JP2000191380A - Joined body of ceramic member and metallic member, and wafer supplying member using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wafer supporting member which is free from gas leakage in the joined part between a planar ceramic body 1 forming the wafer supporting member and a cylindrical metallic body 3 in spit of application of repetitive heat cycles thereto at the time of brazing at >=900 deg.C or in a high temperature region from ordinary temperature to >=650 deg.C and has excellent durability. SOLUTION: The rear surface of the planar ceramic body 1 having a wafer loading surface 1a is provided with annular recessed parts 1b, and annular engaging parts 4 of an approximately U shape in the cross-sectional shape disposed on one end side of the cylindrical metallic body 3 are inserted into these recessed parts 1b. The engaging parts 4 are internally provided with stress relief rings 6 of <=2×106/ deg.C in the difference in thermal expansion from the planar ceramic body 1. The wafer supporting member is constituted by joining the planar ceramic body 1, the cylindrical metallic body 3 and the stress relief rings 6 respectively by brazing filler metals.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joined body formed by joining a ceramic member and a metal member with a joining layer made of a brazing material, and a wafer supporting member using the same. In particular, PVD, C
It is suitable for a semiconductor manufacturing apparatus for performing a film forming process such as VD or sputtering or an etching process.

[0002]

2. Description of the Related Art Conventionally, in order to obtain a joined body in which a ceramic member and a metal member are joined, both members are joined with a joining layer made of a brazing material.

For example, in a semiconductor device manufacturing process,
2. Description of the Related Art Semiconductor manufacturing apparatuses such as a film forming apparatus such as PVD, CVD, and sputtering for forming a thin film on a semiconductor wafer (hereinafter, referred to as a wafer) and a dry etching apparatus for performing fine processing on a semiconductor wafer are subjected to vacuum processing. A wafer support member called a susceptor or an electrostatic chuck is used to hold the wafer in a room. The wafer support member is provided on the upper surface of a plate-shaped ceramic body 11 as shown in FIG.
0 on which the internal electrode 12 is provided, and on the lower surface of the plate-shaped ceramic body 11, a flange 13a of the cylindrical metal body 13 is joined to a bonding layer 14 made of brazing material. Some were airtightly bonded.

In this wafer support member, a flange portion 13b provided at a lower end of the cylindrical metal body 13 is air-tightly joined to a bottom surface of a vacuum processing chamber 18 via an O-ring 17, and a lower surface of the plate-like ceramic body 11 is provided. A lead wire connected to a current-carrying terminal 21 to the internal electrode 12 provided in the device, a temperature detecting element 22 such as a thermocouple, or a temperature detecting element 23 of a wafer 30 such as a temperature measuring optical fiber is led out from the inside of the cylindrical metal body 13 to the outside. Was supposed to. In order to use this wafer support member, when the wafer 30 is mounted on the mounting surface 11a, the inside of the vacuum processing chamber 18 is evacuated, and when the internal electrode 12 is used for electrostatic attraction, By applying a DC voltage between the wafer 30 and the internal electrode 12 to develop an electrostatic attraction force, the wafer 30 on the mounting surface 11a is attracted and fixed to perform various processes. When used as a heater electrode, various processes are performed by applying an AC voltage to the internal electrode 12 while heating the wafer 30 on the mounting surface 11a.

At this time, since the upper and lower ends of the tubular metal body 13 are air-tightly joined, the inside of the tubular metal body 13 can be shielded from the atmosphere in the vacuum processing chamber 18. That is, the inside of the vacuum processing chamber 18 is 10 ^-9 torr / sec.
Under the following high vacuum and high temperature with corrosive gas introduced, the inside of the tubular metal body 13 can be an atmospheric atmosphere communicating with the outside.

Therefore, it is possible to prevent the temperature detecting elements 22 and 23, the current-carrying terminals 21 and the conductors connected thereto from being exposed to corrosive gas.

In recent years, ceramics such as alumina and aluminum nitride have been used as the material of such a plate-shaped ceramic body 11, while the cylindrical metal body 13 is formed of metal, and the thermal expansion of both members In order to reduce the stress caused by the difference, the thickness of the flange portion 13a of the cylindrical metal body 13 is reduced to about 0.1 to 2 mm, and the plate-shaped ceramic body 11 and the cylindrical metal body 13 are joined. Ag-based brazing materials have been used as brazing materials.

[0008]

By the way, in the above-mentioned semiconductor manufacturing apparatus, 100-300 ° C., and even 600 ° C.
In many cases, the wafer 30 is processed under a high temperature condition of about ℃.
The wafer support member is subjected to a thermal cycle between room temperature and the processing temperature.

As a result, the thermal stress due to this thermal cycle is concentrated on the joining layer 14 between the tubular metal body 13 and the plate-shaped ceramic body 11 and is repeatedly generated.
As shown in (b), the flange portion 13a of the cylindrical metal body 13
However, there is a problem in that a creep deformation causes a gap to be formed between the plate-shaped ceramic body 11 and the flange portion 13 a to be separated from the plate-shaped ceramic body 11. That is, when the tubular metal body 13 having a large thermal expansion coefficient and the plate-shaped ceramic plate 11 having a small thermal expansion coefficient, which have been joined in a normal shape during heating, are cooled, the tubular metal body 13 is separated from the plate-shaped ceramic body 11. As the shrinkage proceeds, a tensile stress acts between the tubular metal body 13 and the plate-shaped ceramic body 11, and when this state progresses, peeling or cracking occurs from the bonding layer 14.

This problem occurs in the use of several to several tens of cycles in the wafer support member shown in FIG. 3, and when a high vacuum state is required as in a semiconductor manufacturing apparatus, the wafer support member is constituted. Plate-shaped ceramic body 11
Gas leaks from the space between the metal body 13 and the cylindrical metal body 13, the high vacuum state cannot be maintained, and when the gas leak occurs, the corrosive gas in the vacuum processing chamber 18 is removed by the cylindrical metal body 1.
3, there is a problem that the temperature detecting elements 22 and 23, the energizing terminal 21, and the conductor are corroded.

Therefore, as shown in FIG. 5, the applicant of the present invention provided a wafer support member for solving the above-mentioned problems, in which the thermal expansion difference between the plate-shaped ceramic body 11 and the lower surface of the flange portion 13a of the cylindrical metal body 13 was formed. A wafer support member in which a stress relaxation ring 24 having a small diameter is joined with a brazing material has been previously proposed (see Japanese Patent Application Laid-Open No. 9-21375).

In this wafer support member 11, the flange portion 13a of the cylindrical metal body 13 is sandwiched between the plate-like ceramic body 11 having a similar thermal expansion coefficient and the stress relaxation ring 24 to restrain the deformation of the flange portion 13a. The flange portion 13 of the plate-shaped ceramic body 11 and the cylindrical metal body 13
There is an advantage that it is possible to effectively prevent a gap from being formed between a and a.

However, in recent years, the processing temperature has been further increased with the increase in the film material formed on the wafer 30,
It is desired to process the wafer 30 under a high temperature condition of 650 ° C. or higher. However, since the processing temperature of the Ag-based brazing material is close to the melting point of the brazing material, it can sufficiently withstand the repeated thermal stress. However, when the processing temperature exceeds 650 ° C. or more, oxygen is remarkably easily passed, and airtightness cannot be maintained.

Therefore, under such high temperature treatment conditions,
As the brazing material, an Au-Ni or NiCr-based brazing material having a high melting point may be used, but the brazing temperature of these brazing materials is as high as 900 ° C. or more, and even in the structure shown in FIG. Since the thermal expansion difference between the plate-shaped ceramic body 11 and the tubular metal body 13 cannot be sufficiently absorbed,
As shown in FIGS. 4A and 4B, the flange portion 13a of the cylindrical metal body 13 is creep-deformed to form a gap between the flange 13a and the plate-shaped ceramic body 11, or the flange 13 is separated from the plate-shaped ceramic body 11. Peeling could not be avoided.

[0015]

SUMMARY OF THE INVENTION In view of the above-mentioned problems, the present invention inserts an engaging portion having a substantially U-shaped cross section provided on a metal member into a concave portion of a ceramic member. A stress relaxation member having a thermal expansion difference of not more than 2 × 10 ⁻⁶ / ° C. from the ceramic member is disposed in the joint portion, and the ceramic member, the metal member, and the stress relaxation member are joined by a brazing material. It constitutes a joined body of a ceramic member and a metal member.

Further, according to the present invention, the upper surface of the plate-like ceramic body is used as a wafer mounting surface, and an annular concave portion is provided on the lower surface thereof.
An annular engaging portion having a substantially U-shaped cross section provided on one end side of the cylindrical metal body is inserted into the concave portion, and the thermal expansion difference between the plate-shaped ceramic body and the engaging portion is within the engaging portion. 2x1
A wafer support member is formed by disposing a stress relaxation ring having a temperature of 0 ⁻⁶ / ° C. or less, and joining the plate-shaped ceramic body, the cylindrical metal body, and the stress relaxation ring with a brazing material. is there.

[0017]

Embodiments of the present invention will be described below.

FIG. 1 is a cross-sectional view showing an example in which a joined body of a ceramic member and a metal member of the present invention is applied to a wafer supporting member for holding a semiconductor wafer. The same parts as those in the conventional example are denoted by the same reference numerals.

The wafer supporting member shown in FIG. 1 has a mounting surface 1a on which a semiconductor wafer 30 is mounted on the upper surface of the plate-shaped ceramic body 1.
The internal electrode 2 is buried therein, and is called a susceptor. In addition, the plate-shaped ceramic body 1
Has an annular concave portion 1b on the lower surface thereof. In this concave portion 1b,
An annular engaging portion 4 having a substantially U-shaped cross section provided on one end side of the cylindrical metal body 3 is inserted.
The difference in thermal expansion from the plate-like ceramic body 1 is 2 × 10 ^−6.
/ ° C or less is inserted, and the plate-shaped ceramic body 1, the cylindrical metal body 3, and the stress relaxation ring 6 are inserted.
Are hermetically joined with Au or NiCr brazing material.

The flange portion 5 provided at the lower end of the cylindrical metal body 3 is hermetically joined to the bottom surface of the vacuum processing chamber 18 via an O-ring 17 so that the wafer support member is installed in the vacuum processing chamber 18. is there.

On the lower surface of the plate-shaped ceramic body 1, a temperature detecting element 22 of the plate-shaped ceramic body 1 such as an electric connection terminal 21 to the internal electrode 2 or a thermocouple or a temperature detecting element of a wafer 30 such as an optical fiber for temperature measurement. 23 are provided, and lead wires connected thereto are led out from the inside of the tubular metal body 3 to the outside.

To use this wafer support member, the wafer 30 is mounted on the mounting surface 1a, and the vacuum processing chamber 18 is used.
In the case where the inside of the device is vacuum and the internal electrode 2 is used for electrostatic attraction, a DC voltage is applied between the wafer 30 and the internal electrode 2 to develop an electrostatic attraction force, so that the mounting surface 1 a When the internal electrode 2 is used as a heater electrode, an AC voltage is applied to the internal electrode 2 to heat the wafer 30 on the mounting surface 1a. While performing various processing.

According to the present invention, an annular concave portion 1b is provided on the lower surface of the plate-shaped ceramic body 1, and a cross-sectional shape provided at one end side of the cylindrical metal body 3 is substantially U-shaped in the concave portion 1b. While inserting the annular engaging portion 4
A stress relaxation ring 6 having a thermal expansion difference similar to that of the plate-shaped ceramic body 1 is inserted into the engaging portion 4 so that each member is brought into contact with an Au-based or NiCr-based brazing material having a high melting point. Therefore, even when brazing is performed at a high temperature of 900 ° C. or more, or when a thermal cycle is repeatedly performed in a processing temperature range from normal temperature to 650 ° C. or more, the engagement between the concave portion 1 b of the plate-shaped ceramic body 1 and the cylindrical metal body 3. It is possible to effectively prevent a gap from being formed with the portion 4.

That is, as shown in an enlarged view of the joint portion in FIG. 2, the stress relaxation ring 6 is joined to the bottom surface of the concave portion 1b of the plate-like ceramic body 1 by a brazing material, and the concave portion 1b of the plate-like ceramic body 1 is formed. The flange 4a of the engaging portion 4 provided on the cylindrical metal body 3 is inserted into the gap between the metal plate 3 and the stress relaxation ring 6, and is joined by a brazing material. Even if thermal stress is generated between the flange 4a of the body 3 and the flange 4a of the cylindrical metal body 3, the flange 4a of the tubular metal body 3 is clamped and restrained by a stress relaxation ring 6 having a similar thermal expansion coefficient to that of the plate-shaped ceramic body 1. Therefore, the deformation of the flange 4a of the tubular metal body 3 can be prevented.

Further, the engaging portion 4 of the cylindrical metal body 3 has a substantially U-shaped cross section, and the area occupied in the horizontal direction in the drawing can be reduced, so that the thermal stress acting in the horizontal direction can be reduced. In addition, since the engagement portion 4 is provided with the flange 4a to increase the surface area, the joining strength between the plate-shaped ceramic body 1 and the tubular metal body 3 can be greatly increased.

Thus, when the wafer support member of the present invention is used, the lower end of the cylindrical metal body 3 is joined in an airtight manner, so that the inside of the vacuum processing chamber 18 can be corroded at a high vacuum of 10 ^-9 torr / sec or less. The inside of the cylindrical metal body 3 is completely brought into the atmosphere of the vacuum processing chamber 18 so that the inside of the cylindrical metal body 13 can be set to the high temperature state where the gas is introduced and the inside of the cylindrical metal body 13 can be set to the atmospheric atmosphere communicating with the outside. Since it can be cut off, it is possible to prevent the temperature detecting elements 22 and 23, the current-carrying terminal 21 and the conductor connected thereto from being exposed to corrosive gas.

However, in order to exhibit such an excellent effect, the distance L from the opening of the concave portion 1b of the plate-shaped ceramic body 1 to the stress relaxation ring 6 joined to the bottom surface of the concave portion 1b is set to 3 mm or less. Good.

This is because when the distance L from the opening of the recess 1b to the stress relaxation ring 6 exceeds 3 mm and becomes deep, the metal having a larger thermal expansion coefficient than the plate-shaped ceramic body 1 is provided near the opening of the recess 1b. Only intervening,
This is because cracks may occur in the ceramic portion forming the periphery of the opening of the recess 1b due to thermal stress. The thickness T and the width W of the stress relaxation ring 6 housed in the engagement portion 4 of the cylindrical metal body 3 are both preferably 2 mm or more. This is because when the thickness T and the width W are less than 2 mm, the effect of preventing the deformation of the flange 4 a of the tubular metal body 3 is poor, and preferably 5 mm or more. Note that the upper limit is not particularly limited, but may be set within a structurally allowable range.

Further, the thickness U of the flange 4a of the engaging portion 4 provided on the cylindrical metal body 3 is preferably as thin as possible from the viewpoint of reducing the stress caused by the difference in thermal expansion with the plate-like ceramic body 1. 0.0 mm or less. However, thickness U
Is smaller than 0.05 mm or less, the thickness U of the flange 4a is reduced.
Is preferably 0.05 to 2.0 mm, more preferably 0.1 to 2.0 mm.
A range of 2.0 mm is good.

In this embodiment, the ceramics forming the plate-shaped ceramic body 1 are Al
Ceramics containing at least one of the main components such as ₂ O ₃ , AlN, ZrO ₂ , SiC, and Si ₃ N ₄ can be used. Among them, alumina ceramics containing 99% by weight or more of Al ₂ O ₃ as a main component and sintering aids such as SiO ₂ , MgO, CaO, etc., and AlN With a main component of 0.5 to 20 as an oxide of a Group 2a element or a Group 3a element of the periodic table.
Either aluminum nitride ceramics containing up to 99% by weight or high-purity aluminum nitride ceramics containing 99% by weight or more of AlN as a main component is suitable.

The material of the stress relaxation ring 6 is as follows.
Any material such as metal or ceramic may be used as long as the difference in thermal expansion coefficient from the plate-shaped ceramic body 1 is within 2 × 10 ⁻⁶ / ° C. or less. It is preferable to use ceramics of the above, preferably ceramics having the same composition as the plate-shaped ceramic body 1.

Further, as the material of the tubular metal body 3, a metal having a high corrosion resistance against corrosive gas and a high plasma resistance and having a thermal expansion difference of 6 × 10 ⁻⁶ / ° C. or less from the plate-like ceramic body 1 is used. Preferably, it is used. Thermal expansion difference is 6 × 10 ^-6 /
If the temperature exceeds ℃, cracks are likely to occur at the bonding interface of ceramics immediately after brazing. In particular,
W, Mo, Ni, Al, Cu, Ti, Fe-Ni-Co
An alloy, an Fe—Ni alloy, or the like can be used.

Further, as the material of the brazing material,
Al, Cu, Pt, P besides u-based and NiCr-based brazing materials
A brazing material mainly composed of d and In can be used, and with these brazing materials, a sufficient bonding strength can be maintained even when a thermal cycle is repeatedly applied under a high temperature condition of 650 ° C. or more. At the same time, it is preferable that oxygen does not pass therethrough. However, under the condition of 600 ° C. or lower, a brazing material mainly composed of Ag can be used.

FIG. 2 shows an example in which the stress relieving ring 6 and the engaging portion 4 of the cylindrical metal body 3 are joined with a brazing material. The stress relaxation ring 6 may be fitted into the engaging portion 4 with the width being equal to or slightly smaller than the width W of the stress relaxation ring 6.

As described above, the present embodiment has been described with reference to the example of the wafer support member. However, the present invention is not limited to this embodiment, and the ceramic member and the metal member may be formed by brazing. It goes without saying that the present invention can be applied to a joined body of a ceramic member and a metal member of any shape as long as the joined body is formed by joining.

[0036]

EXAMPLE As an example of the present invention, a wafer support member shown in FIG. 1 was experimentally manufactured.

The plate-shaped ceramic body 1 has a diameter of about 220 m.
It was formed of a high-purity aluminum nitride ceramic having a disk shape of m and an AlN content of 99.9% by weight. The plate-shaped ceramic body 1 is obtained by mixing the primary raw material of AlN with methanol and pulverizing the mixture to an average particle size of 1 μm.
% Organic binder was added to form a slurry. This slurry was granulated with a spray dryer to produce a predetermined granulated powder. Then, using the granulated powder, a compact formed by embedding an internal electrode 2 made of molybdenum (Mo) as a heater electrode was formed, and the compact was hot-press sintered. The hot pressing conditions were 1910 ° C. and 20 ° C.
0 kg / cm ² .

When the characteristics of the aluminum nitride ceramics forming the plate-shaped ceramic body 1 were examined, the specific gravity was 3.26 g / cm ³ , which was a sufficient sintering density with respect to the theoretical density. The expansion coefficient was 5 × 10 ⁻⁶ / ° C.

On the other hand, the cylindrical metal body 3 has a thermal expansion coefficient of 8 ×
Formed of an Fe-Ni-Co alloy at 10 ^-6 / ° C,
The dimensions are 150 mm outside diameter and 0.5 m wall thickness.
m, the thickness U of the flange 4a of the engaging portion 4 having a U-shaped cross section is 0.5 mm, and the width between the flanges 4a is 11.1.
mm.

Further, the stress relaxation ring 6 was formed of the same high-purity aluminum nitride ceramics as the above-mentioned plate-shaped ceramic body 1, and the dimensions thereof were a ring having a thickness T of 5 mm and a width W of 11 mm.

The width of the concave portion 1b of the plate-shaped ceramic body 1 was 12.1 mm, and the depth of the concave portion 1b was 5.5 mm.

Thereafter, the plate-shaped ceramic body 1, the cylindrical metal body 3, and the stress relaxation ring 6 are joined by brazing, but Au-Ni is previously added to the recess 1b of the plate-shaped ceramic body 1 and the stress relaxation ring 6. 1050 ° C using -V brazing material
A metallized layer is formed at a temperature of .mu., And a stress relaxation ring 6 is formed on the bottom surface of the concave portion 1b of the plate-shaped ceramic body 1 by Au-Ni.
After fixing with brazing using a V-type brazing material,
The flanges 4a provided on the engaging portions 4 of the cylindrical metal body 3 are inserted into gaps between the b and the stress relaxation ring 6, respectively.
It was brazed and fixed using a Ni-V-based brazing material.

Therefore, He gas is supplied to the cylindrical metal body 3 of the wafer support member 1 and the presence or absence of a leak from the joint between the plate-shaped ceramic body 1 and the cylindrical metal body 3 is determined using a He gas leak detector. Upon measurement, no gas leakage was observed in the wafer support member of the present invention, and the wafer support member was in a good bonding state.

On the other hand, the conventional wafer supporting member shown in FIG. 3 and the wafer supporting member previously proposed by the present applicant shown in FIG. 5 were formed of the same material forming the wafer supporting member of the present invention. Gas leakage was observed, and a gap was generated between the plate-shaped ceramic body 11 and the flange 13a of the tubular metal body 13 immediately after brazing.

Next, several wafers having different distances L from the opening of the concave portion 1b of the plate-shaped ceramic body 1 to the stress relaxation ring 6 are prepared for the wafer support member of the embodiment of the present invention. The wafer support member is hermetically installed in the vacuum processing chamber 18 of the CVD apparatus, and a He gas leak detector is used to determine the presence or absence of a gas leak after applying a heat cycle from normal temperature to 850 ° C. 50 times at a heating rate of 15 ° C./min. It measured using.

The results are as shown in Table 1.

[0047]

[Table 1]

As a result, the concave portion 1b of the plate-like ceramic body 1
The distance L from the opening to the stress relaxation ring 6 is 3.0
If it was not more than mm, no gas leak was observed even after adding the thermal sieve 50 times, and it was confirmed that the joint had sufficient bonding strength.

[0049]

As described above, according to the present invention, an engaging portion having a substantially U-shaped cross section of a metal member is inserted into a recess provided in a ceramic member, and the cross section of the metal member has a substantially U shape. A stress relief member having a thermal expansion difference of not more than 2 × 10 ⁻⁶ / ° C. or less from the ceramic member is disposed in the U-shaped engagement portion, and the ceramic member, the metal member, and the stress relief member are each brazed. To form a joined body of a ceramic member and a metal member by brazing at a temperature of 900 ° C. or more, or by repeatedly applying a heat cycle in a very high temperature range from ordinary temperature to 650 ° C. or more. However, it is possible to effectively prevent a gap from being formed in the joint between the ceramic member and the metal member, and to prevent the engaging portion of the metal member from being peeled off, thereby greatly improving the durability of the joint.

Further, according to the present invention, an annular concave portion is provided on the lower surface of a plate-shaped ceramic body having a wafer mounting surface, and a cross-sectional shape provided on one end side of the cylindrical metal body in the concave portion is substantially U-shaped. And a thermal expansion difference between the plate-shaped ceramic body and the plate-like ceramic body is 2 × 10 ⁻⁶ /
900 ° C. or higher by providing a stress relaxation ring having a temperature of not more than 0 ° C. and forming the wafer support member by bonding the plate-shaped ceramic body, the tubular metal body, and the stress relaxation ring with a brazing material. Even if the brazing is performed at a temperature of or a thermal cycle is repeatedly applied in a very high temperature range from room temperature to 650 ° C. or more, a gap is formed between the engagement portion of the plate-shaped ceramic body and the cylindrical metal body. In addition, it is possible to effectively prevent the engaging portion of the cylindrical metal body from peeling off, and to prevent the occurrence of gas leak. Therefore, it is possible to maintain a high degree of vacuum in the vacuum processing chamber, and to prevent the current-carrying terminals and the temperature detecting elements provided in the cylindrical metal body and the conductors connected thereto from being exposed to the corrosive gas, and to prevent a long term. It can be a usable wafer support member.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an example in which a joined body of a ceramic member and a metal member of the present invention is applied to a wafer supporting member for holding a semiconductor wafer.

FIG. 2 is an enlarged sectional view showing a joint structure between a plate-shaped ceramic body and a cylindrical metal body in the wafer support member of the present invention.

FIG. 3 is a cross-sectional view showing a state where a conventional wafer support member is installed in a vacuum processing chamber.

FIGS. 4A and 4B are enlarged cross-sectional views for explaining a damaged state at a joint between a plate-shaped ceramic body and a cylindrical metal body in a conventional wafer support member.

FIG. 5 is a cross-sectional view showing a state in which the wafer support member previously proposed by the present applicant is installed in a vacuum processing chamber.

[Explanation of symbols]

1, 11 ... plate-shaped ceramic body 1a, 11a ...
Mounting surface 1b: annular concave portion 2, 12: internal electrode 3,
13 ... cylindrical metal body 4 ... engaging part 5 ... flange part 6, 24 ...
Stress relaxation ring 17 ・ ・ ・ O-ring 18 ・ ・ ・ Vacuum processing chamber 21 ・ ・
・ Electrification terminals 22, 23 ・ ・ ・ Temperature detecting element 30 ・ ・ ・ Semiconductor wafer

Claims (2)

[Claims] A metal member provided with a substantially U-shaped cross section and having a thermal expansion difference of 2 × with respect to the ceramic member within the concave portion of the ceramic member. A joined body of a ceramic member and a metal member, wherein a stress relaxation member of 10 ⁻⁶ / ° C. or less is provided, and the ceramic member, the metal member, and the stress relaxation member are respectively joined by a brazing material. 2. An upper surface of a plate-shaped ceramic body is used as a wafer mounting surface, and an annular concave portion is formed on a lower surface thereof. And a stress relaxation ring having a thermal expansion difference of not more than 2 × 10 ⁻⁶ / ° C. with respect to the plate-shaped ceramic body is disposed in the engagement portion. A wafer support member, wherein a plate-shaped ceramic body, a cylindrical metal body, and a stress relaxation ring are respectively joined by a brazing material.