KR101594987B1 - Bipolar electrostatic chuck and manufacturing method thereof - Google Patents

Bipolar electrostatic chuck and manufacturing method thereof Download PDF

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Publication number
KR101594987B1
KR101594987B1 KR1020140141484A KR20140141484A KR101594987B1 KR 101594987 B1 KR101594987 B1 KR 101594987B1 KR 1020140141484 A KR1020140141484 A KR 1020140141484A KR 20140141484 A KR20140141484 A KR 20140141484A KR 101594987 B1 KR101594987 B1 KR 101594987B1
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South Korea
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pattern
electrode
insulating layer
electrode pattern
electrostatic chuck
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KR1020140141484A
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Korean (ko)
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심재은
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심재은
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
    • H01L21/683—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for supporting or gripping
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
    • H01L21/683—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for supporting or gripping
    • H01L21/6831—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for supporting or gripping using electrostatic chucks
    • H01L21/6833—Details of electrostatic chucks

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Manufacturing & Machinery (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Container, Conveyance, Adherence, Positioning, Of Wafer (AREA)

Abstract

The present invention relates to a bipolar electrostatic chuck used for semiconductor fabrication equipment and a fabricating method thereof. The bipolar electrostatic chuck includes: a metal support that has an incised pattern corresponding to an electrode pattern; an insulating layer that is mounted on the top surface of the metal support and has the same surface pattern as the incised pattern; and an electrode material that is mounted on the top surface of the insulating layer and fills groove parts of the surface pattern. The electrode material that fills the groove parts of the surface pattern makes up the electrode pattern. Meanwhile, the fabricating method of the bipolar electrostatic chuck comprises: forming, on the top surface of the metal support, the incised pattern corresponding to the electrode pattern of the metal support; forming the insulating layer on the top surface of the metal support; forming the electrode material on the top surface of the insulating layer; and forming the electrode pattern, wherein the electrode pattern is formed by removing the protruded electrode material, thereby exposing the insulating layer while a protective layer may be formed on the electrode pattern and the exposed insulating layer. The bipolar electrostatic chuck according to the present invention is fabricated when the electrode pattern is formed by line-cutting the metal support to produce the incised pattern corresponding to the electrode pattern, coating and hardening the electrode material and partially removing the electrode material. Accordingly, the present invention is capable of achieving a high degree of adhesion by precisely adjusting the clearance between the electrodes of the electrode pattern and increasing yield rates by controlling the interference or short circuits between the electrode patterns.

Description

TECHNICAL FIELD [0001] The present invention relates to a bipolar electrostatic chuck,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic chuck used in a semiconductor manufacturing apparatus and a manufacturing method thereof, and more particularly to a bipolar electrostatic chuck for attracting an object to be inspected such as a wafer or a substrate by applying a voltage to a bipolar electrode pattern .

Generally, it is important to improve the positioning accuracy by adsorbing and fixing the wafer or the substrate at a predetermined position when the circuit is highly integrated or the pattern is finely patterned in the semiconductor manufacturing process.

Conventionally, vacuum chucks or mechanical chucks are known as means for adsorbing and fixing a wafer or a substrate during a semiconductor manufacturing process. However, since the vacuum chuck is processed under vacuum, there is a problem that the adsorption force is weak, there is a problem of substrate deformation due to local adsorption, and a mechanical chuck is complicated and the maintenance is difficult.

Recently, an electrostatic chuck using electrostatic force has been widely adopted as an alternative to the conventional substrate attraction and fixing method. The electrostatic chuck is a bipolar electrostatic chuck having a unipolar electrostatic chuck having one electrode itself and two electrodes.

The bipolar electrostatic chuck comprises a support such as a metal, an interdigitated electrode pattern formed by alternately patterning positive and negative electrodes formed on the upper surface of the support, and an insulating layer formed thereon, When a voltage is applied to the electrode pattern in a state in which an object to be adsorbed such as a substrate is placed on the insulating layer, Coulomb's force acts in such a manner that the object attracts the object. These bipolar electrostatic chucks are widely used in large-area substrate processing because they have a relatively strong attraction force at low voltage compared to unipolar electrostatic chucks.

FIG. 1 is a schematic diagram illustrating a manufacturing method of a bipolar electrostatic chuck according to a conventional method. Referring to FIG. 1, an insulating layer 120 is formed on an upper surface of a metal support 110, ) Is cured by screen printing. This method is advantageous in simplifying the process of attaching the sheet form in addition to the coating method in forming the insulating layer 120. However, since the electrode pattern formation is performed by the screen printing method, It is difficult to finely control the width and different kinds of electrodes are interfered with each other or short-circuited during the screen printing process, thereby causing defective products.

On the other hand, since the spacing width of the electrode pattern of the bipolar electrostatic chuck is advantageous as the size is small as a factor of influencing the attraction force, the gap between the electrodes of the electrode pattern is narrowly narrowed and a new method The request is still in existence.

It is an object of the present invention to solve the problems of the prior art described above, and it is an object of the present invention to provide a new bipolar electrostatic chuck capable of finely controlling a distance between electrodes of an electrode pattern and suppressing interference or short- And a manufacturing method thereof.

The gist of the present invention relating to the recognition of the above-mentioned problems and the solution means based on them is as follows.

(1) forming an engraved pattern corresponding to the electrode pattern on the upper surface of the metal support; Forming an insulating layer on an upper surface of the metal support; Forming an electrode material on an upper surface of the insulating layer; And forming the electrode pattern, wherein the formation of the electrode pattern is performed by removing the protruded electrode material to expose the insulating layer.

(2) The method of manufacturing a bipolar electrostatic chuck according to the above (1), wherein the formation of the engraved pattern on the metal support is a mechanical processing method.

(3) The method of manufacturing a bipolar electrostatic chuck according to (1), wherein the insulating layer is formed by coating.

(4) The method of manufacturing a bipolar electrostatic chuck according to (1), wherein the electrode material is formed by coating.

(5) The method of manufacturing a bipolar electrostatic chuck according to (1), wherein the removal of the electrode material is a polishing method.

(6) The method of manufacturing a bipolar electrostatic chuck according to (1), further comprising forming a protective layer on the electrode pattern and the exposed insulating layer.

(7) a metal support provided with an engraved pattern corresponding to the electrode pattern; An insulating layer formed on an upper surface of the metal support and having the same surface pattern as the engraved pattern; And an electrode material formed on the upper surface of the insulating layer and filled in the groove of the surface pattern, wherein the electrode pattern is constituted by the electrode material filled in the groove portion of the surface pattern.

(8) The bipolar electrostatic chuck according to (7), further comprising a protective layer formed on the electrode pattern and the exposed insulating layer.

The bipolar electrostatic chuck according to the present invention is manufactured in such a manner that an engraved pattern corresponding to an electrode pattern is line-machined on a metal support, a coating material is coated and cured, and then a part of the electrode material is removed to form an electrode pattern, The strong attraction force can be realized and the interference or short circuit between the electrode patterns can be suppressed and the product yield can be improved.

1 is a schematic diagram of a process for manufacturing a bipolar electrostatic chuck according to a conventional method.
2 is a structural view of a bipolar electrostatic chuck according to the present invention.
3 is a photograph of an electrode pattern of a bipolar electrostatic chuck according to an embodiment of the present invention.
4 is a schematic diagram of a process for manufacturing a bipolar electrostatic chuck according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same or similar reference numerals are given to the same or similar parts.

Also, throughout the specification, when an element is referred to as including an element, it is to be understood that the element may include other elements, without departing from the spirit or scope of the present invention.

It is also to be understood that when an element is "provided" optionally, provided, or included, it means that it may not be an essential component for solving the present invention, but may be arbitrarily adopted in connection with such a solution do.

First, the structure of the bipolar electrostatic chuck 20 according to the present invention will be described. FIG. 2 is a cross-sectional view of a bipolar electrostatic chuck according to the present invention, and FIG. 4 is a schematic view of a process for manufacturing a bipolar electrostatic chuck according to the present invention.

Referring to FIG. 2, the bipolar electrostatic chuck 20 basically includes a metal support 210, an insulating layer 220, and an electrode pattern 230.

The upper surface of the metal support 210 is provided with an engraved pattern corresponding to the electrode pattern 230. The engraved pattern can be formed in a manner such that the width A of the electrode pattern 230 in the manufacturing process of the bipolar electrostatic chuck The metal support 210 is formed before the electrode pattern 230 is formed.

The metal support body 210 constitutes the body of the bipolar electrostatic chuck 20 to support the adsorbent and a channel for cooling the heat transferred during the semiconductor manufacturing process and a passage for uniformly supplying the cooling gas (Not shown), and the planar shape may be embodied in a circular shape (see FIG. 2) or other shapes similar to the shape of the respiratory complex such as the substrate.

The properties required for the metal support should be resistance to exposed heat during the process, and the heat-induced deformation force when dissimilarly bonded to the ceramic is similar to that of the ceramic, so that there is no warpage after adhesion or coating. It should also be a material with a high heat transfer rate for the function of heat transfer for cooling. Aluminum has a melting point of 933.14 k and a coefficient of thermal expansion of 23.1 ㎛ · m -1 · K -1 and a thermal conductivity of 300 K 237 W / (m · K). Copper may also be used as the material of the metal support and may be used when it is necessary to shut off sources other than copper due to process conditions. The copper has a melting point of 1357.77 K, a thermal expansion coefficient of 25.5 · m -1 K -1 and a thermal conductivity of (300 K) 401 W / (m K).

The insulating layer 220 electrically isolates the metal support 210 from the electrodes branched into the positive electrode and the negative electrode while receiving the electrode pattern 230, thereby forming the electrostatic chuck 20 according to the leakage current. To prevent the loss of function.

As the material of the insulating layer 220, materials such as alumina, yttria (Y 2 O 3 ), aluminum nitride (AlN), and zirconium oxide (ZrO 2) may be used. In this case, the thickness of the insulation layer satisfies a minimum thickness for electrical insulation between the electrode pattern 230 and the metal support 210, and is 0.2 to 0.5 mm in order to smoothly form the internal electrode pattern 230 and maintain the dielectric constant. .

Referring to FIG. 3, the electrode pattern 230 is patterned into a positive electrode and a negative electrode branched from a positive electrode break point and a negative electrode break point, as in a general bipolar electrostatic chuck, The positive charge is generated on one side and the negative charge is generated on the other side, and a coulomb force acts between these charges, thereby operating in such a manner as to adsorb an adsorbent such as a substrate.

2, the electrode pattern 230 corresponds to an engraved pattern of the metal substrate 210 and is filled and accommodated in a surface pattern of the insulating layer 220 corresponding to the engraved pattern.

The electrode pattern 230 may be formed of aluminum titanium oxide (AlTiOx) tungsten / copper material. The electrode pattern 230 may be formed with a minimum attractive force due to an electrical force applied to the bipolar electrode, . For this purpose, it is preferable that the distance between the electrodes of the electrode pattern 230 is controlled to 1 cm or less. Further, according to the present invention, The present invention can realize a fine electrode-to-electrode spacing width, thereby realizing an attraction force for a substrate such as a wafer of a larger size.

Alternatively, the protective layer 240 may be formed on the electrode pattern 230 and the insulating layer 220 exposed to the outside. For reference, in FIG. 3, the protective layer is omitted for the purpose of showing the shape of the electrode pattern in the protective layer. The protective layer 230 protects the electrode pattern 230 and functions as an insulation between the electrodes of the electrode pattern 230.

Materials such as alumina, yttria (Y 2 O 3 ), aluminum nitride (AlN), and zirconium oxide (ZrO 2) may be used as the material of the protective layer 240. In this case, the thickness of the protective layer 240 is preferably 0.2 to 0.5 mm so as to be suitable for performing the function of insulation and protection against the electrode pattern 230.

Next, a method of manufacturing a bipolar electrostatic chuck according to the present invention will be described. 4 is a process schematic diagram of a bipolar electrostatic chuck manufacturing method according to the present invention.

First, intaglio patterns 210a and 210b corresponding to the electrode pattern are formed on the plate-like metal support 210 (Fig. 4 (a)). The present invention is basically characterized in that the engraved patterns 210a and 210b are linearly machined on the metal support 210 in order to narrow the distance between the electrodes of the bipolar electrostatic chuck.

Specifically, in the engraved patterns 210a and 210b, the width of the concave portion corresponds to a region where the electrode pattern is formed on the concave portion 210a, and the width of the concave portion 210b determines the width of the convex portion 210b The width of the electrode pattern determines the distance between the electrodes.

The formation of the engraved patterns 210a and 210b is not particularly limited and can be suitably selected in consideration of realistic machining cost and required machining accuracy. For example, the machining method of the metal support 210 can be machined into a large lathe for circular machining of the body, and machining of the engraved patterns 210a and 210b and machining of the inner cooling passages (not shown) Lt; / RTI >

Next, the insulating layer 220 is formed on the upper surface of the metal supporting body 210 on which the engraved patterns 210a and 210b are formed (FIG. 4B). The insulating layer 220 is formed to have a uniform thickness and thus has surface patterns 220a and 220b having the same shape as the concavo-convex shape of the engraved patterns 210a and 210b of the metal support 210.

The method of forming the insulating layer 220 is not particularly limited, but it is preferable that the insulating layer 220 is formed by a coating method that covers each electrode for independence of each electrode of the electrode pattern 230. In addition, since the insulating layer 230 such as a ceramic formed through the coating method does not require a separate sintering process, it is possible to form the insulating layer 230 directly on the metal support 210. The coating method is carried out in such a manner that, for example, fine particles (less than or equal to 2) of ceramic powder are injected through a high-pressure device and each particle is entangled. In this case, as ceramic particles are injected with small force and strong pressure, So that it has an excellent function as the insulating layer 230.

Next, the electrode material 230 is formed on the upper surface of the insulating layer 220 having the surface patterns 220a and 220b (FIG. 4C). The electrode material 230 is formed to have a uniform thickness so that the concavo-convex shape of the engraved patterns 210a and 210b of the metal support 210 and the same surface as the surface patterns 220a and 220b of the insulating layer 220 Patterns 230a and 230b are provided.

The method of forming the electrode material 230 is not particularly limited, but may be formed in the same manner as the method of forming the insulating layer 230 described above.

Subsequently, the electrode material 230 is patterned into an interdigitated electrode pattern in which a positive electrode and a negative electrode are alternately patterned. The formation of the electrode pattern is performed by removing the protruded portion 230b of the electrode material 230.

The method of removing the outwardly projecting electrode material portion 230b is preferably to mechanically polish the portion 230b. This mechanical polishing is carried out until a portion of the insulating layer 230 is exposed to the outside by completely removing the protruding electrode material portion 230b.

Specifically, such mechanical polishing is used for milling, and the surface is polished by Polishing M / C and Lapping to finely adjust the surface roughness required for the contact surface with the substrate such as the wafer to be adsorbed. Surface polishing accompanied by electrode formation and coating processes is the main process that determines the function of the electrostatic chuck. The surface roughness value should be kept below 5 μm. If the surface roughness value is high, It becomes difficult to uniformly charge the chuck.

Subsequently, a protective layer 240 may be optionally formed over the patterned electrode material 230 and the exposed insulating layer 230 (FIG. 4 (e)). This protective layer 240 may be selected from the same material as the insulating layer 230 and coated in the same manner.

As described above, the bipolar electrostatic chuck 20 according to the present invention differs from the conventional method in which the electrode pattern is formed by simply screen-printing, and the engraved patterns 210a and 210b corresponding to the electrode pattern are formed on the metal support 210, The electrode material 230 is coated and cured, and then the part 230b is removed to form an electrode pattern. Thus, it is possible to finely control the distance between electrodes of the electrode pattern. In addition, this method can effectively improve the product yield by effectively suppressing interference or short-circuiting between the electrode patterns, which is a problem of the conventional screen printing method.

While the foregoing is directed to a specific embodiment of the present invention, it is to be understood that the above-described embodiment of the present invention has been disclosed for the purpose of illustration and is not to be construed as limiting the scope of the present invention, It should be understood that various changes and modifications may be made to the disclosed embodiments without departing from the spirit of the invention.

For example, as described above, a method of forming an engraved pattern on the metal support 210, a method of forming an insulating layer, an electrode material and a protective layer, and a method of forming an electrode pattern by removing a part of the electrode material It is also possible to configure the apparatus in various ways at the level of the skilled person in view of the working environment and the specifications required for the product in addition to the method exemplified by the embodiments.

It is therefore to be understood that all such modifications and alterations are intended to fall within the scope of the invention as disclosed in the following claims or their equivalents.

20: bipolar electrostatic chuck 210: metal support
220: insulating layer 230: electrode pattern
240: protective layer

Claims (8)

Forming an engraved pattern corresponding to the electrode pattern on the upper surface of the metal support; Forming an insulating layer on an upper surface of the metal support; Forming an electrode material on an upper surface of the insulating layer; And forming the electrode pattern,
Wherein the formation of the electrode pattern is performed by removing the protruding electrode material to expose the insulating layer.
The method according to claim 1, wherein the formation of the engraved pattern on the metal support is a mechanical processing method.
The method of claim 1, wherein the insulating layer is formed by a coating method.
The method for manufacturing a bipolar electrostatic chuck according to claim 1, wherein the electrode material is formed by coating.
The bipolar electrostatic chuck manufacturing method according to claim 1, wherein the removal of the electrode material is a polishing process.
The method of claim 1, further comprising forming a protective layer over the electrode pattern and the exposed insulating layer.
A metal support having an engraved pattern corresponding to the electrode pattern; An insulating layer formed on an upper surface of the metal support and having the same surface pattern as the engraved pattern; And an electrode material formed on an upper surface of the insulating layer and filled in a groove portion of the surface pattern,
Wherein the electrode pattern is constituted by the electrode material filled in the groove portion of the surface pattern.
The bipolar electrostatic chuck according to claim 7, further comprising a protective layer formed on the electrode pattern and the exposed insulating layer.
KR1020140141484A 2014-10-20 2014-10-20 Bipolar electrostatic chuck and manufacturing method thereof KR101594987B1 (en)

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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08507196A (en) * 1994-01-31 1996-07-30 アプライド マテリアルズ インコーポレイテッド Electrostatic chuck with conformal insulator film
JP2000228441A (en) * 1999-01-13 2000-08-15 Applied Materials Inc Improved temperature control, electrostatic chuck and the same with breakdown resistance
JP2003340648A (en) * 2002-05-20 2003-12-02 Koyo Seiko Co Ltd Electrochemical machining electrode and dynamic pressure bearing manufactured using the electrode
JP2008112763A (en) * 2006-10-27 2008-05-15 Tomoegawa Paper Co Ltd Electrostatic chuck

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08507196A (en) * 1994-01-31 1996-07-30 アプライド マテリアルズ インコーポレイテッド Electrostatic chuck with conformal insulator film
JP2000228441A (en) * 1999-01-13 2000-08-15 Applied Materials Inc Improved temperature control, electrostatic chuck and the same with breakdown resistance
JP2003340648A (en) * 2002-05-20 2003-12-02 Koyo Seiko Co Ltd Electrochemical machining electrode and dynamic pressure bearing manufactured using the electrode
JP2008112763A (en) * 2006-10-27 2008-05-15 Tomoegawa Paper Co Ltd Electrostatic chuck

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