WO2016002804A1

WO2016002804A1 - Joined body manufacturing method, multilayer joined body manufacturing method, power-module substrate manufacturing method, heat sink equipped power-module substrate manufacturing method, and laminated body manufacturing device

Info

Publication number: WO2016002804A1
Application number: PCT/JP2015/068885
Authority: WO
Inventors: 智哉大開; 宗太郎大井; 仁人西川
Original assignee: 三菱マテリアル株式会社
Priority date: 2014-07-02
Filing date: 2015-06-30
Publication date: 2016-01-07

Abstract

[Problem] To provide a joined body manufacturing method that, when joining metal plates to each other and metal plates to ceramic plates, can prevent offset between the joining surfaces of each member, and that can efficiently manufacture these joined bodies, and to provide a power-module substrate manufacturing method in which the joined body manufacturing method is applied to a power-module substrate. [Solution] In the present invention, the following are included: a laminating step for forming a laminated body (80) in which either a copper circuit substrate (first member) (30) or a ceramic substrate (second member) (20) is coated beforehand with a temporary fixing material (40) the main ingredient of which is a saturated fatty acid, the copper circuit substrate (30) and the ceramic substrate (20) are laminated and positioned using the temporary fixing material (40) which has been melted, and by cooling the temporary fixing material (40) the laminated copper substrate (30) and ceramic substrate (20) are temporarily fixed; and a joining step for forming a joined body in which the copper circuit substrate (30) and the ceramic substrate (20) are joined by pressurizing the laminated body (80) in the lamination direction and then heating the same.

Description

Manufacturing method of bonded body, manufacturing method of multilayer bonded body, manufacturing method of power module substrate, manufacturing method of power module substrate with heat sink, and manufacturing apparatus of laminated body

The present invention relates to a method for manufacturing a laminate comprising a plurality of members used for manufacturing a power module substrate for a semiconductor device that controls a large current and a high voltage, a method for manufacturing a power module substrate, and a laminate manufacturing apparatus. About.

The present application is filed in Japan by Japanese Patent Application No. 2014-136646 filed on July 2, 2014, Japanese Patent Application No. 2014-235949 filed on November 20, 2014, and June 30, 2015. Claiming priority based on Japanese Patent Application No. 2015-130973, the contents of which are incorporated herein by reference.

Conventionally, as a power module substrate, a circuit board is bonded to one surface of a ceramic substrate in a laminated state, and a heat sink is bonded to the other surface in a stacked state. This power module substrate is provided as a power module by soldering an electronic component such as a semiconductor chip (power element) on a circuit board and bonding a heat sink to the heat sink.

In such a power module substrate, for example, there is a technique described in Patent Document 1 or 2 as a method for joining a ceramic substrate to a ceramic substrate in a laminated state.

Patent Document 1 discloses a method for manufacturing a power module substrate including an insulating layer and a circuit layer formed on one surface of the insulating layer. The power module substrate manufacturing method includes a circuit layer forming step of forming a circuit layer by laminating a copper layer on the aluminum layer after disposing an aluminum layer on one surface of the insulating layer, Solid phase diffusion bonding is performed by heating and holding an aluminum layer and a copper layer under a load.

In Patent Document 2, a brazing material foil is pasted on one surface of a metal flat plate via a resin coating layer (containing octanediol as an organic resin), and a superposition of these metal flat plate and the brazing material foil is a circuit layer. The circuit layer and the ceramic flat plate are laminated and bonded via the brazing material foil by punching and molding the outer shape of the brazing material foil onto the ceramic flat plate.

JP 2013-229545 A JP 2010-10561 A

In the method for manufacturing a power module substrate described in Patent Document 1, a copper layer is laminated after an aluminum layer is bonded to an insulating layer, but a pressurizing jig is simply obtained by directly laminating an aluminum layer and a copper layer. These metals slip sideways during assembly or pressurization, and misalignment is likely to occur (lateral displacement). Further, when octanediol is used as in the method described in Patent Document 2, since octanediol is a liquid at room temperature, there is a risk that a sufficient amount of adhesion cannot be ensured and a lateral shift may occur. Furthermore, the problem of lateral displacement between members may occur when the power module substrate and the heat sink are stacked (stacking of metals) or when stacking an insulating layer such as a ceramic substrate and a metal.

And since the deterioration of the stacking position accuracy due to the lateral shift that occurs between the members leads to a decrease in heat dissipation performance (increase in thermal resistance), a technology for preventing positional shift is desired.

The present invention has been made in view of such circumstances, and when joining the metal plates and between the metal plate and the ceramic plate, the positional displacement between the joining surfaces of the members is prevented, and these joined bodies are obtained. An object of the present invention is to provide a method for manufacturing a bonded body that can be efficiently manufactured, and to provide a method for manufacturing a power module substrate in which the method is applied to a power module substrate.

In the present invention, a temporary fixing material mainly composed of a saturated fatty acid is applied to any one of the first member made of a metal plate and the second member including one or more metal plates or ceramic plates, The first member stacked by stacking and aligning the first member and the second member via the temporary fixing material in a state where the temporary fixing material is melted, and cooling the temporary fixing material. A lamination process for forming a laminate in which a member and the second member are temporarily fixed, and a joined body in which the first member and the second member are joined by pressing and heating the laminate in the lamination direction. A bonding step of forming

In this manufacturing method, since the first member and the second member are temporarily fixed by the temporary fixing material mainly composed of saturated fatty acid, the first member and the second member are not displaced in the subsequent joining process. It is held in a positioned state. Therefore, the subsequent handling is facilitated, the productivity is improved, and the respective members can be joined in a precisely positioned state.

Temporary fixing material using saturated fatty acid that is solid at room temperature is melted and liquefied by heating. For this reason, after stacking the first member and the second member, the temporary fixing material is solidified by cooling to room temperature, and the first member and the second member can be easily bonded. Further, in the joining step, saturated fatty acids are quickly decomposed at a temperature sufficiently lower than the joining temperature, so that the joining surface between the first member and the second member is not affected.

Furthermore, saturated fatty acids have high fluidity in the liquefied molten state, and the first member and the second member are superposed on each other to quickly spread and maintain good bondability when in close contact with each other. it can.

Therefore, when joining the 1st member and 2nd member which are comprised with metal plates and a metal plate, a ceramic board, etc., position shift of the joining surfaces of each member can be prevented, and these joined bodies are made efficient. Can be manufactured.

In the method for manufacturing a joined body according to the present invention, the saturated fatty acid of the temporary fixing material may have 10 to 30 carbon atoms.

When the number of carbon atoms is less than 10, it becomes liquid at room temperature, so the handling property is poor, and when it exceeds 30, the melting point becomes high, so that the application workability to the first member and the second member is deteriorated. A saturated fatty acid having 10 to 30 carbon atoms has a melting point of about 32 ° C. to 94 ° C. and is solidified at room temperature, but it can be liquefied at a relatively low heating temperature, so that it is easy to handle. Excellent.

Examples of saturated fatty acids having 10 to 30 carbon atoms include capric acid having 10 carbon atoms, lauric acid having 12 carbon atoms, myristic acid having 14 carbon atoms, palmitic acid having 16 carbon atoms, and stearic acid having 18 carbon atoms. And melicic acid having 30 carbon atoms. Note that these saturated fatty acids are inexpensive and easily available.

In the manufacturing method of the joined body of the present invention, a bonding material layer is formed on the surface of either the first member or the second member, and the bonding step and the temporary fixing material are interposed in the laminating step. The first member and the second member may be laminated.

In the method for manufacturing a multilayer bonded body according to the present invention to which the above-described bonded body manufacturing method is applied, the third member made of a metal plate is temporarily fixed to the stacked body formed by the stacking process before the bonding process. A second stacking step, wherein in the second stacking step, a second temporary fixing material mainly composed of a saturated fatty acid having a melting point lower than that of the temporary fixing material is provided in either the laminate or the third member. Applying and laminating the second temporary fixing material at a temperature lower than the melting temperature of the temporary fixing material when laminating the laminated body and the third member, the laminated body and the third member Are aligned and laminated, and then the second temporary fixing material is cooled to form a second laminated body in which the laminated body and the third member are temporarily fixed. In the joining step, the second laminated layer is formed. By pressing and heating the body in its laminating direction, Further to form a multilayer assembly formed by bonding the third member relative to the joint body obtained by bonding the first member second member.

Also in the method for producing a multilayer joined body of the present invention, the saturated fatty acid of the temporary fixing material may have 10 to 30 carbon atoms. In addition, a bonding material layer is formed on a surface of either the first member or the second member, and the first member and the second member are interposed via the bonding material layer and the temporary fixing material in the stacking step. You may laminate | stack a member. Furthermore, a second bonding material layer is formed on the surface of either the second laminated body or the third member, and the second temporary fixing material and the second bonding material layer are interposed in the second lamination step. The laminated body and the third member may be laminated.

A method for manufacturing a power module substrate with a heat sink according to the present invention is a method for manufacturing a power module substrate with a heat sink to which the above-described multilayer assembly manufacturing method is applied, wherein the first member is made of copper or aluminum. And the second member is a ceramic substrate formed by laminating aluminum metal layers on both surfaces of a ceramic plate, the third member is a heat sink made of copper or aluminum, and in the joining step, While joining one side of the said aluminum metal layer of the said 2nd member, joining the other side of the said 2nd member said aluminum metal layer, and the said 3rd member, the board | substrate for power modules with a heat sink as said multilayer joined body Form.

The method for manufacturing a power module substrate according to the present invention is a method for manufacturing a power module substrate to which the above-described method for manufacturing a joined body is applied, wherein the first member is a copper circuit board, and the second member is a ceramic. A ceramic substrate in which aluminum metal layers are laminated on both surfaces of a plate, and one of the aluminum metal layers of the second member and the first member are bonded in the bonding step, and the power module substrate is used as the bonded body. Form.

A method for manufacturing a power module substrate with a heat sink according to the present invention is a method for manufacturing a power module substrate with a heat sink to which the manufacturing method for a joined body described above is applied, wherein the first member is a heat sink made of copper or aluminum, The second member is a power module substrate in which metal layers are laminated on both surfaces of a ceramic plate, and in the joining step, one of the metal layers of the second member and the first member are joined, A power module substrate with a heat sink is formed as a bonded body.

In this method of manufacturing a power module substrate with a heat sink, prior to the laminating step, the bonding material layer is temporarily fixed to the surface of either the first member or the second member by a bonding material layer temporary fixing material. In the laminating step, the temporary fixing material may be applied to either the first member or the second member where the bonding material layer is not formed.

The laminate manufacturing apparatus of the present invention includes a first member made of a metal plate and a second member including at least one metal plate or ceramic plate on either one of the first member and the second member. An apparatus for manufacturing a laminate, wherein the first member and the second member are temporarily bonded to each other by the formed temporary fixing material containing a saturated fatty acid as a main component, the first member or the first member Laminating means for conveying one of the two members on which the temporary fixing material is formed onto the other and laminating the first member and the second member; and the first member and the second member Heating means for melting the temporary fixing material when laminating.

Since the temporary fixing material using saturated fatty acid solid at normal temperature is melted by heating, it is necessary to put it in a heated state when laminating the first member and the second member. For this reason, the first member and the second member can be efficiently fixed by providing a heating means for heating the temporary fixing material when the first member and the second member are laminated.

Further, the laminate manufacturing apparatus of the present invention includes a first member made of a metal plate and a second member including at least one metal plate or ceramic plate, and one of the first member and the second member. An apparatus for manufacturing a laminate, wherein the first member and the second member are temporarily bonded to each other by a temporary fixing material mainly composed of a saturated fatty acid formed thereon, the first member or Laminating means for transporting the other of the second members onto one of the temporary members, and laminating the first member and the second member; and the first member and the second member And heating means for melting the temporary fixing material.

Since the saturated fatty acid, which is the main component of the temporary fixing material, has high fluidity in the liquefied molten state, when transporting one plate on which the temporary fixing material is formed, the molten temporary fixing material is bonded to In order to prevent adhering to an unnecessary position other than, it is desirable that the temporary fixing material is in a solidified state until just before the two members are laminated. Therefore, in the joined body manufacturing apparatus of the present invention, one plate on which the temporary fixing material is formed can be brought into a stationary state by conveying the other plate instead of the one plate on which the temporary fixing material is formed. Since it can do, it can prevent that a temporary fix | stop material adheres to an unnecessary position. Therefore, the first member and the second member can be efficiently fixed.

In the laminated body manufacturing apparatus of the present invention, it is preferable to include a cooling means for cooling the temporary fixing material after the first member and the second member are laminated.

The first member and the second member can be brought into an adhesive state by solidifying the temporary fixing material in a molten state by natural cooling, but the first member and the second member can be positively cooled by the cooling means. The state in which the member is aligned can be determined immediately.

According to the present invention, when joining the metal plates and between the metal plate and the ceramic plate, it is possible to prevent displacement of the joining surfaces of the respective members, so that these joined bodies can be manufactured efficiently.

It is sectional drawing of the board | substrate for power modules manufactured in 1st Embodiment of this invention. It is sectional drawing which showed typically the manufacturing process of the board | substrate for power modules of FIG. It is a schematic diagram explaining the manufacturing apparatus of the laminated body which concerns on this invention. It is a schematic diagram explaining the manufacturing method of 2nd Embodiment of this invention. It is a schematic diagram explaining the manufacturing method of 3rd Embodiment of this invention. It is a schematic diagram explaining the manufacturing method of 4th Embodiment of this invention. It is a schematic diagram explaining the manufacturing method of 5th Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described.

FIG. 1 shows a power module substrate 10 manufactured in the first embodiment of the present invention.

This power module substrate (the joined body of the present invention) 10 includes a copper circuit board (first member of the present invention) 30 and a ceramic substrate (invented in the present invention) in which aluminum metal layers 22 and 23 are laminated on both surfaces of the ceramic plate 21. A second member 20, and one aluminum metal layer 22 of the ceramic substrate 20 and the copper circuit board 30 are bonded to each other. In this case, the ceramic plate 21, the aluminum metal layers 22 and 23, and the copper circuit board 30 of the ceramic substrate 20 are formed in a rectangular planar shape.

The power module substrate 10 is soldered with an electronic component 60 such as a semiconductor chip on the surface of the copper circuit board 30, and a heat sink 50 is joined to the aluminum metal layer 23 disposed on the opposite side of the copper circuit board 30. A module.

The ceramic plate 21 is formed in a rectangular shape using, for example, a nitride ceramic such as AlN (aluminum nitride), Si ₃ N ₄ (silicon nitride), or an oxide ceramic such as Al ₂ O ₃ (alumina) as a base material. ing. The thickness of the ceramic plate 21 is 0.125 mm to 1.0 mm.

The aluminum metal layers 22 and 23 are made of pure aluminum or aluminum alloy (simply referred to as aluminum) having a purity of 99.90% or more, have a thickness of 0.1 mm to 3.0 mm, and are generally smaller than the ceramic plate 21. It is formed in a flat plate shape. The aluminum metal layers 22 and 23 are joined to the ceramic plate 21 by using a brazing material such as Al—Si, Al—Ge, Al—Cu, Al—Mg, or Al—Mn as a joining material.

The copper circuit board 30 is made of pure copper such as oxygen-free copper or tough pitch copper, or a copper alloy (simply referred to as copper in the present invention). The thickness of the copper circuit board 30 is 0.1 mm to 5.0 mm. As will be described later, the copper circuit board 30 is bonded to the aluminum metal layer 22 of the ceramic substrate 20 by solid phase diffusion bonding.

Next, a laminate manufacturing apparatus 90 (see FIG. 3) used for manufacturing the power module substrate 10 configured as described above will be described.

The laminated body manufacturing apparatus 90 uses the copper circuit board (first member of the present invention) 30 on which the temporary fixing material 40 mainly composed of saturated fatty acid is formed as the aluminum of the ceramic substrate (second member of the present invention) 20. The laminated body 80 temporarily fixed to the metal layer 22 is manufactured.

As shown in FIG. 3, the laminate manufacturing apparatus 90 according to the present embodiment places a base 91 on which the ceramic substrate 20 is placed and a copper circuit board 30 on which the temporary fixing material 40 is formed on the base 91. When laminating the copper circuit board 30 and the ceramic substrate 20, the laminating means 95 for laminating the copper circuit board 30 and the ceramic substrate 20 while being transported onto the placed ceramic substrate 20 and aligned with the ceramic substrate 20 Heating means 96 for melting the temporary fixing material 40.

As shown in FIGS. 3B and 3C, a plurality of guide pins 92 are erected on the base 91 on the mounting surface of the ceramic substrate 20 so as to surround the side surface of the ceramic substrate 20. The ceramic substrate 20 is positioned on the base 91 by placing the ceramic substrate 20 in a region surrounded by the guide pins 92.

As shown in FIGS. 3A and 3B, the stacking means 95 can be configured by a stacking pickup cylinder provided so as to be movable in the xyz axis direction, for example. The laminating means 95 conveys the copper circuit board 30 with the adhesion surface 30a facing downward to the base 91 on which the ceramic substrate 20 is placed, and the adhesion surface 30a of the copper circuit board 30 is placed on the base 91. The copper circuit board 30 and the ceramic substrate 20 are laminated by overlapping the ceramic substrate 20. Specifically, as shown in FIGS. 3A to 3C, the upper surface of the copper circuit board 30 opposite to the attachment surface 30a is air adsorbed by the laminating means 95, thereby conveying the copper circuit board 30.

The heating means 96 can be composed of, for example, a rubber heater as shown in FIG. 3A. By disposing the rubber heater (heating means) 96 with the adhesion surface 30a of the copper circuit board 30 facing each other, the temporary fixing material 40 of the adhesion surface 30a can be heated and melted.

The laminating means 95 is provided with a temperature measuring means 97 for observing the molten state of the temporary fixing material 40 when the copper circuit board 30 is conveyed. By measuring the temperature of the copper circuit board 30 by the temperature measuring means 97, when the copper circuit board 30 is heated by the heating means 96, the temporary fixing material 40 at each timing before and after the lamination of the copper circuit board 30 and the ceramic substrate 20 is measured. The molten state can be confirmed. As the temperature measuring means 97, for example, an infrared radiation thermometer can be used. In this embodiment, the temperature of the copper circuit board 30 held by the stacking means 95 is measured.

The laminate manufacturing apparatus 90 is provided with cooling means 98 for cooling the copper circuit board 30 and the ceramic substrate 20 after the lamination. As shown in FIG. 3C, the cooling means 98 can be constituted by a cooling nozzle that blows air, for example, and is provided in the stacking means 95.

Next, a method of manufacturing the power module substrate 10 by forming the stacked body 80 using the above-described stacked body manufacturing apparatus 90 will be described.

(Temporary fixing material application process)
First, as shown in FIG. 2A, a temporary fixing material 40 containing a saturated fatty acid as a main component is applied to one side of a copper circuit board (first member) 30. The temporary fixing material 40 is preferably a saturated fatty acid having 10 to 30 carbon atoms, solid at room temperature (25 ° C.), and having a relatively low melting point and undergoing phase transformation into a liquid. This is because when the number of carbon atoms is less than 10, it becomes liquid at room temperature, so the handling property is poor, and when it exceeds 30, the melting point becomes high, so that the workability of application to the copper circuit board 30 is deteriorated. On the other hand, saturated fatty acids having 10 to 30 carbon atoms have a melting point of about 32 ° C. to 94 ° C. and are solidified at room temperature, but can be liquefied at a relatively low heating temperature. Therefore, it is excellent in handleability.

The application of the temporary fixing material 40 to the copper circuit board 30 is performed using, for example, a hot cylinder, although illustration is omitted. In the hot cylinder, the temporary fixing material 40 is heated to a molten state, and the molten temporary fixing material 40 is dropped onto a plurality of locations such as corners on the surface of the copper circuit board 30. Then, the temporary fixing material 40 dripped onto the copper circuit board 30 is once cooled to room temperature and solidified to form the copper circuit board 30 to which the temporary fixing material 40 is adhered.

(Lamination process)
Next, as shown in FIG. 2B, the copper circuit board 30 to which the temporary fixing material 40 is applied in advance and the aluminum metal layer 22 of the ceramic substrate 20 are superposed on each other, and the copper circuit board 30 is formed by the temporary fixing material 40. And the ceramic substrate 20 are temporarily fixed.

The copper circuit board 30 is conveyed on the base 91 by the laminating means 95 (FIGS. 3A and 3B), and is superposed on the aluminum metal layer 22 of the ceramic substrate 20 placed in a positioning state on the base 91 (FIG. 3C). .

When the copper circuit board 30 is carried in, the applied temporary fixing material 40 is solidified. The temporary fixing material 40 can be melted by heating the adhesion surface 30a of the copper circuit board 30 against the rubber heater 96 in the middle of the transport path of the copper circuit board 30 by the laminating means 95.

Then, with the temporary fixing material 40 melted, the copper circuit board 30 is laminated on the ceramic substrate 20 as shown in FIGS. 2B and 3C. At this time, the temporary fixing material 40 adhering to the copper circuit board 30 is laminated with the ceramic substrate 20 so as to be thinly extended between the copper circuit board 30 and the aluminum metal layer 22 so as to be in close contact with each other. And the temporary fix | stop material 40 is cooled and solidifies by contacting the aluminum metal layer 22 which is not heated. Thereby, the laminated body 80 which fixed (temporarily fixed) the copper circuit board 30 and the ceramic substrate 20 in the state positioned correctly is obtained.

The temporary fixing material 40 can be solidified by natural cooling as described above, but can also be actively cooled and solidified by cooling means 98 as shown in FIG. 3C. In this case, the state in which the copper circuit board 30 and the ceramic substrate 20 are aligned can be determined immediately, and workability can be further improved.

(Joining process)
Then, as shown in FIG. 2C, the laminate 80 in which the copper circuit board 30 and the ceramic substrate 20 are temporarily fixed is pressed in the laminating direction and heated below the eutectic temperature of copper and aluminum, thereby producing a copper circuit. The power module substrate 10 can be manufactured by bonding the plate 30 and the aluminum metal layer 22 of the ceramic substrate 20 by solid-phase diffusion bonding by diffusing copper and aluminum mutually. Specifically, the aluminum metal layer 22 of the copper circuit board 30 and the ceramic substrate 20 is held in a vacuum atmosphere at a load of 0.3 MPa to 10 MPa and a heating temperature of 400 ° C. to less than 548 ° C. for 5 minutes to 240 minutes. Can be joined. The temporary fixing material 40 is decomposed and disappears in the initial stage of the heating.

As described above, in the method for manufacturing the power module substrate of the present embodiment, the copper circuit board (first member) 30 and the ceramic substrate 20 are temporarily fixed by the temporary fixing material 40 in the laminating step before the bonding step. Since the laminated body 80 is formed, it is possible to prevent the positional displacement between the copper circuit board 30 and the ceramic substrate 20 in the subsequent joining process, and the copper circuit board 30 is accurately positioned at a predetermined position on the ceramic substrate 20. Can be joined in a state.

Therefore, the power module substrate 10 can be efficiently manufactured, and productivity can be improved.

In the first embodiment described above, the temporary fixing material 40 is applied to the copper circuit board 30 and the copper circuit board 40 is transported and superimposed on the aluminum metal layer 22 of the ceramic substrate 20. The temporary fixing material 40 may be applied to the aluminum metal layer 22 of the substrate 20 and the copper circuit board 30 may be overlaid.

In this case, by superimposing the heated copper circuit board 30 on the aluminum metal layer 22 to which the temporary fixing material 40 is applied, the temporary fixing material 40 is melted by the heat of the copper circuit board 30, and the copper circuit board 30 and The aluminum metal layer 22 can be brought into a close contact state. Thereafter, the temporary fixing member 40 is cooled and solidified by the aluminum metal layer 22, and the copper circuit board 30 and the aluminum metal layer 22 can be fixed.

In this case, the ceramic substrate 20 on which the temporary fixing material 40 is formed can be brought into a stationary state by conveying the copper circuit board 30 instead of the ceramic substrate 20 on which the temporary fixing material 40 is formed. As a result, it is possible to prevent the molten temporary fixing material 40 from adhering to an unnecessary position other than the bonded portion, so that the copper circuit board 30 and the ceramic substrate 20 can be efficiently fixed.

The ceramic substrate 20 coated with the temporary fixing material 40 is adsorbed by the laminating means 95 and conveyed onto the base 91 on which the copper circuit board 30 is placed, and the ceramic substrate 20 is superimposed on the copper circuit board 30. You can also.

In the first embodiment, the temporary fixing material 40 dropped on the copper circuit board 30 is once cooled to room temperature and solidified, and then heated and temporarily fixed when the copper circuit board 30 is laminated on the ceramic substrate 20. Although the copper circuit board 30 and the ceramic substrate 20 were temporarily fixed by remelting the material 40, the temporary fixing material 40 dropped on the copper circuit board 30 was overlapped with the ceramic substrate 20 before being cooled. It is also possible to bond.

FIG. 4 shows a second embodiment of the present invention, and FIG. 4C shows a power module substrate (a joined body of the present invention) 11 manufactured according to the present invention. The power module substrate 11 includes an aluminum metal layer (first member of the present invention) 32 and a ceramic plate (second member of the present invention) 25 bonded to the aluminum metal layer 32. In this case, the aluminum metal layer 32 and the ceramic plate 25 are formed in a rectangular planar shape.

In order to manufacture the power module substrate 11 configured as described above, a brazing material foil is attached to one surface of the aluminum metal layer 32 by ultrasonic bonding or the like as shown in FIG. A bonding material layer 33 is formed in advance using a brazing material foil. Moreover, the temporary fixing material 41 which contains a saturated fatty acid as a main component is apply | coated to the surface of the joining material layer 33 similarly to the lamination process in 1st Embodiment. Then, the aluminum metal layer 32 and the ceramic plate 25 are overlapped with each other through the bonding material layer 33 in a state where the temporary fixing material 41 is melted, so that the molten temporary fixing material 41 is bonded to the ceramic plate 2 and the aluminum metal layer 32. The ceramic plate 25 and the aluminum metal layer 32 are in close contact with each other, being thinly extended between the bonding material layer 33 and forming a layer. Next, the temporary fixing material 41 is cooled in a state where the ceramic plate 25 and the aluminum metal layer 32 are positioned, thereby forming a laminated body 83 in which the ceramic plate 25 and the aluminum metal layer 32 are temporarily fixed (lamination step). .

As in the first embodiment, the ceramic plate 25 and the aluminum metal layer 32 are interposed between the ceramic plate 25 and the aluminum metal layer 32 by pressing the laminate in the stacking direction and heating in a vacuum. The power module substrate 11 can be manufactured by brazing with the bonding material layer 33 thus formed (bonding step).

In the second embodiment, the temporary fixing material 41 is attached to the surface of the bonding material layer 33 of the aluminum metal layer 32. However, the temporary fixing material 41 may be attached to the surface of the ceramic plate 25.

FIG. 5 shows a third embodiment of the present invention, and FIG. 5C shows a power module substrate with heat sink (joint of the present invention) 12 manufactured according to the present invention. The power module substrate 12 with a heat sink includes a heat module (first member of the present invention) 51 and a power module substrate in which aluminum metal layers 37 and 38 are brazed to both surfaces of the ceramic plate 36 (second member of the present invention). 35, and is manufactured by joining one aluminum metal layer 38 of the power module substrate 35 and the heat sink 51. The heat sink 51 is formed in a rectangular flat plate shape using pure aluminum or aluminum alloy (simply referred to as aluminum) having a purity of 99.90% or more.

In order to manufacture the power module substrate 12 with the heat sink configured as described above, the bonding material layer 55 is formed in advance on either the aluminum metal layer 38 or the heat sink 51 of the power module substrate 35. As the bonding material layer 55, for example, a clad material formed in three layers by laminating an Al—Si—Mg brazing material on both surfaces of a 3003 series aluminum alloy plate can be adopted.

As shown in FIG. 5A, a bonding material layer temporary fixing material 44 containing a saturated fatty acid as a main component is applied to the surface of the aluminum metal layer 38, and the bonding material layer temporary fixing material 44 is melted. Then, the aluminum metal layer 38 and the bonding material layer 55 are brought into close contact with each other via the bonding material layer temporary fixing material 44 by overlapping the bonding material layer 55. Then, the aluminum material layer 38 and the bonding material layer 55 are cooled, and the bonding material layer temporary fixing material 44 is cooled, whereby the aluminum metal layer 38 and the bonding material layer 55 are bonded (temporarily fixed).

Further, the same temporary fixing material 42 as the bonding material layer temporary fixing material 44 is applied to the surface of the heat sink 51, and the bonding material layer 55 is bonded onto the heat sink 51 in a state where the temporary fixing material 42 is melted. The power module substrate 35 and the heat sink 51 are brought into close contact with each other by superimposing the power module substrates 35 thus formed. And the laminated body 84 which temporarily fixed the power module substrate 35 and the heat sink 51 is formed by cooling the temporary fixing material 42 in a state where the power module substrate 35 and the heat sink 51 are positioned (stacking step). .

The laminated body 84 (the power module substrate 35 and the heat sink 51) is heated in a nitrogen atmosphere under atmospheric pressure while being pressed in the lamination direction, whereby the power module substrate 35 and the heat sink 51 are interposed therebetween. Then, the power module substrate 12 with a heat sink is manufactured by brazing with the bonding material layer 55 (bonding step).

FIG. 6 shows a fourth embodiment of the present invention, and FIG. 6C shows a power module substrate with heat sink (joint of the present invention) 13 manufactured according to the present invention. The power module substrate 13 with a heat sink includes a heat module (first member of the present invention) 52 and a power module substrate (a second member of the present invention) in which aluminum metal layers 47 and 48 are brazed to both surfaces of the ceramic plate 46. 45, and is manufactured by bonding one aluminum metal layer 48 of the power module substrate 45 and the heat sink 52. The heat sink 52 is formed in a rectangular flat plate shape from pure copper or a copper alloy (simply referred to as copper).

In order to manufacture the power module substrate 13 with a heat sink configured as described above, as shown in FIG. 6A, a temporary fixing material 43 containing a saturated fatty acid as a main component is applied to the power module substrate 45. The power module substrate 45 and the heat sink 52 are brought into close contact with each other through the temporary fixing material 43 by overlapping the heat sink 52 with the temporary fixing material 43 being melted. Then, by temporarily cooling the temporary fixing material 43 in a state where the power module substrate 45 and the heat sink 52 are positioned, the power module substrate 45 and the heat sink 52 are fixed and temporarily fixed by the temporary fixing material 43. 85 is formed (stacking step).

As in the first embodiment, the power source substrate 45 and the heat sink 52 are temporarily fixed, and the laminate 85 is pressurized in the laminating direction and heated below the eutectic temperature of copper and aluminum. The aluminum metal layer 48 of the module substrate 45 and the heat sink 52 are bonded to each other by solid phase diffusion bonding by diffusing copper and aluminum to each other to manufacture the power module substrate 13 with a heat sink (bonding step).

FIG. 7 shows a fifth embodiment of the present invention, and FIG. 7D shows a power module substrate with heat sink (multilayer joined body of the present invention) 14 manufactured according to the present invention. The power module substrate 14 with a heat sink includes a copper circuit board (first member of the present invention) 70 and a ceramic substrate (second member of the present invention) 75 in which aluminum metal layers 72 and 73 are laminated on both surfaces of the ceramic plate 71. And a heat sink (third member of the present invention) 53, and joins one aluminum metal layer 72 and the copper circuit board 70 of the ceramic substrate 75, and joins the other aluminum metal layer 73 and the heat sink 53. It is manufactured by. The heat sink 53 is formed in a rectangular flat plate shape from pure copper or a copper alloy (simply referred to as copper).

In order to manufacture the power module substrate 14 with the heat sink configured as described above, first, as shown in FIGS. 7A and 7B, a temporary fixing material 81 containing a saturated fatty acid as a main component is applied to the copper circuit board 70. In addition, the ceramic substrate 75 and the copper circuit board 70 are brought into close contact with each other through the temporary fixing material 81 by overlapping the ceramic substrate 75 with the temporary fixing material 81 being melted. Then, by cooling the temporary fixing material 81 in a state where the ceramic substrate 75 and the copper circuit board 70 are positioned, the laminated body in which the ceramic substrate 75 and the copper circuit board 70 are fixed and temporarily fixed by the temporary fixing material 81. 76 is formed (stacking step).

The temporary fixing material 81 can be attached to the surface of the ceramic substrate 75 (aluminum metal layer 72) instead of the copper circuit board 70.

Next, as shown in FIGS. 7B and 7C, an unsaturated fatty acid having a melting point lower than that of the temporary fixing material 81 is applied to the laminated body 76 in which the ceramic substrate 75 and the copper circuit board 70 formed in the lamination step are temporarily fixed. Temporarily fixed to the heat sink (the third member of the present invention) 53 by the second temporary fixing material 82 as the main component (second lamination step). For example, when a material mainly composed of stearic acid (18 carbon atoms, melting point: about 70 ° C.) is used as the temporary fixing material 81, the second temporary fixing material 82 has a sufficiently lower melting point than stearic acid. What has lauric acid (C12, melting | fusing point about 44 degreeC) as a main component can be used suitably.

When the laminated body 76 and the heat sink 53 are laminated, the second temporary fixing material 82 is applied to the aluminum metal layer 73 of the laminated body 76, and the second temporary fixing material 82 is melted by the temporary fixing material 81. The laminated body 76 and the heat sink 53 are brought into intimate contact with each other through the second temporary fixing material 82 by setting the laminated body 76 and the heat sink 53 to be in a state of being melted at a temperature lower than the temperature. Next, by cooling the second temporary fixing material 82, the laminated body 76 and the heat sink 53 are fixed by the second temporary fixing material 82, and the second laminated body 77 in which the laminated body 76 and the heat sink 53 are temporarily fixed is obtained. Form (second lamination step).

In the second stacking step, the second temporary fixing material 82 can be attached to the surface of the heat sink 53 instead of the aluminum metal layer 73 of the stacked body 76.

In this second lamination step, since the second temporary fixing material 82 having a melting temperature lower than the melting temperature of the temporary fixing material 81 temporarily fixing the copper circuit board 70 and the ceramic substrate 75 is used, the temporary fixing material 81 is used. The heat sink 53 can be temporarily fixed in a state where the copper circuit board 70 and the ceramic substrate 75 are fixed without melting. That is, the temporary stacking of the stacked body 76 and the heat sink 53 can be performed without causing a positional shift between the copper circuit board 70 and the ceramic substrate 75 in the second stacking step. Therefore, the three members of the copper circuit board 70, the ceramic substrate 75, and the heat sink 53 can be accurately positioned and fixed.

And the 2nd laminated body to which the copper circuit board 70, the ceramic substrate 75, and the heat sink 53 which were formed in this way were temporarily fixed was pressurized to the lamination direction similarly to 1st Embodiment, and copper and aluminum By heating below the eutectic temperature, copper and aluminum can be diffused to each other and bonded by solid phase diffusion bonding (bonding step). Thus, in the manufacturing method of the power module substrate with a heat sink of the fifth embodiment, the copper circuit board 70, the ceramic substrate 75, and the heat sink 53 can be bonded at the same time. Can be manufactured automatically.

In the fifth embodiment, between one aluminum metal layer 72 of the ceramic substrate 75 and the copper circuit board 70 and between the other aluminum metal layer 73 and the copper heat sink 53, copper and aluminum are used. The power module substrate 14 with a heat sink was manufactured by solid-phase diffusion bonding, but an aluminum circuit board was bonded to the aluminum metal layer 72 of the ceramic substrate 75, and an aluminum heat sink was bonded to the aluminum metal layer 73. You may join. In this case, a bonding material layer is formed in advance on either the aluminum metal layer 72 and the circuit board of the ceramic substrate 75, or on either the aluminum metal layer 73 or the heat sink, and each bonding material layer is formed between these members. Are stacked and temporarily fixed. As the bonding material layer, for example, a clad material formed in three layers by laminating Al—Si—Mg brazing material on both surfaces of a 3003 series aluminum alloy plate can be adopted.

Next, examples of the present invention and comparative examples performed for confirming the effects of the present invention will be described.

(Test 1)
As a conventional example and an example of the present invention, a temporary fixing material shown in Table 1 is dropped on a 30 mm × 30 mm rectangular, 1.0 mm thick copper plate, and a 25 mm × 25 mm rectangular, 0.6 mm thick aluminum plate is laminated. A temporarily bonded laminate was formed. Each laminate in the temporarily fixed state is confirmed by visually observing the lateral displacement generated in the aluminum plate by simulating the transport state of the laminate and shaking the copper plate of each laminate laterally at a speed of about 30 mm / s. Body bondability was evaluated. A case where the lateral deviation was 1 mm or less was judged as “excellent”, a case where the lateral deviation was more than 1 mm and less than 10 mm was judged as “good”, and a case where the lateral deviation occurred 10 mm or more was designated as “bad”. .

(Test 2)
Each laminate was pressurized at 1.0 MPa in the lamination direction in a vacuum atmosphere and heated at 540 ° C. for 60 minutes to form a joined body. Then, to simulate the usage state of the joined body, an ultrasonic image was obtained for each joined body in the initial state after joining and after being subjected to a cooling cycle between −40 ° C. and 100 ° C. 3000 times. With a measuring instrument, the presence or absence of an unjoined portion on the joint surface between the copper plate and the aluminum plate was observed. “Excellent” means that 2% or more unbonded part is not observed on the joint surface, and “bad” means that 5% or more unjoined part or void of 2 mm or more in diameter is recognized. , “Good” is a case where a slight unjoined portion that does not correspond to any of the above is recognized.
These results are shown in Table 1.

As can be seen from Table 1, in Examples 1 to 7 of the present invention, the lateral displacement between the copper plate and the aluminum plate in the laminated body is small by bonding the copper plate and the aluminum plate with a temporary fixing material, and the subsequent handling workability It was confirmed that it was good. In addition, a highly reliable bonding surface can be obtained without adversely affecting the bonding material layer.

In particular, in Examples 2 to 7 of the present invention using temporary fixing materials having 10 or more carbon atoms, there is almost no lateral deviation, and no adverse effects such as peeling of the bonding material layer can be obtained, and a highly reliable bonding surface can be obtained. Was confirmed.

It should be noted that the present invention is not limited to the configuration of the embodiment described above, and various modifications can be made in the detailed configuration without departing from the spirit of the present invention.

For example, although the embodiment in the case of manufacturing a power module substrate in which a copper circuit board and an aluminum metal layer and an aluminum metal layer and a ceramic substrate are joined has been described, the power module substrate having other configurations also includes a metal plate. The present invention can be applied when the first member and the second member made of a metal plate or a ceramic plate are joined.

In addition, the present invention can be applied to manufacturing a joined body of a first member and a second member used for applications other than the power module, and pressurizes these laminates. This includes the case of joining without heating and heating.

Furthermore, in the said embodiment, the 1st member and the 2nd member were made into the one-to-one relationship, and the joined body was manufactured, but it is not limited to this, One 2nd member has two or more things. The present invention can be applied to manufacturing various laminated bodies and bonded bodies, such as when the first member is bonded.

When joining the metal plates and between the metal plate and the ceramic plate, it is possible to prevent displacement of the joining surfaces of the respective members, so that these joined bodies can be manufactured efficiently.

10, 11 Power module substrate (joint)
12, 13 Power module substrate with heat sink (joint)
14 Power module substrate with heat sink (multilayer assembly)
20, 75 Ceramic substrate (second member)
21, 36, 46, 71

Ceramic plate

22, 23, 37, 38, 47, 48, 72, 73 Aluminum metal layer 25 Ceramic plate (second member)
30, 70 Copper circuit board (first member)
30a Adhesion surface 32 Aluminum metal layer (first member)
33, 55 Bonding material layers 35, 45 Power module substrate (second member)
40, 41, 42, 43, 81 Temporary fixing material 44 Temporary fixing material for bonding material layer 50

Heat sink

51, 52 Heat sink (first member)
53 Heat sink (third member)
60

Electronic parts

76, 80, 83, 84, 85 Laminated body 77 Second laminated body 82 Second temporary fixing material 90 Manufacturing apparatus 91 Base 92 Guide pin 95 Laminating means 96 Heating means (rubber heater)
97 Temperature measuring means 98 Cooling means

Claims

A temporary fixing material mainly composed of a saturated fatty acid is applied to either the first member made of a metal plate and the second member including one or more metal plates or ceramic plates, and the temporary fixing material is By laminating and aligning the first member and the second member via the temporary fixing material in the melted state, and cooling the temporary fixing material, the stacked first member and the first member A laminating step of forming a laminate in which two members are temporarily fixed;
A method for manufacturing a joined body, comprising: a joining step of forming a joined body in which the first member and the second member are joined by pressing and heating the laminated body in a laminating direction.
The method for producing a joined body according to claim 1, wherein the saturated fatty acid of the temporary fixing material has 10 to 30 carbon atoms.
A bonding material layer is formed on the surface of either the first member or the second member, and the first member and the second member are interposed via the bonding material layer and the temporary fixing material in the stacking step. The method for manufacturing a joined body according to claim 1, wherein:
A method for manufacturing a multilayer joined body to which the method for producing a joined body according to claim 1 is applied,
Before the joining step, it has a second lamination step of temporarily fixing a third member made of a metal plate to the laminate formed by the lamination step,
In the second lamination step, a second temporary fixing material mainly composed of a saturated fatty acid having a melting point lower than that of the temporary fixing material is applied to either the laminated body or the third member, and the laminated body And the third member, the second temporary fixing material is melted at a temperature lower than the melting temperature of the temporary fixing material, and the laminated body and the third member are aligned and laminated. By cooling the second temporary fixing material, a second laminated body in which the laminated body and the third member are temporarily fixed is formed,
In the joining step, the third member is further joined to the joined body obtained by joining the first member and the second member by pressing and heating the second laminated body in the laminating direction. A method for producing a multilayer joined body, comprising forming a multilayer joined body.
The method for producing a multilayer joined body according to claim 4, wherein the saturated fatty acid of the temporary fixing material has 10 to 30 carbon atoms.
A bonding material layer is formed on the surface of either the first member or the second member, and the first member and the second member are interposed via the bonding material layer and the temporary fixing material in the stacking step. The method for producing a multilayer joined body according to claim 4, wherein:
A second bonding material layer is formed on the surface of either the second laminated body or the third member, and the second temporary bonding material and the second bonding material layer are interposed in the second lamination step. The method for manufacturing a multilayer joined body according to claim 4, wherein the laminate and the third member are laminated.
A method for manufacturing a power module substrate with a heat sink, to which the method for manufacturing a multilayer joined body according to claim 4 is applied,
The first member is a circuit board made of copper or aluminum,
The second member is a ceramic substrate formed by laminating aluminum metal layers on both sides of a ceramic plate,
The third member is a heat sink made of copper or aluminum,
In the joining step, the first member and one of the aluminum metal layers of the second member are joined, and the other of the aluminum metal layers of the second member and the third member are joined, A method of manufacturing a power module substrate with a heat sink, comprising forming a power module substrate with a heat sink as a multilayer joined body.
The method for manufacturing a power module substrate with a heat sink according to claim 8, wherein the saturated fatty acid of the temporary fixing material has 10 to 30 carbon atoms.
A bonding material layer is formed on the surface of either the first member or the second member, and the first member and the second member are interposed via the bonding material layer and the temporary fixing material in the stacking step. The method for manufacturing a power module substrate with a heat sink according to claim 8, wherein:
A second bonding material layer is formed on the surface of either the second laminated body or the third member, and the second temporary bonding material and the second bonding material layer are interposed in the second lamination step. The method of manufacturing a power module substrate with a heat sink according to claim 8, wherein the laminate and the third member are laminated.
A method for manufacturing a power module substrate to which the method for manufacturing a joined body according to claim 1 is applied.
The first member is a copper circuit board,
The second member is a ceramic substrate formed by laminating aluminum metal layers on both sides of a ceramic plate,
In the joining step, one of the aluminum metal layers of the second member and the first member are joined to form a power module substrate as the joined body.
13. The method for manufacturing a power module substrate according to claim 12, wherein the saturated fatty acid of the temporary fixing material has 10 to 30 carbon atoms.
A bonding material layer is formed on the surface of either the first member or the second member, and the first member and the second member are interposed via the bonding material layer and the temporary fixing material in the stacking step. The method for manufacturing a power module substrate according to claim 12, wherein:
A method for manufacturing a substrate for a power module with a heat sink, to which the method for manufacturing a joined body according to claim 1 is applied,
The first member is a heat sink made of copper or aluminum,
The second member is a power module substrate in which metal layers are laminated on both sides of a ceramic plate,
A power module substrate with a heat sink is formed by joining one of the metal layers of the second member and the first member in the joining step to form a power module substrate with a heat sink as the joined body. Production method.
The method for producing a power module substrate with a heat sink according to claim 15, wherein the saturated fatty acid of the temporary fixing material has 10 to 30 carbon atoms.
A bonding material layer is formed on the surface of either the first member or the second member, and the first member and the second member are interposed via the bonding material layer and the temporary fixing material in the stacking step. The method for manufacturing a power module substrate with a heat sink according to claim 15, wherein:
Before the laminating step, the bonding material layer is temporarily fixed to the surface of either the first member or the second member with a bonding material layer temporary fixing material,
18. The power module with a heat sink according to claim 17, wherein in the laminating step, the temporary fixing material is applied to either the first member or the second member on which the bonding material layer is not formed. A method for manufacturing a substrate.
A first member made of a metal plate and a second member including at least one metal plate or ceramic plate are mainly composed of a saturated fatty acid formed on one of the first member and the second member. An apparatus for manufacturing a laminated body that temporarily fixes the first member and the second member in a state of being overlapped by a temporary fixing material,
Laminating means for conveying one of the first member or the second member on which the temporary fixing material is formed on the other and laminating the first member and the second member;
An apparatus for manufacturing a laminate, comprising: heating means for melting the temporary fixing material when the first member and the second member are laminated.
The apparatus for manufacturing a laminate according to claim 19, further comprising a cooling unit that cools the temporary fixing material after the first member and the second member are laminated.
A first member made of a metal plate and a second member including at least one metal plate or ceramic plate are mainly composed of a saturated fatty acid formed on one of the first member and the second member. An apparatus for manufacturing a laminated body that temporarily fixes the first member and the second member in a state of being overlapped by a temporary fixing material,
Laminating means for conveying the other on one of the first member or the second member on which the temporary fixing material is formed, and laminating the first member and the second member;
An apparatus for manufacturing a laminate, comprising: a heating unit that melts the temporary fixing material when the first member and the second member are laminated.
The apparatus for manufacturing a laminate according to claim 21, further comprising a cooling unit that cools the temporary fixing material after the first member and the second member are laminated.