JP2003142567A - Wafer mounting stage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wafer mounting stage in which particles are not produced, an electrostatic chuck part and a conductive base member can be bonded accurately, sufficient insulation is ensured between an electrostatic attraction electrode and the conductive base member, and the bonded part is not stripped even if heat cycle is repeated. SOLUTION: When the wafer mounting stage 1 is manufactured by bonding the conductive base member 10 to the electrostatic chuck part 5 provided with an electrostatic attraction electrode 4 on the surface opposite to the wafer W mounting surface 3 of a planar ceramic body 2, an insulating film 7 having a thickness S of 5-100 μm is bonded to the lower surface of the electrostatic chuck part 5 to cover the electrostatic attraction electrode 4 through a first organic adhesive layer 6 of 5-50 μm thick having Young's modulus of 29. 4 MPa-100 GPa, the planarity of the insulating film on the electrostatic attraction electrode 4 is set not higher than 100 μm, and the insulating film 7 and the conductive base member 10 are bonded through a second organic adhesive layer 8 having a thickness R of 50-500 μm an Young's modulus of lower than 29.4 MPa.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to CVD, PVD,
Addition of film forming equipment such as sputtering and etching equipment
Holds an object to be adsorbed such as a semiconductor wafer in a processing device
It relates to a wafer mounting stage. 2. Description of the Related Art Conventionally, a process for manufacturing a semiconductor integrated circuit
Has a thin film on a semiconductor wafer (hereinafter simply referred to as a wafer).
Film forming equipment to form and etching equipment to perform etching processing
Such semiconductor manufacturing equipment is used.
The semiconductor manufacturing wafer is held in the conductor manufacturing equipment.
A mounting stage is used. FIG. 5 shows a conventional wafer mounting stage.
1 shows a schematic sectional view of a semiconductor manufacturing apparatus. This semiconductor manufacturing apparatus includes a wafer mounting stay
The nozzle 51 is hermetically sealed in the vacuum processing chamber 70 via the O-ring 72.
The wafer mounting stage 51 is
The upper surface of the box-shaped body 52 is placed on the mounting surface 5 on which the wafer W is mounted.
3 and a pair of electrostatic absorption
An electrostatic chuck portion 55 having a wearing electrode 54;
A conductive base joined to the lower surface of the mixed plate 52
A pair comprising a member 60 and provided in the electrostatic chuck portion 55
DC power supply 74 is electrically connected to the electrostatic attraction electrode 54
Then, a positive and negative voltage is applied between
Generates electric force to attract and fix the wafer W to the mounting surface 53 by suction.
I was supposed to. [0005] The inside of the conductive base member 60 is cold.
A suction passage 61 is formed, and the suction
Applying processing such as film formation and etching to the wafer W that has been attached and held
The wafer W is at or above a predetermined processing temperature due to the heat generated
In order to prevent the cooling medium
Of heat, the heat of the wafer W is transferred to the electrostatic chuck portion 5.
5 to the conductive base member 60 to release the wafer.
The temperature of W was kept at a predetermined processing temperature. Then, using such a semiconductor manufacturing apparatus,
To apply processing such as film formation and etching to the wafer W,
As described above, the wafer W is attracted to the wafer mounting stage 51.
The counter electrode provided above the vacuum processing chamber 70 in a fixed state
The pole 71 and the conductive base member of the wafer mounting stage 51
A high frequency of 13.56 MHz is applied between 60 and 60
By generating plasma in the vacuum processing chamber 70
In both cases, a film forming gas and an etching gas
By supplying the gas, film formation processing and etching on the wafer W are performed.
It had to be subjected to ching processing. Note that in the figure, 73
Is a high frequency between the counter electrode 71 and the conductive base member 60.
A high frequency power supply for applying a voltage;
5 and the conductive base member 60 are made of a corrosive gas.
A protection ring that protects from direct exposure. Further, a wafer mounting stage 51 is formed.
The electrostatic chuck 55 and the conductive base member 60 are as follows.
It has been proposed to join by various means. Japanese Unexamined Patent Publication (Kokai) No. 63-283037 discloses FIG.
As shown in FIG. 6, the mounting surface 53 of the electrostatic chuck 55
On the opposite surface, a rubber-like
Through an organic adhesive layer 56 of silicon carbide, alumina, etc.
Silicone rubber with high thermal conductivity
Or about 0.2-0.3mm thick made of fluoro rubber etc.
The elastic insulator 57 is adhered, and the elastic insulator 5
7 and the conductive base member 60 are formed of a rubber-like organic adhesive layer.
A structure bonded through 56 has been proposed. Further, Japanese Patent Application Laid-Open No. 5-347352 discloses
The mounting surface 5 of the electrostatic chuck portion 55 as shown in FIG.
3 so as to cover the electrostatic attraction electrode 54 on the surface on the opposite side.
Through an organic adhesive layer 58 made of a polyimide resin
Insulation made of polyimide film about 25μm thick
The film 59 is adhered, and the insulating film 59
And the conductive base member 60 are made of a polyimide resin.
A structure in which the layers are bonded via an organic adhesive layer 58 has been proposed.
I have. [0010] However, Japanese Unexamined Patent Publication No. Sho 63
As disclosed in Japanese Patent Publication No.
The insulator 57 has a thickness of about 0.2 to 0.3 mm.
In the case of rubber and fluorine rubber, the electrode 54 for electrostatic adsorption and the conductivity
The withstand voltage between the base member 60 and the elastic insulator 58 is small.
Can damage and generate electrostatic force and plasma
There was a problem that it disappeared. Also, silicon forming the elastic insulator 57
Rubber and fluoro rubber are used in film forming gas and etching gas.
Reacts with fluorine, oxygen, and chlorine-based corrosive gases
In response, it becomes a low-boiling compound and evaporates gradually.
However, at this time, the silicon carbide mixed in the elastic insulator 57
Fillers such as silicon and alumina react with the above corrosive gas
Becomes nonvolatile and contaminates wafers as particles
There was also a problem to do. On the other hand, Japanese Patent Application Laid-Open No. 5-347352 discloses
In the technique shown, the electrostatic chuck 55 and the conductive base
Insulating film 5 having a thickness of about 25 μm between member 60
9 are interposed between the electrode 54 and the electrostatic attraction electrode 54.
Although sufficient insulation between the conductive base member 60 and the conductive base member 60 can be obtained.
However, the electrostatic chuck 55, the insulating film 59, and the
Both the edge film 59 and the conductive base member 60 are high
Adhesive layer 58 made of polyimide-based adhesive having a high rate
The wafer mounting stage 51
When the temperature changes, the electrostatic chuck 55 is formed.
Between the ceramic plate 52 and the conductive base member 60
The electrostatic chuck 5 is formed by the stress generated by the difference in thermal expansion.
5 is warped and the wafer W can be held accurately.
When the temperature cycle is repeated,
Peeling occurs between the electro-chuck portion 55 and the organic adhesive layer 58.
There was a problem that it occurred. [0013] Accordingly, the present invention relates to the above-mentioned section.
In consideration of the problem, one main surface of the ceramic plate
Equipped with an electrode for electrostatic attraction on the other main surface
And the other main part of the ceramic plate
Wafer mounting consisting of a conductive base member bonded to the surface side
In the placement stage, the other main plate of the ceramic plate
The surface has a thickness of 5 to 50 so as to cover the electrostatic attraction electrode.
μm and the Young's modulus is 29.4 MPa to 100 GPa
5 to 100 through the first organic adhesive layer
Adhesive insulating film of μm
The flatness of the insulating film located at
And the insulating film and the conductive base member
Having a thickness of 50 to 500 μm and a Young's modulus of 29.
Adhesion via a second organic adhesive layer of less than 4 MPa
It is characterized by having done. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described.
explain. FIG. 1 shows a wafer mounting stage according to the present invention.
1 is a schematic sectional view showing a semiconductor manufacturing apparatus according to the present invention. In this semiconductor manufacturing apparatus, a vacuum processing chamber 20 is provided.
The wafer mounting stage 1 is hermetically sealed via an O-ring 22
The wafer mounting stage 1 is an electrostatic chuck.
And a conductive base member 10. The electrostatic chuck 5 includes a ceramic plate 2
A mounting surface 3 on which a wafer W such as a semiconductor wafer is mounted.
And a conductor is provided on the lower surface of the ceramic plate 2
A pair of electrostatic attraction electrodes 4 composed of layers
You. The conductive base member 10 is made of aluminum.
Or super steel, or these metals and ceramic materials
And has a cooling passage 11 therein.
At the same time, lead wire 9 connected to electrode 4 for electrostatic attraction
A through hole 12 for taking out is formed. The lower surface of the electrostatic chuck 5 is
First organic adhesive so as to cover the pair of electrostatic adsorption electrodes 4
While bonding the insulating film 7 via the agent layer 6,
The insulating film 7 and the conductive base member 10 are
Wafer placement by bonding via organic adhesive 8
The stage 1 is constituted by the insulating film 7.
Between the electrostatic attraction electrode 4 and the conductive base member 10
It keeps insulation. Then, the pair of electrodes for electrostatic attraction 4 are respectively
Is connected to the DC power supply 24, and when a voltage is applied, the wafer W
A potential difference occurs between the electrodes 4 for electrostatic attraction, and the wafer W is mounted.
It can be fixed to the surface 3 by suction. Reference numeral 13 is formed on the wafer mounting stage 1.
Lift pin insertion hole, and the wafer W
Lift pins 26 for loading and lifting
Noh is arranged. Further, on the outer peripheral portion of the wafer mounting stage 1,
Is maintained so as to surround the exposed surfaces of the organic adhesive layers 6 and 8.
Protection ring 25 is installed, and the organic adhesive layers 6 and 8
Exposed surface is corrosive gas such as fluorine gas or chlorine gas or plasma
It is prevented from being directly attacked by ma. Further, a guide is provided above the inside of the vacuum processing chamber 20.
The counter electrode 21 facing the conductive base member 10 is installed.
There is a high frequency power supply 23 between them, for example, 13.56.
By applying a high frequency of MHz to the vacuum processing chamber 20,
Can generate plasma, and at the same time,
By applying a bias between them
I can do it. At this time, it is exposed to plasma
The heat generated in the wafer W by the
Heat transmitted to the conductive base member 10 and flowing to the cooling passage 11
Escape from the wafer mounting stage 1 to the outside via the medium,
Efficiently cools the wafer W sucked and fixed on the mounting surface 3
It has become. FIG. 2 shows a wafer mounting stage according to the present invention.
As shown in the cross-sectional view for explaining the main part of FIG.
In order to adsorb the wafer W to the wafer 3, a pair of electrostatic attraction electrodes
A voltage of 100 to 3 kV is applied between four. Therefore conductive
Efficient insulation between the conductive base member 10 and the electrode 4 for electrostatic attraction
Must have been. However, the electrode 4 for electrostatic attraction
And applying an insulator between the conductive base member 10 and
Is likely to cause defects such as bubbles in the applied insulator,
In order to cause insulation breakdown based on bubbles,
There's a problem. Therefore, the insulation processed in advance into a film shape
It is important to use an insulating film 7 having a high proof stress.
You. The material of the insulating film 7 is
Mid, polycarbonate, polyethylene terephthalate
G, polybutylene terephthalate, polyamide imide,
Has heat resistance of 100 ° C or more such as polyether sulfone
And withstand voltage of 10 kV / mm ^Two Above, mechanical strength
The higher the degree and rigidity, the better
The use of the rubber 7 reduces the elongation,
Because it does not stretch, it can be bonded flat, so it is preferable
No. However, the thickness T of the insulating film 7 is 5 μm.
m, a voltage of 100 V is applied between the pair of electrostatic attraction electrodes 4.
When the voltage is applied, the insulation film 7 may be broken down.
And the thickness T of the insulating film 7 is 100 μm.
m, the difference in thermal expansion between the ceramic plate 2 and
Therefore, when bonded, the ceramic plate 2 is deformed,
The flatness of the insulating film 7 deteriorates. Moreover, the thickness T
When the thickness is large, the heat transfer becomes poor, and the cooling efficiency of the wafer W is reduced.
There is a risk of lowering. Therefore, the thickness T of the insulating film 7 is 5 to 5.
The thickness is preferably 100 μm. Also, after the insulating film 7 is bonded,
The flatness of the insulating film 7 located on the suction electrode 4 is
The thickness is preferably 100 μm or less. This is because it is located on the electrostatic attraction electrode 4.
If the flatness of the insulating film 7 exceeds 100 μm,
The conductive base member 10 is interposed via the second organic adhesive layer 8.
When bonding, air is applied to the concave portion on the insulating film 5.
Is likely to accumulate, which may cause poor adhesion.
In the event of poor adhesion, partial heat cycle
And finally peeled off. In addition,
The flatness of the preferred insulating film 7 is 60 μm or less.
You. The thickness S of the first organic adhesive layer 6 is
The thickness is preferably 5 to 50 μm. The reason for this is that
When the thickness S of the adhesive layer 6 exceeds 50 μm, the thickness S varies.
The roughness increases, and the flat surface of the attached insulating film 7
It is difficult to reduce the degree to 100 μm or less.
The conductive base member 10 is interposed via the second organic adhesive layer 8.
When bonding, air is applied to the concave portion on the insulating film 5.
Is likely to accumulate, which may cause poor adhesion.
In the event of poor adhesion, partial heat cycle
And finally peeled off. Also,
When the thickness S of the organic adhesive layer 6 is less than 5 μm, the first
Air bubbles easily enter the organic adhesive layer 6 of the
The first organic adhesive layer 6 peels off
It is. Further, the first organic adhesive layer 6
The rate is preferably set to 29.4 MPa to 100 GPa. That is, the Young's modulus of the organic adhesive layer 6 is 2
When the pressure is less than 9.4 MPa, the insulating film 7 is adhered.
Then, when bonding the second organic adhesive layer 8,
Since the rigidity of the mechanical adhesive layer 6 is low, the second organic adhesive
It is difficult to suppress the variation of the thickness R of the agent layer 8,
As a result, from the conductive base member 10 to the electrostatic attraction electrode 4
Because the variation in the distance of
If the Young's modulus of the adhesive layer 6 exceeds 100 GPa,
When the insulating film 7 is bonded to the lamic plate 2,
The ceramic plate 2 changes due to the difference in thermal expansion between the two.
And the flatness of the insulating film 7 deteriorates.
You. By the way, the first characteristic having the above-mentioned characteristics is provided.
For the mechanical adhesive layer 6, an epoxy adhesive or the like may be used.
Can be. On the other hand, the wafer mounting stage 1 of the present invention
The second organic adhesive layer 8 comprises a conductive base member 10
For absorbing the difference in thermal expansion between the ceramic and the ceramic plate 2
The flatness of the mounting surface 3 changes even when a heat cycle is applied.
It is difficult to change and it is designed to prevent peeling,
For this purpose, the Young's modulus of the second organic adhesive layer 8 is set to 29.4.
MPa or less and the thickness R is 50 to 500.
It is good to be μm. That is, the Young's modulus of the second organic adhesive layer 8
Is 29.4 MPa or more, the wafer mounting stage 1
When the temperature changes, the flatness of the mounting surface 3 changes,
This is because peeling of the organic adhesive layer 8 occurs. The thickness R of the second organic adhesive layer 8 is
When the thickness is less than 50 μm, the conductive base member 10 and the ceramic
It is possible to sufficiently absorb the difference in thermal expansion between the
No, the ceramic plate 2 is deformed by the heat cycle
This changes the flatness of the mounting surface 3 and
The organic adhesive layer 8 is broken and partially peeled off,
This is because there is a possibility that the entire surface will be peeled off.
The thickness R of the second organic adhesive layer 8 exceeds 500 μm
Between the ceramic plate 2 and the conductive base member 10
The heat transfer coefficient decreases, and the temperature of the wafer W is immediately lowered.
Because of the inability to do so, for example,
In the etching process, an etching pattern is formed.
Of the remaining resist film, and after etching
Problems such as the inability to remove the resist film
Because. By the way, the second characteristic having the above-mentioned characteristics is provided.
Silicone adhesive, rubber-based adhesive
Agents and the like can be used. However, if the adhesive is a condensation type
In this case, curing proceeds by hydrolysis, but the wafer
Since page 1 has a large bonding area, hydrolysis reaches the center.
It is not performed and cannot be completely cured. like this
In such cases, it is preferable to use a thermosetting type as the adhesive.
It can be cured by heat over the entire surface of the adhesive surface.
Wear. By joining under these conditions, static
From the electrostatic chucking electrode 4 of the electric chuck portion 5 to the conductive base portion
The variation in the distance to the material 10 should be 100 μm or less.
And the electrostatic chuck 5 and the conductive base member 10
Can be joined with high accuracy. Note that, in the wafer mounting stage 1 of the present invention,
Is the thermal conductivity between the first and second organic adhesive layers 6, 8
In order to enhance the quality of the first or second organic adhesive layer 6, 8,
And fillers such as silicon carbide, alumina, aluminum nitride, etc.
Or the first and second organic adhesive layers 6, 8
To improve the viscosity and heat resistance of
Although fillers such as mosquito and carbon may be added,
If the amount of added is too large, the first and second organic
When the adhesive layers 6 and 8 are exposed to corrosive gas and volatilized,
Contains up to 1% by volume to cause tickle
Just do it. Next, manufacture of the wafer mounting stage 1 of the present invention.
The method will be described. First, to manufacture the electrostatic chuck section 5,
Prepare a ceramic plate 2 and lap the upper and lower surfaces
To form the mounting surface 3 on which the wafer W is mounted on the upper surface.
In both cases, the lower surface is finished to a flatness of 80 μm or less. here
The flatness of the lower surface of the ceramic plate 2 to 80 μm.
What is raised is the electrode 4 for electrostatic attraction and the conductive base member 10.
In order to reduce the variation in the distance to 100 μm or less.
You. Next, vapor deposition is performed on the lower surface of the ceramic plate 2.
Method, sputtering method, CVD method, plating method, etc.
A pair of semi-circular electrodes 4 for electrostatic adsorption as shown in FIG.
Is formed to manufacture the electrostatic chuck portion 5. The material of the electrode 4 for electrostatic adsorption is a ceramic.
Smaller than the volume resistivity of the material forming the
Any resistance value may be used. Ni, Ti, Al, Au, Ag,
Use of metals such as Cu, carbon or DLC
Can be. In addition, brazing or metallurgy using Mo or Ag
It may be formed by a size. However, the thickness Q of the electrostatic attraction electrode 4 is set to be equal to 0.
The thickness is preferably from 01 to 100 μm. That is, electrostatic absorption
If the thickness Q of the worn electrode 4 is less than 0.01 μm, the internal resistance
Is too large to be used as an electrode,
In addition, the thickness Q of the electrostatic attraction electrode 4 exceeds 100 μm.
And a first organic material interposed between the pair of electrostatic adsorption electrodes 4
Since defects such as bubbles easily occur in the system-based adhesive layer 6,
is there. In addition, the preferable thickness Q of the electrode 4 for electrostatic attraction is 0.1.
It is 1 μm to 10 μm. On the other hand, the conductive base member 10 is prepared,
The flatness of the joint surface with the electric chuck part 5 is set to 80 μm or less.
I will raise it. The reason for this is that the electrostatic chuck 5
In the distance from the electrode 4 for use to the conductive base member 10
This is to reduce the key length to 100 μm or less. Next, a first organic adhesive such as an epoxy adhesive is used.
Put the adhesive in a container, 15 minutes under reduced pressure of 2700Pa or less
After defoaming the adhesive by holding
The adhesive is dripped at the center of the ceramic plate 2 in a single character.
A 5 to 100 μm insulating film 7 is placed on the
The film 7 is gradually brought into close contact with the center. At this time, rubber
Apply adhesive from the center to the outer periphery of the insulating film 7 with a roller
It is only necessary to press down and make close contact. Next, a 20 m thick
m, an alumina platen with a flatness of 10 μm
With the shim on, apply for about 12 hours at a temperature of 100 ° C.
The adhesive is cured by heating and has a thickness of 5 to 50 μm.
m and the Young's modulus is 29.4 MPa to 100 GPa.
Bonding the insulating film 7 via the first organic adhesive layer 6
The flat surface of the insulating film 7 located on the electrostatic attraction electrode 4
The flatness is set to 100 μm or less. The insulating film 7 and the first organic
Use a transparent or translucent adhesive layer 6
Preferably, a transparent or translucent material is used.
Of the air bubbles remaining in the first organic adhesive layer 6
The presence or absence can be checked to prevent insulation failure effectively.
Can be Thereafter, the bonding surface of the conductive base member 10
Screen with a second organic adhesive such as silicone adhesive
After printing, the electrostatic chuck part on which the insulating film 7 is attached
5 on the mounting surface 3 of the electrostatic chuck portion 5 and a thickness of 20 m.
m, a flat plate made of alumina with a flatness of 10 μm
In a vacuum of 2700 Pa or less with weights stacked
To remove the second organic adhesive by holding for 15 minutes or more.
After foaming, heat at 100 ° C for about 12 hours
By hardening the second adhesive, the thickness is 50 to
500 μm and Young's modulus is less than 29.4 MPa
FIG. 4 is a diagram showing a state in which the second organic adhesive layer 8 is used for bonding.
1 can be manufactured.
You. The embodiment of the present invention has been described above.
However, it is not limited to only the above-described embodiment,
Can be improved or changed without departing from the gist of the present invention
Needless to say. (Embodiment 1) A wafer mounting stage shown in FIG.
Electrostatic adsorption when the thickness T of the insulating film 7 is varied
In the distance from the electrode 4 for use to the conductive base member 10
G, flatness of the mounting surface 3 at room temperature and during heating, and mounting during cooling
An experiment to check the temperature of the mounting surface 3 and the insulation of the joint
Was done. First, as a starting material, the main component
For mina powder, TiO _Two : 6% by weight and MgO: 3% by weight
%, SiO _Two : 2% by weight, CaO: 3% by weight
The mixed raw material powder is mixed and ground with a ball mill,
Slurry by adding indder, toluene, butyl acetate, etc.
After fabricating the
Green sheets, and laminate these green sheets.
Baked at 1600 ° C. for 2 hours in a reducing atmosphere
Ceramics made of alumina sintered body
After that, the outer diameter is 198mm with a diamond whetstone,
It was processed to a thickness of 1 mm to obtain a ceramic plate 2. Next, the upper surface of the ceramic plate 2 is
To form the mounting surface 3 of the wafer W
And the lower surface is also wrapped to achieve a flatness of 80 μm.
After that, the titanium shown in FIG.
The pair of electrostatic attraction electrodes 4 having a thickness Q of about 0.3 μm
Formed. Next, at a viscosity of 50 Pa · s,
Bonding with 12GPa elongation and 6% elongation
Put the agent in a container and reduce the pressure to 2700 Pa or less for 15 minutes or more.
The adhesive was defoamed by holding it up. Then
Is applied to the center of the lower surface of the ceramic plate 2 by one letter.
Made of polyimide with different thickness as shown in Table 1
Insulation with rubber roller after placing insulating film 7
The adhesive from the center of the conductive film 7 to the periphery
After pressing down and making close contact, thickness 20mm, flatness 10
Place a μm alumina platen on the insulating film 7 and further
In a 100 ° C oven with a weight
After heating the adhesive for half an hour to cure the adhesive,
Heat in an oven for 12 hours to cure the adhesive.
Only through the first organic adhesive layer 6 of 5 to 50 μm.
The edge film 7 was adhered. The position on the electrostatic attraction electrode 4 at this time is
The flatness of the insulating film 7 to be placed was measured. Next, a conductive base member made of aluminum
After setting the flatness on the bonding surface of No. 10 to 80 μm or less,
The adhesive surface has a viscosity of 1300 Pa · s
Of a thermosetting silicone adhesive with a
After printing, the electrostatic chuck provided with the insulating film 7
On the mounting surface 3 of the electrostatic chuck portion 5,
Place an alumina platen of 0 mm and flatness of 10 μm,
With a flat weight placed on the
Degas the adhesive by holding it in the air for at least 15 minutes.
Was. Then, heat it in an oven at a temperature of 100 ° C for 12 hours.
The thickness R is 350 μm by curing the adhesive
With an insulating film 7 via a certain second organic adhesive layer 8
Wafer as sample by bonding to conductive base member 10
The mounting stage 1 was manufactured. Then, the wafer mounting stage 1
Distance from electrostatic attraction electrode 4 to conductive base member 10
And the flatness of the mounting surface 3 were measured. In measuring the flatness of the mounting surface 3,
Is measured with a Kyocera flatness meter Nanoway.
In addition, conductive from the electrostatic attraction electrode 4 of the wafer mounting stage 1
The variation in the distance to the conductive base member 10 is shown in FIG.
As shown in FIG.
Cut in two directions of degree, 4 outside diameter measurement points, and intermediate measurement
A total of eight electrostatic adsorption electrodes 4 at four points
The distance to the base member 10 is measured with a tool microscope, and
The smallest difference was measured as variation. The mounting surface 3 of the wafer mounting stage 1
500W infrared lamp placed 50cm away
When the mounting surface 3 is heated to 50 ° C.
The flatness of the mounting surface 3 was measured. Further, the mounting surface 3 of the wafer mounting stage 1
For 5 hours to bring the temperature of the mounting surface 3 to 70 ° C.
Water at a temperature of 20 ° C. is supplied to the cooling passage 11 of the conductive base member 10.
Water is passed at a rate of 6 liters / minute, and the temperature of the
The temperature was measured with a surface thermometer, and the cooling characteristics were examined. Next, the electrostatic force is applied to the wafer mounting stage 1.
Assuming that plasma is generated, the conductive base member 1
0 and a voltage of 5 kV between the electrostatic attraction electrode 4
An experiment for investigating the insulating properties was performed. The results are as shown in Table 1. [Table 1] As can be seen from Table 1, the insulating film 7
Sample No. having a thickness T of 3 μm. 1 is a conductive base part
A voltage of 5 kV was applied between the material 10 and the electrostatic attraction electrode 4
However, the insulating film 7 was damaged. When the thickness T of the insulating film 7 is 120
In Sample No. 7 having a thickness of μm, the temperature of the mounting surface 3 during cooling was
As large as 38.9 ° C., there was a problem with the cooling rate. On the other hand, the thickness T of the insulating film 7 is
Sample Nos. 2 to 6 in the range of 5 to 100 μm
The distance between the attraction electrode 4 and the conductive base member 10
The roughness can be suppressed to 70 μm or less, and as a result,
The flatness of the mounting surface 3 could be reduced to 12 μm or less. The flatness of the mounting surface 3 after the heating is checked.
With large deformation, it is only 24 μm, which is about twice as large.
Thermal expansion between the lamic plate 2 and the conductive base member 10
It can be seen that the stress due to the tension difference can be effectively absorbed. Only
Also, when cooling after heating, the temperature of the mounting surface 3 should be 35 ° C or less.
The electrostatic chuck 5 and the conductive base.
Excellent heat transfer characteristics with the base member 10, and
5 kV between the conductive base member 10 and the electrostatic chucking electrode 4
Even if the voltage is applied, the insulating film 7 is not damaged,
Insulation was able to be maintained. (Example 2) Next, the thickness T of the insulating film 7 was set to 25 μm.
m and change the pressure to put on the first organic adhesive
Except that the thickness S of the first organic adhesive layer 6 is changed
Wafer mounting stage manufactured under the same conditions as in Example 1.
1 and the conductive base member 10 from the electrode 4 for electrostatic attraction.
Of the mounting surface 3 at room temperature and during heating
The flatness and the temperature of the mounting surface 3 during cooling are the same as in the first embodiment.
When measuring under the conditions and further applying a thermal cycle
An experiment was conducted to check for the presence or absence of peeling at the joints of. It should be noted that the joint was peeled off when subjected to a heat cycle.
For the presence / absence of separation, the wafer mounting stage 1
Heating and cooling are repeated at a rate of 1 ° C./min, and
A cooling cycle of 0 ° C. was applied. And every 50 cycles
First and second organic adhesive layers 6, 8 for ultrasonic testing
More observation was made to confirm the presence or absence of peeling. The results are as shown in Table 2. [Table 2] As can be seen from Table 2, the first organic adhesive
Sample No. 3 in which the thickness T of the agent layer 6 was 3 μm. 21 is the thickness
Air bubbles enter the first organic adhesive layer 6 because T is thin.
It is easy to repeat the thermal cycle due to this bubble,
The first organic adhesive layer 6 was peeled off in 0 cycles. The thickness T of the first organic adhesive layer 8 is
Sample No. exceeding 100 μm. For 26 and 27, insulation
The flatness of the film 7 exceeds 100 μm, and as a result,
The conductive base member 10 is interposed via the second organic adhesive layer 8.
The wafer mounting stage 1 is peeled off even if it is bonded.
Could not be achieved. On the other hand, the thickness of the first organic adhesive layer 8
Sample No. T having only T in the range of 5 to 100 μm. 22-2
5 is from the electrode 4 for electrostatic attraction to the conductive base member 10
Can be suppressed to 70 μm or less,
As a result, the flatness of the mounting surface 3 should be 12 μm or less.
Was completed. The flatness of the mounting surface 3 after the heating is checked.
And large deformation, as small as 20 μm, ceramic
Due to the difference in thermal expansion between the plate 2 and the conductive base member 10,
It can be understood that the stress that can be effectively absorbed. And heating
During subsequent cooling, the temperature of the mounting surface 3 is cooled to 35 ° C or less.
The electrostatic chuck part 5 and the conductive base member
Excellent heat transfer characteristics were obtained when the ratio was 10 or less. Further, even if the heat cycle is repeated, the first
The organic adhesive layer 6 has been used for a long time
Could be used. (Example 3) Next, the thickness T of the insulating film 7 was set to 25 μm.
m and the thickness S of the first organic adhesive 6 is 5
５０50 μm, and the second organic adhesive 8 is applied.
The thickness R of the second organic adhesive layer 8 by changing the pressure
C manufactured under the same conditions as in Example 2 except that they differ.
The same experiment as in Example 2 was performed using the EHA stage 1.
Was. The results are as shown in Table 3. [Table 3] As can be seen from Table 3, the second organic adhesive
The sample No. in which the thickness R of the agent layer 8 was 40 μm. 31 is
Thermal expansion between the lamic plate 2 and the conductive base member 10
Since the stress due to the tension difference cannot be relieved,
Of the mounting surface 3 was greatly deformed to 35 μm.
In addition, when a heat cycle is added, the first 50 cycles
Peeling of the second organic adhesive layer 8 occurred. The thickness R of the second organic adhesive layer 8 is
Sample No. exceeding 500 μm. 38 is the second organic system
Since the thickness of the adhesive layer 8 is large, the temperature of the mounting surface 3 after cooling is
As large as 41.9 ° C., there was a problem with the cooling rate. On the other hand, the thickness of the second organic adhesive layer 8
Sample No. R having a R of 50 to 500 μm. 32 ~
Reference numeral 37 denotes a portion extending from the electrostatic attraction electrode 4 to the conductive base member 10.
The variation in the distance at 70 μm or less
As a result, the flatness of the mounting surface 3 is set to 12 μm or less.
I was able to. The flatness of the mounting surface 3 after heating is checked.
And 26μm with large deformation, ceramic
Due to the difference in thermal expansion between the plate 2 and the conductive base member 10,
It can be understood that the stress that can be effectively absorbed. And heating
During subsequent cooling, the temperature of the mounting surface 3 is cooled to 35 ° C or less.
The electrostatic chuck part 5 and the conductive base member
Excellent heat transfer characteristics were obtained when the ratio was 10 or less. Further, even if the heat cycle is repeated, the second
Peeling is observed in the organic adhesive layer 8 for a long time.
Could be used. (Example 4) Next, the thickness T of the insulating film 7 was set to 25 μm.
m and the thickness S of the first organic adhesive layer 6
A second organic adhesive set within a range of 5 to 50 μm;
The thickness of the layer 8 is set in the range of 50 to 500 μm,
Example except that the Young's modulus of the organic adhesive layer 6 was changed.
Using wafer mounting stage 1 manufactured under the same conditions as
The same experiment as in Example 2 was performed. The results are as shown in Table 4. [Table 4] As can be seen from Table 4, the first organic adhesive
Sample No. 2 in which the Young's modulus of the layer 6 was less than 29.4 MPa.
Reference numeral 41 denotes a second organic system after bonding the insulating film 7.
When bonding the adhesive layer 8, the rigidity of the first organic adhesive layer 6
The second organic adhesive layer 8 has a thickness R
It is difficult to suppress the fluctuation, and as a result,
Variation in the distance from the pole 4 to the conductive base member 10
It was as large as 81 μm. The Young's modulus of the first organic adhesive layer 6
No. exceeds 100 GPa. 46 is ceramic
When the insulating film 7 is bonded to the plate 2,
Due to the difference in thermal expansion, the ceramic plate 2 is deformed,
The flatness of the edge film 7 exceeded 100 μm. The result
As a result, the conductive base member 10 is formed on the second organic adhesive layer 8.
Even when trying to join the wafer, the wafer mounting stage 1
I couldn't make it. On the other hand, the first organic adhesive layer 6
Testing rate is in the range of 29.4 MPa to 100 GPa.
Charge No. Reference numerals 42 to 45 denote a conductive base from the electrostatic attraction electrode 4.
Variation in the distance to the base member 10 is reduced to 70 μm or less.
As a result, the flatness of the mounting surface 3 is 12 μm.
m or less. The flatness of the mounting surface 3 after heating is checked.
And 26μm with large deformation, ceramic
Due to the difference in thermal expansion between the plate 2 and the conductive base member 10,
It can be seen that the effective stress can be effectively absorbed. And heating
During subsequent cooling, the temperature of the mounting surface 3 is cooled to 35 ° C or less.
The electrostatic chuck part 5 and the conductive base member
Excellent heat transfer characteristics were obtained when the ratio was 10 or less. Further, even if the heat cycle is repeated, the second
The organic adhesive layer 8 is used for a long time without peeling.
I was able to. (Example 5) Next, the thickness T of the insulating film 7 was set to 25 μm.
m and the Young's modulus of the first organic adhesive layer 6
Is 12 GPa, and the thickness S of the first organic adhesive layer 6 is
A second organic adhesive set within a range of 5 to 50 μm;
The thickness of the layer 8 is set in the range of 50 to 500 μm, and the second
Example except that the Young's modulus of the organic adhesive layer 8 was changed.
Using wafer mounting stage 1 manufactured under the same conditions as
The same experiment as in Example 2 was performed. The results are as shown in Table 5. [Table 5] As can be seen from Table 5, the second organic adhesive
Sample No. 8 in which the Young's modulus of the layer 8 exceeds 29.4 MPa 4
7, the ceramic plate 2 and the conductive base member 10
Stress due to the difference in thermal expansion between
And the flatness of the mounting surface 3 during heating was greatly deformed to 48 μm.
did. In addition, in the heat cycle test, 50 heat
The peeling of the second organic adhesive layer 8 occurs due to the cycle.
Was. On the other hand, the second organic adhesive layer 8
No. 2 having a modulus of 29.4 MPa or less. 48-5
0 is from the electrode 4 for electrostatic attraction to the conductive base member 10
Can be suppressed to 70 μm or less,
As a result, the flatness of the mounting surface 3 should be 12 μm or less.
Was completed. The flatness of the mounting surface 3 after heating is checked.
And large deformation, as small as 20 μm, ceramic
Due to the difference in thermal expansion between the plate 2 and the conductive base member 10,
It can be seen that the effective stress can be effectively absorbed. And heating
During subsequent cooling, the temperature of the mounting surface 3 is cooled to 35 ° C or less.
The electrostatic chuck part 5 and the conductive base member
Excellent heat transfer characteristics were obtained when the ratio was 10 or less. Further, even if the heat cycle is repeated, the second
Peeling is observed in the organic adhesive layer 8 for a long time.
Could be used. The thickness of the second organic adhesive layer 8 is
After the wafer mounting stage 1 is evaluated, the wafer mounting stage
Cut at a cross section passing through the center of the second organic adhesive layer 8
10 mm from the center and the outer periphery of the second organic adhesive layer 8.
The thickness was measured at five positions. The thickness of the first organic adhesive layer 7 is
The center of the ceramic plate 2 and the first organic adhesive layer 7
Were measured at five locations 10 mm from the outer circumference of the sample.
The whole plate-shaped ceramic body to which the above-mentioned insulating film 7 is bonded
From the thickness, the thickness of the ceramic plate and the insulating film 7
It was determined by subtracting the thickness of a certain polyimide sheet. As described above, according to the present invention, the ceramic
One main surface of the backing plate is used as the mounting surface on which the
And an electrostatic chuck having an electrostatic chucking electrode on the other main surface
Part and the other main surface side of the ceramic plate body
The wafer mounting stage consisting of the conductive base member
And the other main surface of the ceramic plate is
5 to 50 μm thick so as to cover the adsorption electrode
First rate of 29.4 MPa to 100 GPa
Insulating film having a thickness of 5 to 100 μm via a mechanical adhesive layer.
Glue the film and insulate it on the electrostatic attraction electrode
The flatness of the conductive film to 100 μm or less,
The insulating film and the conductive base member have a thickness of 50
５００500 μm and Young's modulus is less than 29.4 MPa
By adhering via a certain second organic adhesive layer,
Without generating particles and electrostatic chuck
To maintain sufficient insulation between the part and the conductive base member
Can be. Further, the electrostatic chuck portion is formed of a conductive base member.
Can be joined with high accuracy
Even if the cycle acts, the peeling of the bonding layer does not occur,
The wafer placed on the mounting surface can be held accurately.
You.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic sectional view showing a semiconductor manufacturing apparatus including a wafer mounting stage according to the present invention. FIG. 2 is a cross-sectional view illustrating a main part of a wafer mounting stage according to the present invention. FIG. 3 is a plan view showing an electrostatic attraction electrode provided on the wafer mounting stage of the present invention. FIG. 4 is a plan view showing measurement points for measuring a temperature of a mounting surface on a wafer mounting stage in an experiment. FIG. 5 is a schematic sectional view showing a semiconductor manufacturing apparatus provided with a conventional wafer mounting stage. FIG. 6 is a cross-sectional view illustrating an example of a conventional wafer mounting stage. FIG. 7 is a cross-sectional view showing another example of a conventional wafer mounting stage. [Description of Signs] 1: Wafer mounting stage 2: Ceramic plate 3: Mounting surface 4: Electrostatic chuck electrode 5: Electrostatic chuck 6: First organic adhesive layer 7: Insulating film 8: Second organic adhesive layer 9: Lead wire 10: Conductive base member 11: Cooling passage 12: Through hole 13: Lift pin insertion hole 20: Vacuum processing chamber 21: Counter electrode 22: O-ring 23: High frequency power supply 24: DC power supply 25: Protection ring 26: Lift pin W: Wafer

Claims (1)

Claims: 1. An electrostatic chuck portion having one main surface of a ceramic plate as a mounting surface on which a wafer is mounted, and an electrostatic chuck electrode on the other main surface; In a wafer mounting stage comprising a conductive base member joined to the other main surface of the ceramic plate, the other main surface of the ceramic plate has a thickness so as to cover the electrode for electrostatic attraction. Is 5-5
0 μm and Young's modulus of 29.4 MPa to 100 GP
a through the first organic adhesive layer which is a
A 0 μm insulating film is adhered, and the flatness of the insulating film located on the electrostatic adsorption electrode is set to 100 μm or less, and the thickness of the insulating film and the conductive base member is 50 to 500 μm, And the Young's modulus is 2
A wafer mounting stage bonded via a second organic adhesive layer having a pressure of less than 9.4 MPa.