JP2001199775A - Joint structure to which metal is brazed and wafer support member using the same - Google Patents

Abstract

(57) Abstract: In a joint structure in which a metal containing Ni and a ceramic or another metal are brazed through a brazing material layer mainly composed of gold, diffusion of Ni into the brazing material layer is reduced. The present invention provides a bonded structure which is firmly bonded by preventing peeling of the brazing material layer and breakage of ceramics due to thermal stress by preventing the increase in hardness of the brazing material layer. Kind Code: A1 A bonding structure in which a platinum protective film is applied to at least a bonding surface of a metal containing Ni and a brazing material layer, and is brazed to ceramics or another metal using a brazing material layer mainly composed of gold. Form the body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joined structure obtained by brazing a metal, particularly a metal containing Ni or a metal coated with a Ni film, via a brazing material layer mainly composed of gold. Related to the wafer support member.

[0002]

2. Description of the Related Art
As the metal having heat resistance, Ni alone or an alloy containing Ni or a metal coated with a Ni film is used. And
In manufacturing a bonded structure by bonding these metals to other members, brazing is performed as a bonding means.

For example, in a ceramic heater which handles a large voltage and a large current, a poor connection at a connection portion between an electrode pad and a lead wire of the ceramic heater may cause a fire, and when water is involved, an electric shock may cause death. There is a risk of causing a related accident, and a ceramic heater joined with a brazing material has been used in order to improve the reliability of the joint.

As shown in FIG. 1, an example of a ceramic heater 10 includes a ceramic heater 1 in which a heating resistor 2 and an electrode extraction portion 3 are buried in a ceramic base 1, and a terminal of the electrode extraction portion 3 is a ceramic base. It is electrically connected to an electrode pad 4 formed on the outer peripheral surface of the material 1. Further, as shown in FIG. 5, a cross-sectional view in which the brazing portion of the lead wire 6 is enlarged, a Ni plating layer 7 is formed on the surface of the electrode pad 4.
Has been brazed by the brazing material layer 5.

Further, as another bonding structure in which a metal containing Ni or a metal on which a Ni film is deposited is brazed, there is a wafer support member used in a semiconductor manufacturing apparatus or the like.

As shown in FIG. 3 showing a state where the wafer support member is installed in a vacuum processing chamber, the wafer support member 21
The upper surface of the plate-shaped ceramic body 22 is used as a mounting surface 25 of the wafer, and a pair of internal electrodes for electrostatic attraction are arranged inside the mounting surface 25 in order from the mounting surface 25 side. 23 and internal electrode 2 for heating
4 are buried, and on the lower surface of the plate-shaped ceramic body 22, as shown in FIG.
Metal terminals 27, (26) electrically connected to 3)
They are joined via the brazing material layers 29 and (28). In addition,
Reference numeral 43 denotes a metallized layer formed on the plate-shaped ceramic body 22.

A gas introduction hole 30 penetrating the plate-like ceramic body 22 is provided at the center of the installation surface 25,
It has a groove 31 communicating with the gas introduction hole 30, and a metal pipe 32 is joined to the entrance side of the gas introduction hole 30 via a brazing material layer 33.

Further, the wafer support member 21 is hermetically installed in a vacuum processing chamber 39 via a metal ring 34, and the wafer support 21 and the ring 34
Are joined via a brazing material layer 35. In addition, 3
Reference numeral 6 denotes a plasma generating electrode provided above the wafer supporting member 21. The internal electrode 23 for electrostatic attraction provided on the wafer supporting member 21 is commonly used as the other plasma generating electrode.

Further, the metal terminals 26 and 27, the pipe 32 and the ring body 34 are heated to a high temperature in a state where they are exposed to the atmosphere due to the heat generated by the wafer support member 21, and therefore need to have heat resistance. -Was formed of a metal composed of a Ni alloy.

In order to perform various processes on the wafer W with the wafer support member 21, the wafer W is placed on the mounting surface 25 and a DC voltage is applied between the pair of internal electrodes 23, so that the wafer W An electrostatic attraction force such as a Coulomb force due to dielectric polarization and a Johnson-Rahbek force due to a small leakage current is developed between the inner electrode 23 and the mounting surface 2.
5 forcibly attracts and fixes the wafer W on
By supplying electricity to the internal electrode 24, the wafer W fixed to the installation surface 25 is heated, and He gas is supplied from the gas introduction hole 30 to the groove 31 between the wafer W and the installation surface 25 via the pipe 32. Thus, the temperature of the wafer W is equalized, and plasma is generated by applying high-frequency power between the pair of internal electrodes 23 and the plasma generating electrode 36. When a film forming gas is supplied into the vacuum processing chamber 39 in this state, a thin film can be formed on the wafer W.
If an etching gas is supplied into the vacuum processing chamber 39, a fine circuit pattern can be formed on the wafer W,
Further, if a cleaning gas is supplied into the vacuum processing chamber 39, components adhering to the surface of the wafer support member 21 and the surface of the vacuum processing chamber 39 can be removed.

As the brazing material layers 5, (28) and 29 used in the brazing portions in FIGS. 5 and 6, a brazing material mainly composed of silver has been conventionally used. Silver-based brazing materials are relatively inexpensive, and in the case of alloy brazing,
Since the brazing temperature can be lowered and the hardness of the brazing material is small, there is an advantage that thermal stress can be absorbed.

However, when a brazing material containing silver is used for the brazing material layers 5, (28) and 29, in the ceramic heater 10 shown in FIG. 1, a voltage is applied between the two lead wires 6 to repeatedly generate heat. Thus, there is a problem that silver in the brazing material layer 5 causes migration, and short-circuit occurs between the lead wires 6 so that heat is not generated.

In the wafer support member 21 shown in FIG. 3, when performing various processes such as film formation, etching, and cleaning, the wafer support member 21 is heated to 300 ° C. or more by the internal electrode 24 for heating, and is heated to such a high temperature. In order to generate an electrostatic attraction force or a plasma in a state where the
When the metal terminals 26 electrically connected to the metal terminal 26 are energized, silver ions in the brazing material layers 28, 29, 33, 35 joining the metal terminals 26, 27, the pipe 32, or the ring body 34 are converted to the plate-like ceramic body 22. Migration which moves on the surface of the pair of metal electrodes 2 of the pair of internal electrodes 23 occurs.
6, between the metal terminal 26 of the internal electrode 23 and the metal terminal 27 of the internal electrode 24, between each metal terminal 26 and the pipe 32, or between each metal terminal 26 and the ring 34, an electrostatic attraction force or plasma is generated. There have been problems in that it is not possible to generate the heat or to make the wafer support member 21 generate heat.

In addition, the internal electrodes 23 for electrostatic attraction are
In order to improve the releasability of the wafer W, a voltage having a polarity different from the voltage applied for suction is applied at the time of separation, or the polarity to be supplied to each wafer W is changed. At that time, migration of silver ions was accelerated, and the life was further shortened.

As a material that does not easily cause ion migration to solve such a problem, a brazing material mainly composed of gold is known. Since the brazing material mainly composed of gold has a high melting point and is easily melted and alloyed with other metals at the time of joining,
There is an advantage that the joining force of the brazing material layer portion can be increased.

However, when a brazing material mainly composed of gold is used as the brazing material layers 5, (28), 29 in FIGS. 5 and 6, the brazing material layers 5, 2 are alloyed with other metals.
Since the amount of metal that forms a solid solution in 8, 29 increases, and the hardness of the brazing material increases, there has been a problem that the increased hardness makes it impossible to absorb the thermal stress applied to the joint during brazing or heat generation.

That is, in FIGS. 5 and 6, the Ni plating layer 7,
Ni contained in the metal forming the lead wire 6 and the metal terminals 26 and 27 diffuses into the brazing material layer mainly composed of gold at the time of brazing, and the hardness of the brazing material layer increases. As a result, in FIG. 5, cracks occur in the ceramic base material 1 around the brazing material layer 5 and the brazing material layer 5 is peeled off. There are problems that cracks occur in the plate-like ceramic body 22 around the portions 29 and (28), and the brazing material layers 29 and (28) peel off.

In the wafer support member 21 shown in FIG. 3, the same problem occurs when the brazing material mainly composed of gold is used for the brazing material layer 33 of the gas introduction hole 30 and the brazing material layer 35 of the pipe 34. Had occurred.

[0019]

Means for Solving the Problems Accordingly, the present inventor has proposed:
In view of the above problems, various studies have been conducted to prevent Ni adhered to or contained in metals such as plating layers, lead wires, metal terminals, pipes, and ring bodies from diffusing into a brazing material layer mainly composed of gold. As a result, they found that if a platinum protective film was applied to the metal to be brazed, the diffusion of Ni into the brazing material layer could be prevented, and the present invention was reached.

That is, the present invention provides a method for producing a metal containing Ni or N
In a bonded structure in which a metal having an i-film is brazed through a brazing material layer, a brazing material containing gold as a main component is used for the brazing material layer, and the Vickers hardness ( _HV0.1 ) is determined. 150 or less, and a protective layer of platinum is applied to at least a bonding surface of the metal with the brazing material layer.

Further, according to the present invention, the upper surface of the plate-shaped ceramic body is used as a mounting surface of a wafer, and at least one internal electrode is provided therein. A metal terminal containing Ni or a metal terminal coated with a Ni film that is electrically connected to a metal terminal via a brazing material layer, wherein the brazing material layer contains gold as a main component. The brazing material is used and its Vickers hardness ( _{HV 0.1} ) is 150
The present invention is further characterized in that a platinum protective film is applied to at least a bonding surface of the metal terminal with the brazing material layer.

Further, the present invention is characterized in that the thickness of the platinum protective film is 0.5 to 100 μm.

[0023]

Embodiments of the present invention will be described below.

FIG. 1 is a partially cutaway perspective view showing a ceramic heater which is an example of a joint structure to which a metal is brazed.

The ceramic heater 10 includes an electrode pad 4 having a heating resistor 2 and an electrode extraction portion 3 embedded in a ceramic substrate 1, and an end of the electrode extraction portion 3 formed on the outer peripheral surface of the ceramic substrate 1. It is electrically connected to
Further, as shown in FIG. 2 which is an enlarged sectional view of a brazing portion of the lead wire 6 according to the present invention, a platinum protective film 11 is applied on the surface of the electrode pad 4, and the platinum protective film 12 is A lead wire 6 made of Ni is brazed through a brazing material layer 5 made of a brazing material mainly composed of gold having a Vickers hardness (H _V0.1 ) of 150 or less. Then, a current is applied between the two lead wires 6 to cause the heat generating resistor 2 to generate heat, so that the tip of the ceramic heater 10 generates heat.

FIG. 3 is a cross-sectional view showing a state in which a wafer support member, which is another example of the joint structure to which metal is brazed, is installed in a vacuum processing chamber.

The wafer support member 21 is composed of a disk-shaped plate-shaped ceramic body 22.
Is a wafer mounting surface 25, and a pair of internal electrodes 23 for electrostatic attraction and an internal electrode 24 for heating are respectively buried inside the mounting surface 25 in order from the mounting surface 25 side. As shown in FIG. 4, Fe-Co having a metallized layer 43 on the inner wall surface of the concave portion 41 opened on the lower surface of the plate-shaped ceramic body 22 and having a protective film 42 of platinum adhered thereto.
A metal terminal 27, (26) made of a -Ni alloy is inserted into the recess 41, and a brazing material layer 29, (2) made of a brazing material mainly composed of gold having a Vickers hardness ( _{HV 0.1} ) of 150 or less.
8), each internal electrode 2
The metal terminals 3 and 24 are electrically connected to the metal terminals 26 and 27, respectively.

A gas introduction hole 30 penetrating through the plate-like ceramic body 22 is provided at the center of the installation surface 25.
A metal pipe 32 made of an Fe-Co-Ni alloy and having a protective film (not shown) made of platinum and having a groove 31 communicating with the gas introduction hole 30 and having an entrance side of the gas introduction hole 30.
_Are bonded via a brazing material layer 33 made of a brazing material mainly composed of gold having a Vickers hardness (H _V0.1 ) of 150 or less.

Further, the wafer support member 21 is hermetically installed in a vacuum processing chamber 39 via a metal ring 34 made of an Fe-Co-Ni alloy on which a platinum protective film (not shown) is applied. The wafer support member 21 and the ring body 34 are joined via a brazing material layer 35 made of a brazing material mainly composed of gold having a Vickers hardness (H _V0.1 ) of 150 or less.

Reference numeral 36 denotes a plasma generating electrode provided above the wafer supporting member 21. The internal electrode 23 for electrostatic attraction provided on the wafer supporting member 21 is commonly used as the other plasma generating electrode. It has become.

In order to perform various processes on the wafer W with the wafer support member 21, the wafer W is placed on the installation surface 25, and a DC voltage is applied between the pair of internal electrodes 23, so that the wafer W An electrostatic attraction force such as a Coulomb force due to dielectric polarization and a Johnson-Rahbek force due to a small leakage current is developed between the inner electrode 23 and the mounting surface 2.
5 forcibly attracts and fixes the wafer W on
By supplying electricity to the internal electrode 24, the wafer W fixed to the installation surface 25 is heated, and He gas is supplied from the gas introduction hole 30 to the groove 31 between the wafer W and the installation surface 25 via the pipe 32. Thus, the temperature of the wafer W is uniformed, and plasma is generated by applying high-frequency power between the pair of internal electrodes 23 and the plasma generating electrode 36. When a film forming gas is supplied into the vacuum processing chamber 39 in this state, a thin film can be formed on the wafer W, and when an etching gas is supplied into the vacuum processing chamber 39, A fine circuit pattern can be formed, and if a cleaning gas is supplied into the vacuum processing chamber 39, components adhering to the wafer support member 21 and the surface of the vacuum processing chamber 39 can be removed.

The feature of the present invention is that, as shown in FIGS. 2 and 4, a brazing material containing gold as a main component is used as the brazing material, and the Vickers hardness ( _{HV 0.1} ) of the brazing material is 15 _%.
0 or less, and a protective film 1 of platinum is formed on the surface of a lead wire 6 or an electrode pad 4 which is in contact with the brazing material, or a metal surface containing Ni such as metal terminals 26 and 27, a pipe 32 and a ring body 34.
1, 12, and 42 are attached.

That is, the hardness of the brazing material layers 5, (28), 29 made of a brazing material mainly composed of gold is determined as Vickers hardness (H
_V0.1 ), the Vickers hardness (H
_{If v0.1} ) exceeds 150, the thermal stress generated at the time of brazing and the thermal stress applied by repetition of heat generation cannot be absorbed by the brazing material layers 5, (28) and 29, so that the brazing material layers 5 and ( 28), 29, ceramic bases 1 around
22 and cracks in the brazing material layers 5, (28),
This is because peeling occurs at the bonding interface with the substrate 29.

Further, the brazing material mainly composed of gold easily reacts with a component in the contacting metal to form an alloy, and the hardness of the brazing material becomes high. It is difficult to react with the metal or the brazing material layers 5, (28), 29 forming the metal terminals 26, 27, etc., has a melting point higher than the brazing temperature, and has a metal component mainly composed of gold. After extensive research on protective films 11, 12, and 42 that can prevent diffusion to 5, (28), and 29,
It has been found that platinum is most effective, and by forming protective films 11, 12, and 42 of platinum on at least the bonding surfaces in contact with the brazing material layers 5, (28) and 29, the Ni content in the metal is reduced.
Can be prevented from diffusing into the brazing material layers 5, (28), 29, and the hardness of the brazing material layers 5, (28), 29 can be prevented from increasing. Even if thermal stress acts, the brazing material layers 5, (28), 2
It is possible to effectively prevent cracks from being generated in the ceramic bases 1 and 22 around the periphery of the brazing material 9 and peeling of the brazing material layers 5, (28) and 29.

By the way, Vickers hardness ( _{HV 0.1} ) 15
The brazing material mainly composed of gold forming the brazing material layers 5, (28), 29 having a thickness of 0 or less is an alloy brazing of gold (90% by weight or more) -nickel (10% by weight or less) or gold (50% by weight). Above) -Copper (50% by weight or less) alloy brazing or alloy brazing containing vanadium or molybdenum (4% by weight or less) in these alloys can be used.

In order to achieve the above-described effects, the thickness t of the protective films 11, 12, 42 should be set to 0.5 to 100.
It is preferably set to μm. When the thickness t is smaller than 0.5 μm, defects are easily generated in the protective layers 11, 12, and 42 of platinum, and Ni contained in the metal forming the lead wire 6, the electrode pad 4, the metal terminals 26, 27 and the like is low. Material layer 5, (2
8), the effect of preventing diffusion to 29 is small. Conversely, if the thickness t exceeds 100 μm, cracks occur in the platinum protective layers 11, 12, and 42 due to the difference in thermal expansion with the brazing material, and if the thickness becomes severe, This is because the protective films 11, 12, and 42 are peeled off.

It is to be noted that the protective films 11, 12, and 42
Means for coating with a thickness of 100 μm include a plating method,
A well-known film forming means such as a sputtering method, a thermal spraying method, and a coating method may be used.

By the way, in the present embodiment, only the joint between the metal terminals 27 and (26) in the wafer support member 21 shown in FIG. 3 has been described, but the brazing material layer 33 of the gas introduction hole 30 and the brazing of the pipe 34 are described. Even when a brazing material mainly composed of gold is used for the material layer 35, the brazing material layers 33 and 35 may be used.
According to the present invention, if a Vickers hardness (H _V0.1 ) of 150 or less is used and a protective film of platinum is applied to at least the joint surfaces of the pipe 32 and the ring body 34 with the brazing material layers 33 and 35, Similar effects can be obtained.

The material for forming the ceramic base 1 forming the ceramic heater 10 shown in FIG. 1 and the plate-shaped ceramic body 21 forming the wafer support member 21 shown in FIG. 3 is not particularly limited. And ceramics containing alumina, silicon carbide, silicon nitride or the like as a main component.

Further, it is needless to say that the present invention is not limited to the embodiment described above, but can be improved and changed without departing from the gist of the present invention.

[0041]

EXAMPLE First, a ceramic base material containing aluminum nitride, alumina and silicon nitride as main components was prepared.

The ceramic substrate containing aluminum nitride as a main component is composed of 6% by weight of Er ₂ O ₃ and 0.5% by weight of CaO as a sintering aid with respect to a high-purity aluminum nitride powder.
The slurry prepared by adding the solvent and the binder was granulated by spray drying to prepare granules. Then, the obtained granules were filled in a mold, and a 5 mm × 5 mm × 45 mm molded body was formed under a pressing pressure of 98 MPa, and then a tungsten paste was printed on the surface of the molded body.
By firing in a nitrogen atmosphere at 00 ° C., a ceramic substrate made of aluminum nitride coated with tungsten was manufactured.

The ceramic substrate containing alumina as a main component is prepared by adding CaO as a sintering aid to alumina powder.
5% by weight, 3.5% by weight of MgO, ₂ % by weight of SiO ₂
Using the raw materials mixed in the range described above, a slurry prepared by adding a solvent and a binder was granulated by spray drying to produce granules. Then, the obtained granules were filled in a mold and pressed at 98 MPa with a pressure of 5 mm × 5 mm × 45 m.
After forming a molded body of m, a paste of tungsten was printed on the surface thereof and fired in a H ₂ -N ₂ mixed gas at 1600 ° C. to prepare a ceramic base material made of alumina coated with tungsten. .

The ceramic base material mainly composed of silicon nitride, sintered to silicon nitride powder, the Y ₂ O ₃ 5 wt% as a sintering aid, an Al ₂ O ₃ 0.5 wt%, a SiO ₂ After conclusion 2
Using the raw materials mixed so as to have a weight%, a slurry prepared by adding a solvent and a binder was granulated by spray drying to prepare granules. Then, the obtained granules are filled in a mold, and pressed at a pressure of 98 MPa to 5 mm × 5 m.
After forming a molded body of mx 45 mm, a paste of tungsten carbide is printed on the surface thereof,
By firing under pressure in a nitrogen atmosphere at 0 atm, a ceramic substrate made of silicon nitride was produced.

Next, a protective film made of platinum having a thickness of 2.0 μm was formed on the tungsten and tungsten carbide formed on the surface of each ceramic substrate by electroless plating.

On the other hand, a lead wire made of Ni having a diameter of 0.6 μm is prepared, and a protective film made of platinum having a thickness of 0.3 to 2 μm is applied on the surface thereof by electroless plating. A paste coated with a protective film made of platinum and having a thickness of 5 to 120 μm was prepared by applying a paste and baking the paste at 1000 ° C.

Then, each lead wire and the tungsten film were brazed using the following brazing materials.

The brazing material has a weight ratio of gold: copper of 50:50,
The weight ratio of gold: copper is 90:10, and the weight ratio of gold: copper is 95:
As a comparative example, a tungsten film and a lead wire in which a platinum protective film was not applied were also prepared, and were brazed using the above-mentioned brazing material.

Then, the Vickers hardness of the brazing material layer before and after the brazing process was measured, and the presence or absence of cracks in the protective film made of platinum was visually checked. Regarding the measurement of Vickers hardness, the sample was cut in the direction of cutting the lead wire into a slice, the surface of the brazing material was mirror-polished, and the Vickers hardness when pressed with a load of 100 g using an indenter was determined. Further, a cycle of heating from room temperature to 400 ° C. for 5 minutes and forcibly air-cooling for 5 minutes was repeated 2000 times, and the tensile strength of the lead wire before and after the heat cycle was measured.

The results are as shown in Table 1.

[0051]

[Table 1]

As a result, No. 1 having no platinum protective film was obtained. 1,
In _Nos. 5 and 16, the Vickers hardness (H _V0.1 ) of the brazing material layer after brazing exceeded 150, and the tensile strength after the heat cycle test was reduced to 30 N or less. For these samples, the components of the brazing material layer were confirmed by an EPMA analyzer of an electron microscope, and it was found that nickel forming the lead wire was dispersed.

Further, even when the protective film made of platinum is applied to the tungsten film and the lead wire, the protective film made of platinum has a thickness of 0.3 μm. In No. 6, the tensile strength was reduced by half compared to the initial stage. With respect to this sample, the distribution of nickel in the brazing material layer was confirmed by an EPMA analyzer of an electron microscope.
When nickel was dispersed and the cross section of the platinum protective layer was confirmed by an electron micrograph, it was found that there were holes in some parts of the protective film, and that the nickel of the lead wire had diffused from those parts.

Further, in the case of No. 3 in which the thickness of the platinum protective film was 120 μm. In No. 15, cracks occurred in the platinum protective layer when the platinum protective layer was baked.

On the other hand, a platinum protective film is applied to the tungsten film and the lead wire, so that the platinum protective film is 0.1.
No. 5 formed in the range of 5 to 100 μm. 2-4, 7-1
Nos. 4, 17 to 21 have no cracks in the protective film made of platinum, have no diffusion of nickel forming a lead wire into the brazing material layer, and have no increase in hardness, so that the durability of the brazed portion is improved. Could be better.

[0056]

As described above, according to the present invention, in a joined structure in which a metal containing Ni or a metal coated with a Ni film is brazed via a brazing material layer, the brazing material layer has A Vickers hardness (H _V0.1 ) of 150 or less and a platinum protective layer adhered to at least a bonding surface of the metal with the brazing material layer. Since it is possible to prevent Ni from diffusing into the material layer and increase in hardness, even if a thermal stress is applied, it can be absorbed by the brazing material layer. For this reason, the deterioration of the metal can be suppressed, the peeling of the brazing material layer can be prevented, and the brazing can be surely performed.

Further, according to the present invention, the upper surface of the plate-shaped ceramic body is used as a mounting surface of the wafer, and at least one internal electrode is provided therein. In a wafer support member in which metal terminals electrically connected to electrodes are joined via a brazing material layer, a brazing material containing gold as a main component is used for the brazing material layer, and its Vickers hardness (H _V0.1 )
Is not more than 150, and a protective film of platinum is applied to at least the bonding surface of the metal terminal with the brazing material layer.
Even if a metal coated with a film is used, it is possible to prevent Ni from diffusing into the brazing material layer and increase in hardness, so that even if thermal stress is applied, it is absorbed by the brazing material layer, and the plate-like ceramic is absorbed. Strong bonding can be achieved without breaking the body or deteriorating the metal terminals.

[Brief description of the drawings]

FIG. 1 is a partially broken perspective view showing a ceramic heater which is an example of a joining structure to which a metal is brazed.

FIG. 2 is an enlarged sectional view showing a brazed portion between an electrode pad of the present invention and a lead wire in the ceramic heater shown in FIG. 1;

FIG. 3 is a cross-sectional view showing a state in which a wafer support member, which is another example of a bonding structure to which metal is brazed, is installed in a vacuum processing chamber.

4 is an enlarged cross-sectional view showing a brazed portion between a plate-shaped ceramic body of the present invention and a metal terminal in the wafer support member shown in FIG. 3;

FIG. 5 is an enlarged cross-sectional view showing a brazed portion between a conventional electrode pad and a lead wire in the ceramic heater shown in FIG.

6 is an enlarged cross-sectional view showing a brazed portion between a conventional plate-shaped ceramic body and a metal terminal in the wafer support member shown in FIG.

[Explanation of symbols]

 1: Ceramic base material 2: Heating resistor 3: Electrode take-out part 4: Electrode pad 5: Brazing material layer 6: Lead wire 11, 12: Platinum protective film 21: Wafer support member 22: Plate-like ceramic body 23: Static Internal electrode for electroadsorption 24: Internal electrode for heating 25: Installation surface 26, 27: Metal terminal 28, 29: Brazing material layer 30: Gas introduction hole 31: Groove 32: Pipe 33: Brazing material layer 34: Ring body 35: brazing material layer

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) H05B 3/03 H05B 3/03 // B23K 35/30 310 B23K 35/30 310A

Claims (4)

[Claims] In a joint structure in which a metal is brazed through a brazing material layer, the brazing material layer is made of a brazing material mainly composed of gold, and has a Vickers hardness (H _V0.1 ) of 150.
A bonding structure in which a metal is brazed, wherein a platinum protective film is adhered to at least a bonding surface of the metal with the brazing material layer. 2. An upper surface of a plate-shaped ceramic body is a mounting surface of a wafer, and at least one internal electrode is provided therein, and at least a surface of the plate-shaped ceramic body other than the mounting surface is electrically connected to the internal electrodes. In a wafer supporting member in which metal terminals to be connected are joined via a brazing material layer, the brazing material layer is made of a brazing material mainly composed of gold and has a Vickers hardness (H _V0.1 ) of 150. A wafer support member, wherein a platinum protective film is adhered to at least a bonding surface of the metal terminal with the brazing material layer. 3. The protective film of platinum has a thickness of 0.5 to 100.
The joint structure for a metal member according to claim 1, wherein the thickness is μm. 4. The thickness of the platinum protective film is 0.5 to 100.
3. The wafer support member according to claim 2, wherein the thickness is μm.