JP5974152B2 - Bonded body of ceramic member and metal member and manufacturing method thereof - Google Patents

Description

  The present invention relates to a joined body of a ceramic member and a metal member and a manufacturing method thereof.

  Conventionally, as a joined body of a ceramic member and a metal member, one in which an end portion of a metal member and a ceramic member are joined via a joint portion is known (Patent Document 1). In this bonded body, the bonding portion includes a metallized layer formed on the ceramic member, and a brazing bonding layer interposed between the metallized layer and the end of the metal member. Such a joined body is manufactured as follows. That is, first, a ring-shaped first brazing material containing Cu—Al—Si—Ti is placed on a joining surface of a disc-shaped ceramic member made of an AlN sintered body. Subsequently, the first brazing material is heated in a vacuum atmosphere at 1050 ° C. for 5 minutes to form a metallized layer. Subsequently, a ring-shaped second brazing material containing Ag—Cu is disposed on the metallized layer, an end surface of a cylindrical metal member is disposed thereon, and a weight is disposed on the metal member. This is heated in a vacuum atmosphere at 800 ° C. for 5 minutes to form a solder bonding layer. The joined body obtained in this way has almost no helium leak amount, and there is no crack and no helium leak amount even after thermal cycling.

JP 2000-219578 A

  However, such a bonded body has a problem that a sufficiently large tensile breaking load cannot be obtained because of a large residual stress.

  The present invention has been made to solve such a problem, and a main object of the present invention is to sufficiently increase the tensile breaking load of a joined body obtained by joining a ceramic member and a metal member.

  The joined body of the present invention employs the following means in order to achieve the main object described above.

The joined body of the present invention comprises:
A joined body obtained by joining a ceramic member and a metal member,
A metallized layer formed on the ceramic member and containing an active metal;
A brazing layer formed between the metallized layer and the metal member and having a melting point lower than that of the metallized layer;
Have
The flatness of the metallized layer is 22 μm or less.

According to this joined body, the tensile breaking load becomes sufficiently large. The reason is not clear, but it is presumed as follows. The metallized layer is formed with a thick central part and a thin outer peripheral part. The difference between the thickness of the central part and the thickness of the outer peripheral part is the flatness. When the wettability of the material constituting the metallized layer and the material forming the brazing layer is not sufficiently good, it is necessary to apply a load in order for the brazing material to spread over the entire surface of the metallized layer. When the flatness exceeds 22 μm, the distance between the outer peripheral portion of the metallized layer and the metal member is too far away, so that the load is difficult to be transmitted and the bonding strength of the brazing layer between the two is weakened. It is considered that the load is not large enough. On the other hand, if the flatness of the metallized layer is 22 μm or less, the load is also transmitted to the outer peripheral portion of the metallized layer, and the bonding force of the braze bonding layer between them is not weakened. Is considered to be large enough.

  In the joined body of the present invention, examples of the material of the ceramic member include an aluminum nitride sintered body, an alumina sintered body, and a zirconia sintered body. The ceramic member may be embedded with functional parts such as a resistance heating element, an electrostatic chuck electrode, and a plasma generating electrode.

  In the joined body of the present invention, for example, the metal member should be a member in which the surface of a core material having a thermal expansion coefficient close to that of a ceramic made of molybdenum, titanium, copper-tungsten composite or the like is coated with nickel, copper, gold, or the like. Of these, a member in which the surface of a molybdenum core is coated with nickel is preferable.

  In the joined body of the present invention, the metallized layer is formed using a brazing material for the metallized layer (hereinafter referred to as a first brazing material). As the first brazing material, for example, a silver brazing material, a copper brazing material, a nickel brazing material, a gold brazing material, a palladium brazing material, or the like may be used. Examples of the active metal include titanium, zirconium, hafnium, vanadium, niobium, and beryllium. In particular, when the material of the ceramic member is an alumina sintered body or an aluminum nitride sintered body, it is preferable to use titanium or zirconium as the active metal, and when the material of the ceramic member is a zirconia sintered body, the active metal As titanium, it is preferable to use titanium. Specific examples of the first brazing material include an Ag—Cu—Ti brazing material and an Ag—Cu—Ti—Sn brazing material. Since these first brazing materials are processed at 700 ° C. or higher, there is a possibility that a chemical reaction occurs at the interface between the ceramic member and the first brazing material to form a reaction layer. Such a reaction layer is considered to play a role of increasing the bonding strength between the ceramic member and the metallized layer.

  In the joined body of the present invention, the brazing layer is formed of a brazing material for the brazing layer (hereinafter referred to as a second brazing material). As the second brazing material, a brazing material having a melting point lower than that of the first brazing material is used, and examples thereof include a gold-based brazing material, an aluminum-based brazing material, and a zinc-based brazing material. When the second brazing material is melted, the melting temperature is set so that the metallized layer (first brazing material) does not melt. Specific examples of the second brazing material include, for example, an AuSn alloy (for example, Sn content of 15 to 37 wt%) and an AuGe alloy (for example, Ge content of 10 to 17 wt. %) And AuSi-based alloys (for example, the Si content is 3 to 4 wt%).

  According to the method of manufacturing the joined body of the present invention, a first brazing material is placed on a ceramic member, and the first brazing material is melted to form a metallized layer. Then, a first brazing material is formed between the metallized layer and the metal member. A ceramic that interposes two brazing materials and melts the second brazing material at a temperature lower than the melting point of the first brazing material, thereby forming the brazing bonding layer between the metallized layer and the metal member. A method of manufacturing a joined body in which a member and a metal member are joined, and the flatness of the metallized layer before the second brazing material is interposed between the metallized layer and the metal member is 22 μm or less (preferably 10 μm). Hereinafter, more preferably 5 μm or less.

  According to this method for manufacturing a joined body, the tensile fracture load of the obtained joined body becomes sufficiently large. The reason is as described above. The specific examples of the first brazing material and the second brazing material are also as described above.

In the manufacturing method of the joined body of the present invention, the thickness of the first brazing material when the first brazing material is installed on the ceramic member is preferably 20 to 30 μm. In this way, the flatness of the metallized layer when the metallized layer is generated by melting the first brazing material is 22 μm or less. For this reason, the work which improves flatness by grinding | polishing etc. becomes unnecessary. In addition, when the first brazing material is rolled to less than 20 μm, it becomes foil-like, making it difficult to handle, and the yield of metallization deteriorates.

1 is a schematic sectional view of a joined body 10. FIG. 6 is a manufacturing process diagram of the joined body 10.

  Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view of a joined body 10 of the present embodiment.

  The joined body 10 of the present embodiment is obtained by joining a ceramic member 12 and a metal member 14 at a joint portion 16. The ceramic member 12 is formed of an alumina sintered body. The metal member 14 has a nickel coating 14b formed on the bottom surface of a cylindrical molybdenum core material 14a. The joining portion 16 joins the bottom surface of the metal member 14 and the ceramic member 12. The joint portion 16 includes a metallized layer 16 a formed on the ceramic member 12, and a solder joint layer 16 b formed between the metallized layer 16 a and the nickel coating 14 b of the metal member 14. The metallized layer 16a is thicker at the center than at the outer periphery. When the difference between the thickness of the central portion of the metallized layer 16a and the thickness of the outer peripheral portion is defined as flatness, the flatness is 22 μm or less.

  Such a joined body 10 can be manufactured as follows, for example. FIG. 2 is a manufacturing process diagram of the joined body 10. First, a ceramic member 12 is prepared, and a first brazing material sheet 32 is placed on the surface of the ceramic member 12 (see FIG. 2A). As the first brazing material, an Ag brazing material containing Ti as an active metal (for example, Ag-Cu-Ti, Ag-Cu-Ti-Sn, Ag-Cu-Ti) or the like can be used. Then, the metallized layer 16a is formed on the ceramic member 12 by raising the temperature to the melting temperature of the first brazing material in a vacuum atmosphere in a heating furnace, keeping it for a predetermined time, and lowering the temperature (see FIG. 2B). ). At this time, there is a possibility that a chemical reaction occurs at the interface between the ceramic member 12 and the first brazing material and a reaction layer is formed. Such a reaction layer is considered to play a role of increasing the bonding strength between the ceramic member 12 and the metallized layer 16a. The metallized layer 16a has a thicker central portion than a peripheral portion due to surface tension when the sheet 32 is melted. At this time, if the flatness is 22 μm or less, the process proceeds to the next process as it is. If it exceeds 22 μm, the flatness is set to 22 μm or less by, for example, polishing before proceeding to the next process. Subsequently, the second brazing material sheet 34 is placed on the metallized layer 16a, and the metal member 14 is set so that the nickel coating 14b of the metal member 14 is in contact with the sheet 34 (see FIG. 2C). . As the second brazing material, a material having a melting point lower than that of the first brazing material (for example, Au—Sn, Au—Ge, Au—Si) or the like can be used. Then, a load is applied to the set metal member 14, the temperature is raised to the melting temperature (for example, 200 to 500 ° C.) of the second brazing material in a nitrogen atmosphere in a heating furnace, the temperature is kept for a predetermined time, and then the temperature is lowered (FIG. 2 ( d)). The melting temperature at this time is set to a temperature at which the second brazing material sheet 34 melts but the metallized layer 16a does not melt. By doing so, the brazing layer 16b is formed between the metallized layer 16a and the nickel coating 14b of the metal member 14, and the joined body 10 is completed.

According to the joined body 10 described above, the tensile breaking load becomes sufficiently large. The reason is not clear, but it is presumed as follows. Among the materials composing the metallized layer, Ti and AuG
e and poor wettability. Moreover, Ag and AuGe do not have good wettability. Therefore, it is necessary to apply a load in order for the AuGe brazing material to spread over the entire surface of the metallized layer. When the flatness of the metallized layer 16a exceeds 22 μm, the distance between the outer periphery of the metallized layer 16a and the metal member 14 is too far away, so that the load is not easily transmitted between them, and the bonding strength of the brazing layer 16b is weakened. As a result, it is considered that the tensile breaking load is not sufficiently large. On the other hand, if the flatness is 22 μm or less, since the distance between the outer peripheral portion of the metallized layer 16b and the metal member 14 is relatively short, the bonding force of the brazing bonding layer 16b between the two is not weakened. As a result, it is considered that the tensile breaking load has become sufficiently large.

  It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that the present invention can be implemented in various modes as long as it belongs to the technical scope of the present invention.

  For example, in the above-described embodiment, the surface of the ceramic member 12 (the surface on which the metal member 14 is attached) is a flat surface, but is not necessarily a flat surface. For example, the ceramic member 12 and the metal member 14 may be bonded via a bonding portion 16 in which a circular depression is provided in the ceramic member 12 and a metallized layer 16a and a brazing bonding layer 16b are laminated on the bottom surface of the depression. In this case, a ceramic member 12 having an electrode embedded therein is used, a terminal connected to the electrode is exposed on the bottom surface of the recess, and the ceramic member 12 and the metal are connected to the bottom surface of the recess via a joint portion 16. The member 14 may be joined. In this case, the metal member 14 is used for supplying power to the electrode. Examples of the electrode include a heater electrode (resistance heating element), an electrostatic chuck electrode, and a plasma generating electrode.

  In the embodiment described above, the ceramic member 12 is made of an alumina sintered body, but is not particularly limited to this, and may be, for example, an aluminum nitride sintered body or a zirconia sintered body. The active metal is preferably determined according to the material of the ceramic member 12. For example, in the case of an alumina sintered body or an aluminum nitride sintered body, titanium or zirconium is preferable, and in the case of a zirconia sintered body, Titanium is preferred.

  In the embodiment described above, the metal member 14 may be covered not only with the bottom surface of the molybdenum core material 14a but also with the nickel coating on the side surfaces and the surface. Further, the material of the core material is not limited to molybdenum, and may be, for example, titanium, a copper tungsten composite material, or the like. The material of the coating is not limited to nickel, but may be copper, gold or the like.

[Experimental Examples 1-5]
An alumina ceramic member provided with a recess having a diameter of 6 mm and a depth of 0.3 mm was prepared. One Ag-Cu-Ti sheet (manufactured by Tanaka Kikinzoku, TKC-711) cut out so as to have substantially the same shape as the bottom surface of the recess was set in the recess of the alumina ceramic member. The thicknesses of the sheets used in Experimental Examples 1 to 5 were 100 μm, 50 μm, and 25 μm, respectively. Then, the temperature was raised to 850 ° C. in a vacuum atmosphere in a heating furnace, kept for 10 minutes, and then lowered to form a metallized layer in the depression. The thickness of the central part and the outer peripheral part of the metallized layer were measured with an indicator (manufactured by mitutoyo, Digimatic Indicator). The measurement was performed without polishing the metallized layer. The difference between the thickness of the central portion and the thickness of the outer peripheral portion was defined as flatness, and the flatness was calculated. Table 1 shows the flatness of Experimental Examples 1 to 5.

Subsequently, an Au—Ge brazing material (made by Takanaka Tanaka, AuGe 12% plate (Au contains 12 to 13 wt% Ge) is formed in the dent in which the metallized layer is formed, so as to have substantially the same shape as the bottom surface of the dent. 1), and a metal terminal having a diameter of 5.95 mm and a height of 6 mm was set thereon. A metal terminal having a nickel coating on the surface of a molybdenum core was used. Then, a load was applied to the set metal terminal, and a nitrogen atmosphere was applied in the heating furnace.
The temperature was raised to 00 ° C., kept for 10 minutes, and then lowered to obtain a joined body in which the alumina ceramic member and the metal terminal were joined.

  The breaking load of the obtained joined body was measured using a tensile strength tester (manufactured by Shimadzu Corporation, Autograph). The results are shown in Table 1. When the flatness of the metallized layer was 65 μm and 36 μm as in Experimental Examples 1 and 2, only a low value was obtained for the tensile breaking load, but the flatness of the metallized layer was 22 μm as in Experimental Examples 3-5. , 20 μm, and 18 μm, sufficiently high values were obtained for the tensile breaking load.

[Experimental Examples 6 to 9]
An alumina ceramic member having no depression was prepared. On the surface of this alumina ceramic member, one sheet of Ag—Cu—Ti sheet (manufactured by Takanaka Tanaka, TKC-711) cut out to have the same shape as in Experimental Examples 1 to 5 was set. The thicknesses of the sheets used in Experimental Examples 6 to 9 were 100 μm, 50 μm, 25 μm, and 50 μm, respectively. Then, the temperature was raised to 850 ° C. in a vacuum atmosphere in a heating furnace, kept for 10 minutes, and then lowered to form a metallized layer. The flatness of this metallized layer was calculated in the same manner as in Experimental Examples 1-5. In Experimental Examples 6 to 8, the flatness was calculated without polishing the metallized layer, but in Experimental Example 9, the metallized layer was polished and the flatness was calculated after polishing. Table 2 shows the flatness of Experimental Examples 6 to 9.

  Subsequently, one Au—Ge brazing material (Tanaka Kikinzoku, AuGe 12% plate) cut out so as to have substantially the same shape as the metallized layer is set on the metallized layer, and Experimental Examples 1 to 5 are formed thereon. The same metal terminal was set. Then, a load is applied to the set metal terminal, the temperature is raised to 400 ° C. in a nitrogen atmosphere in a heating furnace, the temperature is kept for 10 minutes, and the temperature is lowered to obtain a joined body in which the alumina ceramic member and the metal terminal are joined. Obtained.

  The breaking load of the obtained joined body was measured in the same manner as in Experimental Examples 1-5. The results are shown in Table 2. When the flatness of the metallized layer was 63 μm and 32 μm as in Experimental Examples 6 and 7, the tensile breaking load was only low, but when the flatness was 17 μm as in Experimental Example 8, A sufficiently high value was obtained for the tensile rupture load. When the flatness was 3 μm as in Experimental Example 9, an extremely high value was obtained for the tensile rupture load.

[Experimental Examples 10 to 12]
An alumina ceramic member provided with a recess having a diameter of 6 mm and a depth of 0.3 mm was prepared. An Ag-Cu-Ti paste (manufactured by Fukuda Metals, ACT-2A) was thinly applied to the bottom surface of the depression of this alumina ceramic member using a brush or a cotton swab. After coating, the mixture was allowed to stand for about 30 minutes, then placed in a constant temperature bath at 120 ° C. and dried for 1 hour. The dried ceramic member was heated to 850 ° C. in a vacuum atmosphere in a heating furnace, kept for 10 minutes, and then cooled to form a metallized layer in the recess. The flatness of this metallized layer was calculated in the same manner as in Experimental Examples 1-5. Table 3 shows the flatness of Experimental Examples 10 to 12.

  Subsequently, an Au—Ge brazing material (Tanaka Kikinzoku, AuGe 12% plate) cut out so as to have the same shape as the bottom surface of the dent was set in the dent in which the metallized layer was formed. The metal terminal similar to ~ 5 was set. Then, a load is applied to the set metal terminal, the temperature is raised to 400 ° C. in a nitrogen atmosphere in a heating furnace, the temperature is kept for 10 minutes, and the temperature is lowered to obtain a joined body in which the alumina ceramic member and the metal terminal are joined. Obtained.

  The breaking load of the obtained joined body was measured in the same manner as in Experimental Examples 1-5. The results are shown in Table 3. When the flatness of the metallized layer was 14 to 15 μm as in Experimental Examples 10 to 12, a sufficiently high value for the tensile breaking load was obtained.

  From the results of the above Experimental Examples 1 to 12, it was found that when the flatness of the metallized layer is 22 μm or less, the tensile breaking load is a sufficiently high value of 35 kgf or more. Moreover, from the results of Experimental Examples 1 to 9, it was confirmed that the flatness of the metallized layer was improved as the original thickness of the sheet or paste used for the metallized layer was thinner (specifically, 20 to 30 μm). . Experimental examples 3 to 5, 8 to 12 correspond to examples of the present invention, and experimental examples 1, 2, 6, and 7 correspond to comparative examples of the present invention.

  The present invention can be used for, for example, an apparatus having a bonding portion between a ceramic member and a metal member such as an electrostatic chuck or a ceramic heater.

10 Bonded body, 12 Ceramic member, 14 Metal member, 14a Molybdenum core material, 1
4b Nickel coating, 16 joints, 16a metallized layer, 16b solder joint layer, 32, 34 sheets

Claims (9)

A joined body obtained by joining a ceramic member and a metal member,
A metallized layer formed on the ceramic member and containing an active metal;
A brazing layer formed between the metallized layer and the metal member and having a melting point lower than that of the metallized layer;
Have
The active metal is Ti;
The brazing layer is an AuGe brazing layer,
The flatness of the metallized layer is 22 μm or less.
Joined body.   The flatness of the metallized layer is 10 μm or less.
  The joined body according to claim 1.   The flatness of the metallized layer is 5 μm or less.
  The joined body according to claim 1 or 2.   The thickness of the outer peripheral portion of the metallized layer is greater than zero,
  The joined body according to any one of claims 1 to 3. A first brazing material is placed on the ceramic member, and the first brazing material is melted to form a metallized layer. Then, a second brazing material is interposed between the metallized layer and the metal member, and the first brazing material is disposed. Bonding between a ceramic member and a metal member, wherein the second brazing material is melted at a temperature lower than the melting point of the brazing material to form the brazing layer between the metallized layer and the metal member. The body manufacturing method,
The first brazing material contains Ti,
The second brazing material is AuGe brazing,
The flatness of the metallized layer before interposing the second brazing material between the metallized layer and the metal member is 22 μm or less.
Manufacturing method of the joined body.   The flatness of the metallized layer is 10 μm or less.
  The manufacturing method of the conjugate | zygote of Claim 5.   The flatness of the metallized layer is 5 μm or less.
  The manufacturing method of the conjugate | zygote of Claim 5 or 6.   The thickness of the outer peripheral portion of the metallized layer before interposing the second brazing material between the metallized layer and the metal member is greater than zero.
  The manufacturing method of the conjugate | zygote of any one of Claims 5-7. The thickness of the first brazing material when installing the first brazing material on the ceramic member is 20 to 30 μm.
The manufacturing method of the conjugate | zygote of any one of Claims 5-8 .

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