Method for manufacturing bonded member and insulated circuit board, and manufacturing apparatus therefor

Abstract

To suppress positional deviation and wrinkles by appropriately joining a brazing filler metal foil to a metal plate even in a fine pattern, and to suppress the occurrence of erroneous detection in automatic visual inspection.SOLUTION: A method for manufacturing a joined member in which a metal plate (11) and a brazing material foil (12) are stacked and partially joined by a partial joining device (22), the method including an air vent step of expelling air between the metal plate and the brazing material foil stacked thereon by an air vent mechanism (32), a pressing step of planarly pressing an upper surface of the brazing material foil by a pressing mechanism (33) after the air vent step, and a partial joining step of joining the brazing material foil and the metal plate by pressing a joining jig (61) against an arbitrary position from above the brazing material foil in a state where the upper surface of the brazing material foil is pressed.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a joining member used in a circuit layer of an insulating circuit board, which is formed by partially joining a brazing foil to the surface of a metal plate, a method for manufacturing an insulating circuit board using the joining member, and an apparatus for manufacturing these. [Background technology]

[0002] Insulated circuit boards used in power modules of semiconductor products, etc., have a metal layer that forms a conductor pattern layer bonded to one side of an insulating substrate made of ceramics or the like by brazing, and electronic components such as semiconductor chips are soldered onto the metal layer. In this case, a brazing foil is placed on the metal plate that forms the metal layer, and then the metal layer is laminated and bonded to the insulating substrate.

[0003] In Patent Document 1, in order to prevent misalignment, bending, etc. of the brazing foil when brazing the metal plate to the insulating substrate, a conductive pattern member is prepared in advance by partially bonding and temporarily fixing the metal plate and the brazing foil, and this conductive pattern member is then laminated and bonded to the insulating substrate. The conductive pattern member is prepared by feeding a strip-shaped brazing foil superimposed on a strip-shaped metal plate, ultrasonically seam-welding the brazing foil to the surface of the metal plate at intervals in the feeding direction, and punching out the metal plate so that two opposing sides of the outline of the conductive pattern are positioned at the welded portions. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5664254 Summary of the Invention [Problem to be solved by the invention]

[0005] However, with the method described in Patent Document 1, when the shape of the conductor pattern becomes fine, the spacing between the welds must be narrowed, and long, thin joints must be formed at close intervals, which requires a long time to temporarily fix the brazing foil. Furthermore, for pattern shapes that do not have sides long enough in the welding direction, the welds become small, making the brazing foil more likely to become misaligned. Furthermore, when considering automated visual inspection of conductor pattern components, a problem has arisen in that, in image data captured of the brazing foil surface, slight wrinkles in the brazing foil caused by seam welding resemble the image shapes of scratches and tears that need to be detected, leading to the problem of erroneously detecting wrinkles as scratches or tears.

[0006] The present invention has been made in consideration of these circumstances, and aims to properly bond solder foil to a metal plate even with a fine pattern, thereby suppressing misalignment and wrinkles, and also suppressing the occurrence of false detections in automatic visual inspection. [Means for solving the problem]

[0007] The method for manufacturing a joining member of the present invention is a method for manufacturing a joining member formed by stacking and partially joining a metal plate and a brazing foil, and includes an air venting step for expelling air between the metal plate and the brazing foil superimposed on it, a pressing step for pressing the upper surface of the brazing foil into a flat shape after the air venting step, and a partial joining step for pressing a joining jig against any position on the brazing foil while pressing down on the upper surface of the brazing foil, thereby joining a part of the brazing foil to the metal plate.

[0008] In the present invention, after the air between the metal plate and the brazing foil superimposed thereon is expelled, the brazing foil is pressed down by its surface to be joined, which prevents the brazing foil from shifting position during joining, and also prevents wrinkles from forming around the joint because the brazing foil is in close contact with the metal plate. Since the occurrence of wrinkles is small, false detections in automatic visual inspections can be suppressed. Furthermore, if the joining jig is pin-shaped and spot-joins are performed, joining can be completed in a shorter time than when joining in a seam-like manner, and it is possible to properly join the necessary areas even in fine patterns.

[0009] In the method for manufacturing a joint member of the present invention, the air removal step is performed by pressing a squeegee from above the brazing foil superimposed on the metal plate and moving it in the surface direction of the brazing foil.

[0010] By pressing a squeegee onto the solder foil superimposed on the metal plate and moving it in the surface direction, air can be expelled between the metal plate and the solder foil, thereby preventing misalignment and wrinkles from occurring.

[0011] The method for manufacturing an insulating circuit board of the present invention includes a joining member forming step of forming the joining member by the joining member manufacturing method; a pattern punching step of simultaneously punching the metal plate and the brazing foil in the joining member into a pattern shape to form a patterned joining member in which the metal plate and a portion of the brazing foil are joined; and a planar joining step of stacking the patterned joining member on an insulating substrate with the brazing foil in contact with the joining member, and joining the metal plate to the insulating substrate while pressing it into a planar shape.

[0012] After forming a joining member by joining a portion of a brazing foil to a metal plate, a series of operations can be performed continuously: punching out a patterned joining member, and joining it to an insulating substrate. During this process, misalignment between the brazing foil and the metal plate can be prevented, and the occurrence of wrinkles in the brazing foil is also suppressed, so that the entire surface of the patterned joining member can be firmly joined to the insulating substrate.

[0013] The joining member manufacturing apparatus of the present invention includes a stage on which a brazing foil is placed in a superimposed state on a metal plate, an air vent mechanism on the stage that expels air from between the metal plate and the brazing foil to bring them into close contact, a pressing mechanism that presses the brazing foil that is in close contact with the metal plate into a flat state from above, and a partial joining mechanism that joins the brazing foil in a pressed state by the pressing mechanism to the metal plate.

[0014] In the joining member manufacturing apparatus of the present invention, the air vent mechanism includes a squeegee capable of pressing the brazing foil on the stage, and a vertical movement mechanism and a horizontal movement mechanism that move the squeegee in the vertical direction and in the surface direction of the brazing foil.

[0015] In the joint member manufacturing apparatus of the present invention, the squeegee may be bent so as to be convex forward in the direction of movement by the horizontal movement mechanism. Since the air is moved from the central portion of the brazing foil in the width direction to both sides, the air can be expelled efficiently.

[0016] The patterned joint member manufacturing apparatus of the present invention includes the joint member manufacturing apparatus, a conveying mechanism that intermittently conveys the metal plate and the brazing foil in a superimposed state over the stage of the joint member manufacturing apparatus, and a pattern punching device that punches the metal plate and the brazing foil into a pattern shape simultaneously at a position downstream in the conveying direction from the joint member manufacturing apparatus, thereby forming a patterned joint member in which the metal plate and the brazing foil are joined together.

[0017] The insulated circuit board manufacturing apparatus of the present invention includes the patterned bonding member manufacturing apparatus described above, and a planar bonding apparatus that laminates the patterned bonding member on the insulating substrate while bringing the brazing foil into contact with the insulating substrate, and bonds the metal plate to the insulating substrate while pressing it into a planar state. [Effects of the Invention]

[0018] According to the present invention, even if the pattern is fine, the brazing foil can be properly bonded to the metal plate, misalignment and wrinkles can be suppressed, and the occurrence of false detections in visual inspections can be suppressed. [Brief explanation of the drawings]

[0019] [Figure 1] 1A and 1B show a patterned bonding member according to an embodiment of the present invention, manufactured by a method for manufacturing a bonding member, in which FIG. 1A is a top view and FIG. 1B is a front view. [Figure 2] 1 is a schematic diagram showing a patterned bonding member manufacturing apparatus according to an embodiment of the present invention. [Figure 3] FIG. 3 is a perspective view showing the bonding member manufacturing apparatus in FIG. 2. [Figure 4] FIG. 2 is a top view of the joint member manufacturing apparatus. [Figure 5] 1 is a flowchart showing a method for manufacturing an insulating circuit board according to an embodiment. [Figure 6] 3A to 3C are schematic diagrams showing the operation of the bonding member manufacturing device in the order of (a) to (c). [Figure 7] 6(d) to 6(f) are schematic diagrams showing the operation of the bonded member manufacturing apparatus after FIG. 6(c). [Figure 8] 7(g) to 7(i) are schematic diagrams showing the operation of the bonded member manufacturing apparatus after FIG. 7(f). [Figure 9] 1A and 1B are front views of the metal plate and the brazing foil before and after the pattern punching process. [Figure 10] 1A and 1B show a small circuit section for explaining a partial joint, where (a) is a front view and (b) is a cross-sectional view. [Figure 11] FIG. 1 is a schematic diagram showing a planar joining device. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1 shows an insulating circuit board 1, such as a power module substrate, manufactured according to the present invention. This insulating circuit board 1 has an insulating substrate 2 made of ceramics or the like, and a circuit layer 3 bonded to the surface of this insulating substrate 2. Electronic components 4, such as semiconductor chips, are mounted on this circuit layer 3. In some cases, a heat dissipation layer 5 is formed on the back surface of the insulating substrate 2, as indicated by the two-dot chain line.

[0021] The circuit layer 3 is formed from a metal plate made of pure aluminum or an aluminum alloy, and is joined to the insulating substrate 2 using Al-Si, Al-Ge, Al-Cu, Al-Mg, Al-Mn, or Al-Si-Mg brazing foil. In the illustrated example, the circuit layer 3 comprises a plurality of small circuit portions 3A-3D arranged at intervals from one another. Some of the small circuit portions 3A-3D are the same size and shape, but the others are different sizes and shapes.

[0022] In the insulating circuit board 1 of this embodiment, the metal plate 11 and the brazing foil 12 are partially temporarily fixed together in advance to form a patterned joining member 13 that integrates them, and then the patterned joining member 13 is joined to the insulating substrate 2.

[0023] As shown in FIG. 2, the patterned bonding member manufacturing apparatus 21 for manufacturing this patterned bonding member 13 includes a bonding member manufacturing apparatus 22 for forming a partial bonding member (bonded member) 14 formed by partially temporarily fixing the metal plate 11 and the brazing foil 12, a conveying mechanism 23 for intermittently conveying the metal plate 11 and the brazing foil 12 in a superimposed state to the bonding member manufacturing apparatus 22, and a pattern punching device 24 for punching the partial bonding member 14 of the metal plate 11 and the brazing foil 12 into a pattern shape at a position downstream in the conveying direction from the bonding member manufacturing apparatus 22 to form the patterned bonding member 13. The insulating circuit board manufacturing apparatus for manufacturing the insulating circuit board 1 includes, in addition to the patterned bonding member manufacturing apparatus 21 (FIG. 2), a planar bonding apparatus 25 (FIG. 11) that laminates the patterned bonding member 13 on the insulating substrate 2 while bringing the brazing foil 12 into contact with the insulating substrate 2, and bonds the metal plate 11 to the insulating substrate 2 while pressing it into a planar shape.

[0024] As shown in Figures 3 and 4, the joint member manufacturing device 22 has a horizontal stage 31 on which the brazing foil 12 is placed in a superimposed state on the metal plate 11, an air vent mechanism 32 that expels air from between the metal plate 11 and the brazing foil 12 on the stage 31 to bring them into close contact, a pressing mechanism 33 that presses the brazing foil 12 that is in close contact with the metal plate 11 into a flat state from above, and a partial joining mechanism 34 that spot-joins a portion of the brazing foil 12 that is pressed by the pressing mechanism 33 to the metal plate 11.

[0025] The stage 31 is formed in the shape of a rectangular block, with its upper surface positioned horizontally. In this case, a number of holes are formed in the stage 31, and the metal plate 11 on the stage 31 can be sucked and fixed by vacuum suction from below. The stage 31 is raised and lowered by an elevating mechanism 28 such as an air cylinder, and is configured to move between a sucking and fixing position for the metal plate 11 and a standby position. Guide posts 35 are erected vertically on both sides of the stage 31, and the air vent mechanism 32 and the holding mechanism 33 are supported by these guide posts 35. Although not shown in FIG. 3, the stage 31 is also provided with a guide mechanism 29 for guiding its vertical movement (see FIG. 2).

[0026] The guide posts 35 are provided vertically on both sides of the rear end of the stage 31, and the upper ends of the guide posts 35 are fixed by a connecting member 36 that connects the two guide posts 35 together.

[0027] The air vent mechanism 32 has a squeegee 37 that can press the brazing material foil 12 on the stage 31, a squeegee up and down movement mechanism 38 that moves the squeegee 37 in the vertical direction, and a squeegee horizontal movement mechanism 39 that moves the squeegee 37 in the surface direction (horizontal direction) of the brazing material foil 12.

[0028] The squeegee 37 is formed in the shape of a rod with a rectangular cross section as a whole, and is provided above the stage 31 along a horizontal direction parallel to the upper surface of the stage 31, with a curved shape such that a middle portion in the longitudinal direction protrudes toward one side (upstream in the conveying direction) of the stage 31. The lower surface of the squeegee 37 is formed horizontally, and a porous cushion member 40 such as urethane sponge is affixed to the entire lower surface.

[0029] The squeegee up-down movement mechanism 38 includes a drive unit 41 formed of an air cylinder or the like fixed onto the connecting member 36, and a vertical lift rod 42 that is moved up and down by the drive unit 41. The lower end of the lift rod 42 is fixed to a horizontal frame 43 that is supported on the guide post 35 so as to be able to move up and down freely, and the squeegee 37 is supported on the frame 43 via the squeegee horizontal movement mechanism 39. The lifting rod 42 passes through a support plate portion 53 of a pressure plate 51 (to be described later) and is fixed to the frame 43 .

[0030] The squeegee horizontal movement mechanism 39 is composed of a linear actuator or the like that moves a slide block 47 along a guide rail 46, and the guide rail 46 is fixed to the front of the frame 43 along the length (horizontal direction) of the frame 43, and the slide block 47 is provided on this guide rail 46 so that it can move in the length direction. The base end of the squeegee 37 is attached to the front surface of the slide block 47 via a bracket 48, so that the squeegee 37 is provided so as to protrude above the stage 31 in a cantilevered manner. The squeegee 37 is bent so as to have a convex shape facing upstream in the conveying direction of the conveying mechanism 23 .

[0031] The squeegee 37 is moved up and down together with the frame 43 by a squeegee up and down movement mechanism 38 with its cushion member 40 facing downward, and is also moved horizontally along a guide rail 46 by a squeegee horizontal movement mechanism 39.

[0032] The pressure mechanism 33 is composed of a pressure plate 51 attached to the above-mentioned guide post 35 and a pressure plate up / down movement mechanism 52 that moves the pressure plate 51 along the up / down direction of the guide post 35 . The pressure plate 51 consists of a support plate portion 53 that is arranged to span between the guide posts 35, and a plate-shaped portion 55 that is fixed horizontally to the front end of the support plate portion 53 via a bracket 54, and the plate-shaped portion 55 is positioned horizontally above the stage 31.

[0033] The pressure plate up / down movement mechanism 52 is composed of an air cylinder or the like, similar to the squeegee up / down movement mechanism 38 described above, and the tip of a vertically extending lifting rod 57 is fixed to the support plate portion 53 of the pressure plate 51. Therefore, when the presser plate 51 is moved up and down by the presser plate up and down movement mechanism 52 , the plate-like portion 55 projecting forward of the presser plate 51 moves up and down above the stage 31 .

[0034] A cushion member 58 such as a rubber sheet made of nitrile rubber (for example, Shore hardness A50 to A90) is attached to the lower surface of the plate-like portion 55 of the pressing plate 51, which surface contacts the brazing foil 12. A plurality of through holes 59 are formed in a line throughout the plate-like portion 55.

[0035] The partial joining mechanism 34 includes a joining jig 61 consisting of a pin-shaped ultrasonic horn or the like, and a jig moving mechanism 63 that moves an arm 62 holding the joining jig 61 in the horizontal and vertical directions (only the tip of the joining jig 61 is shown by a two-dot chain line in Figure 3). This partial joining mechanism 34 is positioned on the opposite side of the holding mechanism 33 with respect to the stage 31, and when the plate-shaped portion 55 of the holding plate 51 is holding down the brazing foil 12 and the metal plate 11, a joining jig 61 presses the brazing foil 12 through a through hole 59 provided in the plate-shaped portion 55 and applies ultrasonic waves to spot-join (solid-state diffusion bonding) the brazing foil 12 to the metal plate 11, and the joining is performed by a jig moving mechanism 63 which moves the joining jig 61 horizontally and vertically, entering each through hole 59 in sequence.

[0036] The conveying mechanism 23 has a metal plate supply unit 71 that holds and supplies a long, thin, plate-shaped (strip-shaped) metal plate 11 in a reel-like form, and a brazing foil supply unit 72 that holds and supplies a long, thin, strip-shaped brazing foil 12 in a reel-like form having approximately the same width as the metal plate 11, and overlaps the brazing foil 12 fed from the brazing foil supply unit 72 on top of the metal plate 11 fed from the metal plate supply unit 71, and intermittently conveys them in this overlapping state so that they pass over the stage 31 of the joining member manufacturing device 22.

[0037] The pattern punching device 24 is a press device having an upper die 75 and a lower die 76, and punches the partial bonding member 14 sent out from the bonding member manufacturing device 22 into a pattern shape between the upper die 75 and the lower die 76 to form a pattern-shaped bonding member 13.

[0038] A conveying device 77 consisting of a receiving plate, a suction mechanism, etc. is installed below the lower die 76 of the pattern punching device 24, and the patterned joining member 13 punched out by the upper die 75 and the lower die 76 is held, aligned, and sent to the next process by the conveying device 77. This conveying device 77 conveys the patterned joining member 13, for example, from the front to the back of the paper in FIG.

[0039] A method for manufacturing the insulating circuit board 1 by manufacturing the partial bonding members 14 using the bonding member manufacturing apparatus 22 configured as described above and forming them into the patterned bonding members 13 will be described with reference to FIGS. 5, this manufacturing method includes an air evacuation step of expelling air between the metal plate 11 and the brazing foil 12 superimposed thereon, a pressing step of pressing the upper surface of the brazing foil 12 into a flat state after the air evacuation step, a partial joining step of pressing a pin-shaped joining jig 61 against the brazing foil while pressing the upper surface of the brazing foil 12 to join a portion of the brazing foil to the metal plate, a pattern punching step of simultaneously punching the partially joined metal plate 11 and brazing foil 12 into a pattern shape to form a patterned joining member 13 in which the metal plate 11 and a portion of the brazing foil 12 are joined, and a planar joining step of stacking the patterned joining member 13 on the insulating substrate 2 while the brazing foil 12 is in contact with the patterned joining member 13, and joining the metal plate 11 to the insulating substrate 2 while pressing it into a flat state. The steps will be described below in order.

[0040] [Air removal process] When the metal sheet 11 and the brazing foil 12 are supplied in a stacked state onto the stage 31 by the conveying mechanism 23, the stage 31 rises to a position (adsorption / fixing position) that supports the metal sheet 11 and fixes the metal sheet 11 by adsorption. As shown by the arrow in FIG. 6( a), the squeegee 37 descends to press down on the brazing foil 12 from above, and then moves in the planar direction above the brazing foil 12 as shown by the arrow in FIG. 6( b). In this case, the squeegee 37 waits downstream of the conveying direction relative to the stage 31, and after pressing down the brazing foil 12, it moves in the opposite direction to the conveying direction by the conveying mechanism 23, i.e., from downstream to upstream. This reduces the amount of air remaining between the joining members 14 and each joining member 14 that are produced sequentially. Moreover, the squeegee 37 is bent so as to be convex in the direction of movement when removing air, so that it can move from the center of the brazing foil 12 in the width direction to both sides, pushing aside the air, resulting in good air removal efficiency.

[0041] [Pressing process] When the squeegee 37 reaches the most upstream position as shown in Figure 6(c), the plate-shaped portion 55 of the pressing plate 51 descends as shown by the arrow, and presses down on the surface of the brazing foil 12 as shown in Figure 7(d). Most of the air between the brazing foil 12 and the metal plate 11 has been expelled in the air removal process, but this pressing process brings them into close contact with each other.

[0042] [Partial joining process] Next, the joining jig 61 enters the through-holes 59 of the plate-shaped portion 55 and spot-joins the brazing filler metal foil 12 to the metal plate 11. As shown in Figures 7(e) and (f), the joining jig 61 moves sequentially, entering the necessary through-holes 59 to press the brazing filler metal foil 12 and apply ultrasonic waves to spot-join it to the metal plate 11. For example, when partially joining an Al-Si based brazing foil having a thickness of 7 μm or more and 27 μm or less to a metal plate made of pure aluminum (4N-Al), the tip diameter of the pin-shaped portion of the joining jig 61 is formed to be 1.5 mm or more and 2.5 mm or less, and the ultrasonic waves are set to, for example, a frequency of 40 kHz, an amplitude of 4.0 μm or more and 6.7 μm or less, and a pressing force of 5 N or more and 20 N or less, thereby enabling joining without causing tears or the like in the brazing foil 12.

[0043] 9 and 10, the brazing foil 12 joined in spots to the metal plate 11 by the partial joining mechanism 34 has a plurality of spot joints 65. The spot joints 65 are formed in an appropriate number at appropriate positions as described below in accordance with the planar shape of each of the small circuit portions 3A to 3D so that the brazing foil 12 is not bent or misaligned after the pattern is punched out. In the illustrated example of the patterned joining member 13, it is made up of a plurality of small circuit portions 3A to 3D. As shown in Fig. 10, one of the small circuit portions 3C has spot joints 65 provided at the four corners of the pattern shape so that the distance between the periphery of the pattern and the outer periphery of the spot joints 65 is, for example, 0.5 mm or less. Furthermore, when the spot joints 65 are spaced apart from each other by approximately 20 mm or more on the straight line of the outer periphery, as in the case of small circuit portion 3A, additional joints are provided between the existing joints.

[0044] Until all of the spot welds 65 are formed, the plate-shaped portion 55 of the presser plate 51 presses down on the upper surface of the brazing foil 12. After all of the welds have been formed, the plate-shaped portion 55 is raised as shown by the arrow in Figure 8(g), and the squeegee 37 is moved back in a raised state as shown by the arrow in Figure 8(h), and is placed in the initial position as shown in Figure 8(i). Furthermore, after the stage 31 releases the suction of the metal plate 11, the stage 31 descends to the standby position. Thereafter, the metal plate 11 and the brazing foil 12 are transported together by a predetermined distance by the transport mechanism 23, and the next spot joining operation is carried out in the same manner as above. The joining member forming process of the present invention comprises the air removal process, the pressing process, and the partial joining process.

[0045] [Pattern punching process] The bonding member 14 transported by the intermittent transport of the transport mechanism 23 from the bonding member manufacturing device 22 to the pattern punching device 24 is punched into a pattern shape by the upper mold 75 and the lower mold 76 of the pattern punching device 24. As described above, the pattern shape is a shape in which a plurality of small circuit sections 3A to 3D are arranged, and is indicated by a two-dot chain line in Figure 9. What is indicated by a solid line on the downstream side of the transport direction in the figure is the state after the pattern shape has been punched out, with the interior of the solid line being punched out to form a through hole. The patterned joining member 13 is placed on the conveying device 77 in the state that it has been punched out, and is therefore conveyed while maintaining the arrangement of the small circuit portions 3A to 3D.

[0046] [Plane joining process] The patterned joining member 13 transported by the transport device 77 is placed on the insulating substrate 2 by a robot or the like downstream and is joined by the planar joining device 25. Before being placed in the planar joining device 25, the patterned joining member 13 is visually inspected for scratches, tears in the brazing foil 12, misalignment, and the like. Before adopting the above mechanism, false detections by automatic visual inspection occurred in over 90% of patterned joint components, but after adopting this mechanism, this rate dropped to 0%.

[0047] The planar bonding device 25 includes a pressing jig 110 shown in FIG. 11 and a heating furnace 120 for heating the laminate S of the insulating substrate 2 and the patterned bonding member 13 together with the pressing jig 110 . The pressure jig 110 comprises a base plate 111, a plurality of guide posts 112 attached vertically to the four corners of the upper surface of the base plate 111, a fixed plate 113 fixed to the upper ends of these guide posts 112, a pressure plate 114 supported by the guide posts 112 so as to be freely movable up and down between the base plate 111 and the fixed plate 113, and a spring or other biasing member 115 provided between the fixed plate 113 and the pressure plate 114 to bias the pressure plate 114 downward.

[0048] The fixing plate 113 and the pressure plate 114 are arranged parallel to the base plate 111, and a laminate S of an insulating substrate and a patterned bonding member is disposed between the base plate 111 and the pressure plate 114. In this case, a backing plate 116 made of a carbon sheet and a graphite sheet is disposed on the side of the base plate 111 and the pressing plate 114 that contacts the laminate S to ensure uniform pressure.

[0049] The patterned bonding member 13 delivered by the conveying device 77 is placed on the insulating substrate 2, and if necessary, a metal plate that will become the heat dissipation layer 5 is placed on the underside of the insulating substrate 2 to construct a laminate S. After that, backing plates 116 are placed on both sides of the laminate S, and pressure is applied in the stacking direction by a pressure jig 110. Then, the pressure jig 110 is placed in a heating furnace 120 and heated in a vacuum atmosphere, whereby the insulating circuit board 1 is formed by bonding the patterned bonding member 13 to the insulating substrate 2.

[0050] In the above series of methods for manufacturing an insulated circuit board, the air between the metal plate 11 and the brazing foil 12 is expelled, and then the metal plate 11 and the brazing foil 12 are partially bonded together, and then the metal plate 11 and the brazing foil 12 are laminated and bonded to the insulating substrate 2. This allows the brazing foil 12 to be partially bonded in close contact with the metal plate 11, preventing misalignment and wrinkles from occurring, and allowing the insulated circuit board 1 to be manufactured accurately and stably. In this case, partial joints (spot joints) 65 are formed in spots, so that the brazing foil 12 can be properly joined to the metal plate 11 even with a fine pattern, and moreover, the joining member 14 can be formed in a shorter time than with a seam-shaped joint.

[0051] The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. Although the joining jig is formed in a pin shape to perform spot joining, in the present invention, spot joining is not necessarily required, and seam joining or the like may also be used. [Explanation of symbols]

[0052] 1. Insulated circuit board 2. Insulating substrate 3 circuit layers 3A~3D small circuit section 11 Metal plate 12 Brazing foil 14 Partial joint members (joint members) 21 Patterned joint member manufacturing equipment 22 Partial joining device 23 Transport mechanism 24 Pattern punching device 25 Planar joining device 28 Lifting mechanism 31 Stages 32 Air vent mechanism 33 Presser mechanism 34 Partial joining mechanism 37 Squeegee 38 Squeegee vertical movement mechanism 39 Squeegee horizontal movement mechanism 51 Retaining plate 52 Presser plate up / down movement mechanism 55 Plate-shaped part 59 Through Hole 61 Joining jig 65 Spot joint (partial joint) 71 Metal plate supply section 72 Brazing foil supply section 75 Upper mold 76 Lower mold 110 Pressure jig 120 Furnace

Claims

1. A method for manufacturing a joined member formed by stacking and partially joining a metal plate and a brazing foil, the method comprising: an air venting step for expelling air between the metal plate and the brazing foil superimposed thereon; a pressing step for pressing an upper surface of the brazing foil into a flat shape after the air venting step; and a partial joining step for pressing a joining jig against an arbitrary position on the brazing foil while pressing down on the upper surface of the brazing foil, thereby joining the brazing foil and the metal plate.

2. 2. The method for manufacturing a joined member according to claim 1, wherein the air removal process is performed by pressing a squeegee from above the brazing foil superimposed on the metal plate and moving it in the surface direction of the brazing foil.

3. 3. A method for manufacturing an insulated circuit board, comprising: a joining member forming step of forming the joining member by the joining member manufacturing method according to claim 1; a pattern punching step of simultaneously punching the metal plate and the brazing foil in the joining member into a pattern shape to form a patterned joining member in which the metal plate and a portion of the brazing foil are joined; and a planar joining step of stacking the patterned joining member on an insulating substrate in a state in which the brazing foil is in contact with the patterned joining member, and joining the metal plate to the insulating substrate while pressing it in a planar manner.

4. A joining member manufacturing device comprising: a stage on which a brazing foil is placed in a superimposed state on a metal plate; an air vent mechanism on the stage that expels air from between the metal plate and the brazing foil to bring them into close contact; a pressing mechanism that presses the brazing foil that is in close contact with the metal plate into a flat shape from above; and a partial joining mechanism that joins the brazing foil in a pressed state by the pressing mechanism to the metal plate.

5. The joining member manufacturing apparatus according to claim 4, characterized in that the air vent mechanism includes a squeegee capable of pressing the brazing foil on the stage, and a vertical movement mechanism and a horizontal movement mechanism that move the squeegee in the vertical direction and in the surface direction of the brazing foil.

6. 6. The joined member manufacturing device according to claim 5, wherein the squeegee is bent so as to have a convex shape facing forward in the direction of movement by the horizontal movement mechanism.

7. 7. A patterned bonding member manufacturing apparatus comprising: the bonding member manufacturing apparatus according to claim 4; a conveying mechanism that intermittently conveys the metal plate and the brazing foil in a superimposed state over the stage of the bonding member manufacturing apparatus; and a pattern punching device that punches the metal plate and the brazing foil into a pattern shape simultaneously at a position downstream of the bonding member manufacturing apparatus in the conveying direction, thereby forming a patterned bonding member in which the metal plate and the brazing foil are joined together.

8. 8. An apparatus for manufacturing an insulated circuit board, comprising: the apparatus for manufacturing a patterned bonding member according to claim 7; and a planar bonding apparatus that laminates the patterned bonding member on an insulating substrate with the brazing foil in contact with the insulating substrate, and bonds the metal plate to the insulating substrate while pressing the metal plate in a planar manner.

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