JP2000174105A - Semiconductor wafer holding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor wafer holding device holding a semiconductor wafer without deforming it and not preventing thermal conduction between the semiconductor wafer and a stage. SOLUTION: This device has three support protrusions 3 constraining a semiconductor wafer 2 in the direction vertical to the wafer surface, a stage 4 having the three support protrusions 3, and low-profile electrostatic chucks 1A, 1B elastically deformed in the direction vertical to the surface of the semiconductor wafer 2. The electrostatic chucks 1A, 1B are made by laminating and bonding organic elastic sheets having high electric resistance and high thermal conductivity and organic elastic sheets having low electric resistance and high thermal conductivity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor wafer holding device used for holding a semiconductor wafer on a stage in a semiconductor manufacturing process.

[0002]

2. Description of the Related Art Most of the current semiconductor manufacturing processes include:
It is performed under vacuum or low pressure conditions. Since a vacuum chuck cannot be used under such a vacuum or low pressure condition, an electrostatic chuck is used to hold a semiconductor wafer.

The electrostatic chuck utilizes the Coulomb force of a capacitor having a semiconductor wafer as one electrode and a metal provided inside the electrostatic chuck as the other electrode.
When such an electrostatic chuck is used, the semiconductor wafer is pressed against the surface of the electrostatic chuck by the electrostatic chucking force between the above-described electrodes, so that the semiconductor wafer is restrained in a direction perpendicular to the wafer surface. become. In addition, the semiconductor wafer is restrained so as not to be displaced in the direction of the wafer surface by the frictional force generated when the semiconductor wafer is pressed against the surface of the electrostatic chuck.

This will be described with reference to FIGS. 4A and 4B. For example, when the semiconductor wafer 2 is warped in a free state as shown in FIG. Thus, the semiconductor wafer is deformed in a direction in which the warpage of the semiconductor wafer is corrected by being attracted to the electrostatic chuck 1 ′, and is held in that state. In FIG. 4, reference numeral 1'a denotes an insulating film constituting the electrostatic chuck 1 ', 1'c denotes an electrode for the electrostatic chuck constituting the electrostatic chuck 1', and 5 denotes a high-voltage DC power supply.

In a general semiconductor manufacturing process, it is necessary to deform and hold a semiconductor wafer having a free state and a warp in a free state like the holding state by the electrostatic chuck described above (hereinafter, referred to as flattening holding). desirable. However, in some lithography processes, such as the manufacture of masks for X-ray exposure apparatuses typified by electron beam lithography, the semiconductor wafer must be held in a free state without deformation (hereinafter, referred to as non-deformation holding). However, it is indispensable to realize high position accuracy of drawing.

As a semiconductor wafer holding structure for holding a semiconductor wafer in an undeformed state as described above, a conventional structure shown in FIG.
As shown in (a) and (b), a three-point support system in which the semiconductor wafer 2 is placed on the support protrusions 3 provided on the stage 4,
As shown in FIGS. 6A and 6B, the semiconductor wafer 2 is mechanically sandwiched between the support protrusions 3 and the clamps 6 to be held.

However, in the former three-point support system,
The force that restrains the semiconductor wafer 2 so as not to be displaced in the plane direction of the wafer surface is only the frictional force and the Hertzian stress when the three support protrusions 3 contact the back surface of the semiconductor wafer 2,
Very small. For this reason, when the semiconductor wafer holding device is mounted on a moving stage such as an XY stage and acceleration is applied to the semiconductor wafer, the semiconductor wafer and the holding device, that is, the semiconductor wafer 2 and the support protrusion 3
There is a problem that slippage occurs between them and hinders positioning.

In the latter clamping method, the force for restraining the semiconductor wafer 2 so as not to be displaced in the plane direction of the wafer surface is strong and slipping is unlikely to occur, but the semiconductor wafer 2 is clamped by the clamping method, position and force. There is a problem that it is greatly deformed. In reality, it is difficult to hold the above-described semiconductor wafer in such a structure in an undeformed state.

For this reason, the applicant of the present invention simultaneously holds the above-mentioned undeformed state and a strong restraining force against the displacement of the semiconductor wafer in the plane direction of the wafer.
The invention disclosed in JP-A-6-132388 has been previously proposed. In this conventional example, as shown in FIG. 7, a semiconductor wafer 2 is provided with three support projections 3 provided below the wafer 2.
And a semiconductor wafer holding device (hereinafter, referred to as a hybrid holding mechanism) that holds the semiconductor wafer 2 with the thin electrostatic chucks 1A and 1B capable of elastic deformation. Such a hybrid holding mechanism,
It is excellent in non-deformation holding characteristics, and has a strong restraining force against displacement of the semiconductor wafer 2 in the surface direction.

In FIG. 7, reference numeral 7 denotes a rubber pad provided on the stage 4, and reference numeral 8 denotes a spacer provided on the stage 4 and made of an insulating material. These are to prevent the electrostatic chucks 1A and 1B from falling by their own weight during non-sucking, so that the distance between the chucks 1A and 1B and the wafer 2 is too large, and the chucks are not sucked even when a voltage is applied.

[0011]

However, in the hybrid holding mechanism having the above-described structure, the semiconductor wafer 2 is floated from the stage 4 by the three-point support structure by the support projections 3, and the semiconductor wafer 2 is placed on the back surface of the semiconductor wafer 2. The thin electrostatic chucks 1A and 1B that are in surface contact also have a small contact area and a very small cross-sectional area. For this reason, heat conduction between the semiconductor wafer 2 and the stage 4 is very poor in a vacuum, and the semiconductor wafer 2 is almost completely thermally isolated.

Therefore, after holding the semiconductor wafer 2 on the above-described hybrid holding mechanism, the semiconductor wafer 2
Has to be waited for several hours until the temperature of the stage 4 matches the temperature of the stage 4 and drawing becomes possible.

Further, since the amount of heat incident on the semiconductor wafer 2 during writing has increased due to the recent progress of the writing apparatus, the heat conduction between the semiconductor wafer 2 and the stage 4 has been improved, The structure must be such that the amount of heat incident on the stage 2 is well transmitted to the stage 4 side. If not, the temperature of the semiconductor wafer 2 excessively rises due to the amount of incident heat, which causes a problem of deteriorating the drawing accuracy.

Further, in the above-described conventional hybrid holding mechanism, a thin-film organic insulator is adhered to a thin-film metal, or an insulating material is welded to the thin-film metal.
On the contrary, thin-film electrostatic chucks 1A and 1B are formed by depositing or plating metal on a thin-film insulator.
Is formed. However, with such a structure, it has been difficult to efficiently manufacture the flat and thin electrostatic chucks 1A and 1B without warpage.

Further, since different materials are joined as described above, if the temperature at the time of manufacturing these thin electrostatic chucks 1A and 1B is different from the temperature actually used,
Thin electrostatic chuck 1A, depending on the difference in the coefficient of thermal expansion of the material,
There was also a problem that 1B was warped.

The present invention has been made in view of such circumstances, and holds a semiconductor wafer in an undeformed state, does not hinder heat conduction between the semiconductor wafer and a stage, and furthermore, has a movable stage. It is an object of the present invention to provide a semiconductor wafer holding device that can be easily manufactured without causing slippage between the semiconductor wafer and the stage side even when the method is applied.

[0017]

In order to meet the above-mentioned object, a semiconductor wafer holding apparatus according to the present invention comprises a stage having at least three support projections for restraining a semiconductor wafer on a wafer surface in a vertical direction. And a thin electrostatic chuck capable of being elastically deformed in a vertical direction on a wafer surface of the semiconductor wafer, wherein the thin electrostatic chuck is formed using an organic elastic material. It is characterized by.

Further, in the semiconductor wafer holding device according to the present invention, the thin electrostatic chuck is formed by using an organic elastic material sheet having high electric resistance and high thermal conductivity as an electric insulating layer, and a low electric resistance as an electrode layer. And an organic elastic material sheet having a high thermal conductivity, and by laminating and adhering these sheets. The semiconductor wafer holding device according to the present invention uses silicon rubber as a base material of the organic elastic material sheet, and uses silicon rubber as a base material of an adhesive used for laminating and bonding the sheets. It is characterized by the following.

Further, in the semiconductor wafer holding device according to the present invention, the thin electrostatic chuck is formed in the organic elastic material sheet by forming a slit opened at one edge.
It is characterized in that it is formed on the wafer surface so as to be elastically deformable in a vertical direction.

According to the present invention, when the elastically deformable thin electrostatic chuck is attracted to the back surface of the semiconductor wafer, the vertical force acting on the wafer surface acting on the back surface of the semiconductor wafer is caused by gravity and the support protrusion. Excluding the reaction force due to, the elastic force required to deform the thin electrostatic chuck by only the clearance between the semiconductor wafer and the thin electrostatic chuck and the weight of the thin electrostatic chuck, the direction perpendicular to the wafer surface To help. Here, if the above-described clearance is set to substantially “0” and the thin electrostatic chuck 1 has rigidity enough to support its own weight, these two forces become negligible. The semiconductor wafer is hardly deformed due to adsorption of the semiconductor wafer on the semiconductor wafer.

On the other hand, if the semiconductor wafer moves in the direction of the wafer surface, that is, in the XY plane, the thin electrostatic chuck is pulled, compressed, or twisted, and a large reaction force is generated. Then, since the semiconductor wafer is restrained so as not to move, no slippage occurs between the semiconductor wafer and the support protrusion.

Further, since the thin electrostatic chuck has a laminated structure composed of an organic elastic material sheet having high thermal conductivity,
If the adhesive layer is sufficiently thin and negligible, heat conduction between the back surface of the semiconductor wafer and the thin electrostatic chuck, inside the thin electrostatic chuck, and between the thin electrostatic chuck and the stage is good, so that the The overall heat conduction with the stage is also improved.

Further, if an adhesive having the same base material as that of the organic elastic material is used as the adhesive for bonding the electric insulating layer made of the organic elastic material sheet and the electrode layer, the coefficient of linear thermal expansion becomes almost the same. Even when the electrostatic chuck is used at a temperature different from that used when the electrostatic chuck is manufactured, the thin electrostatic chuck itself does not warp. In addition, according to the thin electrostatic chuck made entirely of an organic elastic material as described above, the thin electrostatic chuck can be cut into a desired shape using a water jet cutter after bonding in a laminated state. The manufacture of the chuck is simple.

According to the present invention, the thin electrostatic chuck constituting the hybrid holding mechanism is formed of an organic elastic material as described above, thereby holding the semiconductor wafer in an undeformed state, and It is possible to realize a semiconductor wafer holding device that is easy to manufacture without hindering heat conduction between the stage and sliding between the semiconductor wafer and the holding device.

[0025]

FIG. 1 shows a first embodiment of a semiconductor wafer holding device according to the present invention. FIG. 1 (a) is a plan view, FIG. 1 (b) is a front view, and FIG. (c) is a plan view of the external shape of the thin electrostatic chuck.

Prior to the description of FIG. 1, the principle of operation of the semiconductor wafer holding device of the hybrid type according to the present invention will be described with reference to FIG. Note that FIG.
2A is a plan view of the hybrid holding mechanism, FIG. 2B is a front view, and FIG. 2C is a cross-sectional view showing a detailed structure of the thin electrostatic chuck.

2 (a), 2 (b) and 2 (c), reference numeral 1 denotes a thin electrostatic chuck, which has a high electric resistance as shown in FIG. 2 (c). And electrical insulating layers 1a and 1e made of an organic elastic material sheet having high thermal conductivity, an electrode layer 1c made of an organic elastic material sheet having low electric resistance and high thermal conductivity, and an organic elastic material equivalent to these. It is composed of adhesive layers 1b and 1d.

The reason why the organic material is used for the electric insulating layers 1a and 1e as insulators in the thin electrostatic chuck 1 is to increase the dielectric constant and the Coulomb force. The reason why the electric insulating layer 1e as an insulator is provided also on the stage 4 side is to prevent a short circuit with another metal such as the stage 4.

Here, as shown in FIG. 2C, one end in the longitudinal direction of the thin electrostatic chuck 1 is fixed to the free end, and the other end is fixed to the stage 4 in the direction of arrow BB 'in the figure. Are easy to move, and hard to move in the direction of arrows CC ′ in the figure. Reference numeral 5 in FIG. 2B denotes a high-voltage DC power supply connected between the electrode layer 1c of the electrostatic chuck 1 and the semiconductor wafer 2 via the stage 4 as a conductor and the support protrusion 3. In FIG. 2B, in the thin electrostatic chuck 1, a solid line indicates a state at the time of suction, and a broken line indicates a state at the time of non-suction.

In such a configuration, the semiconductor wafer 2
When the elastically deformable thin electrostatic chuck 1 is attracted to the back surface of the semiconductor wafer 2, the force in the Z direction acting on the back surface of the semiconductor wafer 2 excludes the gravity and the reaction force by the support protrusion 3, Of the thin electrostatic chuck 1 and the weight of the thin electrostatic chuck 1 in the one Z direction. At this time, if the clearance d is set to substantially “0” and the thin electrostatic chuck 1 has rigidity enough to support its own weight, these two forces become negligible. The deformation of the semiconductor wafer due to the electric chuck 1 being attracted to the semiconductor wafer 2 hardly occurs.

On the other hand, if the semiconductor wafer 2 attempts to move in the plane direction of the wafer surface, that is, in the XY plane, the thin electrostatic chuck 1 is pulled, compressed, or twisted. Since a force is generated and the semiconductor wafer 2 is restrained so as not to move, no slippage occurs between the semiconductor wafer 2 and the support protrusion 3.

As described above, the thin electrostatic chuck 1 is composed of the organic elastic material sheets 1a and 1a having high thermal conductivity.
e; 1c, if the adhesive layers 1b, 1d are sufficiently thin and negligible, between the back surface of the semiconductor wafer 2 and the thin electrostatic chuck 1, in the thin electrostatic chuck 1, and in the thin electrostatic chuck 1 Since any heat conduction between the semiconductor wafer 2 and the stage 4 is good, the overall heat conduction between the semiconductor wafer 2 and the stage 4 is much better than in the prior art.

Further, organic elastic material sheets 1a, 1e having a high electric resistance and a high thermal conductivity for an electric insulating layer.
If an organic elastic material sheet 1c having a low electric resistance and a high thermal conductivity for the electrode layer and the adhesive (adhesive layers 1b, 1d) used for these are used with the same base material, linear heat Since the coefficient of expansion is almost the same, the thin electrostatic chuck 1 does not warp even when used at a temperature different from that at the time of manufacture.

In the thin electrostatic chuck 1 made entirely of an organic elastic material, the thin electrostatic chuck 1 can be cut into a desired shape using a water jet cutter after laminating and bonding. The manufacture of the electric chuck 1 becomes extremely simple. Further, when the thin electrostatic chuck 1 is made of an organic elastic material in this manner, it has the heat conduction of the organic elastic material and can exhibit the soft property.

As described above, by forming the thin electrostatic chuck 1 of the hybrid holding mechanism from an organic elastic material,
The semiconductor wafer 2 is held in an undeformed state, does not hinder thermal conduction between the semiconductor wafer 2 and the stage 4, does not slip between the semiconductor wafer 2 and the holding device, and is easy to manufacture. A certain semiconductor wafer holding device can be realized.

According to the present invention, based on such an operation principle, a semiconductor wafer holding device is shown in FIGS.
The configuration is as shown in FIG. Here, this embodiment exemplifies a case where two thin electrostatic chucks 1 are used to form a bipolar electrostatic chuck.

In the figure, reference numerals 1A and 1B denote thin electrostatic chucks, and reference numeral 2 denotes a semiconductor wafer. As shown in FIG. 2 (c), the thin electrostatic chucks 1A and 1B are provided with organic elastic material sheets 1a and 1e having high electric resistance and high thermal conductivity, and low electric resistance and high thermal conductivity. It is formed by laminating and bonding an organic elastic material sheet 1c having the same. Reference numeral 5 denotes a high-voltage DC power supply that supplies a predetermined DC voltage to each of the electrode layers 1c of the thin electrostatic chucks 1A and 1B. Reference numeral 3 denotes a support protrusion made of a conductor or an insulator provided on the stage 4.

According to the semiconductor wafer holding device configured as described above, first, the semiconductor wafer 2 is left on the three support projections 3. Thus, the semiconductor wafer 2 is supported at three points by the support protrusions 3. Here, the positions of the support projections 3 are configured in advance so as to minimize the deformation of the semiconductor wafer 2 due to its own weight. The portions corresponding to the respective support projections 3 of the thin electrostatic chucks 1A and 1B include:
An insertion hole or an insertion groove is formed.

When voltages 10E and 1E are applied from the high-voltage DC power supply 5 to the thin electrostatic chucks 1A and 1B, respectively, the thin electrostatic chucks 1A and 1B form a bipolar electrostatic chuck with respect to the semiconductor wafer 2. Therefore, each of the thin electrostatic chucks 1A and 1B is elastically deformed and
Adsorbs on the back of As a result, the semiconductor wafer 2 is restrained within the wafer surface so as not to be displaced in the direction of the wafer surface.

In this embodiment, the clearance d between the semiconductor wafer 2 and the thin electrostatic chucks 1A and 1B is 4
0 μm, which is sufficiently small, and is also a thin electrostatic chuck 1A,
1B is hard enough to support its own weight,
Since the thickness is determined, the constraint in the vertical direction is the same as in the case of only three-point support.

In this embodiment, the electric insulating layer 1
a, 1e, thickness 0.2mm, hardness 70 (JIS-
A), volume resistivity 1E + 14Ωcm, thermal conductivity 1.1W
A silicon rubber sheet having a high electrical resistance of / m ° C and a high thermal conductivity is used. Further, the electrode layer 1c has a thickness of 1 mm, a hardness of 70 (JIS-A), and a volume resistivity of 5E-3.
A silicon rubber sheet having a low electrical resistance of Ωcm and a thermal conductivity of 2.3 W / m ° C. and a high thermal conductivity is used.

Here, the silicone rubber sheet (1)
The electrical resistance of the silicon rubber forming a, 1e; 1c) is increased or decreased, and the heat conduction is increased by adding an additive (filler) such as Ag, Cu, C, etc. to the silicon rubber. Can be obtained.
The reason for using silicon rubber for such a semiconductor wafer holding device is that it has the advantage that it hardly becomes an impurity even if it volatilizes in a semiconductor manufacturing device, and that its volume change is small even in a vacuum.

Further, the above-described silicone rubber sheet (1)
a, 1e; 1c) are laminated and bonded to form the thin electrostatic chucks 1A, 1B, since a silicone rubber-based adhesive is used.
A and 1B can be regarded as a pure silicon rubber sheet having a thickness of 1.4 mm. Therefore, such thin electrostatic chucks 1A and 1B do not warp even if the temperature during manufacture and the temperature during use are different.

The combined thermal conductivity of the thin electrostatic chucks 1A and 1B is approximately 2.0 W / m ° C., which is about twice that of general soda glass and 1/10 that of titanium. As shown in FIG. 1A, if the thin electrostatic chucks 1A and 1B are brought into contact with the back surface of the semiconductor wafer 2 in as large an area as possible, heat conduction between the semiconductor wafer 2 and the stage 4 is sufficient for practical use. Can be obtained.

Further, as shown in FIG. 1 (c), semi-circular notches 11A are formed in opposing side edges of the thin electrostatic chucks 1A and 1B provided substantially corresponding to the half of the semiconductor wafer 2, respectively. , 11B, and these notches 11A, 11B are provided.
By forming slits 12A and 12B open at the side edges of B and dividing it into a plurality of elastically deformable portions, the thin electrostatic chuck 1
Since the actual contact area of A and 1B with the semiconductor wafer 2 can be increased, heat conduction is further improved.

The present invention is not limited to the structure described in the above embodiment, and it goes without saying that the shape, structure, etc. of each part can be appropriately modified or changed. For example, in the above-described embodiment, the silicone rubber sheet (1a, 1
e; 1c) is used because there is almost no outgassing in a vacuum and it is suitable for a semiconductor manufacturing process. However, the present invention is not limited to this and has similar characteristics. Needless to say, it may be formed of other types of materials.

Also, in this embodiment, the thin electrostatic chuck 1 has a three-layer structure except for the adhesive layer as in FIG. 2C. It is also possible to omit the insulating layer 1e and to have a two-layer structure except for the adhesive layer.

In this embodiment, the support projections 3 for restraining the semiconductor wafer 2 in a direction perpendicular to the wafer surface are provided.
Are provided on the back side of the semiconductor wafer 2, but a structure in which the support protrusions 3 are provided on the front side of the semiconductor wafer 2, for example, as in the second embodiment shown in FIG. In this case, a leaf spring 9 for pressing the semiconductor wafer 2 against the support protrusion 3 is newly required.

In the second embodiment shown in FIG. 3, the reason why the shape and strength of the leaf spring 9 are adjusted to realize the non-deformation characteristic equivalent to that of the first embodiment shown in FIG. Although difficult, other features are the same as in the embodiment of FIG. According to the second embodiment, since the height reference is the surface of the semiconductor wafer 2, there is an advantage that the drawing surface height does not change even if the thickness of the semiconductor wafer 2 changes.

In each of the above-described embodiments, the semiconductor wafer 2 is supported on the stage 4 using the three support projections 3. However, the present invention is not limited to this. Any structure can be used as long as it can support the device in an upward state, and the number of support protrusions should be at least three or more.

[0051]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In a semiconductor wafer holding apparatus constructed as in the first embodiment in FIG. 1, a bare silicon wafer having a diameter of 3 inches (weight 21
g), when the thin electrostatic chucks 1 </ b> A and 1 </ b> B are not used and three points are supported only by the support protrusions 3, X
When a voltage of E = ± 500 V was applied to the thin electrostatic chuck 1 while the restraining force was about 10 g in both the axial and Y-axis directions, the restraining force was about 100 g in both the X-axis and Y-axis directions. there were.

In a semiconductor manufacturing process, the maximum acceleration of a moving stage used in a lithography process for forming a resist pattern on a substrate is 0.5 to 1 G, and the semiconductor wafer 2 weighing 21 g does not slip. Requires a binding force of 10.5 to 21 g or more.

Therefore, the semiconductor wafer 2 is supported
If only three points are supported by only the thin electrostatic chucks 1A and 1B described above, slippage occurs, but no slippage occurs. At this time, the semiconductor wafer 2 before and after the thin electrostatic chucks 1A and 1B are sucked.
According to the Fizeau interferometer, the amount of deformation was less than １ ／ fringe (0.16 μm), and the effect of adsorption was not observed.

[0054]

As described above, the semiconductor wafer holding apparatus according to the present invention holds the semiconductor wafer in an undeformed state, and does not hinder the heat conduction between the semiconductor wafer and the stage. A semiconductor wafer holding device applicable to the stage can be easily realized.

Therefore, according to the present invention, in the lithography process for manufacturing a semiconductor, excellent effects such as the fact that it can contribute to the realization of high drawing position accuracy can be obtained.

[Brief description of the drawings]

FIG. 1 shows a first embodiment of a semiconductor wafer holding device according to the present invention.
FIGS. 3A and 3B are diagrams showing an embodiment of the present invention, in which FIG.
3 is a front view, and FIG. 3C is a plan view of the outer shape of the thin electrostatic chuck.

FIGS. 2A and 2B are diagrams for explaining the basic operation principle of the semiconductor wafer holding device according to the present invention, wherein FIG. 2A is a plan view of the hybrid holding device, FIG.
FIG. 3 is a sectional view showing a detailed structure of a thin electrostatic chuck.

FIG. 3 shows a second embodiment of the semiconductor wafer holding device according to the present invention.
FIGS. 3A and 3B show an embodiment of the present invention, wherein FIG.
(B) is a front view.

4A and 4B are diagrams for explaining a state where a semiconductor wafer is held by an electrostatic chuck, wherein FIG. 4A is a cross-sectional view of the semiconductor wafer, and FIG. 4B is a diagram when the semiconductor wafer is held on the electrostatic chuck; It is sectional drawing which shows the state of.

5A and 5B are views for explaining a state of holding a semiconductor wafer by a conventionally known three-point support method, in which FIG. 5A is a plan view and FIG. 5B is a cross-sectional view.

6A and 6B are views for explaining a holding state of a semiconductor wafer by a conventionally known clamping method, wherein FIG. 6A is a plan view and FIG. 6B is a cross-sectional view taken along line AA ′ of FIG. .

FIG. 7 is a diagram illustrating a holding state of a semiconductor wafer by a hybrid method that has been already proposed in the past;
(A) is a plan view and (b) is a cross-sectional view.

[Explanation of symbols]

Reference Signs List 1 thin electrostatic chuck, 1a insulating layer, 1b adhesive layer, 1c electrode layer, 1d adhesive layer, 1e insulating layer, 2
... Semiconductor wafer, 3 ... Support projection, 4 ... Stage, 5 ... High voltage DC power supply, 6 ... Clamp, 7 ... Rubber pad, 8 ... Insulating spacer, 9 ... Leaf spring.

Claims (4)

[Claims] 1. A stage having at least three support protrusions for restraining a semiconductor wafer in a direction perpendicular to a wafer surface, and a thin electrostatic chuck elastically deformable in a direction perpendicular to the wafer surface of the semiconductor wafer. The holding device for a semiconductor wafer, wherein the thin electrostatic chuck is formed using an organic elastic material. 2. The semiconductor wafer holding device according to claim 1, wherein said thin electrostatic chuck is formed of an organic elastic material sheet having high electric resistance and high thermal conductivity, and an organic elastic material sheet having low electric resistance and high thermal conductivity. Comprising an organic elastic material sheet having properties,
A semiconductor wafer holding device formed by laminating and adhering these sheets. 3. The semiconductor wafer holding device according to claim 2, wherein a silicon rubber is used as a base material of the organic elastic material sheet, and a base material of an adhesive used for laminating and bonding the sheets. A semiconductor wafer holding device, characterized by using silicon rubber. 4. The device for holding a semiconductor wafer according to claim 2, wherein the thin electrostatic chuck is formed in the organic elastic material sheet with a slit opened at one edge, thereby forming the wafer surface. A semiconductor wafer holding device formed so as to be elastically deformable in a vertical direction.