Method for manufacturing Fe-based metal / ceramic bonded body, Fe-based metal / ceramic bonded body, and Fe-based metal / Al clad material

Abstract

The present invention provides a method for manufacturing an Fe-based metal / ceramic bond that exhibits excellent insulation properties without migration and can suppress cracking when subjected to thermal cycling. [Solution] A method for manufacturing an Fe-based metal / ceramic bond, comprising joining an Fe-based metal member made of a metal containing Fe and a ceramic member, characterized in that it comprises a lamination step of laminating the ceramic member and the Fe-based metal member via a bonding material containing Al, and a bonding step of heating the laminated ceramic member, the bonding material, and the Fe-based metal member while applying pressure in the lamination direction to bond the ceramic member and the Fe-based metal member.

Description

Technical Field

[0001] This invention relates to a method for manufacturing an Fe-based metal / ceramics joined body in which an Fe-based metal member made of a metal containing Fe and a ceramics member are joined, an Fe-based metal / ceramics joined body, and an Fe-based metal / Al clad material.

Background Art

[0002] [[ID=1...]]An Fe-based metal / ceramics joined body in which an Fe-based metal member made of a metal containing Fe and a ceramics member are joined is used, for example, as a constituent material for semiconductor manufacturing apparatuses, precision parts, crystal oscillators, relay parts, and the like. Conventionally, examples of methods for joining an Fe-based metal member and a ceramics member include those disclosed in Patent Documents 1 and 2.

[0003] In Patent Document 1, a method is disclosed in which after performing a metallization treatment on the joining surface of the ceramics member, the ceramics member and the Fe-based metal member are joined using an Ag-Cu-based brazing material. In Patent Document 2, a method is disclosed in which the Fe-based metal member and the ceramics member are joined using a brazing material containing Ag, Cu, and an active metal (Ti).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] As described above, in Patent Documents 1 and 2, since a brazing material containing Ag is used to join Fe-based metal members and ceramic members, Ag is present at the joining interface, which makes migration likely to occur when used under high temperature and high humidity conditions, and therefore it could not be used for high-pressure applications. Furthermore, when brazing materials containing active metals were used, the joint layer hardened, and there was a risk of cracking and fracture at the joint interface when subjected to thermal cycling.

[0006] This invention has been made in view of the circumstances described above, and aims to provide a method for manufacturing an Fe-based metal / ceramic bond, an Fe-based metal / ceramic bond, and an Fe-based metal / Al clad material that can be suitably used in the method for manufacturing an Fe-based metal / ceramic bond, which is free from migration, has excellent insulating properties, and can suppress cracking when subjected to thermal cycling. [Means for solving the problem]

[0007] To solve the aforementioned problems, the method for manufacturing an Fe-based metal / ceramic bond according to Embodiment 1 of the present invention is a method for manufacturing an Fe-based metal / ceramic bond comprising an Fe-based metal member made of a metal containing Fe and a ceramic member, characterized in that it comprises a lamination step of laminating the ceramic member and the Fe-based metal member via a bonding material containing Al, and a bonding step of heating the laminated ceramic member, the bonding material, and the Fe-based metal member while applying pressure in the lamination direction to bond the ceramic member and the Fe-based metal member.

[0008] In the method for manufacturing an Fe-based metal / ceramic bond according to Embodiment 1 of the present invention, the method comprises a lamination step of laminating the ceramic member and the Fe-based metal member via a bonding material containing Al, and a bonding step of heating the laminated ceramic member, bonding material, and Fe-based metal member while applying pressure in the lamination direction to bond the ceramic member and the Fe-based metal member. As a result, there is almost no Ag or active metal at the bonding interface. Therefore, even when used under high temperature and high humidity conditions, Ag migration does not occur, and insulating properties can be ensured. Furthermore, the bonding interface does not harden due to active metals, and cracking at the bonding interface during thermal cycling loads can be suppressed. Therefore, it becomes possible to manufacture Fe-based metal / ceramic bonding bodies with excellent insulation properties and thermal cycling reliability.

[0009] The method for manufacturing an Fe-based metal / ceramic bond according to aspect 2 of the present invention is characterized in that, in the method for manufacturing an Fe-based metal / ceramic bond according to aspect 1, the bonding material has a structure in which a high-melting-point Al layer and a low-melting-point Al layer are laminated, and in the lamination process, the low-melting-point Al layer is laminated so as to face the ceramic member side.

[0010] In the method for manufacturing an Fe-based metal / ceramic bond according to aspect 2 of the present invention, the bonding material has a structure in which a high-melting-point Al layer and a low-melting-point Al layer are laminated, and in the lamination process the low-melting-point Al layer is laminated so that it faces the ceramic member side, the low-melting-point Al layer functions as a brazing material, and the ceramic member and the Fe-based metal member can be joined together. Furthermore, after bonding, an Al intermediate layer is formed between the Fe-based compound layer and the ceramic member. This Al intermediate layer acts as a buffer layer, further improving the reliability of the thermal cycle.

[0011] A method for manufacturing an Fe-based metal / ceramic bond according to Embodiment 3 of the present invention is characterized in that, in the method for manufacturing an Fe-based metal / ceramic bond according to Embodiment 1, the bonding material comprises a high-melting-point Al layer, a low-melting-point Al layer formed on one side of the high-melting-point Al layer, and a second low-melting-point Al layer formed on the other side of the high-melting-point Al layer, and in the lamination step, the low-melting-point Al layer is laminated so that it faces the ceramic member side and the second low-melting-point Al layer faces the Fe-based metal member side.

[0012] In the method for manufacturing an Fe-based metal / ceramic bond according to aspect 3 of the present invention, the bonding material comprises a high-melting-point Al layer, a low-melting-point Al layer formed on one side of the high-melting-point Al layer, and a second low-melting-point Al layer formed on the other side of the high-melting-point Al layer. In the lamination process, the low-melting-point Al layer faces the ceramic member side and the second low-melting-point Al layer faces the Fe-based metal member side. As a result, the low-melting-point Al layer and the second low-melting-point Al layer function as brazing materials to bond the ceramic member and the Fe-based metal member. Furthermore, after bonding, an Al intermediate layer is formed between the Fe-based compound layer and the ceramic member. This Al intermediate layer acts as a buffer layer, further improving the reliability of the thermal cycle.

[0013] A method for manufacturing an Fe-based metal / ceramic joint according to aspect 4 of the present invention is a method for manufacturing an Fe-based metal / ceramic joint comprising a Fe-based metal member made of a metal containing Fe and a ceramic member joined together, comprising: an Fe-based metal / Al clad material preparation step of preparing an Fe-based metal / Al clad material by laminating and joining an Fe-based metal member made of a metal containing Fe and a low-melting-point Al layer; a lamination step of laminating the ceramic member and the Fe-based metal / Al clad material; and a joining step of heating the laminated ceramic member and the Fe-based metal / Al clad material while applying pressure in the lamination direction to join the ceramic member and the Fe-based metal / Al clad material, wherein in the lamination step, the low-melting-point Al layer is laminated facing the ceramic member side.

[0014] In the method for manufacturing an Fe-based metal / ceramic bond according to aspect 4 of the present invention, there is an Fe-based metal / Al clad material preparation step in which an Fe-based metal member and a low-melting-point Al layer are laminated and joined together to form an Fe-based metal / Al clad material. In the lamination step, the ceramic member and the Fe-based metal / Al clad material are laminated such that the low-melting-point Al layer faces the ceramic member, so that the low-melting-point Al layer acts as a brazing agent, making it possible to join the Fe-based metal / Al clad material and the ceramic member. Furthermore, because there is virtually no Ag or active metal present at the bonding interface, Ag migration does not occur even when used under high temperature and high humidity conditions, ensuring insulation. In addition, the bonding interface does not harden due to active metals, which suppresses cracking at the bonding interface during thermal cycling loads. Therefore, it becomes possible to manufacture Fe-based metal / ceramic bonding bodies with excellent insulation properties and thermal cycling reliability. Furthermore, after bonding, an Al intermediate layer is formed between the Fe-based compound layer and the ceramic member. This Al intermediate layer acts as a buffer layer, further improving the reliability of the thermal cycle.

[0015] The method for manufacturing an Fe-based metal / ceramic bond according to aspect 5 of the present invention is characterized in that, in the method for manufacturing an Fe-based metal / ceramic bond according to aspect 4, a high-melting-point Al layer is formed between the Fe-based metal member and the low-melting-point Al layer.

[0016] In the method for manufacturing an Fe-based metal / ceramic bond according to aspect 5 of the present invention, since a high-melting-point Al layer is formed between the Fe-based metal member and the low-melting-point Al layer in the Fe-based metal / Al clad material, after bonding, an Al intermediate layer of sufficient thickness is formed between the Fe-based compound layer and the ceramic member, and the Al intermediate layer acts as a buffer layer, making it possible to further improve the reliability of the thermal cycle.

[0017] The manufacturing method of the Fe-based metal / ceramics joined body of Aspect 6 of the present invention is characterized in that, in the manufacturing method of the Fe-based metal / ceramics joined body of Aspect 5, a second low melting point Al layer is formed between the Fe-based metal member and the high melting point Al layer in the Fe-based metal / Al clad material.

[0018] In the manufacturing method of the Fe-based metal / ceramics joined body of Aspect 6 of the present invention, since a second low melting point Al layer is formed between the Fe-based metal member and the high melting point Al layer in the Fe-based metal / Al clad material, the Fe-based metal member and the high melting point Al layer are surely joined by the second low melting point Al layer. Also, after joining, an Al intermediate layer is formed with a sufficient thickness between the Fe-based compound layer and the ceramics member, and the Al intermediate layer acts as a buffer layer, making it possible to further improve the reliability of thermal cycle.

[0019] The Fe-based metal / ceramics joined body of Aspect 7 of the present invention is an Fe-based metal / ceramics joined body in which an Fe-based metal member made of a metal containing Fe and a ceramics member are joined, and a Fe-based compound layer containing either one or both of an Fe-Al intermetallic compound and an Fe-based oxide is formed between the ceramics member and the Fe-based metal member.

[0020] In the Fe-based metal / ceramics joined body of Aspect 7 of the present invention, since a Fe-based compound layer containing either one or both of an Fe-Al intermetallic compound and an Fe-based oxide is formed between the ceramics member and the Fe-based metal member, at the joining interface, the joining material containing Al and the Fe-based metal have reacted sufficiently, and the ceramics member and the Fe-based metal member are joined with sufficient strength. Also, since there is almost no Ag or active metal present at the joining interface, even when used under high temperature and high humidity conditions, migration of Ag does not occur, and insulation can be ensured. Also, the joining interface is not hardened by the active metal, and cracking at the joining interface during thermal cycle loading can be suppressed.

[0021] In the Fe-based metal / ceramics joined body of Aspect 8 of the present invention, in the Fe-based metal / ceramics joined body of Aspect 7, an Al intermediate layer is formed between the ceramics member and the Fe-based compound layer.

[0022] In the Fe-based metal / ceramics joined body of Aspect 8 of the present invention, since an Al intermediate layer is formed between the ceramics member and the Fe-based compound layer, this Al intermediate layer acts as a buffer layer, and it becomes possible to further improve the reliability of thermal cycle.

[0023] The Fe-based metal / ceramics joined body of Aspect 9 of the present invention is characterized in that, in the Fe-based metal / ceramics joined body of Aspect 8, the Al intermediate layer has a structure in which a plurality of Al phases having different compositions are laminated.

[0024] In the Fe-based metal / ceramics joined body of Aspect 9 of the present invention, since the Al intermediate layer has a structure in which a plurality of Al phases having different compositions are laminated, the buffering effect by this Al intermediate layer is improved, and it becomes possible to further improve the reliability of thermal cycle.

[0025] The Fe-based metal / Al clad material of Aspect 10 of the present invention has a structure in which an Fe-based metal member made of a metal containing Fe and a low melting point Al layer are laminated and joined, and between the Fe-based metal member and the low melting point Al layer, an Fe-based compound layer containing either one or both of an Fe-Al intermetallic compound and an Fe-based oxide is formed.

[0026] According to the Fe-based metal / Al clad material of Aspect 10 of the present invention, since the Fe-based metal member and the low melting point Al layer are laminated and joined, by making the low melting point Al layer act as a brazing material, it becomes possible to join the ceramics member and the Fe-based metal / Al clad material. Furthermore, since an Fe-based compound layer containing either or both of an Fe-Al intermetallic compound and an Fe-based oxide is formed between the Fe-based metal member and the low-melting-point Al layer, the Fe-based metal member and the low-melting-point Al layer are sufficiently bonded together. Furthermore, because it contains Fe-based metal components, it exhibits excellent press-workability and can suppress the generation of burrs and other defects.

[0027] The Fe-based metal / Al clad material of embodiment 11 of the present invention is characterized in that, in the Fe-based metal / Al clad material of embodiment 10 of the present invention, a high-melting-point Al layer is formed between the Fe-based metal member and the low-melting-point Al layer, and the Fe-based compound layer is formed between the Fe-based metal member and the high-melting-point Al layer.

[0028] According to the Fe-based metal / Al clad material of embodiment 11 of the present invention, a high-melting-point Al layer is formed between the Fe-based metal member and the low-melting-point Al layer, so that an Al intermediate layer that acts as a buffer layer can be reliably formed after joining with the ceramic member. Furthermore, since the Fe-based compound layer is formed between the Fe-based metal member and the high-melting-point Al layer, the Fe-based metal member and the high-melting-point Al layer are sufficiently bonded together.

[0029] The Fe-based metal / Al clad material of embodiment 12 of the present invention is characterized in that, in the Fe-based metal / Al clad material of embodiment 11 of the present invention, a second low-melting-point Al layer is formed between the Fe-based metal member and the high-melting-point Al layer, and the Fe-based compound layer is formed between the Fe-based metal member and the second low-melting-point Al layer.

[0030] According to the Fe-based metal / Al clad material of embodiment 12 of the present invention, a second low-melting-point Al layer is formed between the Fe-based metal member and the high-melting-point Al layer, so that the Fe-based metal member and the high-melting-point Al layer are sufficiently bonded by this second low-melting-point Al layer. Furthermore, since the Fe-based compound layer is formed between the Fe-based metal member and the second low-melting-point Al layer, the Fe-based metal member and the second low-melting-point Al layer are sufficiently bonded together.

[0031] The Fe-based metal / Al clad material of embodiment 13 of the present invention has a structure in which an Fe-based metal member made of a metal containing Fe and a low-melting-point Al layer are laminated and joined, and is characterized in that no Fe-Al intermetallic compound is formed between the Fe-based metal member and the low-melting-point Al layer.

[0032] According to the Fe-based metal / Al clad material of embodiment 13 of the present invention, since the structure is such that an Fe-based metal member and a low-melting-point Al layer are laminated and joined, it is possible to join a ceramic member and an Fe-based metal / Al clad material by using the low-melting-point Al layer as a brazing material. Furthermore, since no Fe-Al intermetallic compound is formed between the Fe-based metal member and the low-melting-point Al layer, when press working is performed on this Fe-based metal / Al clad material, crack formation at the interface between the Fe-based metal member and the low-melting-point Al layer can be suppressed, and the thermal resistance in the lamination direction can be kept low.

[0033] The Fe-based metal / Al clad material of embodiment 14 of the present invention is characterized in that, in the Fe-based metal / Al clad material of embodiment 13 of the present invention, a high-melting-point Al layer is formed between the Fe-based metal member and the low-melting-point Al layer, and no Fe-Al intermetallic compound is formed between the Fe-based metal member and the high-melting-point Al layer.

[0034] According to the Fe-based metal / Al clad material of embodiment 14 of the present invention, a high-melting-point Al layer is formed between the Fe-based metal member and the low-melting-point Al layer, so that an Al intermediate layer that acts as a buffer layer can be reliably formed after joining with the ceramic member. Furthermore, since no Fe-Al intermetallic compound is formed between the Fe-based metal member and the high-melting-point Al layer, when press working is performed on this Fe-based metal / Al clad material, crack formation at the interface between the Fe-based metal member and the high-melting-point Al layer can be suppressed, and the thermal resistance in the lamination direction can be kept low.

[0035] The Fe-based metal / Al clad material of embodiment 15 of the present invention is characterized in that, in the Fe-based metal / Al clad material of embodiment 12 of the present invention, a second low-melting-point Al layer is formed between the Fe-based metal member and the high-melting-point Al layer, and no Fe-Al intermetallic compound is formed between the Fe-based metal member and the second low-melting-point Al layer.

[0036] According to the Fe-based metal / Al clad material of embodiment 15 of the present invention, a second low-melting-point Al layer is formed between the Fe-based metal member and the high-melting-point Al layer, so that the Fe-based metal member and the high-melting-point Al layer are sufficiently bonded by this second low-melting-point Al layer. Furthermore, since no Fe-Al intermetallic compound is formed between the Fe-based metal member and the second low-melting-point Al layer, when press working is performed on this Fe-based metal / Al clad material, crack formation at the interface between the Fe-based metal member and the second low-melting-point Al layer can be suppressed, and the thermal resistance in the lamination direction can be kept low. [Effects of the Invention]

[0037] According to the present invention, it is possible to provide a method for manufacturing an Fe-based metal / ceramic bond that does not undergo migration, has excellent insulating properties, and can suppress cracking when subjected to thermal cycling, as well as an Fe-based metal / ceramic bond and an Fe-based metal / Al clad material that can be suitably used in the method for manufacturing the Fe-based metal / ceramic bond. [Brief explanation of the drawing]

[0038] [Figure 1] This is a schematic diagram illustrating an Fe-based metal / ceramics joint according to a first embodiment of the present invention. [Figure 2] This is a flowchart of a method for manufacturing an Fe-based metal / ceramic bond according to the first embodiment of the present invention. [Figure 3] This is a schematic diagram illustrating a method for manufacturing an Fe-based metal / ceramic bond according to a first embodiment of the present invention. [Figure 4] This is a schematic diagram illustrating the bonding material used in a method for manufacturing an Fe-based metal / ceramic joint according to the first embodiment of the present invention. [Figure 5] This is a flowchart of a method for manufacturing an Fe-based metal / ceramic bond according to a second embodiment of the present invention. [Figure 6] This is a schematic diagram illustrating a method for manufacturing an Fe-based metal / ceramic joint according to a second embodiment of the present invention. [Figure 7] This is a schematic diagram illustrating the Fe-based metal / Al clad material used in the method for manufacturing an Fe-based metal / ceramic joint according to the second embodiment of the present invention. [Modes for carrying out the invention]

[0039] Embodiments of the present invention will be described below with reference to the attached drawings.

[0040] <First Embodiment> As shown in Figure 1, the Fe-based metal / ceramic joint 10 according to the first embodiment of the present invention has a structure in which a ceramic member 11 made of ceramics and an Fe-based metal member 12 made of a metal containing Fe are joined together. Examples of ceramics that make up the ceramic member 11 include alumina (Al2O3), zirconia-reinforced alumina (ZrO2-Al2O3), aluminum nitride (AlN), and silicon nitride (Si3N4). Examples of Fe-based metals that constitute the Fe-based metal component 12 include Invar (Fe-36 mass%Ni-0.7 mass%Mn), Kovar (53~55 mass%Fe-29~30 mass%Ni-16~17 mass%Co-1 mass%Cr), stainless steel, and the like.

[0041] Furthermore, an Fe-based compound layer 15 containing either an Fe-Al intermetallic compound or an Fe-based oxide, or both, is formed between the ceramic member 11 and the Fe-based metal member 12. In this embodiment, as shown in Figure 1(a), the structure may be such that only an Fe-based compound layer 15 is formed between the ceramic member 11 and the Fe-based metal member 12. Furthermore, as shown in Figures 1(b) to 1(d), an Al intermediate layer 16 may be formed between the Fe-based compound layer 15 and the ceramic member 11. The Al intermediate layer 16 may be a single layer, or it may be a structure in which multiple Al alloys of different compositions are stacked.

[0042] In this embodiment, the Fe-based compound layer 15 is composed of either an Fe-Al intermetallic compound or an Fe-based oxide, or both. This Fe-based compound layer 15 is formed by a reaction between the Fe-based metal member 12 and the bonding material 30, which will be described later. In this embodiment, there is no particular lower limit to the thickness of the Fe-based compound layer 15, but it is preferably 0.5 μm or more, and more preferably 5 μm or more. Also, there is no particular upper limit to the thickness of the Fe-based compound layer 15, but it is preferably 165 μm or less, and more preferably 80 μm or less.

[0043] Furthermore, in this embodiment, as shown in Figures 1(b) to (d), the Al intermediate layer 16 formed between the Fe-based compound layer 15 and the ceramic member 11 is formed by Al contained in the bonding material 30, which will be described later. In Figure 1(b), the Al intermediate layer 16 is shown to have a single-layer structure consisting of a single phase. In the Fe-based metal / ceramic bonded body 10 shown in Figure 1(b), there is no particular limit to the lower limit of the thickness of the Al intermediate layer 16, but it is preferably 10 μm or more, and more preferably 30 μm or more. On the other hand, there is no particular limit to the upper limit of the thickness of the Al intermediate layer 16, but it is preferably 0.3 mm or less, and more preferably 0.1 mm or less.

[0044] In Figure 1(c), the Al intermediate layer 16 has a two-layer structure in which two phases of different compositions are stacked: a first Al intermediate layer 16A on the ceramic member 11 side and a second Al intermediate layer 16B on the Fe-based compound layer 15 side. In this embodiment, the purity of Al in the second Al intermediate layer 16B is higher than that of the first Al intermediate layer 16A. In the Fe-based metal / ceramic bonded body 10 shown in Figure 1(c), there is no particular lower limit to the thickness of the first Al intermediate layer 16A, but it is preferably 1.0 μm or more, and more preferably 5.0 μm or more. On the other hand, there is no particular upper limit to the thickness of the first Al intermediate layer 16A, but it is preferably 100 μm or less, and more preferably 50 μm or less. Furthermore, there is no particular lower limit to the thickness of the second Al intermediate layer 16B, but it is preferably 10 μm or more, and more preferably 30 μm or more. Also, there is no particular upper limit to the thickness of the second Al intermediate layer 16B, but it is preferably 0.3 mm or less, and more preferably 0.1 mm or less.

[0045] In Figure 1(d), the Al intermediate layer 16 has a three-layer structure in which three phases of different compositions are laminated: a first Al intermediate layer 16A on the ceramic member 11 side, a second Al intermediate layer 16B laminated on the first Al intermediate layer 16A, and a third Al intermediate layer 16C on the Fe-based compound layer 15 side. In this embodiment, the purity of Al in the second Al intermediate layer 16B is higher than that of the first Al intermediate layer 16A and the third Al intermediate layer 16C. In the Fe-based metal / ceramic bonded body 10 shown in Figure 1(d), there are no particular restrictions on the lower limit of the thickness of the first Al intermediate layer 16A and the third Al intermediate layer 16C, but it is preferably 1.0 μm or more, and more preferably 5.0 μm or more. On the other hand, there are no particular restrictions on the upper limit of the thickness of the first Al intermediate layer 16A and the third Al intermediate layer 16C, but it is preferably 100 μm or less, and more preferably 50 μm or less. Furthermore, there is no particular lower limit to the thickness of the second Al intermediate layer 16B, but it is preferably 10 μm or more, and more preferably 30 μm or more. Also, there is no particular upper limit to the thickness of the second Al intermediate layer 16B, but it is preferably 0.3 mm or less, and more preferably 0.1 mm or less.

[0046] In this embodiment, it is preferable that the Ag content in the Fe-based compound layer 15 and the Al intermediate layer 16 formed between the ceramic member 11 and the Fe-based metal member 12 is 0.03 mass% or less, and more preferably 0.01 mass% or less. Furthermore, it is preferable that the total content of active metals (Ti, Zr, Hf) in the Fe-based compound layer 15 and the Al intermediate layer 16 be 0.03 mass% or less. It is more preferable that it be 0.01 mass% or less.

[0047] The method for manufacturing the Fe-based metal / ceramic bond 10 according to this embodiment will be described below with reference to Figures 2 to 4.

[0048] (Lamination process S01) First, a ceramic member 11 and an Fe-based metal member 12 are prepared, and as shown in Figure 3, a bonding material 30 is placed between the ceramic member 11 and the Fe-based metal member 12, and these are then stacked.

[0049] Here, the joining material 30 can be one of the structures shown in Figures 4(a) to (c). Note that in Figure 3, the joining material 30 shown in Figure 4(a) is used. The bonding material 30 shown in Figure 4(a) is composed solely of a low-melting-point Al layer 30A. In the bonding material 30 shown in Figure 4(a), the thickness of the bonding material 30 (low-melting-point Al layer 30A) is preferably in the range of 5.0 μm to 100 μm.

[0050] The bonding material 30 shown in Figure 4(b) has a structure in which a low-melting-point Al layer 30A and a high-melting-point Al layer 30B with a higher melting point than the low-melting-point Al layer 30A are laminated together. The low-melting-point Al layer 30A and the high-melting-point Al layer 30B may be laminated together as separate, independent layers, or they may be laminated and joined together. In the bonding material 30 shown in Figure 4(b), the thickness of the low-melting-point Al layer 30A is preferably in the range of 5.0 μm to 100 μm, and the thickness of the high-melting-point Al layer 30B is preferably in the range of 10 μm to 0.3 mm. In this lamination process S01, if the bonding material 30 shown in Figure 4(b) is used, the lamination will be carried out so that the low-melting-point Al layer 30A faces the ceramic member 11.

[0051] The bonding material 30 shown in Figure 4(c) has a structure in which a low-melting-point Al layer 30A and a second low-melting-point Al layer 30C are laminated with a high-melting-point Al layer 30B that has a higher melting point than the low-melting-point Al layer 30A and the second low-melting-point Al layer 30C. The low-melting-point Al layer 30A, the high-melting-point Al layer 30B, and the second low-melting-point Al layer 30C may be laminated separately or they may be laminated and joined together. In the bonding material 30 shown in Figure 4(c), the thickness of the low-melting-point Al layer 30A and the second low-melting-point Al layer 30C is preferably in the range of 5.0 μm to 100 μm, and the thickness of the high-melting-point Al layer 30B is preferably in the range of 10 μm to 0.3 mm. In this lamination process S01, when the bonding material 30 shown in Figure 4(c) is used, the lamination is carried out such that the low-melting-point Al layer 30A faces the ceramic member 11 side, and the second low-melting-point Al layer 30C faces the Fe-based metal member 12 side.

[0052] In this embodiment, it is preferable that the low-melting-point Al layer 30A (second low-melting-point Al layer 30C) is made of an Al alloy with a liquidus temperature of less than 640°C, and the high-melting-point Al layer 30B is made of Al or an Al alloy with a solidus temperature of 640°C or higher. Specifically, the low-melting-point Al layer 30A (second low-melting-point Al layer 30C) is preferably composed of an Al-Si alloy, Al-Cu alloy, Al-Mg alloy, etc. Furthermore, it is preferable that the high-melting-point Al layer 30B is composed of 4N-Al, A1050, A3003, etc., with a purity of 99.99 mass% or higher.

[0053] (Joining process S02) Next, the stacked ceramic members 11, bonding material 30, and Fe-based metal members 12 are pressed in the stacking direction and heated in a heating furnace under vacuum or an inert atmosphere to bond the ceramic members 11 and the Fe-based metal members 12. In this embodiment, it is preferable that the heating temperature in the joining process S02 be within the range of the solidus temperature of the low-melting-point Al layer 30A (second low-melting-point Al layer 30C) or less than 660°C. Furthermore, it is preferable that the holding time at the heating temperature is within the range of 15 minutes to 240 minutes. Furthermore, it is preferable that the pressurized load in the joining process S02 is within the range of 0.1 MPa to 3.0 MPa.

[0054] In this case, if the bonding material 30 shown in Figure 4(a) is used, then either an Fe-based compound layer 15 will be formed between the ceramic member 11 and the Fe-based metal member 12, as shown in Figure 1(a), or an Fe-based compound layer 15 and an Al intermediate layer 16 will be formed, as shown in Figure 1(b). In other words, if all of the molten low-melting-point Al layer 30A reacts with the Fe-based metal member 12 during the heating process S02, the result will be as shown in Figure 1(a), and only the Fe-based compound layer 15 will be formed between the ceramic member 11 and the Fe-based metal member 12. On the other hand, if a portion of the low-melting-point Al layer 30A remains unreacted with the Fe-based metal member 12, the reacted portion will become the Fe-based compound layer 15, and the unreacted portion will become the Al intermediate layer 16, as shown in Figure 1(b).

[0055] Furthermore, if the bonding material 30 shown in Figure 4(b) is used as the bonding material 30, an Fe-based compound layer 15 and an Al intermediate layer 16 will be formed between the Fe-based metal member 12 and the ceramic member 11, as shown in Figure 1(b) or Figure 1(c).

[0056] Here, if all of the low-melting-point Al layer 30A and high-melting-point Al layer 30B constituting the joining material 30 melt during heating in the joining process S02, a large amount of liquid phase is formed between the ceramic member 11 and the Fe-based metal member 12. As shown in Figure 1(b), the portion that reacts with the Fe-based metal member 12 becomes the Fe-based compound layer 15, and the unreacted portion becomes the Al intermediate layer 16, which has a single-layer structure consisting of a single phase.

[0057] On the other hand, if a portion of the low-melting-point Al layer 30A and the high-melting-point Al layer 30B constituting the joining material 30 melts during heating in the joining process S02, as shown in Figure 1(c), the portion of the high-melting-point Al layer 30B that melts and reacts with the Fe-based metal member 12 becomes the Fe-based compound layer 15, the remaining portion becomes the second Al intermediate layer 16B, and the low-melting-point Al layer 30A becomes the first Al intermediate layer 16A.

[0058] Furthermore, if the bonding material 30 shown in Figure 4(c) is used as the bonding material 30, an Fe-based compound layer 15 and an Al intermediate layer 16 will be formed between the Fe-based metal member 12 and the ceramic member 11, as shown in Figure 1(b) or Figure 1(d).

[0059] Here, if, during the heating process S02, all of the low-melting-point Al layer 30A, high-melting-point Al layer 30B, and second low-melting-point Al layer 30C constituting the joining material 30 melt, then, as shown in Figure 1(b), the portion that reacts with the Fe-based metal member 12 becomes the Fe-based compound layer 15, and the unreacted portion becomes a single-phase, single-layer Al intermediate layer 16.

[0060] On the other hand, if, during heating in the joining process S02, a portion of the low-melting-point Al layer 30A, the second low-melting-point Al layer 30C, and the high-melting-point Al layer 30B that constitute the joining material 30 melts, as shown in Figure 1(d), the portion of the molten low-melting-point Al layer 30A that reacts with the Fe-based metal member 12 becomes the Fe-based compound layer 15, the unreacted portion becomes the third Al intermediate layer 16C, the high-melting-point Al layer 30B becomes the second Al intermediate layer 16B, and the second low-melting-point Al layer 30C becomes the first Al intermediate layer 16A.

[0061] As described above, the Fe-based metal / ceramic bonded body 10 of this embodiment is manufactured by the lamination process S01 and the bonding process S02.

[0062] The manufacturing method for the Fe-based metal / ceramic bond 10 of this embodiment, configured as described above, includes a lamination step S01 in which a ceramic member 11 and an Fe-based metal member 12 are laminated via an Al-containing bonding material 30, and a bonding step S02 in which the laminated ceramic member 11, bonding material 30, and Fe-based metal member 12 are heated while being pressurized in the lamination direction to bond the ceramic member 11 and the Fe-based metal member 12. As a result, there is almost no Ag or active metal at the bonding interface. Therefore, even when used under high temperature and high humidity conditions, Ag migration does not occur, and insulating properties can be ensured. In addition, the bonding interface does not harden due to active metals, and cracks at the bonding interface during thermal cycling loads can be suppressed. Therefore, it becomes possible to manufacture an Fe-based metal / ceramic bond 10 with excellent insulating properties and thermal cycle reliability.

[0063] In this embodiment, the bonding material 30 has a structure in which a high-melting-point Al layer 30B and a low-melting-point Al layer 30A are laminated, as shown in Figure 4(b). When the low-melting-point Al layer 30A is laminated in the lamination process S01 so that it faces the ceramic member 11, the low-melting-point Al layer 30A functions as a brazing material, and the ceramic member 11 and the Fe-based metal member 12 can be reliably joined. Furthermore, after bonding, an Al intermediate layer 16 is formed between the ceramic member 11 and the Fe-based compound layer 15. This Al intermediate layer 16 acts as a buffer layer, further improving the reliability of the thermal cycle.

[0064] In this embodiment, as shown in Figure 4(c), the bonding material 30 has a structure in which a high-melting-point Al layer 30B, a low-melting-point Al layer 30A formed on one side of the high-melting-point Al layer 30B, and a second low-melting-point Al layer 30C formed on the other side of the high-melting-point Al layer 30B are laminated. If the lamination process S01 is configured such that the low-melting-point Al layer 30A faces the ceramic member 11 and the second low-melting-point Al layer 30C faces the Fe-based metal member 12, then the low-melting-point Al layer 30A and the second low-melting-point Al layer 30C function as brazing materials, enabling reliable bonding between the ceramic member 11 and the Fe-based metal member 12. Furthermore, after bonding, an Al intermediate layer 16 is formed between the ceramic member 11 and the Fe-based compound layer 15. This Al intermediate layer 16 acts as a buffer layer, further improving the reliability of the thermal cycle.

[0065] In the Fe-based metal / ceramic joint 10 of this embodiment, an Fe-based compound layer 15 containing either or both of an Fe-Al intermetallic compound and an Fe-based oxide is formed between the ceramic member 11 and the Fe-based metal member 12. As a result, the bonding material 30 containing Al and the Fe-based metal member 12 react sufficiently at the bonding interface, and the ceramic member 11 and the Fe-based metal member 12 are bonded with sufficient strength. Furthermore, because there is virtually no Ag or active metal present at the bonding interface, Ag migration does not occur even when used under high temperature and high humidity conditions, ensuring insulation. In addition, the bonding interface does not harden due to active metals, which suppresses cracking at the bonding interface during thermal cycling loads.

[0066] In this embodiment, as shown in Figures 1(b) to 1(d), when an Al intermediate layer 16 is formed between the ceramic member 11 and the Fe-based metal member 12, this Al intermediate layer 16 acts as a buffer layer, making it possible to further improve the reliability of the thermal cycle. Furthermore, in this embodiment, as shown in Figures 1(c) to 1(d), if the Al intermediate layer 16 has a structure in which multiple Al phases with different compositions are stacked, the buffering effect of the Al intermediate layer 16 is improved, and the reliability of the thermal cycle can be further improved.

[0067] <Second Embodiment> In the second embodiment of the present invention, a method for manufacturing an Fe-based metal / ceramic bond, an Fe-based metal / ceramic bond 10 having the structure shown in Figures 1(b) to (d) is manufactured, and the composition of the Fe-based metal / ceramic bond 10, including the ceramic member 11, Fe-based metal member 12, Fe-based compound layer 15, Al intermediate layer 16, etc., is the same as in the first embodiment.

[0068] A second embodiment of the present invention, a method for manufacturing an Fe-based metal / ceramic bond, will be described below with reference to Figures 5 to 7.

[0069] (Preparation process for Fe-based metal / Al-clad material S51) First, prepare Fe-based metal / Al clad material 50. As the Fe-based metal / Al clad material 50, for example, as shown in Figure 7(a), a structure in which an Fe-based metal member 12 and a low-melting-point Al layer 51 are laminated can be used. In the Fe-based metal / Al clad material 50 shown in Figure 7(a), the thickness of the low-melting-point Al layer 51 is preferably in the range of 5.0 μm to 100 μm.

[0070] Furthermore, the Fe-based metal / Al clad material 50 may have a structure in which an Fe-based metal member 12, a high-melting-point Al layer 52, and a low-melting-point Al layer 51 are laminated, as shown in Figure 7(b). In this case, an Fe-based compound layer 15 is formed between the Fe-based metal member 12 and the high-melting-point Al layer 52. In the Fe-based metal / Al clad material 50 shown in Figure 7(b), the thickness of the low-melting-point Al layer 51 is preferably in the range of 5.0 μm to 100 μm, and the thickness of the high-melting-point Al layer 52 is preferably in the range of 10 μm to 0.3 mm.

[0071] Furthermore, the Fe-based metal / Al clad material 50 may have a structure in which an Fe-based metal member 12, a second low-melting-point Al layer 53, a high-melting-point Al layer 52, and a low-melting-point Al layer 51 are laminated, as shown in Figure 7(c). In this case, an Fe-based compound layer 15 is formed between the Fe-based metal member 12 and the second low-melting-point Al layer 53. In the Fe-based metal / Al clad material 50 shown in Figure 7(c), the thickness of the low-melting-point Al layer 51 and the second low-melting-point Al layer 53 is preferably in the range of 5.0 μm to 100 μm, and the thickness of the high-melting-point Al layer 52 is preferably in the range of 10 μm to 0.3 mm.

[0072] The Fe-based metal / Al clad material 50 mentioned above can be manufactured as follows. For example, the Fe-based metal / Al clad material 50 shown in Figure 7(a) can be manufactured by laminating an Fe-based metal member 12 with an Al plate that forms a low-melting-point Al layer 51, and then heating it under pressure. Here, when laminating the Fe-based metal member 12 and the Al plate that will become the low-melting-point Al layer 51 and applying pressure and heating, the heating temperature is preferably in the range of 250°C to 600°C, and the holding time at the heating temperature is preferably in the range of 10 minutes to 30 minutes. It is preferable to perform the heat treatment in air or an inert atmosphere. Furthermore, it is preferable that the pressing load in the lamination direction is in the range of 0.6 MPa to 5 MPa.

[0073] Furthermore, if the heating temperature is within the range of 250°C to 350°C, the formation of Fe-Al intermetallic compounds between the Fe-based metal member 12 and the low-melting-point Al layer 51 is suppressed. On the other hand, when the heating temperature is set within the range of over 350°C and under 600°C, the formation of Fe-Al intermetallic compounds between the Fe-based metal member 12 and the low-melting-point Al layer 51 is promoted.

[0074] Furthermore, it is also possible to manufacture the product by rolling a laminated structure consisting of an Fe-based metal component 12 and an Al plate forming a low-melting-point Al layer 51.

[0075] The Fe-based metal / Al clad material 50 shown in Figure 7(b) can be manufactured by laminating an Fe-based metal member 12 with an Al plate that forms a high-melting-point Al layer 52 and an Al plate that forms a low-melting-point Al layer 51, and then heating it under pressure. Here, the conditions for manufacturing the clad material and the formation of Fe-Al intermetallic compounds are the same as those for the clad material shown in Figure 7(a) above.

[0076] Alternatively, a laminate of a high-melting-point Al layer 52 and a low-melting-point Al layer 51 can be manufactured by stacking an Al plate that will become a high-melting-point Al layer 52 and an Al plate that will become a low-melting-point Al layer 51 and heating them under pressure, and then stacking an Fe-based metal member 12 on the resulting laminate and heating it under pressure. Here, the conditions for manufacturing the clad material and the formation of Fe-Al intermetallic compounds are the same as those for the clad material shown in Figure 7(a) above.

[0077] Furthermore, it is also possible to manufacture the product by rolling a laminated structure consisting of an Fe-based metal member 12, an Al plate forming a high-melting-point Al layer 52, and an Al plate forming a low-melting-point Al layer 51.

[0078] The Fe-based metal / Al clad material 50 shown in Figure 7(c) can be manufactured by laminating an Fe-based metal member 12 with an Al plate that forms the second low-melting-point Al layer 53, an Al plate that forms the high-melting-point Al layer 52, and an Al plate that forms the low-melting-point Al layer 51, and then heating it under pressure. Here, the conditions for manufacturing the clad material and the formation of Fe-Al intermetallic compounds are the same as those for the clad material shown in Figure 7(a) above.

[0079] Furthermore, a laminate of the second low-melting-point Al layer 53, the high-melting-point Al layer 52, and the low-melting-point Al layer 51 can be manufactured by stacking an Al plate to form the second low-melting-point Al layer 53, an Al plate to form the high-melting-point Al layer 52, and an Al plate to form the low-melting-point Al layer 51, and heating them under pressure. Subsequently, the Fe-based metal member 12 can be stacked on the resulting laminate and heated under pressure to manufacture the product. Here, the conditions for manufacturing the clad material and the formation of Fe-Al intermetallic compounds are the same as those for the clad material shown in Figure 7(a) above.

[0080] Furthermore, it is also possible to manufacture the product by rolling a laminated structure consisting of an Fe-based metal member 12, an Al plate forming a second low-melting-point Al layer 53, an Al plate forming a high-melting-point Al layer 52, and an Al plate forming a low-melting-point Al layer 51.

[0081] (Lamination process S52) Next, a ceramic member 11 is prepared, and as shown in Figure 6, an Fe-based metal / Al clad material 50 is laminated on the ceramic member 11. Note that in Figure 6, the Fe-based metal / Al clad material 50 shown in Figure 7(b) is used. In the lamination process S52, the Fe-based metal / Al clad material 50 is laminated such that the low-melting-point Al layer 51 faces the ceramic member 11.

[0082] (Joining process S53) Next, the stacked ceramic members 11 and Fe-based metal / Al clad material 50 are pressed in the stacking direction and heated in a heating furnace under vacuum or an inert atmosphere to bond the ceramic members 11 and the Fe-based metal / Al clad material 50. In this embodiment, it is preferable that the heating temperature in the joining process S53 be within the range of the solidus temperature of the low-melting-point Al layer 30A (second low-melting-point Al layer 30C) or less than 660°C. Furthermore, it is preferable that the holding time at the heating temperature is within the range of 15 minutes to 240 minutes. Furthermore, it is preferable that the pressurized load in the joining process S53 is within the range of 0.1 MPa to 3.0 MPa.

[0083] As described above, the Fe-based metal / Al clad material preparation step S51, the lamination step S52, and the joining step S53 are used to manufacture the Fe-based metal / ceramics bonded body 10 of this embodiment.

[0084] The manufacturing method for the Fe-based metal / ceramics joint 10 of this embodiment, which has the above configuration, includes an Fe-based metal / Al clad material preparation step S51 for preparing the Fe-based metal / Al clad material 50, and in the lamination step S52, the ceramic member 11 and the Fe-based metal / Al clad material 50 are laminated such that the low-melting-point Al layer 51 faces the ceramic member 11, so that the low-melting-point Al layer 51 acts as a brazing material, making it possible to join the Fe-based metal / Al clad material 50 and the ceramic member 11. Furthermore, because there is virtually no Ag or active metal present at the bonding interface, Ag migration does not occur even when used under high temperature and high humidity conditions, ensuring insulation. In addition, the bonding interface does not harden due to active metals, which suppresses cracking at the bonding interface during thermal cycling loads. Therefore, it becomes possible to manufacture an Fe-based metal / ceramic bond 10 with excellent insulating properties and thermal cycle reliability.

[0085] In this embodiment, when the Fe-based metal / Al clad material 50 has a high-melting-point Al layer 52 formed between the Fe-based metal member 12 and the low-melting-point Al layer 51, after joining, an Al intermediate layer 16 is formed with sufficient thickness between the Fe-based compound layer 15 and the ceramic member 11. The Al intermediate layer 16 acts as a buffer layer, further improving the reliability of the thermal cycle.

[0086] In this embodiment, when a second low-melting-point Al layer 53 is formed between the Fe-based metal member 12 and the high-melting-point Al layer 52 of the Fe-based metal / Al clad material 50, the Fe-based metal member 12 and the high-melting-point Al layer 52 are reliably joined by the second low-melting-point Al layer 53. Furthermore, after joining, an Al intermediate layer 16 is formed between the Fe-based metal member 12 and the ceramic member 11, and the Al intermediate layer 16 acts as a buffer layer, making it possible to further improve the reliability of the thermal cycle.

[0087] Although embodiments of the present invention have been described above, the present invention is not limited thereto and can be modified as appropriate without departing from the technical spirit of the invention. [Examples]

[0088] The results of the verification experiments conducted to confirm the effects of the present invention are described below.

[0089] (Example 1) Fe-based metal plates (37mm x 37mm, thickness as indicated in the table) and ceramic plates (40mm x 40mm, thickness as indicated in the table) as shown in Tables 1 and 2 were prepared. Then, the bonding material (37 mm x 37 mm, thickness as indicated in the table) described in Tables 1 and 2 was placed between the Fe-based metal plate and the ceramic plate to obtain a laminate. Next, an Fe-based metal plate and a ceramic plate were joined under the conditions shown in Tables 3 and 4 to obtain an Fe-based metal / ceramic bond. A circuit pattern with a pattern spacing of 0.8 mm was formed on the Fe-based metal plate.

[0090] The obtained Fe-based metal / ceramic bonded structures were evaluated for the thickness of the Fe-based compound layer, migration resistance, and thermal cycling reliability. The evaluation results are shown in Tables 3 and 4. The details of the materials used for the bonding material and ceramic plates are as follows. Note that all compositions are expressed in mass percent.

[0091] [A2024] Si: less than 0.50%, Fe: less than 0.50%, Cu: 3.8% to 4.9%, Mn: 0.30% to 0.9%, Mg: 1.2% to 1.8%, Cr: less than 0.1%, Zn: less than 0.25%, Ti: less than 0.15%, Al: residue [A2419] Si: less than 0.15%, Fe: less than 0.18%, Cu: 5.8% to 6.8%, Mn: 0.20% to 0.40%, Mg: less than 0.02%, Zn: less than 0.1%, Ti: 0.02% to 0.10%, V: 0.05% to 0.15%, Zr: 0.10% to 0.25%, Al: residue

[0092] [A4008] Si: 6.5% to 7.5%, Fe: 0.09% to 0.05%, Mn: 0.05% to 0.05%, Mg: 0.30% to 0.45%, Zn: 0.05% to 0.05%, Ti: 0.04% to 0.15%, Al: residue [A4013] Si: 3.5% to 4.5%, Fe: 0.35% to 0.20%, Cu: 0.05% to 0.03%, Mn: 0.03%, Mg: 0.05% to 0.20%, Zn: 0.05%, Ti: 0.02%, Bi: 0.6% to 1.5%, Al: residue [A4032] Si: 11.0% to 13.0%, Fe: 1.0% or less, Cu: 0.50% to 1.3% or less, Mg: 0.8% to 1.3% or less, Cr: 0.1% or less, Ni: 0.50% to 1.3% or less, Zn: 0.25% or less, Al: residue [A4043] Si: 4.5% to 6.0%, Fe: 0.8% to 0.3%, Mn: 0.05% to 0.05%, Mg: 0.05% to 0.1%, Ti: 0.2% to 0.2%, Al: residue [A4045] Si: 9.0% to 11.0%, Fe: 0.8% or less, Cu: 0.3% or less, Mn: 0.05% or less, Mg: 0.05% or less, Zn: 0.1% or less, Ti: 0.2% or less, Al: residue

[0093] [A5052] Si: 0.25% or less, Fe: 0.40% or less, Cu: 0.10% or less, Mn: 0.10% or less, Mg: 2.2% or more and 2.8% or less, Cr: 0.15% or more and 0.35% or less, Zn: 0.10% or less, Al: balance [A5056] Si: 0.30% or less, Fe: 0.40% or less, Cu: 0.10% or less, Mn: 0.05% or more and 0.20% or less, Mg: 4.5% or more and 5.6% or less, Cr: 0.05% or more and 0.20% or less, Zn: 0.10% or less, Al: balance [A7075] Si: 0.40% or less, Fe: 0.50% or less, Cu: 1.2% or more and 2.0% or less, Mn: 0.30% or less, Mg: 2.1% or more and 2.9% or less, Cr: 0.18% or more and 0.28% or less, Zn: 5.1% or more and 6.1% or less, Ti: 0.20% or less, Al: balance

[0094] [A1050] Si: 0.25% or less, Fe: 0.40% or less, Cu: 0.05% or less, Mn: 0.05% or less, Mg: 0.05% or less, Zn: 0.05% or less, Ti: 0.03% or less, V: 0.05% or less, Al: 99.5% or more [A3003] Si: 0.6% or less, Fe: 0.7% or less, Cu: 0.05% or more and 0.20% or less, Mn: 1.0% or more and 1.5% or less, Zn: 0.1% or less, Al: balance [Al2O3-ZrO2] Al2O3: 80%, ZrO2: 20%

[0095] (Thickness of the Fe-based compound layer) Using EPMA, elemental mapping was acquired for five fields of view, each with a 200 μm square cross-section including the junction interface, at an acceleration voltage of 15.0 kV. During this process, the elemental mapping was performed so that the junction interface and the field of view were horizontal. The area (μm²) of the region where the mappings of Fe and O overlap, and the region where, when Fe and Al together are considered to be 100 mass%, Fe is 13-61 mass% and Al is 39-87 mass%. 2The thickness of the Fe-based compound layer (μm) was defined as the ratio of the junction interface to the field of view width (μm) in the horizontal direction.

[0096] (Migration test) After being left for 1000 hours under conditions of 60°C, 95% RH, and DC 50V, the electrical resistance between circuits (with a pattern spacing of 0.8 mm) was measured. Resistance value is 1 × 10 6 If the resistance becomes less than Ω, it is judged that a short circuit has occurred due to Ag migration and evaluated as "×", and the resistance value is 1 × 10 6 Cases exceeding Ω were evaluated as "○".

[0097] (Initial joining rate) Using a ultrasonic flaw detection (SAT) device, SAT images were acquired of the bonding interface between the Fe-based metal plate and the ceramic plate, and the bonding area ratio was calculated using image analysis.

[0098] (Bonding rate after thermal cycling test) A thermal cycle of -40°C for 5 minutes and 125°C for 5 minutes was repeated 2000 times using a thermal testing machine. Subsequently, ultrasonic testing (SAT) was used to acquire SAT images of the bonding interface between the Fe-based metal plate and the ceramic plate, and the bonding area ratio was calculated using image analysis.

[0099] [Table 1]

[0100] [Table 2]

[0101] [Table 3]

[0102] [Table 4]

[0103] In Comparative Example 1, since an adhesive containing Ag was used to bond the Fe-based metal member and the ceramic member, Ag was present at the bonding interface, resulting in a migration resistance of "×". In Comparative Example 2, since the Fe-based metal member and the ceramic member were joined using a bonding material containing Ag and the active metal Ti, Ag was present at the bonding interface, resulting in a "×" rating for migration resistance. Furthermore, the bonding ratio decreased significantly after the thermal cycle, indicating poor thermal cycle reliability.

[0104] In contrast, in Examples 1 to 29 of the present invention, a bonding material having a low-melting-point Al layer is used to bond an Fe-based metal member and a ceramic member. As a result, no Ag or active metals are present at the bonding interface, migration resistance is "○", and the bonding ratio does not decrease significantly after the thermal cycle, demonstrating excellent thermal cycle reliability.

[0105] (Example 2) Fe-based metal plates (37mm x 37mm, thickness as indicated in the table) and bonding materials (37mm x 37mm, thickness as indicated in the table) as described in Tables 5 and 6 were prepared. These Fe-based metal sheets and bonding material were rolled to a thickness of 0.8 to 0.9 times the thickness of the laminated material, and then heat-treated in an air atmosphere at a heating temperature of 400°C for a holding time of 20 minutes to obtain an Fe-based metal / Al clad material. Then, the aforementioned Fe-based metal / Al clad material was laminated onto the ceramic plates (40mm x 40mm, thickness as indicated in the table) described in Tables 5 and 6. Next, an Fe-based metal / Al clad material and a ceramic plate were joined under the conditions shown in Tables 7 and 8 to obtain an Fe-based metal / ceramic bond. A circuit pattern with a pattern spacing of 0.8 mm was formed on the Fe-based metal plate.

[0106] The obtained Fe-based metal / ceramic bond was evaluated for the thickness of the Fe-based compound layer, migration resistance, and thermal cycling reliability using the same method as in Example 1. The evaluation results are shown in Tables 7 and 8.

[0107] [Table 5]

[0108] [Table 6]

[0109] [Table 7]

[0110] [Table 8]

[0111] In Examples 51-79 of the present invention, a structure is formed in which an Fe-based metal member and a low-melting-point Al layer are laminated and joined together. An Fe-based compound layer is formed between the Fe-based metal member and the low-melting-point Al layer. This Fe-based metal / Al clad material is joined to a ceramic member, and no Ag or active metals are present at the bonding interface, resulting in migration resistance of "○". Furthermore, the bonding ratio does not decrease significantly after thermal cycling, demonstrating excellent thermal cycling reliability.

[0112] (Example 3) Fe-based metal plates (37mm x 37mm, thickness as indicated in the table) and bonding materials (37mm x 37mm, thickness as indicated in the table) as listed in Table 9 were prepared. These Fe-based metal plates and bonding materials were laminated, pressurized at 5 MPa in the lamination direction under an atmospheric environment, and heated under the conditions described in Table 9 to obtain an Fe-based metal / Al clad material.

[0113] For the obtained Fe-based metal / Al clad material, the presence or absence of Fe-Al intermetallic compounds between the Fe-based metal plate and the second low-melting-point aluminum layer was evaluated as follows. The evaluation results are shown in Table 9.

[0114] (Presence or absence of Fe-Al intermetallic compounds) Elemental mapping was obtained using EPMA in the same manner as in Example 1. If a region where the mappings of Fe and O overlapped, or a region where Fe was 13-61 mass% and Al was 39-87 mass% when Fe and Al were combined to 100 mass%, the presence of an Fe-Al intermetallic compound was considered.

[0115] Then, the aforementioned Fe-based metal / Al clad material was laminated onto the ceramic plate (40 mm x 40 mm, thickness as shown in Table 10). The Fe-based metal / Al clad material and the ceramic plate were joined under the conditions shown in Table 10 to obtain an Fe-based metal / ceramic bond. A circuit pattern with a pattern spacing of 0.8 mm was formed on the Fe-based metal plate. The obtained Fe-based metal / ceramic bond was evaluated for the thickness of the Fe-based compound layer, migration resistance, and thermal cycling reliability using the same method as in Example 1. The thermal resistance ratio was also evaluated as follows. The evaluation results are shown in Table 10.

[0116] (thermal resistance) For the Fe-based metal-ceramic bond, TO-247 (Infineon Technologies AG) was brought into contact with the surface of the Fe-based metal plate via grease (100 μm thick). The ceramic plate and the cooler were also brought into contact via grease (100 μm thick). Then, a pressure of 500 g was applied to ensure tight contact between the TO-247 and the cooler. Using a T3ster (Mentor Graphics) device, a TO-247 tube was heated with 40W of power, and its thermal resistance was measured according to the method described in JESD51-14. In this example, the values ​​are listed in the table as a ratio with the thermal resistance of Example 82 of the present invention set to 1.

[0117] [Table 9]

[0118] [Table 10]

[0119] As shown in Table 9, in Example 81 of the present invention, where the heating temperature during lamination, pressurization, and heating of the Fe-based metal plate and bonding material was set to 400°C, an Fe-Al intermetallic compound was present between the Fe-based metal plate and the second low-melting-point aluminum layer. On the other hand, in Examples 82 to 86 of the present invention, where the heating temperature when laminating the Fe-based metal plate and the bonding material and applying pressure and heating was 350°C or lower, no Fe-Al intermetallic compound was present between the Fe-based metal plate and the second low-melting-point aluminum layer.

[0120] Furthermore, in the Fe-based metal / ceramic bonded bodies formed by joining Fe-based metal / Al clad material and ceramic plates, Examples 81-86 of the present invention showed high initial bonding rates and bonding rates after thermal cycling tests, demonstrating excellent thermal cycling reliability. Furthermore, in Example 81 of the present invention, where an Fe-Al intermetallic compound was present between the Fe-based metal plate and the second low-melting-point aluminum layer, it was confirmed that the thermal resistance ratio was higher compared to Examples 82-86 of the present invention, where no Fe-Al intermetallic compound was present between the Fe-based metal plate and the second low-melting-point aluminum layer.

[0121] Based on the results of the above verification experiments, it has been confirmed that, according to the present invention, it is possible to provide a method for manufacturing an Fe-based metal / ceramic bond, an Fe-based metal / ceramic bond, and an Fe-based metal / Al clad material that can be suitably used in the method for manufacturing an Fe-based metal / ceramic bond, which have no migration occurrence, excellent insulating properties, and can suppress cracking when subjected to thermal cycling. [Explanation of Symbols]

[0122] 10 Fe-based metal / ceramic bond 11 Ceramic components 12 Fe-based metal components 15 Fe-based compound layer 16 Al interlayer 30 Bonding material 50 Fe-based metal / Al clad material

Claims

1. A method for manufacturing an Fe-based metal / ceramic joint, in which an Fe-based metal member made of a metal containing Fe and a ceramic member are joined together, A lamination step of laminating the ceramic member and the Fe-based metal member via a bonding material containing Al, A bonding step in which the laminated ceramic members, the bonding material, and the Fe-based metal members are heated while being pressurized in the lamination direction to bond the ceramic members and the Fe-based metal members, A method for manufacturing an Fe-based metal / ceramic bond, characterized by comprising the following:

2. The aforementioned bonding material has a structure in which a high-melting-point Al layer and a low-melting-point Al layer are laminated together. The method for manufacturing an Fe-based metal / ceramic bond according to claim 1, characterized in that in the lamination step, the low-melting-point Al layer is laminated so as to face the ceramic member side.

3. The bonding material comprises a high-melting-point Al layer, a low-melting-point Al layer formed on one side of the high-melting-point Al layer, and a second low-melting-point Al layer formed on the other side of the high-melting-point Al layer. The method for manufacturing an Fe-based metal / ceramic bond according to claim 1, characterized in that, in the lamination step, the low-melting-point Al layer faces the ceramic member side, and the second low-melting-point Al layer faces the Fe-based metal member side.

4. A method for manufacturing an Fe-based metal / ceramic joint, in which an Fe-based metal member made of a metal containing Fe and a ceramic member are joined together, An Fe-based metal / Al clad material preparation step is performed to prepare an Fe-based metal / Al clad material in which an Fe-based metal component made of a metal containing Fe and a low-melting-point Al layer are laminated and joined together, A lamination step of laminating the ceramic member and the Fe-based metal / Al clad material, A bonding step is performed in which the laminated ceramic members and the Fe-based metal / Al clad material are heated while being pressurized in the lamination direction to bond the ceramic members and the Fe-based metal / Al clad material, It is equipped with, A method for manufacturing an Fe-based metal / ceramic bond, characterized in that, in the lamination step, the low-melting-point Al layer is laminated so as to face the ceramic member side.

5. The method for manufacturing an Fe-based metal / ceramics bond according to claim 4, characterized in that the Fe-based metal / Al clad material has a high-melting-point Al layer formed between the Fe-based metal member and the low-melting-point Al layer.

6. The method for manufacturing an Fe-based metal / ceramics bond according to claim 5, characterized in that the Fe-based metal / Al clad material has a second low-melting-point Al layer formed between the Fe-based metal member and the high-melting-point Al layer.

7. An Fe-based metal / ceramic joint is formed by joining an Fe-based metal member made of a metal containing Fe to a ceramic member, An Fe-based metal / ceramic bond is characterized in that an Fe-based compound layer containing either or both of an Fe-Al intermetallic compound and an Fe-based oxide is formed between the ceramic member and the Fe-based metal member.

8. The Fe-based metal / ceramic bond according to claim 7, characterized in that an Al intermediate layer is formed between the ceramic member and the Fe-based compound layer.

9. The Fe-based metal / ceramic bond according to claim 8, characterized in that the Al intermediate layer has a structure in which multiple Al phases of different compositions are stacked.

10. An Fe-based metal / Al clad material characterized by having a structure in which an Fe-based metal member made of a metal containing Fe and a low-melting-point Al layer are laminated and joined, and an Fe-based compound layer containing either or both of an Fe-Al intermetallic compound and an Fe-based oxide is formed between the Fe-based metal member and the low-melting-point Al layer.

11. The Fe-based metal / Al clad material according to claim 10, characterized in that a high-melting-point Al layer is formed between the Fe-based metal member and the low-melting-point Al layer, and the Fe-based compound layer is formed between the Fe-based metal member and the high-melting-point Al layer.

12. The Fe-based metal / Al clad material according to claim 11, characterized in that a second low-melting-point Al layer is formed between the Fe-based metal member and the high-melting-point Al layer, and the Fe-based compound layer is formed between the Fe-based metal member and the second low-melting-point Al layer.

13. An Fe-based metal / Al clad material characterized by having a structure in which an Fe-based metal member made of a metal containing Fe and a low-melting-point Al layer are laminated and joined, and no Fe-Al intermetallic compound is formed between the Fe-based metal member and the low-melting-point Al layer.

14. The Fe-based metal / Al clad material according to claim 13, characterized in that a high-melting-point Al layer is formed between the Fe-based metal member and the low-melting-point Al layer, and no Fe-Al intermetallic compound is formed between the Fe-based metal member and the high-melting-point Al layer.

15. The Fe-based metal / Al clad material according to claim 14, characterized in that a second low-melting-point Al layer is formed between the Fe-based metal member and the high-melting-point Al layer, and no Fe-Al intermetallic compound is formed between the Fe-based metal member and the second low-melting-point Al layer.

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