JP2018037515A - Insulating substrate and manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an insulating substrate manufacturing method capable of easily performing bonding operation between a metallic layer and a ceramic insulating layer.SOLUTION: The insulating substrate manufacturing method includes: a step for temporally fixing a brazing sheet 4 to the metallic layer so as to be superposed to the metallic layer by locally applying plasticity processing to a polymer 14 obtained by polymerizing the metallic layer and the brazing sheet 4; and a step, after the temporary fixing step, for collectively bonding the metallic layer, the brazing sheet 4 and a ceramic insulating layer 6 in a laminated state by brazing.SELECTED DRAWING: Figure 8

Description

  The present invention relates to a method for manufacturing an insulating substrate on which a heat generating element such as an electronic element is mounted, and the insulating substrate.

  In the present specification and claims, the term “aluminum” is used to include both pure aluminum and an aluminum alloy unless otherwise specified, and the term “plate” is specifically indicated. Except in some cases, “foil” is used to mean.

  Further, although the vertical direction of the insulating substrate according to the present invention is not limited, in this specification and the claims, in order to facilitate understanding of the configuration of the insulating substrate, the insulating substrate on which the heat generating element is mounted. Is defined as the upper side of the insulating substrate, and the opposite side is defined as the lower side of the insulating substrate.

  For a conventional method of manufacturing an insulating substrate on which an exothermic element such as an electronic element is mounted, a wiring layer (also referred to as a circuit layer) is arranged on the insulating layer in a stacked manner on the upper side of the ceramic insulating layer, It is known to join a wiring layer and an insulating layer by brazing (for example, Patent Documents 1 and 2). It is also known that a buffer layer is disposed below the insulating layer in a stacked manner with respect to the wiring layer, and the insulating layer and the buffer layer are joined by brazing. At least the wiring layer of the wiring layer and the buffer layer is generally made of a metallic material.

  In the insulating substrate, the heat generating element is mounted on the mounting surface composed of the upper surface of the wiring layer by, for example, soldering. In order to cool the exothermic element that generates heat in accordance with the operation of the exothermic element, the insulating substrate is generally bonded onto a cooling member (including a heat radiating member).

No. 8-10202 JP 2011-66387 A (paragraph [0002])

  In the above-described conventional method for manufacturing an insulating substrate, the wiring layer and the insulating layer are joined by brazing. Therefore, when joining the wiring layer and the insulating layer, a brazing material plate (eg, brazing material) is provided between the wiring layer and the insulating layer. Foil) was placed. However, the brazing material plate has poor handling properties. Therefore, it is difficult to join the wiring layer and the insulating layer, and it is difficult to mechanize this joining work. Further, even when a brazing material plate (eg, brazing material foil) is disposed between the insulating layer and the buffer layer and the insulating layer and the buffer layer are joined by brazing, the insulating layer and the buffer layer are still used for the same reason as described above. It was difficult to perform the joining work with the machine, and it was difficult to mechanize the joining work.

  The present invention has been made in view of the above-described technical background, and an object thereof is to provide an insulating substrate manufacturing method and an insulating substrate capable of easily performing a joining operation between a metallic layer and a ceramic insulating layer. There is.

  The present invention provides the following means.

[1] A step of temporarily fixing a polymer obtained by polymerizing a metal layer and a brazing sheet to the metal layer by locally plastically processing the brazing sheet on the metal layer;
A method of manufacturing an insulating substrate, comprising: after the step of performing the temporary step, joining the metallic layer, the brazing sheet, and the ceramic insulating layer together by brazing in a laminated form.

[2] The metallic layer has a mounting surface on which the exothermic element is mounted,
The mounting surface includes a planned joining region where the exothermic element is joined and a non-joining planned region where the exothermic element is not joined,
2. The method for manufacturing an insulating substrate according to claim 1, wherein, in the temporarily fixing step, the polymer is locally plastically processed in the non-bonding scheduled region of the mounting surface of the metallic layer.

[3] After the step of temporarily fixing, the method further includes a step of flattening the plastic processing portion of the polymer so that the surface on the insulating layer side of the brazing sheet becomes flat.
3. The method for manufacturing an insulating substrate according to item 1 or 2, wherein the bonding step is performed after the planarization step.

  [4] The method for manufacturing an insulating substrate according to any one of items 1 to 3, wherein the metallic layer includes an aluminum-based composite material layer containing carbon particles.

[5] A metal layer, a brazing sheet, and a ceramic insulating layer arranged in a laminated shape are provided.
further,
A plastic working part locally formed as a temporary fixing part to the metallic layer of the brazing sheet on at least one of the metallic layer and the brazing sheet;
A first brazing portion joining the metallic layer and the brazing sheet;
An insulating substrate comprising: the brazing sheet; and a second brazing portion that joins the insulating layer.

  The present invention has the following effects.

  According to the preceding paragraph 1, since the brazing sheet is temporarily fixed to the metallic layer in the temporary fixing step, the joining operation of the metallic layer, the brazing sheet, and the insulating layer can be easily performed in the bonding step. In addition, mechanization of this joining work can be achieved.

  According to the preceding item 2, in the step of temporarily fixing, the polymer is locally plastically processed in the non-joining region of the mounting surface of the metal layer, so that the plastic processing portion of the polymer becomes the mounting surface of the metal layer. It is formed in a non-joining planned area. For this reason, when the heat generating element is bonded to the mounting surface, it is possible to avoid poor bonding of the heat generating element due to the plastic working portion.

  According to the previous item 3, in the step of flattening, the plastic working portion of the polymer is flattened so that the surface on the insulating layer side of the brazing sheet is flat, thereby brazing the brazing sheet and the insulating layer by brazing. It can be joined well.

  According to the preceding item 4, the linear expansion coefficient of the metallic layer can be reduced because the metallic layer includes the aluminum-based composite material layer containing carbon particles. Thereby, the stress generated due to the difference in linear expansion coefficient between the metallic layer and the insulating layer can be reduced.

  The insulating substrate according to the preceding item 5 exhibits at least one of the effects of the preceding items 1 to 4 when the substrate is manufactured.

FIG. 1 is a schematic plan view of a wiring layer and an insulating layer in an insulating substrate according to the first embodiment of the present invention. FIG. 2 is a schematic sectional view taken along line AA in FIG. FIG. 3 is a manufacturing process flow diagram of the insulating substrate. FIG. 4 is a schematic cross-sectional view of a polymer obtained by polymerizing a wiring layer and a brazing sheet. FIG. 5 is a schematic cross-sectional view of the polymer in a state where the polymer is locally plastically processed. FIG. 6 is a schematic cross-sectional view of a polymer in a state where a brazing sheet is temporarily fixed to a wiring layer. FIG. 7 is a schematic cross-sectional view of the polymer in a state in which the plastic processing portion of the polymer is flattened. FIG. 8 is a schematic cross-sectional view of a state before the wiring layer, the brazing sheet, the buffer layer, and the cooling member are joined. FIG. 9 is a schematic cross-sectional view of an insulating substrate according to the second embodiment of the present invention. FIG. 10 is a schematic cross-sectional view of a state before the wiring layer, the first brazing sheet, the insulating layer, the second brazing sheet, the buffer layer, the third brazing sheet, and the cooling member are joined together.

  Next, several embodiments of the present invention will be described below with reference to the drawings.

  FIGS. 1-8 is a figure explaining the insulated substrate which concerns on 1st Embodiment of this invention, and its manufacturing method.

  As shown in FIG. 2, the insulating substrate 1 according to the first embodiment includes a plurality of constituent layers that are disposed in a stacked manner in the vertical direction to constitute the insulating substrate 1. The plurality of constituent layers include a wiring layer 2, a brazing sheet 4, an insulating layer 6, and a buffer layer 8. Then, the wiring layer 2, the brazing sheet 4, the insulating layer 6 and the buffer layer 8 are joined and integrated by brazing in a state where they are arranged in this order, whereby the insulating substrate 1 is formed.

  Further, the buffer layer 8 and the cooling member 12 disposed below the buffer layer 8 are joined by brazing, whereby the insulating substrate 1 is joined on the cooling member 12. Therefore, the insulating substrate 1 of the first embodiment is provided with the cooling member 12 in detail.

  In the insulating substrate 1 of the first embodiment, the wiring layer 2 corresponds to the “aluminum-based composite material layer” of the “metallic layer” recited in the claims.

  The wiring layer 2 is also called a circuit layer and is made of an aluminum-based composite material containing carbon particles, that is, an aluminum-based composite material layer containing carbon particles. Details of the composite material will be described later.

  The wiring layer 2 has a flat mounting surface 3 formed from the upper surface thereof. At least one exothermic element (indicated by a two-dot chain line in FIG. 2) 30 is mounted on the mounting surface 3 by soldering via a solder layer (not shown). In the first embodiment, the number of exothermic elements 30 bonded to the mounting surface 3 is, for example, four.

  As shown in FIG. 1, the mounting surface 3 of the wiring layer 2 is a non-joined planned area where the four heat generating elements 30 are bonded to the four planned bonding areas 3 a, 3 a, 3 a, 3 a and the heat generating elements 30 are not bonded. 3b. Each joining planned area | region 3a is a square area | region enclosed by the dashed-two dotted line shown in FIG. The non-joining planned area 3b is composed of areas other than these planned joining areas 3a on the mounting surface 3.

  The exothermic element 30 generates heat as the exothermic element 30 operates, and includes, for example, an electronic element (including a semiconductor chip).

  As shown in FIG. 2, the brazing sheet 4 is disposed on the insulating layer 6 side with respect to the wiring layer 2, and the wiring layer 2 and the insulating layer 6 are joined to each other by brazing via the brazing sheet 4. is there.

The insulating layer 6 is made of ceramic and has electrical insulation. Specifically, the insulating layer 6 is formed of a ceramic plate such as an AlN (aluminum nitride) plate, an Al ₂ O ₃ (alumina) plate, or a Si ₃ N ₄ (silicon nitride) plate.

  The buffer layer 8 is a layer for relaxing stress such as thermal stress generated in the insulating substrate 1. In the first embodiment, the buffer layer 8 is formed of an aluminum plate. More specifically, the buffer layer 8 is formed of a high-purity aluminum plate. The purity of the high purity aluminum plate is, for example, 4N or more.

  Each of the wiring layer 2, the insulating layer 6, and the buffer layer 8 has a substantially rectangular shape in plan view (see FIG. 1). The length of one side of the insulating layer 6 is set larger than the length of one side of the wiring layer 2 and is set larger than the length of one side of the buffer layer 8.

  The cooling member 12 is for cooling the exothermic element 30, and is made of metal such as aluminum. In the first embodiment, the cooling member 12 is a heat radiating member (such as a heat sink).

  However, in the present invention, the cooling member 12 is not limited to being a heat radiating member. In addition, for example, as in the cooling member 112 of the second embodiment shown in FIG. It may be provided with a flow path 112a through which (example: cooling liquid) flows.

  Next, the configuration of the wiring layer 2 will be described below.

  As described above, the wiring layer 2 is made of an aluminum-based composite material containing carbon particles. That is, the composite material includes aluminum as a matrix and carbon particles as particles to be combined with the aluminum. Hereinafter, this composite material is also referred to as “aluminum-based carbon particle composite material”.

  The kind of composite material is not limited. Desirably, the composite material is a laminate in which a plurality of coating foils obtained by coating a carbon particle layer on an aluminum foil is laminated and integrated (such a composite material is hereinafter referred to as a “stacked sintering type”). Composites) or a mixture of aluminum particles (eg, aluminum powder) and carbon particles (eg, carbon powder) sintered (hereinafter referred to as “particle-sintered composite”). It is good to be called “material”. The sintering method is not limited. In particular, the sintering method is preferably a vacuum hot press sintering method or a discharge plasma sintering method. Preferable sintering conditions by the electric discharge plasma sintering method are as follows.

  The sintering temperature is 450 to 640 ° C., the sintering time (that is, the holding time of the sintering temperature) is 10 to 300 min, and the pressure applied to the sintered material is 1 to 40 MPa.

  The kind of aluminum as a matrix is not limited. In particular, it is desirable that aluminum has a high thermal conductivity such as high-purity aluminum.

  The kind of carbon particle is not limited. In particular, it is desirable that the carbon particles have high thermal conductivity and can be easily combined with aluminum. Specifically, the carbon particles are preferably at least one selected from the group consisting of carbon fibers, carbon nanotubes, graphene, natural graphite particles and artificial graphite particles, and further, carbon fibers, carbon nanotubes, graphene and natural graphite particles. More desirably, it is at least one selected from the group consisting of graphite particles.

  As the carbon fiber, pitch-based carbon fiber, PAN-based carbon fiber, or the like is preferably used.

  As the carbon nanotubes, single-walled carbon nanotubes, multi-walled carbon nanotubes, vapor-grown carbon fibers (including VGCF (registered trademark)) and the like are preferably used.

  As graphene, single layer graphene, multilayer graphene, or the like is preferably used.

  As natural graphite particles, scaly graphite particles and the like are preferably used.

  As the artificial graphite particles, anisotropic graphite particles, pyrolytic graphite particles and the like are preferably used.

  The size of the carbon particles is not limited. When the carbon particles are carbon fibers, short carbon fibers are preferably used, and in particular, short carbon fibers having an average fiber length of 10 μm to 2 mm are preferably used. When the carbon particles are carbon nanotubes, carbon nanotubes having an average length of 1 μm or more and 10 μm or less are particularly preferably used. When the carbon particles are natural graphite particles and artificial graphite particles, natural graphite particles and artificial graphite particles having an average particle diameter of 10 μm or more and 3 mm or less are particularly preferably used.

  Next, a method for manufacturing the insulating substrate 1 according to the first embodiment will be described below.

  As shown in FIG. 3, the method for manufacturing the insulating substrate 1 includes a temporary fixing step S1, a flattening step S2, and a joining step S3.

  As shown in FIGS. 4 to 6, the temporary fixing step S <b> 1 is performed by locally plastically processing the polymer 14 obtained by polymerizing the wiring layer 2 and the brazing sheet 4, so that the brazing sheet 4 is attached to the wiring layer 2. This is a step of temporarily fixing the polymerized state on the insulating layer 6 side.

  In the polymer 14, the brazing sheet 4 is polymerized with the wiring layer 2 in a state of being substantially in surface contact with the surface of the wiring layer 2 on the insulating layer 6 side. The surface of the wiring layer 2 on the insulating layer 6 side is the surface opposite to the mounting surface 3 of the wiring layer 2.

  As shown in FIG. 4, the brazing sheet 4 is formed by cladding a skin material 4b made of a brazing material on both surfaces in the thickness direction of the core material 4a by rolling or the like. Therefore, the brazing sheet 4 is a double-sided brazing sheet in detail.

  The kind of the core material 4a of the brazing sheet 4 is not limited. The material of the core material 4a is, for example, aluminum, and is particularly preferably an aluminum alloy (more preferably, an Al—Mn-based aluminum alloy). This is because the skin material 4b can be satisfactorily clad on the surface of the core material 4a. The thickness of the core material 4a is not limited and is, for example, 50 to 400 μm.

  The kind of brazing material of each skin material 4b of the brazing sheet 4 is not limited. The brazing material of each skin material 4b is, for example, an aluminum brazing material, and is particularly preferably an aluminum alloy brazing material such as an Al—Si—Mg based aluminum alloy. The thickness of each skin material 4b is not limited, For example, it is 10-100 micrometers.

  The thickness of the wiring layer 2 is not limited, and is usually 100 μm to 2 mm.

  The method of locally plastically processing the polymer 14 obtained by polymerizing the wiring layer 2 and the brazing sheet 4 for temporarily fixing the brazing sheet 4 to the wiring layer 2 is not limited. Desirably, as shown in FIG. 5, a press working device (caulking and fixing device) 40 including a male die 41 having a pressing convex portion 41a and a female die 42 having a concave portion 42a corresponding to the pressing convex portion 41a is provided. The brazing sheet 4 is formed on the wiring layer 2 by pressing the plastic processing scheduled portion B of the polymer 14 between the pressing convex portion 41 a of the male die 41 and the concave portion 42 a of the female die 42. A method is used in which the plastic processing scheduled portion B of the polymer 14 is plastic processed (clamped in detail) so that the wiring layer 2 is temporarily fixed in a state of being polymerized on the insulating layer 6 side.

  In FIG. 1, the cross-hatching portion attached to the mounting surface 3 of the wiring layer 2 is locally applied to the polymer 14 by plastic processing of the polymer 14 (specifically, the plastic processing scheduled portion B of the polymer 14). It is the formed plastic working part 15. As shown in FIG. 6, the brazing sheet 4 is temporarily fixed to the wiring layer 2 at the plastic processing portion 15 in a state of being polymerized on the insulating layer 6 side with respect to the wiring layer 2. Therefore, this plastic working part 15 can also be regarded as a temporary fixing part in which the brazing sheet 4 is temporarily fixed to the wiring layer 2.

  Although the place of the plastic processing planned portion B of the polymer 14 is not limited, it is particularly desirable that the planned region 3b of the mounting surface 3 of the wiring layer 2 is the non-bonding planned region 3b. That is, in the temporary fixing step S <b> 1, it is desirable that the polymer 14 is locally plastically processed in the non-joining scheduled region 3 b of the mounting surface 3 of the wiring layer 2. This is because, when the heat generating element 30 is bonded to the mounting surface 3, it is possible to avoid poor bonding of the heat generating element 30 by the plastic working portion 15. In the first embodiment, the polymer 14 is locally plastically processed in the non-bonding scheduled region 3 b of the mounting surface 3 of the wiring layer 2.

  Furthermore, it is desirable that the number of places of the plastic processing scheduled portion B of the polymer 14 is a plurality of places separated from each other as shown in FIG. The reason is that the brazing sheet 4 temporarily fixed to the wiring layer 2 can be prevented from rotating relative to the wiring layer 2 with the plastic working portion 15 as the rotation center.

  Therefore, in the temporary fixing step S1, as shown in FIG. 1, the polymer 14 may be locally plastically processed at a plurality of locations spaced apart from each other in the non-joined planned region 3b of the mounting surface 3 of the wiring layer 2. Particularly desirable. In the first embodiment, the polymer 14 is locally plastically processed at two locations that are spaced apart from each other in the non-bonding scheduled region 3 b of the mounting surface 3 of the wiring layer 2.

  In the plastic working method described above, the direction in which the pressing protrusion 41a of the male die 41 presses the polymer 14 is not limited. In particular, as shown in FIG. 5, it is desirable that the pressing convex portion 41 a be in the direction in which the polymer 14 moves from the wiring layer 2 side to the brazing sheet 4 side (the direction of arrow C). When the pressing direction of the pressing convex portion 41a to the polymer 14 is the desired direction C, as shown in FIG. 6, in the state after the plastic processing portion B of the polymer 14 is plastic processed, Concave portions 3c are locally formed in the mounting surface 3 of the wiring layer 2 in the plastic processing portion 15 (more specifically, the non-joining scheduled region 3b of the mounting surface 3), and the brazing sheet 4 in the plastic processing portion 15 of the polymer 14 is formed. Convex portions 5a are locally formed on the surface 5 on the insulating layer 6 side. In other words, the concave portion 3c is formed on the mounting surface 3 of the wiring layer 2 (more specifically, the non-bonding scheduled region 3b of the mounting surface 3), and the convex portion 5a is locally formed on the surface 5 of the brazing sheet 4 on the insulating layer 6 side. Thus, the plastic processing scheduled portion B of the polymer 14 is locally plastic processed.

  In the flattening step S2, as shown in FIG. 7, after the temporary fixing step S1, the plastic processed portion 15 of the polymer 14 is flattened so that the surface 5 on the insulating layer 6 side of the brazing sheet 4 is flat. This is the process of chemical processing.

  As the flattening process, the surface 5 is formed into a flat shape by hitting a convex part 5a locally formed on the surface 5 on the insulating layer 6 side of the brazing sheet 4 in the plastic processed part 15 of the polymer 14. Processing is preferably applicable. An arrow “D” in FIG. 7 indicates a hitting direction by the hitting process.

  In the first embodiment, the hitting process is applied as the flattening process. And the convex part 5a formed locally on the surface 5 by the side of the insulating layer 6 of the brazing sheet 4 in the plastic processing part 15 of the polymer 14 by flattening the plastic processing part 15 of the polymer 14 is flat. The surface 5 is flattened by being plastically crushed at the same time, and at the same time, locally on the mounting surface 3 of the wiring layer 2 in the plastic processing portion 15 of the polymer 14 (specifically, the non-bonding scheduled region 3b of the mounting surface 3). Thus, the mounting surface 3 is substantially flattened by plastic deformation so that the concave portion 3c formed is shallow.

  As shown in FIG. 8, the bonding step S3 is performed by brazing the wiring layer 2, the brazing sheet 4, the insulating layer 6, the buffer layer 8, and the cooling member 12 in a lump after the flattening step S2. It is a process of joining and integrating.

  In a state before these (2, 6, 7, 12) are joined and integrated, as shown in the figure, the brazing sheet 4 is temporarily put on the wiring layer 2 in a state of being polymerized on the insulating layer 6 side with respect to the wiring layer 2. It is fixed.

  A brazing filler metal layer 8 a is clad by rolling or the like on both surfaces in the thickness direction of the buffer layer 8, whereby a brazing filler metal layer 8 a is formed on both surfaces of the buffer layer 8.

  The brazing material layer 8a formed on the surface of the buffer layer 8 on the insulating layer 6 side is for joining the insulating layer 6 and the buffer layer 8 by brazing. The brazing material layer 8a formed on the surface of the buffer layer 8 on the cooling member 12 side is for joining the buffer layer 8 and the cooling member 12 by brazing. The type of brazing material for each brazing material layer 8a is not limited. For example, the brazing material of each brazing material layer 8a is an aluminum brazing material, specifically, the brazing material of the same kind as the brazing material of the skin material 4b of the brazing sheet 4 described above.

  In the joining step S3, the wiring layer 2, the brazing sheet 4, the insulating layer 6, the buffer layer 8, and the cooling member 12 temporarily fixed to the wiring layer 2 are arranged in this order. These are joined and integrated together by brazing under predetermined brazing conditions.

  The brazing conditions are not limited. For example, the brazing temperature is 580 to 630 ° C., the brazing time (that is, the brazing temperature holding time) is 3 to 60 min, and the brazing atmosphere is a vacuum or a non-oxidizing gas atmosphere (Example: Argon gas atmosphere, nitrogen gas atmosphere).

  By sequentially performing the temporary fixing step S1, the flattening step S2, and the joining step S3 described above, the insulating substrate 1 of the first embodiment (specifically, the insulating substrate 1 with the cooling member 12) is obtained.

  Therefore, as shown in FIG. 2, the insulating substrate 1 of the first embodiment includes a wiring layer 2, a brazing sheet 4, an insulating layer 6, a buffer layer 8, and a cooling member 12 that are arranged in a stacked manner. Furthermore, the plastic processing part 15 locally formed as a temporary fixing part to the wiring layer 2 of the brazing sheet 4 and the wiring layer 2 and the brazing sheet 4 are joined to the polymer 14 of the wiring layer 2 and the brazing sheet 4. The first brazing part 21, the second brazing part 22 in which the brazing sheet 4 and the insulating layer 6 are joined, the third brazing part 23 in which the insulating layer 6 and the buffer layer 8 are joined, the buffer layer 8 and the cooling And a fourth brazing part 24 to which the member 12 is joined.

  According to the manufacturing method of the insulating substrate 1 of the first embodiment, the brazing sheet 4 is temporarily fixed to the wiring layer 2 in a state of being polymerized on the insulating layer 6 side with respect to the wiring layer 2 in the temporary fixing step S1, In the bonding step S3, the wiring layer 2, the brazing sheet 4, the insulating layer 6, the buffer layer 8, and the cooling member 12 can be easily arranged in a laminated form. Therefore, the joining operation for joining them can be easily performed, and the joining operation can be mechanized.

  Further, in the flattening step S2, the plastic working portion 15 of the polymer 14 is flattened (tapped) so that the surface 5 on the insulating layer 6 side of the brazing sheet 4 is flattened. In the state where the insulating layer 6 is laminated, the gap between the brazing sheet 4 and the insulating layer 6 can be reduced. Thereby, the brazing sheet 4 and the insulating layer 6 can be favorably joined by brazing.

  Moreover, since the wiring layer 2 is made of an aluminum-based carbon particle composite material, the linear expansion coefficient of the wiring layer 2 can be reduced. Thereby, the stress generated due to the difference in linear expansion coefficient between the wiring layer 2 and the insulating layer 6 is reduced. Therefore, the insulating substrate 1 has high bonding reliability with respect to the cooling / heating cycle load.

  In the insulating substrate 1 of the first embodiment, the buffer layer 8 is formed of an aluminum plate. However, in the insulating substrate according to the present invention, the buffer layer 8 is made of, for example, an aluminum-based carbon particle composite material. May be.

  9 and 10 are diagrams for explaining an insulating substrate 101 and a method for manufacturing the same according to the second embodiment of the present invention. In the figure, elements having the same action as the elements of the insulating substrate 1 of the first embodiment are given reference numerals obtained by adding 100 to the reference numerals. The insulating substrate 101 and the manufacturing method thereof according to the second embodiment will be described below with a focus on differences from the insulating substrate 1 according to the first embodiment and the manufacturing method thereof.

  In the insulating substrate 101 of the second embodiment, each of the wiring layer 102 and the buffer layer 108 corresponds to a “metallic layer” recited in the claims.

  The insulating substrate 101 of the second embodiment includes a wiring layer 102, a first brazing sheet 104, an insulating layer 106, a second brazing sheet 107, a buffer layer 108, a third brazing sheet 109, and a cooling member 112. These (102, 104, 106, 107, 108, 109, 112) are joined and integrated by brazing in a state where they are arranged in this order, whereby the insulating substrate 101 (more specifically, a cooling member) An insulating substrate 101 with 112 is formed.

  The wiring layer 102 is made of aluminum, and more specifically, is formed of a high-purity aluminum plate. The purity of the aluminum plate is, for example, 4N.

  The first brazing sheet 104 is disposed on the insulating layer 106 side with respect to the wiring layer 102, and the wiring layer 102 and the insulating layer 106 are joined to each other by brazing via the first brazing sheet 104.

  The buffer layer 108 is made of aluminum, and more specifically, is formed of a high-purity aluminum plate. The purity of the aluminum plate is, for example, 4N.

  The second brazing sheet 107 is disposed on the insulating layer 106 side with respect to the buffer layer 108, and the insulating layer 106 and the buffer layer 108 are joined to each other by brazing via the second brazing sheet 107.

  The third brazing sheet 109 is disposed on the cooling member 112 side with respect to the buffer layer 108, and the buffer layer 108 and the cooling member 112 are joined to each other by brazing via the third brazing sheet 109.

  The cooling member 112 is provided with a flow path 112a through which a cooling fluid (eg, a cooling liquid) flows.

  The first to third brazing sheets 104, 107, 109 are each formed by cladding a brazing material made of brazing material on the upper and lower surfaces of the core material by rolling or the like. That is, each of the first to third brazing sheets 104, 107, and 109 is a double-sided brazing sheet in detail, and has the same configuration as the brazing sheet 4 of the first embodiment, for example.

  A method for manufacturing the insulating substrate 101 according to the second embodiment will be described below with reference to FIG.

  In the temporary fixing step S1, the first polymer 114 obtained by polymerizing the wiring layer 102 and the first brazing sheet 104 is locally plastically processed at at least one location in the non-joined region of the mounting surface 103 of the wiring layer 102. Then, the first brazing sheet 104 is temporarily fixed to the wiring layer 102 in a state of being superimposed on the insulating layer 106 side with respect to the wiring layer 102.

  Further, the second polymer 117 obtained by polymerizing the second brazing sheet 107, the buffer layer 108, and the third brazing sheet 109 in the temporary fixing step S1 is locally plastically processed at at least one location of the second polymer 117. Thus, the second brazing sheet 107 is temporarily fixed to the buffer layer 108 in a state of being polymerized on the insulating layer 106 side with respect to the buffer layer 108, and at the same time, the third brazing sheet 109 is placed on the buffer layer 108 on the cooling member 112 side. Temporarily fix in a polymerized state.

  Next, in the flattening step S2, the first plastic working portion (first temporary fixing portion) 115 of the first polymer 114 is flattened so that the surface 105 on the insulating layer 106 side of the first brazing sheet 104 becomes flat. Processing (striking). Further, in the flattening step S2, the second plastic working portion (second temporary fixing portion) 118 of the second polymer 117 is flattened so that the surface 110 on the insulating layer 106 side of the second brazing sheet 107 becomes flat. Processing (striking).

  Note that the reference numeral “111 c” in FIG. 10 is a concave portion 111 c locally formed on the surface 111 on the cooling member 112 side of the third brazing sheet 109 in the second plastic working portion 118 of the second polymer 117. The concave portion 111c is plastically deformed so that the depth of the concave portion 111c is reduced by flattening (striking) the second plastic working portion 118 of the second polymer 117 in the flattening step S2. Thus, the surface 111 is substantially flattened.

  Thereafter, in the bonding step S3, the wiring layer 102, the first brazing sheet 104 temporarily fixed to the wiring layer 102, the insulating layer 106, the second brazing sheet 107 temporarily fixed to the buffer layer 108, and the buffer layer 108 Then, the third brazing sheet 109 temporarily fixed to the buffer layer 108 and the cooling member 112 are arranged in this order. These are joined and integrated together by brazing. Thereby, the insulating substrate 101 of the second embodiment shown in FIG. 9 is obtained.

  Therefore, the insulating substrate 101 of the second embodiment includes the wiring layer 102, the first brazing sheet 104, the insulating layer 106, the second brazing sheet 107, the buffer layer 108, and the third brazing sheet 109, which are arranged in a stacked manner. The cooling member 112 is provided, and the first polymer 114 of the wiring layer 102 and the first brazing sheet 104 is locally formed as a first temporary fixing portion to the wiring layer 102 of the first brazing sheet 104. A first plastic working part 115; a first brazing part 121 in which the wiring layer 102 and the first brazing sheet 104 are joined; a second brazing part 122 in which the first brazing sheet 104 and the insulating layer 106 are joined; The second and third brazing sheets 107, the buffer layer 108, and the third brazing sheet 109 are added to the second polymer 117. A second plastic working part 118 locally formed as a second temporary fixing part of the easing sheets 107 and 109 to the buffer layer 108, a third brazing part 125 joining the insulating layer 106 and the second brazing sheet 107, The fourth brazing part 126 in which the second brazing sheet 107 and the buffer layer 108 are joined, the fifth brazing part 127 in which the buffer layer 108 and the third brazing sheet 109 are joined, the third brazing sheet 109 and the cooling member 112 are provided. And a sixth brazed portion 128 joined together.

  According to the method for manufacturing the insulating substrate 101 of the second embodiment, the first brazing sheet 104 is temporarily fixed to the wiring layer 102 in a state of being superimposed on the insulating layer 106 side with respect to the wiring layer 102. 107 is temporarily fixed to the buffer layer 108 in a state of being polymerized on the insulating layer 106 side with respect to the buffer layer 108, and the third brazing sheet 109 is in a state of being polymerized on the buffer layer 108 on the cooling member 112 side with respect to the buffer layer 108. Temporarily fixed. Accordingly, in the bonding step S3, the wiring layer 102, the first brazing sheet 104, the insulating layer 106, the second brazing sheet 107, the buffer layer 108, the third brazing sheet 109, and the cooling member 112 can be easily arranged in a laminated form. . Thereby, the joining operation | work which joins these can be performed still more easily, and mechanization of this joining operation can be achieved reliably.

  In the insulating substrate 101 of the second embodiment, the buffer layer 108 is formed of an aluminum plate. However, in the insulating substrate according to the present invention, the buffer layer 108 is made of, for example, an aluminum-based carbon particle composite material. It may be.

  Although several embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention.

  The insulating substrate and the manufacturing method thereof according to the present invention are applied to the technical matter applied to the insulating substrate and the manufacturing method of the first embodiment, and the insulating substrate and the manufacturing method of the second embodiment. Two or more technical matters may be provided.

  Further, the metal layer of the insulating substrate according to the present invention may be composed of only an aluminum-based carbon particle composite material layer like the wiring layer 2 of the insulating substrate 1 of the first embodiment. The aluminum-based carbon particle composite material layer and one or more metallic layers may be polymerized.

  Next, specific examples of the present invention are shown below. However, the present invention is not limited to the following examples.

<Example 1>
In Example 1, the insulating substrate 1 according to the first embodiment shown in FIGS. 1 to 8 was manufactured by the following manufacturing method.

  The wiring layer 2, the brazing sheet 4, the insulating layer 6, the buffer layer 8, and the cooling member 12 were prepared.

  The wiring layer 2 is made of a plate-like aluminum-based carbon particle composite material, and more specifically, the above-described laminated sintered composite material. The carbon particle content (Vf) in the composite material was 15% by mass. The thickness of the wiring layer 2 was 400 μm.

  The brazing sheet 4 was a double-sided aluminum brazing sheet having a thickness of 200 μm and a cladding rate of 12%. The material of the core material 4a of the brazing sheet 4 was aluminum, and the brazing material of each skin material 4b of the brazing sheet 4 was an aluminum alloy brazing material.

  The insulating layer 6 was formed of an AlN plate as a ceramic plate. The thickness of the insulating layer 6 was 0.63 mm.

  The buffer layer 8 was formed of a high purity aluminum plate having a purity of 4N. The thickness of the buffer layer 8 was 1.6 mm. Furthermore, the brazing filler metal layer 8a was clad by rolling on both surfaces of the buffer layer 8 in the thickness direction. The brazing material of each brazing material layer 8a was an aluminum alloy brazing material. Each brazing material layer 8a had a thickness of 50 μm.

  The cooling member 12 was an aluminum heat sink.

  Subsequently, the polymer 14 of the wiring layer 2 and the brazing sheet 4 was formed by polymerizing the brazing sheet 4 on the insulating layer 6 side with respect to the wiring layer 2 and the wiring layer 2. Then, the polymer 14 is locally plastically processed by a press working device (caulking and fixing device) 40 to temporarily fix the brazing sheet 4 on the wiring layer 2 in a state of being polymerized on the insulating layer 6 side with respect to the wiring layer 2. .

  Then, the plastic working portion (temporary fixing portion) 15 of the polymer 14 was beaten with a hammer as a hitting tool so that the surface 5 on the insulating layer 6 side of the brazing sheet 4 was flat.

  Thereafter, the wiring layer 2, the brazing sheet 4, the insulating layer 6, the buffer layer 8, and the cooling member 12 temporarily fixed to the wiring layer 2 were arranged in this order. These were joined and integrated together by vacuum brazing. The brazing conditions applied at this time are a brazing temperature of 600 ° C. and a brazing time of 20 minutes.

  The insulating substrate 1 was obtained by the above method. In the obtained insulating substrate 1, the bonding state between the wiring layer 2 and the brazing sheet 4 was good, and the bonding state between the brazing sheet 4 and the insulating layer 6 was good.

<Example 2>
In Example 2, the insulating substrate 101 of the second embodiment described above shown in FIGS. 9 and 10 was manufactured by the following manufacturing method.

  Prepare plate-like wiring layer material, plate-like first brazing sheet material, insulating layer 106, plate-like second brazing sheet material, plate-like buffer layer material, plate-like third brazing sheet material, and cooling member 112 did.

  The wiring layer material was formed of a high purity aluminum plate. The thickness of the wiring layer material was 400 μm.

  The first brazing sheet material was a double-sided aluminum brazing sheet having a thickness of 200 μm and a cladding rate of 12%. The core material of the first brazing sheet material was aluminum, and the brazing material of each skin material of the first brazing sheet material was an aluminum alloy brazing material.

  The insulating layer 106 was formed of an AlN plate as a ceramic plate. The thickness of the insulating layer 106 was 0.63 mm.

  The second and third brazing sheet materials were the same as the first brazing sheet materials, respectively.

  The buffer layer material was formed of a high purity aluminum plate having a purity of 4N. The thickness of the buffer layer material was 1.2 mm.

  The cooling member 112 is made of aluminum, and has a flow path 112a through which a coolant flows.

  Next, the first polymer material of both materials was formed by polymerizing the first brazing sheet material on the insulating layer 6 side with respect to the wiring layer material and the wiring layer material. Then, the first polymer material is locally plastically processed by a press working device (caulking and fixing device) so that the first brazing sheet material is polymerized on the wiring layer material on the insulating layer 106 side with respect to the wiring layer material. Temporarily fixed.

  Then, the 1st polymer 114 of the wiring layer 102 and the 1st brazing sheet 104 was obtained by punching a 1st polymer raw material with a punching apparatus. In the first polymer 114, the first brazing sheet 104 is temporarily fixed to the wiring layer 102 in a state of being polymerized on the insulating layer 106 side with respect to the wiring layer 102.

  Then, the first plastic working portion (first temporary fixing portion) 115 of the first polymer 114 is hit with a hammer as a hitting tool so that the surface 105 on the insulating layer 106 side of the first brazing sheet 104 becomes flat. processed.

  Moreover, the 2nd polymer material of these materials was formed by superposing | polymerizing the 2nd brazing sheet material, the buffer layer material, and the 3rd brazing sheet material. Then, the second polymer material is locally plastically processed by a press working device (caulking and fixing device) 40, whereby the second brazing sheet material is polymerized on the insulating layer 106 side with respect to the buffer layer material. At the same time, the third brazing sheet material was temporarily fixed to the buffer layer material in a state of being polymerized on the cooling member 112 side with respect to the buffer layer material.

  Then, the 2nd polymer 117 of the 2nd brazing sheet 107, the buffer layer 108, and the 3rd brazing sheet 109 was obtained by carrying out the punching process of the 2nd polymer material with a punching device. In the second polymer 117, the second brazing sheet 107 is temporarily fixed to the buffer layer 108 in a state of being polymerized on the insulating layer 106 side with respect to the buffer layer 108, and the third brazing sheet 109 is fixed to the buffer layer 108 on the buffer layer 108. On the other hand, it is temporarily fixed in a superposed state on the cooling member 112 side.

  Then, the second plastic working portion (second temporary fixing portion) 118 of the second polymer 117 is hit with a hammer as a hitting tool so that the surface 110 on the insulating layer 106 side of the second brazing sheet 107 becomes flat. processed.

  Thereafter, the wiring layer 102, the first brazing sheet 104 temporarily fixed to the wiring layer 102, the insulating layer 106, the second brazing sheet 107 temporarily fixed to the buffer layer 108, the buffer layer 108, and the buffer layer 108 The third brazing sheet 109 and the cooling member 112 temporarily fixed to each other were arranged in this order. These were joined and integrated together by vacuum brazing. The brazing conditions applied at this time are a brazing temperature of 600 ° C. and a brazing time of 20 minutes.

  The insulating substrate 101 was obtained by the above method. In the obtained insulating substrate 101, the bonding state of the wiring layer 102 and the first brazing sheet 104, the bonding state of the first brazing sheet 104 and the insulating layer 106, the bonding state of the insulating layer 106 and the second brazing sheet 107, and the second brazing. The joined state between the sheet 107 and the buffer layer 108, the joined state between the buffer layer 108 and the third brazing sheet 109, and the joined state between the third brazing sheet 109 and the cooling member 112 were good.

  INDUSTRIAL APPLICABILITY The present invention can be used for an insulating substrate manufacturing method and an insulating substrate on which a heat generating element such as an electronic element is mounted.

1: Insulating substrate 2: Wiring layer (aluminum-based composite material layer)
3: Mounting surface 4: Brazing sheet 5: Surface on the insulating layer side of the brazing sheet 6: Insulating layer 8: Buffer layer 12: Cooling member 14: Polymer 15: Plastic working part (temporary fixing part)

Claims (5)

Temporarily fixing the brazing sheet in a polymerized state with respect to the metallic layer by locally plastically processing a polymer obtained by polymerizing the metallic layer and the brazing sheet;
After the step of temporarily fixing, a method of manufacturing an insulating substrate, including a step of collectively joining the metallic layer, the brazing sheet, and the ceramic insulating layer by brazing in a laminated form. The metallic layer has a mounting surface on which a heat generating element is mounted,
The mounting surface includes a planned joining region where the exothermic element is joined and a non-joining planned region where the exothermic element is not joined,
The method for manufacturing an insulating substrate according to claim 1, wherein, in the temporarily fixing step, the polymer is locally plastically processed in the non-bonding scheduled region of the mounting surface of the metallic layer. After the step of temporarily fixing, the method further includes a step of flattening the plastic processing portion of the polymer so that the surface on the insulating layer side of the brazing sheet is flat.
The method for manufacturing an insulating substrate according to claim 1, wherein the bonding step is performed after the flattening step.   The said metallic layer is a manufacturing method of the insulated substrate in any one of Claims 1-3 containing the aluminum group composite material layer containing a carbon particle. With a metal layer, a brazing sheet, and a ceramic insulating layer arranged in a laminated manner,
further,
A plastic working part locally formed as a temporary fixing part to the metallic layer of the brazing sheet on at least one of the metallic layer and the brazing sheet;
A first brazing portion joining the metallic layer and the brazing sheet;
An insulating substrate comprising: the brazing sheet; and a second brazing portion that joins the insulating layer.

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