JP2002141403A - Wafer supporting member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wafer supporting member which never has a plate-like ceramic material damaged even when a power supplying terminal is bonded or even if a high temperature heat cycle is repeatedly applied. SOLUTION: The wafer supporting member 1 has at least one inner electrode 3 (4) in the plate-like ceramic material 2 and has the power supplying terminals 6 and 7 electrically connected to the inner electrodes 3 and 4, on the surface of the plate-like ceramic material 2. In the surface of the plate-like ceramic material 2, a hole 2a is so formed as to expose part of the inside electrode 3 (4). On the inner wall face of the hole 2a, a conductor layer 16 having a continuity with the exposed part of the inner electrode 3 (4) is provided. The power supplying terminal 6 (7) is inserted and fixed in the hole 2a via at least one coil spring 17 to electrically connect the power supplying terminal 6 (7) and the conductor layer 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a wafer support member used to support a wafer such as a semiconductor wafer.

[0002]

2. Description of the Related Art Conventionally, in a semiconductor manufacturing process, a semiconductor wafer is subjected to an exposure process, a drawing process, a film forming process by PVD, CVD, sputtering, etc., an etching process by plasma etching, optical etching, etc., a dicing process, or various processing steps A wafer support member is used to support the semiconductor wafer during transfer to the semiconductor wafer.

FIG. 6 shows a state in which a conventional wafer support member is installed in a vacuum processing chamber.
1 is a plan view of a plate-shaped ceramic body 22 in which the upper surface of a disk-shaped plate-shaped ceramic body 22 is used as an installation surface 25 for a wafer W.
A pair of internal electrodes 2 for electrostatic attraction
3 has embedded therein internal electrodes 24 for heating on the lower surface side of the plate-shaped ceramic body 22, and has an internal electrode 23 for electrostatic attraction and an internal electrode for heating on the lower surface of the plate-shaped ceramic body 22. Feeding terminals 26 and 27 that are electrically connected to the electrodes 24, respectively, are joined.

The plate-shaped ceramic body 22 has a gas introduction hole 31 opened at the center of the installation surface 25, and the installation surface 25 is formed with a gas groove 32 communicating with the gas introduction hole 31. . Reference numeral 28 denotes a gas pipe which is joined to the lower surface of the plate-shaped ceramic body 22 and communicates with the gas introduction hole 31.

The wafer support member 21 is installed in a vacuum processing chamber 35 via a metal cylindrical support 29, and feed terminals 26, 2 provided on the wafer support member 21 are provided.
7 and the gas pipe 28 are prevented from being exposed to corrosive gas in the vacuum processing chamber 35. Reference numeral 34 denotes a plasma generation electrode provided above the vacuum processing chamber 35.

In order to perform various processes on the semiconductor wafer W with the wafer support member 21, the wafer W
Is applied and a DC voltage is applied between the pair of internal electrodes 23 for electrostatic attraction, so that a Coulomb force due to dielectric polarization and a Johnson-Rahbek force due to a small leakage current are applied between the wafer W and the internal electrodes 23. Express electrostatic attraction force of
The semiconductor wafer W on the installation surface 25 is forcibly adsorbed and fixed, and the heating internal electrode 24 is energized to heat the wafer W adsorbed and fixed on the installation surface 25, and the gas is supplied through a gas pipe 28. He is introduced from the introduction hole 31 into the space defined by the gas groove 32 on the installation surface 25 and the semiconductor wafer W.
By supplying such a gas, the wafer W is uniformly heated,
Further, a plasma is generated by applying a high-frequency voltage between the pair of internal electrodes 23 and the plasma generating electrode 34, and a film forming gas is supplied into the vacuum processing chamber 35 in this state. If a thin film can be formed, and an etching gas is supplied into the vacuum processing chamber 35, a fine circuit pattern can be formed on the wafer W. Further, a cleaning gas can be supplied into the vacuum processing chamber 35. When supplied, components adhering to the surface of the wafer support member 21 and the vacuum processing chamber 35 can be removed.

As means for joining the plate-shaped ceramic body 22 forming the wafer support member 21 and the power supply terminals 26 and 27, Japanese Patent Application Laid-Open No. Hei 5-101871 discloses, as shown in FIG. The electrode 23 (24) and the power supply block 42 electrically connected via the wire 41 are placed in a mold, and the mold is filled with a ceramic material and sintered by hot pressing. The internal electrodes 23 (2
4) and the power supply block 42 are integrally buried to produce a plate-shaped ceramic body 22, and the female screw portion 42 a of the power supply block 42 exposed on the surface of the plate-shaped ceramic body 22 is provided with the power supply terminal 26 (27). By screwing the male screw portion 26a (27b), the power supply terminal 26 (27) is
3 (24) has been proposed.

In Japanese Patent Application Laid-Open No. Hei 10-189696, as shown in FIG. 8, a hole 43 communicating with the internal electrode 23 (24) is formed in the lower surface of the plate-shaped ceramic body 2 and the hole 4 is formed.
After forming the metallized layer 44 on the power supply terminal 26 (2
7) is inserted, and brazing is performed via a brazing material layer 45.

[0009]

By the way, the wafer support member 21 shown in FIG. 6 has a heating internal electrode 24 for performing various processes such as film formation, etching and cleaning.
Is heated to 200 ° C. or more, and an electrostatic attraction force or plasma is generated in a state of being heated to such a high temperature. In the case of the structure having the bonding structure shown in FIG. Since the residual stress due to the difference in thermal expansion from the body 22 is large, the temperature is increased to 200 ° C. or more.
There is a problem that the plate-shaped ceramic body 22 is cracked and broken when the temperature is repeatedly lowered. In particular, the plate-shaped ceramic body 2 was easily broken at a heating temperature of 300 ° C. or more.

Further, in the wafer supporting member 21 having the bonding structure shown in FIG. 8, since the residual stress at the time of brazing is large, cracks occur starting from the corners of the holes 43 formed in the plate-shaped ceramic body 22. In addition, there is a problem that the plate-shaped ceramic body 22 is damaged.

[0011]

SUMMARY OF THE INVENTION In view of the above-mentioned problems, the present invention provides one of the main surfaces of a plate-shaped ceramic body as a mounting surface on which a wafer is placed, and at least one internal surface in the plate-shaped ceramic body. A wafer support member having electrodes and a power supply terminal electrically connected to the internal electrode on the surface of the plate-shaped ceramic body other than the installation surface; Is formed, a conductive layer is provided on the inner wall surface of the hole, and is electrically connected to the exposed portion of the internal electrode. The power supply terminal is inserted into the hole via at least one coil spring. Thus, the power supply terminal and the conductor layer are electrically connected.

The conductive layer preferably has a thickness of 5 to 50 μm. The material forming the coil spring may be stainless steel, Inconel, Hastelloy,
It is preferably made of any one of titanium or titanium alloy, copper or copper alloy.

The above internal electrodes can be used as electrodes for electrostatic attraction, electrodes for heating, and electrodes for plasma generation.

[0014]

Embodiments of the present invention will be described below.

FIG. 1 is a sectional view showing an example of a wafer support member according to the present invention installed in a vacuum processing chamber.

The wafer support member 1 is composed of a disk-shaped plate-shaped ceramic body 2, and the upper surface of the plate-shaped ceramic body 2 is used as a mounting surface 5 on which a semiconductor wafer W is mounted.
A pair of internal electrodes 3 for electrostatic attraction are embedded on the installation surface side in the plate-shaped ceramic body 2, and internal electrodes 4 for heating are embedded on the lower surface side in the plate-shaped ceramic body 2, respectively. On the lower surface of the plate-shaped ceramic body 2, there are provided power supply terminals 6, 7 electrically connected to the internal electrodes 3 for electrostatic attraction and the internal electrodes 4 for heating, respectively.

FIG. 2 is an enlarged sectional view showing a power supply structure of an internal electrode 3 (4) embedded in the plate-shaped ceramic body 2 and a power supply terminal 6 (7) electrically connected to the internal electrode 3 (4). As shown in the drawing, the lower surface of the plate-shaped ceramic body 2 has a hole 2a provided through the internal electrode 3 (4), and the inner wall surface of the hole 2a has one hole of the internal electrode 3 (4). The part is exposed.
Further, a conductor layer 16 is formed on the entire inner wall surface of the hole 2a, and the conductor layer 16 is electrically connected to the internal electrode 3 (4). Then, the power supply terminal 6 (7) is inserted into the hole 2a, and the insertion portion 6a (7) of the power supply terminal 6 (7) is inserted.
a) Two annular grooves 6b (7b) are formed on the outer circumference at an interval, and the two annular grooves 6b (7b)
The annular coil spring 17 shown in FIG.
The coil spring 17 has a size to be held in the annular groove 6b (7b) and has a diameter slightly larger than the outer diameter of the hole 2a. And this power supply terminal 6
When the insertion portion 6a (7a) of (7) is inserted into the hole 2a,
Since the coil spring 17 is pressed against the inner wall surface of the hole 2a by the elastic action, the power supply terminal 6 (7) can be fixed and held in the hole 2a, and the power supply terminal coil 6 (7) comes into contact with the conductor layer 16. Coil spring 17
Through the internal electrode 3 (4).

The plate-like ceramic body 2 has an installation surface 5
And a gas groove 12 communicating with the gas introduction hole 11 is formed on the installation surface 5. Reference numeral 8 denotes a metal gas pipe that is joined to the lower surface of the plate-shaped ceramic body 2 and communicates with the gas introduction hole 11.

Further, the wafer support member 1 is installed in a vacuum processing chamber 15 via a metal cylindrical support 9, and the upper surface of the cylindrical support 9 is in contact with the lower surface of the plate-like ceramic body 2. While airtightly joined via a brazing material layer (not shown),
The lower surface of the cylindrical support 9 is hermetically sealed with the vacuum processing chamber 15 via an O-ring (not shown). Therefore, the power supply terminals 6 and 7 and the gas pipe 8 provided on the wafer support member 1 are prevented from being exposed to the corrosive gas in the vacuum processing chamber 15. Reference numeral 14 denotes an electrode for plasma generation installed on the upper part of the vacuum processing chamber 15.

In order to perform various processes on the semiconductor wafer W with the wafer support member 1, the wafer W is placed on the installation surface 5 and a DC voltage is applied between the pair of internal electrodes 3 for electrostatic attraction. As a result, an electrostatic attraction force such as Coulomb force due to dielectric polarization or Johnson-Rahbek force due to a small leakage current is developed between the wafer W and the internal electrode 3, and the semiconductor wafer W on the installation surface 5 is forcibly attached. The wafer W fixed by suction to the installation surface 5 is heated by energizing the internal electrode 4 for heating while adsorbing and fixing, and is connected to the gas groove 12 of the installation surface 5 through the gas introduction hole 11 through the gas pipe 8. By supplying a gas such as He into the space formed by the semiconductor wafer W, the wafer W is uniformly heated, and a high-frequency voltage is applied between the pair of internal electrodes 3 and the plasma generating electrode 14. By If plasma is generated and a film forming gas is supplied into the vacuum processing chamber 15 in this state, a thin film can be formed on the wafer W, and if an etching gas is supplied into the vacuum processing chamber 15, A fine circuit pattern can be formed on the wafer W, and if a cleaning gas is supplied into the vacuum processing chamber 15, components adhering to the surface of the wafer support member 1 and the vacuum processing chamber 15 can be removed. Is available.

According to the wafer support member 1 of the present invention, the power supply terminal 6 (7) is pressed by the elastic action of the coil spring 17 so that the hole 2 of the plate-shaped ceramic body 2 is pressed.
a, the stress acting due to the difference in thermal expansion between the plate-shaped ceramic body 2 and the power supply terminal 6 (7) even if the high-temperature thermal cycle is repeatedly applied to the wafer support member 1. Since it can be absorbed by the elastic action of the spring 17, the plate-shaped ceramic body 2 can be securely fixed without generating cracks.

The plate-like ceramic body 2 and the power supply terminal 6
In consideration of the difference in thermal expansion from (7), a structure in which the coil spring 17 always abuts the power supply terminal 6 (7) and the hole 2a of the plate-shaped ceramic body 2 with an appropriate pressing force even when a thermal cycle is applied. By doing so, the power supply terminal 6 (7) can be electrically connected to the conductor layer 16 that conducts with the internal electrode 3 (4) via the coil spring 17,
The power applied to the power supply terminal 6 (7) is reliably
(7).

Therefore, if this power supply structure is used for connection between the internal electrode 3 for electrostatic attraction and the power supply terminal 6, it is assumed that a large voltage of 2 kV is applied to the power supply terminal 6 in order to generate an electrostatic attraction force. Can be reliably supplied to the internal electrodes 3 without a large power loss, an electrostatic attraction force having a desired magnitude can be exhibited, and a high frequency power of 2 kW for generating plasma is supplied to the power supply terminal 6. Can be reliably supplied to the internal electrode 3 without a large loss, so that uniform and uniform plasma can be generated with the other plasma generating electrode 14. If the structure is used for connection between the internal electrode 4 for heating and the power supply terminal 7, 20
Even if a voltage of 0 V is applied, the voltage can be reliably supplied to the internal electrodes 4 without a large loss, so that the wafer support member 1 can be heated to a predetermined temperature.

The conductive layer 16 formed on the inner wall surface of the hole 2a is preferably formed of a metal such as gold, silver, or aluminum or any of these alloys. If formed, the conductor layer 16
Can be reduced to 5 Ω or less, heat generation due to contact resistance with the coil spring 17 can be prevented even when a large current or voltage is applied, and it is difficult to corrode even when exposed to a high temperature in the atmosphere. Internal electrode 3 over a period
(4) Energization can be reliably performed.

However, when the thickness t of the conductive layer 16 is less than 5 μm, it is difficult to form the conductive layer 16 uniformly on the inner wall surface of the hole 2a because it is too thin. Because there is a possibility that it will be scratched and peeled off by the coil spring 17,
If the thickness t of the conductive layer 16 exceeds 50 μm,
This is because the stress due to the difference in thermal expansion between the plate-shaped ceramic body 2 and the plate-shaped ceramic body 2 increases, and the plate-shaped ceramic body 2 may be broken when the temperature is repeatedly increased and decreased.

Therefore, the thickness t of the conductor layer 16 formed on the inner wall surface of the hole 2a is preferably 5 to 50 μm. In addition, as a means for forming the conductor layer 16, a film forming means such as a metallizing method, a thermal spraying method, and a plating method can be used, but the thermal spraying method and the plating method are based on a difference in thermal expansion from the plate-like ceramic body 2. Since peeling may occur due to stress or stress received from the coil spring 17,
It is preferable to form the plate-like ceramic body 2 by a metallization method having a high adhesion strength.

The material forming the coil spring 17 is preferably a material having conductivity and having little deterioration in elasticity even when exposed to a high temperature. For example, stainless steel, Inconel, Hastelloy, titanium or titanium alloy, Alternatively, copper or a copper alloy can be used. Also, on the surface of the coil spring 17 made of the above material,
A conductor film made of gold, silver, nickel, or copper may be deposited. In this way, by depositing a conductor film having better conductivity than the material of the coil spring 17, a larger current or voltage can be obtained. Is applied, heat generation at the contact portion between the coil spring 17 and the conductive layer 16 can be suppressed, which is preferable.

The material of the coil spring 17 needs to be selected depending on the temperature at which the wafer support member 1 is used. For example, 300 ° C. or less when using any of stainless steel, titanium, and titanium alloy, 450 ° C. or less when using Inconel, 650 ° C. or less when using Hastelloy, and 150 ° C. or less when using copper or a copper alloy. . This is because if the temperature exceeds the above-mentioned temperature, the spring constant inherent to the material is deteriorated by heating, and if the power supply terminals 6 and 7 are repeatedly inserted and removed during maintenance, power is supplied into the hole 2 a formed in the plate-shaped ceramic body 2. When the terminals 6 and 7 are inserted, a sufficient spring effect by the coil spring 17 cannot be obtained, so that good energization cannot be obtained and the power supply terminals 6 and 7 may fall out of the hole 2a during use. Because there is.

If the wire diameter B of the coil spring 17 is smaller than 0.1 mm, a sufficient current or voltage cannot be supplied to the conductive layer 16, and the coil spring 17 itself generates heat to cause power loss. When the wire diameter B is larger than 0.4 mm, the original expansion and contraction effect of the spring cannot be utilized,
When the temperature rises, an excessive stress is applied to the hole 2a of the plate-shaped ceramic body 2 and the plate-shaped ceramic body 2 may be broken. Therefore, the coil spring 17 has a wire diameter B of 0.1.
It is preferable to use one having a range of up to 0.4 mm.

The dimensions of the coil spring 17, such as the coil diameter A and the inner diameter C, are determined by the insertion portions 6 a of the power supply terminals 6, 7.
7a, the size and shape of the annular grooves 6b, 7b
a, the plate-shaped ceramic body 2, the power supply terminals 6, 7,
In consideration of the thermal expansion coefficient of the coil spring 17 and an appropriate pressing force in the operating temperature range, the coil spring 17 may be appropriately selected and used so as to contact the inner wall surface of the hole 2a.

Further, as a material for forming the power supply terminals 6 and 7, due to the structure of the present invention, the coil spring 17 relieves and absorbs stress caused by a difference in thermal expansion between the plate-shaped ceramic body 2 and the power supply terminals 6 and 7. Therefore, an Fe—Co—Ni alloy, molybdenum, or tungsten, which is not restricted as in the conventional power supply structure and has a thermal expansion difference close to that of the ceramic forming the plate-shaped ceramic body 2, is used. Needless to say, a material such as gold, nickel, and copper having a relatively large thermal expansion difference with the plate-like ceramic 2 can be used, and may be appropriately selected and used according to a use temperature and a use environment.

The material for forming the plate-like ceramic body 2 forming the wafer support member 1 is not particularly limited, and may be silicon carbide, silicon nitride, aluminum nitride, or the like.
Ceramics containing alumina or the like as a main component can be used. Among them, ceramics containing aluminum nitride as a main component have excellent corrosion resistance and plasma resistance, and have high thermal conductivity. It is preferable in terms of achieving a uniform temperature. In particular, when exposed to a halogen-based gas used as an etching gas or a cleaning gas, the purity of aluminum nitride is 99.8.
% Or more is preferably used.

The material of the pair of internal electrodes 3 for electrostatic attraction embedded in the plate-shaped ceramic body 2 and the internal electrode 4 for heating is such that the difference in thermal expansion between the plate-shaped ceramic body 2 and the co-firing is small. It is preferable to use a metal such as tungsten or molybdenum having a high melting point or tungsten carbide.

Further, the material for forming the power supply terminals 7, (6), the pipe 12, or the ring body 13 is preferably a material having a small thermal expansion difference with respect to the plate-like ceramic body 2.
Metals such as tungsten, Fe-Ni-Co alloys and Ni
It is preferable to use a -Co alloy or the like.

Next, an example of another power supply structure provided in the wafer support member 1 according to the present invention will be described below.

In the power supply structure shown in FIG. 4, two annular grooves 2b for holding the coil spring 17 are formed in the plate-like ceramic body 2 in place of the insertion portions 6a (7a) of the power supply terminals 6, 7. Since the power supply structure is formed on the inner wall surface of the power supply structure 2a, the same effect as the power supply structure shown in FIG. 2 can be obtained.

In the power supply structure shown in FIG. 5, when the power supply terminals 6 and 7 are inserted into the holes 2a, the insertion portions 6a and 6a of the power supply terminals 6 and 7 are used.
Hole 2 opposing annular grooves 6b, 7b formed on the outer periphery of 7a
a, two annular grooves 2b are also formed on the inner wall surface of the
The coil spring 17 is disposed in the space formed by the power supply terminals 6 and 7 and the space formed by the environment groove 2b and the annular groove 7b. Dropout can be effectively prevented.

Although the embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment. For example, in the present embodiment, the coil spring 17 is used.
Although an example in which two are used is shown, it is sufficient that at least one coil spring 17 is used, and it is needless to say that the present invention is not limited to this and can be improved or changed without departing from the gist of the present invention.

[0039]

EXAMPLE A wafer support member 1 of the present invention having a power supply structure shown in FIG. 2 and a conventional wafer support member 21 having a power supply structure shown in FIG. , 24 were heated to heat the wafer support members 1, 21 to examine whether the plate-shaped ceramic bodies 2, 22 were damaged or not.

In this experiment, the plate-like ceramic bodies 2 and 22 forming the wafer supporting members 1 and 21 were made to have an AlN purity of 9%.
It was formed of a 9.8% aluminum nitride sintered body, and its shape was a disk-shaped body having an outer diameter of 200 mm and a plate thickness of 10 mm. The upper surfaces of the plate-like ceramic bodies 2 and 22 are used as the wafer mounting surfaces 5 and 25, and the mounting surfaces 5 and 2 are used.
At a depth of 5 to 0.5 mm, a pair of internal electrodes 3 and 23 made of tungsten for electrostatic adsorption are placed on the installation surfaces 5 and 2.
Internal electrodes 4 and 24 made of tungsten for heating were buried at a depth of 5 to 5 mm.

On the lower surfaces of the plate-shaped ceramics 2 and 22, holes 2a and 43 are formed to communicate with the pair of internal electrodes 3 and 23 and the internal electrodes 4 and 24, respectively.
Ag-Cu paste containing Ti is applied to the inner wall surface of
By baking at 850 ° C., conductor layers 16 and 44 made of a metallized layer are formed.
Conduction with 3, 24 was achieved. The hole 2a communicating with the internal electrode 3 for electrostatic attraction has a diameter of 5.05.
mm, depth 9.5 mm, internal electrode 4 for heating
The hole 2a communicating with the hole has a diameter of 5.05 mm and a depth of 7.5 m.
m.

In the wafer support member 1 of the present invention, the coil spring 17 is made of Hastelloy having a surface plated with gold, and has a coil diameter A of 1.42 m.
m and a wire diameter B of 0.18 mm and an inner diameter D of 2.9 mm.
Insertion portion 6 of power supply terminals 6 and 7 made of e-Co-Ni alloy
a, 7a fit into the annular grooves 6b, 7b formed on the outer periphery,
By inserting the insertion portions 6a and 7b of the power supply terminals 6 and 7 into the holes 2a of the plate-shaped ceramic body 2 and inserting them, the power supply terminals 6 and 7 are fixed to the plate-shaped ceramic body 2 by the pressing force of the coil spring 17. The wafer support member 1 of the present invention was manufactured. The outer diameter of the insertion portions 6a and 7b of the power supply terminals 6 and 7 was 4.82 mm, and the groove depth F of the annular grooves 6b and 7b formed in the insertion portions 6a and 7a was 0.9 mm.

In the wafer supporting member 1 of the present invention, the thickness t of the conductor layer 16 is set to 5 μm, 20 μm, 50 μm.
m, 100 μm, and 150 μm were prepared.

On the other hand, the conventional wafer support member 21 has a hole 43 in the plate-shaped ceramic body 22 on which the conductor layer 44 is formed.
The conventional wafer support member 1 was manufactured by inserting the power supply terminals 26 and 27 made of an Fe-Co-Ni alloy and brazing and fixing them using an Ag-Cu brazing material.

After the wafer supporting members 1 and 21 are set in the vacuum processing chamber, a current is supplied between the power supply terminals 7 and 27 while the wafer W is placed on the mounting surfaces 5 and 25 to heat the internal electrodes for heating. Heat cycle test A in which 4,24 is heated, the temperature is raised from 50 ° C. to 600 ° C. in 5.5 minutes, the temperature is maintained at 600 ° C. for 1 minute, and then the temperature is lowered to 50 ° C. in 5.5 minutes.
And the temperature was raised from 50 ° C. to 600 ° C. in 11 minutes.
After holding at this temperature for 1 minute, the heat cycle tests B in which the temperature is lowered to 50 ° C. in 11 minutes are separately performed, and a voltage of +250 V and a voltage of −250 V are respectively applied between the pair of power supply terminals 6 and 26. When an operation is performed to generate an electrostatic attraction force between the pair of internal electrodes 3 and 23 and the wafer W to reverse the polarity of the voltage applied between the pair of power supply terminals 6 and 26 every minute. Ceramic body 2, 2
The number of times until cracks occurred in No. 2 was measured for each heat cycle test.

The results are shown in Tables 1 and 2. Table 1 shows the results of the heat cycle test A, and Table 2 shows the results of the heat cycle test B.

[0047]

[Table 1]

[0048]

[Table 2]

As a result, in each of the thermal cycle tests, the plate-like ceramic body 2 of the conventional wafer support member 21 was damaged within 100 cycles.

On the other hand, the wafer support member 1 of the present invention
Indicates that the plate-shaped ceramic body 2 is not damaged up to 100 cycles and has excellent durability. In particular, the conductor layer 1
6 having a thickness of 5 to 30 μm,
Even after a heat cycle test of zero cycles, the plate-shaped ceramic body 2 was not damaged, indicating that it had extremely excellent durability.

As described above, it can be seen that the use of the wafer support member 1 of the present invention enables stable power supply to the internal electrodes 3 and 4 for a long time even under severe heat load conditions.

[0052]

As described above, according to the present invention, one main surface of the plate-shaped ceramic body is used as an installation surface on which a wafer is mounted, and at least one internal electrode is provided in the plate-shaped ceramic body. And a wafer support member having a power supply terminal electrically connected to the internal electrode on the surface of the plate-shaped ceramic body other than the installation surface, wherein a part of the internal electrode is formed on the surface of the plate-shaped ceramic body other than the installation surface. Is formed, a conductor layer is provided on the inner wall surface of the hole, and is electrically connected to the exposed portion of the internal electrode, and the power supply terminal is inserted into the hole via at least one coil spring. Since the power supply terminal is electrically connected to the conductor layer, even if a high-temperature thermal cycle is repeatedly applied, the thermal expansion difference between the plate-shaped ceramic body and the power supply terminal is reduced. Since stress generated I can be alleviated and absorbed by the coil spring, without damaging the ceramic plate, and a feeding terminal and the internal electrodes can be reliably conducted.

In particular, when the thickness of the conductive layer is set to 5 to 50 μm and the coil spring is made of any one of stainless steel, Inconel, Hastelloy, titanium or a titanium alloy, copper or a copper alloy, a power supply terminal is formed. It is possible to increase reliability for ensuring conduction with the internal electrodes.

Therefore, if the internal electrode is used as an electrode for electrostatic attraction, the wafer support member can be used as an electrostatic chuck, and the wafer can be firmly attracted and fixed to the installation surface. If the internal electrode is used as an electrode for heating, the wafer support member can be used as a heater, the wafer placed on the installation surface can be heated, and if the internal electrode is used as an electrode for plasma generation, It can be used as a susceptor, and can generate plasma with another plasma generating electrode provided on the installation surface.

As a result, if a film forming process or an etching process is performed by using the wafer supporting member of the present invention, highly accurate film forming or an etching can be performed over a long period of time. It is possible to repeatedly remove components adhering to the support member and the vacuum processing chamber.

[Brief description of the drawings]

FIG. 1 is a sectional view schematically showing a state in which a wafer support member of the present invention is installed in a vacuum processing chamber.

FIG. 2 is an enlarged cross-sectional view illustrating a power supply structure provided in the wafer support member of the present invention.

FIGS. 3A and 3B are views showing a coil spring used in a power supply structure provided in the wafer support member of the present invention, wherein FIG.
(B) is a front view.

FIG. 4 is an enlarged sectional view showing another power supply structure provided in the wafer support member of the present invention.

FIG. 5 is an enlarged sectional view showing still another power supply structure provided in the wafer support member of the present invention.

FIG. 6 is a cross-sectional view schematically showing a state where a conventional wafer support member is installed in a vacuum processing chamber.

FIG. 7 is an enlarged cross-sectional view illustrating an example of a power supply structure provided in a conventional wafer support member.

FIG. 8 is an enlarged sectional view showing another example of the power supply structure provided in the conventional wafer support member.

[Explanation of symbols]

1, 21: wafer support member 2, 22: plate-shaped ceramic body 3, 23: internal electrode for electrostatic attraction 4, 24: internal electrode for heating 5, 25: installation surface 6, 7, 26, 27: supply Terminal 6
a, 7a: insertion portion 6b, 7b: annular groove 8, 28: gas pipe 9, 2
9: cylindrical support 11, 31: gas introduction hole 12, 32: gas groove 14, 34: plasma generating electrode 15, 35: vacuum processing chamber 16: conductor layer 17: coil spring

Claims (4)

[Claims] 1. A plate-shaped ceramic body other than the mounting surface, wherein one main surface of the plate-shaped ceramic body is an installation surface on which a wafer is mounted, and at least one internal electrode is provided in the plate-shaped ceramic body. In a wafer support member having a power supply terminal electrically connected to the internal electrode on a surface thereof, a hole exposing a part of the internal electrode is formed on a surface of the plate-shaped ceramic body other than the installation surface, and the hole is formed. A conductive layer is provided on the inner wall surface of the conductive layer, the conductive layer being electrically connected to the exposed portion of the internal electrode, and the power supply terminal is inserted into the hole through at least one coil spring to electrically connect the power supply terminal and the metallized layer. A wafer support member, wherein the wafer support member is connected. 2. The wafer supporting member according to claim 1, wherein said conductive layer has a thickness of 5 to 50 μm. 3. The wafer supporting member according to claim 1, wherein said coil spring is made of any one of stainless steel, Inconel, Hastelloy, titanium or a titanium alloy, copper or a copper alloy. 4. The wafer according to claim 1, wherein the internal electrode is any one of an electrode for electrostatic attraction, an electrode for heating, and an electrode for plasma generation. Support members.