Joint, manufacturing method thereof, and electrode-embedded member

Abstract

To provide a joined body which can suppress erosion and contamination of a joined surface, has strong bond strength, and has thick metal member, a method for manufacturing the same, and an electrode embedding member.SOLUTION: There is provided a joined body 10 of a ceramic member 20 containing AIN as a main component and a metal member 30 composed of high melting point metal having a melting point of 2,000°C or higher, wherein the ceramic member 20 is joined to at least one main surface 32 of the metal member 30, the metal member 30 has a maximum thickness in a direction perpendicular to the one main surface 32 of the metal member 30 of 1 mm or more, and three-point flexural strength of a joint interface of the joined body 10 of the ceramic member 20 and the metal member 30 is 70 MPa or more.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a bonded body, a method for producing the same, and an electrode-embedding member. [Background technology]

[0002] AlN components used in semiconductor manufacturing equipment are sometimes joined to metal components to add various functions.

[0003] Patent Document 1 discloses a bonded assembly in which an aluminum nitride member and a metal member are bonded with an aluminum brazing material, and a semiconductor holder. A preferred embodiment is disclosed in which the aluminum nitride member is a semiconductor holder having a mounting surface for mounting a semiconductor wafer, and the metal member is a heat transfer member for transferring heat between the semiconductor holder and the outside. The document also discloses examples of heat transfer members made of tungsten, molybdenum, copper, or alloys thereof. These metal members function as heat sinks and have a certain thickness.

[0004] Furthermore, Patent Document 2 discloses an aluminum nitride joined body having a relatively thick and highly conductive sintered metal layer incorporated therein, which minimizes warpage and has a high bonding strength between the sintered metal layer and the substrate, and is suitable for use as an electrode-embedded member, and a method for manufacturing the same. The aluminum nitride joined body has an aluminum nitride sintered body having a sintered metal layer made of tungsten or molybdenum and having a thickness of 15 to 100 μm formed on at least a portion of the bonding surface, and the sheet resistance of the sintered metal layer is 1 Ω / □ or less and the warpage of the sintered metal layer is 100 μm / 100 mm or less, with the aim of providing such an aluminum nitride joined body and a method for manufacturing the same. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 9-249465 [Patent Document 2] Japanese Patent Application Laid-Open No. 2005-159334 [Patent Document 3] Japanese Patent Application Publication No. 5-246769 [Patent Document 4] Japanese Patent Application Publication No. 62-78167 [Non-patent literature]

[0006] [Non-Patent Document 1] Journal of the Japan Institute of Metals, Vol. 45, No. 2 (1981), pp. 184-189 Summary of the Invention [Problem to be solved by the invention]

[0007] AlN ceramics used in semiconductor manufacturing processes are sometimes integrated with high-melting-point metals with melting points of 2000°C or higher, which are used for heat sinks, etc. To do this, the high-melting-point metal needs to be thicker than a certain amount, but such a structure cannot be achieved with a sintered metal layer such as that described in Patent Document 2.

[0008] According to Non-Patent Document 1, it has been said that it is difficult to produce a bonded body because AlN and high-melting-point metals do not react without a bonding material. Therefore, conventionally, a bonded body of AlN ceramic and high-melting-point metal has been produced by joining them with a brazing material or the like at the bonding interface (Patent Documents 1, 3, and 4).

[0009] However, when these bonded bodies are used in semiconductor manufacturing processes, there are concerns about erosion of the brazing material that forms the bonding layer and contamination from the bonding layer in the methods of Patent Documents 1, 3, and 4. Therefore, there has been a demand for an AlN-high melting point metal bonded body that is a bonded body of AlN ceramic and a thick high melting point metal and that reduces the risk of contamination and erosion from the bonding material.

[0010] The present invention has been made in view of the above circumstances, and aims to provide a bonded body that can suppress erosion and contamination of the bonding surface, has high bonding strength, and has thick metal members, a manufacturing method thereof, and an electrode-embedded member. [Means for solving the problem]

[0011] (1) In order to achieve the above object, the present invention provides a joined body of ceramic members mainly composed of AlN and metal members made of a high-melting-point metal having a melting point of 2000°C or higher, wherein the ceramic members are: one main surface of the ceramic member and one main surface of the metal member are in direct contact with each other, The ceramic member is bonded to at least one of the main surfaces of the metal member, and the metal member has a maximum thickness of 1 mm or more in a direction perpendicular to the one of the main surfaces of the metal member, and the bonded body of the ceramic member and the metal member has a three-point bending strength of 70 MPa or more at the bonded interface.

[0012] In this way, the high three-point bending strength of the bonded interface of a bonded body made of a ceramic member primarily composed of AlN and a metal member made of a high-melting-point metal allows for a bonded body that suppresses erosion and contamination of the bonded surface. Furthermore, the thick metal member allows for various applications, such as using the metal member as a heat sink or increasing the strength and dimensional accuracy of the ceramic member. If the maximum thickness of the metal member is less than 1 mm, the effect of improving dimensional accuracy is not fully realized, so a thickness of 1 mm or more is preferable.

[0013] (2) In the joined body of the present invention, the ceramic member contains a second phase made of a metal oxide.

[0014] In this way, since the ceramic member contains a second phase consisting of a metal oxide, the ceramic member and the metal member are joined via this, increasing the joining strength between the ceramic member and the metal member and improving the reliability of the joined body.

[0015] (3) In the joined body of the present invention, the ceramic member contains a metal of Group 4, and the metal member has the metal of Group 4 diffused therein.

[0016] In this way, the ceramic member contains a Group 4 metal and the Group 4 metal is diffused into the metal member, thereby increasing the bonding strength between the ceramic member and the metal member and increasing the reliability of the bonded body.

[0017] (4) In the joined body of the present invention, the relative density of the metal members is 95% or more and 99.9% or less.

[0018] In this way, by making the relative density of the metal member 95% or more and 99.9% or less, internal residual stress is alleviated, and it is possible to improve dimensional accuracy and processing accuracy.

[0019] (5) The bonded body of the present invention is characterized in that a ceramic member containing AlN as a main component is further bonded to the other main surface of the metal member opposite to the one main surface of the metal member.

[0020] In this way, by joining ceramic members to both main surfaces of a metal member, the range of uses of the joined body is further expanded.

[0021] (6) The electrode-embedding member of the present invention is characterized by comprising the joined body according to any one of (1) to (4) above and an electrode embedded in a ceramic member of the joined body.

[0022] Since AlN has high thermal conductivity and high insulating properties, an electrode-embedded component in which an electrode is embedded in a ceramic component of a bonded body made of a ceramic component and a metal component made of a high-melting-point metal can be used as a heater module with excellent thermal conductivity.

[0023] (7) The method for manufacturing a bonded body of the present invention is also a method for manufacturing a bonded body by using a ceramic member mainly composed of AlN and a high-melting-point metal having a melting point of 2000°C or higher. Moa step of granulating AlN raw material powder to produce a granulated powder; a step of preparing a plate-shaped high-melting point metal porous body made of the high-melting point metal having a relative density of 40% to 90% and a thickness in the pressing direction of 1 mm or more after uniaxial pressure sintering in a direction perpendicular to a main surface; and a step of manufacturing a plate-shaped high-melting point metal porous body made of the high-melting point metal, the plate-shaped high-melting point metal porous body having a relative density of 40% to 90% and a thickness in the pressing direction of 1 mm or more after uniaxial pressure sintering in a direction perpendicular to a main surface. The granulated powder or a compact formed from the granulated powder is in direct contact with the main surface of the plate-shaped high-melting point porous metal body, and The method is characterized by including the steps of: stacking the plate-shaped high-melting-point porous metal body on a carbon mold so that the main surface is perpendicular to the stacking direction; inserting a carbon punch into the carbon mold to form a laminate; and uniaxially pressurizing and firing the laminate at a temperature of 1800°C or higher.

[0024] This allows for the production of a bonded assembly consisting of a ceramic component primarily composed of AlN and a metal component made of a high-melting-point metal, with reduced erosion and contamination at the bonding surface. The thick metal component can be used for a variety of purposes, such as as a heat sink or to increase the strength and dimensional accuracy of the ceramic component.

[0025] (8) The method for manufacturing a joined body of the present invention is also a method for manufacturing a joined body by using a ceramic member mainly composed of AlN and a high-melting-point metal having a melting point of 2000°C or more. Mo a step of roughening a main surface to be joined of the plate-shaped high-melting-point metal having a thickness of 1 mm or more; a step of stacking the granulated powder or a compact formed from the granulated powder and the plate-shaped high-melting-point metal in a carbon mold so that the main surface of the plate-shaped high-melting-point metal contacts the granulated powder or the compact formed from the granulated powder perpendicular to the stacking direction; a step of inserting a carbon punch into the carbon mold to form a stack; and a step of uniaxially pressing and sintering the stack at a temperature of 1800°C or higher.

[0026] This allows for the production of a bonded assembly consisting of a ceramic component primarily composed of AlN and a metal component made of a high-melting-point metal, with reduced erosion and contamination at the bonding surface. The thick metal component can be used for a variety of purposes, such as as a heat sink or to increase the strength and dimensional accuracy of the ceramic component. [Effects of the Invention]

[0027] According to the present invention, a bonded body can be obtained in which erosion and contamination of the bonding surface between a ceramic member mainly composed of AlN and a metal member made of a high-melting-point metal is suppressed. Furthermore, the thick metal member can be used for various purposes, such as using the metal member as a heat sink or improving the strength and dimensional accuracy of the ceramic member. [Brief explanation of the drawings]

[0028] [Figure 1] 1 is a schematic cross-sectional view showing an example of a bonded body according to an embodiment of the present invention. [Figure 2] FIG. 10 is a schematic cross-sectional view showing a modified example of the bonded body according to the embodiment of the present invention. [Figure 3] 1 is a schematic cross-sectional view showing an example of an electrode-embedded member according to an embodiment of the present invention. [Figure 4] 1(a) to 1(e) are cross-sectional views each showing a schematic diagram of a step in the manufacturing process of a manufacturing method according to an embodiment of the present invention. [Figure 5] 1 is a photomicrograph of a cross section of a bonding interface of a bonded body of Example 1. DETAILED DESCRIPTION OF THE INVENTION

[0029] Next, an embodiment of the present invention will be described with reference to the drawings. To facilitate understanding of the description, the same reference numerals are used to designate the same components in the drawings, and duplicated descriptions will be omitted. Note that in the configuration diagrams, the size of each component is shown conceptually and does not necessarily represent the actual dimensional ratio.

[0030] [Embodiment] [Construction of the zygote] First, a bonded body according to an embodiment of the present invention will be described. FIG. 1 is a schematic cross-sectional view showing an example of a bonded body according to an embodiment of the present invention. A bonded body 10 according to an embodiment of the present invention is a bonded body of a ceramic member primarily composed of AlN and a metal member made of a high-melting-point metal having a melting point of 2000°C or higher. A ceramic member primarily composed of AlN refers to a member containing 90 wt% or more of AlN. A metal member made of a high-melting-point metal having a melting point of 2000°C or higher refers to a metal member having a purity of 99 wt% or higher, such as molybdenum (Mo), tungsten (W), or tantalum (Ta), which has a melting point of 2000°C or higher. This suppresses deformation of the metal member 30 even at temperatures during uniaxial pressure sintering. At the same time, a high-melting-point metal oxide having a relatively high melting point of 900°C or higher is formed at the interface between the AlN and the metal member 30, thereby suppressing deformation at the bonding interface between the AlN and the metal member 30.

[0031] In the joined body 10, the ceramic member 20 is joined to at least one main surface of the metal member 30. The metal member 30 preferably has a maximum diameter that is 50% or more of the maximum diameter of the ceramic member 20. The ceramic member 20 is preferably joined to the entire surface of one main surface 32 of the metal member 30. These characteristics allow the metal member 30 to be applied in various forms according to various uses. The ceramic member 20 is preferably joined directly to one main surface 32 of the metal member 30 without any other member interposed therebetween. This is because the use of another member interposed therebetween may reduce the joining strength.

[0032] The joined body 10 according to the embodiment of the present invention has a three-point bending strength of 70 MPa or more at the bonding interface of the joined body 10 of the ceramic members 20 and the metal members 30. Since the joined body 10 of the ceramic members 20 mainly composed of AlN and the metal members 30 made of a high-melting-point metal has a high three-point bending strength at the bonding interface, it is not necessary to use a brazing material or adhesive for bonding, and it is possible to obtain the joined body 10 in which erosion and contamination of the bonding surface are suppressed.

[0033] The metal member 30 has a maximum thickness of 1 mm or more in a direction perpendicular to one main surface 32 of the metal member 30. In this way, the metal member 30 having a large thickness can be used in a variety of applications, such as using the metal member 30 as a heat sink or heat spreader, or improving the strength and dimensional accuracy of the ceramic member 20. The one main surface 32 of the metal member 30 is the bonding surface with the ceramic member 20. The metal member 30 having a large thickness means that the maximum thickness in a direction perpendicular to the one main surface 32 of the metal member 30 is 1 mm or more. If the maximum thickness of the metal member 30 is less than 1 mm, the effect of improving dimensional accuracy will not be fully achieved, and therefore it is preferable that the maximum thickness be 1 mm or more.

[0034] The maximum thickness of the metal member 30 in the direction perpendicular to one main surface 32 is preferably set to a thickness according to the intended use. Considering that there has not been a joined body of metal members 30 with a large thickness like that of the present invention, depending on the intended use, the thickness is preferably 2 mm or more, more preferably 3 mm or more, and even more preferably 4 mm or more.

[0035] The ceramic member 20 preferably includes a second phase made of a metal oxide. The ceramic member 20 includes a second phase made of a metal oxide, which bonds the ceramic member 20 and the metal member 30 together. This strengthens the bond between the ceramic member 20 and the metal member 30, thereby improving the reliability of the bonded body 10. The metal constituting the metal oxide of the second phase is preferably one or more selected from Y and Ca, and more preferably Y. The metal oxide constituting the second phase may be a sintering aid for the ceramic member 20, which is mainly composed of AlN. In this case, the metal oxide constituting the second phase may be added in a required amount as a sintering aid for the ceramic member 20. For example, when Y is added as a sintering aid, it may be added in an amount of 0.1 wt% to 5 wt% in terms of Y2O3.

[0036] At the bonding interface between the ceramic member 20 and the metal member 30, the concentration of the metal constituting the second phase of the ceramic member 20 and the concentration of oxygen are preferably higher than the concentration of the metal and the concentration of oxygen inside the ceramic member 20. In this way, the concentration of the metal and the concentration of oxygen constituting the second phase at the bonding interface between the ceramic member 20 mainly composed of AlN and the metal member 30 made of a high-melting-point metal are higher than the concentration of the metal and the concentration of oxygen inside the ceramic member 20, respectively, so that the ceramic member 20 and the metal member 30 are bonded together via these, and a bonded body in which erosion and contamination of the bonding surface are suppressed can be obtained.

[0037] The bonding interface between the ceramic member 20 and the metal member 30 refers to the interface where the concentration of the metal element that mainly constitutes the metal member 30 drops sharply in cross-sectional elemental mapping by EDX or EPMA. The interior of the ceramic member 20 refers to a region at least 1 mm away from the bonding interface. In addition, when the ceramic member 20 contains a second phase made of a metal oxide, the interior refers to a region where the concentration of the metal that constitutes the second phase of the ceramic member 20 is uniform.

[0038] The change in the concentration of metal present in the ceramic member 20, the metal member 30, or their bonded interface can be determined by comparing the intensity (count number) of characteristic X-rays in the relevant region using an EPMA. This allows the relative evaluation of the difference in metal and oxygen concentration near and inside the interface.

[0039] It is preferable that the ceramic member 20 further contains a Group 4 metal, and that the Group 4 metal is diffused in the metal member 30. In this way, when the ceramic member 20 contains a Group 4 metal and the Group 4 metal is diffused in the metal member 30, the bonding strength between the ceramic member 20 and the metal member 30 is increased, and the reliability of the bonded body 10 is improved. The Group 4 metal is preferably one or more selected from Ti and Hf, and more preferably Ti.

[0040] The relative density of the metal member 30 is preferably 95% or more and 99.9% or less. When the relative density of the metal member 30 is 95% or more and 99.9% or less, the internal residual stress is alleviated, and the dimensional accuracy and processing accuracy can be improved.

[0041] FIG. 2 is a schematic cross-sectional view illustrating a modified example of a bonded body according to an embodiment of the present invention. As shown in FIG. 2, the bonded body 10 preferably further includes a ceramic member 20 primarily composed of AlN bonded to the other main surface 34 of the metal member 30, opposite the one main surface 32. Bonding the ceramic members 20 to both main surfaces 32, 34 of the metal member 30 in this manner further expands the range of uses of the bonded body 10. Furthermore, sandwiching a plate-shaped high-melting-point metal (metal member 30) between the ceramic members 20 can suppress warping of the bonded body 10, thereby enabling the fabrication of a bonded body 10 with high dimensional accuracy. The combination of the one main surface 32 and the other main surface 34 is referred to as both main surfaces 32, 34, or the main surfaces 32, 34. The bonded body 10 may also have a ceramic member 20 bonded to a surface other than the main surfaces 32, 34.

[0042] [Configuration of electrode embedding material] Next, an electrode-embedded member according to an embodiment of the present invention will be described. Fig. 3 is a schematic cross-sectional view showing an example of an electrode-embedded member according to an embodiment of the present invention. An electrode-embedded member 50 according to an embodiment of the present invention includes a bonded body 10 and an electrode 40 embedded in a ceramic member 20 of the bonded body 10.

[0043] The joined body 10 is the joined body 10 described above. The electrode 40 is embedded in the ceramic member 20 of the joined body 10. The electrode 40 may have various shapes, such as a mesh shape or a foil shape. The electrode 40 may be made of various materials, such as molybdenum or tungsten. A heater electrode may be used as the electrode 40.

[0044] The electrode-embedding member 50 may be provided with terminal holes and terminals (not shown).

[0045] The bonded body and electrode-embedded member of the present invention are members that suppress erosion and contamination of the bonding surface between a ceramic member mainly composed of AlN and a metal member made of a high-melting-point metal. Furthermore, since the bonded body and electrode-embedded member of the present invention have a thick metal member, they can be used in a variety of applications, such as using the metal member as a heat sink or heat spreader, or improving the strength and dimensional accuracy of the ceramic member.

[0046] [Method of manufacturing the bonded body] Next, a method for manufacturing the bonded body 10 configured as described above will be described. Figures 4(a) to 4(e) are cross-sectional views each schematically showing one stage of a manufacturing process of a manufacturing method according to an embodiment of the present invention. The manufacturing method according to an embodiment of the present invention includes a method using a porous body made of a high-melting-point metal (high-melting-point metal porous body) as the metal member, and a method using a dense body made of a high-melting-point metal. In this specification, a porous body made of a high-melting-point metal refers to a member made of a high-melting-point metal with a relative density of 40% or more and 90% or less. A dense body made of a high-melting-point metal refers to a member made of a high-melting-point metal with a relative density of 95% or more.

[0047] First, AlN raw material powder is granulated to produce granulated powder 22. The AlN raw material powder preferably has a high purity, preferably 96% or higher, and more preferably 98% or higher. The average particle size of the AlN raw material powder is preferably 0.1 μm or higher and 1.0 μm or lower, and more preferably 0.3 μm or higher and 0.8 μm or lower. A binder such as a PVA-based binder, a dispersant, and a solvent are added to the AlN raw material powder to prepare a slurry, which is then granulated into granulated powder 22 using a spray dryer or the like.

[0048] When the ceramic member is to have a configuration including a second phase made of a metal oxide, a powder obtained by adding a metal oxide raw powder to an AlN raw powder is granulated. When, for example, Y2O3 is used as the metal oxide raw powder, 0.1 wt% to 5 wt% of Y2O3 is added to the AlN raw powder and granulated.

[0049] Next, when manufacturing using a porous body made of a high-melting point metal, a plate-shaped high-melting point metal porous body 36 is prepared, which has a relative density of 40% to 90% and a thickness of 1 mm or more in the pressure direction after uniaxial pressure sintering in a direction perpendicular to the main surface. A porous body with a relative density of less than 40% may be difficult to manufacture. A porous body with a relative density of more than 90% may have a reduced anchoring effect. Note that the thickness of the plate-shaped high-melting point metal porous body 36 is preferably adjusted so that the relative density after uniaxial pressure sintering is 95% to 99.9%. Figures 4(a) to 4(e) show a manufacturing method using a plate-shaped high-melting point metal porous body 36.

[0050] On the other hand, when manufacturing using a dense body made of a refractory metal, a plate-shaped dense body of refractory metal with a thickness of 1 mm or more is prepared, and the main surface to be joined of the refractory metal is roughened. The main surface of the refractory metal is preferably roughened so that the surface roughness Ra is 1.0 μm or more and 20 μm or less. For simplicity, only a method using a plate-shaped porous refractory metal 36 will be described below, but the plate-shaped porous refractory metal 36 can be replaced with a roughened plate-shaped refractory metal.

[0051] Next, the granulated powder 22 or a molded body formed from the granulated powder and the plate-shaped high-melting point metal porous body 36 are stacked in a bottomed carbon mold 60 (molding mold) so that one main surface of the plate-shaped high-melting point metal porous body 36 is perpendicular to the stacking direction.

[0052] As another example of laminating compacts, one or more compacts are produced using the obtained granulated powder 22. As a method for forming the compacts, known methods such as uniaxial pressing or cold isostatic pressing (CIP) may be used. Note that the method for forming the compacts is not limited to pressure forming, and for example, green sheet lamination or slip casting may also be applied.

[0053] When producing electrode-embedded member 50, when stacking granulated powder 22, granulated powder 22 is pre-pressed, electrode 40 is arranged, and granulated powder 22 is further added and pre-pressed, or compacts are stacked, electrode 40 is arranged, and further compacts are stacked, whereby electrode 40 is embedded in the portion that will become ceramic member 20 after firing.

[0054] Next, a carbon punch 70 is inserted into the carbon mold 60 to form the laminate 12. The laminate 12 may be a two-layer structure consisting of a layer of granulated powder 22 or a compact that will become the ceramic member 20 after firing and a plate-shaped refractory porous metal 36 that will become the metal member 30 after firing, or a three-layer structure in which the plate-shaped refractory porous metal 36 is sandwiched between layers of granulated powder 22 or a compact. The side surfaces in the stacking direction may have portions where the plate-shaped refractory porous metal 36 is exposed, or the plate-shaped refractory porous metal 36 may be covered with the granulated powder 22 or a compact. FIG. 4 shows a three-layer structure in which the plate-shaped refractory porous metal 36 is covered with the granulated powder 22.

[0055] Next, the laminate 12 is uniaxially pressurized and fired to produce the bonded body 10. The firing conditions are, for example, a temperature of 1700°C to 2000°C, a pressure of 1 MPa or more, and a holding time of 0.1 to 10 hours. When using a plate-shaped high-melting-point porous metal 36 for production, the pressure during firing is preferably adjusted so that the relative density of the plate-shaped high-melting-point porous metal 36 after firing is 95% to 99.9%.

[0056] After firing, a process for processing the plate-shaped porous refractory metal 36 into a predetermined shape may be performed. At this time, if the side surfaces of the plate-shaped porous refractory metal 36 in the stacking direction are covered with the ceramic members 20, processing may be performed to expose the plate-shaped porous refractory metal 36. Also, if the plate-shaped porous refractory metal 36 is a three-layer structure sandwiched between layers of ceramic members 20, processing may be performed to remove some of the ceramic members 20 or all of one of the ceramic members 20. Also, a process for processing the shape of the plate-shaped porous refractory metal 36 may be performed. At this time, processing is performed so that the maximum thickness of the plate-shaped porous refractory metal 36 in the direction perpendicular to one main surface is not less than 1 mm.

[0057] In addition, in the case of using the electrode-embedding member 50, a step of exposing a part of the electrode 40 and a step of connecting a terminal to the electrode 40 may be provided.

[0058] The method for producing and laminating a compact may include a step of degreasing the compact to produce a degreased body and a step of calcining the degreased body to produce a calcined body. In this case, for example, the degreasing temperature is preferably 400°C or higher and 800°C or lower, and the degreasing time is preferably 1 hour or higher and 120 hours or lower. The degreasing atmosphere is preferably an air atmosphere or a nitrogen atmosphere, and more preferably an air atmosphere. Furthermore, for example, the calcination temperature is preferably 1200°C or higher and 1700°C or lower, and the calcination time is preferably 0.5 hours or higher and 12 hours or lower. The calcination atmosphere is preferably a nitrogen or inert gas atmosphere, but may also be a vacuum atmosphere.

[0059] By using this method, it is possible to manufacture a bonded body or an electrode-embedded member in which corrosion and contamination of the bonding surfaces of a ceramic member mainly composed of AlN and a metal member made of a high-melting-point metal are suppressed.

[0060] [Example] (Preparation of junction) Example 1 5 wt% of Y2O3 was added to the AlN raw powder, and a binder (PVA), dispersant, and solvent were added to prepare a slurry, which was then granulated using a spray dryer. In addition, a plate-shaped Mo porous body with a diameter of 50 mm, a thickness of 6.7 mm, and a relative density of 75% was prepared as a high-melting-point porous metal body to be used as the metal component.

[0061] Next, the granulated powder was filled into a bottomed carbon mold and press-molded with a carbon punch to produce a compact with a diameter of 80 mm and a thickness of 10 mm. Next, a Mo porous body was placed on the compact. Next, the carbon mold was further filled with the granulated powder to embed the Mo porous body. At this time, the granulated powder was filled and molded with the carbon punch so that the thickness from the top surface of the Mo porous body was 10 mm.

[0062] Then, with the carbon punch inserted into the carbon mold, uniaxial hot press sintering was performed for 2 hours at a temperature of 1800°C, a pressure of 4 MPa, and a N2 atmosphere. This resulted in a 50 mm diameter metal member made of Mo being embedded inside an 80 mm diameter AlN sintered body. In this way, the bonded body of Example 1 was produced. After that, multiple test pieces of Example 1 measuring 3 mm x 4 mm x 19 mm were cut out so that the long sides were aligned in the stacking direction. The relative density of the metal member after sintering was 96%.

[0063] Example 2 A joined body of Example 2 was produced using the same process and conditions as in Example 1, except that the high-melting-point porous metal body was replaced with a plate-shaped porous W body having a diameter of 50 mm, a thickness of 5 mm, and a relative density of 60%. The relative density of the metal member after firing was 96%.

[0064] Example 3 A joined body of Example 3 was produced using the same process and conditions as in Example 1, except that the high-melting-point porous metal body was replaced with a plate-shaped dense Mo body having a diameter of 50 mm, a thickness of 5 mm, and a relative density of 98%, and both the upper and lower principal surfaces were sandblasted to roughen them to Ra 12 μm. The relative density of the metal member after firing was 99%.

[0065] Example 4 A joined body of Example 4 was produced using the same process and conditions as in Example 3, except that the Mo dense body was roughened to Ra 20 μm by iris knurling. The relative density of the metal member after firing was 99%.

[0066] Example 5 A joined body of Example 5 was produced using the same process and conditions as in Example 1, except that the granulated powder was changed to one without added Y2O3. The relative density of the metal members after firing was 96%.

[0067] Example 6 A joined body of Example 6 was produced using the same process and conditions as in Example 1, except that the granulated powder was changed to AlN raw material powder to which 5 wt% Y2O3 and 0.9 wt% TiN were added. The relative density of the metal members after firing was 96%.

[0068] (Comparative Example 1) An AlN sintered body (ceramic member) was produced by changing the granulated powder of Example 1 to one without adding YO. A plate-shaped Mo dense body with a diameter of 50 mm, a thickness of 5 mm, and a relative density of 98% was prepared as the metal member. The ceramic member and the metal member were then joined using a brazing material (activated gold brazing material made of BAu-4 with added Ti) to produce a joined body of Comparative Example 1.

[0069] (Comparative Example 2) A bonded body of Comparative Example 2 was produced using the same process and conditions as Comparative Example 1, except that the brazing material was changed to a silicone adhesive.

[0070] (Bonding strength measurement) The bond strength of the bonded bodies was measured using a three-point bending strength test in accordance with JIS R1601 2008 (room temperature bending strength test method for fine ceramics). The span was 10 mm, and the bond surface was placed at the center in the longitudinal direction, with the knife edge aligned with the bond surface. Five test pieces were prepared for each sample, and the average of the five measurements was used as the bond strength value for each sample.

[0071] (Measurement results) In Comparative Example 1, the bonding strength was 65 MPa, and sufficient bonding strength was not obtained. In Comparative Example 2, the bonding strength was 10 MPa, and sufficient bonding strength was not obtained. In contrast, Examples 1 and 2 had bonding strengths of 140 MPa and 110 MPa, respectively, and it was found that high bonding strength was obtained. In Examples 3 and 4, the bonding strengths were 90 MPa and 87 MPa, respectively, and sufficient bonding strength was obtained, which was higher than that of the samples of Comparative Examples 1 and 2. In Examples 5 and 6, the bonding strengths were 160 MPa and 150 MPa, respectively, and were higher than that of the samples of Comparative Examples 1 and 2, and further higher than that of Examples 1 to 4.

[0072] Next, a cut surface perpendicular to the lamination direction of the sample of Example 1 was observed under a microscope at 1000x magnification. Figure 5 is a micrograph of a cross section of the bonded interface of the bonded body of Example 1. As shown in Figure 5, at the bonded interface of Example 1, Mo had penetrated into the irregularities of the AlN ceramic. As a result, no gaps were observed at the bonded interface.

[0073] Next, elemental analysis was performed using an EPMA on a cut surface perpendicular to the lamination direction of the sample of Example 1. The results of the elemental analysis revealed that Y and O were present in the ceramic member (AlN), but were present in greater amounts at the bonding interface between the ceramic member and the metal member (Mo), which is made of a high-melting-point metal. In other words, it was confirmed that the metal concentration and oxygen concentration constituting the second phase of the ceramic member at the bonding interface between the ceramic member and the metal member were greater than the metal concentration and oxygen concentration, respectively, within the ceramic member.

[0074] The manufacturing method of the present invention involves uniaxial pressure sintering of a porous refractory metal or a refractory metal with a roughened surface with an unsintered ceramic raw material, which is believed to result in a significant anchoring effect, as the refractory metal penetrates into the irregularities of the AlN ceramic at the bonding interface, or vice versa. Furthermore, because the sintering temperature exceeds the recrystallization temperature of the refractory metal, plastic deformation of the refractory metal at the bonding interface is believed to result in even greater bonding strength.

[0075] Furthermore, when the ceramic member contains a second phase consisting of a metal oxide, the bonded body of the present invention may have high bonding strength due to the presence of high concentrations of metal and oxygen that constitute the second phase of the ceramic member at the bonding interface between the ceramic member and the metal member, and chemical bonding between the high-melting point metal and AlN through these.

[0076] Example 7 (Production of electrode-embedded member) In Example 7, a heater electrode was embedded in an AlN sintered body (ceramic member) located on Mo in the manufacturing method of Example 1, and a heater module that can be used in high-temperature processes was produced.

[0077] The granulated powder prepared was the same as that prepared in Example 1. Furthermore, a plate-shaped Mo porous body having a diameter of Φ300 mm, a thickness of 10.7 mm, and a relative density of 75% was prepared as a high-melting-point porous metal body to be used as the metal member.

[0078] First, a heater laminate was produced. The granulated powder was filled into a bottomed carbon mold and press-molded with a carbon punch to produce a compact with a diameter of 320 mm and a thickness of 8 mm. Next, a heater electrode was placed on the mold. The heater electrode was a Mo mesh (wire diameter 0.1 mm, mesh size #50, plain weave) cut into a predetermined pattern to match the resistance value of the heater electrode. Next, the granulated powder was further filled into the carbon mold to embed the heater electrode, producing a heater laminate. At this time, the granulated powder was filled and molded with a carbon punch so that the thickness from the top surface of the heater electrode was 8 mm.

[0079] Next, a plate-shaped Mo porous body was placed on the heater laminate. The carbon mold on which the Mo porous body was placed was further filled with granulated powder to embed the Mo porous body. At this time, the plate-shaped Mo porous body was formed with a carbon punch so that the thickness from the top surface was 8 mm, and a laminate was produced. In this way, a laminate in which the heater laminate and the plate-shaped Mo porous body were stacked was produced.

[0080] Then, with the carbon punch inserted into the carbon mold, uniaxial hot press firing was performed at a temperature of 1800°C, a pressure of 4 MPa, and a N2 atmosphere for 4 hours. After firing, the outer shape (Φ300 mm x 18 mm) was processed. Drilling terminal holes for connecting each electrode to an external power source, connecting the terminals, and fabricating the necessary insulating structure were all performed simultaneously during processing after firing. In this way, the electrode-embedded member of Example 4 was produced.

[0081] (evaluation) The fabricated heater module could be heated to 400°C by applying electricity to the heater electrodes from an external power source.

[0082] From the above, it was confirmed that the bonded body and electrode-embedded member of the present invention can suppress erosion and contamination of the bonding surface, have high bonding strength, and have thick metal members. It was also confirmed that the manufacturing method of the present invention can manufacture such a bonded body or electrode-embedded member.

[0083] The present invention is not limited to the above-described embodiments, and various modifications and equivalents are included within the spirit and scope of the present invention. Furthermore, the structure, shape, number, position, size, etc. of the components shown in each drawing are for the convenience of explanation and may be changed as appropriate. [Explanation of symbols]

[0084] 10 zygote 12 Laminate 20 Ceramic materials 22 Granulated powder 30 Metallic parts 32 One main surface 34 Other main surface 36 Plate-shaped high-melting-point porous metal 40 electrodes 50 Electrode embedding member 60 Carbon type 70 Carbon Punch

Claims

1. A joined body of a ceramic member mainly composed of AlN and a metal member made of a high-melting point metal having a melting point of 2000°C or more, the ceramic member is joined to at least one main surface of the metal member such that one main surface of the ceramic member and one main surface of the metal member are in direct contact with each other; The metal member has a maximum thickness of 1 mm or more in a direction perpendicular to one main surface of the metal member, A bonded body characterized in that the bonded interface of the ceramic member and the metal member has a three-point bending strength of 70 MPa or more.

2. 2. The joined body according to claim 1, wherein the ceramic member includes a second phase made of a metal oxide.

3. the ceramic member contains a Group 4 metal; 3. The joined body according to claim 1, wherein the metal member has the Group 4 metal diffused therein.

4. 4. The joined body according to claim 1, wherein the relative density of the metal members is 95% or more and 99.9% or less.

5. 5. The joined body according to claim 1, wherein a ceramic member mainly composed of AlN is further joined to the other main surface of the metal member opposite to the one main surface.

6. The bonded body according to any one of claims 1 to 4, an electrode embedded in the ceramic member of the joined body;

7. A method for manufacturing a joined body of ceramic members mainly composed of AlN and metal members made of Mo, a high-melting point metal having a melting point of 2000°C or higher, comprising: granulating the AlN raw material powder to produce granulated powder; preparing a plate-shaped refractory metal porous body made of the refractory metal, which has a relative density of 40% to 90% and a thickness of 1 mm or more in the pressing direction after uniaxial pressure sintering in a direction perpendicular to a main surface; a step of stacking the granulated powder or the compact formed from the granulated powder and the plate-shaped refractory metal porous body on a carbon mold so that the granulated powder or the compact formed from the granulated powder and the main surface of the plate-shaped refractory metal porous body are in direct contact with each other and so that the main surface of the plate-shaped refractory metal porous body is perpendicular to the stacking direction; inserting a carbon punch into the carbon mold to form a laminate; and uniaxially pressing and firing the laminate at a temperature of 1800°C or higher.

8. A method for manufacturing a joined body of ceramic members mainly composed of AlN and metal members made of Mo, a high-melting point metal having a melting point of 2000°C or higher, comprising: granulating the AlN raw material powder to produce granulated powder; A step of roughening a main surface to be joined of the plate-shaped high melting point metal having a thickness of 1 mm or more; stacking the granulated powder or the compact formed from the granulated powder, and the plate-shaped high-melting point metal on a carbon mold so that the main surface of the plate-shaped high-melting point metal contacts the granulated powder or the compact formed from the granulated powder perpendicular to a stacking direction; inserting a carbon punch into the carbon mold to form a laminate; and uniaxially pressing and firing the laminate at a temperature of 1800°C or higher.

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