JP2023041248A - Laminated structure and manufacturing method thereof - Google Patents

Abstract

To suppress remarkably Al-Ni alloying of an Al-based plate-like member in a laminated body obtained by a molten metal bonding method in which a ceramic plate, the Al-based plate-like member and a Ni plate are joined.SOLUTION: A ceramic plate and a Ni plate on one surface of which a coating film to form a ceramic film by heating is formed are placed in a mold with a gap therebetween so that the surface of the Ni plate on which the coating film is formed faces the ceramic plate, and molten Al or Al alloy is poured into the mold so that the molten metal filled in a space between the ceramic plate and the Ni plate is solidified to make a laminated structure in which the ceramic plate, the Al-based plate-like member comprising the Al or Al alloy and the Ni plate are joined together. The ceramic film is formed on a bonding interface between the Ni plate and the Al-based plate member.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a laminate structure in which a ceramic plate, an Al-based plate-like member, and a Ni plate are laminated and integrated, and a method for manufacturing the same, which is useful as an insulating circuit board for mounting a semiconductor element.

Semiconductor devices that generate a large amount of heat, such as power modules, generally use an insulated circuit board in which a plate-like circuit metal member is bonded to the surface of a ceramic plate, and the semiconductor element is soldered onto the circuit metal member. installed in such a way. As the circuit metal member, a Cu-based or Al-based metal material having good conductivity is applied. Of these, Al-based metal materials have poor solder wettability, and are generally used for soldering after their surfaces are plated with Ni.

In Patent Document 1, Ni plating is applied to the surface of an Al-based circuit metal member to a thickness of 17 μm as a method for improving durability against cracks in a solder layer in a heat cycle under severe conditions in which a semiconductor element generates a large amount of heat. Techniques for forming the film thicker than the above are disclosed. However, applying thick Ni plating to a predetermined circuit shape causes an increase in manufacturing cost.

In Patent Document 2, a Ni plate is formed by using a "melt bonding method" in which a ceramic plate and an Al-based circuit metal member are directly joined by solidifying molten Al-based metal on the surface of the ceramic plate. are simultaneously joined to the surface of the circuit metal member opposite to the ceramic plate.

JP 2018-18992 A JP 2020-132477 A

According to the method disclosed in Patent Document 2, in which the Ni plates are simultaneously joined using the molten metal joining method, the surface layer of the Ni plate can be formed at low cost in place of the thick Ni plating. However, with this method, the ceramic plate tends to warp, and there have been cases where cracks occur in the ceramic plate depending on the layout pattern of the circuit. The reason for this is that the surface layer of the Ni plate reacts with the molten Al-based metal during molten metal joining, and the Al-based circuit metal member after solidification becomes a metal structure mainly composed of a hard Al-Ni alloy. is mentioned. The layer of the circuit metal member, which is mainly made of hard Al-Ni alloy, shrinks by overcoming the restraining force from the ceramic plate with a small thermal expansion coefficient during cooling after molten metal joining, thereby causing the ceramic plate to warp. It is thought that a stress that causes

The present invention provides a laminate in which a ceramic plate, an Al-based plate-like member, and a Ni plate are joined and integrated, which can be formed by a molten metal bonding method, and the Al-Ni alloying of the Al-based plate-like member is remarkable. It is an object of the present invention to provide a restrained lamination structure.

As a result of research, the inventors discovered that by subjecting a Ni plate coated with a heat-resistant coating film containing an inorganic substance capable of forming a ceramic film at high temperatures to molten Al bonding, the surface layer portion of the Ni plate and Al The inventors have found that the reaction with the system molten metal is remarkably suppressed, and that the Ni plate and the Al-based plate-like member derived from the molten Al are satisfactorily joined. Based on this finding, the present specification discloses the following inventions.

[1] A laminated structure having a laminated portion in which a ceramic plate, an Al-based plate member made of Al or an Al alloy, and a Ni plate are laminated and joined in the above order, wherein the laminated portion includes: A laminated structure in which a ceramic film is formed on a bonding interface between an Al-based plate member and the Ni plate.
[2] The above-mentioned [1], wherein the ceramic film is an oxide ceramic film containing one or more elements selected from the group consisting of Co, Mn and Fe, or a nitride ceramic film containing Cr. laminated structure.
[3] The laminate according to [1] above, wherein the ceramic film is an oxide ceramic film containing one or more elements selected from the group consisting of Si and Ti, or a nitride ceramic film containing Cr. Structure.
[4] The ceramic film is an oxide ceramic film containing at least one element selected from the group consisting of Co, Mn and Fe and at least one element selected from the group consisting of Si and Ti, or Cr The laminated structure according to the above [1], which is a nitride-based ceramic film containing
[5] The above [1] to [4], wherein an Al-based rear member made of Al or an Al alloy is bonded to the surface of the ceramic plate opposite to the surface to which the Al-based plate member is bonded. The laminated structure according to any one of .
[6] The Al-based back member is a heat dissipating member in which the back portion of the ceramic plate is plate-shaped, or a heat dissipating member having fins or a plurality of pin-shaped projections in a portion other than the joint with the ceramic plate. The laminated structure according to any one of [1] to [5] above.
[7] The Al-based plate member has a thickness t between the ceramic plate and the Ni plate of 0.2 to 2.0 mm, and an average cross-sectional hardness determined by (A) below is 30.0 HV or less. , the laminated structure according to any one of the above [1] to [6].
(A) In a cross section obtained by buffing a cut surface parallel to the lamination direction of the laminated structure, the distance from the end in the lamination direction of the Ni plate side of the Al-based plate-like member is t ₁ (mm) defined below. Randomly set 5 or more measurement points, and measure the Vickers hardness at each measurement point at a test force F = 2.45 N in accordance with JIS Z2244-1: 2020. Let the arithmetic average value of the measured values be the cross-sectional average hardness.
Here, _t1 is set as follows.
When 0.2 mm≦t<0.7 mm, t ₁ =t/2±t/10 (mm)
When t≧0.7 mm, t ₁ =0.35±0.07 (mm)

The laminated structure described in [1] to [7] above can be obtained, for example, by the manufacturing method described below.
[8] A ceramic plate and a Ni plate on which a coating film that forms a ceramic film by heating is formed on one surface are spaced apart so that the surface of the Ni plate on which the coating film is formed faces the ceramic plate. a member placement step of placing in a mold and providing a space A between the ceramic plate and the Ni plate;
A molten metal of Al or an Al alloy is poured into the mold, and the molten metal filled in the space A is solidified to form a ceramic plate, an Al-based plate-like member made of Al or an Al alloy, and a Ni plate. a molten metal bonding step to form a bonded laminated structure;
A method of manufacturing a laminated structure comprising:
[9] The method for producing a laminated structure according to [8] above, wherein in the molten metal joining step, a ceramic film is formed on the joining interface between the Al-based plate member and the Ni plate.
[10] Manufacture of a laminated structure according to [8] above, wherein the coating contains oxide-based ceramic particles containing one or more elements selected from the group consisting of Co, Mn and Fe. Method.
[11] In the molten metal joining step, an oxide-based ceramic film containing at least one element selected from the group consisting of Co, Mn and Fe is formed at the joining interface between the Al-based plate member and the Ni plate. The method for manufacturing a laminated structure according to the above [10], wherein
[12] The method for producing a laminated structure according to [8] above, wherein the coating contains a resin containing one or more elements selected from the group consisting of Si and Ti.
[13] In the molten metal joining step, an oxide-based ceramic film containing one or more elements selected from the group consisting of Si and Ti is formed at the joint interface between the Al-based plate-shaped member and the Ni plate. The method for producing a laminated structure according to [12] above.
[14] The coating film comprises oxide-based ceramic particles containing at least one element selected from the group consisting of Co, Mn and Fe, and a resin containing at least one element selected from the group consisting of Si and Ti. The method for producing a laminated structure according to [8] above, which contains
[15] In the molten metal joining step, one or more elements selected from the group consisting of Co, Mn and Fe and one selected from the group consisting of Si and Ti are added to the joint interface between the Al-based plate member and the Ni plate. The method for producing a laminated structure according to [14] above, wherein an oxide-based ceramic film containing one or more elements is formed.
[16] The method for producing a laminated structure according to [8] above, wherein the coating contains nitride ceramic particles containing Cr.
[17] The method for producing a laminated structure according to [16] above, wherein a nitride-based ceramic film containing Cr is formed on a bonding interface between the Al-based plate member and the Ni plate in the molten metal bonding step. .
[18] The method for producing a laminated structure according to any one of [8] to [17] above, wherein the coating film is a dry coating film from which volatile components have been volatilized and removed in advance.
[19] The laminated structure according to any one of [8] to [18] above, wherein the coating film has the property of becoming a ceramic film in a temperature range of 700°C or less when the temperature is raised from room temperature. manufacturing method.
[20] In the member arrangement step, a space B is provided between the back surface of the ceramic plate facing the Ni plate and the mold wall surface,
In the molten metal joining step, by solidifying the molten metal filled in the space A and the space B, the ceramic plate, the Al-based plate-like member made of Al or an Al alloy, and the Ni plate are joined, and Any one of the above [8] to [19], wherein a laminated structure is formed in which an Al-based back member made of Al or an Al alloy is bonded to the back of the surface of the ceramic plate on which the Al-based plate-shaped member exists. A method for manufacturing a laminated structure.
[21] The method for producing a laminated structure according to [20] above, wherein the Al-based back member is a plate-shaped heat radiating member on the back portion of the ceramic plate.
[22] The above-mentioned [ 20].

Here, "a ceramic plate, an Al-based plate-shaped member made of Al or an Al alloy, and a Ni plate are laminated and joined in the above order" described in [1] above means the laminated member In the positional relationship of , an Al-based plate-like member made of Al or Al alloy exists next to the ceramic plate, and a Ni plate exists next to the Al-based plate-like member on the opposite side of the ceramic plate. . That is, there are bonding interfaces between the ceramic plate and the Al-based plate-like member made of Al or Al alloy, and between the Al-based plate-like member and the Ni plate.

Oxide-based ceramics refer to ceramics composed of inorganic substances containing oxides as the main component. Nitride-based ceramics refer to ceramics composed of an inorganic substance containing nitride as a main component. Here, "having an oxide as a main component" means that the mass ratio of the oxide to the inorganic substance constituting the ceramic is 50% or more. Similarly, "mainly composed of nitrides" means that the mass ratio of nitrides to the inorganic substances constituting the ceramics is 50% or more.

According to the present invention, in a laminated structure in which a ceramic plate, an Al-based plate-like member, and a Ni plate are joined by a molten metal bonding method using an Al-based molten metal, the Al-based plate-like member is made into an Al—Ni alloy. It was possible to realize a layered structure that was remarkably suppressed. The insulated circuit board using this laminated structure has less warpage of the ceramic plate and is more durable than conventional Ni plate products in which a hard Al-Ni alloy is formed when the Ni plate is welded with molten metal. is also excellent. Moreover, since complicated Ni-plating is not required, it is advantageous in terms of productivity and manufacturing cost compared to conventional general Ni-plated products.

The figure which showed typically the cross-sectional structure of the laminated part which the laminated structure of this invention has. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view schematically showing an example of the cross-sectional structure of an insulated circuit board using the laminated structure of the present invention; BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view schematically showing an example of the cross-sectional structure of an insulated circuit board using the laminated structure of the present invention; FIG. 3 is a cross-sectional view schematically illustrating the arrangement in a mold for producing the laminated structure having the cross-sectional structure shown in FIG. 2 by the molten metal bonding method; FIG. 4 is a cross-sectional view schematically illustrating an arrangement in a mold for producing a laminated structure having the cross-sectional structure shown in FIG. 3 by a molten metal bonding method; FIG. 5 is a cross-sectional view illustrating a state in which molten metal is introduced into the mold shown in FIG. 4; FIG. 6 is a cross-sectional view illustrating a state in which molten metal is introduced into the mold shown in FIG. 5; FIG. 2 is a diagram illustrating an SEM (scanning electron microscope) observation image of a cross section including the bonding interface between the Ni plate and the Al-based plate-like member of the laminated structure obtained in Example 1; FIG. 9 is a diagram showing a monochromatic map analysis color image by EDS (energy dispersive X-ray spectroscopy) of Al, Ni, O, Co, Mn, Fe, Si, and Ti for the portion corresponding to FIG. 8 ; FIG. 4 is a diagram illustrating an appearance photograph of a cross-sectional sample after hardness measurement of the laminated structure obtained in Example 1;

[Laminated structure]
FIG. 1 schematically illustrates the cross-sectional structure of the laminated portion of the laminated structure of the present invention. A ceramic plate 10, an Al-based plate-shaped member 20 made of Al or an Al alloy, and a Ni plate 30 are laminated and joined together, and these members are integrated. A ceramic film 140 is formed on the joint interface between the Al-based plate member 20 and the Ni plate 30 . This laminated structure is used as an insulating circuit board. A semiconductor element is mounted on the upper surface of the Ni plate 30 via a solder layer or the like. The Al-based plate member 20 constitutes a circuit metal member of an insulated circuit board.

Typical ceramics that are the main component of the ceramic plate 10 include AlN (aluminum nitride) with good thermal conductivity, Si ₃ N ₄ (silicon nitride) with high strength, and inexpensive and versatile Al ₂ O ₃ (alumina). ) and the like. In the case of a power module, it is preferable to use an AlN plate or _{a Si3N4} plate from the viewpoint of ensuring reliability and heat dissipation. The thickness of the ceramic plate 10 varies depending on the design of the insulating circuit board. preferable.

A pure Ni plate containing 99.0% by mass or more of Ni is applied to the Ni plate 30 . The Ni content of the Ni plate 30 is preferably 99.5% by mass or more, more preferably 99.7% by mass or more.

The Al-based plate-shaped member 20 is made of Al or an Al alloy, and is formed by solidifying molten Al or Al alloy in the space between the ceramic plate 10 and the Ni plate 30 by a molten metal joining method, which will be described later. The thickness of the Al-based plate member 20 can be set, for example, in the range of 0.2 to 2.0 mm, more preferably 0.4 to 1.5 mm.

It is preferable that the Al-based plate-shaped member 20 is sufficiently suppressed from being hardened due to the mixing of Ni. Specifically, when the thickness t of the Al-based plate member 20 between the ceramic plate 10 and the Ni plate 30 is 0.2 mm or more, the cross-sectional average hardness of the Al-based plate member 20 is 30.0 HV. The following is extremely effective in reducing the warpage of the ceramic plate 10 . More preferably, the average cross-sectional hardness of the Al-based plate member 20 is 26.0 HV or less. The cross-sectional average hardness of the Al-based plate member 20 can be determined as follows.

(Method for measuring average cross-sectional hardness of Al-based plate member)
In a cross-section obtained by buffing a cut surface parallel to the lamination direction of the laminated structure, the distance from the end in the lamination direction of the Ni plate side of the Al-based plate-shaped member is t ₁ (mm) defined below. Randomly set 5 or more points, measure the Vickers hardness at each measurement point at a test force F = 2.45 N in accordance with JIS Z2244-1: 2020, and measure the measured value at each measurement point. Let the arithmetic mean value be the cross-sectional average hardness.
Here, _t1 is set as follows.
When 0.2 mm≦t<0.7 mm, t ₁ =t/2±t/10 (mm)
When t≧0.7 mm, t ₁ =0.35±0.07 (mm)

For example, when the thickness t of the Al-based plate-shaped member 20 is 0.3 mm, the distance t ₁ from the end of the Al-based plate-shaped member 20 on the side of the Ni plate 30 in the stacking direction is given by the following equation, t ₁ = 0.3/2 ± 0.3/10 = 0.15 ± 0.03 (mm). do. When the thickness t of the Al-based plate-shaped member 20 is 1.2 mm, the distance t ₁ from the end of the Al-based plate-shaped member 20 on the side of the Ni plate 30 in the stacking direction is given by the following equation, t ₁ =0 A test force F is applied so that the center of the indenter for Vickers hardness measurement is positioned at a stacking direction position that satisfies 0.35±0.07 (mm).

If Ni is mixed from the Ni plate 30 into the Al-based plate member 20, the Al—Ni alloying effect on the hardness of the region of the Al-based plate member 20 near the Ni plate 30 increases. When the thickness t of the Al-based plate-like member 20 is large, even if Ni is mixed, the degree of hardening is small in a region far from the Ni plate 30 . According to the inventor's study, if the thickness t of the Al-based plate-shaped member 20 is up to about 0.7 mm, the degree of hardening due to Ni mixing is determined by the thickness of the Al-based plate-shaped member 20. It can be evaluated by the cross-sectional hardness at the central portion. However, when the thickness t of the Al-based plate-shaped member 20 increases, the position of the central portion of the thickness moves away from the Ni plate 30, so that the degree of hardening is sufficiently determined by the cross-sectional hardness at the central portion of the thickness. It becomes impossible to evaluate. Therefore, when the thickness t of the Al-based plate-like member 20 is 0.7 mm or more, the distance from the Ni plate 30 is 0.7 mm as a measurement position at which the influence of Ni contamination on hardness can be fully grasped. A position of about 35 mm is adopted. ±0.07 mm is the allowable variation width.

The Ni plate 30 replaces the Ni plating that has been generally applied to insulated circuit boards that employ Al-based circuit metal members, and is mainly used to prevent solder wetting during soldering when joining semiconductor elements. It has a role in improving sexuality. The thickness of the Ni plate 30 is preferably 0.05-1.0 mm, more preferably 0.1-0.5 mm. Since Ni has a lower thermal conductivity than Al-based materials, if the Ni plate 30 is too thick, it is disadvantageous in terms of heat radiation performance. If the thickness of the Ni plate 30 is too thin, the Ni plate with the coating formed thereon is difficult to handle when set in the mold.

The ceramic film 140 is preferably an oxide ceramic film or a nitride ceramic film. Examples of oxide-based ceramic films include those containing one or more selected from the group consisting of Co, Mn and Fe, and those containing one or more selected from the group consisting of Si and Ti. In particular, one containing one or more selected from the group consisting of Co, Mn and Fe and one or more selected from the group consisting of Si and Ti is more preferred. Nitride-based ceramic films include those containing Cr. When the Al-based plate member 20 is formed by the molten metal bonding method, when the molten Al-based material comes into direct contact with the surface of the Ni plate, the surface layer of the Ni-based plate reacts with the molten Al-based metal, and Ni is mixed into the molten Al-based metal. After solidification, the Al-based plate member 20 presents a metal structure mainly composed of a hard Al--Ni alloy. The Al-Ni alloying of the Al-based plate-like member 20 causes warping and cracking of the ceramic plate as described above. In the laminated structure of the present invention, a ceramic film 140 derived from a coating film, which will be described later, is formed on the surface of the Ni plate 30 at the time of melt bonding using the Al-based molten metal, so that the Ni plate and the Al-based molten metal are directly connected. contact is avoided. As a result, the Al-Ni alloying of the Al-based plate member 20 is remarkably suppressed. In addition, in the laminated structure of the present invention obtained by molten metal bonding, the ceramic film 140 existing at the bonding interface between the Al-based plate-like member 20 and the Ni plate 30 is formed between the Al-based plate-like member 20 and the Ni plate 30. Responsible for good bonding. The film thickness of the ceramic film 140 is preferably in the range of 1-15 μm, more preferably in the range of 2-10 μm. The thicker the ceramic film 140 is, the more advantageous it is for suppressing the diffusion of Ni into the Al-based alloy member. In FIG. 1, the thickness of the ceramic film 140 is exaggerated (the same applies to FIGS. 2, 3, 6 and 7).

FIG. 2 schematically shows an example of a cross-sectional structure of an insulated circuit board using the laminated structure of the present invention. An Al-based plate member 20, which is a metal member for circuits, is bonded to one side surface of the ceramic plate 10. As shown in FIG. The Al-based plate member 20 is arranged according to the circuit pattern. Here, a cross section of a portion where two Al-based plate members 20 are juxtaposed is illustrated. The two Al-based plate members 20 are electrically insulated from each other by grooves 21 formed on the ceramic plate 10 . A Ni plate 30 is bonded onto each Al-based plate member 20 . The ceramic film 140 described above is formed on the bonding interface between the Al-based plate member 20 and the Ni plate 30, respectively. That is, the ceramic plate 10, the Al-based plate-shaped member 20, and the Ni plate 30 have a laminated portion in which they are laminated and bonded in the above order, and the bonding interface between the Al-based plate-shaped member 20 and the Ni plate 30 A laminated structure is constructed in which the ceramic film 140 is formed on the . The Al-based plate member 20 can be formed by the molten metal joining method as described above.
Although FIG. 2 shows a state in which the Ni plate 30 is bonded to the entire surface of the Al-based plate-like member 20, the Ni plate is attached only to a partial region where an electronic component such as a semiconductor element is soldered. 30 may be joined.

An Al-based rear member 50 made of Al or an Al alloy is bonded to the surface of the ceramic plate 10 opposite to the surface to which the Al-based plate member 20 is bonded. This Al-based back member 50 has a function as a heat dissipation member. In the example of FIG. 2 , the end of the Al-based back member 50 in the direction perpendicular to the thickness direction is integrated with the peripheral wall 51 that surrounds the end face of the ceramic plate 10 . That is, the Al-based back member 50 shown in FIG. It is formed around the surface on which the Al-based plate member 20 is formed. The peripheral wall portion 51 and the Al-based plate member 20 are electrically insulated from each other by a groove portion 52 formed on the ceramic plate 10 . In the Al-based back member 50, the back portion of the ceramic plate 10 (the portion of the Al-based back member 50 on the side opposite to the surface of the ceramic plate 10 to which the Al-based plate-like member 20 is joined) is plate-shaped. It's becoming The Al-based back member 50 and the peripheral wall portion 51 can be formed by casting Al-based molten metal using the molten metal joining process for forming the Al-based plate-shaped member 20 .

FIG. 3 schematically shows an example of a cross-sectional structure of an insulated circuit board using the laminated structure of the present invention. In this example, an Al-based back member 50 of a type having a plurality of pin-like protrusions 53 is applied to the insulating circuit board shown in FIG. Depending on the arrangement of the pin-shaped projections 53, a part of the pin-shaped projections behind may be seen from between the pin-shaped projections 53 shown in FIG. 3, but the illustration of the pin-shaped projections behind is omitted here. . The pin-shaped protrusion 53 has a heat sink function for enhancing heat dissipation. The pin-shaped projections 53 can also be formed by casting Al-based molten metal together with the Al-based back member 50 using the molten metal joining process for forming the Al-based plate member 20 . As a member for enhancing heat dissipation, a heat dissipation fin made of a plate-like member can be formed by casting using the process of joining molten metal.

[Production method]
The laminated structure of the present invention can be manufactured by the "melt joining method" in which the space between the ceramic plate and the Ni plate in the mold is filled with Al-based molten metal. At that time, as the Ni plate, a plate whose surface in contact with the Al-based molten metal is coated with a coating film having excellent heat resistance is used. The coating suppresses the reaction between the Ni plate and the Al-based molten metal during welding of the molten metal.

There are various kinds of so-called heat-resistant coating films. According to the study of the inventor, it was found that it is effective to apply a coating film that forms a ceramic film by heating. Considering the pouring temperature of molten Al in the molten metal joining method, a coating film that forms a ceramic film by heating up to 700° C. is desirable. That is, a coating film having a property of becoming a ceramic film in a temperature range of 700° C. or less, preferably 650° C. or less when the temperature is raised from room temperature is suitable. In addition, it is desired that the ceramic film is a heat-resistant coating film that does not easily react with Al-based molten metal and that can stably continue to cover the surface of the Ni plate up to about 800°C.

It is desirable that the volatile components of the coating film covering the surface of the Ni plate are sufficiently removed by volatilization before contact with the Al-based molten metal. In this specification, the volatile components (moisture and volatile organic components) contained in the paint used to form the coating film are sufficiently volatilized in advance by keeping at room temperature or preheating. called "coating". Preheating for obtaining a dry coating film may be performed in advance before setting the Ni plate with the coating film formed in the mold, or after setting the Ni plate with the coating film in the mold, start pouring the molten metal. Prior to heating, the heating process during heating of the mold in the furnace may be utilized.

According to the knowledge of the inventors so far, the following two types of coating films are highly effective in coating the surface of the Ni plate and significantly suppressing the reaction between the Ni plate and the Al-based molten metal when the molten metal is joined. can be done.
(1) Coating that forms an oxide-based ceramic film by heating This type of coating includes ceramic particles composed of oxides of transition metals, and one or more selected from the group consisting of Si and Ti. Coating films containing resins can be mentioned. Examples of the former ceramic particles include oxide ceramic particles containing one or more elements selected from the group consisting of Co, Mn and Fe. Examples of the latter resin include polymers having Si--O bonds and Ti--O bonds, such as silicone resins and tyranno resins. A coating film containing oxide-based ceramic particles containing at least one element selected from the group consisting of Co, Mn and Fe and a resin containing at least one element selected from the group consisting of Si and Ti is more desirable. Effective.
(2) Coating Film Forming a Nitride Ceramic Film by Heating This type of coating film includes a coating film containing nitride ceramic particles containing Cr.

As a method for forming the coating film, for example, a spray method, a dipping method (immersion method), a coating method, or the like can be employed depending on the properties of the coating material. Here, the paint includes a liquid or paste that has a relatively high viscosity and is suitable for application, and a coating liquid that is suitable for spraying and dipping. Examples of coating methods include a bar coater method, a die coater method, a roll coater method, and a brush coating method. Examples of a treatment method for obtaining a dry coating film include a method of keeping the Ni plate coated with the coating film at room temperature, and a method of preheating the Ni plate at a predetermined temperature of, for example, 400° C. or lower. There is also a method of forming a dry coating film in which the Ni plate is dipped in a coating liquid and then dried a plurality of times to increase the amount of coating film components adhered to the Ni plate surface. The effect of suppressing the reaction between the Ni plate and the Al-based molten metal increases as the thickness of the coating film increases, but on the other hand, the thickness of the formed ceramic film increases, which is disadvantageous in terms of heat dissipation. There is According to studies by the inventors, the film thickness of the coating film is preferably set in the range of 1 to 15 μm, more preferably in the range of 2 to 10 μm. The coating film may be formed on a Ni plate cut into a predetermined size, or may be formed on a long Ni plate in a continuous coating line. In the latter case, a Ni plate component of a predetermined size is cut out from a long Ni plate on which a coating film is formed. Formation of the coating film and preheating for obtaining a dry coating film can be performed continuously in a continuous coating line.

Using the Ni plate coated on one side with the coating film of (1) or (2) in this way, a laminated structure is manufactured in the following process including a "member placement step" and a "melt bonding step". obtain.

[Member placement process]
When performing molten metal joining, first, a Ni plate having the coating film formed on one surface thereof and a ceramic plate are placed in a mold so that the surface of the Ni plate on which the coating film is formed faces the ceramic plate. are placed with a space between them.

FIG. 4 shows a cross-sectional view schematically illustrating the arrangement in the mold for producing the laminated structure having the cross-sectional structure shown in FIG. A mold 1 is composed of an upper mold 1a and a lower mold 1b. The upper mold 1a and the lower mold 1b are made of a gas-permeable carbon material or metal material. The casting mold 1 has a hot water reservoir 5 formed by the internal spaces of the upper mold 1a and the lower mold 1b. The hot water storage part 5 is a space for containing molten metal to be supplied to the product shape space inside the mold. An Al-based molten metal can also be obtained by melting an Al-based metal raw material in the hot water storage section 5 . In that case, the hot water storage part 5 also functions as a crucible. A pressurization port 2 is provided in the upper part of the hot water storage part 5, and a pressure for sending the molten metal in the hot water storage part 5 into the product shape space is applied from the outside of the mold 1 through the pressure port 2 to the molten metal. . The lower mold 1b is provided with a runner 3 for supplying the molten metal in the hot water storage part 5 to each part in the mold. In the example of FIG. 4, a part of the runner 3 is provided with a narrow cross-section channel 103 in which the cross section of the channel through which the molten metal passes is narrowed. When the Al-based molten metal passes through the narrow cross-section flow path 103, the oxide film on the surface of the molten metal is removed.

The Ni plate 30 and the ceramic plate 10 are placed at predetermined positions on the lower mold 1b with a gap therebetween. At that time, the surface of the Ni plate 30 covered with the coating film 40 faces the ceramic plate 10 . A space A is formed between the Ni plate 30 and the ceramic plate 10 . The space A is connected to the hot water storage part 5 by a runner (not shown) in the lower die 1b. By solidifying the Al-based molten metal filled in the space A, an Al-based plate member (reference numeral 20 in FIG. 2), which is a circuit metal member, is formed. A space B is formed between the upper surface of the ceramic plate 10 and the mold wall surface of the upper mold 1a. The space B is connected to the hot water storage part 5 by a runner inside the lower mold 1b. By solidifying the Al-based molten metal filled in the space B, an Al-based back member (reference numeral 50 in FIG. 2), which is a heat radiating member, is formed.
In FIG. 4, the thickness of the coating film 40 is exaggerated (the same applies to FIG. 5).

FIG. 5 shows a cross-sectional view schematically illustrating the arrangement in the mold for producing the laminated structure having the cross-sectional structure shown in FIG. In this case, the space B has a plurality of pin-shaped recesses 4 formed by the wall surface of the upper die 1a. A pin-shaped protrusion (reference numeral 53 in FIG. 3) having a heat sink function is formed by solidifying the Al-based molten metal filled in the pin-shaped concave portion 4 . The mold structure of FIG. 5 is similar to that of FIG. 4, except that pin-shaped recesses 4 are formed. The arrangement of the Ni plate 30 and the ceramic plate 10 placed on the lower mold 1b is also the same as in FIG. The mold 1 has a structure for supporting or sandwiching the ceramic plate 10 so that the ceramic plate 10 does not shift from a predetermined position during the molten metal joining process.

[Molten metal joining process]
6 and 7 are cross-sectional views of the molds shown in FIGS. 4 and 5, respectively, in which molten metal is introduced. Casting for joining molten metal is performed, for example, as follows. A casting mold 1 is prepared in which the Ni plate 30 on which a coating film (reference numeral 40 in FIGS. 4 and 5) is formed and the ceramic plate 10 are set as described above. When the hot water storage part 5 is used as a crucible, the hot water storage part 5 is filled with Al-based metal granules or the like, which are raw materials for the Al-based molten metal. The mold 1 is put into a heating furnace and heated in a non-oxidizing gas atmosphere such as nitrogen gas. If the formation of the dry coating film by preheating has not been completed, the temperature rising process of this heating can be used to form the dry coating film. In that case, the temperature of the mold may be increased by a heat pattern in which the temperature is maintained in a predetermined temperature range of 400° C. or less for a certain period of time. When Al-based molten metal melted in a melting furnace outside the mold 1 is used, the molten metal is introduced from the pressure port 2 into the hot water storage portion 5 . When the hot water storage part 5 is used as a crucible, the raw Al-based metal is melted in the hot water storage part 5 to obtain an Al-based molten metal.

After the mold reaches a predetermined temperature (eg, 700 to 720° C.), it is pressurized with an inert gas such as nitrogen gas from the pressurizing port 2 at a pressure of, for example, 5 to 50 kPa, and the Al-based Molten metal 100 (that is, molten Al or Al alloy) is poured into the space within the mold via runners 3 . In the examples of FIGS. 6 and 7, the Al-based molten metal 100 passes through the narrow cross-sectional flow path 103 to remove the oxide film formed on the surface of the molten metal. It is considered that the coating film covering the surface of the Ni plate 30 is formed into the ceramic film 140 by sintering and hardening of coating film components due to heating of the mold before the start of molten metal pouring. Even if the ceramic film 140 is not sufficiently formed at that time, when the space A between the Ni plate 30 and the ceramic plate 10 is filled with the Al-based molten metal 100, the formation of the ceramic film progresses rapidly. The surface of the Ni plate 30 is protected with a ceramics film 140 . This ceramic film 140 remarkably suppresses the reaction between the Ni plate and the Al-based molten metal 100 .

After all spaces in the mold connected by runners are filled with Al-based molten metal 100, solidification is started. As a solidification method, it is preferable to effect directional solidification by contacting a part of the outer wall of the mold 1 (for example, the left end in FIGS. 6 and 7) with a water-cooled copper block as a cooling device. In order to prevent casting defects such as shrinkage cavities, it is desirable to proceed with solidification while continuing pressurization at a pressure of, for example, 5 to 50 kPa using an inert gas such as nitrogen gas from the pressurization port 2 . In the Al-based plate-shaped member (reference numeral 20 in FIGS. 2 and 3) formed by solidifying the Al-based molten metal 100 in the space A, the presence of the ceramic film 140 significantly suppresses Ni contamination from the Ni plate. This avoids hardening due to Al—Ni alloying.

[Etching process]
In order to manufacture an insulated circuit board for mounting a semiconductor element using the laminated structure obtained as described above, unnecessary Al-based metal such as the runner portion of the laminated structure taken out from the mold is removed. must be removed. Generally, the runner portion having a relatively large volume is removed by machining such as cutting, and circuit pattern formation and dimensional adjustment are performed by chemical etching. In the latter removal treatment, after the surface of the Ni plate is coated with a resist film, the unnecessary Al-based metal can be dissolved and removed using a chemical solution. In addition, since the Ni plate is sufficiently thicker than the conventional Ni plating layer, it is possible to omit the formation of the resist film and perform etching in anticipation of the Ni plate surface being somewhat dissolved. In this case, etching is preferably performed using a chemical solution having a higher Al dissolution rate than Ni so that a Ni layer having a predetermined thickness remains sufficiently. As a chemical solution in which the dissolution rate of Al is higher than the dissolution rate of Ni, a ferric chloride aqueous solution can be exemplified. The etching temperature (chemical solution temperature) is preferably 45 to 60.degree.

[Example 1]
As the Ni plate, a pure Ni plate (containing 99.9% by mass or more of Ni, tempered H (hard material)) having a thickness of 0.5 mm and a size of 14 mm×14 mm manufactured by Hitachi Metals Neomaterial Co., Ltd. was prepared. A coating film containing ceramic particles containing Co, Mn and Fe as oxides was formed on one side of the Ni plate which had been buffed. As a paint for forming a coating film, Tyranocoat TYR-1181, a heat-resistant paint manufactured by Okitsumo Co., Ltd., was used. A coating film was formed by a spray method so that the wet coating film thickness was several μm. After forming the coating film, the Ni plate was held in the air at 120°C for 10 minutes, and then subjected to a preheating treatment in which it was held in the air at 380°C for 15 minutes to volatilize and remove volatile components to form a dry coating film. .

As a ceramic plate, an AlN plate manufactured by Tokuyama Corporation and having a thickness of 0.635 mm and a size of 71 mm×70 mm was prepared. Using two Ni plates on which the above dried coating film was formed, two Al-based plate-like members having a size of 14 mm × 14 mm when viewed in the lamination direction and having a Ni plate on the surface were prepared for each ceramic plate. A laminated structure having a portion was produced as follows. As shown in FIG. 5, the Ni plate and the ceramic plate were placed in a mold made of a gas-permeable carbon material with a gap therebetween so that the coating film forming surface of the Ni plate faced the ceramic plate. The distance between the coating surface of the Ni plate and the ceramic plate (space A in FIG. 5) was 1.2 mm. After putting pure Al granules with a purity of 3N (Al content of 99.9% by mass or more) as an Al raw material into the hot water storage part (reference numeral 5 in FIG. 5) of this mold, the mold was put into a furnace and a nitrogen atmosphere was placed. heated inside. The heating temperature was monitored by a thermocouple attached to the mold. After the Al raw material was melted, a pressure of 16 kPa was applied with nitrogen gas from the pressurizing port (reference numeral 2 in FIG. 7) of the mold at a temperature of 720° C., and a narrow cross-sectional flow path (reference numeral 103 in FIG. 7) provided in the runner was applied. Al-based molten metal is injected into the space inside the mold (space A in FIG. 7) via the narrow cross-sectional flow path (not shown in FIG. 7) provided in another runner (not shown in FIG. 7). Al-based molten metal was injected into the space inside the mold (space B in FIG. 7) via the mold. About 4 minutes after the start of the pouring, directional solidification was started by contacting a water-cooled copper block as a cooling device to the outer wall of the end of the mold (the part corresponding to the left end in FIG. 7). Solidification was allowed to proceed while continuing to pressurize with nitrogen gas and supply the molten metal from the hot water reservoir. After the temperature of the mold reached about 50° C. or less, the inside of the furnace was opened to the atmosphere, and the cast product (laminated structure) was taken out from the mold. In this manner, a plurality of Al-based plate-like members corresponding to circuit metal members are provided on one side of the ceramic plate, and an Al-based back member having pin-like projections is provided on the other side of the ceramic plate. A laminated structure was obtained. The thickness of the Al-based plate member having a 0.5 mm thick Ni plate on its surface is 1.2 mm.

The laminated structure removed from the mold was cut in a cross section parallel to the lamination direction to prepare an observation sample for elemental analysis of a portion including the interface between the Ni plate and the Al-based plate-like member. The observation surface was prepared by polishing with diamond abrasive grains (three stages of particle sizes of 9 μm, 3 μm, and 1 μm). A region of this observation surface including the bonding interface between the Ni plate and the Al-based plate-shaped member is observed with a SEM (scanning electron microscope, manufactured by JEOL Ltd., JSM-6390A), and EDS (energy dispersive X-ray analysis). Elemental analysis was performed by Qualitative analysis by EDS detected Al, Ni, Mn, Fe, Co, Si, Ti, Ca, and O in the region including the joint interface. FIG. 8 illustrates an SEM image. FIG. 9 exemplifies EDS map analysis images of Al, Ni, O, Co, Mn, Fe, Si, and Ti in the portion corresponding to FIG. The element is distributed in bright spots other than black. O, Co, Mn, Fe, Si, and Ti are found at the joint interface between the Ni plate and the Al-based plate member. Mixing of Ni into the Al-based plate-shaped member side is remarkably suppressed, and growth of the metal phase of the Al—Ni alloy is not observed. It is thought that an oxide-based ceramics film containing Ni was formed, and that film functioned as a protective film on the surface of the Ni plate, thereby remarkably avoiding reaction with the Al-based molten metal. The average film thickness of this ceramic film (the average width in the stacking direction of the region where O, Co, Mn, Fe, Si, and Ti are distributed in a film form) was about 7 μm.

(Cross-sectional hardness of Al-based plate-shaped member)
The laminated structure removed from the mold was cut in a cross section parallel to the lamination direction to prepare a cross-sectional sample of a portion including the Ni plate--the Al-based plate-like member--the ceramics plate. The surface of the sample was finished by buffing. Using this cross-sectional sample, the cross-sectional hardness of the Al-based plate member formed between the Ni plate and the ceramic plate was measured. The measuring method followed the method described in the above-mentioned "Method for measuring cross-sectional average hardness of Al-based plate-shaped member". In this example, the thickness t of the Al-based plate member is 1.2 mm. The center of the indenter for Vickers hardness measurement is placed at a position in the lamination direction where the distance t ₁ from the end in the lamination direction of the Ni plate side of the Al-based plate member satisfies the following equation: t ₁ = 0.35 ± 0.07 mm A test force F (2.45 N) was applied so that As a result, the measured values (HV) for the number of tests n = 5 were 25.4, 25.4, 24.8, 25.0, and 26.0. The cross-sectional average hardness of the plate member was 25.32HV.
For reference, hardness was also measured at positions in the stacking direction at a distance of 0.35±0.07 mm from the stacking direction end of the Al-based plate member on the ceramic plate side. As a result, the measured values (HV) of the test number n = 5 were 25.2, 24.4, 25.0, 25.0, 25.1, and their average hardness was 24.94 HV. rice field.
In the laminated structure obtained in this example, it was confirmed that the hardness of the Al-based plate-like member was kept low, and that the variation in hardness depending on the location was very small.

FIG. 10 shows an appearance photograph of a cross-sectional sample after hardness measurement. In this photograph, a position at a distance of 0.35±0.07 mm from the end of the stacking direction on the Ni plate side and a position at a distance of 0.35±0.07 mm from the end of the stacking direction on the ceramic plate side. Indentations made by pressing the indenter at two locations can be seen at each position.

(Heat cycle characteristics)
A laminated structure prepared under the same conditions as above was repeatedly subjected to 300 heat cycles of -40°C for 30 minutes, 25°C for 10 minutes, 150°C for 30 minutes, and 25°C for 10 minutes. Later, with respect to the portion of the Al-based plate-shaped member having the Ni plate on its upper surface, the bonding interface between the Ni plate and the Al-based plate-shaped member and the bonding interface between the Al-based plate-shaped member and the ceramic plate were observed with an ultrasonic flaw detector. . As a result, even after 300 cycles, no peeling (void) was observed at the bonding interface between the Ni plate and the Al-based plate-like member and the bonding interface between the Al-based plate-like member and the ceramic plate. Similarly, the presence or absence of cracks in the ceramic substrate after 300 cycles was observed with an ultrasonic flaw detector. As a result, no cracks were observed in the ceramic substrate.

(solder wettability)
After the surface of the Ni plate of the laminated structure was buffed, it was washed with dilute sulfuric acid, washed with water, and dried, and the solder wettability of the nickel plate was evaluated. A flux-containing solder paste containing 3% by mass of Ag and 0.5% by mass of Cu, with the balance being Sn, was applied to a Ni plate to a thickness of 0.5 mm, and was soldered in a nitrogen atmosphere at 270° C. in a soldering furnace. C. for 3 minutes and allowed to cool, the area ratio of the surface of the Ni plate wetted with solder (solder wettability) was measured. It was good.

[Example 2]
An experiment was conducted under the same conditions as in Example 1, except that a coating film containing ceramic particles containing Cr as a nitride was used as the coating film formed on the surface of the Ni plate. A heat-resistant paint IAR manufactured by Japan ITF Co., Ltd. was used as a paint for forming a coating film. A coating film having a thickness of about several μm was formed on one side surface of the Ni plate by a method (dip method) of immersing the Ni plate in the coating liquid of this paint.

As a result of SEM observation and EDS analysis of a cross-section parallel to the lamination direction of the laminated structure obtained by the molten metal bonding method, mixing of Ni into the Al-based plate member was recognized. However, compared with Comparative Example 1 described later, the reaction between the Ni plate and the Al-based molten metal was greatly suppressed. The presence of nitrides containing Cr was observed at the joint interface between the Ni plate and the Al-based plate member. Since the mixing of Ni into the Al-based plate-shaped member is remarkably suppressed, a ceramic film containing Cr as a nitride is formed on the bonding interface, and the film functions as a protective film on the surface of the Ni plate. , the reaction with Al-based molten metal is considered to be remarkably avoided. The average film thickness of this ceramic film (the average width in the stacking direction of the region where nitrides containing Cr are distributed) was about 3 μm.

(Cross-sectional hardness of Al-based plate-shaped member)
As a result of measuring the cross-sectional hardness of the Al-based plate-shaped member formed between the Ni plate and the ceramic plate in the same manner as in Example 1, the distance _t1 from the end in the stacking direction on the Ni plate side was 0.35 ± The measured values (HV) for n = 5 tests at a position of 0.07 mm were 22.2, 24.8, 24.1, 23.2, 22.9, the laminate obtained in this example. The cross-sectional average hardness of the Al-based plate member of the structure was 23.44HV.
In addition, the measured values (HV) of the number of tests n = 5 at the position where the distance from the end of the stacking direction on the ceramic plate side is 0.35 ± 0.07 mm are 21.0, 20.8, and 23.1. , 22.8, 21.3 and their average hardness was 21.80 HV.
In the laminated structure obtained in this example, the hardness of the Al-based plate-like member was kept low compared to Comparative Example 1 described later.

(Heat cycle characteristics)
When the heat cycle characteristics of the laminated structure were evaluated in the same manner as in Example 1, even after 300 cycles, the bonding interface between the Ni plate and the Al-based plate-shaped member and the bonding between the Al-based plate-shaped member and the ceramic plate No peeling (void) was observed at the interface, and no cracks were observed in the ceramic substrate.

(solder wettability)
When the solder wettability of the Ni plate of the laminated structure was measured by the same method as in Example 1, the solder wettability was 95% or more, and the solder wettability of the Ni plate was good.

[Comparative Example 1]
An experiment was conducted under the same conditions as in Example 1, except that a Ni plate having no coating film formed on its surface (without a coating layer) was used.

SEM observation and EDS analysis of a cross section parallel to the lamination direction of the laminated structure obtained by the molten metal bonding method were performed. As a result, mixing of Ni into the Al-based plate-shaped member was observed, and the Al-based plate-shaped member exhibited a metal structure in which a phase with a high Ni content was mixed in the Al phase, forming an Al--Ni alloy.

As a result of measuring the cross-sectional hardness of the Al-based plate-shaped member formed between the Ni plate and the ceramic plate, the test was performed at a position where the distance _t1 from the end in the stacking direction of the Ni plate was 0.35 ± 0.07 mm. The measured values (HV) of the number n = 5 are 42.5, 40.7, 41.0, 39.6, and 36.8, and the Al-based plate members of the laminated structure obtained in this example The cross-sectional average hardness was 40.12HV.
In addition, the measured values (HV) of the number of tests n = 5 at the position where the distance from the end of the stacking direction on the ceramic plate side is 0.35 ± 0.07 mm are 34.3, 31.8, and 32.6. , 32.8, 30.9 and their average hardness was 32.48 HV.
In this example, the Al-based molten metal was brought into direct contact with the Ni plate, so that the solidified Al-based plate-shaped metal member was made into an Al—Ni alloy and hardened.

(Heat cycle characteristics)
When the heat cycle characteristics of the laminated structure were evaluated in the same manner as in Example 1, cracks were observed in the ceramic substrate after 100 cycles.

[Comparative Example 2]
A laminated structure was produced under the same conditions as in Example 1, except that the Ni plate was not placed in the mold. The laminated structure has the same shape as in Example 1, except that the Al-based plate-like member does not have a Ni plate on its surface.

(Heat cycle characteristics)
When the heat cycle characteristics of the laminate structure were evaluated in the same manner as in Example 1, no cracks were observed in the ceramic substrate after 300 cycles.

REFERENCE SIGNS LIST 1 mold 1a upper mold 1b lower mold 2 pressurizing port 3 runner 4 pin-shaped concave portion 5 hot water storage portion 10 ceramic plate 20 Al-based plate-like member 21 groove portion 30 Ni plate 40 coating film 50 Al-based back member 51 peripheral wall portion 52 groove portion 53 Pin-shaped protrusion 100 Molten metal 103 Narrow cross-section flow path 140 Ceramic film

Claims (22)

A laminated structure having a laminated portion in which a ceramic plate, an Al-based plate-shaped member made of Al or an Al alloy, and a Ni plate are laminated and joined in the above order, wherein the laminated portion includes the Al-based plate A laminated structure in which a ceramic film is formed on the bonding interface between the shaped member and the Ni plate. The laminated structure according to claim 1, wherein the ceramic film is an oxide ceramic film containing one or more elements selected from the group consisting of Co, Mn and Fe, or a nitride ceramic film containing Cr. . 2. The laminated structure according to claim 1, wherein said ceramic film is an oxide ceramic film containing at least one element selected from the group consisting of Si and Ti, or a nitride ceramic film containing Cr. The ceramic film is an oxide ceramic film containing at least one element selected from the group consisting of Co, Mn and Fe and at least one element selected from the group consisting of Si and Ti, or a nitriding film containing Cr. 2. The laminated structure according to claim 1, which is a solid-state ceramics film. 5. The method according to any one of claims 1 to 4, wherein an Al-based rear member made of Al or an Al alloy is bonded to the surface of the ceramic plate opposite to the surface to which the Al-based plate member is bonded. Laminate structure as described. 2. The Al-based back member is a heat radiating member in which the back portion of the ceramic plate is plate-shaped, or a heat radiating member having fins or a plurality of pin-like protrusions in a portion other than the joint portion with the ceramic plate. 6. The laminated structure according to any one of 1 to 5. The Al-based plate member has a thickness t of 0.2 to 2.0 mm between the ceramic plate and the Ni plate, and an average cross-sectional hardness determined by (A) below is 30.0 HV or less. 7. The laminated structure according to any one of 1 to 6.
(A) In a cross section obtained by buffing a cut surface parallel to the lamination direction of the laminated structure, the distance from the end in the lamination direction of the Ni plate side of the Al-based plate-like member is t ₁ (mm) defined below. Randomly set 5 or more measurement points, and measure the Vickers hardness at each measurement point at a test force F = 2.45 N in accordance with JIS Z2244-1: 2020. Let the arithmetic average value of the measured values be the cross-sectional average hardness.
Here, _t1 is set as follows.
When 0.2 mm≦t<0.7 mm, t ₁ =t/2±t/10 (mm)
When t≧0.7 mm, t ₁ =0.35±0.07 (mm) A ceramic plate and a Ni plate having a coating film that forms a ceramic film by heating on one side thereof are placed in a mold with a gap therebetween so that the surface of the Ni plate on which the coating film is formed faces the ceramic plate. A member placement step of providing a space A between the ceramic plate and the Ni plate,
A molten metal of Al or an Al alloy is poured into the mold, and the molten metal filled in the space A is solidified to form a ceramic plate, an Al-based plate-like member made of Al or an Al alloy, and a Ni plate. a molten metal bonding step to form a bonded laminated structure;
A method of manufacturing a laminated structure comprising: 9. The method for manufacturing a laminated structure according to claim 8, wherein in said molten metal joining step, a ceramic film is formed on a joining interface between said Al-based plate member and said Ni plate. 9. The method for producing a laminated structure according to claim 8, wherein said coating contains oxide-based ceramic particles containing at least one element selected from the group consisting of Co, Mn and Fe. In the molten metal joining step, an oxide-based ceramic film containing at least one element selected from the group consisting of Co, Mn and Fe is formed at the joining interface between the Al-based plate member and the Ni plate. Item 11. A method for manufacturing a laminated structure according to Item 10. 9. The method for manufacturing a laminated structure according to claim 8, wherein said coating film contains a resin containing one or more elements selected from the group consisting of Si and Ti. 12. An oxide-based ceramic film containing one or more elements selected from the group consisting of Si and Ti is formed on a bonding interface between the Al-based plate member and the Ni plate in the molten metal bonding step. 3. The method for manufacturing the laminated structure according to 1. The coating film contains oxide ceramic particles containing at least one element selected from the group consisting of Co, Mn and Fe, and a resin containing at least one element selected from the group consisting of Si and Ti. The method for manufacturing a laminated structure according to claim 8, wherein In the molten metal joining step, at least one element selected from the group consisting of Co, Mn and Fe and one selected from the group consisting of Si and Ti are added to the joint interface between the Al-based plate member and the Ni plate. 15. The method for manufacturing a laminated structure according to claim 14, wherein an oxide-based ceramic film containing the above elements is formed. 9. The method of manufacturing a laminated structure according to claim 8, wherein said coating contains nitride ceramic particles containing Cr. 17. The method of manufacturing a laminated structure according to claim 16, wherein in said molten metal joining step, a nitride-based ceramic film containing Cr is formed on a joining interface between said Al-based plate member and said Ni plate. The method for producing a laminated structure according to any one of claims 8 to 17, wherein the coating film is a dry coating film from which volatile components have been volatilized and removed in advance. The method for manufacturing a laminated structure according to any one of claims 8 to 18, wherein the coating film has the property of becoming a ceramic film in a temperature range of 700°C or less when the temperature is raised from room temperature. In the member arrangement step, a space B is provided between the back surface of the ceramic plate facing the Ni plate and the mold wall surface,
In the molten metal joining step, by solidifying the molten metal filled in the space A and the space B, the ceramic plate, the Al-based plate-like member made of Al or an Al alloy, and the Ni plate are joined, and 20. The laminate structure according to any one of claims 8 to 19, wherein an Al-based back member made of Al or an Al alloy is bonded to the back of the surface of the ceramic plate on which the Al-based plate-shaped member exists. A method for manufacturing a laminated structure. 21. The method of manufacturing a laminated structure according to claim 20, wherein the Al-based back member is a plate-shaped heat radiating member having a back portion of the ceramic plate. 21. The method according to claim 20, wherein the space B has a fin-shaped gap or a plurality of pin-shaped recesses formed by the wall surface of the mold, and the Al-based back member is a heat dissipation member having fins or a plurality of pin-shaped projections. A method for manufacturing a laminated structure of

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