Electrode-embedding member and manufacturing method thereof

Abstract

To provide an electrode-embedding member and a manufacturing method thereof, which can suppress the intrusion of oxygen between a connecting member and a ceramic sintered body, suppress deterioration of the connecting member, and extend the product life compared to conventional products.SOLUTION: An electrode-embedded member 100 includes a base 110 formed in a flat plate shape from a ceramic sintered body whose main component is AlN, an electrode 120 embedded in the base 110, and a connection member 130 made of W or Mo and electrically connected to the electrode 120 and embedded in the base 110, and a porous layer 132 made of W or Mo is formed at the interface between the connection member 130 and the ceramic sintered body.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

[0002] 2. Description of the Related Art Conventionally, there have been proposed, as members for semiconductor manufacturing equipment, members with embedded electrodes, such as susceptors having electrodes embedded in a ceramic sintered body, electrostatic chucks, or ceramic heaters.

[0003] Patent Document 1 discloses a holding device technology for holding an object on the surface of a ceramic member, the holding device comprising: a ceramic member formed of a ceramic sintered body whose main component is aluminum nitride; a metallic heating resistor disposed inside the ceramic member; a conductive power supply connection member in contact with the heating resistor; and a conductive power supply terminal electrically connected to the power supply connection member, the holding device having the objective of suppressing variations in the amount of heat generated by a heating resistor resulting from variations in the resistance value of a power supply connection member, wherein at least a portion of the surface of the power supply connection member, excluding the contact surface with the heating resistor and the connection surface with the power supply terminal, is covered with a coating layer formed of a nitride containing at least one of Al, Ti, Zr, V, Ta, and Nb. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6867550 Summary of the Invention [Problem to be solved by the invention]

[0005] In conventional electrode embedding members, oxygen may penetrate through the terminal holes into the interface between the embedded connection member and the ceramic sintered body, causing the connection member to deteriorate. If the electrode embedding member is used in this state, the difference in physical properties between the connection member and the ceramic sintered body increases, and the electrode embedding member is no longer able to function properly, reaching the end of its product life. Therefore, there has been a demand for an electrode embedding member that suppresses such deterioration of the connection member and has a longer product life than conventional products, and a method for manufacturing the same.

[0006] In the technology described in Patent Document 1, the surface of the power supply connecting member is covered with a coating layer, which can prevent the power supply connecting member from reacting with impurities during firing to form an altered layer on the surface of the power supply connecting member. However, Patent Document 1 does not take into consideration the prevention of oxidation of the connecting member when the electrode embedding member is used, and it is unclear whether oxidation of the connecting member can be prevented when the electrode embedding member is used.

[0007] The inventors discovered that by forming a porous layer at the interface between the connecting member and the ceramic sintered body, it is possible to prevent oxygen from entering between the connecting member and the ceramic sintered body, and thereby to prevent deterioration of the connecting member, and thus completed the present invention.

[0008] In other words, the present invention has been made in consideration of the above-mentioned circumstances, and aims to provide an electrode-embedded member and a manufacturing method thereof that can suppress the intrusion of oxygen between the connecting member and the ceramic sintered body, suppress deterioration of the connecting member, and extend the product life compared to conventional products. [Means for solving the problem]

[0009] (1) In order to achieve the above object, the electrode-embedding member of the present invention has the following features: That is, the electrode-embedded member of the application example of the present invention is an electrode-embedded member comprising a base formed in a flat plate shape from a ceramic sintered body mainly composed of AlN, an electrode embedded in the base, and a connection member made of W or Mo, electrically connected to the electrode and embedded in the base, characterized in that a porous layer made of W or Mo is formed at the interface between the lower surface of the connection member and the ceramic sintered body.

[0010] As a result, the porous layer on the underside of the connection member creates an anchor effect between the connection member and the ceramic sintered body, improving adhesion, preventing oxygen from entering between the connection member and the ceramic sintered body, and preventing deterioration of the connection member, which makes it possible to extend the product life of the electrode-embedded member compared to conventional products.

[0011] (2) In the electrode-embedding member according to the application example of (1) above, the porous layer is formed on the upper surface and the side surface of the connection member.

[0012] This increases the anchor effect between the connection member and the ceramic sintered body, and further suppresses the intrusion of oxygen through the terminal holes, thereby further suppressing deterioration of the connection member, thereby making it possible to extend the product life of the electrode-embedding member compared to conventional products.

[0013] (3) In the electrode-embedding member according to the application example of (1) above, the porous layer is formed on an upper surface of the connection member.

[0014] This increases the anchor effect between the connection member and the ceramic sintered body, and further suppresses the intrusion of oxygen through the terminal hole, thereby further suppressing deterioration of the connection member. As a result, deterioration can be suppressed, and the product life of the electrode-embedded member can be made longer than that of conventional products.

[0015] (4) Furthermore, a manufacturing method of an electrode-embedded member according to an application example of the present invention includes a molded body preparation step of preparing a plurality of molded bodies formed of a ceramic containing AlN as a main component; an electrode, etc. preparation step of preparing an electrode, a connecting member made of W or Mo, and a paste containing W or Mo; a paste application step of applying the paste to a predetermined surface of at least the lower surface of the connecting member; a precursor formation step of combining the electrode, the connecting member with the paste applied, and the plurality of molded bodies to form an electrode-embedded member precursor formed in a flat plate shape and having the electrode and the connecting member embedded therein; and a firing step of uniaxially pressurizing and firing the electrode-embedded member precursor in a direction perpendicular to one main surface of the electrode-embedded member precursor to fire the electrode-embedded member.

[0016] This allows the paste containing W or Mo to become a porous layer made of W or Mo during the firing process, improving the adhesion between the connection member and the ceramic sintered body, suppressing the intrusion of oxygen between the connection member and the ceramic sintered body, and enabling the manufacture of an electrode-embedded member that can suppress deterioration of the connection member.As a result, the product life of the electrode-embedded member can be made longer than conventional products. Effect of the Invention

[0017] According to the present invention, the intrusion of oxygen between the connection member and the ceramic sintered body can be suppressed, and deterioration of the connection member can be suppressed, resulting in a longer product life of the electrode-embedded member than that of conventional products. [Brief description of the drawings]

[0018] [Figure 1] 1 is a cross-sectional view showing an example of an electrode-embedded member according to an embodiment of the present invention. [Diagram 2] 2 is a partially enlarged view of the electrode-embedded member of FIG. 1. [Diagram 3] 4 is a flowchart showing an example of a method for manufacturing an electrode-embedded member according to an embodiment of the present invention. [Figure 4]1(a) to 1(c) are cross-sectional views each showing a schematic diagram of one stage in a manufacturing process for an electrode-embedded member according to an embodiment of the present invention. [Diagram 5] 1(a) to 1(c) are cross-sectional views each showing a schematic diagram of one stage in a manufacturing process for an electrode-embedded member according to an embodiment of the present invention. [Figure 6] 3A to 3C are cross-sectional views each showing a schematic diagram of a step in a manufacturing process of an electrode-embedded member according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Next, an embodiment of the present invention will be described with reference to the drawings. In order to facilitate understanding of the description, the same reference numerals are used for the same components in each drawing, and duplicated descriptions will be omitted. In the configuration diagrams, the size of each component is conceptually shown, and does not necessarily represent the actual dimensional ratio.

[0020] [Embodiment] [Configuration of electrode embedding material] An electrode-embedded member according to an embodiment of the present invention will be described with reference to Fig. 1 and Fig. 2. Fig. 1 is a cross-sectional view showing an example of an electrode-embedded member according to an embodiment of the present invention. Fig. 2 is a partially enlarged view of the electrode-embedded member of Fig. 1. An electrode-embedded member 100 according to an embodiment of the present invention includes a base 110, an electrode 120, and a connection member 130. The electrode-embedded member 100 is applied to an RF base, a ceramic heater, an electrostatic chuck, and the like.

[0021] The base 110 is formed into a flat plate shape from a ceramic sintered body mainly composed of AlN. One of the main surfaces of the base 110 has a mounting surface 112 on which a substrate is mounted. The shape of the base 110 may be various shapes such as a substantially circular plate, a polygonal plate, or an elliptical plate.

[0022] A ceramic sintered body mainly composed of AlN means that the ceramic sintered body contains 90wt% or more of AlN. In order to adjust the physical properties of AlN ceramics, such as increasing the thermal conductivity, sintering aids made of oxides of 2a group elements or 3a group elements are often added. In general, it is known that the thermal conductivity increases when the amount of sintering aid added is increased, but adding more than a certain amount causes a decrease in thermal conductivity. Therefore, it is desirable to keep the content of sintering aids made of oxides of 2a group elements or 3a group elements to 10wt% or less. Examples of additives of 2a group elements include Mg, Ca, Sr, Ba, etc., and examples of additives of 3a group elements include Y, La, Sm, Ce, etc.

[0023] A ceramic sintered body mainly composed of AlN has high thermal conductivity and excellent heat resistance and plasma resistance, and physical properties such as thermal conductivity can be easily adjusted by adjusting the type and amount of sintering aid added. Therefore, by forming the base 110 from a ceramic sintered body mainly composed of AlN, it is possible to configure a base 110 with adjusted thermal conductivity, excellent heat resistance and plasma resistance.

[0024] The electrode 120 is embedded in the base 110. The electrode 120 is used, for example, as a high-frequency electrode. An electrode used for other purposes, for example, a heater electrode or an electrostatic attraction electrode, may be embedded. The electrode 120 may have various shapes, such as a mesh shape or a foil shape, depending on the design of the electrode-embedded member 100. The electrode 120 is preferably made of Mo, W, or an alloy containing these.

[0025] The base 110 may have a plurality of electrodes. In this case, the connection member electrically connected to at least one of the electrodes may be the connection member 130 of the present invention described below. A plurality of connection members may be the connection member 130 of the present invention.

[0026] The connection member 130 is embedded in the base 110 and electrically connected to the electrode 120. This allows electricity to be supplied to the electrode 120 via the connection member 130. The connection member 130 is made of W or Mo. The connection member 130 being made of W or Mo means that the purity of W or Mo is 50 wt % or more.

[0027] The shape of the connection member 130 may be various shapes such as a flat, approximately circular plate, a polygonal plate, or an elliptical plate, or may be a truncated cone whose radial dimension changes in the thickness direction. Among these, the shape of the connection member 130 is preferably approximately circular plate. When the connection member 130 is formed in an approximately circular plate shape, its diameter φ is preferably 5 mm or more and 10 mm or less. The thickness of the connection member 130 is preferably 0.1 mm or more and 0.5 mm or less. If the thickness of the connection member 130 is smaller than 0.1 mm, there is a possibility that the connection member 130 may be damaged when the terminal hole 142 is provided to connect the terminal 140. If the thickness of the connection member 130 is larger than 0.5 mm, there is a possibility that the base 110 may crack due to the difference in the contraction rate during firing and the difference in the thermal expansion rate during use between the connection member 130 and the ceramic of the base 110.

[0028] A porous layer 132 made of W or Mo is formed at the interface between the lower surface of the connection member 130 and the ceramic sintered body. This makes it possible to prevent oxygen that has entered the terminal hole 142 from entering between the lower surface of the connection member 130 and the ceramic sintered body, thereby making it possible to prevent deterioration of the connection member 130. As a result, the product life of the electrode-embedded member 100 can be made longer than that of conventional products. In addition, the reliability of the electrical connection via the connection member 130 can be further improved.

[0029] The interface between the lower surface of the connecting member 130 and the ceramic sintered body is the portion where the lower surface of the connecting member 130 and the ceramic sintered body come into contact. It is presumed that the reason why the intrusion of oxygen from between the lower surface of the connecting member 130 and the ceramic sintered body can be suppressed is that the porous layer 132 made of W or Mo is formed at the interface between the lower surface of the connecting member 130 and the ceramic sintered body, thereby improving the adhesion between the connecting member 130 and the ceramic sintered body. The thickness of the porous layer 132 is preferably 5 μm to 500 μm. The porous layer 132 is a layer having 4 pores with a maximum diameter of 1 μm or more per 10 μm in a field of view at a magnification of 500 times. 2 The term "layer" refers to a region in which the above-mentioned regions exist.

[0030] In addition, the porous layer 132 may be formed on the surface of the connection member 130 other than the interface with the ceramic sintered body on the lower surface of the connection member 130. For example, the porous layer 132 made of W or Mo may be formed on the upper surface and side surface of the connection member 130. Also, the porous layer 132 made of W or Mo may be formed on the upper surface of the connection member 130. This increases the anchor effect between the connection member 130 and the ceramic sintered body, further suppresses the intrusion of oxygen from the terminal hole 142, and further suppresses the deterioration of the connection member 130. As a result, the product life of the electrode-embedded member 100 can be further extended compared to conventional products. In addition, by manufacturing the connection member 130 so that the porous layer 132 made of W or Mo is formed on the lower surface and upper surface, the electrode preparation process described later is facilitated, and a member with a long life function can be easily manufactured.

[0031] The present invention only requires that the intrusion of oxygen from between the connecting member 130 and the ceramic sintered body is suppressed. Therefore, the porous layer 132 made of W or Mo formed at the interface between the lower surface of the connecting member 130 made of W or Mo and the ceramic sintered body includes all combinations of the connecting member 130 made of W and the porous layer 132 made of W, the connecting member 130 made of W and the porous layer 132 made of Mo, the connecting member 130 made of Mo and the porous layer 132 made of Mo, and the connecting member 130 made of Mo and the porous layer 132 made of W. However, it is preferable that the main components of the materials of the connecting member 130 and the porous layer 132 are the same. When the main components are the same, the adhesion between the connecting member 130 and the porous layer 132 is further improved.

[0032] The terminal 140 is inserted into the terminal hole 142 and electrically connected to the connection member 130. This makes it possible to supply power to the electrode 120. The terminal 140 can be made of Ni or the like. The terminal 140 is brazed to the connection member 130 with Au solder or the like. A buffer member 144 made of W, Mo, Kovar or the like may be provided between the connection member 130 and the terminal 140. A plurality of buffer members 144 may be provided.

[0033] The terminal holes 142 are drilled from the lower surface of the base 110. The terminal holes 142 are drilled to a depth that allows the connection members 130 to be exposed.

[0034] The electrode-embedding member 100 of the present invention can suppress the intrusion of oxygen from between the connection member 130 and the ceramic sintered body, and can suppress the deterioration of the connection member 130. As a result, the product life of the electrode-embedding member can be made longer than that of conventional products. In particular, the influence on the insulating layer 114 of the base 110 on the upper surface of the electrode 120 can be suppressed, and therefore the reliability of the electrode-embedding member 100 can be increased.

[0035] [Method of manufacturing electrode-embedded members] Next, a method for manufacturing the electrode-embedded member according to the present embodiment will be described. The electrode-embedded member according to the present embodiment is manufactured, for example, by a molded body hot pressing method described below. The manufacturing method is not limited to this method, and may be, for example, a powder hot pressing method or a conventional green sheet lamination method. The powder hot pressing method is a method in which ceramic raw material powder and a predetermined heating resistor and electrodes are alternately stacked to embed the heating resistor and electrodes inside the ceramic, and then the resulting product is uniaxial hot press sintered.

[0036] 3 is a flow chart showing a method for producing an electrode-embedded member according to an embodiment of the present invention. As shown in FIG. 3, the method for producing an electrode-embedded member according to a first embodiment of the present invention includes a green body preparation step (STEP 1), an electrode preparation step (STEP 2), a paste application step (STEP 3), a precursor formation step (STEP 4), and a firing step (STEP 5).

[0037] Figures 4(a) to (c), 5(a) to (c), and 6 are cross-sectional views each showing a schematic diagram of a manufacturing process for the electrode-embedded member according to the present embodiment. Figures 4 to 6 show a manufacturing process using a molded body hot pressing method. Figures 4 to 6 show the manufacturing process for the electrode-embedded member of Figure 1.

[0038] In the compact preparation step STEP 1, multiple compacts are prepared from ceramics mainly composed of AlN. The compacts in the compact preparation step STEP 1 include ceramic compacts in the compact hot pressing method, ceramic degreased bodies, ceramic calcined bodies, green sheets in the green sheet lamination method, extrusion compacts, roll compaction, and compacts in the powder hot pressing method.

[0039] In FIG. 4, the ceramic molded bodies 11 and 12 are divided into two members, but they may be three or more members depending on the design of the electrode-embedded member. For example, additives such as binders, plasticizers, and dispersants are appropriately added to and mixed with raw powder of AlN ceramics to prepare a slurry. Next, the granulated powder is granulated by a spray-drying method or the like. Next, the granulated powder is pressure-molded to form a plurality of ceramic molded bodies 11 and 12. Powder serving as a sintering aid may be added to the raw powder of ceramics as necessary.

[0040] The raw material powder of the AlN ceramics is preferably of high purity, preferably 96% or more, more preferably 98% or more, and the average particle size of the raw material powder of the AlN ceramics is preferably 0.1 μm or more and 1.0 μm or less.

[0041] The mixing method may be either wet or dry, and a mixer such as a ball mill or a vibration mill may be used. As a molding method, a known method such as uniaxial pressing or cold isostatic pressing (CIP) may be used. The method for forming the ceramic molded body is not limited to pressing, and may be, for example, green sheet lamination or casting, which may be appropriately degreased or further calcined to produce the ceramic molded body. After molding, the shape of the ceramic molded bodies 11 and 12 may be adjusted by machining.

[0042] Next, the ceramic molded bodies 11, 12 are degreased at a predetermined temperature or higher for a predetermined time or longer to produce a plurality of ceramic degreased bodies 21, 22. The ceramic molded bodies 11, 12 are heat treated at a temperature of, for example, 400° C. or higher and 800° C. or lower to become the ceramic degreased bodies 21, 22. The degreasing time is preferably 1 hour or longer and 120 hours or shorter. For the degreasing, An atmospheric furnace or a nitrogen atmosphere furnace can be used, but an atmospheric furnace is preferable in order to remove unnecessary components of the binder. As shown in FIG. 4(c), a recess 40 having a shape corresponding to the shape of the electrode 120 and the connection member 130 may be formed on one main surface (the surface to be joined with another ceramic degreased body 21) of the ceramic degreased body 22. The recess 40 may be provided on the ceramic degreased body 21 or on both. The machining may be performed on the ceramic molded body before degreasing. The electrode-embedded member 100 may be produced without the degreasing step.

[0043] In the electrode preparation step STEP 2, the electrode 120, the connection member 130 made of W or Mo, and the paste 32 containing W or Mo are prepared. The electrode preparation step STEP 2 can be performed in any order with respect to the compact formation step STEP 1. The electrode 120 is formed by foil, thin plate, wire, mesh, or the like of molybdenum or tungsten, or a porous body made of these materials, filling with paste, or printing.

[0044] The connection member 130 is made of W or Mo. The connection member 130 is prepared by processing it to a shape and thickness according to the design of the electrode-embedded member 100. The paste 32 containing W or Mo is a paste in which W or Mo powder and a binder are mixed. The average particle diameter D50 of the W or Mo powder is preferably 1 μm or more and 10 μm or less. The paste 32 containing W or Mo is preferably a paste in which the ratio of the W or Mo powder in the paste is 50 wt% or more and 90 wt% or less. Any binder may be used, but for example, ethyl cellulose can be used. The paste containing W or Mo is applied to a predetermined surface of the connection member 130, and becomes a porous layer 132 made of W or Mo by passing through a firing step STEP 5 described later. As a result, the connection member 130 is obtained in which the porous layer 132 made of W is formed on the predetermined surface or Mo.

[0045] In the paste application step STEP 3, paste 32 is applied to a predetermined area on the lower surface of connection member 130. The thickness of paste 32 is preferably 10 μm or more and 500 μm or less. The predetermined area is at least the area of ​​the surface of the lower surface of connection member 130 that is in direct contact with the ceramic degreased body, excluding the area where terminal hole 142 is drilled. As a result, a porous layer 132 made of W or Mo is formed in the area where paste 32 containing W or Mo is applied, and a porous layer made of W or Mo can be formed at the interface between connection member 130 and the ceramic sintered body.

[0046] The reason why the range where the terminal hole 142 is drilled may be excluded from the predetermined range is that when the terminal hole 142 is drilled, the porous layer 132 in that range does not contribute to suppressing the intrusion of oxygen. In other words, the porous layer 132 in that range does not contribute to improving the adhesion between the connection member 130 and the ceramic sintered body. In addition, when the terminal hole 142 is drilled, the porous layer 132 in that range may also be removed. On the other hand, the paste 32 may be applied to the entire lower surface of the connection member 130 because it is easier to apply it to the entire lower surface of the connection member 130. Furthermore, the paste 32 may be applied to the entire side surface of the connection member 130 because it is easier to apply it to the entire side surface of the connection member 130. As a result, the porous layer 132 made of W or Mo is formed on the side surface to which the paste 32 containing W or Mo is applied, and the porous layer 132 made of W or Mo can be formed at the interface between the side surface of the connection member 130 and the ceramic sintered body.

[0047] The paste 32 containing W or Mo can also be used to improve the reliability of the electrical connection between the connection member 130 and the electrode 120. Therefore, the paste 32 may be applied to the upper surface of the connection member 130. Therefore, the paste 32 may be applied to the entire surface including the upper and lower surfaces of the connection member 130, or the upper and side surfaces of the connection member 130. In this way, one type of paste 32 containing W or Mo can be given multiple roles, and costs can be reduced compared to the case where different pastes are applied to the upper and lower surfaces. Furthermore, the paste 32 containing W or Mo may be applied to the connection member 130 by dipping. In this case, the process is simplified and costs can be further reduced. That is, the paste application step STEP 3 also includes application by dipping.

[0048] In the precursor forming step STEP 4, the prepared electrode 120, the connection member 130 coated with the paste 32, and a plurality of molded bodies are combined to form an electrode embedding member precursor 50 formed in a flat plate shape and in which the electrode 120 and the connection member 130 are embedded. In FIG. 4, ceramic degreased bodies 21 and 22 are used as the plurality of molded bodies. In the precursor forming step STEP 4, the electrode embedding member precursor 50 may also be formed by a powder hot pressing method. In that case, the molded body formed in the precursor forming step STEP 4, the prepared electrode 120, and the connection member 130 coated with the paste 32 are combined, and a molded body formed by adding raw material powder is further combined to form an electrode embedding member precursor 50 formed in a flat plate shape and in which the electrode 120 and the connection member 130 are embedded.

[0049] In the firing step STEP 5, the formed electrode-embedded member precursor 50 is uniaxially pressurized and fired in a direction perpendicular to one of the main surfaces of the electrode-embedded member precursor 50 to fire the electrode-embedded member 100. The pressure is preferably 1 MPa or more. The firing temperature is preferably 1500°C or more and 2000°C or less. The firing time is preferably 1 hour or more and 12 hours or less. The firing atmosphere is, for example, a nitrogen or inert gas atmosphere, but may also be a vacuum atmosphere. As a result, the multiple molded bodies are sintered to become ceramic sintered bodies, which are integrated to obtain the electrode-embedded member 100 in which the electrodes 120 and the connection members 130 are embedded.

[0050] Thereafter, if necessary, a terminal hole 142 is provided in the fired electrode-embedded member 100 to expose the surface of the connection member 130. At this time, if a porous layer 132 is formed on the surface of the connection member 130, it is preferable to also remove the porous layer 132 in the range of the terminal hole 142. This can increase the reliability of the electrical connection between the connection member 130 and the terminal 140. The terminal hole 142 is made smaller than the connection member 130. For example, it is preferable that the diameter of the terminal hole 142 is 90% or less of the diameter of the connection member 130.

[0051] Then, the terminal 140 is connected to the exposed connection member 130 with brazing material or the like. The terminal 140 can be made of Ni or the like. The brazing material can be Au brazing, Ni brazing, or the like. One or more buffer members 144 made of W, Mo, Kovar, or the like may be disposed between the connection member 130 and the terminal 140, and brazed.

[0052] In this manner, a porous layer 132 made of W or Mo can be formed at the interface between the connecting member 130 and the ceramic sintered body, and the intrusion of oxygen from between the connecting member 130 and the ceramic sintered body can be suppressed, making it possible to manufacture an electrode-embedded member 100 that can suppress deterioration of the connecting member 130. As a result, the reliability of the base 110, particularly the insulating layer 114, can be improved, and the product life of the electrode-embedded member 100 can be made longer than that of conventional products.

[0053] A ceramic calcined body preparation step may be provided between the molded body preparation step STEP 1 and the precursor formation step STEP 4. When the ceramic calcined body preparation step is provided, the ceramic degreased body is calcined at a temperature of 1200°C to 1700°C to prepare a ceramic calcined body. This makes it possible to improve the dimensional accuracy of the outer shape of the electrode-embedded member and the embedding positions of the electrodes and the connecting members. The calcination time is preferably 0.5 hours to 12 hours. The calcination atmosphere is preferably a nitrogen or inert gas atmosphere, but may be a vacuum atmosphere. When the calcined body preparation step is provided, machining may be performed after the calcined body preparation step.

[0054] [Examples and Comparative Examples] Example 1 Ceramic raw material powder, mainly composed of AlN with 5wt% Y2O3 added, was used for CIP molding (pressure 1ton / cm 2 ) to obtain an ingot of a green body. This was machined to form a ceramic green body with a diameter of 320 mm and a thickness of 5 mm, and a ceramic green body with a diameter of 320 mm and a thickness of 40 mm. A recess with a diameter of 295 mm and a depth of 0.1 mm was provided on one side of the 40 mm thick ceramic green body, sharing the center of the green body, for accommodating an electrode. Furthermore, a recess with a diameter of 8 mm and a depth of 0.2 mm was provided at a predetermined position for forming a terminal, for accommodating a connecting member.

[0055] Next, the ceramic molded body was degreased at 550°C for 4 hours to prepare a ceramic degreased body. Next, a molybdenum mesh (wire diameter 0.1 mm, plain weave, mesh size #50) with a diameter of 294 mm was cut into a predetermined shape to prepare an electrode. Also, a connecting member with a size of φ7 mm x 0.2 mmt was prepared from a W pellet. Next, a binder was mixed with W powder to prepare a paste containing 70 wt% W powder. Next, the paste was applied to both sides and the side of the connecting member with a thickness of 100 μm, and the connecting member was placed in the recess of the ceramic degreased body with a recess. Then, an electrode was placed on it and sandwiched with the other ceramic degreased body to prepare an electrode-embedded member precursor.

[0056] Next, the electrode-embedded member precursor was placed in a hot press furnace, and uniaxial hot press sintered at 1900° C. for 2 hours while applying a force of 4 MPa in a direction perpendicular to the main surface (mounting surface) of the electrode-embedded member precursor. In this manner, the electrode-embedded member was sintered.

[0057] After that, the entire surface was ground and polished to a total thickness of 24 mm and an insulating layer thickness of 1.4 mm. Then, a flat-bottom hole with a hole diameter of φ5 mm was drilled from the back surface (lower surface) of the base to the terminal position, reaching the connecting member. In this way, the sample of Example 1 was produced. Note that the samples of the Example and Comparative Example were samples to confirm whether the oxidation of the connecting member would progress in the subsequent test, so the terminals were not connected.

[0058] Example 2 A sample of Example 2 was produced under the same conditions as Example 1, except that the connection members were produced from Mo pellets and the paste material was changed from W powder to Mo powder.

[0059] Comparative Example 1 In Comparative Example 1, the connection member was not coated with a paste containing W. The sample of Comparative Example 1 was produced under the same conditions as in Example 1 except for that.

[0060] [Performance evaluation] (Check the interface and whether or not the connecting parts are oxidized) The prepared sample was placed in a chamber so that air could pass through the terminal holes, and was kept at 550°C for 40 hours. The sample was then cut along a vertical cross section passing through the center of the connection member, and the cross sections of the electrodes and connection members were exposed and polished, after which they were examined using SEM images and analyzed for composition using EDX. In addition, the cross section was observed at a magnification of 500 times to confirm whether a porous layer containing pores of a specified size was formed at the interface between the connection member and the sintered ceramic body. In addition, it was confirmed whether a boundary layer of 1 μm or more in thickness, defined by a clear boundary line, was formed at the interface between the connection member and the sintered ceramic body. In addition, it was confirmed whether oxygen was detected in the composition analysis using EDX when a boundary layer was formed.

[0061] In the samples of Example 1 and Example 2, it was confirmed by checking the SEM images that a porous layer was formed at the interface between the connection member and the ceramic sintered body. In addition, in the samples of Example 1 and Example 2, it was confirmed by checking the SEM images that a boundary layer was not formed at the interface between the connection member and the ceramic sintered body. On the other hand, in the sample of Comparative Example 1, it was confirmed by checking the SEM images that a porous layer was not formed at the interface between the connection member and the ceramic sintered body. In addition, it was confirmed that a boundary layer different from the inside of the connection member was formed at the interface between the connection member and the ceramic sintered body.

[0062] The boundary layer of the connecting member of the sample of Comparative Example 1 was found to be an oxide layer made of an oxide of W, since oxygen was confirmed by composition analysis by EDX. This also revealed that no boundary layer was formed in Example 1 and Example 2, and therefore no oxide layer was formed.

[0063] As a result, it was confirmed that the electrode-embedded member of the present invention can suppress the intrusion of oxygen from between the connection member and the ceramic sintered body, and can suppress the deterioration of the connection member. As a result, it is believed that the product life of the electrode-embedded member can be made longer than that of conventional products. It was also confirmed that the manufacturing method of the present invention can manufacture such an electrode-embedded member.

[0064] The present invention is not limited to the above-described embodiment, and it goes without saying that various modifications and equivalents are included within the spirit and scope of the present invention. In addition, the structure, shape, number, position, size, etc. of the components shown in each drawing are for convenience of explanation and may be changed as appropriate. [Explanation of symbols]

[0065] 11, 12 Ceramic molding 21, 22 Ceramic degreased body 32 Paste 40 Recess 50 Electrode embedding material precursor 100 Electrode embedding member 110 Base 112 Placement surface 114 Insulating layer 120 electrodes 130 Connection member 132 Porous Layer 140 Terminals 142 Terminal hole 144 Cushioning material

Claims

1. An electrode embedding member, A substrate formed in a flat plate shape from a ceramic sintered body mainly composed of AlN; An electrode embedded in the substrate; a connection member made of W or Mo and electrically connected to the electrode and embedded in the base, 2. An electrode-embedding member, comprising: a porous layer made of W or Mo formed on the interface between the lower surface of the connection member and the ceramic sintered body.

2. 2. The electrode-embedding member according to claim 1, wherein the porous layer is formed on an upper surface and a side surface of the connection member.

3. 2. The electrode-embedding member according to claim 1, wherein the porous layer is formed on an upper surface of the connection member.

4. A method for manufacturing an electrode-embedded member, comprising the steps of: a molded body preparation step of preparing a plurality of molded bodies formed of ceramics containing AlN as a main component; an electrode preparation step of preparing an electrode, a connection member made of W or Mo, and a paste containing W or Mo; a paste applying step of applying the paste to at least a predetermined surface of the lower surface of the connection member; a precursor forming step of combining the electrodes, the connection members to which the paste has been applied, and the plurality of molded bodies to form a plate-shaped electrode-embedded member precursor in which the electrodes and the connection members are embedded; and a firing step of firing the electrode-embedded member precursor under uniaxial pressure in a direction perpendicular to one main surface of the electrode-embedded member precursor to fire the electrode-embedded member.

Images