Apparatus and method for sealing a vacuum chamber

Coating apparatus – Gas or vapor deposition – Chamber seal

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C118S715000, C220S315000

Reexamination Certificate

active

06193804

ABSTRACT:

FIELD OF THE INVENTION
The present invention generally relates to an apparatus and a method for sealing a vacuum chamber and more particularly, relates to an apparatus and a method for sealingly engaging an upper chamber lid to a lower chamber lid of a vacuum process chamber by using a support frame for mounting the upper chamber lid thereto through a universal joint connecting between the support frame and the center of the upper chamber lid such that the upper and the lower chamber lids are intimately engaged together and four compressible springs mounted on the support frame for applying compressive pressure on the upper chamber lid for achieving a vacuum-tight seal.
BACKGROUND OF THE INVENTION
In the semiconductor device fabrication processes, vacuum process chambers are widely used for conducting various chemical or physical processes. For instance, vacuum process chambers are widely used in deposition processes such as chemical vapor deposition or physical vapor deposition; in coating processes such as a spin coating process for a photoresist material or a spin-on-glass material; and various other fabrication processes. In any of the processes, a vacuum chamber may be constructed of an upper chamber and a lower chamber, or an upper chamber lid and a lower chamber lid. The structure is designed to facilitate the loading and unloading of a semiconductor substrate into or out of a process chamber. For instance, in one of the common constructions for a vacuum process chamber, the lower chamber lid can be moved up and down while the upper chamber lid stays stationary with a substrate platform positioned in a cavity formed between the lower chamber lid and the upper chamber lid. A robot arm is used for reaching into the chamber cavity for the loading and unloading of substrates. After a substrate is properly seated on the substrate platform, the platform moves into its process position and the lower chamber lid closes onto the upper chamber lid to effect a vacuum-tight seal.
In the vacuum process chamber discussed above, the upper chamber lid is frequently fixedly attached to a support frame for the operation of the chamber. Since the support frame for the upper chamber lid is not always perfectly centered in relation to the lower chamber lid, the upper and the lower chamber lids are frequently not perfectly aligned. This results in leakage in the vacuum chamber and specifically, leakage around the edges of the chamber. For instance, in a spin coating apparatus for a photoresist material, it has been observed that during the coating of an adhesion promoter layer prior to the coating of the photoresist material, the process produces wafer edge defects in an area of approximately 8~20 mm wide around the wafer edge. The defects are caused by a leakage in the vacuum process chamber when ambient air leaks into the chamber and cause defect formation around the edge of the wafer. Typical defects formed are film coating pattern shift and film lifting.
An illustration for a conventional mounting method for a vacuum process chamber is shown in FIG.
1
. The vacuum process chamber
10
consists of an upper chamber
14
and a lower chamber
16
used for the processing of a wafer
20
contained in a vacuum cavity formed when the upper chamber
14
and the lower chamber
16
are tightly closed together. The upper chamber
14
is rigidly and fixedly mounted by a mounting means
18
to a support frame
12
for mating with the lower chamber
16
. It should be noted that the apparatus
10
is shown in
FIG. 1
for illustration purpose only and in a much simplified manner. Since the upper chamber
14
, or the upper chamber lid is rigidly and fixedly mounted to the support frame
12
through mounting means
18
, a perfect alignment of the upper chamber
14
to the lower chamber
16
when the lower chamber
16
is moved up to close on the upper chamber
14
is extremely difficult. The rigid connection provided between the upper chamber
14
and the support frame
12
does not allow any lateral movement of the upper chamber
14
during the closing step for the upper and lower chambers.
It is therefore an object of the present invention to provide an apparatus for sealingly engaging an upper chamber lid and a lower chamber lid of a vacuum process chamber together that does not have the drawbacks or shortcomings of the conventional mounting apparatus.
It is another object of the present invention to provide an apparatus for sealingly engaging an upper chamber lid and a lower chamber lid of a vacuum process chamber together that permits lateral movement of the upper chamber lid relative to the lower chamber lid.
It is a further object of the present invention to provide an apparatus for sealingly engaging an upper chamber lid and a lower chamber lid of a vacuum process chamber together by mounting the upper chamber lid to a support frame via an universal joint device.
It is another further object of the present invention to provide an apparatus for sealingly engaging an upper chamber lid and a lower chamber lid of a vacuum process chamber together by utilizing a universal joint between the upper chamber lid and a support frame the lid is mounted and a plurality of compressible springs mounted on the support frame for exerting downward pressure on the upper chamber lid.
It is still another object of the present invention to provide an apparatus for sealingly engaging an upper chamber lid and a lower chamber lid of a vacuum process chamber together by utilizing a universal joint for lateral movement of the upper chamber lid and four compressible springs for achieving vacuum-tight seal.
It is yet another object of the present invention to provide a vacuum process chamber that includes a sealing means disposed between an upper chamber lid and a support member which includes a universal joint for allowing 360° movement of the lid and a plurality of compressible spring for effecting a seal between the upper chamber lid and a lower chamber lid.
It is still another further object of the present invention to provide a vacuum process chamber that utilizes a universal joint between an upper chamber lid and a support member for allowing lateral movement of the upper chamber lid and four compressible springs equally spaced from each other for exerting a downward pressure on the upper chamber lid effecting a vacuum-tight seal with a lower chamber lid.
It is yet another further object of the present invention to provide a method for sealingly engaging an upper chamber lid to a lower chamber lid forming a vacuum process chamber by attaching the upper chamber lid to a support frame via an universal joint and at least three compressible springs projected downwardly from the support member for exerting pressure on the upper chamber lid and effecting a vacuum-tight seal between the upper and lower chamber lids.
SUMMARY OF THE INVENTION
In accordance with the present invention, an apparatus and a method for sealing a vacuum process chamber are provided.
In a preferred embodiment, an apparatus for sealingly engaging an upper chamber lid and a lower chamber lid of a vacuum process chamber together is provided which includes an upper lid support frame adapted for mounting a top end of spaced-apart compressible spring members at four corners and a top end of a universal joint member at a center, an upper chamber lid which has a top surface adapted for contacting a bottom end of the spaced-apart compressible spring members at four corners and a bottom end of a universal joint member at a center, the upper chamber lid further includes a bottom surface adapted for sealingly engaging a top surface of the lower chamber lid, and a universal joint member connecting the upper chamber lid support frame and the top surface of the upper chamber lid for 360° movement of the upper chamber lid such that the bottom surface of the upper lid intimately engages the top surface of the lower chamber lid, whereby the compressible spring members mounted on the upper chamber lid support frame pushes the upper chamber lid onto the lower chamber lid

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Apparatus and method for sealing a vacuum chamber does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Apparatus and method for sealing a vacuum chamber, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus and method for sealing a vacuum chamber will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2579405

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.