U.S. patent application number 12/199456 was filed with the patent office on 2009-04-02 for clamp mechanism for a backing plate disposed in a pecvd chamber.
Invention is credited to Sam H. KIM, Beom Soo PARK, William N. STERLING.
Application Number | 20090083953 12/199456 |
Document ID | / |
Family ID | 40506569 |
Filed Date | 2009-04-02 |
United States Patent
Application |
20090083953 |
Kind Code |
A1 |
KIM; Sam H. ; et
al. |
April 2, 2009 |
CLAMP MECHANISM FOR A BACKING PLATE DISPOSED IN A PECVD CHAMBER
Abstract
Embodiments described herein relate to a clamp mechanism for a
backing plate disposed in a PECVD chamber, comprising an upper
clamp portion fixed to an interior portion of a chamber lid, and a
lower clamp portion in sliding contact with the upper clamp portion
and the backing plate, wherein the lower clamp portion comprises at
least one fastener disposed through the lower clamp portion and the
chamber lid, the at least one fastener comprising an adjustment
member, and wherein rotation of the adjustment member causes
lateral movement and compression to the backing plate.
Inventors: |
KIM; Sam H.; (San Ramon,
CA) ; PARK; Beom Soo; (San Jose, CA) ;
STERLING; William N.; (Santa Clara, CA) |
Correspondence
Address: |
PATTERSON & SHERIDAN, LLP - - APPM/TX
3040 POST OAK BOULEVARD, SUITE 1500
HOUSTON
TX
77056
US
|
Family ID: |
40506569 |
Appl. No.: |
12/199456 |
Filed: |
August 27, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60975691 |
Sep 27, 2007 |
|
|
|
Current U.S.
Class: |
24/460 |
Current CPC
Class: |
Y10T 24/44043 20150115;
H01J 37/32458 20130101; C23C 16/4409 20130101 |
Class at
Publication: |
24/460 |
International
Class: |
A44B 21/00 20060101
A44B021/00 |
Claims
1. A clamp mechanism for a backing plate disposed in a plasma
chamber, comprising: a first clamp portion fixed to an interior
portion of a chamber lid assembly, the first clamp portion having
at least one first slanted contact surface; and a second clamp
portion having at least one second slanted contact surface in
sliding contact with the first slanted contact surface and the
backing plate, the second clamp portion comprising: at least one
fastener disposed through the second clamp portion and the interior
portion of the chamber lid assembly, the at least one fastener
comprising an adjustment member exposed to an exterior of the
plasma chamber and providing lateral movement of the second clamp
portion relative to the backing plate and the first clamp portion
by rotation of the adjustment member.
2. The clamp mechanism of claim 1, wherein the first clamp portion
and the second clamp portion are made of a polyetheretherketone
(PEEK) material.
3. The clamp mechanism of claim 1, wherein the first clamp portion
is fixed to the interior portion of the chamber lid assembly by a
screw.
4. The clamp mechanism of claim 1, wherein the at least one
fastener is a bolt.
5. The clamp mechanism of claim 4, wherein the bolt is an Allen
head bolt.
6. The clamp mechanism of claim 4, wherein the bolt is a hex head
bolt.
7. The clamp mechanism of claim 4, wherein the bolt includes a
rotation prevention feature.
8. The clamp mechanism of claim 1, wherein the adjustment member is
a nut.
9. The clamp mechanism of claim 8, wherein the nut is made of
stainless steel and includes an anti-bind or anti-gall coating.
10. The clamp mechanism of claim 9, wherein the coating is made of
tungsten disulfide or dicronite.
11. A plasma chamber having a lid assembly including a backing
plate, a cover spaced-apart from the backing plate by a wall, and a
plurality of clamp mechanisms disposed in the area between the lid
and the backing plate, each of the plurality of clamp mechanisms
comprising: a first clamp portion fixed to an interior portion of
the wall, the first clamp portion having at least one first slanted
contact surface; and a second clamp portion having at least one
second slanted contact surface in sliding contact with the first
slanted contact surface and the backing plate, the second clamp
portion comprising: at least one fastener disposed through the
second clamp portion and the wall, the at least one fastener
comprising an adjustment member exposed to an exterior of the
plasma chamber and providing lateral movement of the second clamp
portion relative to the backing plate and the first clamp portion
by rotation of the adjustment member.
12. The clamp mechanism of claim 11, wherein the first clamp
portion is fixed to the wall by a screw.
13. The clamp mechanism of claim 11, wherein the at least one
fastener is a bolt.
14. The clamp mechanism of claim 13, wherein the bolt is an Allen
head bolt.
15. The clamp mechanism of claim 13, wherein the bolt is a hex head
bolt.
16. The clamp mechanism of claim 13, wherein the bolt includes a
rotation prevention feature.
17. The clamp mechanism of claim 11, wherein the adjustment member
is a nut.
18. The clamp mechanism of claim 17, wherein the nut is made of
stainless steel and includes an anti-bind or anti-gall coating.
19. The clamp mechanism of claim 18, wherein the coating is made of
tungsten disulfide or dicronite.
20. A plasma chamber having a lid assembly including a backing
plate, a cover spaced-apart from the backing plate by a wall, and a
plurality of clamp mechanisms disposed in the area between the lid
and the backing plate, each of the plurality of clamp mechanisms
comprising: a first clamp portion fixed to an interior portion of
the wall by a screw, the first clamp portion having at least one
first slanted contact surface; and a second clamp portion having at
least one second slanted contact surface in sliding contact with
the first slanted contact surface and the backing plate, the second
clamp portion comprising: at least one fastener disposed through
the second clamp portion and the wall, the at least one fastener
comprising a nut exposed to an exterior of the plasma chamber and
providing lateral movement of the second clamp portion relative to
the backing plate and the first clamp portion by rotation of the
nut.
21. The clamp mechanism of claim 20, wherein the at least one
fastener is a bolt.
22. The clamp mechanism of claim 21, wherein the bolt is an Allen
head bolt.
23. The clamp mechanism of claim 21, wherein the bolt is a hex head
bolt.
24. The clamp mechanism of claim 21, wherein the bolt includes a
rotation prevention feature.
25. The clamp mechanism of claim 20, wherein the nut is made of
stainless steel and includes an anti-bind or anti-gall coating.
26. The clamp mechanism of claim 25, wherein the coating is made of
tungsten disulfide or dicronite.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims benefit of U.S. Provisional Patent
Application Ser. No. 60/975,691 (Attorney Docket No. 11816L), filed
Sep. 27, 2007, which is herein incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] Embodiments of the present invention generally relate to an
apparatus used in the fabrication of electronic devices on large
area substrates and related chamber hardware, and more
specifically, to a clamp mechanism for a backing plate disposed in
a plasma-enhanced chemical vapor deposition (PECVD) chamber used
for deposition of material on large area substrates.
[0004] 2. Description of the Related Art
[0005] Plasma Enhanced Chemical Vapor Deposition (PECVD) is a
method for depositing a material onto a substrate by igniting
process gases into a plasma state. Process gas may be provided to a
gas distribution plate or showerhead disposed in an opposing
relationship to a temperature controlled substrate support assembly
or susceptor disposed within a sealable processing volume in a
processing chamber. The susceptor supports a large area substrate
and the process gases are disassociated above the substrate to
deposit material forming electronic devices, such as thin film
transistors (TFT's), organic light emitting diodes (OLED's), and
photovoltaic cells used in solar cell fabrication. Negative
pressure may be provided to the processing volume and the process
gases are disassociated by thermal energy, vacuum, radio frequency
(RF) power, and combinations thereof, to form a plasma and
facilitate deposition of materials on the large area substrate.
[0006] An upper portion of the processing chamber includes the
showerhead and associated hardware, such as a backing plate, that
may be coupled to a lid assembly. The lid assembly generally
includes a cover and process gas inlets, and the cover may support
a remote plasma unit. The backing plate is typically disposed above
the showerhead and may be configured to facilitate support of the
showerhead. Generally, a perimeter of the backing plate is adapted
to compress a seal between the perimeter of the backing plate and
the lid assembly to form an upper boundary of the processing
volume. The seal typically includes a polymer or an elastomeric
material that provides a vacuum-tight interface and may
additionally facilitate electrical insulation. Thermal forces
and/or pressure cycling may cause the interface to loosen, which
may cause the interface to be compromised.
[0007] Therefore, there is a need in the art for an improved
assembly for ensuring vacuum sealing of the chamber.
SUMMARY OF THE INVENTION
[0008] Embodiments described herein relate to a clamp mechanism for
a backing plate disposed in a PECVD chamber. Embodiments of the
clamp mechanism provide and maintain a compressive force to the
backing plate to facilitate vacuum sealing of the chamber. The
clamp mechanism as described herein provides adjustment of the
clamp mechanism from a location outside of the processing chamber
without disassembly of the chamber.
[0009] In one embodiment, a clamp mechanism for a backing plate
disposed in a plasma chamber is described. The clamp mechanism
includes a first clamp portion fixed to an interior portion of a
chamber lid assembly, the first clamp portion having at least one
first slanted contact surface, and a second clamp portion having at
least one second slanted contact surface in sliding contact with
the first slanted contact surface and the backing plate. The second
clamp portion includes at least one fastener disposed through the
second clamp portion and the interior portion of the chamber lid
assembly, the at least one fastener comprising an adjustment member
exposed to an exterior of the plasma chamber and providing lateral
movement of the second clamp portion relative to the backing plate
and the first clamp portion by rotation of the adjustment
member.
[0010] In another embodiment, a plasma chamber having a lid
assembly including a backing plate, a cover spaced-apart from the
backing plate by a wall, and a plurality of clamp mechanisms
disposed in the area between the lid and the backing plate is
described. Each of the plurality of clamp mechanisms include a
first clamp portion fixed to an interior portion of the wall, the
first clamp portion having at least one first slanted contact
surface, and a second clamp portion having at least one second
slanted contact surface in sliding contact with the first slanted
contact surface and the backing plate. The second clamp portion
includes at least one fastener disposed through the second clamp
portion and the wall, the at least one fastener comprising an
adjustment member exposed to an exterior of the plasma chamber and
providing lateral movement of the second clamp portion relative to
the backing plate and the first clamp portion by rotation of the
adjustment member.
[0011] In another embodiment, a plasma chamber having a lid
assembly including a backing plate, a cover spaced-apart from the
backing plate by a wall, and a plurality of clamp mechanisms
disposed in the area between the lid and the backing plate is
described. Each of the plurality of clamp mechanisms include a
first clamp portion fixed to an interior portion of the wall by a
screw, the first clamp portion having at least one first slanted
contact surface, and a second clamp portion having at least one
second slanted contact surface in sliding contact with the first
slanted contact surface and the backing plate, the second clamp
portion comprising at least one fastener disposed through the
second clamp portion and the wall, the at least one fastener
comprising a nut exposed to an exterior of the plasma chamber and
providing lateral movement of the second clamp portion relative to
the backing plate and the first clamp portion by rotation of the
nut.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] So that the manner in which the above recited features of
the present invention can be understood in detail, a more
particular description of the invention, briefly summarized above,
may be had by reference to embodiments, some of which are
illustrated in the appended drawings. It is to be noted, however,
that the appended drawings illustrate only typical embodiments of
this invention and are therefore not to be considered limiting of
its scope, for the invention may admit to other equally effective
embodiments.
[0013] FIG. 1 is a schematic cross-sectional view of one embodiment
of a PECVD chamber.
[0014] FIG. 2 is an isometric view of on embodiment of a clamp
device.
[0015] FIG. 3 is a cross-sectional view of the clamp device of FIG.
2.
[0016] FIG. 4 is a cross-sectional view of one embodiment of a
nut.
[0017] To facilitate understanding, identical reference numerals
have been used, where possible, to designate identical elements
that are common to the figures. It is contemplated that elements
disclosed in one embodiment may be beneficially utilized on other
embodiments without specific recitation.
DETAILED DESCRIPTION
[0018] FIG. 1 is a schematic cross-sectional view of one embodiment
of a plasma enhanced chemical vapor deposition (PECVD) system 100.
The system 100 may be a PECVD system available from AKT.RTM., a
division of Applied Materials, Inc., of Santa Clara, Calif. The
system 100 includes a processing chamber 102 having walls 106, a
backing plate 101, and a bottom 108 that partially define a process
volume 112. The process volume 112 is typically accessed through a
selectively sealable port (not shown) in the walls 106 that
facilitates transfer of a large area substrate 140 into and out of
the processing chamber 102. The substrate 140 may be made of glass,
polymers, or other material capable of having electronic devices
formed thereon and typically includes a surface area of 2.2
meters.sup.2, or greater. The walls 106 and bottom 108 are
typically fabricated from aluminum or other material compatible
with processing.
[0019] A temperature controlled susceptor or substrate support
assembly 138 is centrally disposed within the processing chamber
102. The substrate support assembly 138 supports the large area
substrate 140 during processing. In one embodiment, the substrate
support assembly 138 comprises an aluminum body 124 that includes
an embedded heater 132. The heater 132, such as a resistive
element, disposed in the support assembly 138, is coupled to a
power source 174 that controllably heats the support assembly 138
and the large area substrate 140 positioned thereon to a
predetermined temperature. Typically, in a CVD process, the heater
132 maintains the large area substrate 140 at a uniform temperature
between about 150.degree. to at least about 460.degree. C.,
depending on the deposition processing parameters for the material
being deposited.
[0020] The substrate support assembly 138 has a lower side 126 and
a substrate receiving surface 134 and the substrate receiving
surface 134 supports the large area substrate 140. The lower side
126 has a stem 142 which couples the substrate support assembly 138
to a lift system (not shown) that moves the substrate support
assembly 138 between an elevated processing position (as shown) and
a lowered position that facilitates substrate transfer to and from
the processing chamber 102. The stem 142 additionally provides a
conduit for electrical and thermocouple leads between the substrate
support assembly 138 and other components of the chamber 102. A
bellows 146 may be coupled between the substrate support assembly
138 (or the stem 142) and the bottom 108 of the processing chamber
102. The bellows 146 facilitates vacuum sealing around the stem 142
while facilitating vertical movement of the substrate support
assembly 138.
[0021] The substrate support assembly 138 has a plurality of holes
128 disposed therethrough that accept a plurality of lift pins 150.
The lift pins 150 are comprised of ceramic or anodized aluminum.
When the substrate support assembly 138 is lowered, a lower portion
of the lift pins 150 also lower to make contact with the chamber
bottom 108. As the substrate support assembly 138 is lowered
further, the upper portion of the lift pins 150 are elevated above
the substrate receiving surface 134 to space the large area
substrate 140 apart from the substrate receiving surface 134 to
facilitate transfer of the large area substrate by allowing access
to a robot blade or end effector.
[0022] In one embodiment, the substrate support assembly 138 is
grounded such that radio frequency (RF) power, supplied by a power
source 122, is provided to a showerhead 118 positioned between the
lid assembly 110 and substrate support assembly 138, or other
electrode positioned within or near the lid assembly of the
chamber. The RF power excites gases present in the process volume
112 between the substrate support assembly 138 and the showerhead
118 to facilitate deposition on the substrate 140. The RF power
from the power source 122 is generally selected commensurate with
the size of the substrate to drive the chemical vapor deposition
process.
[0023] The walls 106 support a lid assembly 110 that includes a lid
cover 105 and a backing plate support member 111 facilitating
support of the backing plate 101. The backing plate 101 is a
substantially rigid plate and may support the showerhead 118. The
backing plate 101 also includes an inlet 180 coupled to a gas
source 104 by a conduit 121 through which process gases, provided
by the gas source 104, are introduced into the processing chamber
102. The inlet 180 is also coupled to a cleaning source 182, which
may comprise a remote plasma unit disposed on and coupled to the
lid cover 105 by brackets 181. The cleaning source 182 typically
provides a cleaning agent, such as a molecular or disassociated
fluorine containing gas that is introduced into the processing
chamber 102 to remove deposition by-products and films from
processing chamber hardware including the showerhead 118. The
process gases and/or cleaning agent may flow from the inlet 180 to
the process volume 112 through a plurality of gas passages 162
formed in the showerhead 118. A vacuum pump 119 is coupled to the
chamber 102 to facilitate negative pressure in the process volume
112 and exhaust of process gases from the process volume 112.
[0024] The showerhead 118 is typically fabricated from stainless
steel, aluminum (Al), anodized aluminum, nickel (Ni) or other
conductive material. The showerhead 118 may be supported in a
center region by a plurality of support members 123. Each of the
plurality of support members 123 may be adjustable fasteners
coupled to the backing plate 101 or through the backing plate 101
and coupled with a support assembly outside of the chamber 102 (not
shown).
[0025] The showerhead 118 typically may also include a flexible
support 160 adapted to allow for thermal expansion and contraction
of the perimeter of the showerhead 118. The plurality of gas
passages 162 are formed through the showerhead 118 to allow a
predetermined distribution of gas passing through the showerhead
118 and into the process volume 112. The flexible support 160 also
maintains the showerhead 118 in a spaced-apart relation relative to
the substrate support assembly 138.
[0026] In one embodiment, the backing plate support member 111 is
adapted to couple to the walls 106 by one or more fasteners 113.
The backing plate support member 111 is compressed against a seal
148 by compression provided by one or both of the fasteners 113 and
the sheer weight of the lid assembly 110. The lid assembly 110,
which includes the backing plate 101, provides an upper boundary to
the process volume 112 by sealing against the walls 106. In
particular, an interior surface 120 of the backing plate 101, at
least between a seal 114, provides the upper boundary to the
process volume 112.
[0027] The lid assembly 110 also includes a plurality of clamp
devices 117 disposed between the lid cover 105 and the backing
plate 101. Specifically, the clamp devices 117 provide compression
to the upper surface of the backing plate 101, which compresses the
backing plate 101 against the seal 114 to provide an upper boundary
for negative pressure within the chamber 102. While the seal 114 is
described as a pressure sealing member, the seal 114 may also be
adapted as an electrical insulator to insulate the backing plate
101 from the backing plate support member 111 and/or other portions
of the chamber 102. In one embodiment, the seal 114 is a polymer or
elastomer that provides a vacuum seal and additionally facilitates
electrical insulation.
[0028] FIG. 2 is an isometric view of on embodiment of a clamp
device 117. In this embodiment, the clamp device 117 comprises an
upper clamp portion 204 and a lower clamp portion 208. The upper
clamp portion 204 includes an opening 206 which allows a first
fastener 212, such as a screw, to couple the upper clamp portion
204 to the interior portion of a lid support 103 which is a portion
of the lid assembly 110. Alternatively, the upper clamp portion 204
may be attached to the lid support by adhesives or welding. In
another alternative, the upper clamp portion 204 may be an integral
part of the lid support 103, such as an extension or protrusion
disposed on the lid support 103. The upper clamp portion 204 is
adapted to be stationary or immovable relative to the lid support
103 while the lower clamp portion 208 is movable relative to the
lid support 103. In one embodiment, one or both of the lower clamp
portion 208 and the upper clamp portion 204 may be made of
polyetheretherketone (PEEK) material.
[0029] In one embodiment, the lower clamp portion 208 and the upper
clamp portion 204 are configured as wedges to provide a compressive
force to the backing plate 101. For example, the lower clamp
portion 208 and the upper clamp portion 204 include at least one
slanted or inclined surface adapted to provide a movable interface
therebetween. As the slanted surfaces move relative to each other
in at least one direction of travel, compression is applied to the
backing plate 101. In one embodiment, the lower clamp portion 208
includes a first slanted surface 218A and the upper clamp portion
204 includes a second slanted surface 218B. The slanted surfaces
218A, 218B of both the upper clamp 204 and lower clamp 208 are
adapted to be in sliding contact to vary compressive force to the
backing plate 101 as the clamp device 117 is adjusted.
[0030] FIG. 3 is a cross-sectional view of the clamp device 117 of
FIG. 2. The upper clamp portion 204 is configured to be immovable
relative to the lid support 103. The upper clamp portion 204 is
statically coupled to the lid support 103 by a first fastener 212,
such as a screw, inserted through a hole in the upper clamp portion
204 and tightened against a threaded portion formed in the lid
support 103. While only one fastener is used, it is understood that
more than one fastener may be used to couple the upper clamp
portion 204 with the lid support 103. A second fastener 214, such
as a bolt, may be inserted through aligned openings in the both of
the lower clamp portion 208 and the lid support 103. A rotatable
coupling, such as a nut 216 may be rotated onto an exposed threaded
portion of the second fastener 214. The nut 216 is exposed on the
exterior side of the lid support 103 and can be accessed by
personnel from the exterior of the chamber 102 without having to
disassemble the entire lid assembly 110, or at the minimum, remove
the lid cover 105 and any hardware disposed therethrough or
thereon.
[0031] In one embodiment, the second fastener 214 may be made of
stainless steel having a head 320 and a threaded end 330 opposite
the head 320. In another embodiment, the second fastener 214 may be
an Allen head bolt having a rotation prevention feature 325 in or
on the head 320 to minimize rotation of the second fastener 214
during adjustment of the nut 216. The rotation prevention feature
325 may be a flattened portion, a stop or a pin or protrusion
adjacent the head 320. In other embodiments, the rotation
prevention feature may be a slot adapted to receive a screw driving
device, a flattened portion disposed on an outer surface of the
head 320 adapted to mate with a corresponding flat or stop disposed
in the lower clamp portion 208, an orifice or depression adapted to
receive a tool, or other feature adapted to minimize rotation of
the Allen head bolt during adjustment of the nut 216. In yet
another embodiment, the second fastener 214 may include a hex head
bolt, a square head bolt, or other fastener. In one embodiment, the
nut 216 may be made of stainless steel with anti-bind/gall coating.
In yet another embodiment, the anti-bind/gall coating may be made
of tungsten disulfide (WS.sub.2) or dicronite.
[0032] Continued rotation or tightening of the nut 216 causes
lateral movement of the lower clamp portion 208 relative to the
upper clamp portion 204 and along a periphery of the backing plate
101. The lower clamp portion 208 includes a sliding contact surface
305 adapted to contact an upper surface 310 of the backing plate
101. As the lateral movement of the lower clamp portion 208
continues, contact between the first slanted surface 218A and the
second slanted surface 218B is established. When the first slanted
surface 218A and the second slanted surface 218B contact each
other, the lower clamp portion 208 provides a compressive force to
the upper surface 310 of the backing plate 101. Thus, the
compressive pressure provided to the upper surface 310 of the
backing plate 101 translates to compress a sealing surface 315 of
the backing plate 101 against the seal 114. In one embodiment, all
sliding contact surfaces may include a radius or bevel to minimize
one surface gouging or cutting into another as the surfaces move
relative to each other.
[0033] FIG. 4 is a cross-sectional view of one embodiment of a nut
216. The nut 216 includes a body 400 having threads 405 formed
therethrough. In one embodiment, the body is made of stainless
steel. In another embodiment, the body 400 may be made of stainless
steel and the threads 405 may include a coating 410 configured to
minimize binding with the second fastener 214. In one embodiment,
the coating 410 may be made of tungsten disulfide (WS.sub.2) or
dicronite.
[0034] While the weight of the backing plate 101 facilitates
contact with the seal 114 and may facilitate a vacuum-tight
interface by compression on the seal 114, the clamp devices 117
provide additional compression of the sealing surfaces of the
backing plate 101 against the seal 114. In one embodiment, the
clamp devices 117 are adapted to form an initial vacuum seal
between the backing plate 101 and the sealing surfaces. For
example, the weight of the backing plate 101 may provide
insufficient contact between the sealing surfaces of the backing
plate 101 and the seal 114. In this example, the clamp devices 117
may provide compression and facilitate vacuum sealing with
assistance from the vacuum pump 119, which pulls the interior
surface of the backing plate 101 toward the process volume 112
providing additional compressive force to the backing plate 101
against the seal 114. Once the initial vacuum seal has been
established, the clamp devices 117 may remain in compressive
contact with the backing plate 101 or even loosen to not be in
compressive contact with the backing plate 101, but the initial
vacuum seal may remain intact to withstand many vacuum applications
or processing cycles without readjustment of the clamp devices
117.
[0035] However, over time, the initial seal may be breached and the
clamp devices 117 may need to be readjusted to restore the vacuum
seal. For example, cyclic vacuum application and/or
expansive/contractive movement of the backing plate 101 relative to
the seal 114 may cause failure of the vacuum seal. Additionally, a
user may choose to periodically adjust the clamp devices 117 to
ensure compressive contact between the clamp devices 117 and the
backing plate 101 thereby maintaining the compressive contact and
the vacuum seal.
[0036] In another scenario, the lid assembly 110 may be
periodically separated from the walls 106 to access and/or service
interior portions of the processing chamber 102. The lid assembly
110 may be removed from the walls 106 by lifting the lid assembly
110 with a crane or other lifting device adapted to separate the
lid assembly 110 from the walls 106. As the lid assembly 110 is
removed or separated from the walls 106, components such as the
showerhead 118 may be accessed by personnel for cleaning,
inspection or other maintenance procedure. Additionally, in this
separated state, the lid cover 105 may be removed to access the
backing plate 101 for maintenance, inspection or other servicing
procedure.
[0037] After maintenance procedures have been performed, the lid
assembly 110 may be reassembled or otherwise readied for
re-attachment to the walls 106. As the lid assembly 110 is
reassembled, the upper clamp portions 204 of each of the clamp
devices 117 are statically coupled to an interior portion of the
lid assembly 110 by the first fastener 212 and the lower clamp 208
of each of the clamp devices 117 are positioned adjacent the upper
clamp 204 and the upper surface of the backing plate 101. The
second fastener 214 is inserted through the lower clamp portion 208
and lid support 103 and is tightened by the nut 216 to be snug. The
lid assembly 110 may be lifted by a crane and is positioned against
the walls 106. The lid assembly 110 is then secured to the walls
106 by fasteners 113. After the lid assembly 110 is suitably
coupled to the walls 106, personnel may tighten each of the nuts
216 of each of the clamp devices 117 to compress the backing plate
101 against the seal 114. The nuts 216 are exposed on the exterior
side of the lid support 103 and can be accessed from the exterior
without having to disassemble the entire lid assembly 110, or at
the minimum, remove the lid cover 105 (and any hardware disposed
therethrough or thereon). Thereafter, negative pressure may be
applied to the process volume 112 to perform a deposition
process.
[0038] As mentioned above, during multiple deposition processes,
the backing plate 101 may move relative to the seal 114, which may
breach the vacuum seal. Other vacuum breaches may occur due to
loosening of the clamp devices 117 and/or backing plate 101 by
causes or forces such as vibration, disassembly of portions of the
chamber 102, among other causes or forces. In one scenario, one or
more of the previously tight clamp devices 117 may be loosened due
to vacuum application to the backing plate 101, which may further
bind the backing plate against the seal 114 to a point where one or
more of the clamp devices 117 may not be in compressive contact
with the backing plate 101. The structure and location of the clamp
devices 117 as described herein provide a suitable remedy to
tighten the backing plate 101 against the seal 114.
[0039] In any of the situations discussed above, and other
situations requiring tightening of or providing additional
compression to the backing plate 101, the clamp devices 117 allow
adjustment by personnel from a location outside of the chamber 102.
Additionally, disassembly of portions of the chamber 102 is not
required to access the clamp devices 117 for adjustment. Thus,
downtime may be minimized and throughput of the chamber 102 may be
enhanced.
[0040] While the foregoing is directed to embodiments of the
present invention, other and further embodiments of the invention
may be devised without departing from the basic scope thereof, and
the scope thereof is determined by the claims that follow.
* * * * *