US20060217049A1 - Perforation and grooving for polishing articles - Google Patents

Abstract

Methods, articles of manufacture, and apparatus are provided for depositing and planarizing one or more layers of material on a substrate, or combinations thereof, are disclosed. In one embodiment, an article of manufacture is provided for polishing a substrate, comprising a polishing article having a polishing surface, a plurality of perforations formed in at least a portion of the polishing article for flow of material therethrough, and a plurality of grooves disposed in the polishing surface. The article of manufacture may be used in a method for processing a substrate, comprising positioning the substrate in an electrolyte solution containing a polishing article, optionally depositing a material on the substrate by an electrochemical deposition method, and polishing the substrate with the polishing article.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS
• This application is a divisional of U.S. patent application Ser. No. 10/026,854, filed Dec. 20, 2001, which claims benefit of U.S. provisional Patent Application Ser. No. 60/258,162, filed Dec. 22, 2000, both applications incorporated by reference herein.
BACKGROUND OF THE INVENTION
• 1. Field of the Invention
• Embodiments of the invention relate to apparatus and methods for deposition and/or planarization of a material, such as a metal, on a substrate.
• 2. Background of the Related Art
• Sub-quarter micron multi-level metallization is one of the key technologies for the next generation of ultra large scale integration (ULSI). The multilevel interconnects that lie at the heart of this technology require planarization of interconnect features formed in high aspect ratio apertures, including contacts, vias, lines and other features. Reliable formation of these interconnect features is very important to the success of ULSI and to the continued effort to increase circuit density and quality on individual substrates and die.
• In the fabrication of integrated circuits and other electronic devices, multiple layers of conducting, semiconducting, and dielectric materials are deposited on or removed from a surface of a substrate. Thin layers of conducting, semiconducting, and dielectric materials may be deposited by a number of deposition techniques. Common deposition techniques in modern processing include physical vapor deposition (PVD), also known as sputtering, chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PECVD), and now electrochemical plating (ECP).
• Often it is necessary to polish a surface of a substrate to remove high topography, surface defects, metal residues, scratches or embedded particles formed from the deposition and removal of materials from a substrate surface. One common polishing process is known as chemical mechanical polishing (CMP) and is used to improve the quality and reliability of the electronic devices formed on the substrate. CMP is broadly defined herein as polishing a substrate by chemical activity, mechanical activity, or a combination of both chemical and mechanical activity.
• Currently, the semiconductor industry is developing processes and apparatus for depositing conductive materials on a substrate and in situ polishing of the substrate to improve manufacturing throughput. One such process is electrochemical mechanical plating process (ECMPP) which provides for the deposition of a conductive material, such as copper, on a substrate surface in an electrolyte while concurrently polishing the substrate to minimize the amount of conductive material deposited over features on the substrate. Features formed on the substrate include a dense array of narrow features and wide features. Material is deposited over both features at the same rate with the narrow features being filled first and excess material forming over the narrow features as wide features are filled. This excess material over the dense array of narrow features is referred to as the overburden and results in a non-planar surface after deposition. The overburden is typically removed using CMP processes or in some cases etchback processes.
• An important goal of polishing, especially in ECMPP, is achieving uniform planarity of the substrate surface with minimal overburden. It is highly desirable that the polishing process uniformly removes material from the surface of substrates as well as removing non-uniform layers, which have been deposited on the substrate. Successful ECMPP also requires process repeatability from one substraThe polishing pressure preferably has e next. Thus, uniformity must be achieved not only for a single substrate, but also for a series of substrates processed in a batch.
• One difficulty with ECMPP processes is that the conductive material to be deposited may not be evenly distributed in the electrolyte over the surface of the substrate. Uneven distribution over the substrate may result in non-uniformity and the formation of defects, such as voids, in features formed in the surface of the substrate, which can detrimentally affect the quality of the substrate produced using the ECMPP process. One solution to this problem is to use a porous pad during ECMPP to allow electrolyte to reach the substrate surface. However, under current processing conditions, the ECMPP process requires a greater quantity of electrolyte at the substrate surface than what is currently provided by conventional porous polishing pads.
• Additionally, for ECMPP processes, the porous pad is required to be held in position during processing to provide for uniform polishing. However, it has been found to be technically challenging to hold a porous pad in position for polishing while allowing electrolyte to flow freely through the pad to the substrate surface.
• As a result, there is a need for an article of manufacture, process, and apparatus to improve polishing uniformity during deposition and polishing of a conductive material on a substrate surface.
SUMMARY OF THE INVENTION
• Embodiments of the invention generally provides an article of manufacture, a method and an apparatus for depositing a layer, planarizing a layer, or combinations thereof, on a substrate using electrochemical deposition techniques, polishing techniques, or combinations thereof.
• In one embodiment, an article of manufacture for depositing and planarizing a material on a substrate is described. The article of manufacture includes a polishing article having center portion and a perimeter portion defining a polishing surface, a plurality of passages formed through the polishing article for flow of material therethrough, and a plurality of grooves disposed in the polishing surface.
• In another embodiment, an article of manufacture for depositing and planarizing a material on a substrate is described. The article of manufacture includes a polishing article having a polishing surface and a plurality of holes disposed at least partially through the polishing article, and a plurality of grooves disposed in the polishing surface, wherein an upper end of each of the plurality of holes is recessed below the polishing surface.
• In another embodiment, a system for processing a substrate is described. The system includes a platform having a rotating support, a conductive layer coupled to the rotating support, a polishing article coupled to the conductive layer with a sub-pad therebetween. In this embodiment, the polishing article includes a conductive polishing surface having a plurality of grooves formed therein, each of the plurality of grooves having a bottom, wherein a plurality of holes extend through the polishing article and intersect with the bottom of a portion of the plurality of grooves.
BRIEF DESCRIPTION OF THE DRAWINGS
• So that the manner in which the above recited features are attained and can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof 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.
• FIG. 1 is a cross sectional view of one embodiment of a processing apparatus showing a substrate disposed above a polishing article;
• FIG. 2 is a partial cross sectional view of one embodiment of a carrier head assembly;
• FIGS. 3A-3D are schematic views of embodiments of a polishing article having grooves and passages formed therein;
• FIG. 4 is a schematic view of another embodiment of a polishing article having grooves and passages formed therein;
• FIG. 5 is a schematic view of another embodiment of a polishing article having grooves and passages formed therein;
• FIG. 6 is a cross sectional view of one embodiment of a processing apparatus showing a substrate contacting a polishing article;
• FIG. 7 is a plan view of one embodiment of a processing platform incorporating embodiments of the processing apparatus of the invention; and
• FIG. 8 is a sectional view of a plating station of the platform ofFIG. 7.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
• The words and phrases used herein should be given their ordinary and customary meaning in the art by one skilled in the art unless otherwise further defined. Chemical-mechanical polishing should be broadly construed and includes, but is not limited to, abrading a substrate surface by chemical activity, mechanical activity, or a combination of both chemical and mechanical activity. Electropolishing should be broadly construed and includes, but is not limited to, planarizing a substrate by the application of electrochemical activity, such as by anodic dissolution.
• Electrochemical mechanical polishing (ECMP) should be broadly construed and includes, but is not limited to, planarizing a substrate by the application of electrochemical activity, mechanical activity, or a combination of both electrochemical and mechanical activity to remove material from a substrate surface. Electrochemical mechanical plating process (ECMPP) should be broadly construed and includes, but is not limited to, electrochemically depositing material on a substrate and concurrently planarizing the deposited material by the application of electrochemical activity, mechanical activity, or a combination of both electrochemical and mechanical activity.
• FIG. 1 is a cross sectional view of one embodiment of anapparatus20 for depositing a layer, planarizing a layer, or combinations thereof, a metal layer on asubstrate22. One example of an apparatus that may be adapted to benefit from aspects of the invention is an ELECTRA® electroplating tool, available from Applied Materials, Inc., of Santa Clara, Calif. An example of a suitable electroplating tool is described in U.S. Pat. No. 6,258,220, filed on Apr. 8, 2000, and issued Jul. 10, 2001, assigned to common assignee Applied Materials, Inc., the description of which is incorporated herein by reference to the extent not inconsistent with the invention. Theapparatus20 generally includes acarrier head assembly30 movably supported by astanchion80 over apartial enclosure34. Thestanchion80 andenclosure34 are generally disposed on acommon base82. Thestanchion80 generally includes abase support84 and alift mechanism86. Thebase support84 extends perpendicularly from thebase82 and may be rotatable on its axis so that thecarrier assembly30 may be moved over thepartial enclosure34 or to other positions, for example, to other enclosures or to interface with other processing systems not shown.
• Thelift mechanism86 is coupled to thecarrier assembly30. Thelift mechanism86 generally controls the elevation of thecarrier assembly30 in relation to thepartial enclosure34. Thelift mechanism86 includes alinear actuator88, such as a ball screw, lead screw, pneumatic cylinder and the like, and aguide90 that slides along arail92. Therail92 is coupled to thebase support84 by ahinge94 so that therail92 of the lift mechanism86 (i.e., direction of motion) may be controllably orientated through a range of angles between about 90 to about 60 degrees relative to horizontal. Thelift mechanism86 and hinge94 allows thecarrier assembly30 holding asubstrate22 to be lowered into thepartial enclosure34 in various orientations. For example, to minimize the formation of bubbles upon thesubstrate22 when interfacing with fluids disposed within theenclosure34, thesubstrate22 may be orientated at an angle during entry into thepartial enclosure34 and then rotated to a horizontal orientation once therein.
• Thepartial enclosure34 generally defines a container or electrolyte cell in which an electrolyte or other polishing/deposition fluid can be confined. The electrolyte used in processing thesubstrate22 can include metals such as copper, aluminum, tungsten, gold, silver or other materials which can be electrochemically deposited onto a substrate. As one example, copper sulfate (CuSO₄) can be used as the electrolyte. Copper containing solutions used for plating are available from Shipley Ronel, a division of Rohm and Haas, headquartered in Philadelphia, Pa., under the tradename Ultrafill 2000.
• Theenclosure34 typically includes ananode26, adiffuser plate44 and a polishingarticle28 disposed therein. A polishingarticle28, such as a polishing pad, is disposed and supported in the electrolyte cell on thediffuser plate44. Thepartial enclosure34 can be a bowl shaped member made of a plastic such as fluoropolymers, TEFLON®, PFA, PE, PES, or other materials that are compatible with plating chemistries. Thepartial enclosure34 is connected to ashaft32 on its lower surface that extends below thebase82. Alternatively, thepartial enclosure34 can be connected to a mounting platform that is connected to theshaft32. Theshaft32 is connected to an actuator (not shown), such as a motor, e.g., a stepper motor, disposed in thebase82. The actuator is adapted to rotate thepartial enclosure34 about vertical axis x. In one embodiment, theshaft32 defines a central passage through which fluid is delivered into thepartial enclosure34 through a plurality ofports36 formed in theshaft32.
• Theanode26 is positioned at the lower portion of theenclosure34 where it may be immersed in the electrolyte solution.Anode26 can be a plate-like member, a plate having multiple holes formed therethrough or a plurality of anode pieces disposed in a permeable membrane or container. Theanode26 is preferably comprised of the material to be deposited, such as copper, nickel, aluminum, gold, silver, tungsten and other materials which can be electrochemically deposited on a substrate. In at least one embodiment, theanode26 comprises a consumable anode that may require periodic replacement. Alternatively, the anode may comprise non-consumable anode of a material other than the deposited material, such as platinum for a copper deposition.
• In at least one embodiment, theanode26 is a ring-shaped member defining a central opening through which the fluid inlet of theshaft32 is disposed. In embodiments where theanode26 is plate-like, a plurality of holes may be formed through the anode to allow passage of electrolyte therethrough. Theanode26 can alternatively be a ring anode, a plate anode, or a chamber confining plating material, including a permeable chamber or other enclosure.
• The polishingarticle28 can be a polishing pad or other type of volume spacer that is compatible with the fluid environment and the processing specifications. The polishingarticle28 is positioned at an upper end of thepartial enclosure34 and supported on its lower surface by thediffuser plate44. The metal ions can be supplied from afluid delivery line40 having anoutlet42 positioned above the polishingarticle28. The polishingarticle28 may be disposed adjacent to or in contact with theanode26.
• FIG. 3A is a top plan view of one embodiment of a polishing article according to aspects of the invention. Around pad240 of the polishingarticle28 is shown having a plurality ofpassages246 of a sufficient size and organization to allow the flow of electrolyte to the substrate surface. Thepassages246 are generally formed through the entire polishing article, such asround pad240. The invention does contemplate passages that are only partially formed in the surface polishing article without fluid flow therethrough. The partial passages (not shown) may function as localized reservoirs of polishing material in the polishing article during polishing.
• Thepassages246 may be spaced between about 0.1 inches and about 1.0 inches from one another. The passages may be circular passages having a diameter of between about ten-thousandths of an inch and about ½ of an inch. Further the number and shape of the passages may vary depending upon the apparatus, processing parameters, and ECMPP composition being used.
• The passages may form a pattern as desired by the operator and may include, for example, X-Y grids, offset X-Y grids, circular rings, a triangular pattern, a random pattern, or a spiral pattern, among others.FIGS. 3A, 4, and5 respectively, illustratepassages246,346, and446 in a spiral pattern, an offset X-Y grid pattern, and a random pattern.
• The polishing article may also comprisegrooves242 formed in the polishing surface248 therein to assist transport of fresh electrolyte from the bulk solution intoenclosure34 to the gap between thesubstrate22 and the polishing article. Thegrooves242 may be spaced between about 30 mils and about 300 mils apart from one another. Generally, grooves formed in the polishing article have a width between about 5 mils and about 30 mils, but may vary in size as required for polishing. An example of a groove pattern includes grooves of about 10 mils wide spaced about 60 mils apart from one another. Thegrooves242 may have various patterns, including a groove pattern of substantially circular concentric grooves on the polishing surface248 as shown inFIG. 3A, an X-Y pattern as shown inFIG. 4 and a triangular pattern as shown inFIG. 5. While these patterns are shown and described herein, other patterns can also be used. The pattern of thegrooves242 and the pattern of thepassages246 are generally independent patterns.
• FIG. 3B is a side schematic view of one embodiment of the polishing article along the line B. The pattern of thepassages246 is adapted to havepassages246 partially formed in thegrooves242 to provide electrolyte directly to thegrooves242. Interconnection of thepassages246 and thegrooves242 is believed to improve flow of the electrolyte from theenclosure34 to the substrate surface.
• FIG. 3C is a side schematic view of another embodiment of the polishing article. The pattern of thepassages246 is adapted to provide electrolyte flow to the surface of the polishing pad bypassages246 and routing or partially routing the electrolyte away from thegrooves242 to the surface bypassages246′. In a further embodiment,passages246 may be adapted to provide electrolyte directly to the surface of the polishing pad and bypassing all of the groves, as shown inFIG. 3D.
• The polishing article of theround pad240 may further have an extension orouter diameter244 larger than the area required to polish a substrate. Theouter diameter244 may be free of passages. Conductive material may be disposed on theouter diameter244 and/or inner diameter to provide or improve electrical conductance of the polishing article to the substrate surface during the ECMPP process. Further, theouter diameter244 may be fixed, by adhesives, vacuum, or mechanical forces, to another pad or object in a processing system to provide increased stability and more uniform polishing performance during the ECMPP process.
• FIG. 4 is a top plan view of another embodiment of apad having grooves342 disposed in an X-Y pattern on the polishingarticle348 of apolishing pad340.Passages346 may be disposed at the intersections of the y-axis and x-axis horizontally disposed grooves, and may also be disposed on a y-axis groove, a x-axis groove, or disposed in the polishingarticle348 outside of thegrooves342. Thepassages346 andgrooves342 are disposed in theinner diameter350 of the polishing article and the outer diameter of the polishing pad344 is typically free of passages. Theouter diameter350 of thepolishing pad340 may be free of grooves and passages.
• FIG. 5 is another embodiment of patterned polishingarticle448. In this embodiment,grooves442 may be disposed in an X-Y pattern with diagonally disposedgrooves454 intersecting the X-Y patternedgrooves442. Thediagonal grooves454 may be disposed at an angle between about 300 and about 600 from any of theX-Y grooves442.Passages446 may be disposed at the intersections of theX-Y grooves442, the intersections of theX-Y grooves442 anddiagonal grooves454, along any of thegrooves442 and454, or disposed in the polishingarticle448 outside of thegrooves442 and454. As described above, another embodiment of the polishingarticle448 may have a pattern of passages independent of any groove pattern, with intersection of passages and groves independent of one another. As shown inFIG. 5, thepassages446 andgrooves442 are disposed in the inner diameter of the polishing article and the outer diameter of thepolishing pad444 is typically free of passages. Theouter diameter450 of thepolishing pad440 may be free of grooves and passages.
• It is believed that thegrooves242 provide a supply of electrolyte to the substrate surface that is evenly distributed on the substrate surface allowing for a more even deposition and polishing, and thereby increasing substrate uniformity. It is further believed that the use of intersecting grooves and passages will allow electrolyte to enter through one set of passages, be evenly distributed around the substrate surface, and then removed through a second set of passages.
• The polishing article typically comprises a dielectric material (insulator or non-conductive material). Examples of dielectric material that may be used as polishing article include polyurethane pads commercially available from Rodel, Inc., of Phoenix, Ariz., or a PVDF pad from Asahi of Japan, or a fixed abrasive pad from 3M, of Minneapolis, Minn.
• The polishing article may include conductive material for electroplating deposition process and electropolishing processes or a dielectric for both electroplating, electropolishing, and electroless deposition processes. For an electroplating deposition and electropolishing process, the polishing article may comprise a conductive polymer, or a dielectric material such as a polymer including polyurethane, with conductive elements or materials (not shown) embedded or formed therein, to provide a conductive path over the polishing article. The conductive elements are electrically connected to one another in the polishing article and may contact the substrate surface when the substrate is in contact with the polishing article. For an electroless deposition, the polishing article can form an insulator material, or a material of low conductance, such as polyurethane.
• The polishing article may also include a porous polishing article, such as a porous polyurethane material to increase electrolyte flowthrough. The polishing article may comprise a plurality of pores of a sufficient size and organization to allow the flow of electrolyte to the substrate surface while preventing the flow of deposition by-products, such as accelerator and suppressor degradation by-products.
• The polishing article may be disposed on a porous or sub-pad having passages formed therein (not shown) during the ECMPP process. The polishing article may be affixed, for example adhesively affixed, to a sub-pad with the sub-pad's passages aligned with the passages of the polishing article to allow flow of electrolyte from theenclosure34 to the substrate surface. The use of a sub-pad, typically made of hard polishing materials such as the material used in an IC-1000™ pad, is believed to provide mechanical support for the polishing article when contacting thesubstrate22. The sub-pad may comprise an insulative material to limit any inadvertent deposition of material on the sub-pad.
• Alternatively, adiffuser plate44 is provided to support the polishing article in thepartial enclosure34 as shown inFIG. 1. Thediffuser plate44 can be secured in thepartial enclosure34 using fasteners such asscrews38 or other means such as snap or interference fit with the enclosure, being suspended therein and the like. Thediffuser plate44 can be made of a material such as a plastic, e.g., fluoropolymer, PE, TEFLON®, PFA, PES, HDPE, UHMW or the like. Thediffuser plate44, in at least one embodiment, includes a plurality of holes orchannels46 formed therein. Theholes46 are sized to enable fluid flow therethrough and to provide uniform distribution of electrolyte through the polishing article to thesubstrate22. The polishingarticle28 can be fastened to thediffuser plate44 using adhesives that are compatible with the fluid environment and the processing requirements.
• Thediffuser plate44 is preferably spaced from theanode26 to provide a wider process window, thus reducing the sensitivity of plating film thickness to the anode dimensions, and to separate the accelerator and suppressor decomposition by-products, for example, a mono-sulfide compound degraded from an accelerator, such as a bis(3-sulfopropyl) disulfide, C₆H₁₂Na₂O₆S₄, commercially available from the Raschig Corp. of Germany, from amain plating volume38 defined between the polishingarticle28 and thesubstrate22.
• While not shown, a membrane may be disposed between theanode26 and the polishingarticle28 to contain particles produced from the anode film from entering theenclosure34 and depositing as particles on the substrate surface. For example, the membrane is permeable to electrolyte flow, but is not typically permeable to accelerator and suppressor degradation by-products on the anode surface.
• The substrate carrier orhead assembly30 is movably positioned above the polishingarticle28. Thesubstrate carrier assembly30 is vertically movable above the polishingarticle28 and is laterally movable relative thereto. For example, thecarrier assembly30 may be rotatable about a vertical axis y. The x and y axis of the partial enclosure and the head assembly, respectively, are offset to provide orbital motion between the polishingarticle28 and thesubstrate carrier assembly30. Orbital motion is broadly described herein as an elliptical relative motion between the polishingarticle28 and thesubstrate carrier assembly30. Thesubstrate carrier assembly30 holds asubstrate22 with the deposition surface facing down towards the polishingarticle28. Alternatively, the polishingarticle28 may comprise a surface that may move in a translational or linear relative motion as well as rotatable, or circular rotational, relative motion to thesubstrate carrier assembly30.
• Thesubstrate carrier assembly30 generally includes adrive system68, ahead assembly78 and aseat assembly76. Thedrive system68 is generally coupled to theguide90 of thestanchion80. Thedrive system68 comprises acolumn70 that extends from apower head56 to support theseat assembly76. Thepower head56, which may be an electric or pneumatic motor, generally provides rotation to thecolumn70 along a central axis. Thedrive system86 additionally includes anactuator54 that is disposed within thecolumn70 and is coupled to thehead assembly78. Theactuator54, which may be a lead screw, pneumatic cylinder or other linear actuator, allows thehead assembly78 to move in relation to theseat assembly76.
• Theseat assembly76 generally includes a plurality ofgripper fingers74 disposed in a polar array about agripper plate72. Thegripper plate72 is coupled to thecolumn70 so that thegripper plate72 moves with thedrive system68. In one embodiment, threegripper fingers74 are provided. Thegripper fingers74 generally include abase member66, anextension64 and acontact finger62. Thecontact fingers62 are disposed at an angle to theextension64. Theextension64 is coupled to thebase member66. Thebase member66 is rotatably coupled to thegripper plate72. Thebase member66 generally includes an aperture that aligns with a hole in thegripper plate72. A clevis pin or other shaft member is disposed through the hole and aperture to allow rotation of thegripper finger74 in relation to thegripper plate72. Anactuator60 is coupled between theextension64 and thegripper plate72. Theactuator60 moves thegripper finger74 between an open and closed position. Aspring58 may be optionally disposed on the clevis pin to bias thegripper finger74 towards one position. When thecontact fingers62 are moved inward, anotch52 disposed at the ends of eachcontact finger62 defines a seat50 that is adapted to receive thesubstrate22 from a transfer robot (not shown). In the inward position, theextensions64 are disposed at a distance from each other that allows thesubstrate22 and robot to pass therebetween.
• FIG. 2 depicts one embodiment of thehead assembly78. Thehead assembly78 generally includes ahousing102, astem104, asupport plate106 and a plurality of substrate clamps120 (one of theclamps120 is shown). Generally, thehousing102 includes ahollow shaft128 coupled to theactuator54 at one end and terminating in aflange108 at the opposite end. Theflange108 has a downwardly extendinglip110 that defines acentral cavity112.
• Thesupport plate106 is disposed in thecentral cavity112. Thesupport plate106 has afirst side114 and asecond side116. Thesubstrate22 is generally disposed proximate thefirst side114 during processing. Thefirst side114 may additionally include one ormore vacuum ports118 disposed therein to restrain thesubstrate22 proximate thefirst side114.
• Thestem104 is coupled to asecond side116 of thesupport plate106. Thestem104 is generally orientated perpendicular to thesupport plate106. Thestem104 may include passages disposed therein to provide vacuum or fluid to thefirst side114 of thesupport plate108 or other portions of thehead assembly78.
• The substrate clamps120 are generally comprised of a conductive material, such as copper. The substrate clamps120 are coupled to aconductive ring122 that electrically couples the individual substrate clamps120. A screw typically fastens the substrate clamps120 to theconductive ring122 although other fasteners or fastening methods may be utilized. Theconductive ring122 generally includes a terminal124 to allow thering122 to be electrically biased by a power source (not shown) coupled to thering122 by a lead126 routed through thehousing102.
• Theconductive ring122 is secured to a mountingplate130 that is disposed in thecentral cavity112 between thehousing102 and thesupport plate106. The mountingplate130 is generally movable relative to thesupport plate106 so that the distance the substrate clamps120 extend beyond thefirst side114 of the support plate may be controlled. Generally, the mountingplate130 is biased away from thesupport plate106 by aspring132 disposed therebetween.
• To facilitate movement of the mountingplate130 and substrate clamps120, the mountingplate130 is coupled to asleeve134 that is movably disposed around thestem104. Thesleeve134 has afirst diameter portion136 that is sealed against thestem104 at one end by a seal such as an o-ring138. Thesleeve134 has a smaller,second diameter portion140 that interfaces with anarrower portion142 of thestem104. Thenarrower portion142 of thestem104 is sealed to thesleeve134 by an o-ring152, thus creating apiston chamber144 between thestem104 andsleeve134. As fluid, such as air, is applied or evacuated from thechamber144, the resulting force applied between thesleeve134 and stem104 causes thesleeve134 to move, thus correspondingly moving the substrate clamps120. Anouter portion146 of thesleeve134 is threaded and mates with a corresponding male threadedportion148 disposed in the mountingplate130. The amount of thread engagement between the mountingplate130 andsleeve134 may be adjusted to set the distance the substrate clamps120 protrude from thesupport plate106 at a predetermined amount. Aset screw150 in the mountingplate130 may be tightened to prevent the mountingplate130 from inadvertently turning about thesleeve134.
• FIG. 6 is cross sectional views of an alternative embodiment of anapparatus800 of the invention for electroless deposition, electroless polishing, or combinations thereof, of a material on the substrate surface. An electroless deposition does not normally require the presence of an anode for deposition of a material. Theapparatus800 discloses anenclosure834 that typically includes adiffuser plate844 and apolishing article828 disposed therein in acontact position820 withsubstrate822 disposed incarrier assembly830 described above inFIG. 1. The contact position may be defined as a distance between thesubstrate822 and the polishing article of about 100 μm or less.
• The polishingarticle828, such as theround polishing pad140 described herein, is disposed and supported in the electrolyte cell on thediffuser plate844. Thepartial enclosure834 can be a bowl shaped member made of a plastic such as fluoropolymers, TEFLON®, PFA, PE, PES, or other materials that are compatible with plating chemistries. Theenclosure834 generally defines a container or electrolyte cell in which an electrolyte or other polishing/deposition fluid can be confined. The electrolyte used in processing thesubstrate822 can include metals such as copper, nickel or other materials which can be electroless deposited onto a substrate.
• The electrolyte is circulated into and out of theenclosure834 to provide sufficient concentration of material to the substrate surface for processing. The electrolyte is typically provided to theenclosure834 via afluid delivery line840 having anoutlet842 positioned above the polishingarticle828. The electrolyte outlet from theenclosure834 is not shown. In one aspect, thepartial enclosure834 can be initially filled with electrolyte prior to substrate processing and can then circulate the electrolyte into and out of the partial enclosure.
• In operation, the polishingarticle28 is disposed in an electrolyte in theenclosure34. Thesubstrate22 on the carrier is disposed in the electrolyte and contacted with the polishing article. Electrolyte flow through the passages of the polishingarticle28 and is distributed on the substrate surface by thegrooves142. Conductive material, such as copper, in the electrolyte is then deposited by an electrochemical method, such as electroless deposition or electroplating. Thesubstrate22 and polishingarticle28 are rotated relative to one another polishing the substrate surface. A pressure between of about 2 psi or less is used between thesubstrate22 and the polishingarticle28.
• In an electroplating deposition process, a current in the range of about 0.5 amps to about 5 amps is applied to the substrate to deposit a seed layer or fill layer on the substrate adjacent to or in contact with the polishingarticle28. Additionally, the current my vary depending upon the features to be filled, and it is contemplated that a current of up to about 20 amps may be used to fill features. For example, the current may be applied by a pulse modulation, or pulse plating method, to enhanced voidless fill of high aspect ratios. The pulse plating method typically provides an electrical pulse modification technique including applying a constant current density over the substrate for a first time period, than applying a constant reverse current density over the substrate for a second time period, and repeating the first and second steps to fill the structure. After the structure has been filled using this pulse modulation process, a constant current density may be applied over the substrate to deposit a metal layer over the substrate. The pulse modulation process is more fully described in U.S. patent application Ser. No. 09/569,833 (Attorney Docket No. AMAT/003864), entitled “Electrochemical Deposition For High Aspect Ratio Structures Using Electrical Pulse Modulation”, filed on May 11, 2000, assigned to common assignee Applied Materials, Inc., and which is hereby incorporated by reference in its entirety to the extent not inconsistent with the invention.
• For an electroless deposition, the electrolyte is flowed through thepassages146 and distributed by thegrooves142 and exposed to a conductive material on the substrate surface that acts as a catalyst to deposit material on thesubstrate22. An example of an electroless deposition technique is more fully described in descriptions of the electroless deposition process in Chapter 31 ofModern Electroplating, F. Lowenheim, (3d ed.) and in U.S. Pat. No. 5,891,513, and in U.S. Pat. No. 6,258,223 (Attorney Docket No. 003698), filed on Jul. 9, 1999 and issued on Jul. 10, 2001, the latter assigned to common assignee Applied Materials, Inc., and which are hereby incorporated by reference in their entirety to the extent not inconsistent with the invention.
• FIG. 7 depicts one embodiment of aprocessing apparatus1000 having at least oneplating station1002 and at least one conventional polishing or buffingstation1006. One polishing tool that may be adapted to benefit from the invention is a MIRRA® chemical mechanical polisher available from Applied Materials, Inc. located in Santa Clara, Calif. Theexemplary apparatus1000 generally comprises afactory interface1008, aloading robot1010, and a depositing andplanarizing module1012, described asapparatus20 inFIG. 1. Generally, theloading robot1010 is disposed proximate thefactory interface1008 and the depositing andplanarizing module1012 to facilitate the transfer ofsubstrates22 therebetween.
• Thefactory interface1008 generally includes acleaning module1014 and one ormore wafer cassettes1016. Aninterface robot1018 is employed to transfersubstrates22 between thewafer cassettes1016, thecleaning module1014 and aninput module1020. Theinput module1020 is positioned to facilitate transfer ofsubstrates22 between the depositing andplanarizing module1012 and thefactory interface1008 by theloading robot1010. For example,unprocessed substrates22 retrieved from thecassettes1016 by theinterface robot1018 may be transferred to theinput module1020 where thesubstrates22 may be accessed by theloading robot1010 while processedsubstrates22 returning from the depositing andplanarizing module1012 may be placed in theinput module1020 by theloading robot1010.Processed substrates22 are typically passed from theinput module1020 through thecleaning module1014 before thefactory interface robot1018 returns the cleanedsubstrates22 to thecassettes1016. An example of such afactory interface1008 that may be used to advantage is disclosed in U.S. patent application Ser. No. 09/547,189 (Attorney Docket No. 003651), filed Apr. 11, 2000, which issued as U.S. Pat. No. 6,361,422 on Mar. 26, 2002, assigned to common assignee Applied Materials, Inc., and which is hereby incorporated by reference.
• Theloading robot1010 is generally positioned proximate thefactory interface1008 and the depositing andplanarizing module1012 such that the range of motion provided by therobot1010 facilitates transfer of thesubstrates22 therebetween. An example of aloading robot1010 is a 4-Link robot, manufactured by Kensington Laboratories, Inc., located in Richmond, Calif. Theexemplary loading robot1010 has agripper1011 that may orientate thesubstrate22 in either a vertical or a horizontal orientation.
• The exemplary depositing andplanarizing module1012 has atransfer station1022 and acarousel1034 in addition to theplating station1002 and the polishingstation1006, all of which are disposed on amachine base1026. The depositing andplanarizing module1012 may comprise one polishing module and two plating modules. Alternatively, the depositing andplanarizing module1012 may comprise one plating module and two polishing modules. In a further alternative, a polishing module1120 may be provided for polishing a substrate following processing by the methods described herein or in the apparatus described herein.
• In one embodiment, thetransfer station1022 comprises at least aninput buffer station1028, anoutput buffer station1030, atransfer robot1032, and aload cup assembly1024. Theloading robot1010 places thesubstrate22 onto theinput buffer station1028. Thetransfer robot1032 has two gripper assemblies, each having pneumatic gripper fingers that grab thesubstrate22 by the substrate's edge. Thetransfer robot1032 lifts thesubstrate22 from theinput buffer station1028 and rotates the gripper andsubstrate22 to position thesubstrate22 over theload cup assembly1034, then places thesubstrate22 down onto theload cup assembly1024. An example of a transfer station that may be used to advantage is described by Tobin in U.S. Pat. No. 6,156,124 (Attorney Docket No. 003651.02), which was filed Oct. 6, 1999 and issued Dec. 5, 2000, assigned to common assignee Applied Materials, Inc., and which is hereby incorporated by reference.
• Thecarousel1034 is generally described in U.S. Pat. No. 5,804,507 (Attorney Docket No. 00881D1), issued Sep. 8, 1998 to Tolles et al. and is hereby incorporated herein by reference in its entirety. Generally, thecarousel1034 is centrally disposed on thebase1026. Thecarousel1034 typically includes a plurality ofarms1036. Thearms1036 generally each supporting a polishinghead1038 while one arm supports acarrier head assembly1004. One of thearms1036 is shown in phantom such that thetransfer station1022 may be seen. Thecarousel1034 is indexable such that the polishinghead1038 andcarrier head1004 may be moved between themodules1002,1006 and thetransfer station1022.
• Generally the polishinghead1038 retains thesubstrate22 while pressing the substrate against a polishing material (not shown) disposed on the polishingstations1006. The polishingstation1006 generally rotates to provide a relative motion between thesubstrate22 retained by the polishinghead1038 and the polishing material. Typically, a polishing fluid is provided to assist in the material removal from thesubstrate22. One polishing head that may be utilized is a TITAN HEAD™ wafer carrier manufactured by Applied Materials, Inc., Santa Clara, Calif.
• FIG. 8 depicts a sectional view of the substratecarrier head assembly1004 supported above theplating station1006. In one embodiment, the substratecarrier head assembly1004 is substantially similar to thesubstrate carrier assembly30 described above and includinghead assembly78, aseat assembly76,enclosure34, and polishingarticle28 as shown inFIGS. 1 and 8. Similarly, theplating station1006 includes apartial enclosure1102 that defines an electrolyte cell to facilitate metal deposition on thesubstrate22 that is substantially similar to theenclosure30 described above. Theenclosure1102 of theplating station1006 is coupled to a motor that provides rotation of theenclosure1102.
• The arrangement of theplating stations1006 and polishingstations1002 on the depositing andplanarizing module1012 allow for thesubstrate22 to be sequentially plated or polishing by moving the substrate between stations. Thesubstrate22 may be processed in eachstation1002,1006 while remaining in it respective head orcarrier1038,1004, or the substrate may be switched between heads by offloading the substrate from one head into the load cup and loading the substrate into the other polishing head. Optionally, the depositing andplanarizing module1012 may comprise only one type of head may be utilized (i.e., all polishingheads1038 or all carrier heads1004).
• While foregoing is directed to various embodiments of the 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.

Claims (24)

1. An article of manufacture for depositing and planarizing a material on a substrate, comprising:

a polishing article having center portion and a perimeter portion defining a polishing surface;

a plurality of passages formed through the polishing article for flow of material therethrough; and

a plurality of grooves disposed in the polishing surface.

2. The article ofclaim 1, wherein at least one of the plurality of passages intersects with at least one of the plurality of grooves on the polishing surface.

3. The article ofclaim 1, wherein each of the passages has a diameter of between about 0.016 and about 0.5 inches and are disposed between about 0.1 inches and about 1.0 inches from one another.

4. The article ofclaim 1, wherein the plurality of grooves form a pattern comprising substantially circular concentric grooves, an X-Y pattern, or a triangular pattern on the polishing surface.

5. The article ofclaim 1, wherein a portion of the plurality of grooves are non-intersecting and are spaced between about 0.03 inches and about 0.3 inches apart.

6. The article ofclaim 1, wherein the polishing article is disposed on a perforated sub-pad.

7. The article ofclaim 6, wherein the perforated sub-pad comprises a plurality of pores disposed therein for flow of material therethrough and the plurality of pores of the perforated sub-pad and the plurality of passages in the polishing article are aligned for flow of material through the perforated sub-pad and the polishing article.

8. The article ofclaim 1, wherein the polishing article comprises a conductive material or a dielectric material having conductive elements disposed therein.

9. The article ofclaim 1, wherein the center portion is conductive and the perimeter portion is dielectric.

10. An article of manufacture for depositing and planarizing a material on a substrate, comprising:

a polishing article having a polishing surface and a plurality of holes disposed at least partially through the polishing article; and

a plurality of grooves disposed in the polishing surface, wherein an upper end of each of the plurality of holes is recessed below the polishing surface.

11. The article ofclaim 10, wherein the polishing surface is conductive.

12. The article ofclaim 10, wherein the polishing surface is a conductive polymer.

13. The article ofclaim 10, wherein the polishing surface comprises a dielectric portion and a conductive portion.

14. The article ofclaim 10, wherein the polishing article comprises a perimeter portion and a central opening, wherein the perimeter portion is dielectric and the central opening is adapted to receive one or more conductive elements.

15. The article ofclaim 10, wherein the plurality of grooves form a pattern comprising substantially circular concentric grooves, an X-Y pattern, or a triangular pattern on the polishing surface.

16. The article ofclaim 10, wherein a portion of the plurality of grooves are non-intersecting and are spaced between about 0.03 inches and about 0.3 inches apart.

17. The article ofclaim 10, wherein the polishing article is disposed on a perforated sub-pad.

18. A system for processing a substrate, comprising:

a platform having a rotating support;

a conductive layer coupled to the rotating support;

a polishing article coupled to the conductive layer with a sub-pad therebetween, the polishing article comprising:

a conductive polishing surface having a plurality of grooves formed therein, each of the plurality of grooves having a bottom, wherein a plurality of holes extend through the polishing article and intersects with the bottom of a portion of the plurality of grooves.

19. The system ofclaim 18, wherein the conductive polishing surface includes a conductive polymer.

20. The system ofclaim 18, wherein the sub-pad is dielectric.

21. The system ofclaim 18, wherein the plurality of grooves form a pattern comprising substantially circular concentric grooves, an X-Y pattern, or a triangular pattern on the polishing surface.

22. The system ofclaim 18, wherein a portion of the plurality of grooves are non-intersecting and are spaced between about 0.03 inches and about 0.3 inches apart.

23. The system ofclaim 18, wherein the polishing article comprises a conductive material or a dielectric material having conductive elements disposed therein.

24. The system ofclaim 18, wherein the sub-pad is perforated.

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