ELECTROSTATIC CHUCK AND PLASMA PROCESSING APPARATUS
20200161103 ยท 2020-05-21
Inventors
Cpc classification
H01L21/68757
ELECTRICITY
H01J37/20
ELECTRICITY
International classification
H01L21/67
ELECTRICITY
Abstract
The present disclosure provides an electrostatic chuck and a plasma processing apparatus. The electrostatic chuck includes: a base; a heating layer disposed on the base; an insulating layer disposed on the heating layer; and an annular-shaped protection member surrounding an outer peripheral wall of the heating layer and detachably disposed on an outer side of the heating layer. An outer diameter of the heating layer is smaller than both an outer diameter of the base and an outer diameter of the insulating layer. The electrostatic chuck and the plasma processing apparatus provided by the present disclosure not only protects the heating layer during the manufacturing process, but also can be separately replaced when the annular-shaped protection member is damaged. The heating layer is unaffected during the replacement process. Thus, the electrostatic chuck has the characteristics of long lifespan, and low maintenance and replacement cost, etc.
Claims
1. An electrostatic chuck, comprising: a base; a heating layer disposed on the base; an insulating layer disposed on the heating layer; and an annular-shaped protection member surrounding an outer peripheral wall of the heating layer and detachably disposed on an outer side of the heating layer, wherein an outer diameter of the heating layer is shorter than both an outer diameter of the base and an outer diameter of the insulating layer.
2. The electrostatic chuck according to claim 1, wherein: the annular-shaped protection member is elastic; a height of the uncompressed and undeformed annular-shaped protection member in a vertical direction is greater than or equal to a gap between the base and the insulating layer; and when being assembled between the base and the insulating layer, the annular-shaped protection member is capable of blocking the heating layer from a plasma.
3. The electrostatic chuck according to claim 2, wherein: the height of the uncompressed and undeformed annular-shaped protection member in the vertical direction is greater than or equal to the gap between the base and the insulating layer; and when being assembled between the base and the insulating layer, the annular-shaped protection member is compressed and deformed to block the heating layer from the plasma.
4. The electrostatic chuck according to claim 3, wherein: when the annular-shaped protection member is not compressed or deformed, a cross-sectional shape of the annular-shaped protection member in a plane where a central axis of the electrostatic chuck is located is a rectangle, a square, a trapezoid, a circle, or an ellipse.
5. The electrostatic chuck according to claim 4, wherein: when the cross-sectional shape is the rectangle, the square, or the trapezoid, any two adjacent sides of the rectangle, the square, or the trapezoid adopt a rounded corner transition.
6. The electrostatic chuck according to claim 5, wherein: a radius of the rounded corner ranges approximately between 1 mm and 3 mm.
7. The electrostatic chuck according to claim 3, wherein: a cross-sectional shape of the annular-shaped protection member in a plane where a central axis of the electrostatic chuck is located is a circle; and a height of an annular space formed between the outer peripheral wall of the heating layer, an upper surface of the base, and a lower surface of the insulating layer in an axial direction of the electrostatic chuck is smaller than about 90% of a diameter of the cross-sectional shape.
8. The electrostatic chuck according to claim 4, wherein: the cross-sectional shape is the rectangle, the square, or the trapezoid; and an outer annular surface of the annular-shaped protection member is a concave surface.
9. The electrostatic chuck according to claim 8, wherein: a minimum thickness of the annular-shaped protection member in a radial direction is greater than or equal to about 80% of a maximum thickness of the annular-shaped protection member in the radial direction.
10. The electrostatic chuck according to claim 8, wherein: the cross-sectional shape of the concave outer annular surface of the annular-shaped protection member is an arc, a diagonal line, or a folded line; the folded line extends in the vertical direction and includes at least two line segments; any two adjacent line segments of the at least two line segments are connected; and an angle formed between any two adjacent line segments is an acute angle, a right angle, or an obtuse angle.
11. The electrostatic chuck according to claim 1, wherein: the annular-shaped protection member includes an annular-shaped body; the annular-shaped body is disposed between the base and the insulating layer, and surrounds the outer peripheral wall of the heating layer; a height of the uncompressed and undeformed annular-shaped protection member in a vertical direction is greater than or equal to a gap between the base and the insulating layer; at least one annular-shaped extension portion is formed on an outer peripheral wall of the annular-shaped body; when the number of the at least one annular-shaped extension portion is one, the annular-shaped extension portion extends upward on the outer peripheral wall of the annular-shaped body and covers an outer peripheral wall of the insulating layer with a top end of the annular-shaped extension portion not higher than an upper surface of the insulating layer, or extends downward on the outer peripheral wall of the annular-shaped body and covers an outer peripheral wall of the base; and when the number of the at least one annular-shaped extension portion is two, an upper half of the annular-shaped extension portion extends upward on the outer peripheral wall of the annular-shaped body and covers the outer peripheral wall of the insulating layer with the top end thereof not higher than the upper surface of the insulating aye and a lower half of the annular-shaped extension portion extends downward on the outer peripheral wall of the annular-shaped body and covers the outer peripheral wall of the base.
12. The electrostatic chuck according to claim 1, wherein: the annular-shaped protection member is made of a perfluoro rubber.
13. A plasma processing apparatus comprising a processing chamber, wherein: an electrostatic chuck is configured inside the processing chamber; and the electrostatic chuck includes: a base; a heating layer disposed on the base; an insulating layer disposed on the heating layer; and an annular-shaped protection member surrounding an outer peripheral wall of the heating layer and detachably disposed on an outer side of the heating layer, wherein an outer diameter of the heating layer is shorter than both an outer diameter of the base and an outer diameter of the insulating layer.
14. The plasma processing apparatus according to claim 13, wherein: the annular-shaped protection member is elastic; a height of the uncompressed and undeformed annular-shaped protection member in a vertical direction is greater than or equal to a gap between the base and the insulating layer; and when being assembled between the base and the insulating layer, the annular-shaped protection member is capable of blocking the heating layer from a plasma.
15. The plasma processing apparatus according to claim 14, wherein: the height of the uncompressed and undeformed annular-shaped protection member in the vertical direction is greater than or equal to the gap between the base and the insulating layer; and when being assembled between the base and the insulating layer, the annular-shaped protection member is compressed and deformed to block the heating layer from the plasma.
16. The plasma processing apparatus according to claim 15, wherein: when the annular-shaped protection member is not compressed or deformed, a cross-sectional shape of the annular-shaped protection member in a plane where a central axis of the electrostatic chuck is located is a rectangle, a square, a trapezoid, a circle, or an ellipse.
17. The plasma processing apparatus according to claim 16, wherein: when the cross-sectional shape is the rectangle, the square, or the trapezoid, any two adjacent sides of the rectangle, the square, or the trapezoid adopt a rounded corner transition.
18. The plasma processing apparatus according to claim 13, wherein: the annular-shaped protection member includes an annular-shaped body; the annular-shaped body is disposed between the base and the insulating layer, and surrounds the outer peripheral wall of the heating layer; a height of the uncompressed and undeformed annular-shaped protection member in a vertical direction is greater than or equal to a gap between the base and the insulating layer; at least one annular-shaped extension portion is formed on an outer peripheral wall of the annular-shaped body; when the number of the at least one annular-shaped extension portion is one, the annular-shaped extension portion extends upward on the outer peripheral wall of the annular-shaped body and covers an outer peripheral wall of the insulating layer with a top end of the annular-shaped extension portion not higher than an upper surface of the insulating layer, or extends downward on the outer peripheral wall of the annular-shaped body and covers an outer peripheral wall of the base; and when the number of the at least one annular-shaped extension portion is two, an upper half of the annular-shaped extension portion extends upward on the outer peripheral wall of the annular-shaped body and covers the outer peripheral wall of the insulating layer with the top end thereof not higher than the upper surface of the insulating layer, and a lower half of the annular-shaped extension portion extends downward on the outer peripheral wall of the annular-shaped body and covers the outer peripheral wall of the base.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION
[0034] To make those skilled in the art better understand the present disclosure, the following describes an electrostatic chuck provided by the embodiments of the present disclosure in details with reference to the accompanying drawings.
[0035] Referring to
[0036] Moreover, the electrostatic chuck also includes an annular-shaped protection member 8. The annular-shaped protection member 8 is detachably configured on an outer peripheral wall of the heating layer 6. That is, the heating layer 6 is located inside the annular hole of the annular-shaped protection member 8. Whether the heating layer 6 and the annular-shaped protection member 8 contact with each other or not (i.e., whether there is a gap in between) is not limited by the present disclosure. The annular-shaped protection member 8 may be separated from the heating layer 6 without damaging the heating layer 6. Being detachable refers to that the annular-shaped protection member 8 and the heating layer 6 are two structures independent of each other. The damaged annular-shaped protection member 8 may be separately replaced. Replacing the annular-shaped protection member 8 will not damage the heating layer 6, thereby extending a lifespan of the electrostatic chuck and saving process and apparatus costs.
[0037] Preferably, to better protect the heating layer 6 inside the annular-shaped protection member 8 from being etched by the plasma, the annular-shaped protection member 8 is elastic, and is compressed and deformed between the base 5 and the insulating layer 7. That is, a gap between the base 5 and the insulating layer 7 is smaller than or equal to a height of the uncompressed and undeformed annular-shaped protection member 8 in a vertical direction (i.e., an axial direction). As such, the gap in the vertical direction between the base 5 and the insulating layer 7 is blocked and the plasma cannot pass through the gap to reach a peripheral surface of the heating layer 6, thereby achieving separation between the heating layer 6 and the plasma. When being assembled, the annular-shaped protection member 8 may be compressed first in the vertical direction, such that the height of the compressed annular-shaped protection member 8 in the vertical direction is smaller than the gap in the vertical direction between the base 5 and the insulating layer 7. Then, the compressed annular-shaped protection member 8 is enclosed on the peripheral wall of the heating layer 6 and inserted into the gap between the base 5 and the insulating layer 7. The annular-shaped protection member 8 remains compressed and deformed, such that the annular-shaped protection member 8 can be in close contact with the base 5 and the insulating layer 7, thereby sealing the gap. While achieving the detachability, the elastic annular-shaped protection member 8 may seal the gap between the base 5 and the insulating layer 7, separate the heating layer 6 from the plasma, and avoid polluting the wafer by the particles generated from the corrosion of the heating layer 6 exposed directly in the plasma environment. Thus, the wafer processing quality is improved.
[0038] Preferably, the material of the annular-shaped protection member 8 includes a perfluoro rubber. The perfluoro rubber not only is elastic, but also is heat resistant, oxidation resistant, corrosion resistant, and aging resistant due to introducing fluorine atoms into the rubber.
[0039] In one embodiment, when the annular-shaped protection member 8 is not compressed or deformed, a cross-sectional shape in a plane where a central axis of the electrostatic chuck is located (hereinafter simply referred to as the cross-sectional shape) is a rectangle, as shown in
[0040] Preferably, an outer annular surface of the annular-shaped protection member 8 may be a concave surface, which is beneficial for preventing the annular-shaped protection member 8 from contacting with adjacent components. For example, the outer annular surface of the annular-shaped protection member 8 that has a rectangular or square cross-sectional shape is configured to be concave. Specifically, as shown in
[0041] As shown in
[0042] Preferably, in addition to the concave outer annular surface of the annular-shaped protection member 8, a minimum thickness of the annular-shaped protection member 8 in a radial direction is greater than or equal to about 80% of a maximum thickness of the annular-shaped protection member 8 in the radial direction, thereby increasing the lifespan of the annular-shaped protection member 8 and ensuring the desired sealing effect thereof.
[0043] It should be noted that, in one embodiment, when the annular-shaped protection member 8 is not compressed or deformed, the cross-sectional shape in the plane where the central axis of the electrostatic chuck is located may be a rectangle, a square, or a trapezoid. However, the embodiments of the present disclosure do not limit the cross-sectional shape. In practical applications, the cross-sectional shape may also be a circle.
[0044] Preferably, when the cross-sectional shape is the circle, a height of an annular space formed between the outer peripheral wall of the heating layer 6, an upper surface of the base 5, and a lower surface of the insulating layer 7 in the axial direction of the electrostatic chuck is smaller than about 90% of a diameter of the cross-sectional shape, thereby ensuring the desired sealing effect thereof. In addition, in practical applications, a length of the annular space in the radial direction is desired to be larger than a diameter of the uncompressed and undeformed annular-shaped protection member 8. As such, the annular-shaped protection member is ensured to be contained within the outer periphery of the insulating layer 7 or the base 5 when the annular-shaped protection member 8 is compressed or deformed, and the annular-shaped protection member 8 is prevented from contacting with the adjacent components.
[0045]
[0046] Specifically, in one embodiment, the annular-shaped protection member includes an annular-shaped body 10. The annular-shaped body 10 surrounds the outer peripheral wall of the heating layer 6 and is disposed between the base 5 and the insulating layer 7. The annular-shaped body 10 is compressed and deformed between the base 5 and the insulating layer 7. For example, the annular-shaped body 10 is compressed and deformed at least in the vertical direction. That is, a height of the uncompressed and undeformed annular-shaped body 10 in the vertical direction is greater than the gap between the base 5 and the insulating layer 7. The annular-shaped body 10 seals the gap between the base 5 and the insulating layer 7, separates the heating layer 6 from the plasma, prevents the heating layer 6 from being corroded and producing particles due to a direct exposure to the plasma environment, and improves the wafer processing quality. A thickness of the annular-shaped body 10 in the radial direction is greater than a distance between the outer peripheral wall of the heating layer 6 and the outer peripheral wall of the insulating layer 7 to ensure that even if the annular-shaped body 10 is compressed and deformed in the radial direction, the thickness of the annular-shaped body 10 in the radial direction is greater than the distance between the outer peripheral wall of the heating layer 6 and the outer peripheral wall of the insulating layer 7. That is, the outer peripheral wall of the annular-shaped body 10 extends outside the outer peripheral wall of the insulating layer 7.
[0047] Moreover, the annular-shaped protection member also includes a first annular-shaped extension portion 11. The first annular-shaped extension portion 11 extends upward from an upper surface of a protrusion of the annular-shaped body 10, surrounds the outer peripheral wall of the insulating layer 7, and covers and bonds to the outer peripheral wall of the insulating layer 7 to enhance the sealing effect of the gap between the annular-shaped body 10 and the insulating layer 7 and at the same time to prevent the bonded and covered insulating layer 7 from being corroded by the plasma. Further, a top end of the first annular-shaped extension portion 11 does not exceed an upper surface of the insulating layer 7 to avoid affecting the wafer on the insulating layer 7 during the process. Preferably, the top end of the first annular-shaped extension portion 11 is lower than the upper surface of the insulating layer 7. A height of the first annular-shaped extension portion 11 bonding and covering the outer peripheral wall of the insulating layer 7 is approximately between 1 mm and 10 mm. It should be noted that the bonding and covering refers to that no gap exists between the first annular-shaped extension portion 11 and the insulating layer 7 to allow the plasma to pass through, which is hereinafter referred to as the covering. The protrusion of the annular-shaped body 10 refers to a portion of the assembled annular-shaped body 10 that protrudes outside the outer peripheral wall of the insulating layer 7 in the radial direction, regardless of whether the annular-shaped body 10 is compressed or not in the radial direction.
[0048] Alternatively, as shown in
[0049] Alternatively, as shown in
[0050] As can be seen from the above, at least one annular-shaped extension port may be formed on the outer peripheral wall of the annular-shaped body 10. The annular-shaped extension portion may cover only the outer peripheral wall of the insulating layer 7, or only the outer peripheral wall of the base 5, or the outer peripheral walls of both the insulating layer 7 and the base 5. Moreover, when the annular-shaped protection member includes the annular-shaped body 10 and the annular-shaped extension portion, the height of the uncompressed and undeformed annular-shaped body 10 is considered as the height of the uncompressed and undeformed annular-shaped protection member.
[0051] Further, in the electrostatic chuck provided by the embodiments of the present disclosure, the annular-shaped protection member and the heating layer are two structures independent of each other. The annular-shaped protection member surrounds the outer peripheral wall of the heating layer and is detachably disposed on the outer side of the heating layer. As such, the annular-shaped protection member not only protects the heating layer during the manufacturing process, but also can be separately replaced when the annular-shaped protection member is damaged. The heating layer is unaffected during the replacement process, thereby extending the lifespan of the electrostatic chuck and saving the apparatus cost. Thus, the electrostatic chuck provided by the embodiments of the present disclosure has the characteristics of long lifespan, and low maintenance and replacement cost, etc.
[0052] Further, the present disclosure also provides a plasma processing apparatus. The plasma processing apparatus includes a processing chamber. The electrostatic chuck provided by the embodiments of the present disclosure is configured inside the processing chamber.
[0053] In the plasma processing apparatus provided by the embodiments of the present disclosure, because the annular-shaped protection member and the heating layer of the electrostatic chuck are two structures independent of each other, the annular-shaped protection member surrounds the outer peripheral wall of the heating layer and is detachably disposed on the outer side of the heating layer. As such, the annular-shaped protection member not only protects the heating layer during the manufacturing process, but also can be separately replaced when the annular-shaped protection member is damaged. The heating layer is unaffected during the replacement process, thereby extending the lifespan of the electrostatic chuck and saving the apparatus cost.
[0054] It should be understood that the above embodiments are merely exemplary to illustrate the operation principles. However, the present disclosure is not limited to the specific embodiments described herein. Various modifications and improvements will occur to those skilled in the art without departing from the spirit and scope of the present disclosure. These modifications and improvements are also considered to be within the scope of the present disclosure.