Metal-ceramic bonded substrate and manufacturing method thereof

Abstract

To provide a metal-ceramic bonded substrate and a manufacturing method thereof capable of smoothly attaching a plurality of fins to a base plate without damaging a ceramic plate.SOLUTION: A metal-ceramic bonded substrate 1 in which a base plate 20 having a radiation fin 13 is bonded to one surface of a ceramic plate 15. The radiation fin 13 is composed of a plurality of fin members 21 attached to the base plate 20. At the proximal end portion of the fin member 21, a wide portion 46 protruding outward from the side surface of the fin member 21 is formed, and the surface side of the wide portion 46 is brazed to the base plate 20, and the fin member 21 is attached to the base plate 20.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a metal / ceramic bonding substrate provided with heat dissipation fins for cooling heat generating elements such as semiconductor chips, and a method for manufacturing the same. [Background technology]

[0002] Electronic components that generate a lot of heat, such as power semiconductor chips, are cooled by dissipating the heat to heat dissipation fins. Currently, metal-ceramic bonded substrates that have an integrated structure of a base plate (base board) and circuit board with heat dissipation fins often use pin-fin-shaped heat dissipation fins that are designed for water cooling, but there is also a considerable demand for heat dissipation fins with an air-cooled structure. In the case of heat dissipation fins with an air-cooled structure, the surface area of ​​the fins needs to be large in order to achieve heat exchange efficiency. Specifically, tall, plate-shaped fins (30 mm or longer) are required.

[0003] When using the molten metal bonding method to create an integrated metal (aluminum)-ceramic bonded substrate, it is necessary to set a certain taper angle on the fins to allow the aluminum fins to be released from the mold, making it difficult to narrow the fin spacing. Furthermore, it is difficult to supply molten metal during solidification, making it difficult to form plate-shaped fins longer than 30 mm.

[0004] For this reason, for example, Patent Document 1 discloses a technique for attaching multiple fins to a base plate by caulking them with a press. Patent Document 2 discloses a technique for inserting fins into molten metal and solidifying them to attach the fins. Patent Document 3 discloses a technique for brazing fins to a base plate to create heat dissipation fins. The technique in Patent Document 3 uses induction heating to melt the brazing material. Patent Document 4 discloses a technique for fitting fins into recesses and brazing them. Patent Document 5 discloses a technique for brazing L-shaped fins to a base plate. Patent Document 6 discloses a technique for brazing U-shaped fins to a base plate. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2019-166547 [Patent Document 2] Japanese Patent Application Publication No. 2018-186141 [Patent Document 3] Japanese Patent Application Publication No. 2018-94558 [Patent Document 4] Japanese Patent Application Publication No. 10-71462 [Patent Document 5] Japanese Patent Application Laid-Open No. 2002-50723 [Patent Document 6] Japanese Patent Application Laid-Open No. 2001-217357 Summary of the Invention [Problem to be solved by the invention]

[0006] However, with the technique of attaching multiple fins to a base plate by crimping, as in Patent Document 1, the fins are sandwiched horizontally, so a portion of the base plate needs to be deformed by applying a strong load to obtain strength. Therefore, when applied to, for example, an integrated metal-ceramic bonded substrate with a ceramic plate, there is a high possibility that the ceramic substrate will crack. Furthermore, with the technique of attaching fins by solidifying molten metal, as in Patent Document 2, it is difficult to control the process so that the fins do not melt. Furthermore, with the technology of brazing fins by induction heating as in Patent Document 3, manufacturing costs increase due to the need to prepare a clad material in which a magnetic body is formed on the base member for induction heating, and since induction heating tends to result in large temperature distribution depending on the location, it is difficult to uniformly control the bonding state of the fins. Also, since the ends of the fins are bonded, the bonding area is small, which makes it prone to problems such as insufficient spreading of the brazing material and the fins coming off, raising concerns about reduced bonding reliability. The method of bending a single metal plate into a zigzag or U-shaped cross section to form a fin body, as in Patent Document 4 or Patent Document 6, requires dimensional precision in the bending process and makes it difficult to maintain a constant distance between the fins. Also, if there is a connecting portion at the top, there is a risk that the heat dissipation efficiency will be reduced compared to plate-shaped fins without a connecting portion, especially in the case of air cooling. In the method of brazing L-shaped fins as in Patent Document 5, it is difficult to maintain a precise distance between the fins, and since the L-shape has a base, a certain distance is required, making it difficult to reduce the distance between the fins. Also, a structure in which heat dissipation fins are joined together with spacer protrusions is shown, but there is a problem in that forming fins with this structure is expensive.

[0007] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a metal-ceramic bonding substrate in which a plurality of fins can be smoothly attached to a base plate without damaging the ceramic plate, and a method for manufacturing the same. [Means for solving the problem]

[0008] In order to achieve the above object, a metal-ceramic bonding substrate is provided in which a base plate having heat dissipation fins is bonded to one surface of a ceramic plate, the heat dissipation fins being made of a plurality of fin members attached to the base plate, and the base end of the fin member has a plurality of fin members protruding outward from both sides of the fin member. Has a trapezoidal cross-sectional shape A wide part is formed, The base plate is formed with a plurality of receiving portions each having a trapezoidal cross-sectional shape corresponding to the cross-sectional shape of the wide portion, The surface side of the wide portion is the base plate The receiving portion of and the fin member is attached to the base plate, thereby providing a metal-ceramic bonding substrate.

[0009] The aforementionedThe fin member may be made of aluminum or an aluminum alloy. The base plate may be made of aluminum or an aluminum alloy. A metal circuit plate may be formed on the other surface of the ceramic plate. The metal circuit plate may be made of aluminum or an aluminum alloy. A reinforcing member may be formed inside the base plate.

[0010] According to the present invention, there is also provided a method for manufacturing a metal-ceramic bonding substrate in which a base plate having heat dissipation fins is bonded to one surface of a ceramic plate, the heat dissipation fins being made of a plurality of fin members attached to the base plate, and the base end of the fin member is provided with a plurality of fin members protruding outward on both sides from the side surfaces of the fin member. Has a trapezoidal cross-sectional shape A wide portion is formed on the base plate. The cross-sectional shape of the wide portion is a trapezoid that corresponds to the cross-sectional shape of the wide portion. A plurality of receptors are formed, The method for producing a metal / ceramic bonding substrate includes brazing the surface side of the wide portion in a state where the surface side of the wide portion is in contact with the receiving portion.

[0011] The plurality of fin members may be arranged in parallel using a jig, and then the surface sides of the wide portions of the plurality of fin members may be abutted against the receiving portions and brazed. The fin members may be made of aluminum or an aluminum alloy. The fin members may be extruded material. The base plate may be made of aluminum or an aluminum alloy. A metal circuit plate may be provided on the other surface of the ceramic plate. The metal circuit plate may be made of aluminum or an aluminum alloy. A reinforcing member may be formed inside the base plate. The ceramic plate and the base plate may be joined by a molten metal joining method. The ceramic plate and the metal circuit plate may be joined by a molten metal joining method. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a metal / ceramic bonding substrate in which a plurality of fins can be smoothly attached to a base plate without damaging the ceramic plate, and a method for manufacturing the same. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a cross-sectional view showing the structure of a metal-ceramic bonding substrate according to an embodiment of the present invention. [Figure 2] FIG. 2 is an explanatory view (cross-sectional view) showing an example of a method for manufacturing a metal / ceramic bonding substrate according to an embodiment of the present invention, showing a state in which a ceramic plate and a reinforcing member are set in a mold and molten metal is poured into the mold. [Figure 3] FIG. 2 is a perspective view of the semi-finished substrate as viewed from the base plate side. [Figure 4] 4 is an enlarged view showing the shape of the cross section XX in FIG. 3 of the semi-finished substrate. [Figure 5] FIG. [Figure 6] FIG. 4 is a partially enlarged view (cross-sectional view) showing the shape of the base end portion of the fin member. [Figure 7] FIG. 10 is a perspective view of a jig for arranging a plurality of fin members in parallel. [Figure 8] 10 is an explanatory diagram (side view) of a state in which a brazing material is applied to a receiving portion formed on a base plate. FIG. [Figure 9] FIG. 10 is an explanatory diagram (perspective view) showing a state in which a plurality of fin members arranged in parallel and held in a jig are placed on a base plate (semi-finished substrate) with their base ends facing downward. [Figure 10] 10 is an explanatory view (cross-sectional view) of a state in which a plurality of fin members are brazed while being held by a jig. FIG. [Figure 11] 10 is an explanatory diagram (cross-sectional view) of a state in which the surface side of the wide portion is in contact with the receiving portion and the surface side of the wide portion is brazed to the receiving portion. FIG. [Figure 12] FIG. 10 is an explanatory view (cross-sectional view) showing an example of a method for producing a metal / ceramic bonding substrate according to another embodiment of the present invention, showing a state in which a ceramic plate is set in a mold and molten metal is poured into it. DETAILED DESCRIPTION OF THE INVENTION

[0014] An embodiment of the present invention will now be described with reference to the accompanying drawings. In this specification, substantially similar components are designated by the same reference numerals, and redundant description will be omitted.

[0015] <Metal-ceramic bonded substrate> As shown in Fig. 1, a metal-ceramic bonding substrate 1 according to an embodiment of the present invention has heat dissipation fins 13 on one surface (the lower surface of ceramic plate 15 in Fig. 1) of a (for example, substantially rectangular) ceramic plate 15, with a base plate 20 interposed therebetween. The metal-ceramic bonding substrate 1 has one or more metal circuit plates 12 bonded to the other surface (the upper surface of ceramic plate 15 in Fig. 1) of ceramic plate 15. In the illustrated embodiment, two (for example, substantially rectangular) metal circuit plates 12 are bonded to the upper surface of ceramic plate 15.

[0016] Since electronic components that generate a large amount of heat, such as power semiconductor chips, are mounted on the metal circuit plate 12, the metal circuit plate 12 is preferably made of a metal with excellent electrical and thermal conductivity, such as a single metal such as copper or aluminum, or an alloy such as a copper alloy or an aluminum alloy. The electronic components mounted on the metal circuit plate 12 are heat-generating bodies, and the heat is released to the heat dissipation fins 13 provided on the opposite side of the ceramic plate 15 via the base plate 20, thereby cooling the electronic components.

[0017] The ceramic plate 15 is preferably made of an oxide containing alumina, silica, or the like as a main component, or a non-oxide containing aluminum nitride, silicon nitride, silicon carbide, or the like as a main component.

[0018] The heat dissipation fins 13 are made of a plurality of fin members 21 attached to a base plate 20. The heat dissipation fins 13 (the plurality of fin members 21) are preferably made of aluminum or an aluminum alloy, which has excellent thermal conductivity and is easy to extrude. The base plate 20 can be joined to the ceramic plate 15 by the molten metal joining method described below, and is preferably made of aluminum or an aluminum alloy (such as A6063 alloy) with high thermal conductivity. 1 is an example in which the base plate 20 is made up of a metal layer 17 and a reinforcing member 16, and the reinforcing member 16 for suppressing warpage of the base plate 20 is formed (bonded) inside the metal layer 17. The main surface (plate surface) of the reinforcing member 16 is positioned approximately parallel to the main surface (plate surface) of the ceramic plate 15. The material of the reinforcing member 16 is preferably a ceramic substrate mainly composed of aluminum nitride or silicon nitride, a plate material made of carbon steel, or the like. Metal layer 17 is preferably made of, for example, aluminum or an aluminum alloy so that heat generated in electronic components (heat generating elements) mounted on metal circuit board 12 can be smoothly conducted to fin member 21.

[0019] The fin members 21 are arranged parallel to one another at predetermined intervals on the outer surface of the base plate 20 (the surface of the base plate 20 opposite to the surface bonded to the ceramic plate 15 (the underside of the metal layer 17 in FIG. 1 )), allowing heat to be dissipated over the entire surface of the fin members 21. As will be described later, the base end of the fin member 21 is formed with wide portions 46 that protrude outward on both sides from the side surfaces of the fin member 21, and the surface side of the wide portions 46 is brazed with the surface side of the wide portions 46 in contact with (the receiving portion 40 of) the base plate 20, thereby attaching the fin member 21 to the base plate 20.

[0020] <Metal-ceramic substrate manufacturing method> Next, an example of a manufacturing method for the metal-ceramic bonding substrate 1 according to the embodiment of the present invention will be described. As an example, a manufacturing method will be described using a base plate 20 having a laminated structure made up of a metal circuit plate 12, a ceramic plate 15, and a metal layer 17 having a reinforcing member 16 formed therein, as shown in Fig. 1.

[0021] As shown in FIG. 2, first, a ceramic plate 15 and a plate-shaped reinforcing member 16 (ceramic plate in FIG. 2) made of, for example, ceramic material are set in a cavity 33 of a carbon mold 32 consisting of an upper mold 30 and a lower mold 31 with a predetermined gap in advance so that their plate surfaces are approximately parallel. In this mold 32, the ceramic plate 15 shown at the top in FIG. 1 is placed on the lower side of the cavity 33 of the mold 32, and the reinforcing member 16 shown at the bottom in FIG. 1 is placed on the upper side. Although not shown, the end of the reinforcing member 16 is sandwiched and held between the upper mold 30 and the lower mold 31 in the front-to-back direction in FIG. 2 (the direction perpendicular to the paper surface). The ceramic plate 15 is placed in a predetermined position by being placed on a protrusion (not shown) of the lower mold 31.

[0022] After the ceramic plate 15 and the reinforcing member 16 (ceramic plate) are set in the cavity 33 of the mold 32 with a predetermined gap between them, a predetermined amount of aluminum raw material is poured into the tank 35. The lid 36 is then placed on the tank 35, and the mold 32 is transported to a heating furnace (not shown) and heated in a nitrogen atmosphere to a temperature above the melting point of aluminum. Once the aluminum is melted, the tank 35 is pressurized with N2 gas at a pressure of approximately 100 kPa, and the aluminum from the tank 35 is transferred through the runner 34 to the cavity 33, filling the outside of the reinforcing member 16 (above the reinforcing member 16 in Figure 2), the gap between the ceramic plates 15, and the outside of the ceramic plate 15 (below the ceramic plate 15 in Figure 2). During transfer, the aluminum passes through a narrow section (not shown) in the runner 34 to remove oxides from the aluminum surface before being transferred to the cavity 33.

[0023] With the entire cavity 33 filled with aluminum in this way, a water-cooled copper block (not shown) is brought into contact with the side of the mold 32 (the left side of the mold 32 in FIG. 2) at a position away from the tank portion 35, and heat is removed from the side of the mold 32, thereby directionally solidifying the aluminum filled in the cavity 33. At this time, N2 gas is pressurized from the tank portion 35 to about 100 kPa, and aluminum is replenished to prevent shrinkage cavities due to solidification shrinkage of the aluminum.

[0024] The aluminum in the void 33 is then cooled to room temperature, the mold 32 is dismantled, and a bonded body is taken out in which the aluminum, ceramic plate 15, and reinforcing member 16 are bonded together by molten metal bonding. The bonded body thus obtained is subjected to post-processing such as cutting off excess aluminum from the runners and the like, and a ceramic plate 15 having a circuit metal plate on one side is formed on the surface of the base plate 20, which has a laminated structure in which the reinforcing member 16 is bonded inside the metal layer 17. Note that through-holes, for example, with a diameter of about 6 mm, may be machined in four locations near the four corners of the base plate 20 as mounting holes for a housing or the like. Note that the plate surfaces of the ceramic plate 15 and the reinforcing member 16 (ceramic plate in this example) are positioned parallel to each other.

[0025] Furthermore, the aluminum (metal layer 17) bonded to the outside of the reinforcing member 16 becomes the base plate 20 on which a plurality of receiving portions 40 are formed when the bonded body is manufactured using the mold 32. Furthermore, as shown in Figures 3 and 4, the surface shape of the base plate 20 has recesses formed between the upper ends 41 of the adjacent receiving portions 40. That is, on the surface corresponding to the gap 33 of the upper mold 30 of the mold 32 in Figure 2, convex shapes and concave shapes, etc., are formed which correspond to the multiple receiving portions 40 (not shown) and the recesses between the upper ends 41 of each adjacent receiving portion 40 (not shown).

[0026] Then, a mask (photoresist) of a predetermined circuit shape is applied to the surface of the aluminum circuit metal plate bonded to the outside of ceramic plate 15, and an aqueous solution containing iron chloride is sprayed as an etching solution to dissolve (etch) unnecessary portions such as the aluminum at the edges of the ceramic plate and between the circuit patterns, thereby forming metal circuit plate 12. After etching, the unnecessary masking material (photoresist) is peeled off with a chemical solution. In this way, substrate semi-finished product 2 is produced. Furthermore, Ni plating such as electric Ni plating or electroless Ni-P plating may be applied to the surface of the metal circuit board 12 in order to mount (bond) electronic components by soldering, etc. Furthermore, when mounting (bonding) electronic components by silver sintering, electric Au plating or electroless Au plating may be further applied to the Ni-plated surface.

[0027] Table 1 shows examples 1 to 4 of combinations of manufacturing conditions for semi-finished substrate 2. In Table 1, the aluminum material is the composition of aluminum used to bond ceramic plate 15 and reinforcing member 16 and to form circuit metal plate and metal layer 17, and the numerical values ​​indicate mass %. That is, examples 1 and 2 are pure aluminum containing 99.9 mass % or more of Al, and examples 3 and 4 are aluminum alloys containing 0.04 mass % of Mg and 0.04 mass % of Si, with the remainder being Al. The thickness of each layer is the thickness (mm) of the aluminum circuit metal plate bonded to the outside of the ceramic plate 15, the ceramic plate 15, the aluminum metal layer 17 between the ceramic plate 15 and the reinforcing member 16, the reinforcing member 16, and the aluminum metal layer 17 bonded to the outside of the reinforcing member 16 (between the reinforcing member 16 and the surface of the outer periphery of the base plate 20 excluding the areas where the receiving portion 40 and the recesses between the upper ends of adjacent receiving portions are formed). The material of the ceramic plate 15 and the material of the reinforcing member 16 (ceramic plate in this example) are also listed. That is, the ceramic plate 15 and the reinforcing member 16 in Examples 1 and 3 are made of aluminum nitride, while the ceramic plate 15 and the reinforcing member 16 in Examples 2 and 4 are made of silicon nitride. The outer dimensions of each layer indicate the outer dimensions (all rectangular, short side (mm) x long side (mm)) of the aluminum circuit metal plate bonded to the outside of the ceramic plate 15, the ceramic plate 15, the aluminum metal layer 17 between the ceramic plate 15 and the reinforcing member 16, the reinforcing member 16, and the aluminum metal layer 17 bonded to the outside of the reinforcing member 16. The bonding methods are all the well-known molten aluminum bonding method described above. The metal layer 17 surrounds the reinforcing member 17 and is bonded to it.

[0028] [Table 1]

[0029] As shown in FIGS. 3 and 4 , the base plate 20 (metal layer 17) joined to the outer side of the reinforcing member 16 in the semi-finished substrate 2 has a plurality of parallel groove-shaped receiving portions 40 extending in the direction of the short side of the semi-finished substrate 2. Each receiving portion 40 has a trapezoidal cross-sectional shape that widens outward (upward in FIGS. 3 and 4 ). In the illustrated embodiment, the bottom width L1 is 1 mm, the top width (the distance between the upper ends 41 of one receiving portion 40) L2 is 3 mm, and the depth H2 is 2 mm. The groove-shaped receiving portions 40 may have any shape that can accommodate the widened portions 46 of the base ends of the fin members 21 (described below), and may have a cross-sectional shape such as a rectangle or a square. A trapezoidal cross-section is preferable because it facilitates accommodating the widened portions 46 of the fin members 21. Furthermore, when brazing the fin member 21 to the receiving portion 40 (described later), in order to ensure good contact when the fin member 21 is placed in the receiving portion 40, it is preferable that the cross-sectional shape of the receiving portion 40 corresponds to the cross-sectional shape of the fin member 21. It is practically preferable that the width L1 of the bottom portion be in the range of 1 to 10 mm, the width L2 of the top portion be in the range of 1 to 20 mm, and the depth be in the range of 0.5 to 3 mm. The length L3 of each receiving portion 40 in the short side direction of the semi-finished substrate 2 is set to 70 mm. The length L3 of each receiving portion 40 depends on the size of the fin member 21, but is preferably in the range of 30 to 150 mm, for example.

[0030] Furthermore, the distance L4 between the upper ends 41 of the adjacent receiving portions 40 is set to 2 mm. The distance between the upper ends 41 of the receiving portions 40 is preferably in the range of 0 to 10 mm. 4, an inverted triangular recess is formed between the upper ends 41 of adjacent receiving portions 40 of the base plate 20 (metal layer 17). However, the recess does not have to be formed between the upper ends 41, and the shape between the upper ends 41 is not particularly specified. It is sufficient that the receiving portion 40 and the fin member 21, which will be described later, can be brazed. Furthermore, by making the distance between the upper ends 41 of the receiving portions 40 0 ​​mm or sufficiently small, the gap between the adjacent fin members 21 can be made small.

[0031] 5 and 6, the substantially plate-shaped fin member 21 attached to the base plate 20 has a rectangular parallelepiped fin main body 45, and wide portions 46 are formed at the base end of the fin member 21 (fin main body 45), protruding outward on both sides from the side surfaces of the fin member 21 (fin main body 45). The wide portions 46 protruding outward on both sides from the side surfaces of the fin member 21 are portions formed at the base end of the rectangular parallelepiped fin main body 45, and have a thickness greater than the thickness T of the fin main body 45, as shown in FIG. 6. It is preferable that the wide portions 46 have the same shape in a cross section perpendicular to the longitudinal direction of the fin member 21. In the illustrated embodiment, the fin member 21 (fin main body 45) has a width L10 of 70 mm, a height H10 of 30 mm, and a thickness T of 1 mm. It is preferable that the length L10 of the fin main body 45 is in the range of, for example, 30 to 150 mm, and the height H10 is in the range of 20 to 50 mm.

[0032] The surface side of the wide portion 46 (the side that abuts against the receiving portion 40 of the base plate 20, and the lower side of the wide portion 46 in Figures 5 and 6) has a trapezoidal cross-sectional shape that widens outward (upward in Figures 5 and 6), and in the illustrated embodiment, the width L11 of the bottom is 1 mm, the distance (maximum width) L12 between the end portions 47 that form the widest portions is 3 mm (each protruding length L13 at the top is 1 mm), and the height H11 from the widest portion (end portion 47) to the bottom is 2 mm. In other words, the surface side of the wide portion 46 and the receiving portion 40 have the same trapezoidal cross-sectional shape. The wide portion 46 of the fin member 21 may have a cross-sectional shape such as a rectangle or a square, etc. A trapezoidal cross section is preferable because it makes it easier to accommodate the base plate 20 in the receiving portion 40. It is practically preferable that the width L11 of the bottom is 1 to 10 mm, the width L12 of the top is 1 to 20 mm (each overhang length L13 of the top is 1 to 8 mm), and the height H11 is 0.5 to 3 mm.

[0033] 7, the fin member 21 can be held by a jig 50. The jig 50 has a pair of support portions 51, 51, which are fixed in parallel at a predetermined interval that is narrower than the width L10 (70 mm) of the fin member 21 (fin main body portion 45) by a bar member 52. The height of the support portions 51, 51 is set to be approximately the same as the height H10 (30 mm) of the fin member 21.

[0034] A plurality of slots 53 are provided at regular intervals on the inner surfaces of the support portions 51, 51 facing each other. The slots 53 are set to a width that allows the fin main body 45 to pass through but not the wide portion 46. Therefore, as shown in FIG. 7 , the fin member 21 can be supported by the jig 50 by placing the fin member 21 with the wide portion 46 facing up and inserting both sides of the fin main body 45 from above into the paired slots 53, 53 provided on the inner surfaces of the support portions 51, 51. Note that because the slots 53 are wide enough to allow the fin main body 45 to pass through but not the wide portion 46, inserting both sides of the fin main body 45 from above into the slots 53, 53 in this manner causes the wide portion 46 to be caught and supported by one end of the slots 53 (the upper end of the slots 53 in the state shown in FIG. 7 ). At one end of each slot 53, a recess 54 is provided to receive the back side of the wide portion 46 (the side opposite to the front side of the wide portion 46, i.e., the side that does not abut against the receiving portion 40 of the base plate 20; in Figures 5 and 6, this is the upper side (above the end 47) of the wide portion 46). In this way, by supporting the fin members 21 in each of the multiple slots 53 provided opposite each other at regular equal intervals on the inner surface of the support portions 51, 51, it is possible to hold the multiple fin members 21 in a state where they are arranged in parallel with each other in the jig 50.

[0035] In the method for manufacturing metal / ceramic bonding substrate 1 according to the embodiment of the present invention, brazing filler metal 55 is applied in advance to receiving portion 40 of semi-finished substrate 2, as shown in FIG. For example, when the base plate and fin members are made of aluminum or an aluminum alloy, commercially available brazing filler metals such as Al-Si and Al-Si-Mg brazing filler metals can be used. Suitable examples include an Al-Si brazing filler metal with a composition of 10% by mass Si and the balance Al (joining conditions: use of a small amount of flux (NOCOLOC manufactured by SOLVAY), N2 atmosphere, joining temperature 590°C), and an Al-Si-Mg brazing filler metal with a composition of 7.5% by mass Si, 1.0% by mass Mg, and the balance Al (joining conditions: fluxless, N2 atmosphere or vacuum (oxygen concentration 100 ppm or less in N2), joining temperature 590°C). In Examples 1 to 4 of the present application, the brazing filler material was an Al-Si-Mg brazing filler paste having a composition of 7.5 mass% Si, 1.0 mass% Mg, and the remainder Al, as described above, which was applied to the receiving portion 40 using a dispenser (without using flux) to form the brazing filler material 55 on the receiving portion 40 of the base plate 20.

[0036] Then, as shown in FIG. 9 , with the multiple fin members 21 arranged in parallel on the jig 50, the front side of the wide portion 46 of each fin member 21 (the underside, bottom surface 48, and / or side surface 49 of the wide portion 46 in FIGS. 5 and 6 ) is brought into contact with the bottom surface and / or side surface of each of the multiple receiving portions 40 provided on the base plate 20 of the semi-finished substrate 2. In this case, as shown in FIG. 7 , the fin members 21 are held in the jig 50 with the wide portions 46 facing up, and the multiple fin members 21 are arranged in parallel in each slot portion 53. Then, with the base plate 20 of the semi-finished substrate 2 pressing from above the wide portions 46 of the multiple fin members 21 arranged in parallel on the jig 50, the jig 50 and the semi-finished substrate 2 are turned upside down together. This allows the multiple fin members 21 held by the jig 50 to be arranged in parallel on the base plate 20 of the semi-finished substrate 2, as shown in FIGS. 9 and 10 . In this manner, by arranging the plurality of fin members 21 in parallel on the base plate 20 of the semi-finished substrate 2, the wide portions 46 of the fin members 21 are oriented so that they face downward, and the surface side of each wide portion 46 (the lower side, bottom surface 48, and / or side surface 49 of the wide portion 46 in FIGS. 5 and 6 ) is received and abuts against the plurality of receiving portions 40 provided on the base plate 20 of the semi-finished substrate 2. At this time, it is preferable that both the bottom surface 48 and the side surface 49 on the surface side of the wide portion 46 are abutting against the receiving portions 40. Note that FIG. 10 shows a state in which the surface side of each wide portion 46 is received and abuts against the receiving portions 40 of the base plate 20. By receiving and abutting the surface side of the wide portion 46 against the receiving portions 40 of the base plate 20 in this manner, a brazing material 55 is interposed between the surface side of the wide portion 46 and the receiving portions 40 of the base plate 20.

[0037] Next, while the plurality of fin members 21 held by the jig 50 are arranged in parallel on the base plate 20 of the semi-finished substrate 2 (while the plurality of fin members 21 are held by the jig 50), heating is performed in a vacuum or non-oxidizing atmosphere to melt the brazing material 55 interposed between the surface side of the wide portion 46 and the receiving portion 40 of the base plate 20. Thereafter, cooling is performed to solidify the brazing material 55, thereby brazing the surface side of the wide portion 46 to the receiving portion 40 of the base plate 20, as shown in FIG. In Examples 1 to 4 of the present application, the bottom and side surfaces of the wide portion of the fin member 21 were placed in contact with the receiving portion 40 of the base plate 20 on which the brazing material was formed, via the brazing material, and then the fin member 21 was heated to 590°C in an N2 gas atmosphere (oxygen concentration of 100 ppm or less) to melt the brazing material, and then cooled to join the fin member 21 and the receiving portion 40 via the brazing material. In this way, a heat dissipation fin 13 is formed in which a plurality of fin members 21 are integrally fixed to the base plate 20 by brazing, and the jig 50 is removed, thereby obtaining a metal-ceramic bonding substrate 1 according to an embodiment of the present invention.

[0038] In the metal-ceramic bonding substrate 1 according to the embodiment of the present invention thus manufactured, the multiple fin members 21 are attached to the base plate 20 by brazing. This prevents the base plate 20 from being pressed horizontally (in the longitudinal or transverse direction of the plate), preventing excessive loads from being applied to the ceramic plate 15 and the reinforcing member 16. As a result, cracking of the ceramic plate 15 and the reinforcing member 16 can be avoided. Furthermore, the metal-ceramic bonding substrate 1 can be obtained without melting the fin main body 45. Furthermore, by using the jig 50, the fin members 21 can be aligned and then smoothly and easily attached to the base plate 20 by brazing, thereby reducing the manufacturing cost of attaching the fin members 21. Furthermore, by forming wide portions 46 at the ends of the fin members 21 and joining the front surfaces of the wide portions 46 to the receiving portion 40 of the base plate 20, the joining area of ​​the brazing material is large, the brazing material spreads well, and the joining reliability is high.

[0039] While one example of an embodiment of the present invention has been described above, the present invention is not limited to the illustrated embodiment. For example, while Figures 1 and 2 show a base plate 20 having a laminated structure in which a reinforcing member 16 is interposed inside a metal layer 17, a base plate 20 consisting of only a metal layer 17 may also be used. Figure 12 shows an example of manufacturing a semi-finished substrate 2 having a base plate 20 (metal plate) consisting only of a metal plate for circuits, a ceramic plate 15, and a metal layer 17 (without a reinforcing member 16 inside) by the molten metal joining method. Table 2 also shows examples 5 to 8 of combinations of manufacturing conditions for the semi-finished substrate 2 in this case. That is, the semi-finished substrate 2 was produced in the same manner as in examples 1 to 4, except that the reinforcing member 16 (ceramics) was not placed in the mold. Thereafter, using the same fin member 21 and jig 50 as in examples 1 to 4, the fin member 21 could be formed (brazed) on the base plate 20 of the semi-finished substrate 2 by the same manufacturing method, and the metal-ceramic bonding substrate 1 was completed.

[0040] [Table 2] [Explanation of symbols]

[0041] 1. Metal-ceramic bonded substrate 2 Substrate semi-finished products 12 Metal circuit board 13 Heat dissipation fin 15 Ceramic plate 16 Reinforcement members 17 Metal layer 20 base plate 21 Fin member 30 Upper mold 31 Lower mold 32 Mold 33 Cavity 34 Yudo 35 Tank section 36 Lid 40 Receptor 41 (receptor) upper end 45 Fin body 46 Wide section 47 (wide part) end 48 (wide part) bottom 49 (wide part) side 50 Jig 51 Support part 52 Bar member 53 Slot section 54 Recess 55 Brazing material

Claims

1. A metal-ceramic bonding substrate in which a base plate having heat dissipation fins is bonded to one surface of a ceramic plate, the heat dissipation fins are made up of a plurality of fin members attached to the base plate, The base end of the fin member is formed with a wide portion having a trapezoidal cross section that protrudes outward from the side surface of the fin member on both sides, The base plate is formed with a plurality of receiving portions each having a trapezoidal cross-sectional shape corresponding to the cross-sectional shape of the wide portion, The metal-ceramic bonding substrate, wherein the surface side of the wide portion is brazed to the receiving portion of the base plate, and the fin member is attached to the base plate.

2. 2. The metal / ceramic bonding substrate according to claim 1, wherein the fin member is made of aluminum or an aluminum alloy.

3. 3. The metal / ceramic bonding substrate according to claim 1, wherein the material of said base plate is aluminum or an aluminum alloy.

4. 4. The metal / ceramic bonding substrate according to claim 1, wherein a metal circuit plate is formed on the other surface of said ceramic plate.

5. 5. The metal / ceramic bonding substrate according to claim 4, wherein the material of said metal circuit plate is aluminum or an aluminum alloy.

6. 6. The metal / ceramic bonding substrate according to claim 1, wherein a reinforcing member is formed inside said base plate.

7. A method for producing a metal-ceramic bonding substrate in which a base plate having heat dissipation fins is bonded to one surface of a ceramic plate, comprising: the heat dissipation fins are made up of a plurality of fin members attached to the base plate, The base end of the fin member is formed with a wide portion having a trapezoidal cross section that protrudes outward from the side surface of the fin member on both sides, The base plate is formed with a plurality of receiving portions each having a trapezoidal cross-sectional shape corresponding to the cross-sectional shape of the wide portion, The method for producing a metal-ceramic bonding substrate includes brazing the surface side of the wide portion in a state where the surface side of the wide portion is in contact with the receiving portion.

8. 8. The method for manufacturing a metal-ceramic bonding substrate according to claim 7, wherein the plurality of fin members are arranged in parallel using a jig, and then the front surfaces of the wide portions of the plurality of fin members are brought into contact with the receiving portions and brazed.

9. 9. The method for producing a metal / ceramic bonding substrate according to claim 7, wherein the fin members are made of aluminum or an aluminum alloy.

10. 10. The method for producing a metal / ceramic bonding substrate according to claim 9, wherein the fin member is an extruded material.

11. 11. The method for producing a metal / ceramic bonding substrate according to claim 7, wherein the material of the base plate is aluminum or an aluminum alloy.

12. 12. The method for producing a metal / ceramic bonding substrate according to claim 7, wherein a metal circuit plate is provided on the other surface of the ceramic plate.

13. 13. The method for producing a metal / ceramic bonding substrate according to claim 12, wherein the material of the metal circuit plate is aluminum or an aluminum alloy.

14. The method for producing a metal / ceramic bonding substrate according to any one of claims 7 to 13, wherein a reinforcing member is formed inside said base plate.

15. 15. The method for producing a metal / ceramic bonding substrate according to claim 7, wherein the ceramic plate and the base plate are bonded by a molten metal bonding method.

16. 14. The method for producing a metal / ceramic bonding substrate according to claim 12, wherein the ceramic plate and the metal circuit plate are bonded by a molten metal bonding method.

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