US20020164926A1 - Retainer ring and method for polishing a workpiece - Google Patents
Retainer ring and method for polishing a workpiece Download PDFInfo
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- US20020164926A1 US20020164926A1 US09/850,578 US85057801A US2002164926A1 US 20020164926 A1 US20020164926 A1 US 20020164926A1 US 85057801 A US85057801 A US 85057801A US 2002164926 A1 US2002164926 A1 US 2002164926A1
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- 229920004943 Delrin® Polymers 0.000 description 1
- -1 Polytetrafluoroethylene Polymers 0.000 description 1
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 description 1
- 229920006362 Teflon® Polymers 0.000 description 1
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Images
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B37/00—Lapping machines or devices; Accessories
- B24B37/27—Work carriers
- B24B37/30—Work carriers for single side lapping of plane surfaces
- B24B37/32—Retaining rings
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
- Mechanical Treatment Of Semiconductor (AREA)
Abstract
A chemical mechanical polishing (CMP) machine (20) includes a workpiece carrier assembly (22) having a carrier base (24) with a workpiece contacting side (26) for holding a first surface (30) of a workpiece (32). A method utilizing the CMP machine (20) to polish the workpiece (32) and achieve a minimal edge exclusion region (92) entails adapting the carrier base (24) to reduce a first diameter (53) of a workpiece contacting side (26) of the carrier base (24) to a second diameter (84). The method further calls for providing a retainer ring (68, 106) disposed concentrically on the carrier base (24) for retaining the workpiece (32), and applying pressure on the carrier base (24) to urge a second surface (34) of the workpiece (36) against a polishing pad (36) of the CMP machine (20). In a first embodiment, the retainer ring (68) includes a body portion (70) and a holding lip (78) protruding radially inward from an inner periphery (80) of the body portion (70) and overlying an outer edge of the workpiece (32) to reduce the first diameter (53) of the workpiece contacting side (26) to the second diameter (84). In an alternative embodiment, the carrier base (24) is modified to reduce the first diameter (53) of the workpiece contacting side to the second diameter (84). Correspondingly, a width of the retainer ring 106 is defined to include a value substantially equivalent to one half of the difference between the first diameter (53) and the second diameter (84).
Description
- The present invention relates to the field of chemical mechanical polishing machines. More specifically, the present invention relates to a method and apparatus for polishing a semiconductor wafer to obtain a minimal edge exclusion.
- The production of integrated circuits begins with the creation of high quality semiconductor wafers. The semiconductor wafers are typically polished prior to integrated circuit fabrication so that a flat surface is available upon which the circuit fabrication can take place. Additionally, during the integrated circuit fabrication process, layers of, for example, conductors and dielectrics, are built up on the wafer, on top of which other such layers are to be created. Thus, it is typically necessary to “re-flatten” the wafer surface during the actual fabrication of the integrated circuit and not merely before it. The act of re-flattening is referred to as planarization.
- Chemical mechanical polishing (CMP) is a process for improving the surface planarity of a semiconductor wafer and involves the use of mechanical pad polishing systems usually with a silica-based slurry. CMP generally includes attaching one side of the wafer to a flat surface of a wafer carrier or chuck and pressing the wafer against a flat polishing surface. The polishing surface is moved under the wafer, and the wafer may also be rotated about its vertical axis and oscillated back and forth to improve polishing action. The polishing surface is generally a pad attached to a rigid flat table which is rotated to provide movement and onto which an abrasive and/or chemical slurry is pumped. The joint functions of the pad, the slurry, and the relative movements of the components produce a combined chemical and mechanical process at the wafer surface which produces a highly flat surface on a wafer where surface variations are kept to less than, for example, 0.5 μm.
- However, prior art CMP systems for planarizing semiconductor wafers have a limitation related to polishing uniformity known as “edge exclusion.” Edge exclusion occurs when too much of the exposed surface of the semiconductor wafer surface is polished. This causes the edge or outer portion of the wafer to be unusable for integrated circuit fabrication. Thus, the larger the edge exclusion on the semiconductor wafer, the lower the number of integrated circuits that a fabrication facility can produce per wafer. For example, prior art CMP systems typically produce an edge exclusion of approximately six millimeters wide on an eight inch (i.e., 203.2 mm) diameter wafer. This six millimeter edge exclusion represents an approximate eleven and a half percent reduction of surface area of a wafer that may be used for integrated circuit fabrication.
- Given semiconductor processing costs, it is quite possible that a single eight inch partially processed wafer is worth $10,000 or more in United States currency when planarization is performed. Accordingly, the high cost of complex semiconductor wafers combined with a highly competitive market has driven the need for a reduction in the size of the edge exclusion in order to maximize the number of integrated circuits that may be fabricated on a single wafer.
- In an attempt to respond to this need, original equipment manufacturers (OEMs) are manufacturing CMP systems that now yield an edge exclusion of approximately three millimeters. Thus, on an eight inch wafer, this represents nearly a six and a half percent increase in useable surface area over wafers polished using CMP systems producing a six millimeter edge extension. These newly designed CMP systems may cost in the range of two to three million dollars. For those fabrication facilities that have significant capital to invest, the purchase of a new CMP system may be acceptable. However, for those fabrication facilities in which financial resources may not be so readily available or for those that already own a CMP system, the investment of a new CMP system may be quite objectionable.
- Other OEMs and second source manufacturers have attempted to retrofit existing CMP systems in order to yield the desired three millimeter edge exclusion. Such retrofits involve software and hardware configuration changes that involve the replacement of, for example, the wafer carrier assembly of a CMP system, the inclusion of a variable pressurized retaining ring and corresponding software processes, redesigned polishing pads, and so forth. Such aftermarket parts are typically not part of an OEM's core business. Hence, this creates problems for the OEMs in terms of investment of time and effort in engineering and producing these aftermarket products. Moreover, the development cost of new components and software is typically passed to the consumer, i.e., the fabrication facilities that purchase the retrofit components for their existing CMP systems. While this investment may not be as great as purchasing a new CMP system, these modifications to existing equipment can still cost in the range of fifteen to seventy thousand dollars when installed. Again, such costs may be objectionable to some fabrication facilities.
- Accordingly, it is an advantage of the present invention that an improved retainer ring for a wafer carrier assembly and a method for polishing a workpiece utilizing an existing polishing machine are provided.
- It is another advantage of the present invention that it limits edge exclusion compared to that which occurs on a semiconductor wafer polished by known processes.
- Yet another advantage of the present invention is that it forms a simple modification to existing wafer carrier assemblies and through the modification improves the CMP process for semiconductor wafers.
- The above and other advantages of the present invention are carried out in one form by a retainer ring for retaining a workpiece within a workpiece carrier assembly of a polishing machine. The workpiece carrier assembly includes a carrier base for holding a first surface of the workpiece and for abutting a second surface, opposite the first surface, of the workpiece against a polishing pad of the polishing machine. The retainer ring comprises a body portion configured to be disposed concentrically on an outer periphery of the carrier base and a holding lip for retaining the workpiece, the holding lip protruding radially inward from an inner periphery of the body portion.
- The above and other advantages of the present invention are carried out in another form by a method for utilizing a polishing machine to polish a workpiece having a minimal edge exclusion region. The polishing machine includes a workpiece carrier assembly having a carrier base with a workpiece contacting side for holding a first surface of the workpiece. The workpiece contacting side of the carrier base exhibits a first diameter. The method calls for adapting the carrier base to reduce the first diameter of the workpiece contacting side to a second diameter and providing a retainer ring disposed concentrically on an outer periphery of the carrier base for retaining the workpiece when the workpiece is held by the carrier base. The method further calls for applying pressure on an upper side, opposite from the workpiece contacting side, of the carrier base to urge a second surface of the workpiece into sliding engagement with a polishing pad of the polishing machine.
- A more complete understanding of the present invention may be derived by referring to the detailed description and claims when considered in connection with the Figures, wherein like reference numbers refer to similar items throughout the Figures, and:
- FIG. 1 shows a partial block diagram of a chemical mechanical polishing (CMP) machine that may use the preferred embodiment of the present invention;
- FIG. 2 shows a bottom view of a semiconductor wafer surrounded by an existing retainer ring attached to a carrier base of the CMP machine of FIG. 1;
- FIG. 3 shows a perspective view of a retainer ring in accordance with a preferred embodiment of the present invention;
- FIG. 4 shows a cross-sectional side view of a workpiece carrier assembly of the CMP machine of FIG. 1 with the retainer ring of FIG. 3;
- FIG. 5 shows a semiconductor wafer polished in accordance with a preferred embodiment of the present invention; and
- FIG. 6 shows a cross-sectional side view of a workpiece carrier assembly of the CMP machine of FIG. 1 with a carrier base and a retainer ring in accordance with an alternative embodiment of the present invention.
- FIG. 1 shows a partial block diagram of a chemical mechanical polishing (CMP)
machine 20 that may use the preferred embodiment of the present invention.CMP machine 20 generally includes aworkpiece carrier assembly 22 having acarrier base 24 with aworkpiece contacting side 26 and anupper side 28, opposite fromworkpiece contacting side 26.Workpiece contacting side 26 is configured to hold afirst surface 30 of a workpiece, orsemiconductor wafer 32.Workpiece carrier assembly 22 picks upsemiconductor wafer 32 by a vacuum force and places asecond surface 34, oppositefirst surface 30, ofwafer 32 in contact with apolishing pad 36 supported by aplaten 38. Slurry 40 is applied topolishing pad 36. - Pressure, as represented by an
arrow 42, is applied onupper side 28 ofcarrier base 24 so that semiconductor wafer 32contacts polishing pad 36. Rotation ofcarrier assembly 22, as represented by a second arrow 43, urgessecond surface 34 ofsemiconductor wafer 32 in sliding engagement withpolishing pad 36 so thatsemiconductor wafer 32 is conditioned in the CMP process. -
CMP machine 20 represents a conventional chemical mechanical polishing system. Hence, those skilled in the art will recognize thatCMP machine 20 may include features such as a user interface, input and output elements for supplying and receiving semiconductor wafers, multiple workpiece carrier assemblies, necessary cabinets and access panels for the mechanical and electrical components withinmachine 20, and so forth (not shown) and will not be discussed in detail herein. Software programs resident in computer memory ofCMP machine 20 function to control the downward pressure onsemiconductor wafer 32, the rotational speed ofcarrier assembly 22, the application ofslurry 40 onpolishing pad 36, and so forth. - In addition,
CMP machine 20 is shown using rotary motion to rotatesemiconductor wafer 32 relative to polishingpad 36 for clarity of illustration. However, it should be understood to those skilled in the art thatCMP machine 20 may use a combination of rotational and orbital motion, or rotational and linear motion. That is,carrier assembly 22 may rotate in a circular path, while polishingpad 36 rotates in an orbital path. Alternatively,carrier assembly 22 may rotate in a circular path, while polishingpad 36 moves in a linear path. - FIG. 2 shows a bottom view of
semiconductor wafer 32 surrounded by an existingretainer ring 44 attached tocarrier base 24 ofCMP machine 20 of FIG. 1.Retainer ring 44 was not shown in FIG. 1 so thatsemiconductor wafer 32 would be viewable betweencarrier base 24 and polishingpad 36. However,CMP machine 20 typically includesretainer ring 44 which functions to retainwafer 32 within a pocket of workpiece carrier assembly 22 (FIG. 1) formed byworkpiece contacting side 26 and aninner periphery 48 ofretainer ring 44. - FIG. 2 further shows
semiconductor wafer 32 having anedge exclusion region 50 about aperimeter 52 ofwafer 32 that forms in the conventional CMP process.Wafer 32 floats within the pocket formed byworkpiece contacting side 26 andinner periphery 48 ofretainer ring 44.Workpiece contacting side 26 exhibits afirst diameter 53, defined byinner periphery 48, that is greater than adiameter 55 ofwafer 32. Accordingly, when pressure 42 (FIG. 1) is applied on upper side 28 (FIG. 1) of carrier base 24 (FIG. 1) so thatwafer 32 contacts polishing pad 36 (FIG. 1), polishingpad 36 may be forced into agap 54 betweeninner periphery 48 ofretainer ring 44 andperimeter 52 ofwafer 32. Consequently, excessive polishing ofsemiconductor wafer 32 occurs aboutperimeter 52 to formedge exclusion region 50. -
Edge exclusion region 50 is defined by a width 57. Width 57 ofedge exclusion region 50 significantly affects the ability to include integrated circuits onsemiconductor wafer 32. For example, anintegrated circuit pattern 56 is formed onsecond surface 34 ofsemiconductor wafer 32. As can be seen, inintegrated circuit pattern 56,integrated circuits edge exclusion region 50. Thus,edge exclusion region 50 forms an area onsecond surface 34 ofwafer 32 which excludes the acceptable fabrication of integrated circuits. Width 57 ofedge exclusion region 50 typically ranges from 5 to 7 mm. - The present invention limits width57 of
edge exclusion region 50 when polishingwafer 32 utilizingCMP machine 20 compared to that which occurs on a semiconductor wafer polished by known processes. In particular, width 57 ofedge exclusion region 50 is decreased from 5 to 7 mm on an eight inch (i.e. 203.2 mm) diameter wafer to approximately 3 mm. Width 57 ofedge exclusion region 50 is decreased by adaptingcarrier base 24 to reducefirst diameter 53 ofworkpiece contacting side 24, thus decreasinggap 54 and allowing less space in whichwafer 32 may float and in whichpolishing pad 36 may be forced. - Referring to FIGS. 3 and 4, FIG. 3 shows a perspective view of a
retainer ring 68 in accordance with a preferred embodiment of the present invention. FIG. 4 shows a cross-sectional side view ofworkpiece carrier assembly 22 of CMP machine 20 (FIG. 1) withretainer ring 68.Retainer ring 68 is provided to replace existing retainer ring 44 (FIG. 2) ofworkpiece carrier assembly 22 and functions to retainwafer 32 withinworkpiece carrier assembly 22 of CMP machine 20 (FIG. 1). -
Retainer ring 68 includes abody portion 70 configured to be disposed concentrically on anouter periphery 72 ofcarrier base 24 ofworkpiece carrier assembly 22.Body portion 70 includes threadedholes 74, andbolts 76couple retainer ring 68 tocarrier base 24. -
Retainer ring 68 further includes a holdinglip 78 protruding radially inward from aninner periphery 80 ofbody portion 70. Awidth 79 of holdinglip 78 is shown greatly exaggerated in FIG. 4 for clarity of illustration. However,retainer ring 68 is manufactured such thatwidth 79 of holdinglip 78 is in a range of 0.005 to 0.012 inches (0.127 to 0.3048 mm). For example, for a CMP machine, such asCMP machine 20, configured to polishsemiconductor wafer 32 having diameter 55 (FIG. 2) of eight inches (203.2 mm), holdinglip 78 may protrude radially inward substantially 0.010 inches (0.254 mm) frominner periphery 80. - When
retainer ring 68 is coupled tocarrier base 24,retainer ring 68 is positioned such that holdinglip 78 overlies anouter edge 82 ofworkpiece contacting side 26 ofcarrier base 24 to reducefirst diameter 53 ofworkpiece contacting side 26 to asecond diameter 84. By way of example whenwidth 79 of holdinglip 78 is substantially 0.010 inches,second diameter 84 is reduced substantially 0.020 inches fromfirst diameter 53. Thus, whenwafer 32 is held inworkpiece carrier assembly 22, holdinglip 78 approachesperimeter 52 ofwafer 32 and a gap 86 formed betweenwafer 32 andinner periphery 80 ofbody portion 70 is minimized. - Holding
lip 78 exhibits aheight 88 configured to accommodate the thickness ofwafer 32. Thus, likeretainer ring 44,retainer ring 68 functions to retainwafer 32 within apocket 90 ofworkpiece carrier assembly 22 formed byworkpiece contacting side 26 and holdinglip 78 ofretainer ring 68 whenwafer 32 is held bycarrier base 24. - In a preferred embodiment,
retainer ring 68 is readily machined from polyphenyl sulfide (PPS). PPS may be unmodified or modified with modifiers such as Teflon® PTFE (Polytetrafluoroethylene), MoS (Molybdenum disulfide), graphite, and so forth. PPS is rigid, hard, and resistant to corrosion. Alternatively,retainer ring 68 may be fabricated from Delrin® also characterized by strength, stiffness, hardness, and solvent and fuel resistance.Retainer ring 68 is precision machined to achieve tolerances of +/− one micron for holdinglip 78. - FIG. 5 shows
semiconductor wafer 32 polished in accordance with a preferred embodiment of the present invention and having anedge exclusion region 92. It has been discovered that the replacement of existing retainer ring 44 (FIG. 2) withretainer ring 68 inworkpiece carrier assembly 22 results inedge exclusion region 92 having awidth 93 of approximately 3 mm being formed onwafer 32 during the chemical mechanical polishing process utilizingCMP machine 20.Edge exclusion region 92 withwidth 93 of 3 mm represents a minimal edge exclusion currently achievable on newly designed CMP machines and CMP machines with redesigned workpiece carrier assemblies. -
Width 93 ofedge exclusion region 92 represents nearly a fifty percent reduction ofedge exclusion region 92 over edge exclusion region 50 (FIG. 2) formed during a conventional CMP process using retainer ring 44 (FIG. 2). This reduction of the edge exclusion nets an approximate 6.4% increase in usable surface area ofsemiconductor wafer 32 overedge exclusion region 50. As such, anintegrated circuit pattern 94, having the same surface area asintegrated circuit pattern 56 of FIG. 2, includesintegrated circuits edge exclusion region 92 onsemiconductor wafer 32, the yield of integrated circuits fromwafer 32 increases. - Moreover, the replacement of
retainer ring 44 withretainer ring 68 onworkpiece carrier assembly 22 is far less costly than replacement of the entire workpiece carrier assembly on an existing CMP machine, or purchase of an entirely new CMP machine. For example, through its simple manufacture and retrofit onto the existing carrier base 24 (FIG. 3),retainer ring 68 results in significant savings for the consumer in terms of time and effort in testing and qualifying replacement carrier assemblies or purchasing a replacement CMP machine. Thus,retainer ring 68 may be one to three hundredths of the cost of a replacement carrier assembly or one thousandth of the cost of a replacement CMP machine. - FIG. 6 shows a cross-sectional side view of
workpiece carrier assembly 22 of the CMP machine of FIG. 1 with acarrier base 104 and a retainer ring 106 in accordance with an alternative embodiment of the present invention.Carrier base 104 may be a replacement unit for carrier base 24 (FIG. 4). As such,carrier base 104 and retainer ring 106 may form a retrofit kit that may be used to upgrade an existing CMP machine to polish wafers to achieveedge exclusion region 92 with width 93 (FIG. 5) of 3 mm rather than edge exclusion region 50 (FIG. 2) with width 57 (FIG. 2) of 6 mm. Alternatively,carrier base 104 may be adapted fromcarrier base 24 by precision machining the existingcarrier base 24. In either case,carrier base 104 has aworkpiece contacting side 108 exhibitingsecond diameter 84 that is reduced from first diameter 53 (FIG. 2) by a value in a range of 0.010 to 0.024 inches (0.254 to 0.6096 mm). - Retainer ring106 is provided to replace retainer ring 44 (FIG. 2). That is, retainer ring 106 is disposed concentrically on an
outer periphery 112 ofcarrier base 104 and serves to retainsemiconductor wafer 32 whenwafer 32 is held bycarrier base 104. Awidth 114 of retainer ring 106 is defined to include a value substantially equivalent to a one half of a difference betweenfirst diameter 53 andsecond diameter 84. By way of example, whensecond diameter 84 is reduced fromdiameter 53 by a total of 0.020 inches,width 114 is a sum of a width (not shown) ofretainer ring 44 and 0.010 inches. - The reduction of
second diameter 84 fromfirst diameter 53, and the corresponding increase ofwidth 114 of retainer ring 106 relative toretainer ring 44, achieves a decrease in a gap 116 between retainer ring 106 andperimeter 52 ofwafer 32 relative to gap 54 (FIG. 2). As such, edge exclusion region 92 (FIG. 5) withwidth 93 of 3 mm is produced. - The replacement of
carrier base 24 withcarrier base 104, or alternatively, adaptation ofcarrier base 24 to producecarrier base 104, and the replacement ofretainer ring 44 with retainer ring 106, achieves significant cost savings over the replacement ofworkpiece carrier assembly 22 or the replacement ofCMP machine 20. - In summary, the present invention teaches of an improved retainer ring for a wafer carrier assembly and a method for polishing a workpiece using an existing chemical mechanical polishing machine. By decreasing the amount of gap between the perimeter of a semiconductor wafer and a retainer ring, when the wafer is positioned in a carrier base of a workpiece carrier, the edge exclusion region is reduced by nearly fifty percent over that which occurs on a semiconductor wafer polished by previously known chemical mechanical polishing processes. In addition, the retainer ring and the adaptation of the carrier base to reduce the diameter of the workpiece contacting side of the carrier base form a simple and cost effective modification to existing wafer carrier assemblies and through the modification improves the CMP process for semiconductor wafers.
- Although the preferred embodiments of the invention have been illustrated and described in detail, it will be readily apparent to those skilled in the art that various modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims. For example, the teachings of the present invention may be adapted to successfully achieve minimal edge exclusion regions on workpieces of different diameters and manufactured from a variety of materials. In addition, the teachings of the present invention art not limited to existing CMP machines but may be adapted for use with new CMP machines to achieve minimal edge exclusion regions on workpieces.
Claims (16)
1. A retainer ring for retaining a workpiece within a workpiece carrier assembly of a polishing machine, said workpiece carrier assembly including a carrier base for holding a first surface of said workpiece and for abutting a second surface, opposite said first surface, of said workpiece against a polishing pad of said polishing machine, said retainer ring comprising:
a body portion configured to be disposed concentrically on an outer periphery of said carrier base; and
a holding lip for retaining said workpiece, said holding lip protruding radially inward from an inner periphery of said body portion.
2. A retainer ring as claimed in claim 1 wherein said body portion is configured to be coupled to said carrier base.
3. A retainer ring as claimed in claim 1 wherein when said workpiece is held in said carrier base, said holding lip is configured to approach a perimeter of said workpiece to minimize a gap between said holding lip and said perimeter.
4. A retainer ring as claimed in claim 1 wherein said holding lip exhibits a width, said width protruding radially inward, and said width being in a range of 0.005 and 0.012 inches.
5. A retainer ring as claimed in claim 4 wherein said width of said holding lip is substantially 0.010 inches.
6. A retainer ring as claimed in claim 1 wherein said carrier base includes a workpiece contacting side having a first diameter, and said holding lip is configured to overlie an outer edge of said workpiece contacting side of said carrier base to reduce said first diameter of said workpiece contacting side to a second diameter.
7. A retainer ring as claimed in claim 1 wherein said holding lip exhibits a height configured to accommodate a thickness of said workpiece.
8. A retainer ring as claimed in claim 1 wherein said retainer ring is adapted to replace an existing retainer ring of said workpiece carrier assembly.
9. A method for utilizing a polishing machine to polish a workpiece to achieve a minimal edge exclusion region, said polishing machine including a workpiece carrier assembly having a carrier base with a workpiece contacting side for holding a first surface of said workpiece, said workpiece contacting side exhibiting a first diameter, and said method comprising:
adapting said carrier base to reduce said first diameter of said workpiece contacting side to a second diameter;
providing a retainer ring disposed concentrically on an outer periphery of said carrier base for retaining said workpiece when said workpiece is held by said carrier base; and
applying pressure on an upper side, opposite from said workpiece contacting side, of said carrier base to urge a second surface of said workpiece into sliding engagement with a polishing pad of said polishing machine.
10. A method as claimed in claim 9 wherein said carrier base is an existing carrier base exhibiting said first diameter, and said adapting operation includes modifying said existing carrier base to reduce said first diameter of said workpiece contacting side to obtain said second diameter.
11. A method as claimed in claim 10 wherein said providing operation comprises defining a width of said retainer ring to include a value substantially equivalent to one half of a difference between said first diameter and said second diameter.
12. A method as claimed in claim 11 wherein said value is in a range of 0.005 to 0.012 inches.
13. A method as claimed in claim 9 wherein said carrier base is an existing carrier base exhibiting said first diameter, and said providing operation includes:
producing said retainer ring having a body portion and a holding lip protruding radially inward from an inner periphery of said body portion, said body portion being configured to be disposed concentrically on said outer periphery of said carrier base; and
positioning said retaining ring such that said holding lip overlies an outer edge of said workpiece contacting side of said carrier base to reduce said first diameter of said workpiece contacting side to obtain said second diameter.
14. A method as claimed in claim 13 wherein said producing operation includes establishing a width of said holding lip to be substantially equivalent to one half of a difference between said first diameter and said second diameter.
15. A method as claimed in claim 14 wherein said width of said holding lip is in a range of 0.005 to 0.012 inches.
16. A workpiece carrier assembly retrofit kit for adapting a workpiece carrier assembly of a polishing machine to polish a workpiece having a minimal edge exclusion region, said workpiece carrier assembly including an existing carrier base and an existing retainer ring coupled to said existing carrier base, said existing carrier base having a workpiece contacting side exhibiting a first diameter, said existing retainer ring exhibiting a first width, and said kit comprising:
a carrier base configured to replace said existing carrier base, said carrier base having a workpiece contacting side exhibiting a second diameter, said second diameter being less than said first diameter of said existing carrier base; and
a retaining ring configured to couple to said carrier base, said retaining ring exhibiting a second width, said second width being substantially equivalent to a sum of said first width and a value substantially equivalent to one half of a difference between said first diameter and said second diameter.
Priority Applications (1)
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US09/850,578 US20020164926A1 (en) | 2001-05-07 | 2001-05-07 | Retainer ring and method for polishing a workpiece |
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US09/850,578 US20020164926A1 (en) | 2001-05-07 | 2001-05-07 | Retainer ring and method for polishing a workpiece |
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US20020164926A1 true US20020164926A1 (en) | 2002-11-07 |
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US09/850,578 Abandoned US20020164926A1 (en) | 2001-05-07 | 2001-05-07 | Retainer ring and method for polishing a workpiece |
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Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20040077167A1 (en) * | 2002-10-11 | 2004-04-22 | Willis George D. | Retaining ring for use on a carrier of a polishing apparatus |
US20080039000A1 (en) * | 2000-09-08 | 2008-02-14 | Applied Materials, Inc. | Reataining ring and articles for carrier head |
US20140120803A1 (en) * | 2012-10-26 | 2014-05-01 | Hung Chih Chen | Retaining ring with selected stiffness and thickness |
CN106463384A (en) * | 2014-07-18 | 2017-02-22 | 应用材料公司 | Modifying substrate thickness profiles |
-
2001
- 2001-05-07 US US09/850,578 patent/US20020164926A1/en not_active Abandoned
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20080039000A1 (en) * | 2000-09-08 | 2008-02-14 | Applied Materials, Inc. | Reataining ring and articles for carrier head |
US20100144255A1 (en) * | 2000-09-08 | 2010-06-10 | Applied Materials, Inc., A Delaware Corporation | Retaining ring and articles for carrier head |
US8376813B2 (en) | 2000-09-08 | 2013-02-19 | Applied Materials, Inc. | Retaining ring and articles for carrier head |
US8535121B2 (en) | 2000-09-08 | 2013-09-17 | Applied Materials, Inc. | Retaining ring and articles for carrier head |
US20040077167A1 (en) * | 2002-10-11 | 2004-04-22 | Willis George D. | Retaining ring for use on a carrier of a polishing apparatus |
US7160493B2 (en) * | 2002-10-11 | 2007-01-09 | Semplastics, Llc | Retaining ring for use on a carrier of a polishing apparatus |
US20140120803A1 (en) * | 2012-10-26 | 2014-05-01 | Hung Chih Chen | Retaining ring with selected stiffness and thickness |
US8998676B2 (en) * | 2012-10-26 | 2015-04-07 | Applied Materials, Inc. | Retaining ring with selected stiffness and thickness |
US9492905B2 (en) | 2012-10-26 | 2016-11-15 | Applied Materials, Inc. | Retaining ring with selected stiffness and thickness |
CN106463384A (en) * | 2014-07-18 | 2017-02-22 | 应用材料公司 | Modifying substrate thickness profiles |
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Owner name: TOTAL FAB SOLUTIONS, INC., ARIZONA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:SIMON, MARK G.;REEL/FRAME:012074/0544 Effective date: 20010503 |
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