to improve the wettability of the first metal plate 10 and the brazing filler layer 40. That is, the seed layer 50 helps the brazing filler layer 40 to adhere to the first metal plate 10.

[0050] The seed layer 50 can be one of Ti, Cu, and TiCu alloy. Ti, Cu, and TiCu alloys have good wettability and increase the adhesion of the brazing filler layer 40 to each of the top and bottom surfaces of the first metal plate 10. The seed layer 50 is formed as a thin film. The seed layer 50 can be formed as a thin film with a multilayer structure. For example, the seed layer 50 may include a Ti layer 51 and a Cu layer 52, where each of the top and bottom surfaces of the first metal plate 10 is a thin film coated with Ti layer 51, and Ti layer 51 is a thin film coated with Cu layer 52. Ti layer 51 may have… The thickness of the Cu layer 52 formed on the Ti layer 51 can be such that... The thickness of the seed layer 50 is determined by sputtering.

[0051] The substrate 1 is manufactured by the following steps: forming a seed layer 50 comprising a Ti layer 51 and a Cu layer 52 on each of the top and bottom surfaces of the first metal plate 10; forming a brazing filler layer 40 comprising an Ag layer 41 and a Cu layer 42 on each of the top and bottom surfaces on which the seed layer 50 is formed; placing the second metal plate 20 and the third metal plate 30 on the top and bottom surfaces on which the brazing filler layer 40 is formed, respectively; and brazing them together.

[0052] Figure 3This is a process diagram illustrating a method for manufacturing a hybrid substrate according to an embodiment of the present invention.

[0053] like Figure 2 and Figure 3 As shown, the method for manufacturing a substrate according to the present invention includes the following steps: preparing a first metal plate 10 (S10), preparing a second metal plate 20 and a third metal plate 30 each formed of a metal material different from the first metal plate 10 (S20), forming a seed layer 50 on each of the top surface and bottom surface of the first metal plate 10 (S30), forming a brazing filler layer 40 on the seed layer 50 (S40), disposing the second metal plate 20 and the third metal plate 30 on the brazing filler layer 40 (S50), and performing brazing bonding (S60).

[0054] In step (S10) of preparing the first metal plate, a metal plate selected from Mo, W, CuMo, and CuW, or a mixture thereof, is prepared as the first metal plate 10. For example, a metal plate made of CuMo can be prepared as the first metal plate 10. The first metal plate 10 can be prepared in the thickness range of 0.3T to 0.9T, and for example, a first metal plate 10 with a thickness of 0.6T can be prepared.

[0055] In step (S20) of preparing the second and third metal plates formed of a metallic material different from the first metal plate, a metal plate made of Cu can be prepared as each of the second metal plate 20 and the third metal plate 30. The second metal plate 20 and the third metal plate 30 can each be prepared in a thickness range of 0.25T to 0.55T. For example, the second metal plate 20 and the third metal plate 30 can each be prepared with a thickness of 0.2T.

[0056] In step (S30) of forming a seed layer on each of the top and bottom surfaces of the first metal plate, the steps of forming a Ti layer 51 on each of the top and bottom surfaces of the first metal plate 10 by sputtering and forming a Cu layer 52 on the Ti layer 51 by sputtering can be performed. The Ti layer 51 can be formed by Ti sputtering to have The thickness, and the Cu layer 52 formed on the Ti layer 51 can be formed by Cu sputtering to have The thickness.

[0057] In the step (S40) of forming a brazing filler layer on the seed layer, the steps of forming an Ag layer 41 by electroplating the seed layer 50 with Ag on each of the top and bottom surfaces of the first metal plate 10 and forming a Cu layer 42 by electroplating the Ag layer 41 with Cu can be performed. The Ag layer 41 can be formed to have a thickness of 7 μm by Ag electroplating, and the Cu layer 42 can be formed to have a thickness of 3 μm by Cu electroplating.

[0058] Alternatively, the step (S40) of forming a brazing filler layer on the seed layer can be performed by methods other than electroplating, such as printing Ag or Cu paste, attaching Ag or Cu foil, etc.

[0059] In step (S50) of setting the second metal plate 20 and the third metal plate 30 on the brazing filler layer 40, the second metal plate 20 is set on the brazing filler layer 40 formed on the top surface of the first metal plate 10, and the third metal plate 30 is set on the brazing filler layer 40 formed on the bottom surface of the first metal plate 10, so that a three-layer structure of the second metal plate 20 / first metal plate 10 / third metal plate 30 can be formed.

[0060] The brazing step (S60) is performed at 780°C to 950°C, and top weighting or pressure can be applied during brazing.

[0061] For example, in the brazing bonding step, a laminate of first to third metal plates 10, 20, and 30 is prepared, wherein a second metal plate 20 is disposed on the top surface of the first metal plate 10 on which a seed layer 50 and a brazing filler layer 40 are formed, and a third metal plate 30 is disposed on the bottom surface of the first metal plate 10. The laminate is disposed between an upper pressure fixture and a lower pressure fixture in a brazing furnace, and during heating, the upper and lower pressure fixtures apply pressure to the laminate from its top and bottom surfaces. Alternatively, the laminate is disposed in a brazing furnace, and a weight is placed on the top surface of the laminate to apply pressure from the top of the laminate. The upper weighting or pressure during the brazing bonding step is to achieve a void-free bond.

[0062] The brazing process can be carried out in a brazing furnace under a reducing atmosphere or vacuum, and the brazing filler layer 40 can contain components and compositions that are easy to control at the brazing temperature. An efficient brazing process can be achieved by controlling the heating temperature in the brazing furnace at 780°C or higher, preferably in the range of 780°C to 950°C. As an example, a preferred brazing temperature is 870°C.

[0063] In the substrate 1 of the above embodiment, the first metal plate 10 is made of CuMo material with a low coefficient of thermal expansion, and the second metal plate 20 and the third metal plate 30 are each made of Cu material with high thermal conductivity. Therefore, an example of a substrate forming a three-layer bonded metal plate structure of Cu / CuMo / Cu has been described.

[0064] Furthermore, the first metal plate 10 is made of Mo material, and the second metal plate 20 and the third metal plate 30 are each made of Cu material, so that the substrate 1 can be formed as a Cu / Mo / Cu three-layer bonded metal plate structure. Alternatively, the first metal plate 10 is made of W material, and the second metal plate 20 and the third metal plate 30 are each made of Cu material, so that the substrate 1 can be formed as a Cu / W / Cu three-layer bonded metal plate structure. Alternatively, the first metal plate 10 is made of CuW material, and the second metal plate 20 and the third metal plate 30 are each made of Cu material, so that the substrate 1 can be formed as a Cu / CuW / Cu three-layer bonded metal plate structure.

[0065] In another embodiment, the first metal plate 10 is formed as a three-layer bonded metal plate structure of CuMo / Mo / CuW, the second metal plate 20 is bonded to the top surface of the first metal plate 10, and the third metal plate 30 is bonded to the bottom surface of the first metal plate 10, so that the substrate 1a can be formed as a five-layer bonded metal plate structure of Cu / CuMo / Mo / CuW / Cu.

[0066] Figure 4 This is a cross-sectional view showing a hybrid substrate according to another embodiment of the present invention.

[0067] like Figure 4 As shown, in substrate 1a according to another embodiment of the present invention, the first metal plate 10' is formed as a three-layer composite structure of CuMo metal plate 10b / Mo metal plate 10a / CuW metal plate 10c, and the second metal plate 20 bonded to the top surface of the first metal plate 10' and the third metal plate 30 bonded to the bottom surface of the first metal plate 10' are each made of Cu metal plate.

[0068] The first metal plate 10' is manufactured by the following steps: forming a seed layer 50 comprising a Ti layer 51 and a Cu layer 52 on each of the top and bottom surfaces of the Mo metal plate 10a; forming a brazing filler layer 40 comprising an Ag layer 41 and a Cu layer 42 on each of the top and bottom surfaces on which the seed layer 50 is formed; placing a CuMo metal plate 10b and a CuW metal plate 10c on the top and bottom surfaces on which the brazing filler layer 40 is formed on the Mo metal plate 10a, respectively; and brazing them together.

[0069] Furthermore, the substrate 1a can be manufactured by: forming a seed layer 50 comprising a Ti layer 51 and a Cu layer 52 on each of the top and bottom surfaces of the first metal plate 10' (which is formed as a three-layer composite structure of CuMo metal plate 10b / Mo metal plate 10a / CuW metal plate 10c); forming a brazing filler layer 40 comprising an Ag layer 41 and a Cu layer 42 on each of the top and bottom surfaces on which the seed layer 50 is formed; placing the second metal plate 20 and the third metal plate 30 on the top and bottom surfaces on which the brazing filler layer 40 is formed, respectively; and performing brazing bonding.

[0070] The advantage is that the aforementioned five-layer Cu / CuMo / Mo / CuW / Cu bonded metal plate structure can be manufactured to a thickness of 3.0 mm or more, and when manufactured as a multilayer with five or more layers, there is no thickness critical point for the bonded metal plate structure. Therefore, it is easy to apply the bonded metal plate structure to heat sinks where a favorable thickness for heat dissipation must be ensured.

[0071] The aforementioned substrates 1 and 1a are integrally formed by brazing copper sheets to each of the top and bottom surfaces of a metal plate or a stack of metal plates of Mo, W, CuMo, and CuW. Therefore, substrates 1 and 1a can possess excellent thermal conductivity, a reduced coefficient of thermal expansion, minimize thermal stress, and exhibit excellent bonding between metals of different materials to meet requirements for reliability and high heat dissipation.

[0072] Furthermore, since the substrate 1 and substrate 1a are integrated by stacking metals of various different materials, the substrate 1 and substrate 1a can be manufactured to a desired thickness of 3 mm or greater without a thickness critical point, and the heat dissipation effect can be maximized.

[0073] The aforementioned substrate 1 and substrate 1a each have a strength of 150 MPa or higher, a warpage of 0.05 mm or less (when welded to the bottom surface of a ceramic substrate at approximately 250 °C), and thermal properties, for example, a coefficient of thermal expansion in the range of 6.8 to 12 ppm / K and a thermal conductivity in the range of 220 to 280 W / m·K.

[0074] The aforementioned substrates 1 and 1a can function as heat sinks by being bonded to the bottom surface of the ceramic substrate constituting the power module using solder or silver (Ag) paste. Here, the ceramic substrate can be an AMB substrate or a DBC substrate.

[0075] Figure 5 and Figure 6 This is a view illustrating an application example of a hybrid substrate according to an embodiment of the present invention.

[0076] like Figure 5 As shown, substrates 1' and 1" can be formed as a three-layer bonded metal plate structure of Cu / CuMo / Cu or a five-layer bonded metal plate structure of Cu / CuMo / Mo / CuW / Cu. Each of the substrates 1' and 1" can be manufactured by brazing through a seed layer 50 and a brazing filler layer 40. The side surfaces of the substrates can then be machined by wire cutting to form bolt holes h at the desired locations on the substrates. After forming the bolt holes h, surface pickling is performed to manufacture the desired shape.

[0077] The coefficients of thermal expansion of substrates 1' and 1" manufactured by the above method are in the range of 6.8 to 12 ppm / K, which are lower than those of copper or aluminum, which have a coefficient of thermal expansion of 17 ppm / K or higher. Therefore, substrates 1' and 1" can replace conventional heat sinks made of copper (Cu) or aluminum (Al) to minimize thermal stress and prevent warping in high-temperature environments. Substrates 1' and 1" can be manufactured in various shapes.

[0078] also, Figure 5 The shape of the substrate 1' shown can be applied to RF communication. Figure 6 The shape of the substrate 1 shown can be applied to the heat sink of the power module.

[0079] In addition to general heat sinks, the substrates manufactured with low coefficients of thermal expansion can also be used as substrates for communication, heat sinks for power modules, and filler components (supports and spacers for supporting or connecting substrates) for DSC power modules.

[0080] Preferred embodiments of the invention are disclosed in the accompanying drawings and description. Specific terminology is used herein, but these terms are for descriptive purposes only and do not limit the meaning of the terms used in the claims or the scope of the invention. Therefore, those skilled in the art will understand that various modifications and other equivalent embodiments can be made from the embodiments. Accordingly, the true technical scope of the invention should be determined by the technical spirit of the foregoing claims.

Claims

1. A hybrid substrate, the hybrid substrate comprising: First metal plate; A second metal plate is brazed to the top surface of the first metal plate; as well as A third metal plate, which is brazed to the bottom surface of the first metal plate, The second metal plate and the third metal plate are formed of the same metal material, and the first metal plate is formed of a metal material different from that of the second metal plate and the third metal plate. The first metal plate is made of a metal plate with a three-layer composite structure of CuMo metal plate and CuW metal plate, wherein the CuMo metal plate is bonded to the top surface of the Mo metal plate, the CuW metal plate is bonded to the bottom surface of the Mo metal plate, and the second metal plate and the third metal plate are each made of Cu metal plate.

2. The hybrid substrate according to claim 1, wherein the hybrid substrate includes a brazing filler layer disposed between the first metal plate and the second metal plate and between the first metal plate and the third metal plate.

3. The hybrid substrate according to claim 2, wherein, The brazing filler layer includes an Ag layer and a Cu layer formed on the Ag layer.

4. The hybrid substrate according to claim 3, wherein the hybrid substrate further comprises a seed layer disposed between the first metal plate and the brazing filler layer.

5. The hybrid substrate according to claim 4, wherein, The seed layer includes a Ti layer and a Cu layer formed on the Ti layer.

6. A method for manufacturing a hybrid substrate, the method comprising the following steps: Preparation of the first metal plate; Prepare a second metal plate and a third metal plate, each made of a metallic material different from the first metal plate; A seed layer is formed on each of the top and bottom surfaces of the first metal plate; A brazing filler layer is formed on the seed crystal layer; The second metal plate and the third metal plate are respectively disposed on the brazing filler layer; as well as Perform brazing. In the step of preparing the first metal plate, a metal plate with a three-layer bonding structure is prepared as the first metal plate. In the three-layer bonding structure, a metal plate made of CuMo is bonded to the top surface of a metal plate made of Mo, and a metal plate made of CuW is bonded to the bottom surface of a metal plate made of Mo. In the step of preparing the second metal plate and the third metal plate, a metal plate made of Cu is prepared as each of the second metal plate and the third metal plate.

7. The method according to claim 6, wherein, The step of forming the seed layer on each of the top and bottom surfaces of the first metal plate includes the following steps: A Ti layer is formed on each of the top and bottom surfaces of the first metal plate by sputtering; and A Cu layer is formed on the Ti layer by sputtering.

8. The method according to claim 6, wherein, The step of forming the brazing filler layer on the seed layer includes the following steps: An Ag layer is formed by electroplating the seed crystal layer with Ag; and A Cu layer is formed by electroplating an Ag layer with Cu.

9. The method according to claim 6, wherein, The brazing process is carried out at 780°C to 950°C, and the upper part is weighted or pressurized during the brazing process.

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