JP2017050539A - Manufacturing method for wiring board laminate and wiring board laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method for wiring board laminate capable of preventing short circuit via a metal plate while allowing heat dissipation thereto, and capable of dealing even with a complex circuit while ensuring sufficient strength in a non-pattern part of the metal plate, and to provide a wiring board laminate obtained by that method.SOLUTION: A metal plate 10 having a plurality of convex portions 14, an insulating layer formation material 16' having a plurality of first openings 16a at the parts corresponding to the convex portions 14 and containing a thermosetting resin, and a wiring board WB having a plurality of second openings 19a, 20a at the parts corresponding to the convex portions 14, are prepared. Said plate, material and board are laminated while being aligned, and hot pressed to form a laminate where the height of the convex portions 14 is equal to or higher than the surface of the wiring board WB or its formation material WB'. Thereafter, the insulating layer formation material 16' covering at least the convex portions 14 is removed, thus patterning the metal plate 10 of the laminate LB.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a method of manufacturing a wiring board laminate in which a metal plate having a plurality of convex portions and a wiring board are laminated and integrated, and a wiring board laminate obtained thereby, which is used for an inverter device, a voltage conversion device, and the like. This is useful as a technique for manufacturing a substrate having good heat dissipation characteristics.

  A conventional power semiconductor module includes a metal base plate for heat dissipation, a ceramic substrate laminated thereon, a power semiconductor chip (power chip such as IGBT) mounted thereon, and a resin case for storing them. And an electrode terminal disposed in the resin case on the side of the ceramic substrate.

  Further, the semiconductor chip and the ceramic substrate or these and the electrode terminal are connected by a bonding wire, and a sealing material is filled in the resin case. Thereby, insulation between the power semiconductor chip, the ceramic substrate, the metal base plate, and the electrode terminals is ensured. Further, in the power semiconductor module, the metal base plate is attached to a cooling member such as a heat sink so that heat can be dissipated.

  And there exists the technique which connects with the upper surface terminal of a semiconductor chip, and comprises a circuit using the wiring board which has a some columnar metal body with a higher heat dissipation characteristic instead of connecting with bonding wires, such as aluminum ( For example, see Patent Document 1).

  However, since heat from the semiconductor chip is mainly transferred from the ceramic substrate to the metal base plate, it is necessary to improve these heat dissipation structures to further improve the heat dissipation characteristics. At that time, if heat can be radiated directly to the metal base plate without using the ceramic substrate, the heat radiation characteristics can be greatly improved.

  However, the back side of the semiconductor element (semiconductor chip or semiconductor package) is connected to the circuit as an electrode to constitute a part of the circuit, and the back side electrodes of the plurality of semiconductor elements are connected to the same metal base plate. This must be avoided in terms of the circuit configuration. This is a barrier when using a metal base substrate that does not use a ceramic substrate.

  On the other hand, there is a technology for mounting a light emitting element such as an LED and dissipating the heat to a metal plate to form a part of a circuit by patterning the heat dissipating metal plate (for example, patent document). 2). That is, there is provided a light emitting element mounting substrate comprising two or more columnar metal bodies, two or more electrodes provided on the back side while being in conduction with the columnar metal bodies, and an insulating layer exposing the upper surface of the columnar metal bodies. Proposed.

JP 2014-154679 A JP 2011-108688 A

  However, the substrate structure described in Patent Document 2 is difficult to use as a substrate for a semiconductor module because the strength and rigidity of the substrate decrease in the non-patterned portion after the metal plate is patterned. It was. Also, with such a simple structure, it is difficult to form a circuit, and thus it cannot be used as a substrate for a semiconductor module.

  Accordingly, an object of the present invention is to provide a wiring board that can prevent a short circuit through a metal plate while enabling heat dissipation to the metal plate, has a sufficient strength at a non-patterned portion of the metal plate, and can cope with a complicated circuit. It is providing the manufacturing method of a laminated body, and the wiring board laminated body obtained by it.

The above object of the present invention can be achieved by the present invention as follows.
That is, the manufacturing method of the wiring board laminate of the present invention is as follows.
A metal plate having a plurality of convex portions, an insulating layer forming material having a plurality of first openings in portions corresponding to the convex portions and including a thermosetting resin, and a plurality of second portions in portions corresponding to the convex portions. Preparing a wiring board having an opening or a material for forming the wiring board;
The metal plate, the insulating layer forming material, and the wiring board or the forming material thereof are laminated while aligning the convex portion, the first opening, and the second opening, and by heating and pressing, the convex portion Forming a laminate having a height equal to or higher than the surface of the wiring board or a material for forming the wiring board;
Removing the insulating layer forming material covering at least the convex part;
And patterning the metal plate of the laminate.

  According to the method for manufacturing a wiring board laminate of the present invention, when a laminate is formed by heating and pressing, an insulating layer forming material such as a thermosetting resin partially flows out of the opening, and the upper surface of the convex portion or the like is formed. Cover part or all. At that time, in the obtained laminate, the height of the convex portion is the same as or higher than that of the surface of the wiring board or the like, so the insulating layer forming material covering the convex portion can be easily removed by a belt sander or the like. Thus, a structure capable of dissipating heat to the metal plate through the convex portion is obtained. Moreover, the short circuit through a metal plate can be prevented by patterning a metal plate. At that time, in addition to the insulating layer forming material, the wiring board or its forming material is laminated and integrated, so the strength in the non-patterned portion of the metal plate is sufficient, and the wiring board is laminated or its forming material is patterned later. By doing so, it becomes possible to deal with complicated circuits.

  As a result, it is possible to prevent a short circuit through the metal plate while enabling heat dissipation to the metal plate, the strength of the non-patterned portion of the metal plate is sufficient, and a method for manufacturing a wiring board laminate that can also cope with complicated circuits Can be provided.

  In the above, a mask material that has a third opening in the same portion as the second opening of the wiring board and is arranged or pasted on the wiring board or a material for forming the wiring board is prepared using the mask material. After forming the laminate, it is preferable to remove the mask material and then remove the insulating layer forming material covering the convex portions.

  When such a mask material is not used, since the height of the convex portion in the laminate is higher than the surface of the wiring board or the like, the surface around the second opening of the wiring board or the like is easily covered with a thermosetting resin or the like. It becomes difficult to remove this. As in the above configuration, the laminate is formed by heating and pressing by using a mask material that has a third opening in the same portion as the second opening and is placed or pasted on the wiring board or a material for forming the wiring board. When forming, it becomes possible to prevent the surface around the second opening of the wiring board or the like from being covered with the thermosetting resin or the like.

  Preferably, the method further includes a step of simultaneously forming the second opening and the third opening in a state where the mask material is attached to the wiring board or a material for forming the wiring board. Thereby, it is not necessary to form and align the second opening and the third opening separately, and the productivity can be further increased.

  Moreover, it is preferable that the insulating layer forming material includes a reinforcing fiber. Thereby, when forming a laminated body by heating and pressurizing, it becomes easy to control the thickness of the insulating layer and adjust the amount of the thermosetting resin or the like partially flowing out from the opening.

  Furthermore, the wiring board is preferably a multilayer wiring board having two or more wiring layers. Thereby, the wiring board laminated body which can respond also to a more complicated circuit can be manufactured.

  Further, in the present invention, in the step of patterning the metal plate, by providing a back surface side convex portion on the back surface side of the convex portion, the wiring board laminate is penetrated from the convex portion and the back surface side convex portion. It is preferable to form a penetrating metal body. Through such a process, the columnar metal bodies can be inserted into the wiring board all at once with a simple operation, alignment accuracy is not strictly required, and it can be used for columnar metal bodies of different shapes. A wiring board having a sufficiently high strength can be obtained.

  That is, conventionally, as a technique for improving heat dissipation, a method of soldering a heat dissipation terminal of a heat-generating component on a coin-shaped copper (copper inlay) is known, but a copper inlay is inserted into a through hole. Therefore, there is a problem that high accuracy is required for alignment and the insertion process becomes complicated. Moreover, since a press-fitting device for automation is used when inserting the copper inlay, the copper inlay needs to have the same shape, and there is a problem that the degree of freedom in designing the copper inlay is reduced.

  In the above, the insulating layer forming material having a plurality of first openings in the portion corresponding to the rear surface side convex portion and including a thermosetting resin, and the plurality of second openings in the portion corresponding to the rear surface side convex portion. A step of preparing a wiring board or a material for forming the wiring board, and the laminate, the insulating layer forming material, and the wiring board or the material for forming the back surface-side convex portion, the first opening, and the second opening. Forming a laminate in which the height of the convex portion on the back surface is equal to or higher than the surface of the wiring board or a material for forming the same by heating and pressing, and at least the convex on the back surface side. It is preferable that the method further includes a step of removing the insulating layer forming material covering the portion.

  By such a process, a structure having a wiring board on both sides and a through metal body penetrating them is provided, and bending deformation or the like is less likely to occur, whereby the process of removing the insulating layer forming material on both sides can be easily performed. It becomes like this.

  On the other hand, the wiring board laminate of the present invention has a metal plate having a plurality of convex portions on the front surface side and a pattern formed on the back surface side, and a plurality of second openings in portions corresponding to the convex portions. And an insulating layer interposed between the metal plate and the wiring board and containing a cured product of a thermosetting resin, and the thermosetting resin continuous from the insulating layer is a convex portion of the metal plate And at least the upper surface of the convex portion and the upper surface of the wiring board are exposed while filling the space between the first opening and the second opening.

  According to the wiring board laminate of the present invention, since the metal plate having a plurality of convex portions is provided and at least the upper surface of the convex portion is exposed, a structure capable of radiating heat to the metal plate through the convex portions is obtained. Moreover, the short circuit through a metal plate can be prevented by patterning a metal plate. In addition, since the wiring board is provided, the strength of the non-patterned portion of the metal plate is sufficient, and it is possible to deal with complicated circuits. As a result, it is possible to prevent a short circuit through the metal plate while enabling heat dissipation to the metal plate, and to provide a wiring board laminate that has sufficient strength in the non-patterned portion of the metal plate and can cope with a complicated circuit. be able to.

  In the above, the wiring board is preferably a multilayer wiring board having two or more wiring layers. Thereby, the wiring board laminated body which can respond also to a more complicated circuit can be manufactured.

  The wiring board is preferably a multilayer wiring board having a through hole for electrically connecting two or more wiring layers. Thereby, the wiring board laminated body which can respond also to a more complicated circuit can be manufactured.

  The wiring board laminate of the present invention can prevent a short circuit through the metal plate while enabling heat dissipation to the metal plate, has sufficient strength in the non-patterned portion of the metal plate, and can cope with a complicated circuit. It is useful as a substrate for mounting power semiconductor elements.

  Another wiring board laminate of the present invention includes a plurality of penetrating metal bodies, a wiring board having a plurality of second openings in portions corresponding to the penetrating metal bodies, and laminated on the wiring board. An insulating layer containing a cured product of resin, and a thermosetting resin continuous from the insulating layer fills a space between the through metal body and the second opening, and at least an upper surface of the through metal body The upper surface of the wiring board is exposed.

  Alternatively, another wiring board laminate according to the present invention includes a plurality of penetrating metal bodies, upper and lower wiring boards having a plurality of second openings in portions corresponding to the penetrating metal bodies, and the upper and lower wiring boards. And an insulating layer containing a cured product of a thermosetting resin, and a thermosetting resin continuous from the insulating layer filling at least the space between the through metal body and the second opening, The upper surface of the penetrating metal body and the upper surface of the wiring board are exposed.

  These wiring board laminates can be inserted into the wiring board all at once by a simple operation by the manufacturing method of the present invention, and the alignment accuracy is not strictly required. In addition, it is possible to obtain a wiring board that can cope with the problem and has a sufficiently high adhesion strength of the columnar metal body.

Sectional drawing which shows an example of the wiring board laminated body of this invention Top view of the wiring board laminate shown in FIG. Sectional drawing which shows an example of the manufacturing method of the wiring board laminated body of this invention Sectional drawing which shows an example of the manufacturing method of the wiring board laminated body of this invention Sectional drawing which shows the other example of the wiring board laminated body of this invention Bottom view of the wiring board laminate shown in FIG. Sectional drawing which shows the other example of the wiring board laminated body of this invention Sectional drawing which shows the other example of the wiring board laminated body of this invention Sectional drawing which shows the other example of the wiring board laminated body of this invention Sectional drawing which shows the other example of the manufacturing method of the wiring board laminated body of this invention. Sectional drawing which shows the other example of the wiring board laminated body of this invention

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows the usage state of the wiring board laminate of the present invention. The wiring board laminate of the present invention is useful as a substrate for mounting semiconductor elements, and particularly useful as a substrate for mounting power semiconductor elements. It is. Here, the semiconductor element includes a semiconductor bare chip, a chip component, and a semiconductor package, and the power semiconductor element includes semiconductor elements such as various transistors and various diodes used in an inverter device, a voltage conversion device, and the like.

  These power semiconductor element packages generally include a metal heat sink in addition to the leads. For example, the heat sink is equipotential with the cathode in a diode, and an electrode with the same potential as the heat sink is determined according to the package form. In the illustrated example, a SiC transistor (FET) in which the heat dissipation plate (electrode 32) of the semiconductor element 30 is equipotential with the drain electrode is illustrated. In this drawing, one semiconductor element 30 is shown, but another semiconductor element (Schottky barrier diode or the like) is also mounted in the other part (not shown). The circuit is formed so as to have a potential different from that of the heat sink.

  Examples of the semiconductor element 30 include bipolar power transistors, MOSFETs, IGBTs, and FWDs (free wheeling diodes). In addition to a conventional semiconductor element using Si, a semiconductor element using SiC (silicon carbide) or GaN (gallium nitride) can be used.

  In the illustrated example, the heat sink (electrode 32) of the semiconductor element 30 and the convex portion 14 are connected by the solder 35, and the three leads (electrode 31) and the wiring pattern 20 are connected by the solder 35. Yes. If any of the three leads is equipotential with the heat radiating plate (electrode 32), electrical connection to the lead is omitted and electric connection is made to the heat radiating plate (electrode 32). be able to.

  As shown in FIG. 1, the wiring board laminate of the present invention has a plurality of convex portions 14 on the front surface side (some of which are not shown), and a metal plate 10 with a pattern formed on the back side, and the convex portions 14. A wiring board WB having a plurality of second openings 19a and 20a in a portion corresponding to the above, and an insulating layer 16 interposed between the metal plate 10 and the wiring board WB and containing a cured product of a thermosetting resin. It is out. In the wiring board laminate of the present invention, the thermosetting resin continuous from the insulating layer 16 fills the space between the protrusions 14 of the metal plate 10 and the second openings 19a and 20a, and at least the protrusions 14. The upper surface of the wiring board is exposed from the insulating layer 16 and the upper surface of the wiring board is exposed. In the present embodiment, an example is shown in which the wiring board WB is a single-sided wiring board composed of a single-layer wiring pattern 20 and a rigid board 19. Here, the “rigid substrate” refers to an insulating substrate that can be used for a rigid wiring substrate.

  As shown in FIGS. 1 to 2, the wiring pattern 20 is formed with a semiconductor element 30 and is electrically connected to a lead (electrode 31) of the semiconductor element 30 through a solder 35. The patterned metal plate 10 is electrically connected to the heat radiating plate (electrode 32) of the semiconductor element 30 through the convex portion 14 and the solder 35. Another semiconductor element (not shown) is also connected to the wiring pattern 20 in the same manner, is formed in a circuit, and is electrically connected to the metal plate 10 that is patterned via the protrusions 14 and the solder 35.

  In the present invention, as shown in FIG. 1, the metal substrate 10 is patterned, and a conduction region 10 a that is electrically connected to the heat dissipation plate (electrode 32) of the semiconductor element 30 and heat dissipation of another semiconductor element (not shown). The conductive region that is electrically connected to the plate is insulated. In the present embodiment, the conductive structure 10a that is electrically connected to the electrode 32 of the semiconductor element 30 and the non-conductive area 10b that is insulated from the conductive area 10a by removing at least the periphery of the conductive area 10a are used to provide an insulating structure. An example is shown.

  A groove 10c that reaches the insulating layer 16 is provided between the conductive region 10a and the non-conductive region 10b, and the non-conductive region 10b is insulated from the conductive region 10a.

  Since the conduction region 10a is laminated and integrated with the insulating layer 16, it does not fall off even if the groove 10c is formed. At that time, the wiring board laminate is reinforced by the presence of the rigid board 19 of the wiring board WB. For this reason, the rigid substrate 19 preferably has higher rigidity and strength than the insulating layer 16.

  The groove portion 10c can be formed by a cutting device such as a router or a dicer in addition to etching, but is preferably removed by etching. The width of the groove 10c is preferably 0.05 to 2 mm.

  In the present embodiment, it is preferable that a heat sink 40 is provided on the metal substrate 10 and a heat conductive material 41 is interposed at least in the conduction region 10a, as indicated by phantom lines in FIG. Thereby, the heat of the semiconductor element 30 can be efficiently transferred to the heat sink 40 via the conduction region 10a, and the heat dissipation effect can be further enhanced.

  As the heat transfer material 41, an insulating material is used, such as a heat transfer grease such as silicone grease, or a heat transfer sheet in which a heat transfer material such as ceramic is filled in a resin having adhesiveness or adhesiveness. Is possible. The heat conductive material 41 may be provided at least in the conductive region 10a, or may be provided in the non-conductive region 10b or the entire substrate including them.

  As the heat sink 40, various types can be used according to required heat dissipation characteristics, and any of a fin type, a rib type, a post type, and the like may be used. Further, it may be combined with a fan or a heat pipe.

  Next, an example of a method for manufacturing a wiring board laminate according to the present invention will be described while touching materials to be used.

  (1) First, as shown in FIG. 3E, the metal plate 10 having a plurality of convex portions 14 on the surface side, and a plurality of first openings 16a in portions corresponding to the convex portions 14 are thermoset. An insulating layer forming material 16 ′ containing a conductive resin and a wiring board WB or a forming material WB ′ having a plurality of second openings 19a and 20a at portions corresponding to the convex portions 14 are prepared.

  For example, the metal plate 10 having the plurality of convex portions 14 is formed as follows. As shown in FIGS. 3A to 3C, the surface metal layer 4 stacked on the metal substrate 10 is selectively etched to form the convex portion 14 at a position facing the electrode 32 of the semiconductor element 30. . The surface metal layer 4 is laminated on the metal substrate 10 via another protective metal layer 2 that exhibits resistance during the etching. The protective metal layer 2 can be omitted. In this case, the convex portion 14 can be formed on the metal substrate 10 by controlling the etching amount.

  As shown in FIG. 3A, a laminate plate SP is prepared in which a metal substrate 10, a protective metal layer 2, and a surface metal layer 4 for forming a convex portion 14 are laminated. The laminated plate SP may be manufactured by any method, and for example, any of those manufactured using electrolytic plating, electroless plating, sputtering, vapor deposition, or a clad material can be used. Regarding the thickness of each layer of the laminated plate SP, for example, the thickness of the metal substrate 10 is 100 to 2000 μm, the thickness of the protective metal layer 2 is 1 to 20 μm, and the thickness of the surface metal layer 4 is 10 to 500 μm.

  The metal substrate 10 may be either a single layer or a laminated body, and any metal may be used as a constituent metal. For example, copper, copper alloy, aluminum, stainless steel, nickel, iron, other alloys, and the like can be used. Of these, copper and aluminum are preferable from the viewpoint of thermal conductivity and electrical conductivity. With the structure including the metal substrate 10 having good heat dissipation as described above, the temperature rise of the semiconductor element 30 can be prevented, so that more driving current can be flowed and efficiency can be improved.

  As the metal constituting the surface metal layer 4, copper, copper alloy, nickel, tin and the like can be usually used, and copper is particularly preferable from the viewpoint of thermal conductivity and electrical conductivity.

  As the metal constituting the protective metal layer 2, a metal different from the metal substrate 10 and the surface metal layer 4 is used, and another metal exhibiting resistance when etching these metals can be used. Specifically, when these metals are copper, another metal constituting the protective metal layer 2 is gold, silver, zinc, palladium, ruthenium, nickel, rhodium, lead-tin solder alloy, or nickel. -A gold alloy or the like is used. However, the present invention is not limited to the combination of these metals, and any combination with another metal exhibiting resistance when the metal is etched can be used. In the case where the protective metal layer 2 is not formed, the surface metal layer 4 which is another metal can be directly formed on the metal substrate 10.

  Next, as shown in FIG. 3B, the surface metal layer 4 is selectively etched using the etching resist M. Thereby, the convex part 14 is formed in the mounting position of the semiconductor element 30. The size of the convex portion 14 can be made smaller than the size of the semiconductor element 30 to be mounted. For example, the diameter of the upper surface is 1 to 10 mm. The shape of the upper surface of the convex portion 14 may be any of a quadrangle and a circle.

  As the etching resist M, a photosensitive resin, a dry film resist (photoresist), or the like can be used. In addition, when the metal substrate 10 is etched simultaneously with the surface metal layer 4, it is preferable to provide the mask material for preventing this on the lower surface of the metal substrate 10 (not shown).

  Examples of the etching method include etching methods using various etching solutions according to the types of each metal constituting the protective metal layer 2 and the surface metal layer 4. For example, when the surface metal layer 4 is copper and the protective metal layer 2 is the aforementioned metal (including a metal resist), a commercially available alkaline etching solution, ammonium persulfate, hydrogen peroxide / sulfuric acid, or the like can be used. After the etching, the etching resist M is removed.

  Next, as shown in FIGS. 3C to 3D, the exposed protective metal layer 2 is removed, but the insulating layer 16 can be formed without removing the protective metal layer 2. The protective metal layer 2 can be removed by etching. Specifically, when the surface metal layer 4 is copper and the protective metal layer 2 is the above-mentioned metal, an acid-based etching solution such as nitric acid, sulfuric acid, or cyan is commercially available for solder removal. Etc. are preferably used.

  When the protective metal layer 2 exposed in advance is removed, the surface of the metal substrate 10 is exposed from the removed portion. In order to improve the adhesion between the surface and the insulating layer 16, surface treatment such as blackening treatment and roughening treatment is performed. It is preferable to carry out.

  As shown in FIG. 3E, the insulating layer forming material 16 ′ has a plurality of first openings 16 a at portions corresponding to the convex portions 14. The first opening 16a can be formed by a drill or a punch. The size of the first opening 16 a is preferably slightly larger than the upper surface of the convex portion 14, but may be smaller than the upper surface of the convex portion 14. When the first opening 16a is made smaller than the upper surface of the convex portion 14, when the laminate LB is formed by heating and pressing, the portion covers the upper surface of the convex portion 14, but this is removed in a later step. It is possible.

  The shape of the upper surface of the convex portion 14 and the shape of the first opening 16a and the like do not necessarily match, and both may be the same shape or different shapes (the same applies to other openings).

  As the insulating layer forming material 16 ′, any material may be used as long as it contains a thermosetting resin, and any material can be used as long as it is deformed during lamination and solidified by heating or the like and has heat resistance required for the wiring board. But you can. Specific examples include various reaction curable resins such as polyimide resins, phenol resins, and epoxy resins, and composites (prepregs) of the same with glass fibers, ceramic fibers, aramid fibers, and the like.

  Further, the insulating layer forming material 16 ′ is preferably made of a material having high heat conductivity, and examples thereof include a resin containing a heat conductive filler.

  The insulating layer forming material 16 ′ is preferably composed of a thermally conductive filler that is a metal oxide and / or a metal nitride and a resin (insulating adhesive). Metal oxides and metal nitrides are preferably excellent in thermal conductivity and electrically insulating. Aluminum oxide, silicon oxide, beryllium oxide, and magnesium oxide are selected as the metal oxide, and boron nitride, silicon nitride, and aluminum nitride are selected as the metal nitride. These can be used alone or in combination of two or more. . In particular, among the metal oxides, aluminum oxide can easily obtain an insulating adhesive layer having good electrical insulation and thermal conductivity, and can be obtained at low cost. Of these materials, boron nitride is preferable because it is excellent in electrical insulation and thermal conductivity and has a low dielectric constant.

  The resin constituting the insulating layer forming material 16 ′ includes a metal oxide and / or a metal nitride, but is bonded to the metal substrate 10 (the protective metal layer 12 if present) in a cured state. And those that do not impair withstand voltage characteristics and the like are selected. As such a resin, an epoxy resin, a phenol resin, a polyimide resin, and various engineering plastics can be used singly or as a mixture of two or more, and among them, an epoxy resin is excellent in bonding strength between metals. preferable. In particular, among epoxy resins, bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, hydrogenated bisphenol A-type epoxy resins, hydrogenated, which have high fluidity and excellent mixing properties with the above metal oxides and metal nitrides. Bisphenol F type epoxy resins, triblock polymers having bisphenol A type epoxy resin structures at both ends, and triblock polymers having bisphenol F type epoxy resin structures at both ends are more preferred resins.

  As shown in FIG. 3E, the wiring board WB or the forming material WB ′ has a plurality of second openings 19 a and 20 a in a portion corresponding to the convex portion 14 of the metal plate 10. In the present embodiment, an example in which a copper-clad rigid substrate before pattern formation is used as the forming material WB ′ of the wiring substrate WB is shown. This copper-clad rigid substrate has a metal layer 20 'and a cured insulating layer 19' adhered to the metal layer 20 'and having reinforcing fibers. As the forming material WB ′ of the wired substrate WB, a copper clad laminate can be used.

  The second openings 19a and 20a can be formed by a drill or a punch. The size of the second openings 19 a and 20 a is preferably slightly larger than the upper surface of the convex portion 14, but may be smaller than the upper surface of the convex portion 14. In the case where the second openings 19a and 20a are made smaller than the upper surface of the convex portion 14, when the laminated body LB is formed by heating and pressing, the portion covers the upper surface of the convex portion 14, but this is a subsequent process. It is possible to remove.

  The copper-clad laminate usually has a semi-cured insulating layer 19 ′ adhered to the metal layer 20 ′. However, in the present invention, the insulating layer forming material 16 ′ is used to connect the wiring board WB or its forming material WB ′. Since adhesion is possible, a pre-cured insulating layer can be used. Further, a patterned metal layer may be provided on the surface of the insulating layer 19 '.

  As the material of the insulating layer 19 ', the same material as the insulating layer forming material 16' as described above can be used. As the hardened insulating layer, the same hardened material of the insulating layer forming material 16 'as described above can be used.

  Further, the metal layer 20 'may be any metal, and for example, copper, copper alloy, aluminum, stainless steel, nickel, iron, other alloys, etc. can be used. Of these, copper and aluminum are preferable from the viewpoint of thermal conductivity and electrical conductivity.

  In this embodiment, as shown in FIG. 3E, the third opening 21a is provided in the same portion as the second openings 19a and 20a, and is pasted on the forming material WB ′ of the wiring board WB. An example in which the mask material 21 is prepared and the stacked body LB is formed using the mask material 21 will be described.

  The mask material 21 may be affixed on the wiring board WB, or may be disposed only on the wiring board WB or the forming material WB '. Moreover, as the mask material 21, it is also possible to use a material that does not have the third opening 21a.

  In the present invention, it is preferable to form the second openings 19a and 20a and the third opening 21a at the same time in a state where the mask material 21 is pasted on the wiring board WB or its forming material WB ′. It is also possible to form it.

  The mask material 21 is preferably a resin film, and any of polyesters such as polyethylene terephthalate, polyolefins such as polyethylene and polypropylene, and polyamides can be used. However, polyesters such as polyethylene terephthalate are preferable from the viewpoint of heat resistance.

  When the mask material 21 is attached, it is preferable to provide an adhesive layer on the mask material 21. As the adhesive, a rubber adhesive, an acrylic adhesive, a silicone adhesive, or the like can be used. Instead of providing the pressure-sensitive adhesive layer on the mask material 21, a pressure-sensitive adhesive layer can be separately applied and formed.

  Moreover, as the mask material 21, a plate-shaped member can be used. In that case, it is preferable to arrange without attaching. As such a mask material 21, a resin plate, a metal plate, a double-sided copper-clad laminate, a single-sided copper-clad laminate, or the like can be used.

  (2) Next, as shown in FIGS. 3 (e) to 3 (f), the metal plate 10, the insulating layer forming material 19 ′, and the wiring board WB or the forming material WB ′ are connected to the protrusion 14. The first opening 16a and the second openings 19a and 20a are stacked while being aligned, and the height of the convex portion 14 is the same as the surface of the wiring board WB or the forming material WB ′ by heating and pressing. A higher laminate is formed. In the present embodiment, an example in which the stacked body LB is formed using the mask material 21 is shown.

  As a result, as shown in FIG. 3 (f), the upper surface of the convex portion 14 is covered with the insulating layer forming material 16 ′ (mainly thermosetting resin) to have the convex portion A. In addition, a part of the insulating layer forming material 16 ′ may cover the periphery of the third opening 21 a, but due to the presence of the mask material 21, the insulating layer forming material 16 is formed on the surface of the wiring board WB or the forming material WB ′. 'Can effectively prevent the adhesion. That is, even if the insulating layer forming material 16 ′ covers the periphery of the third opening 21 a of the mask material 21, the insulating layer forming material 16 ′ can be removed only by removing the mask material 21.

  For the heating and pressurization, a method of heating and pressing with a pressing surface can be adopted, and at least a concave deformation is caused between the pressing surface and the laminated body so that the convex portion A can be easily formed at a position corresponding to the convex portion 14. It is preferable to arrange an allowable sheet material. When the sheet material is not disposed, the height of the convex portion A is the same position as the upper surface of the mask material 21. Moreover, you may use the press surface which has a recessed part in the position corresponding to the convex part 14. FIG.

  As a heating press method, a heating / pressurizing apparatus (thermal laminator, heating press) or the like may be used. In this case, the atmosphere may be set to a vacuum (vacuum laminator or the like) in order to avoid air contamination. Conditions such as heating temperature and pressure may be appropriately set according to the material and thickness of the insulating layer forming material and the metal layer forming material, but the pressure is preferably 0.5 to 30 MPa.

  The sheet material may be any material that allows concave deformation at the time of heating press, such as cushion paper, rubber sheet, elastomer sheet, nonwoven fabric, woven fabric, porous sheet, foam sheet, metal foil, and composites thereof. Can be mentioned. In particular, those that can be elastically deformed, such as cushion paper, rubber sheets, elastomer sheets, foam sheets, and composites thereof, are preferable.

  (3) Next, as shown in FIG. 3G, at least the insulating layer forming material 16 ′ covering the convex portions 14 is removed. That is, the convex part A above the convex part 14 of the metal plate 10 is removed, and the upper surface of the convex part 14 is exposed. When removing the convex portion A, it is preferable to remove and flatten the metal layer 20 ′ so that the upper surface of the metal layer 20 ′ and the height of the convex portion 14 coincide with each other. However, in order to easily remove the insulating layer forming material 16 ′, it is ideal that the convex portion 14 is higher than the upper surface of the metal layer 20 ′.

  In the present embodiment, the mask material 21 is removed prior to the removal of the protrusions A. However, the mask material 21 can be removed at the same time as the insulating layer forming material 16 ′ is removed.

  As a method for removing the convex portion A, a method by grinding or polishing is preferable. A method using a grinding device having a hard rotating blade in which a plurality of hard blades made of diamond or the like are arranged in the radial direction of the rotating plate, a sander, a belt sander , A method using a grinder, a surface grinder, a hard abrasive molded article, or the like. When the grinding apparatus is used, the upper surface can be flattened by moving the hard rotary blade along the upper surface of the fixedly supported wiring board while rotating the hard rotary blade. Moreover, as a grinding | polishing method, the method of lightly grind | polishing by a belt sander, buff grinding | polishing etc. is mentioned. When the convex part A is formed in the laminated body LB like this invention, it will become easy to grind only the part and the whole planarization can be performed more reliably.

  When the formation material WB ′ of the wiring board WB is laminated and integrated as in the present embodiment, the metal layer 20 ′ is patterned as necessary. Prior to this, the exposed protrusions 14 and the metal layer 20 'can be metal-plated to form a metal-plated layer. As the metal species for metal plating, for example, copper, silver, Ni and the like are preferable. Examples of the method for forming the pattern of the metal plating layer include a panel plating method in which a pattern is formed using an etching resist, and a pattern plating method in which a pattern is formed by using a resist for pattern plating.

  The pattern formation of the metal layer 20 'can be performed as follows. For example, the wiring pattern 20 is formed by etching the metal plating layer and the metal layer 20 ′ with a predetermined pattern using an etching resist. At that time, the metal substrate 10 can also be etched at the same time to form the groove 10c.

  The removal of the etching resist may be appropriately selected according to the type of etching resist, such as removal of chemicals and removal of peeling. For example, in the case of photosensitive ink formed by screen printing, it is removed with chemicals such as alkali.

  (4) Next, as shown in FIGS. 4A to 4B, a pattern is formed on the metal plate 10 of the laminate LB. For example, by using the etching resist M to etch the metal plate 10 with a predetermined pattern, the groove 10c can be formed to form the predetermined pattern.

  Etching using the etching resist M can be performed similarly to the pattern formation of the metal layer 20 ′. In addition to etching, a pattern can be formed using a cutting device such as a router or a dicer.

(Another embodiment)
(1) In the above-described embodiment, the example of the wiring board laminate in the case where the semiconductor element is a package has been described. However, it can also be used when the semiconductor element is a chip-like semiconductor element such as a bare chip or a chip component as follows. .

  As shown in FIGS. 5 to 6, the wiring board laminate of the present invention is provided with a chip-like semiconductor element 30 having at least one electrode 32 on the bottom surface and at least one electrode 31 on the top surface. It is also possible to use it. In the illustrated example, the semiconductor element 30 includes an electrode 32 on the bottom surface and two electrodes 31 on the top surface.

  The wiring pattern 20 is formed in a circuit together with the semiconductor element 30 and is electrically connected to the electrode 31 of the semiconductor element 30 via the wire 33. Further, the patterned metal plate 10 is electrically connected to the electrode 32 of the semiconductor element 30 via the convex portion 14. The electrode 32 and the convex portion 14 are connected by a solder 35 or the like.

  In the present invention, as shown in FIG. 6, the metal substrate 10 is patterned, and the conductive region 10a that is electrically connected to the electrode 32 of the semiconductor element 30 and at least the periphery of the conductive region 10a are removed from the conductive region 10a. And an insulated non-conducting region 10b. A groove 10c that reaches the insulating layer 16 is provided between the conductive region 10a and the non-conductive region 10b, and the non-conductive region 10b is insulated from the conductive region 10a.

  In this embodiment, the electrode 31 on the upper surface of the semiconductor element 30 and the convex portion 14 are electrically connected, but the electrode on the lower surface of the semiconductor element 30 and the wiring pattern 24 of the lower wiring substrate 20 are electrically connected. May be. For example, in the case of a semiconductor element 30 such as an IGBT, the collector on the lower surface is soldered to the wiring pattern 24 of the lower wiring substrate 20 with solder 25 or the like, and the gate and emitter on the upper surface serve as two electrodes 31 of the upper wiring substrate 10. Solder joining is performed with the convex portion 14 and the solder 32 or the like. Examples of the electrical connection include solder bonding by solder 32, brazing, bonding by gold bumps, and the like.

  In the case of FWD, the cathode electrode on the lower surface is soldered to the wiring pattern 24 of the lower wiring substrate 20 by solder 25 or the like, and the anode electrode on the upper surface is soldered by the convex portion 14 of the upper wiring substrate 10 or solder 32 or the like as the electrode 31. Be joined.

  (2) In the above-described embodiment, an example in which a copper-clad laminate or the like is used as a wiring board forming material has been shown, but it is also possible to use a copper foil and an insulating layer separately. Moreover, it is also possible to use a wiring board in which the whole or a part is patterned instead of the forming material of the wiring board.

  At that time, as shown in FIG. 7, it is also possible to use a double-sided wiring board as the wiring board WB. When using a double-sided wiring board, it is preferable to have an interlayer connection structure such as a plated through hole, a metal bump, a filled via, or a plated via. Alternatively, only the lower surface may be patterned in advance, and the upper surface may be patterned after lamination. Furthermore, it is possible to use a wiring board having three layers or four layers or more.

  (3) In the above-described embodiment, the example in which the circuit is formed with the wiring pattern via the convex portion of the metal plate has been shown. However, as shown in FIG. 8, the plated through hole for interlayer connection between the metal plate 10 and the wiring pattern 20. It is also possible to provide 22.

  Such plated through holes 22 can be formed by performing metal plating after providing through holes with a drill or the like. At this time, by masking the upper and lower surfaces, it is possible to prevent the portions other than the through holes from being plated. It is also possible to provide the plated through hole 22 and the upper and lower surface plating layers without masking before forming the pattern of the metal plate 10 and to form the pattern of the metal plate 10 later.

  (4) In the above-described embodiment, an example in which a laminated body is formed using a mask material has been described. However, in the present invention, a wiring board or a material for forming the laminated body is laminated without using a mask material, and the laminated body is formed. It is also possible to form. In that case, the insulating layer forming material is coated around the second opening of the wiring board or the material for forming the wiring substrate, but this can be removed in a later step.

  (5) In the above-described embodiment, the example in which the plating layer is not provided on the upper surface of the convex portion 14 of the metal plate 10 has been described. However, in the present invention, as illustrated in FIG. 9, the upper surface of the convex portion 14 of the metal plate 10. A plating layer 23 may be provided on the substrate. Alternatively, a plating layer 23 may be provided on the upper surface of the metal layer 20 ′, and the wiring pattern 20 may be formed by etching the plating layer 23. By forming the wiring pattern 20 that is electrically connected to the convex portion 14 of the metal plate 10, it is easy to form a circuit when the semiconductor element 30 is mounted even if the conductive region 10 a of the metal plate 10 is independent from the surroundings. become.

  (6) In the above-described embodiment, only the wiring board laminate in which the semiconductor element 30 is mounted is shown, but a wiring pattern corresponding to the circuit is provided in the other part of the wiring board laminate. In addition, electronic components corresponding to the circuit are mounted.

  (7) In the above-described embodiment, in the step of forming the pattern of the metal plate, an example in which there are many portions that do not conduct to the convex portion on the back surface side of the metal plate is shown. As shown in d), in the present invention, in the step of patterning the metal plate 10, by providing the back side convex portion 15 on the back side of the convex portion 14, the convex portion 14 and the back side convex portion 15 are provided. From the above, a through metal body TM penetrating the wiring board laminate may be formed.

  In that case, as shown in FIG. 10 (c), an insulating layer forming material 16 ′ having a plurality of first openings 16a in a portion corresponding to the back surface side convex portion 15 and containing a thermosetting resin, and the back surface side A wiring board WB having a plurality of second openings 19a and 20a in a portion corresponding to the convex portion 15 or a forming material WB ′ thereof is prepared.

  Next, as shown in FIG. 10 (d), the laminated body LB, the insulating layer forming material 16 ′, the wiring board WB or the forming material WB ′ thereof, the back side convex portion 15, the first opening 16a, and the second opening 19a. , 20a are laminated while being aligned, and a laminated body is formed by heating and pressurizing so that the height of the back surface-side convex portion 15 is equal to or higher than the surface of the wiring board WB or the forming material WB ′ thereof. Further, the step of removing the insulating layer forming material 16 ′ covering at least the back side convex portion 15 can be further performed.

  By such a process, as shown in FIG. 10D, a plurality of through metal bodies TM, and upper and lower wiring boards WB having a plurality of second openings 19a and 20a in portions corresponding to the through metal bodies TM, An insulating layer 16 interposed between the upper and lower wiring boards WB and including a cured product of a thermosetting resin, and the thermosetting resin continuous from the insulating layer 16 is formed between the through metal body TM and the second opening. A wiring board laminate in which at least the upper surface of the through metal body TM and the upper surface of the wiring board are exposed while filling the space between 19a and 20a can be obtained.

  The back surface side wiring board WB or its forming material WB 'can have the same material and structure as the front surface side wiring board WB or its forming material WB', and these are as described above. In addition, the same configuration as described above can be adopted for the formation of the metal plating layer and the pattern formation on the back side.

  (8) In the embodiment of the above (7), the example in which the wiring board WB is provided also on the back surface side is shown, but only the insulating layer may be provided on the back surface side. As a result, a plurality of through metal bodies TM, a wiring board WB having a plurality of second openings 19a and 20a at portions corresponding to the through metal bodies TM, and the wiring board WB are laminated, and the thermosetting resin is cured. An insulating layer 16 containing an object, and a thermosetting resin continuous from the insulating layer 16 fills a space between the through metal body TM and the second openings 19a and 20a, and at least the through metal body TM. A wiring board laminate in which the upper surface of the wiring board and the upper surface of the wiring board WB are exposed can be obtained.

  (9) In the above-described embodiment, in the wiring board laminate, the terminal structure for connecting the wiring is not mentioned, but as shown in FIG. 11, the plated layer 23 (wiring pattern) formed with a pattern is used. The protrusions 14 that are electrically connected to each other may be provided, and the wiring 36 may be connected to the pattern portions (terminals) of the metal plate 10 existing on the back surface side of the protrusions 14 by the solder 35. Thus, by providing the terminal for connecting the wiring on the back surface side, the degree of freedom of design for component mounting can be increased.

DESCRIPTION OF SYMBOLS 10 Metal plate 14 Convex part 15 Back surface side convex part 16 Insulating layer 16 'Insulating layer forming material 16a 1st opening 19 Rigid board | substrate 19' Semi-hardened insulating layer 19a 2nd opening 20 Wiring pattern 20 'Metal layer 20a 2nd opening 21 Mask material 21a Third opening 30 Semiconductor element 31 Electrode (lead)
32 electrodes (heat sink)
35 Solder A Convex B Flat surface WB Wiring board WB 'Wiring board forming material LB Laminate TM Through metal

Claims (13)

A metal plate having a plurality of convex portions, an insulating layer forming material having a plurality of first openings in portions corresponding to the convex portions and including a thermosetting resin, and a plurality of second portions in portions corresponding to the convex portions. Preparing a wiring board having an opening or a material for forming the wiring board;
The metal plate, the insulating layer forming material, and the wiring board or the forming material thereof are laminated while aligning the convex portion, the first opening, and the second opening, and by heating and pressing, the convex portion Forming a laminate having a height equal to or higher than the surface of the wiring board or a material for forming the wiring board;
Removing the insulating layer forming material covering at least the convex part;
Forming a pattern of the metal plate of the laminated body.   Prepare a mask material having a third opening in the same portion as the second opening of the wiring board, arranged or pasted on the wiring board or a material for forming the wiring board, and using the mask material, The method for manufacturing a wiring board laminate according to claim 1, wherein after the formation, the mask material is removed, and then the insulating layer forming material covering the convex portion is removed.   The method for manufacturing a wiring board laminate according to claim 2, further comprising the step of simultaneously forming the second opening and the third opening in a state where the mask material is attached to the wiring board or a material for forming the wiring board. .   The method for manufacturing a wiring board laminate according to claim 1, wherein the insulating layer forming material includes a reinforcing fiber.   The method for manufacturing a wiring board laminate according to any one of claims 1 to 4, wherein the wiring board is a multilayer wiring board having two or more wiring layers.   In the step of forming a pattern on the metal plate, a through metal body that penetrates the wiring board laminate is formed from the convex portion and the rear surface side convex portion by providing a rear surface side convex portion on the rear surface side of the convex portion. The manufacturing method of the wiring board laminated body in any one of Claims 1-5. An insulating layer forming material having a plurality of first openings in a portion corresponding to the rear surface side convex portion and containing a thermosetting resin, and a wiring board having a plurality of second openings in a portion corresponding to the rear surface side convex portion, or A step of preparing the forming material;
The laminated body, the insulating layer forming material, and the wiring board or the forming material thereof are laminated while aligning the back side convex portion, the first opening, and the second opening, and the back surface is heated and pressed. Forming a laminate in which the height of the side projection is the same as or higher than the surface of the wiring board or the material for forming the wiring board;
Removing the insulating layer forming material covering at least the back side convex portion;
The manufacturing method of the wiring board laminated body of Claim 6 which further contains these. A metal plate having a plurality of convex portions on the front surface side and patterned on the back surface side;
A wiring board having a plurality of second openings in a portion corresponding to the convex part;
An insulating layer interposed between the metal plate and the wiring board, and including a cured product of a thermosetting resin,
The wiring in which the thermosetting resin continuous from the insulating layer fills the space between the convex portion of the metal plate and the second opening, and exposes at least the upper surface of the convex portion and the upper surface of the wiring board. Board laminate.   The wiring board laminate according to claim 8, wherein the wiring board is a multilayer wiring board having two or more wiring layers.   The wiring board laminate according to claim 9, wherein the wiring board is a multilayer wiring board having a through hole that electrically connects two or more wiring layers.   It is a board | substrate for mounting a power semiconductor element, The wiring board laminated body in any one of Claims 8-10. A plurality of penetrating metal bodies;
A wiring board having a plurality of second openings in a portion corresponding to the through metal body;
An insulating layer that is laminated on the wiring board and includes a cured product of a thermosetting resin,
A wiring board in which a thermosetting resin continuous from the insulating layer fills a space between the through metal body and the second opening, and exposes at least an upper surface of the through metal body and an upper surface of the wiring board. Laminated body. A plurality of penetrating metal bodies;
Upper and lower wiring boards having a plurality of second openings in a portion corresponding to the through metal body,
An insulating layer interposed between the upper and lower wiring boards and including a cured product of a thermosetting resin,
A wiring board in which a thermosetting resin continuous from the insulating layer fills a space between the through metal body and the second opening, and exposes at least an upper surface of the through metal body and an upper surface of the wiring board. Laminated body.

Images