JP4021661B2 - Electrostatic chuck device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention also relates wafer or the like of the conductor or semi-conductive, such as LCD glass substrate to the electrostatic chuck equipment for adsorbing fixed by electrostatic force.
[0002]
[Prior art]
In the process of processing a semiconductor wafer, a chuck device is used to fix the wafer to a predetermined part of a processing machine such as a plasma etching apparatus. There are mechanical, vacuum, and electrostatic devices as the chuck device. Among these, the electrostatic chuck device has an advantage that it is easy to handle and can be used in a vacuum.
[0003]
As a conventional electrostatic chuck device, for example, one having a structure as shown below can be cited.
FIG. 11 is a cross-sectional view of a conventional electrostatic chuck device. The electrostatic chuck device 1 includes a substrate 5 having a through hole 2 opened at the center of both surfaces, insulating layers 6 and 7 and sandwiched between them. An electrode sheet 9 laminated on the substrate 5, a lead wire 24 connecting the exposed portion of the conductive layer 8 of the electrode sheet 9 and the DC high-voltage power supply 23, and a lower peripheral edge of the substrate 5 And a base support frame 16 to which the base 5 is attached by a bolt 15 and an insulating adhesive 14 for sealing the through hole 2 of the base 5.
[0004]
In this electrostatic chuck device 1, an electrostatic force is generated on the upper surface of the electrode sheet 9 by energizing the electrode sheet 9 from the DC high-voltage power supply 23 via the lead wire 24, and the upper surface of the electrode sheet 9 is generated by the electrostatic force. A wafer (not shown) is fixed by suction.
[0005]
[Problems to be solved by the invention]
In the electrostatic chuck device 1, when the electrode sheet 9 is deteriorated by plasma or the like during wafer processing, the electrode sheet 9 needs to be replaced. In the replacement work of the electrode sheet 9, the electrode sheet 9, the lead wire 24 and the insulating adhesive 14 are peeled off from the substrate 5, and then the electrode sheet 9 in which the lead wire 24 is connected to the conductive layer 8 by soldering. It was necessary to attach the lead wire 24 to the upper surface of the substrate 5 while inserting the lead wire 24 through the through hole 2 and seal the through hole 2 with the insulating adhesive 14.
[0006]
Thus, in the work of replacing the electrode sheet 9, the insulating adhesive 14 in the through hole 2 had to be completely removed. Since the insulating adhesive 14 is filled in the narrow through hole 2, labor and time are required for the removal work, and workability is poor. Further, the lead wire 24 is damaged during the operation of removing the insulating adhesive 14, and the lead wire 24 cannot be reused.
[0007]
By the way, in recent years, in the manufacture of liquid crystal, electrostatic chuck devices have been used to fix a glass substrate to a predetermined part of a processing machine in a process of processing a glass substrate for liquid crystal. This glass substrate is large and has a size of 650 mm × 550 mm, and the base of the electrostatic chuck device is enlarged in accordance with this size.
[0008]
Therefore, a large electrode sheet is required to electrostatically adsorb a large glass substrate, but there is a problem that conventional electrode sheet manufacturing equipment cannot be used for manufacturing a large electrode sheet. For this purpose, two or more conventional electrode sheets are used, and these are attached on a large substrate to cope with adsorption of a large glass substrate. When the electrode sheet is divided into two or more, it is necessary to increase the number of through holes for supplying power to the electrode sheet according to the number of electrode sheets.
[0009]
Therefore, in a large electrostatic chuck device corresponding to such a glass substrate for liquid crystal, the electrode sheet repositioning operation must be performed on each electrode sheet, which has a problem in workability. It was.
[0010]
Accordingly, an object of the present invention is to provide an electrostatic chucking device which can easily perform bonding replacement of electrodes sheets.
[0011]
[Means for Solving the Problems]
The electrostatic chuck device of the present invention has a substrate having a through hole, at least an insulating layer and a conductive layer sandwiched between the plurality of electrode sheets stacked on the substrate upper surface, and is attached to and detached from the substrate lower surface. An electrostatic chuck device comprising an electrostatic chuck device power supply connector attached in a possible manner, wherein the electrostatic chuck device power supply connector includes a connector main body having a plurality of holes opened upward, and these comprising a feed pin which is arranged in the hole, and a spring to push the feeding pin upwardly, to the electrode sheet feeding portion is formed on the end portion of the power feeding portion, the exposed portion of the conductive layer is formed, the conductive layer of the exposed portion of the feeding portion of the electrode sheet, in contact with the tip portion of the feed pin of the electrostatic chucking device for feeding connector comes, the insulating portion surrounding the tip of the feed pin projecting from the feeder connector top There, characterized in that provided between the power supply connector top and base lower surface.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail.
FIG. 1 is a side sectional view showing an example of the electrostatic chuck device of the present invention.
The electrostatic chuck device 30 includes a base 32 in which a connector fitting recess 31 is formed in the center of the lower surface and a through hole 2 penetrating from the center of the upper surface to the connector fitting recess 31; the insulating layers 6 and 7; The electrode sheet 9 having a conductive layer 8 sandwiched between them and laminated on the substrate 32, and a part of the electrode sheet 9 are processed into a tongue shape, and the exposed portion 12 of the conductive layer 8 is formed at the end thereof. The formed power supply unit 13, the base support frame 16 that supports the lower peripheral edge of the base 32, the base 32 is attached by the bolt 15, and the connector fitting recess 31 on the bottom of the base 32 are detachably attached by the bolt 34. The electrostatic chuck device power supply connector 40 is generally configured.
Further, a gap 36 sealed with a seal member 35 (O-ring or the like) is formed between the substrate 32 and the electrostatic chuck device power supply connector 40.
[0015]
As shown in the enlarged cross-sectional view of the main part of FIG. 2, the electrostatic chuck device power supply connector 40 is a connector in which a small-diameter pin hole 41 opened upward and a large-diameter power supply hole 42 communicating with the pin hole 41 are formed. A main body 43, a cup 44 inserted in the power supply hole 42 so as to close the opening of the power supply hole 42, a power supply pin 45 disposed in the cup 44, and one end thereof in contact with the terminal portion 46 of the power supply pin 45; A spring 48 is disposed in the cup 44 with the other end in contact with the bottom of the cup 44 and pushes the power supply pin 45 upward so that the tip 47 of the power supply pin 45 protrudes from the pin hole 41 on the upper surface of the connector body 43. And is roughly configured.
Further, a lead wire 24 extending from the DC high-voltage power supply 23 and led into the cup 44 through the hole 49 at the bottom of the cup 44 is connected to the spring 48 by solder or the like. The cup 44 and the lead wire 24 are It is fixed to the connector main body 43 and the cup 44 by an adhesive 50, respectively. Here, the connection position of the lead wire 24 to the spring 48 is preferably the lower part of the spring 48 so as not to hinder the movement of the power feed pin 45.
[0016]
The connector main body 43 is a member having a convex cross section, and an insertion hole is formed on the periphery thereof. The electrostatic chuck device power supply connector 40 is detachably attached to the lower surface of the substrate 32 by passing the bolts 34 through the insertion holes and screwing the bolts 34 into the bolt holes on the lower surface of the substrate 32.
The material of the connector main body 43 is not particularly limited, and examples thereof include plastic and ceramic. Among these, plastic is preferably used because it is lightweight and facilitates attachment / detachment of the power supply connector 40 for the electrostatic chuck device and is easy to process. Examples of such plastic include polyphenylene sulfide (PPS), polyether ether ketone (PEEK), polyamide, polyester, acrylic resin, polybutylene terephthalate (PBT), and polyether sulfone.
[0017]
The cup 44 holds the power supply pin 45 and the spring 48 in the power supply hole 42.
The material of the cup 44 is not particularly limited, and examples thereof include plastic and ceramics. Of these, plastic is preferably used from the viewpoint of processability and insulation. Examples of such plastic include polyphenylene sulfide (PPS), polyether ether ketone (PEEK), polyamide, polyester, acrylic resin, polybutylene terephthalate (PBT), and polyether sulfone.
[0018]
The power supply pin 45 includes a cylindrical rod-shaped pin main body and a disk-shaped terminal end portion 46 attached near the end of the main body. The terminal end portion 46 includes a small-diameter pin hole 41 and a large-diameter power supply hole 42. The power supply pin 45 is prevented from coming off by contacting the step formed by the difference in diameter.
The material of the power feed pin 45 is not particularly limited as long as it is made of a conductive material. Examples of the conductive material include copper, copper alloy, iron, aluminum, stainless steel, silver, and gold.
[0019]
The material and shape of the spring 48 are not particularly limited as long as it is made of metal and has spring elasticity.
The adhesive 50 fixes the cup 44 and the lead wire 24 to the connector main body 43 and the cup 44, respectively, and seals the opening of the power supply hole 42 so that the base 32 and the power supply connector 40 for the electrostatic chuck device are interposed. The gap 36 formed in the above is hermetically sealed. Therefore, the adhesive 50 is used so as to completely cover the opening of the power supply hole 42.
Examples of the adhesive 50 include epoxy resin, phenol resin, butadiene-acrylonitrile copolymer, olefin copolymer, polyphenyl ether copolymer, polyester resin, polyimide resin, polyamide resin, and silicone resin.
[0020]
As the substrate 32, a known material generally used in an electrostatic chuck device can be used. Examples of the material include metals and ceramics.
The base support frame 16 supports the base 32 and fixes the electrostatic chuck device 30 in the processing machine. A space inside the base support frame 16 is wide to facilitate attachment / detachment of the power supply connector 40 for the electrostatic chuck device. It is desirable that
[0021]
The insulating layers 6 and 7 of the electrode sheet 9 are preferably insulating films or ceramics having a heat resistant temperature of 150 ° C. or higher in consideration of electrical characteristics such as dielectric constant ε and withstand voltage. Examples of the insulating film having heat resistance of 150 ° C. or higher include fluororesin (fluoroethylene-propylene copolymer, etc.), polyether sulfone, polyether ether ketone, cellulose triacetate, silicone rubber, polyimide, and the like. .
[0022]
Further, when the insulating layers 6 and 7 are made of ceramics, they are less likely to be worn or deformed, are not easily damaged, have good plasma resistance and etching resistance, have extremely high durability, and are easy to handle. Are better. Moreover, the lifetime of an electrostatic chuck apparatus becomes long by comprising the insulating layers 6 and 7 with ceramics.
Although the thickness of the insulating layers 6 and 7 is not specifically limited, The range of 100-1000 micrometers is preferable and 100-500 micrometers is more preferable. The thinner one is preferable from the viewpoint of thermal conductivity, but 200 to 300 μm is particularly preferable in view of mechanical strength, withstand voltage and durability (fatigue resistance).
[0023]
The conductive layer 8 of the electrode sheet 9 is a layer made of a conductive material. As the conductive material, a copper foil having a thickness of 50 μm or less is usually used. In addition, metal foils such as nickel, chromium, iron, aluminum, stainless steel, and tin may be used.
Further, the conductive layer 8 may be formed by vapor deposition or sputtering. For example, nickel, chromium, aluminum or the like is preferable for forming by vapor deposition or sputtering, and copper, chromium or the like is preferable for forming by plating. Besides these, tin, silver, palladium, etc. and alloys thereof may be used. In particular, silver, platinum, palladium, molybdenum, magnesium, tungsten, and alloys thereof can be handled in a paste or powder form, so that they are excellent in workability and printability, and among them, a palladium alloy has good conductivity and workability. .
0.1-10 micrometers is preferable and, as for the thickness of the conductive layer 8, 0.5-8 micrometers is more preferable. When the film thickness is less than 0.1 μm, it is difficult to form a uniform film, and in the case of a highly reactive material such as aluminum, it is difficult to maintain stable conductivity because it is easily oxidized. On the other hand, if it exceeds 10 μm, the deposition cost is high in the vapor deposition or plating method.
[0024]
The electrode sheet 9 is usually bonded and laminated on the metal substrate 5 via an adhesive layer (not shown).
The adhesive for the adhesive layer is not particularly limited as long as it has high adhesiveness and heat resistance, and is preferably a thermosetting resin in terms of ensuring high heat resistance. The thickness of the adhesive layer is not limited, but in order to increase the thermal conductivity, it is better to be thin, preferably 5 to 100 μm, more preferably 5 to 50 μm, still more preferably 5 to 30 μm, and about 10 μm is preferred.
[0025]
As shown in FIG. 3, the electrode sheet 9 is provided with a feeding portion 13 having a U-shaped cut at the center and a tongue-like portion surrounded by the cut hanging downward. An exposed portion 12 of the conductive layer 8 is formed at the end. As shown in FIG. 4, the power feeding portion 13 of the electrode sheet 9 is affixed to the through hole 2 and the connector fitting recess 31 with its end bent into an L shape.
[0026]
Next, the operation of replacing the electrode sheet in the electrostatic chuck device 30 will be described.
First, the electrostatic chuck device power supply connector 40 is removed from the substrate 32 by removing the bolt 34 that fixes the electrostatic chuck device power supply connector 40 to the lower surface of the substrate 32.
Next, the electrode sheet 9 is peeled off from the upper surface of the substrate 32 while removing the power feeding part 13 from the through hole 2.
[0027]
After peeling off the electrode sheet 9 from the base 32, a new electrode sheet 9 is attached to the upper surface of the base 32 with an adhesive while inserting the power feeding part 13 into the through hole 2, and the power feeding part 13 is attached to the inner wall surface of the through hole 2 and Affixed to the connector fitting recess 31.
Next, the electrostatic chuck device power supply connector 40 is attached to the lower surface of the substrate 32 with bolts 34.
[0028]
In such an electrostatic chuck device 30, the tip end portion of the power feed pin 45 of the power feed connector 40 for the electrostatic chuck device that is detachably attached to the lower surface of the base 32 on the exposed portion 12 of the power feed portion 13 of the electrode sheet 9. 47 is brought into contact with each other so that the conductive layer 8 of the electrode sheet 9 and the lead wire 24 are electrically connected, so that the lead wire is directly connected to the conductive layer 8 of the electrode sheet 9 as in the conventional electrostatic chuck device. It is not necessary to solder 24 and fill the through hole 2 with an insulating adhesive. As a result, the electrode sheet 9 can be removed simply by removing the power supply connector 40 for the electrostatic chuck device, and the work for removing the insulating adhesive is not required, so that the electrode sheet 9 can be easily replaced. .
[0029]
Further, in such an electrostatic chuck device 30, the power supply pin 45 pushed upward by the spring 48 is brought into contact with the exposed portion 12 of the power supply unit 13, and the electrode is supplied from the DC high-voltage power supply 23 connected to the spring 48. By energizing the sheet 9, an electrostatic force is generated on the upper surface of the electrode sheet 9, and the wafer or the glass substrate can be adsorbed and fixed on the upper surface of the electrode sheet 9 by the electrostatic force.
[0030]
Note that the electrostatic chuck device of the present invention is not limited to the above example, and when adsorbing a large glass substrate for liquid crystal, the electrode sheet 9 as shown in FIG. A plurality of them may be provided.
FIG. 6 is a cross-sectional view of a main part of the electrostatic chuck device 51 of FIG. 5. The electrostatic chuck device 51 has a plurality of through holes 2 formed in the base 52 and a plurality of electrode sheets 9 on the base 52. The power feeding portions 13 of the electrode sheet 9 are bonded to each other from the surface of the base plate 52 through the through holes 2 to the connector fitting concave portion 31, and a plurality of power feeding pins 45 are attached to the connector fitting concave portion 31 on the bottom surface of the base plate 52. An electrostatic chuck device power supply connector 60 having a detachable attachment is attached by a bolt 34.
Here, as shown in FIG. 7, the electrode sheet 9 has a tongue-shaped power feeding portion 13 formed on the side edge portion, and an exposed portion 12 of the conductive layer 8 is formed at the end of the power feeding portion 13. Yes. As shown in FIG. 8, the power feeding portion 13 of the electrode sheet 9 is affixed to the through hole 2 and the connector fitting recess 31 with its end bent into an L shape.
[0031]
Further, as shown in FIG. 9, the upper surface of the connector body 63 is provided with an insulating member 61 that surrounds the periphery of the tip portion 47 of the power supply pin 45 to prevent discharge between the power supply pins 45 and to prevent the electrode sheet from being discharged. 9 is configured to prevent damage.
As shown in FIG. 10, the insulating member 61 is a columnar member provided with a pin hole 62 in the center, and the material thereof is not particularly limited as long as it can be electrically insulated. Insulating elastic body (rubber), insulating plastic, ceramics, glass, metal oxide, and the like. Among them, an insulating elastic body that can contact the lower surface of the power supply unit 13 and the upper surface of the connector main body 63 without a gap by elastic deformation is preferable, and silicone rubber is particularly preferable in terms of electrical insulation and heat resistance.
[0032]
In addition, the insulating member in the present invention is not limited to the shape in the illustrated example, and may have any shape as long as the shape surrounds the periphery of the tip portion of the power supply pin. Further, the insulating member may be provided so as to be in contact with the lower surface of the substrate and the upper surface of the connector body when the electrostatic chuck device power supply connector is attached to the lower surface of the substrate. Alternatively, the tip 47 of the power supply pin 45 may be provided in advance on the bottom surface of the base so that the exposed portion 12 of the power supply unit 13 can abut.
[0033]
【The invention's effect】
As described above, the electrostatic chuck equipment of the present invention, the power supply connector which is detachably attached to the lower surface of the base of the electrostatic chuck apparatus, a connector body open pores are formed in the upper, the hole A power supply pin disposed in the hole, and a spring disposed in contact with the terminal end of the power supply pin and pushing the power supply pin upward, and the power supply portion is formed on the electrode sheet. The exposed portion of the conductive layer is formed in the portion, and the tip of the power supply pin of the electrostatic chuck device power supply connector is in contact with the conductive layer of the exposed portion of the power supply portion of the electrode sheet. It can be easily replaced.
[0035]
Even when a power supply connector for an electrostatic chuck device having a plurality of power supply pins is used, if an insulating member surrounding the periphery of the tip of the power supply pin is provided between the upper surface of the power supply connector body and the lower surface of the substrate No discharge is generated between the power supply pins, and power can be stably supplied to the electrode sheet.
[Brief description of the drawings]
FIG. 1 is a side sectional view showing an example of an electrostatic chuck device of the present invention.
FIG. 2 is an enlarged cross-sectional view of a main part showing an example of a power supply connector for an electrostatic chuck device according to the present invention.
FIG. 3 is a perspective view showing an example of an electrode sheet in the present invention.
4 is a cross-sectional view of a principal part showing a state where the electrode sheet of FIG. 3 is attached to a base.
FIG. 5 is a perspective view showing another example of the electrostatic chuck device of the present invention.
6 is a cross-sectional view of a main part taken along line VI-VI in FIG.
FIG. 7 is a perspective view showing another example of an electrode sheet according to the present invention.
FIG. 8 is a cross-sectional view of a principal part showing a state where the electrode sheet of FIG. 7 is attached to a base.
FIG. 9 is an enlarged cross-sectional view showing a main part of another example of the power supply connector for the electrostatic chuck device according to the present invention.
FIG. 10 is a perspective view showing an example of an insulating member in the present invention.
FIG. 11 is a side sectional view showing an example of a conventional electrostatic chuck device.
[Explanation of symbols]
2 Through-hole 6 Insulating layer 7 Insulating layer 8 Conductive layer 9 Electrode sheet 30 Electrostatic chuck device 32 Base 40 Electrostatic chuck device power supply connector 41 Pin hole 42 Power supply hole 43 Connector body 45 Power supply pin 48 Spring 51 Electrostatic chuck device 60 Electrostatic chuck device power supply connector 61 Insulating member 63 Connector body

Claims (1)

An electrostatic chuck device having a base with a through-hole formed therein, at least an insulating layer and a conductive layer sandwiched therebetween, a plurality of electrode sheets stacked on the upper surface of the base, and detachably attached to the lower surface of the base An electrostatic chuck device comprising a power feeding connector for use,
Feeding connector the electrostatic chuck device, comprising: a connector body having a plurality of holes opening upward is formed, a feed pin which are respectively disposed in these holes, and a spring to push the feeding pin upwardly,
The electrode sheet is formed with a power feeding part, and an exposed part of the conductive layer is formed at an end of the power feeding part,
The tip of the power supply pin of the power supply connector for the electrostatic chuck device contacts the conductive layer of the exposed portion of the power supply unit of the electrode sheet ,
An electrostatic chuck device characterized in that an insulating member surrounding the periphery of the tip portion of the power supply pin protruding from the upper surface of the power supply connector is provided between the upper surface of the power supply connector and the lower surface of the substrate .

Images