Electrode embedding member

Abstract

To provide an electrode embedding member that can restrain intrusion of oxygen through a terminal hole and can restrain oxidation of a connection member.SOLUTION: An electrode embedding member 100 includes a base 110 formed in a flat-plate shape of a ceramic sintered body, an electrode 120 embedded in the base 110, a connection member 130 electrically connected to the electrode 120 and embedded in the base 110, a terminal hole 142 provided in the base 110, a terminal 140 electrically connected to the connection member 130 and disposed in the terminal hole 142, and a sealing member 150 that seals the terminal hole 142. The sealing member 150 is made of amorphous glass or crystallized glass having a glass softening point of 900°C or less and a CTE of 10 ppm or less, and continuously covers a portion of the side surface of the terminal 140 to a portion of the side surface of the terminal hole 142.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an electrode-embedding member. [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 technology for a holder for a workpiece, which includes a ceramic base having an electric circuit and for holding a workpiece, a cylindrical member having one end connected to the ceramic base, a power supply conductive member electrically connected to the electric circuit on the inner periphery of the cylindrical member, and a sealing member located on the inner periphery of the cylindrical member, arranged to surround the periphery of the joint between the electric circuit and the power supply conductive member, and connected to the ceramic base, wherein the sealing member isolates the joint between the electric circuit and the power supply conductive member from the space on the outer periphery of the sealing member. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2006-179897 A Summary of the Invention [Problem to be solved by the invention]

[0005] In conventional electrode-embedding members in which a connecting member is embedded, oxygen may enter through the terminal holes, causing the connecting member to oxidize over long-term use. When the connecting member oxidizes, there is a risk of internal breakage of the connecting member or poor electrical continuity due to poor contact between the connecting member and the terminal or buffer member. Furthermore, when the connecting member oxidizes, the volume of the connecting member expands. If the electrode-embedding member is continued to be used in such a state, the adhesion between the connecting member and the ceramic sintered body may be impaired. Therefore, an electrode-embedding member capable of suppressing the oxidation of such connecting members has been desired.

[0006] The technology described in Patent Document 1 creates a sealing member made of ceramics and bonds it with glass to isolate the bond between the electric circuit and the power supply conductive member from the space on the outer periphery of the sealing member. However, the technology described in Patent Document 1 requires the sealing member to be separately manufactured, which makes the structure complicated and increases costs.

[0007] The inventors discovered that by sealing the terminal holes with a sealing member made of glass with appropriate properties, it is possible to prevent oxygen from entering through the terminal holes and to prevent oxidation of the connecting members, and thus completed the present invention.

[0008] That is, the present invention has been made in consideration of the above circumstances, and has an object to provide an electrode-embedding member that can suppress the intrusion of oxygen through the terminal holes and can suppress oxidation of the connection members more than ever before. [Means for solving the problem]

[0009] (1) In order to achieve the above object, the electrode embedding member of the present invention employs the following means: That is, the electrode embedding member of the application example of the present invention is an electrode embedding member comprising: a base formed in a flat plate shape from a ceramic sintered body, an electrode embedded in the base, a connection member electrically connected to the electrode and embedded in the base, a terminal hole provided in the base, a terminal electrically connected to the connection member and disposed in the terminal hole, and a sealing member that seals the terminal hole, the sealing member being made of amorphous glass or crystallized glass having a glass softening point of 900° C. or less and a CTE of 10 ppm or less, and continuously covering a portion of a side surface of the terminal to a portion of a side surface of the terminal hole.

[0010] In this way, by continuously covering a part of the side surface of the terminal to a part of the side surface of the terminal hole with the sealing member, it is possible to block oxygen to the connection member in the terminal hole and prevent oxidation of the connection member. In addition, by making the sealing member from amorphous glass or crystallized glass with a glass softening point of 900°C or less and a CTE of 10 ppm or less, it is possible to reduce the risk of the glass shrinking during cooling and creating an opening through which oxygen can enter the sealing member.

[0011] (2) Furthermore, the electrode-embedded member of the application example of (1) above further includes a shaft formed in a cylindrical shape from a sintered ceramic body and joined to an underside of the base on which the terminal hole is provided, and the sealing member continuously covers a portion of the side surface of the terminal hole, through the underside, and up to a portion of the side surface of the shaft on the inner diameter side.

[0012] In this way, by continuously covering with the sealing material part of the side of the terminal, part of the side of the terminal hole, the underside of the base, and part of the side of the inner diameter side of the shaft, it is possible to better block oxygen to the connecting member in the terminal hole, and to better prevent oxidation of the connecting member.

[0013] (3) In the electrode-embedding member according to the application example of (1) or (2) above, the glass softening point of the sealing member is 500° C. or higher.

[0014] This allows the electrode-embedded member to be used in medium-temperature applications at around 500°C.

[0015] (4) In the electrode-embedding member according to any one of the application examples of (1) to (3) above, the sealing member contains at least one component of ZnO or B2O3.

[0016] This makes it possible to specifically prepare amorphous glass or crystallized glass that satisfies the above conditions.

[0017] (5) In the electrode-embedding member according to the application example of (4) above, the total content of the ZnO and B2O3 components in the sealing member is 70 wt % or less.

[0018] This makes it easy to use crystallized glass for the sealing member. By making the sealing member out of crystallized glass, the strength of the sealing member itself can be increased, the corrosion resistance can be improved, and it becomes easier to adjust the CTE over a wide range.

[0019] (6) In the electrode-embedding member according to any one of the application examples of (1) to (5) above, the sealing member has a CTE of 4.5 ppm or less.

[0020] This can further reduce the risk of the glass shrinking during cooling and creating openings in the sealing member through which oxygen can penetrate.

[0021] (7) In the electrode-embedding member according to any one of the application examples of (1) to (6) above, the absolute value of the difference between the CTE of the sealing member and the CTE of the base is 1.5 ppm or less.

[0022] This makes it possible to prevent the sealing member from peeling off due to the difference in CTE between the base and the sealing member, even when the electrode-embedded member is used at high temperatures. Effect of the Invention

[0023] According to the electrode-embedded member of the present invention, the terminal holes in the electrode-embedded member after terminal connection can be sealed with the sealing member, reducing the risk of the glass shrinking during cooling and creating openings through which oxygen can penetrate into the sealing member. [Brief description of the drawings]

[0024] [Figure 1] 1 is a schematic cross-sectional view showing an example of an electrode-embedded member according to a first embodiment of the present invention. [Diagram 2] 2 is a partially enlarged view of the vicinity of a terminal hole of the electrode-embedding member of FIG. 1. [Diagram 3] FIG. 6 is a schematic cross-sectional view showing an example of an electrode-embedded member according to a second embodiment of the present invention. [Figure 4] 4 is a partially enlarged view of the vicinity of a terminal hole of the electrode-embedding member of FIG. 3. [Diagram 5] 1 is a table showing characteristics and test results of electrode-embedded members of Examples and Comparative Examples. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] 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.

[0026] [First embodiment] (Configuration of electrode embedding member) An electrode-embedded member according to a first embodiment of the present invention will be described with reference to Fig. 1 and Fig. 2. Fig. 1 is a schematic cross-sectional view showing one example of an electrode-embedded member according to the first embodiment of the present invention. Fig. 2 is a partially enlarged view of the vicinity of a terminal hole of the electrode-embedded member of Fig. 1. An electrode-embedded member 100 according to this embodiment includes a base 110, an electrode 120, a connection member 130, a terminal hole 142, a terminal 140, and a sealing member 150.

[0027] The base 110 is made of a ceramic sintered body and is formed into a substantially flat plate shape. The base 110 may be in various shapes such as a substantially circular plate shape, a polygonal plate shape, or an elliptical plate shape. The base 110 may be made of a ceramic sintered body such as aluminum nitride, aluminum oxide, silicon carbide, or silicon nitride. Of these, the base 110 is preferably made of aluminum nitride.

[0028] The electrode 120 is embedded in the base 110. The electrode 120 is used, for example, as a high-frequency electrode, a heater electrode, or an electrostatic attraction electrode. The electrode 120 can be formed of a mesh, a foil, a coil, or a thin film. The electrode 120 can have various shapes depending on the design of the electrode-embedded member 100. The electrode 120 is preferably formed of Mo, W, or an alloy containing these. The base 110 may be provided with a plurality of electrodes 120.

[0029] 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 preferably made of Mo, W, or an alloy containing these.

[0030] 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 an increased risk of the connection member 130 being 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 an increased risk of a defect in the adhesion between the base 110 and the connection member 130 due to the difference in the contraction rate during firing and the difference in the thermal expansion rate during use between the base 110 and the ceramic of the base 110.

[0031] 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, 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.

[0032] The terminal holes 142 are drilled from the lower surface 114 of the base 110. The terminal holes 142 are drilled to a depth that exposes the connection members 130.

[0033] The sealing member 150 seals the terminal hole 142. The sealing member 150 continuously covers from a part of the side surface of the terminal 140 to a part of the side surface of the terminal hole 142. In this way, by continuously covering from a part of the side surface of the terminal 140 to a part of the side surface of the terminal hole 142 with the sealing member 150, oxygen can be blocked to the connection member 130 in the terminal hole 142, and oxidation of the connection member 130 can be prevented. The sealing member 150 continuously covers from a part of the side surface of the terminal 140 to a part of the side surface of the terminal hole 142 means that no opening or the like through which oxygen can enter and communicate with the inside of the sealed terminal hole 142 is formed in the range covered by the sealing member 150. The thickness of the sealing member 150 in the terminal hole 142 direction is preferably 2 mm or more. The sealing member 150 may fill the entire terminal hole 142 when viewed from the bottom surface 114. The sealing member 150 may not be in contact with the connection member 130. The terminal hole 142 sealed by the sealing member 150 may contain a gap therein.

[0034] The sealing member 150 is made of amorphous glass or crystallized glass having a glass softening point of 900° C. or less and a CTE of 10 ppm or less. Since the sealing member 150 is made of amorphous glass or crystallized glass having a glass softening point of 900° C. or less and a CTE of 10 ppm or less, the terminal hole 142 of the electrode-embedded member 100 after the terminal 140 is connected can be sealed with the sealing member 150, and the risk of the glass shrinking during cooling and the occurrence of an opening through which oxygen can enter the sealing member 150 can be reduced.

[0035] In this specification, the CTE (coefficient of thermal expansion) is the average linear expansion coefficient (ppm / °C) from 50°C to 350°C. The CTE can be measured by separately preparing a test piece conforming to JIS R3102-1995 and using a thermal expansion measuring device. The glass softening point can be measured by a differential thermal analyzer. The sealing member 150 is preferably made of crystallized glass. By forming the sealing member 150 from crystallized glass, the strength of the sealing member 150 itself can be increased, the corrosion resistance is improved, and it becomes easy to adjust the CTE over a wide range.

[0036] When the electrode-embedded member 100 has a plurality of terminal holes 142, it is sufficient that at least one of the terminal holes 142 is sealed with the sealing member 150 according to the configuration of the present invention. A plurality of the terminal holes 142 or all of the terminal holes 142 may be sealed according to the configuration of the present invention.

[0037] The glass softening point of the sealing member 150 is preferably 500° C. or higher. This allows the electrode-embedded member 100 to be used in medium-temperature applications at around 500° C. In addition, the glass softening point of the sealing member 150 is more preferably 600° C. or higher.

[0038] The sealing member 150 preferably contains at least one component of ZnO or B2O3. This allows for the specific construction of amorphous glass or crystallized glass having the above-mentioned glass softening point and CTE conditions, making it easy to adjust the CTE and glass softening point. When the sealing member 150 contains at least one component of ZnO or B2O3, the total content of the ZnO and B2O3 components in the sealing member 150 is preferably 70 wt% or less. This makes it easy to make the sealing member 150 a crystallized glass.

[0039] The CTE of the sealing member 150 is preferably 4.5 ppm or less, which can further reduce the risk of the glass shrinking during cooling and creating an opening in the sealing member through which oxygen can penetrate.

[0040] The absolute value of the difference between the CTE of the sealing member 150 and the CTE of the base 110 is preferably 1.5 ppm or less. This makes it possible to prevent the sealing member 150 from peeling off due to the difference in CTE between the base 110 and the sealing member 150, even when the electrode-embedded member 100 is used at high temperatures.

[0041] The electrode embedding member 100 may be provided with pin-shaped protrusions, annular protrusions, lift pin holes, vent holes, shafts, and the like (not shown).

[0042] [Second embodiment] (Configuration of electrode embedding member) An electrode-embedded member according to a second embodiment of the present invention will be described with reference to Figs. 3 and 4. Fig. 3 is a schematic cross-sectional view showing one example of an electrode-embedded member according to the second embodiment of the present invention. Fig. 4 is a partially enlarged view of the vicinity of the terminal hole of the electrode-embedded member of Fig. 3. An electrode-embedded member 100 according to this embodiment includes a base 110, an electrode 120, a connection member 130, a terminal hole 142, a terminal 140, a sealing member 150, and a shaft 160. The basic configuration of the electrode-embedded member 100 other than the shaft 160 is the same as described above.

[0043] The shaft 160 is formed in a cylindrical shape from a ceramic sintered body, and is joined via a joining surface to a predetermined position on the lower surface 114 of the base 110 where the terminal hole 142 is provided. The shaft 160 supports the electrode-embedded member 100. The joining may be solid-state joining or joining using a joining material. The shaft 160 is preferably formed from a ceramic sintered body having the same main component as the base 110 of the electrode-embedded member 100. The shaft 160 is preferably cylindrical.

[0044] It is preferable that the sealing member 150 continuously covers from a part of the side surface of the terminal hole 142, further via the lower surface 114, to a part of the side surface on the inner diameter side of the shaft 160. In this way, by continuously covering with the sealing member 150 from a part of the side surface of the terminal 140, through a part of the side surface of the terminal hole 142, through the lower surface 114 of the base 110, to a part of the side surface on the inner diameter side of the shaft 160, it is possible to more effectively block the intrusion of oxygen into the connection member 130 in the terminal hole 142, and to more effectively prevent the oxidation of the connection member 130. The sealing member 150 continuously covers from a part of the side surface of the terminal hole 142, further via the lower surface 114, to a part of the side surface on the inner diameter side of the shaft 160 means that no opening or the like through which oxygen can intrude that communicates with the inside of the sealed terminal hole 142 is formed in the range covered by the sealing member 150.

[0045] Note that, although FIG. 3 shows an example of an electrode embedding member in which the electrode embedding member 100 of FIG. 1 is combined with the shaft 160, the electrode embedding member 100 according to this embodiment may be a combination of an electrode embedding member 100 of another shape and a shaft 160.

[0046] In the electrode embedding member 100 of the present invention, the sealing member 150 can suppress the intrusion of oxygen from the terminal hole 142, and can suppress oxidation of the connection member 130. As a result, it is possible to reduce the risk of internal fracture of the connection member 130 due to oxidation of the connection member 130, and of poor conduction due to poor contact between the connection member 130 and the terminal 140 or the buffer member 144. It is also possible to reduce the risk of defects such as peeling of the base 110 caused by expansion of the connection member 130. In particular, it is possible to suppress the effect on the insulating layer of the base 110 on the upper surface 112 of the electrode 120. As a result of these, it is possible to increase the reliability of the electrode embedding member 100.

[0047] [Method of manufacturing electrode-embedded members] Next, a method for manufacturing an electrode-embedded member according to an embodiment of the present invention will be described. The electrode-embedded member according to an embodiment of the present invention is manufactured, for example, by a powder hot pressing method. The powder hot pressing method is a method in which ceramic raw material powder and a predetermined electrode are alternately stacked to embed the electrodes inside the ceramic, and then uniaxial hot pressing and firing the resulting material. By employing the powder hot pressing method, the member can be manufactured in a short period of time. Note that the manufacturing method is not limited to this method, and may be, for example, a molded body hot pressing method disclosed in Japanese Patent No. 6148845, a green sheet lamination method, a CIP molding method, or other conventional manufacturing methods.

[0048] For example, additives such as sintering aids, binders, plasticizers, and dispersants are appropriately added to and mixed with ceramic powder to prepare ceramic raw material powder (slurry), and the granulated powder is granulated by a spray-drying method or the like. For example, when AlN is used as the raw material, 6 wt% or less of Y2O3 may be added to the AlN ceramic raw material powder as a sintering aid to granulate the granulated powder. 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 the raw ceramic powder, aluminum nitride, aluminum oxide, silicon carbide, silicon nitride, etc. are used.

[0049] The ceramic powder is preferably of high purity, and the purity is preferably 96% or more, more preferably 98% or more. The average particle size of the ceramic powder varies depending on the type of ceramic powder used as the raw material, but for example, when AlN is used as the raw material, the average particle size is preferably 0.1 μm to 1.0 μm, and more preferably 0.3 μm to 0.8 μm.

[0050] The material of the electrode embedded in the ceramic sintered compact is preferably Mo, W, or an alloy thereof. The electrode can be formed of a mesh, foil, coil, or thin film of these materials. For example, an Mo mesh (wire diameter 0.1 mm, 50 mesh, plain weave) is cut into a predetermined shape to form an electrode. The outer diameter of the electrode is smaller than the outer diameter of the base so that it is not exposed from the outer surface of the base. A connection member for connecting to an external power source is preferably embedded at the same time as the electrode.

[0051] For sintering, uniaxial hot press sintering or atmospheric sintering can be used. In uniaxial hot press sintering, a granulated powder that forms the base is filled into a bottomed carbon mold, and an electrostatic adsorption electrode cut into a predetermined shape after uniaxial pressing is placed on the compact. The same granulated powder is filled on top of it, a carbon punch is placed on it, and after molding, it is sintered under predetermined sintering conditions. For example, when AlN is used as the raw material, it is preferable to perform hot press sintering under temperature conditions of 1700°C to 2000°C, pressure conditions of 1 MPa to 20 MPa, and for 0.1 hours to 20 hours.

[0052] After firing, the electrode-embedded member is subjected to processing of the front and back surfaces, formation of terminal holes, and grinding and polishing into a predetermined shape. Forming methods include blasting, milling, laser processing, etc. Also, multiple pin-shaped protrusions, annular protrusions, etc. may be formed depending on the design of the electrode-embedded member.

[0053] When joining the shaft, the granulated powder is molded into a predetermined shape and fired to sinter the shaft. The shaft is preferably formed of a ceramic sintered body having the same main component as the base of the electrode-embedded member. The shaft is preferably cylindrical. The sintered shaft is joined to a predetermined position on the lower surface of the base of the electrode-embedded member, the surface of which has been processed. The joining may be solid-state joining or joining using a joining material.

[0054] After processing the surface, a terminal is connected to the terminal hole with brazing material or the like to establish electrical continuity with the connection member. The terminal may be made of Ni or the like. The brazing material may be Au brazing material or the like. When joining a shaft, it is preferable to connect the terminal after joining the shaft.

[0055] The terminal holes are then sealed with a sealing member. Glass having predetermined properties is prepared in advance as the sealing member. The sealing member is preferably prepared as glass frit, a molded body obtained by solidifying glass frit into a predetermined shape, or a paste containing glass frit and an organic binder. The prepared sealing member is filled at least to a predetermined position in the terminal holes, and heat-treated at a temperature higher than the glass softening point, thereby sealing the terminal holes.

[0056] At this time, to prevent the brazing material from flowing and causing poor connection, the glass softening point of the sealing member is set to 900° C. or less. Also, to prevent the glass from shrinking during cooling and causing peeling or openings, the CTE of the sealing member is set to 10 ppm or less.

[0057] In this manner, the connection member 130 exposed through the terminal hole 142 is not exposed to oxygen, making it possible to manufacture an electrode-embedding member 100 that can suppress oxidation of the connection member 130. As a result, the influence on the insulating layer of the base 110, particularly the upper surface 112, can be suppressed.

[0058] [Examples and Comparative Examples] Example 1 5wt% of Y2O3 was added as a sintering aid to the AlN raw powder, and binders, dispersants, etc. were added appropriately and mixed to prepare a slurry, which was then granulated by spray drying. In addition, plain-woven Mo mesh with a wire diameter of 0.1mm and mesh size #50 was cut into a specified shape to prepare electrodes. In addition, a connecting member made of tungsten with a diameter of 10mm and a thickness of 0.5mm was prepared.

[0059] Next, the carbon mold was filled with granulated powder, and a molded body with a diameter of φ100 mm and a thickness of t10 mm was produced by uniaxial pressing. Next, an electrode was placed on the surface of the molded body, a connecting member was placed at the center of the electrode, and granulated powder was further filled to embed the connecting member and the electrode. Then, the molded body was uniaxially hot-pressed in a nitrogen atmosphere at a firing temperature of 1850°C and a hot-press pressure of 5 MPa. The firing time was 2 hours. The obtained ceramic sintered body was machined to have a diameter of φ100 mm, a thickness of t20 mm, and a distance from the upper surface to the electrode of 1.5 mm. In addition, the surface roughness Ra of the position to be the joint of the shaft was set to 0.1 μm or less. Next, a terminal hole was drilled at the position where the connecting member was embedded on the lower surface, and a part of the connecting member was exposed.

[0060] Separately, granulated powder was made using AlN raw powder to which no sintering aid was added, and a ceramic molded body was formed by CIP so that the shape after firing would be a hollow cylinder. This was degreased at 550°C for 12 hours to produce a ceramic degreased body. The ceramic degreased body was fired at 1900°C for 5 hours at normal pressure to fire the shaft. The surface roughness Ra of the end face of the joint of the shaft was set to 0.1 μm or less.

[0061] Then, a shaft was placed at the joint of the base, and the shaft was heated at 1800°C for 1 hour while applying a force of 1 MPa in the direction perpendicular to the mounting surface to bond the shaft. Next, a W pellet of φ5mm×t2mm and a Kovar pellet of φ5mm×t2mm were inserted in order into the terminal hole as a buffer member, and a nickel pellet of 5mm diameter and 50mm length was placed on top of the W pellet as a power supply terminal. These were brazed in a vacuum at 1000°C using a brazing material made of Au-Ni-Ti. The end of the power supply terminal exposed to the outside was threaded to connect it to the jig of a tensile tester for the tensile test described later.

[0062] Then, glass frit was inserted into the terminal hole, and heat treatment was performed at 700°C to seal the terminal hole. The main components of the glass used were ZnO, Bi2O3, and B2O3, in descending order of weight percentage (wt%). The glass softening point of the glass of Example 1, measured separately by differential thermal analysis (DTA), was 516°C. The CTE of the glass of Example 1, measured by a thermal expansion measuring device, was 4.2 ppm. The CTE of AlN constituting the substrate was 4.2 ppm. In this way, two electrode-embedded members of Example 1 were produced.

[0063] Example 2 In the electrode embedding member of Example 2, the type of glass used to seal the terminal hole was changed to one whose main components were SiO2 and PbO. Otherwise, the electrode embedding member of Example 2 was produced under the same conditions as in Example 1. The glass softening point of the glass of Example 2 was 829°C, and the CTE was 4.0 ppm.

[0064] Example 3 In the electrode embedding member of Example 3, the type of glass sealing the terminal hole was changed to one whose main components were SiO2, BaO, and ZnO. Otherwise, the electrode embedding member of Example 3 was produced under the same conditions as in Example 1. The glass softening point of the glass of Example 3 was 808°C, and the CTE was 3.5 ppm.

[0065] Example 4 In the electrode-embedding member of Example 4, the type of glass sealing the terminal hole was changed to one whose main components were ZnO, B2O3, and SiO2, and the glass was continuously covered up to a predetermined position on the side of the inside of the shaft. Otherwise, the electrode-embedding member of Example 4 was produced under the same conditions as Example 1. The glass softening point of the glass of Example 4 was 665°C, and the CTE was 3.7 ppm.

[0066] Example 5 In the electrode embedding member of Example 5, the type of glass sealing the terminal hole was changed to one whose main components were ZnO, B2O3, and SiO2. Otherwise, the electrode embedding member of Example 5 was produced under the same conditions as in Example 1. The glass softening point of the glass of Example 5 was 656°C, and the CTE was 4.3 ppm.

[0067] Example 6 In the electrode embedding member of Example 5, the type of glass sealing the terminal hole was changed to one whose main components were Bi2O3, ZnO, and B2O3. Otherwise, the electrode embedding member of Example 6 was produced under the same conditions as in Example 1. The glass softening point of the glass of Example 6 was 589°C, and the CTE was 7.6 ppm.

[0068] Comparative Example 1 The electrode-embedding member of Comparative Example 1 was produced under the same conditions as those of Example 1, except that the terminal hole was not sealed in the electrode-embedding member of Comparative Example 1.

[0069] Comparative Example 2 In the electrode embedding member of Comparative Example 2, the type of glass sealing the terminal hole was changed to one whose main components were SiO2, Al2O3, and CaO. Otherwise, the electrode embedding member of Comparative Example 2 was produced under the same conditions as in Example 1. The glass softening point of the glass of Comparative Example 2 was 931°C, and the CTE was 4.5 ppm.

[0070] Comparative Example 3 In the electrode embedding member of Comparative Example 3, the type of glass sealing the terminal hole was changed to one whose main components were Bi2O3, ZnO, and B2O3. Otherwise, the electrode embedding member of Comparative Example 3 was produced under the same conditions as in Example 1. The glass softening point of the glass of Comparative Example 3 was 414°C, and the CTE was 10.7 ppm.

[0071] (Evaluation test A (tensile test after heat load at 400℃)) One of the electrode-embedded members of the embodiment and the comparative example was mounted in a chamber, and an external power source was connected to the terminal. A temperature evaluation substrate with a black body surface was placed on the mounting surface of the electrode-embedded member, and the external power source was controlled so that the temperature of the temperature evaluation substrate became 400°C. After 100 hours had elapsed in this state, the electrode-embedded member was taken out of the chamber. The base of the electrode-embedded member was fixed, and the terminal was fixed to the jig of a tensile tester (Shimadzu Corporation Autograph). The terminal was then pulled in the vertical direction to measure the tensile strength. If the tensile strength was 200 MPa or more, it was evaluated as ◎ (excellent), if it was 100 to 200 MPa, it was evaluated as ◯ (good), and if it was less than 100 MPa, it was evaluated as × (not suitable).

[0072] (Evaluation test B (tensile test after heat load at 600℃)) The other electrode-embedded members of the example and the comparative example were mounted in a chamber, and an external power source was connected to the terminal. A temperature evaluation board was placed on the mounting surface of the electrode-embedded member, and the external power source was controlled so that the temperature of the temperature evaluation board was 600°C. After 100 hours had elapsed in this state, the electrode-embedded members were removed from the chamber. Then, a tensile test was performed in the same manner as above. The evaluation was also performed in the same manner.

[0073] (Evaluation Results) FIG. 5 is a table showing the glass properties, sealing locations, and evaluation results of evaluation test A or evaluation test B of the examples and comparative examples. Examples 1 to 6 were all rated as excellent in evaluation test A. In comparison, Comparative Examples 1 to 3 were all rated as unsuitable in evaluation test A. This confirmed that when the sealing member is made of amorphous glass or crystallized glass with a glass softening point of 900° C. or less and a CTE of 10 ppm or less, and covers at least a part of the side surface of the terminal to a part of the side surface of the terminal hole continuously, the tensile strength after heat load is stronger than that of the comparative examples that do not satisfy this. In other words, it was confirmed that the electrode embedding members of Examples 1 to 6 make the surface of the connection member less susceptible to oxidation.

[0074] In Comparative Example 1, it is presumed that the surface of the connection member was oxidized and became a source of fracture, resulting in a decrease in strength. In Comparative Example 2, it is presumed that the glass softening point was high and the glass was not sufficiently fluidized at the heat treatment temperature, resulting in insufficient airtightness. It is presumed that this caused the surface of the connection member to oxidize and the strength to decrease. In Comparative Example 3, it is presumed that the CTE was too large, resulting in an opening in the glass during cooling after glass sealing or cooling after a heat load test. It is presumed that this caused the surface of the connection member to oxidize and the strength to decrease.

[0075] In Example 1, it is believed that the heat load applied in Evaluation Test B that was sufficiently higher than the glass softening point caused the glass to flow and the airtightness to become insufficient. It is presumed that this caused the surface of the connection member to oxidize and the strength to decrease. This shows that it is preferable that the glass softening point of the sealing member of the electrode-embedded member used in high-temperature applications is higher than the temperature at which it is used.

[0076] In Example 6, a high thermal load was applied in Evaluation Test B, which is believed to have caused an opening in the glass due to the difference between the CTE of the glass and the CTE of the substrate, resulting in insufficient airtightness. It is presumed that this caused the surface of the connection member to oxidize, resulting in a decrease in strength. This shows that it is preferable for the difference between the CTE of the sealing member of the electrode-embedded member used in high-temperature applications and the CTE of the substrate to be as small as possible.

[0077] From the above, it was confirmed that the electrode-embedding member of the present invention can seal the terminal hole of the electrode-embedding member with the sealing member after the terminal is connected, and can reduce the risk of the glass shrinking during cooling and creating an opening through which oxygen can penetrate into the sealing member. It was also confirmed that, as a result, it is possible to prevent the surface of the connection member from oxidizing.

[0078] 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]

[0079] 100 Electrode embedding member 110 Base 112 Top surface 114 Bottom surface 120 electrodes 130 Connection member 140 Terminals 142 Terminal hole 144 Cushioning material 150 Sealing member 160 Shaft

Claims

1. An electrode embedding member, A base body formed in a flat plate shape by a ceramic sintered body; An electrode embedded in the substrate; a connection member electrically connected to the electrode and embedded in the base; A terminal hole provided in the base; a terminal electrically connected to the connection member and disposed in the terminal hole; a sealing member that seals the terminal hole, The sealing member is made of amorphous glass or crystallized glass having a glass softening point of 900°C or less and a CTE of 10 ppm or less, and is characterized in that it continuously covers from a portion of the side surface of the terminal to a portion of the side surface of the terminal hole.

2. a shaft formed in a cylindrical shape from a sintered ceramic body and joined to a lower surface of the base where the terminal hole is provided, 2. The electrode embedding member according to claim 1, wherein the sealing member continuously covers a portion of the side surface of the terminal hole, further via the lower surface, and a portion of the side surface on the inner diameter side of the shaft.

3. 3. The electrode-embedding member according to claim 1, wherein the glass softening point of the sealing member is 500[deg.] C. or higher.

4. The sealing member is made of ZnO or B ２ O ３ 4. The electrode-embedding member according to claim 3, comprising at least one component of the following:

5. The ZnO and B of the sealing member ２ O ３ 5. The electrode-embedding member according to claim 4, wherein the total content of the components is 70 wt % or less.

6. 3. The electrode-embedded member according to claim 1, wherein the sealing member has a CTE of 4.5 ppm or less.

7. 7. The electrode-embedding member according to claim 6, wherein an absolute value of the difference between the CTE of the sealing member and the CTE of the base is 1.5 ppm or less.

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