U.S. patent application number 13/210018 was filed with the patent office on 2011-12-08 for apparatuses and methods for conditioning polishing pads used in polishing micro-device workpieces.
This patent application is currently assigned to MICRON TECHNOLOGY, INC.. Invention is credited to Suresh Ramarajan.
Application Number | 20110300782 13/210018 |
Document ID | / |
Family ID | 32824555 |
Filed Date | 2011-12-08 |
United States Patent
Application |
20110300782 |
Kind Code |
A1 |
Ramarajan; Suresh |
December 8, 2011 |
APPARATUSES AND METHODS FOR CONDITIONING POLISHING PADS USED IN
POLISHING MICRO-DEVICE WORKPIECES
Abstract
Apparatuses and methods for conditioning polishing pads used in
polishing micro-device workpieces are disclosed herein. In one
embodiment, an end effector for conditioning a polishing pad
includes a member having a first surface and a plurality of contact
elements projecting from the first surface. The member also
includes a plurality of apertures configured to flow conditioning
solution to the polishing pad. The apertures can extend from the
first surface to a second surface opposite the first surface. The
member can further include a manifold that is in fluid
communication with the apertures. In another embodiment, a
conditioner for conditioning the polishing pad includes an arm
having at least one spray nozzle configured to spray conditioning
solution onto the polishing pad and an end effector coupled to the
arm. The end effector includes a first surface and a plurality of
contact elements projecting from the first surface.
Inventors: |
Ramarajan; Suresh; (Boise,
ID) |
Assignee: |
MICRON TECHNOLOGY, INC.
Boise
ID
|
Family ID: |
32824555 |
Appl. No.: |
13/210018 |
Filed: |
August 15, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12760180 |
Apr 14, 2010 |
7997958 |
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13210018 |
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11092157 |
Mar 28, 2005 |
7708622 |
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12760180 |
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10365086 |
Feb 11, 2003 |
6884152 |
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11092157 |
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Current U.S.
Class: |
451/56 ;
451/443 |
Current CPC
Class: |
B24B 37/04 20130101;
B24B 57/02 20130101 |
Class at
Publication: |
451/56 ;
451/443 |
International
Class: |
B24B 53/00 20060101
B24B053/00 |
Claims
1. A conditioner for conditioning a polishing pad used in polishing
a micro-device workpiece, comprising: an end effector including a
first surface and a plurality of contact elements projecting from
the first surface; and a spray nozzle proximate to the end
effector, the spray nozzle being configured to spray a conditioning
solution onto the polishing pad.
2. The conditioner of claim 1, further comprising an arm coupled to
the end effector, wherein the spray nozzle is coupled to the arm to
dispense the conditioning solution onto the polishing pad.
3. The conditioner of claim 1 wherein the spray nozzle is a first
spray nozzle configured to spray the conditioning solution in a
first direction, wherein the conditioner further comprises an arm
coupled to the end effector, the arm having a second spray nozzle
configured to spray the conditioning solution in a second direction
different than the first direction.
4. The conditioner of claim 1 wherein the spray nozzle is a first
spray nozzle configured to spray the conditioning solution at a
first mean radius, wherein the conditioner further comprises an arm
coupled to the end effector, the arm having a second spray nozzle
configured to spray the conditioning solution at a second mean
radius different than the first mean radius.
5. The conditioner of claim 1 wherein the end effector further
includes a second surface opposite the first surface, and wherein
the spray nozzle is coupled to the second surface.
6. A conditioner for conditioning a polishing pad used in polishing
a micro-device workpiece, comprising: an arm including at least one
spray nozzle configured to spray a conditioning solution onto the
polishing pad; and an end effector coupled to the arm, the end
effector including a first surface and a plurality of contact
elements projecting from the first surface.
7. The conditioner of claim 6 wherein the at least one spray nozzle
comprises a first spray nozzle configured to spray the conditioning
solution onto the polishing pad at a first mean radius and a second
spray nozzle configured to spray the conditioning solution onto the
polishing pad at a second mean radius different than the first mean
radius.
8. The conditioner of claim 6 wherein the at least one spray nozzle
comprises a first spray nozzle configured to spray the conditioning
solution onto the polishing pad in a first direction and a second
spray nozzle configured to spray the conditioning solution onto the
polishing pad in a second direction different than the first
direction.
9. The conditioner of claim 6 wherein the arm is configured to
sweep the end effector across the polishing pad, and wherein the at
least one spray nozzle is configured to dispense the conditioning
solution across the polishing pad.
10. An apparatus for conditioning a polishing pad used in polishing
micro-device workpieces, comprising: a table having a support
surface; a polishing pad coupled to the support surface of the
table; a source of conditioning solution; and a conditioner
including an end effector, a spray nozzle proximate to the end
effector, and a drive system coupled to the end effector, the end
effector having a first surface and a plurality of contact elements
projecting from the first surface, wherein the spray nozzle is
operatively coupled to the source of conditioning solution and
configured to spray a conditioning solution onto the polishing pad,
and wherein the conditioner and/or the table is movable relative to
the other to rub the plurality of contact elements against the
polishing pad.
11. The apparatus of claim 10 wherein the conditioner further
includes an arm coupled to the end effector, and wherein the spray
nozzle is coupled to the arm to dispense the conditioning solution
onto the polishing pad.
12. The apparatus of claim 10 wherein the end effector further
includes a second surface opposite the first surface, and wherein
the spray nozzle is coupled to the second surface.
13. An apparatus for conditioning a polishing pad used in polishing
micro-device workpieces, comprising: a table having a support
surface; a polishing pad coupled to the support surface of the
table; a source of conditioning solution; and a conditioner
including an arm, an end effector coupled to the arm, and a drive
system coupled to the arm, the arm having at least one spray nozzle
operatively coupled to the source of conditioning solution and
configured to spray a conditioning solution onto the polishing pad,
the end effector having a first surface and a plurality of contact
elements projecting from the first surface, wherein the conditioner
and/or the table is movable relative to the other to rub the
plurality of contact elements against the polishing pad.
14. The apparatus of claim 13 wherein the at least one spray nozzle
includes a first spray nozzle configured to spray the conditioning
solution onto the polishing pad at a first mean radius and a second
spray nozzle configured to spray the conditioning solution onto the
polishing pad at a second mean radius different than the first mean
radius.
15. The apparatus of claim 13 wherein the at least one spray nozzle
includes a first spray nozzle configured to spray in a first
direction and a second spray nozzle configured to spray in a second
direction different than the first direction.
16. The apparatus of claim 13 wherein the arm is configured to
sweep the end effector across the polishing pad, and wherein the at
least one spray nozzle is configured to dispense the conditioning
solution across the polishing pad.
17. An apparatus for conditioning a polishing pad used in polishing
micro-device workpieces, comprising: a table having a support
surface; a polishing pad coupled to the support surface of the
table; a source of conditioning solution; a micro-device workpiece
carrier including a spray nozzle operatively coupled to the source
of conditioning solution by a fluid line and configured to flow a
conditioning solution onto the polishing pad during conditioning;
and a conditioner including an end effector and a drive system
coupled to the end effector, the end effector having a first
surface and a plurality of contact elements projecting from the
first surface, wherein the conditioner and/or the table is movable
relative to the other to rub the plurality of contact elements
against the polishing pad.
18. The apparatus of claim 17 wherein the micro-device workpiece
carrier is movable to flow the conditioning solution across the
polishing pad.
19. The apparatus of claim 17 wherein the micro-device workpiece
carrier is movable with the conditioner to flow conditioning
solution onto the polishing pad proximate to the conditioner.
20. An apparatus for conditioning a polishing pad used in polishing
micro-device workpieces, comprising: a table having a support
surface; a polishing pad coupled to the support surface of the
table; a fluid arm positioned proximate to the polishing pad, the
fluid arm having a first spray nozzle, a second spray nozzle, and a
fluid manifold in fluid communication with the first and second
spray nozzles, wherein the first spray nozzle is configured to flow
a conditioning solution onto the polishing pad at a first mean
radius, and wherein the second spray nozzle is configured to flow
the conditioning solution onto the polishing pad at a second mean
radius different from the first mean radius; and a conditioner
including an end effector and a drive system coupled to the end
effector, the end effector having a first surface and a plurality
of contact elements projecting from the first surface, wherein the
conditioner and/or the table is movable relative to the other to
rub the plurality of contact elements against the polishing
pad.
21. The apparatus of claim 20 wherein the first spray nozzle is
configured to flow the conditioning solution at a first flow rate
and the second spray nozzle is configured to flow the conditioning
solution at a second flow rate different from the first flow
rate.
22. An apparatus for conditioning a planarizing surface of a
polishing pad, comprising: a source of conditioning solution; an
arm; an end effector carried by the arm, the end effector having a
contact surface and a plurality of abrasive elements projecting
from the contact surface; and a fluid dispenser on the arm and/or
the end effector, the fluid dispensor being operatively coupled to
the source of conditioning solution by a fluid line.
23. The apparatus of claim 22 wherein the fluid dispenser comprises
an aperture in the contact surface of the end effector.
24. The apparatus of claim 22 wherein the fluid dispenser comprises
a spray nozzle on the arm and/or the end effector.
25. The apparatus of claim 22 wherein the fluid dispenser is
configured to dispense conditioning solution onto the polishing pad
proximate to the end effector.
26. A method for conditioning a polishing pad used in polishing a
micro-device workpiece, comprising: rubbing a plurality of contact
elements on a surface of an end effector against a planarizing
surface of the polishing pad; and flowing a conditioning solution
through apertures in the end effector and onto the planarizing
surface of the polishing pad.
27. The method of claim 26 wherein flowing the conditioning
solution comprises disposing the conditioning solution between the
surface of the end effector and the polishing pad.
28. The method of claim 26 wherein flowing the conditioning
solution comprises: disposing a first volume of conditioning
solution between the polishing pad and the surface of the end
effector at a first radius on the polishing pad; and disposing a
second volume of conditioning solution between the polishing pad
and the surface of the end effector at a second radius different
from the first radius on the polishing pad, wherein the second
volume is at least approximately equal to the first volume.
29. The method of claim 26 wherein flowing the conditioning
solution comprises: disposing conditioning solution having a first
concentration of active chemicals between the polishing pad and the
surface of the end effector at a first radius on the polishing pad;
and disposing conditioning solution having a second concentration
of active chemicals between the polishing pad and the surface of
the end effector at a second radius different from the first radius
on the polishing pad, wherein the second concentration is at least
approximately equal to the first concentration.
30. The method of claim 26 wherein flowing the conditioning
solution comprises passing the conditioning solution through a
manifold in the end effector.
31. The method of claim 26 wherein flowing the conditioning
solution comprises passing the conditioning solution through
apertures in the surface of the end effector.
32. The method of claim 26, further comprising dispensing
conditioning solution from a spray nozzle on an arm coupled to the
end effector.
33. A method for conditioning a polishing pad used in polishing a
micro-device workpiece, comprising: rubbing a plurality of contact
elements of an end effector of a conditioner against a planarizing
surface of the polishing pad; and flowing a conditioning solution
through a spray nozzle of the conditioner and onto the planarizing
surface of the polishing pad.
34. The method of claim 33 wherein flowing the conditioning
solution comprises: disposing a first volume of conditioning
solution between the polishing pad and the end effector at a first
radius on the polishing pad; and disposing a second volume of
conditioning solution between the polishing pad and the end
effector at a second radius different than the first radius on the
polishing pad, wherein the second volume is at least approximately
equal to the first volume.
35. The method of claim 33 wherein flowing the conditioning
solution comprises: disposing conditioning solution having a first
concentration of active chemicals between the polishing pad and the
end effector at a first radius on the polishing pad; and disposing
conditioning solution having a second concentration of active
chemicals between the polishing pad and the end effector at a
second radius different than the first radius of the polishing pad,
wherein the second concentration is at least approximately equal to
the first concentration.
36. The method of claim 33 wherein flowing the conditioning
solution comprises disposing the conditioning solution between the
end effector and the polishing pad.
37. The method of claim 33 wherein the spray nozzle is a first
spray nozzle, and wherein flowing the conditioning solution
comprises: flowing the conditioning solution through the first
spray nozzle and onto the polishing pad at a first mean radius; and
flowing the conditioning solution through a second spray nozzle and
onto the polishing pad at a second mean radius different than the
first mean radius.
38. The method of claim 33 wherein the spray nozzle is a first
spray nozzle, and wherein flowing the conditioning solution
comprises: flowing the conditioning solution through the first
spray nozzle in a first direction; and flowing the conditioning
solution through the second spray nozzle in a second direction
different than the first direction.
39. A method for conditioning a polishing pad used in polishing a
micro-device workpiece, comprising: rubbing a plurality of contact
elements of an end effector against a planarizing surface of the
polishing pad; and flowing a conditioning solution through a spray
nozzle of a micro-device workpiece carrier and onto the planarizing
surface of the polishing pad.
40. The method of claim 39 wherein flowing the conditioning
solution comprises sweeping the micro-device workpiece carrier
across the polishing pad to dispense conditioning solution across
the polishing pad.
41. The method of claim 39 wherein flowing the conditioning
solution comprises: disposing a first volume of conditioning
solution between the polishing pad and the end effector at a first
radius on the polishing pad; and disposing a second volume of
conditioning solution between the polishing pad and the end
effector at a second radius different than the first radius on the
polishing pad, wherein the second volume is at least approximately
equal to the first volume.
42. The method of claim 39 wherein flowing the conditioning
solution comprises: disposing conditioning solution having a first
concentration of active chemicals between the polishing pad and the
end effector at a first radius on the polishing pad; and disposing
conditioning solution having a second concentration of active
chemicals between the polishing pad and the end effector at a
second radius different than the first radius on the polishing pad,
wherein the second concentration is at least approximately equal to
the first concentration.
43. The method of claim 39 wherein flowing the conditioning
solution comprises disposing the conditioning solution between the
end effector and the polishing pad.
44. A method for conditioning a polishing pad used in polishing a
micro-device workpiece, comprising: rubbing a plurality of contact
elements of an end effector against a planarizing surface of the
polishing pad; flowing conditioning solution through a first spray
nozzle of a fluid arm and onto a planarizing surface of the
polishing pad at a first mean radius; and flowing conditioning
solution through a second spray nozzle of the fluid arm and onto
the planarizing surface of the polishing pad at a second mean
radius different than the first mean radius.
45. The method of claim 44 wherein: flowing the conditioning
solution through the first spray nozzle comprises disposing a first
volume of conditioning solution between the polishing pad and the
end effector at a first radius on the polishing pad; and flowing
the conditioning solution through the second spray nozzle comprises
disposing a second volume of conditioning solution between the
polishing pad and the end effector at a second radius different
than the first radius on the polishing pad, wherein the second
volume is at least approximately equal to the first volume.
46. The method of claim 44 wherein: flowing the conditioning
solution through the first spray nozzle comprises disposing
conditioning solution having a first concentration of active
chemicals between the polishing pad and the end effector at a first
radius on the polishing pad; and flowing the conditioning solution
through the second spray nozzle comprises disposing conditioning
solution having a second concentration of active chemicals between
the polishing pad and the end effector at a second radius different
than the first radius on the polishing pad, wherein the second
concentration is at least approximately equal to the first
concentration.
47. A method for conditioning a polishing pad used in polishing a
micro-device workpiece, comprising: disposing a first volume of
conditioning solution between the polishing pad and an end effector
at a first radius proximate to a center of the polishing pad; and
disposing a second volume of conditioning solution between the
polishing pad and the end effector at a second radius proximate to
a perimeter of the polishing pad, wherein the second volume is at
least approximately equal to the first volume.
48. The method of claim 47 wherein disposing the first volume of
conditioning solution comprises flowing the conditioning solution
through apertures in the end effector.
49. The method of claim 47 wherein disposing the first volume of
conditioning solution comprises flowing the conditioning solution
through a spray nozzle proximate to the end effector.
50. The method of claim 47 wherein disposing the first volume of
conditioning solution comprises flowing the conditioning solution
through a spray nozzle coupled to a micro-device workpiece
carrier.
51. A method for conditioning a polishing pad used in polishing a
micro-device workpiece, comprising: disposing conditioning solution
having a first concentration of active chemicals between the
polishing pad and an end effector at a first radius proximate to a
center of the polishing pad; and disposing conditioning solution
having a second concentration of active chemicals between the
polishing pad and the end effector at a second radius proximate to
a perimeter of the polishing pad, wherein the second concentration
is at least approximately equal to the first concentration.
52. The method of claim 51 wherein disposing conditioning solution
having the first concentration comprises flowing conditioning
solution through apertures in the end effector.
53. The method of claim 51 wherein disposing conditioning solution
having the first concentration comprises flowing conditioning
solution through a spray nozzle proximate to the end effector.
54. The method of claim 51 wherein disposing conditioning solution
having the first concentration comprises flowing conditioning
solution through a spray nozzle coupled to a micro-device workpiece
carrier.
55. A method for conditioning a polishing pad used in polishing a
micro-device workpiece, comprising: rubbing a plurality of contact
elements of an end effector carried by an arm against a planarizing
surface of the polishing pad; and flowing a conditioning solution
through a fluid dispenser on the arm and/or the end effector.
56. The method of claim 55 wherein flowing the conditioning
solution comprises passing the conditioning solution through a
spray nozzle and onto the polishing pad.
57. The method of claim 55 wherein flowing the conditioning
solution comprises passing the conditioning solution through
apertures in the end effector.
58. The method of claim 55, further comprising sweeping the end
effector across the polishing pad and dispensing the conditioning
solution across the polishing pad.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. application Ser.
No. 12/760,180 filed Apr. 14, 2010, now U.S. Pat. No. 7,997,958,
which is a divisional of U.S. application Ser. No. 11/092,157 filed
Mar. 28, 2005, now U.S. Pat. No. 7,708,622, which is a divisional
of U.S. application Ser. No. 10/365,086 filed Feb. 11, 2003, now
U.S. Pat. No. 6,884,152, each of which is incorporated herein by
reference.
TECHNICAL FIELD
[0002] The present invention relates to apparatuses and methods for
conditioning polishing pads used in polishing micro-device
workpieces.
BACKGROUND
[0003] Mechanical and chemical-mechanical planarization processes
(collectively "CMP") remove material from the surface of
micro-device workpieces in the production of microelectronic
devices and other products. FIG. 1 schematically illustrates a
rotary CMP machine 10 with a platen 20, a carrier head 30, and a
planarizing pad 40. The CMP machine 10 may also have an under-pad
25 between an upper surface 22 of the platen 20 and a lower surface
of the planarizing pad 40. A drive assembly 26 rotates the platen
20 (indicated by arrow F) and/or reciprocates the platen 20 back
and forth (indicated by arrow G). Since the planarizing pad 40 is
attached to the under-pad 25, the planarizing pad 40 moves with the
platen 20 during planarization.
[0004] The carrier head 30 has a lower surface 32 to which a
micro-device workpiece 12 may be attached, or the workpiece 12 may
be attached to a resilient pad 34 under the lower surface 32. The
carrier head 30 may be a weighted, free-floating wafer carrier, or
an actuator assembly 36 may be attached to the carrier head 30 to
impart rotational motion to the micro-device workpiece 12
(indicated by arrow J) and/or reciprocate the workpiece 12 back and
forth (indicated by arrow I).
[0005] The planarizing pad 40 and a planarizing solution 44 define
a planarizing medium that mechanically and/or
chemically-mechanically removes material from the surface of the
micro-device workpiece 12. The planarizing solution 44 may be a
conventional CMP slurry with abrasive particles and chemicals that
etch and/or oxidize the surface of the micro-device workpiece 12,
or the planarizing solution 44 may be a "clean" nonabrasive
planarizing solution without abrasive particles. In most CMP
applications, abrasive slurries with abrasive particles are used on
nonabrasive polishing pads, and clean nonabrasive solutions without
abrasive particles are used on fixed-abrasive polishing pads.
[0006] To planarize the micro-device workpiece 12 with the CMP
machine 10, the carrier head 30 presses the workpiece 12 face-down
against the planarizing pad 40. More specifically, the carrier head
30 generally presses the micro-device workpiece 12 against the
planarizing solution 44 on a planarizing surface 42 of the
planarizing pad 40, and the platen 20 and/or the carrier head 30
moves to rub the workpiece 12 against the planarizing surface 42.
As the micro-device workpiece 12 rubs against the planarizing
surface 42, the planarizing medium removes material from the face
of the workpiece 12.
[0007] The CMP process must consistently and accurately produce a
uniformly planar surface on the micro-device workpiece 12 to enable
precise fabrication of circuits and photo-patterns. One problem
with conventional CMP methods is that the planarizing surface 42 of
the planarizing pad 40 can wear unevenly, causing the pad 40 to
have a non-planar planarizing surface 42. Another concern is that
the surface texture of the planarizing pad 40 may change
non-uniformly over time. Still another problem with CMP processing
is that the planarizing surface 42 can become glazed with
accumulations of planarizing solution 44, material removed from the
micro-device workpiece 12, and/or material from the planarizing pad
40.
[0008] To restore the planarizing characteristics of the
planarizing pad 40, the accumulations of waste matter are typically
removed by conditioning the planarizing pad 40. Conditioning
involves delivering a conditioning solution to chemically remove
waste material from the planarizing pad 40 and moving a conditioner
50 across the pad 40. The conventional conditioner 50 includes an
abrasive end effector 51 generally embedded with diamond particles
and a separate actuator 55 coupled to the end effector 51 to move
it rotationally, laterally, and/or axially, as indicated by arrows
A, B, and C, respectively. The typical end effector 51 removes a
thin layer of the planarizing pad material in addition to the waste
matter to form a more planar, clean planarizing surface 42 on the
planarizing pad 40.
[0009] One drawback of conventional methods for conditioning
planarizing pads is that waste material may not be completely
removed from the pad because the conditioning solution is not
uniformly distributed across the pad, and thus, the waste material
may not be completely removed from the pad. Typically, the
conditioning solution is delivered at a fixed location near the
center of the planarizing pad and moves radially outward due to the
centrifugal force caused by the rotating pad. As a result, the
region of the pad radially inward from the delivery point does not
receive the conditioning solution. Moreover, the concentration of
active chemicals in the conditioning solution decreases as the
solution moves toward the perimeter of the pad. The centrifugal
force also may not distribute the conditioning solution uniformly
across the pad. Accordingly, there is a need to improve the
conventional conditioning systems.
SUMMARY
[0010] The present invention is directed to apparatuses and methods
for conditioning polishing pads used in polishing micro-device
workpieces. In one embodiment, an end effector for conditioning a
polishing pad includes a member having a first surface and a
plurality of contact elements projecting from the first surface.
The member also includes a plurality of apertures configured to
flow a conditioning solution onto the polishing pad. In one aspect
of this embodiment, the apertures can extend from the first surface
to a second surface opposite the first surface. The apertures can
also be arranged in a generally uniform pattern. In another aspect
of this embodiment, the member further includes a manifold in fluid
communication with the apertures.
[0011] In another embodiment of the invention, a conditioner for
conditioning the polishing pad includes an arm having at least one
spray nozzle configured to spray a conditioning solution onto the
polishing pad and an end effector coupled to the arm. The end
effector includes a first surface and a plurality of contact
elements projecting from the first surface. In one aspect of this
embodiment, the spray nozzle can be a first spray nozzle configured
to spray conditioning solution onto the polishing pad at a first
mean radius, and the conditioner can further include a second spray
nozzle configured to spray conditioning solution onto the polishing
pad at a second mean radius. In another aspect of this embodiment,
the arm is configured to sweep the end effector across the
polishing pad to dispense conditioning solution across the pad. The
conditioner and/or the polishing pad is movable relative to the
other to rub the plurality of contact elements against the pad.
[0012] In an additional embodiment of the invention, an apparatus
for conditioning the polishing pad includes a table having a
support surface, a polishing pad coupled to the support surface of
the table, a source of conditioning solution, a micro-device
workpiece carrier, and a conditioner. The micro-device workpiece
carrier includes a spray nozzle that is operatively coupled to the
source of conditioning solution by a fluid line and configured to
flow a conditioning solution onto the polishing pad during
conditioning. The conditioner includes an end effector and a drive
system coupled to the end effector. The end effector has a first
surface and a plurality of contact elements projecting from the
first surface. The conditioner and/or the table is movable relative
to the other to rub the plurality of contact elements against the
polishing pad. In one aspect of this embodiment, the micro-device
workpiece carrier can be configured to sweep across the polishing
pad for uniform delivery of the conditioning solution.
[0013] In another embodiment of the invention, an apparatus for
conditioning the polishing pad includes a source of conditioning
solution, an arm, an end effector carried by the arm, and a fluid
dispenser on the arm and/or the end effector. The end effector has
a contact surface and a plurality of abrasive elements projecting
from the contact surface. The fluid dispenser is operatively
coupled to the source of conditioning solution by a fluid line. The
fluid dispenser can comprise an aperture in the contact surface of
the end effector and/or a spray nozzle on the arm and/or the end
effector.
[0014] In another embodiment of the invention, an apparatus for
conditioning the polishing pad includes a table having a support
surface, a polishing pad coupled to the support surface of the
table, a fluid arm positioned proximate to the polishing pad, and a
conditioner. The fluid arm has a first spray nozzle, a second spray
nozzle, and a fluid manifold that delivers fluid to the spray
nozzles. The first spray nozzle is configured to flow a
conditioning solution onto the polishing pad at a first mean
radius, and the second spray nozzle is configured to flow the
conditioning solution onto the polishing pad at a second mean
radius different from the first mean radius. The conditioner
includes an end effector and a drive system coupled to the end
effector. The end effector has a first surface and a plurality of
contact elements projecting from the first surface. The conditioner
and/or the table is movable relative to the other to rub the
plurality of contact elements against the polishing pad.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a schematic cross-sectional view of a portion of a
rotary planarizing machine and an abrasive end effector in
accordance with the prior art.
[0016] FIG. 2A is a bottom isometric view of a conditioner in
accordance with one embodiment of the invention.
[0017] FIG. 2B is a schematic side view of the conditioner of FIG.
2A in operation on a planarizing pad.
[0018] FIG. 3 is a schematic side view of a conditioner having an
end effector in accordance with another embodiment of the
invention.
[0019] FIG. 4 is a bottom view of an end effector in accordance
with another embodiment of the invention.
[0020] FIG. 5 is a schematic isometric view of a conditioner having
a spray nozzle in accordance with another embodiment of the
invention.
[0021] FIG. 6 is a schematic isometric view of a conditioning
system including a conditioner and a fluid arm in accordance with
another embodiment of the invention.
[0022] FIG. 7 is a schematic side view of a CMP machine and a
conditioner in accordance with another embodiment of the
invention.
[0023] FIG. 8 is a schematic isometric view of a conditioner in
accordance with another embodiment of the invention.
DETAILED DESCRIPTION
[0024] The present invention is directed toward apparatuses and
methods for conditioning polishing pads used in polishing
micro-device workpieces. The term "micro-device workpiece" is used
throughout to include substrates in and/or on which microelectronic
devices, micro-mechanical devices, data storage elements, and other
features are fabricated. For example, micro-device workpieces can
be semiconductor wafers, glass substrates, insulated substrates, or
many other types of substrates. Furthermore, the terms
"planarizing" and "planarization" mean either forming a planar
surface and/or forming a smooth surface (e.g., "polishing").
Several specific details of the invention are set forth in the
following description and in FIGS. 2A-8 to provide a thorough
understanding of certain embodiments of the invention. One skilled
in the art, however, will understand that the present invention may
have additional embodiments, or that other embodiments of the
invention may be practiced without several of the specific features
explained in the following description.
[0025] FIG. 2A is a bottom isometric view of a conditioner 150 in
accordance with one embodiment of the invention. The conditioner
150 can be coupled to a CMP machine, such as the CMP machine 10
discussed above with reference to FIG. 1. The conditioner 150
includes an end effector 151 for refurbishing the planarizing pad
on the CMP machine to bring the planarizing surface of the pad to a
desired state for consistent performance.
[0026] In the illustrated embodiment, the end effector 151 includes
a plate 152 and a plurality of contact elements 160 projecting from
the plate 152. The plate 152 can be a circular member having a
contact surface 154 configured to contact the planarizing surface
of the planarizing pad. The contact elements 160 can be integral
portions of the plate 152 or discrete elements such as bristles
coupled to the plate 152. In the illustrated embodiment, the
contact elements 160 are small diamonds attached to the contact
surface 154 of the plate 152.
[0027] FIG. 2B is a schematic side view of the conditioner 150 of
FIG. 2A and a planarizing pad 140. Referring to FIGS. 2A and 2B,
the end effector 151 also includes a plurality of apertures 170 in
the contact surface 154. In the illustrated embodiment, the
apertures 170 extend between the contact surface 154 and an upper
surface 156 opposite the contact surface 154. The conditioner 150
can also have a fitting 171 coupled to each aperture 170 and hoses
or lines 172 coupled to the fittings 171 (FIG. 2B). The apertures
170 can be fluid dispensers receiving a flow of conditioning
solution 143 (FIG. 2B) from the lines 172 and distributing the
conditioning solution 143 to a planarizing surface 142 of the
planarizing pad 140 during conditioning. The apertures 170 can be
arranged in a generally uniform pattern on the contact surface 154
to create a generally uniform distribution of conditioning solution
143 across the portion of the planarizing surface 142 proximate to
the contact surface 154 of the end effector 151. In other
embodiments, such as the embodiment described below with reference
to FIG. 4, the apertures can be arranged in a different pattern
and/or can have different sizes. In additional embodiments, such as
the embodiment described below with reference to FIG. 3, the
apertures may not extend between the contact surface 154 and the
upper surface 156.
[0028] In operation, the apertures 170 are coupled to a
conditioning solution supply source 173 (shown schematically in
FIG. 2B) by the fittings 171 and lines 172 to distribute the
conditioning solution 143 to the interface between the contact
surface 154 of the end effector 151 and the planarizing surface 142
of the planarizing pad 140. More specifically, as the end effector
151 rotates, the conditioning solution 143 flows through the
apertures 170 and onto the planarizing surface 142 of the
planarizing pad 140 to remove waste material from the pad 140.
[0029] The conditioning solution is selected to be compatible with
the planarizing pad material and enhance the removal of waste
material on the planarizing surface. The conditioning solution
typically dissolves the waste material, lubricates the interface
between the end effector and the pad, and/or weakens the adhesion
between the waste material and the pad. For example, in one
embodiment, a suitable conditioning solution for removing copper
waste material, such as copper oxide or copper chelates, from a
planarizing pad is ammonium citrate manufactured by Air Liquide
American L.P. of Houston, Tex., under the product number MD521. In
other embodiments, other suitable conditioning solutions can be
used.
[0030] One advantage of the embodiment illustrated in FIGS. 2A and
2B is that the apertures 170 provide a uniform distribution of
conditioning solution 143 between the end effector 151 and the
planarizing pad 140 as the conditioner 150 moves across the
planarizing pad 140. Furthermore, the concentration of active
chemicals in the conditioning solution 143 between the end effector
151 and the planarizing pad 140 is approximately the same at any
position on the planarizing pad 140. Another advantage of the
illustrated embodiment is that the apertures 170 provide
conditioning solution 143 to the interface between the end effector
151 and the planarizing pad 140 when the conditioner 150 conditions
the planarizing pad 140 including the center and the perimeter of
the pad 140.
[0031] FIG. 3 is a schematic side view of a conditioner 250 having
an end effector 251 and an arm 280 coupled to the end effector 251
in accordance with another embodiment of the invention. The end
effector 251 includes a plate 252 and contact elements 160
projecting from the plate 252. The plate 252 includes a contact
surface 254 having apertures 270, an upper surface 256, and a
manifold 274 between the upper surface 256 and the contact surface
254. The manifold 274 delivers the conditioning solution 143
through the apertures 270 to the planarizing surface 142 of the
planarizing pad 140. In the illustrated embodiment, the manifold
274 includes an inlet 276 coupled to a conditioning solution supply
conduit 281 extending through the arm 280.
[0032] FIG. 4 is a bottom view of an end effector 351 in accordance
with another embodiment of the invention. The end effector 351
includes a contact surface 354 and a plurality of contact elements
160 projecting from the contact surface 354. The end effector 351
also includes a plurality of first apertures 370a arranged within a
first region 371a of the contact surface 354 and a plurality of
second apertures 370b arranged within a second region 371b of the
contact surface 354. The first apertures 370a are configured to
provide a first volume of conditioning solution to the portion of
the planarizing pad proximate to the first region 371a of the
contact surface 354. The second apertures 370b are configured to
provide a second volume of conditioning solution to the portion of
the planarizing pad proximate to the second region 371b of the
contact surface 354. The second volume of conditioning solution is
less than the first volume because the second region 371b has a
smaller area than the first region 371a. To provide a greater
volume of conditioning solution, the first apertures 370a can have
a greater diameter or flow rate than the second apertures 370b, or
the end effector 351 can have a greater number of first apertures
370a than second apertures 370b. Accordingly, the first and second
apertures 370a-b provide a generally uniform distribution of
conditioning solution across the planarizing pad proximate to the
contact surface 354 during conditioning.
[0033] FIG. 5 is a schematic isometric view of a conditioner 450
having a spray nozzle 490 in accordance with another embodiment of
the invention. The conditioner 450 includes an end effector 451, an
arm 480 coupled to the end effector 451, and fluid dispensers such
as spray nozzles (identified individual as 490a-b) coupled to the
arm 480 and/or the end effector 451. In the illustrated embodiment,
the conditioner 450 moves laterally in the direction B across the
planarizing pad 140, and the spray nozzle 490a is configured to
spray conditioning solution 143 in the direction B onto a portion
of the planarizing pad 140 proximate to the end effector 451.
Accordingly, the spray nozzles 490 spray conditioning solution 143
onto a portion of the planarizing pad 140 before the end effector
451 conditions the portion of the pad 140. In one embodiment, the
arm 480 includes an internal actuator that rotates the end effector
451 in the direction A, thus enabling the spray nozzle 490a to be
aimed in the direction of the leading edge of the conditioner
450.
[0034] FIG. 6 is a schematic isometric view of a conditioning
system 500 including a conditioner 550 and a fluid arm 592 in
accordance with another embodiment of the invention. The
conditioner 550 includes an end effector 451 and an arm 580 coupled
to the end effector 451 to move the end effector 451 across the
planarizing pad 140. The fluid arm 592 extends radially from the
center of the planarizing pad 140 to the perimeter. The fluid arm
592 includes a plurality of spray nozzles (identified individually
as 590a-g). Each spray nozzle 590 is configured to spray
conditioning solution 143 at a specific mean radius of the
planarizing pad 140. For example, the first spray nozzle 590a is
configured to spray conditioning solution 143 at a first mean
radius R.sub.1 of the planarizing pad 140 and a second spray nozzle
590b is configured to spray conditioning solution 143 at a second
mean radius R.sub.2 different than the first mean radius R.sub.1 of
the planarizing pad 140. Similarly, the other spray nozzles 590
spray conditioning solution 143 onto the planarizing pad 140 at
different mean radii. In one embodiment, the spray nozzles 590 near
the perimeter of the planarizing pad 140 spray a greater volume of
conditioning solution 143 to cover the correspondingly greater
areas of the pad 140. Accordingly, the conditioning system 500 can
provide conditioning solution 143 with a uniform distribution and a
consistent concentration of active chemicals across the planarizing
pad 140. In other embodiments, the fluid arm 592 can include a
different number of spray nozzles 590, and/or the arm 592 can be
movable relative to the planarizing pad 140.
[0035] FIG. 7 is a schematic side view of a CMP machine 610 and a
conditioner 650 in accordance with another embodiment of the
invention. The CMP machine 610 can be generally similar to the CMP
machine 10 described above with reference to FIG. 1. For example,
the CMP machine 610 can include a planarizing pad 140 and a
micro-device workpiece carrier 630 having a lower surface 632 to
which a micro-device workpiece is attached. The micro-device
workpiece carrier 630 also includes a plurality of spray nozzles
690 coupled to a side surface 633. The spray nozzles 690 are
coupled to the conditioning solution source 173 to spray
conditioning solution 143 across the planarizing surface 142 of the
planarizing pad 140 during conditioning. In one embodiment, the
micro-device workpiece carrier 630 is spaced apart from the
planarizing pad 140 and moves around the pad 140 with the
conditioner 650 to provide conditioning solution 143 to portions of
the planarizing pad 140 proximate to the end effector 451. In
another embodiment, the micro-device workpiece carrier 630 moves
radially across the planarizing pad 140. In any of these
embodiments, the spray nozzles 690 on the micro-device workpiece
carrier 630 provide a uniform distribution of conditioning solution
143 and a consistent concentration of active chemicals in the
conditioning solution 143 to the interface between the end effector
451 and the planarizing pad 140 as the conditioner 650 moves across
the pad 140.
[0036] FIG. 8 is a schematic isometric view of a conditioner 750 in
accordance with another embodiment of the invention. The
conditioner 750 includes an end effector 451, a first arm 780a
coupled to the end effector 451, and a second arm 780b coupled to
the first arm 780a. The first and second arms 780a-b move the end
effector 451 across the planarizing pad 140. More specifically, the
first arm 780a rotates the end effector 451 in the direction A and
the second arm 780b sweeps the end effector 451 across the
planarizing pad 140 in the direction B. The first and second arms
780a-b can include a plurality of spray nozzles (identified
individually as 790a-d) to spray conditioning solution 143 across
the planarizing pad 140. The first, second, and third spray nozzles
790a-c are configured to spray conditioning solution 143 in a first
direction generally perpendicular to the planarizing pad 140. A
fourth spray nozzle 790d is configured to spray conditioning
solution 143 in a second direction generally parallel to the
planarizing pad 140. In additional embodiments, the first and
second arms 780a-b can have a different number of spray nozzles
790, and the spray nozzles 790 can be oriented in different
directions.
[0037] From the foregoing, it will be appreciated that specific
embodiments of the invention have been described herein for
purposes of illustration, but that various modifications may be
made without deviating from the spirit and scope of the invention.
Accordingly, the invention is not limited except as by the appended
claims.
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