JP2010043745A - Method and apparatus for providing floating seal for chamber door - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for reliably sealing a chamber door. <P>SOLUTION: This method is provided that includes a step of isolating a sealing surface from a chamber wall of a chamber and a step of sealing the chamber between the sealing surface and the chamber wall. This apparatus is provided that includes a chamber wall section prone to deflection, a stationary section providing the sealing surface, and a flexible bellows attached to the chamber wall section and the stationary section. A system is also provided that includes the chamber including the chamber wall having an opening part, the door disposed to seal the opening part, the sealing surface adjacent to the opening part and isolated from the chamber wall, and a seal between the sealing surface and the chamber wall. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention claims priority from US Provisional Application No. 60 / 598,039, filed Aug. 2, 2004, entitled "Methods And Apparatus For Providing A Floating Seal ForChamber Doors", for all purposes. All of which are incorporated herein for reference.

  This application also claims priority from US patent application Ser. No. 11 / 145,018, filed Aug. 2, 2005, entitled “Methods And Apparatus For Sealing A Chamber”, and is a continuation-in-part of that, This application itself includes US Provisional Application No. 60 / 587,114, filed July 12, 2004, and US Provisional Application No. 60 / 576,906, filed June 2, 2004. We claim priority to both issues, all of which are incorporated herein by reference for all purposes.

  The present invention relates generally to flat panel display and / or electronic device manufacturing chambers and methods and apparatus for sealing the doors of such chambers.

  In many electronic device manufacturing processes, vacuum processing chambers are widely used to perform a variety of chemical or physical processes. For example, vacuum processing chambers are widely used in deposition processes such as chemical vapor deposition or physical vapor deposition, coating processes such as spin coating processes for photoresist materials or spin-on glass materials, and various other manufacturing processes. in use. In addition, the transfer chamber is similarly operated in a vacuum to prevent contamination from foreign particles. Conventional chambers are sealed using a door that relies on an O-ring or similar sealing element at the door that contacts the sealing surface at the chamber wall around the door opening.

  To prevent leakage, the door must be reliably sealed whenever it is closed. Therefore, a method and apparatus for reliably sealing a chamber door is desired.

  In one embodiment, the present invention includes isolating the sealing surface from the chamber wall of the chamber and sealing the chamber between the sealing surface and the chamber wall.

  In another aspect, the present invention provides an apparatus that includes a chamber wall section that is prone to deflection, a fixed section that provides a sealing surface, and a flexible bellows attached to the chamber wall section and the fixed section.

  In an additional aspect, the invention provides a chamber wall having an opening, a door positioned to seal the opening, a sealing surface adjacent to the opening and isolated from the chamber wall, a seal between the sealing surface and the chamber wall. A system comprising a chamber comprising:

  In yet another aspect, the present invention provides a replaceable part including a flexible bellows including a first flange portion, a second flange portion, a first flange portion, and a flexible portion attached to the second flange portion. To do.

  Other features and aspects of the present invention will become more fully apparent from the following detailed description of the exemplary embodiments, the appended claims and the accompanying drawings.

FIG. 1A is a cross-sectional view of a chamber opening with an example of a floating seal using a flexible bellows, according to some embodiments of the present invention. FIG. 1B is a perspective view of the chamber opening of FIG. 1A. FIG. 4 is a cut perspective view of one example of a floating seal using a molded rubber bellows, according to some embodiments of the present invention. FIG. 3 is a cutaway exploded view of an example of a portion of a floating seal, in accordance with some embodiments of the present invention. 1 is a cross-sectional perspective view of an example of a floating seal using a flexible metal bellows, according to some embodiments of the present invention. FIG. FIG. 5 is a cutaway perspective view of an example of a portion of a floating seal, according to some embodiments of the present invention. 6A is a perspective view of the chamber opening of FIG. FIG. 6B is a detailed view of the enclosed portion of FIG. 6A. 6C is a cross-sectional view taken along line CC in the enclosed portion of FIG. 6A. FIG. 6D is an exploded perspective view of a portion of a flexible bellows, according to some embodiments of the present invention.

  The present invention provides improved methods and apparatus (eg, processing chambers, transfer chambers, load locks, etc.) and other devices that require a hermetic seal for sealing the chamber. By providing a fixed floating sealing surface, the present invention prevents the sealing surface from moving relative to the door sealing element. This avoids wear and wear of the door sealing element and prevents the generation of contaminating particles. Thus, by providing a mechanically isolated sealing surface (eg, a sealing surface surrounding the chamber opening), the present invention allows the chamber door to be closed even if the chamber wall is subjected to significant deflection. Ensure that a consistent seal can be achieved. In various embodiments, the sealing surface “floats” with respect to the chamber wall so that it is not subject to displacement when the chamber wall deflects due to changes in vacuum pressure or due to thermal expansion / contraction. As such, the method and apparatus of the present invention provides a means for preventing the sealing surface from sliding relative to the door sealing element, preventing the generation of particles, preventing wear and wear of the sealing element, and ensuring proper sealing. I will provide a.

  The inventor of the present invention believes that an O-ring or similar may result from the deflection of the chamber wall resulting from the difference in chamber pressure and temperature between the chamber and the surrounding atmosphere (eg, the atmospheric pressure outside the adjacent chamber and / or the chamber). It has been found that the sealing element itself does not consistently form a good seal. The inventor has further noticed that the sealing elements used as seals in conventional chamber doors move through the sealing surface under pressure and / or thermal expansion under pressure, resulting in abrasion. Is to receive. This abrasion results in the generation of contaminating particles, wear of the sealing elements, and ultimately poor sealing. This problem grows over time as the chamber repeats different processes and the sealing element further deteriorates from wear. The problem is particularly acute in chambers such as load locks that frequently require "pump down" (depressurization) and venting (repressurization).

  Furthermore, in tool designs that use multiple chambers that share a common wall, such as large “stacked” chambers (eg, double, triple load locks), the different chambers are under different pressures at the same time, The deflection becomes cumulative from one chamber to the other. This situation can cause significant displacement of the sealing surface with respect to the door sealing element.

  In some embodiments of the present invention, the sealing surface can be supported by a flexible bellows, which leaves the sealing surface fixed relative to the door sealing element as the chamber wall deflects. The flexible bellows can also seal the gap between the chamber wall and the sealing surface. In some embodiments, the bellows includes a molded rubber bellows attached to both the sealing surface and the flexible sheet or plate. The flexible sheet can be attached to a rigid support member inside (or outside) the chamber wall that has minimal deflection or that is not subject to displacement when the chamber wall is deflected.

  In alternative or additional embodiments, the size of the gap between the chamber wall and the sealing surface may be selected to accommodate the maximum possible amount of chamber deflection. For example, in an AKT-5KA transfer chamber manufactured by Applied Materials, the deflection of the chamber at the center of the door opening is approximately 4 mm, and according to the present invention, there is a gap for accommodating such deflection. Is approximately 8 mm. Similarly, the size and elasticity of the bellows can be selected to accommodate the maximum possible amount of chamber deflection.

  In some embodiments, only the sealing surfaces above and below the chamber opening (eg, door opening) can be isolated from the deflection of the chamber wall. In such a floating seal embodiment, the deflection of the sealing surface at the side of the chamber door opening may not be significant. FIG. 1A is a cross-sectional view, and FIG. 1B is a partial perspective view, each showing an exemplary embodiment of a floating seal device according to the present invention. Note that the chamber door 102 contacts a stationary sealing surface 104 separated by a gap 106 from the chamber body 108. Also note that the gap 106 is sealed by a flexible bellows 110.

  Referring to the floating seal device 100 according to the specific example illustrated in FIGS. 1A and 1B, in some embodiments, the individual features and components of the present invention are coordinated with each other as shown. May be. In some embodiments, the features and components may be coordinated quite differently than illustrated. For example, in the AKT-25KA transfer chamber described above, the height (H) of the chamber door opening 112 is approximately 127 mm, and the width (W) of the chamber door opening 112 (and / or the deflection gap). 106) may be approximately 1524 mm. In such an apparatus 100, at least in one embodiment of the present invention, the size (G) of the gap 106 between the chamber body 108 and the sealing surface 104 is approximately 8 mm, the chamber door opening 112 and the gap 106 The distance (D) between may be approximately 25 mm. The thickness (T) of the chamber body 108 in the vicinity of the door 102 may be approximately 50 mm, and the thickness (for example, the dimension U) into the chamber may be approximately 113 mm.

  The cumulative size of the two gaps 106 (eg, twice dimension G) is selected so that both gaps 106 can jointly accommodate the maximum amount of potential deflection of the chamber body / wall 108. Is possible.

  Opening FIG. 2, a more detailed cutaway perspective view of the previously described embodiment of the floating seal device 100 according to the present invention is provided. During pumping and venting, the sealing surface 104 attached to the flexible sheet / plate 202 remains secured to the door sealing element 204 even when the chamber wall 108 is deflected. Therefore, the present invention prevents or reduces the wear of the sealing element and the generation of contamination particles.

  Opening FIG. 3 shows more detail of the top of the previously described embodiment 100 and seals the gap 106 between the flexible sheet / plate 202 (with the sealing surface 104 attached to the top) and the chamber body 108. FIG. 2 is a partial perspective view illustrating an example of a molded rubber bellows 110 that can be used for this purpose, which is disassembled and cut. In the illustrated embodiment, the mounting frame 304 is used to clamp (or otherwise fasten) one flange edge 306 of the bellows 110 to the chamber body 108, and the sealing surface 104 is the other of the bellows 110. Used to clamp (or otherwise clamp) flange edge 308 to flexible sheet / plate 302. The flexible portion 310 of the flexible bellows 110 (eg, flange portion 306 to clamp the bellows 110 to the chamber 108 and sealing surface 104 when used in the previously described exemplary embodiment of the AKT-25KA transfer chamber. , 308) may be dimensioned to fit tightly within the gap 106 between the chamber body 108 and the sealing surface 104 / flexible sheet / plate 302, so that the length of the bellows 110 is reduced. The traveling contact bead (not shown) may be approximately 9 mm higher.

  In some embodiments, the bellows 110 may be made from any suitable material, such as a fluorocarbon (FKM) rubber composite. Alternatively, in some embodiments, other compounds such as butyl (IIR), ethylene propylene (EPDM), fluorosilicone (FVMQ), hydrin (CO / ECO), neoprene (CR), nitrile (NBR) ), Silicone (VMQ), styrene butadiene rubber (SBR), or the like. Bellows made from rubber composites seal the gap between the sealing surface (and / or flexible sheet / plate) and the chamber wall, are relatively low cost, low maintenance, easy to replace, Provides an easy to manufacture means.

  In some embodiments, the flexible bellows may be implemented using thin, flexible convolution sheet metal. Any suitable metal can be used, for example stainless steel. Flexible bellows made of thin and folded metal are much more durable and reliable than rubber composites, making maintenance difficult like a seal between the processing chamber and the transfer chamber May be suitable for use in different applications or inaccessible places. Like the above-described embodiment using the rubber synthetic fiber bellows, the flexible metal bellows absorbs the deflection of the chamber wall without moving the sealing surface.

  An example embodiment of the present invention using a metal bellows 400 is shown in FIG. FIG. 4 is a cut perspective view in which the sealing surface 104 remains attached and secured to a rigid structure 402 outside the chamber, while the flexible area 404 is attached to the chamber wall 108. Illustrates bending when the wall 108 bends. The metal bellows 400 is disposed between the fixed sealing surface 104 and the flexible area 404 and creates a flexible seal in the slit or gap 106 between the sealing surface 104 and the flexible area 404. In some embodiments, the slit / gap size can be selected to accommodate the expected maximum amount of chamber wall deflection that may occur.

  Turning to FIG. 5, a perspective cross-sectional view of a legitimate flexible bellows 400, a fixed sealing surface area 104, and a flexible area 404 is shown. Note that the image of FIG. 5 has been rotated 90 degrees from the depiction of FIG. Note also that only a portion of areas 104 and 404 are depicted to illustrate bellows 400. In some embodiments, a fully flexible floating seal may form the entire chamber opening 112 (FIG. 4).

  6A-6D, details of an example configuration of a flexible metal bellows 400 are depicted. 6A is a perspective view of the chamber opening 112 of FIG. FIG. 6B is a detailed view of the enclosed portion 604 of FIG. 6A. 6C is a cross-sectional view taken along line CC in the enclosed portion 604 of FIG. 6A. FIG. 6D is an exploded perspective view of a part of the flexible bellows 400.

  With particular reference to FIG. 6A, one example of the depicted embodiment is noted that the sealing surface 104 above and below the chamber opening 112 is isolated from the chamber wall 108, but the side 602 is not isolated. I want to be. As previously indicated, in some embodiments, one side 602 of the chamber door opening 112 may not be essential. As shown in FIGS. 6B and 6D, both ends of a sheet metal (for example, stainless steel) 608 in which a corner block 606 or a cone is thinly folded to form a single flexible metal bellows 400 are formed. It may be attached to the part (for example, welded). An example of such a single flexible metal bellows 400 may be formed from stainless steel having a length of approximately 1550 mm, a height of 8 mm, a depth of 12 mm, and a thickness of 0.15 mm. The edge 610 of the bellows 400 may then be welded to the chamber wall 108 and the sealing surface 104, as shown in FIG. 6C. As shown in FIG. 6C, in some embodiments, the groove 612 is milled along one side of the flexure gap 104 in the chamber wall 108 and sealing surface 104 to provide a flexible metal bellows 400. It should be noted that edges 614, 616 of suitable thickness may be provided for welding. For example, in some embodiments, the groove 612 may be approximately 4 mm deep and 2 mm wide.

  Also, like the rubber composite bellows, the size and elasticity of the flexible metal bellows 400 may be selected to accommodate the maximum amount of chamber deflection expected.

  Although the present invention has been described in several lengths and with some special circumstances with respect to some described embodiments, it is limited to such special circumstances or embodiments or embodiments of special circumstances. It is not intended to be limiting, but from the standpoint of the prior art, the appended claims are accorded the greatest possible interpretation and effectively encompass the intended scope of the present invention.

  DESCRIPTION OF SYMBOLS 100 ... Floating seal device, 102 ... Chamber door, 104 ... Fixed sealing surface, 106 ... Gap, 108 ... Chamber body, chamber wall, 110 ... Flexible bellows, 112 ... Opening, 202 ... Flexible sheet / Plate, 204 ... door sealing element, 306 ... flange edge, 308 ... flange edge, 310 ... flexible part, 400 ... metal bellows, 404 ... flexible area, 602 ... side part, 604 ... enclosed part, 606 ... Corner block, 608 ... Thin folded metal sheet, 610 ... Edge, 612 ... Groove, 614 ... Edge, 616 ... Edge

Claims (8)

A replaceable part with a flexible bellows, said flexible bellows:
A first flange portion;
A second flange portion;
A flexible portion attached to the first flange portion and the second flange portion;
The replaceable part comprising:   The replaceable part of claim 1, wherein the flexible bellows is comprised of a molded mixture.   The first flange portion is adapted to be attached to a chamber wall that is prone to deflection, and the second flange portion is adapted to be attached to an isolated sealing surface. Replaceable parts.   The replaceable part of claim 3, wherein the flexible portion is adapted to accommodate a maximum expected amount of deflection of the chamber wall.   The replaceable part of claim 1, wherein the flexible bellows comprises a flexible convolution of sheet metal.   The replaceable component of claim 5, wherein the flexible bellows further includes a corner block attached to each end of the flexible portion.   6. The replaceable part of claim 5, wherein the first flange portion and the second flange portion are an integral part of the flexible portion.   The first flange portion is adapted to be welded to an edge formed in the chamber wall, and the second flange portion is adapted to be welded to an edge formed in an isolated sealing surface. The replaceable part of claim 7.

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