Polishing system apparatus and method for reducing substrate edge defects - Patents.com

Abstract

Embodiments herein include a carrier loading station and associated methods that can be used to beneficially remove nanoscale and / or micron-scale particles adhered to the beveled edge of a substrate prior to polishing the substrate. By removing such contaminants, such as loosely adhered particles of dielectric material, from the beveled edge, contamination of the polishing interface can be avoided, thereby preventing and / or significantly reducing associated scratch-related defects.

Description

[Technical field]

[0001] FIELD OF THE DISCLOSURE

[0001] Embodiments herein relate generally to electronic device manufacturing, and more particularly to chemical mechanical polishing (CMP) systems and methods used in semiconductor device manufacturing processes. [Background technology]

[0002]

[0002] In the manufacture of high density integrated circuits, chemical mechanical polishing (CMP) is commonly used to planarize or polish layers of material deposited on a substrate. One common application of the CMP process in semiconductor device manufacturing is bulk film planarization, e.g., pre-metal dielectric (PMD) or inter-layer dielectric (ILD) polishing, where underlying two-dimensional or three-dimensional features form recesses and protrusions in the surface of the material to be planarized. Other common applications include shallow trench isolation (STI) and interlevel metallization, where the CMP process is used to remove vias, contacts, and trench fill (overburden) from the exposed surfaces (fields) of the layer of material where the STI or metallization features are located.

[0003] In a typical CMP process, a polishing pad is attached to a rotatable polishing platen, and a rotatable substrate carrier is used to press the material surface of the substrate against the polishing pad in the presence of a polishing fluid. A combination of chemical and mechanical action removes material across the surface of the substrate in contact with the polishing pad. The chemical and mechanical action is brought about by the polishing fluid, the relative motion of the substrate and polishing pad, and the downward force exerted on the substrate against the polishing pad.

[0004]

[0004] Unfortunately, undesirable contaminants introduced between the surface of the substrate and the polishing pad, i.e., at the polishing interface, can cause undesirable scratches on the substrate surface. One source of undesirable contaminants at the polishing interface is particles that are loosely attached to the surface of the beveled edge of the substrate being polished, such as flakes of dielectric material introduced during upstream manufacturing processes. During polishing of the substrate, flakes of these materials migrate from the beveled edge of the substrate to the polishing interface and cause nano- and micro-scratches on the substrate surface.

[0005]

[0005] Unlike other types of defects such as post-CMP residues, scratches permanently damage the substrate surface and cannot be removed by subsequent cleaning processes. For example, even light scratches extending across multiple lines of metal interconnects can cause traces of metal ions located therein to spread throughout the planarized material layer, thereby inducing leakage currents and time-dependent dielectric breakdown in the resulting semiconductor devices, affecting the reliability of the resulting devices. More severe scratches can cause undesirable kinks and bridges in adjacent metals and / or cause breaks and missing patterns on the substrate surface, undesirably causing shorts and ultimately leading to device failure, thereby reducing the yield of usable devices formed on the substrate. Similarly, scratches caused during STI CMP can affect the integrity of the gate oxide and cause its destruction, ultimately reducing device performance, reliability, and / or reducing yield.

[0006]

[0006] Therefore, there is a need in the art for a system and method that addresses the above-mentioned problems. Summary of the Invention

[0007]

[0007] Embodiments herein provide a carrier loading station and method that can be used to beneficially remove nanoscale and / or micron-scale particles adhered to the beveled edge of a substrate prior to polishing the substrate. By removing such contaminants, such as loosely adherent particles of dielectric material, from the beveled edge, contamination of the polishing interface can be avoided, thus preventing and / or significantly reducing scratch-related defects associated therewith.

[0008] In one embodiment, the polishing system includes a carrier loading station. The carrier loading station includes one or more support surfaces for supporting a polished substrate, a load cup, and a fluid delivery assembly disposed within the load cup. The one or more support surfaces are sized and positioned to engage a radially outermost portion of an active surface of the polished substrate. The fluid delivery assembly includes one or more first nozzles configured to direct energized fluid toward a peripheral edge of the polished substrate when the polished substrate is vacuum chucked to and aligned with a carrier head positioned above the carrier loading station.

[0009] In one embodiment, a method for processing a substrate is provided that includes transferring a substrate from a carrier loading station of a polishing system to a carrier head positioned over and aligned with the carrier loading station, rotating the carrier head and substrate about a carrier axis, using one or more first nozzles of the carrier loading station to direct energized fluid toward a peripheral edge of the substrate as the carrier head rotates the substrate about the carrier axis, moving the carrier head to a polishing station of the polishing system, and pressing the substrate against a polishing pad.

[0010]

[0010] In order that the above-mentioned features of the present disclosure may be understood in detail, the present disclosure summarized above will now be more particularly described with reference to embodiments, some of which are illustrated in the accompanying drawings. It should be noted, however, that the accompanying drawings merely depict exemplary embodiments and therefore should not be considered as limiting the scope of the present disclosure, which may admit of other equally effective embodiments. [Brief description of the drawings]

[0011] [Figure 1A] 1 is a schematic side view of an exemplary polishing system configured to perform the methods described herein. [Figure 1B] 1B is a schematic cross-sectional view of a substrate carrier of the polishing system shown in FIG. 1A. [Figure 2A] 1B is a schematic top view of an embodiment of a loading station that may be used with the polishing system of FIG. 1A. [Figure 2B] 2B is a schematic side view of the loading station shown in FIG. 2A taken along line 2B-2B. [Figure 3A] 1B is a schematic top view of another embodiment of a loading station that can be used with the polishing system of FIG. 1A. [Figure 3B] 3B is a schematic side view of the loading station shown in FIG. 3A taken along line 3B-3B. [Figure 4] 1 illustrates a method that may be used to remove contaminants from beveled edges of a substrate according to one embodiment. [Figure 5A] 5 is a schematic diagram illustrating the relationship between the nozzle and the edge of the substrate during the method according to FIG. 4. [Figure 5B] FIG. 5B illustrates the spray pattern of the nozzle shown in FIG. 5A. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012]

[0020] To facilitate understanding, wherever possible, the same reference numbers have been used to designate identical elements common to the figures. It is contemplated that elements and features of one implementation may be beneficially incorporated in other implementations without further recitation.

[0013]

[0021] FIELD OF THE DISCLOSURE

[0002] Embodiments herein relate generally to chemical mechanical polishing (CMP) systems, and in particular to head clean load / unload (HCLU) stations, herein carrier loading stations, for use with CMP systems and associated methods. The carrier loading stations and methods may be used to beneficially remove nanoscale and / or micron-scale particles attached to the beveled edge of a substrate prior to polishing the substrate. By removing such contaminants, e.g., loosely attached particles of dielectric material, from the beveled edge, contamination of the polishing interface may be avoided, thus preventing and / or significantly reducing scratch-related defects associated therewith.

[0014]

[0022] 1A is a schematic side view of an exemplary polishing system 100 that may be used to perform the methods described herein, including a base 101, multiple polishing stations 102 (one shown), a loading station 104, a carrier transport system 106, multiple carrier assemblies 108, and a system controller 110.

[0015]

[0023] The loading station 104 is used to receive and return substrates from a substrate handler 112, e.g., a robot having an end effector 114, and to load and unload substrates to and from individual ones of the carrier assemblies 108. Exemplary loading stations 200, 300 that may be used as the loading station 104 are further described in Figures 2A-2B and 3A-3B, respectively. The carrier transport system 106 may comprise any suitable system for supporting the multiple carrier assemblies 108 and moving the carrier assemblies 108 between the loading station 104 and one or more of the multiple polishing stations 102 for processing substrates thereon. Here, the carrier transport system 106 is shown as a pivot module that moves the multiple carrier assemblies 108 between the polishing stations 102 and the loading station 104 by pivoting the support arm 107 about axis A.

[0016]

[0024] The polishing station 102 includes a platen 116 having a polishing pad 118 mounted thereon, a fluid delivery arm 120, and a pad conditioner assembly 122. The platen 116 is rotatable about an axis B using an actuator 128 coupled thereto. The fluid delivery arm 120 is positioned above the platen 116 and is used to deliver a polishing fluid, such as a polishing slurry having an abrasive suspended therein, to the surface of the polishing pad 118. Typically, the polishing fluid contains other chemically active components, such as pH adjusters and oxidizers, to enable chemical mechanical polishing of the material surface of the substrate. The pad conditioner assembly 122 is used to press a fixed abrasive conditioning disk 124 against the polishing pad 118 before, after, or during polishing of the substrate to polish and regenerate the surface of the polishing pad 118 and remove polishing by-products.

[0017]

[0025] The carrier assemblies 108 are used to transport substrates in, out, and between individual polishing stations of the plurality of polishing stations 102 and to press the substrates against a rotating polishing pad in the presence of a polishing fluid, where each carrier assembly 108 includes a carrier head 130 (further described in FIGS. 1A-1B), a carrier shaft 132 coupled to the carrier head 130, and one or more actuators 136 coupled to the carrier shaft 132. The one or more actuators 136 are used to rotate the carrier head 130 about a carrier axis C, to sweep the carrier head 130 between the inner and outer radii of the polishing pad 118, and simultaneously exert a force against a back (non-active) surface of a substrate 138 on which the carrier head 130 is disposed.

[0018]

[0026] An exemplary carrier head 130 is illustrated generally in cross-sectional view in FIG. 1B. In FIG. 1B, carrier head 130 is shown in a loading mode with a substrate 138 vacuum-chucked therein. Here, carrier head 130 includes a housing 140 and a base assembly 142 that is movably and sealingly coupled to housing 140 and defines therewith a load chamber 144. The downward force exerted on base assembly 142 and the relative position of housing 140 and base assembly 142 are controlled by pressurizing or evacuating gas therefrom, e.g., by applying a vacuum to load chamber 144.

[0019]

[0027] The base assembly 142 includes a carrier base 146, a substrate backing assembly 147 movably and sealingly coupled to the carrier base 146 and collectively defining a chamber 158, and an annular retaining ring 154 surrounding the substrate backing assembly 147 and movably coupled to the carrier base 146. The substrate backing assembly 147 includes a flexible membrane 148 and a membrane backing plate 150 having a plurality of apertures 152 formed therethrough. The membrane backing plate 150 is sealingly coupled to the carrier base 146 by a first actuator 156a, e.g., an annular membrane or bladder, disposed therebetween, and the flexible membrane 148 is coupled to the membrane backing plate 150. During substrate polishing, the chamber 158 is pressurized such that the flexible membrane 148 exerts a downward force on the backside surface of the substrate 138 as the carrier head 130 rotates to press the substrate 138 against the polishing pad 118.

[0020]

[0028] When polishing is completed, or during a substrate loading step, the substrate 138 is chucked to the carrier head 130 by applying a vacuum to the chamber 158, causing the surface of the flexible membrane 148 that contacts the backside of the substrate 138 to deflect upward. The upward deflection of the flexible membrane 148 creates a low pressure pocket between the flexible membrane 148 and the substrate 138, thereby vacuum-chucking the substrate to the carrier head 130. The membrane backing plate 150 provides rigid support for the substrate 138, limiting the upward movement of the flexible membrane 148 and substrate 138 during vacuum chucking, and maintaining the shape of the flexible membrane 148.

[0021]

[0029] The retaining ring 154 is coupled to the carrier base 146 using a second actuator 156b, e.g., an annular flexible membrane or bladder. During substrate polishing, the retaining ring 154 surrounds the substrate 138, and a downward force on the retaining ring 154 prevents the substrate 138 from slipping off the carrier head 130 as the polishing pad 118 moves underneath. The downward forces exerted on the retaining ring 154 and the substrate 138 are independently controlled to allow fine tuning of the polishing conditions at the substrate edge. Similarly, the relative positions of the retaining ring 154 and the membrane backing plate 150, e.g., the offset in the Z direction between them, can be independently controlled using respective actuators 156a,b coupled thereto. This controllable offset determines the amount of recession and / or protrusion P of the substrate 138 relative to the retaining ring 154 when the substrate 138 is vacuum-attached to the carrier head 130. In some embodiments, the controllable recess or protrusion P of the substrate 138 relative to the retaining ring 154 is advantageously used to facilitate cleaning of the beveled surface of the substrate 138, as described in the methods below.

[0022]

[0030] Operation of the polishing system 100 is facilitated by a system controller 110 (FIG. 1A). The system controller 110 includes a programmable central processing unit (CPU) 160, which is operable with memory 162 (e.g., non-volatile memory) and support circuits 164. The support circuits 164 are conventionally coupled to the CPU 160 and include cache, clock circuits, input / output subsystems, power supplies, etc., and combinations thereof coupled to the various components of the polishing system 100, thereby facilitating control of substrate processing operations.

[0023]

[0031] The CPU 160 is one of any form of general-purpose computer processor used in industrial environments, such as a programmable logic controller (PLC), for controlling various system components and sub-processors. The memory 162 coupled to the CPU 160 is a form of computer-readable storage medium (e.g., non-volatile memory) that is non-transient and includes instructions that, when executed by the CPU 160, facilitate the operation of the polishing system 100. The instructions in the memory 162 are in the form of a program product, such as a program that performs the method of the present disclosure. The program code may conform to any one of a number of different programming languages. In one embodiment, the present disclosure may be implemented as a program product stored in a computer-readable storage medium for use with a computer system. The program(s) of the program product define the functions of the embodiments (including the methods described herein). Thus, a computer-readable storage medium becomes an embodiment of the present disclosure when it carries computer-readable instructions that direct the functions of the methods described herein.

[0024]

[0032] Figure 2A is a schematic top view of a loading station 200 according to one embodiment that may be used in place of loading station 104 of Figure 1A. Figure 2B is a schematic cross-sectional view of loading station 200 taken along line 2B-2B of Figure 2A. To reduce visual clutter, at least some of the features shown in Figure 2A are not shown in Figure 2B, and vice versa.

[0025]

[0033] The loading station 200 includes a cup assembly 202, a pedestal assembly 204, and a fluid delivery assembly 206. The cup assembly 202 includes a load cup 212 disposed on a first shaft 214 and an actuator 216 coupled to the first shaft 214 and used to move the load cup 212 in the Z direction, i.e., toward and away from a carrier head (not shown) positioned thereon. The load cup 212 includes an annular upper 218 and a lower housing 220 that together define a collection area 222 for collecting fluids used during the carrier and substrate cleaning methods described herein. Fluids are drained therefrom using a drain 224 fluidly coupled to the collection area 222.

[0026]

[0034] The top portion 218 includes one or more carrier alignment features, here annular lip 226, extending upwardly from and located proximate a periphery of the top portion 218. During transfer of a substrate (shown in phantom in FIG. 2B ) to and from a carrier head (not shown), the load cup 212 is in a raised position and the annular lip 226 surrounds a portion of the outwardly facing surface of the carrier head to facilitate alignment between the carrier head and the load cup 212.

[0027]

[0035] The pedestal assembly 204 includes a pedestal 228 disposed on a second shaft 230 and an actuator 232 coupled to the second shaft 230 and used to move the pedestal in the Z direction. The pedestal 228 has a generally circular shape when viewed from above and has an annular lip 238 disposed proximate to a peripheral edge of the pedestal 228 and extending upwardly therefrom. The annular lip 238 is sized and positioned to engage the radially outermost portion of the active surface of the substrate 138, thereby supporting the substrate 138 away from a concave surface 240 of the pedestal 228 and minimizing contact with and avoiding scratches associated therewith with devices fabricated thereon.

[0028]

[0036] The pedestal is movable in the Z direction relative to the load cup 212 and can extend upwardly from and retract into the load cup 212 to provide access to the end effector 114 (FIG. 1A) of the substrate handler 112 and facilitate loading and unloading of substrates from a carrier head positioned thereon. Here, the pedestal 228 has a number of openings 242 disposed therethrough and a number of notches 244a disposed around its periphery. The top 218 of the load cup 212 includes a number of corresponding notches 244b formed in its radially inwardly facing surface that are aligned with the number of notches 244a formed in the edge of the pedestal. The number of openings 242 and notches 244a,b enable the fluid supply assembly 206 disposed thereunder to direct fluid toward a desired surface of a carrier head (and / or a vacuum chucked substrate) positioned above and aligned with the load station 200.

[0029]

[0037] The fluid supply assembly 206 is fixedly coupled to the load cup 212 and includes one or more first nozzles 250a (three shown), one or more second nozzles 250b (three shown), and a number of third nozzles 250c. The one or more first nozzles 250a and the one or more second nozzles 250b are aligned (when viewed from above) with openings formed by the notches 244a,b. In some embodiments, the one or more first nozzles 250a and the one or more second nozzles 250b are used to direct cleaning fluid toward and remove polishing by-products from an annular gap disposed between a flexible membrane and a retaining ring of a rotating carrier head.

[0030]

[0038] The one or more first nozzles 250a are fluidly coupled to a first fluid source 252a and positioned to direct a first fluid toward the peripheral edge of the substrate when the substrate is placed on the rotating carrier head positioned above the loading station 200. The first fluid is used to remove undesired contaminants, such as nanoparticles or microparticles of dielectric material, from the beveled surface of the substrate prior to polishing. Examples of suitable fluids that may be used as the first fluid with the one or more first nozzles 250a include deionized water (DIW), pressurized gas, such as nitrogen (N2) or clean dry air (CDA), fluidized ice particles of DIW or carbon dioxide (CO2) and / or solutions containing such ice particles, and combinations thereof.

[0031]

[0039] Here, the one or more first nozzles 250a are positioned to direct a first fluid towards the beveled edge of a substrate disposed on a rotating substrate carrier. The first fluid may be emitted from the one or more first nozzles 250a in a continuous or pulsed pressurized jet or stream, and / or may be acoustically excited (e.g., via acoustic cavitation), pneumatically excited (e.g., using a liquid mixed with a pressurized gas), thermally excited (e.g., steam), or combination(s) thereof. In some embodiments, the one or more first nozzles 250a are fluidly coupled to a first fluid source 252a through a manifold 254a that distributes the first fluid therebetween.

[0032]

[0040] Acoustically exciting the first fluid includes ultrasonic or megasonic excitation of the first fluid. For example, one or both of the first nozzle 250a and the first fluid source 252a may be configured with an acoustic generator 256, e.g., a piezoelectric transducer, operable in a frequency range from a low ultrasonic range (e.g., about 20 KHz) to a high megasonic range (e.g., about 2 MHz). Other frequency ranges may also be used.

[0033]

[0041] Pneumatically exciting the first fluid includes emitting different phase components from the one or more first nozzles 250a, such as one or more of liquid and / or solid phase materials, e.g., DIW, a solution containing fluidized ice particles, and / or floating ice particles, and a pressurized gas, such as N2 or CDA. The different phase components can be combined in the first fluid source 252a or can be separately supplied to and combined with the one or more first nozzles 250a. For example, in some embodiments, the one or more first nozzles 250a can be atomizer nozzles, and the pressurized gas separately supplied thereto includes an atomizing gas.

[0034]

[0042] Thermally exciting the first fluid includes heating the first fluid to a vapor or gas phase, e.g., saturated or supersaturated steam. For example, in some embodiments, the first fluid provided to the one or more first nozzles 250a includes water vapor or steam having a temperature in a range of about 80° C. to about 150° C., e.g., about 100° C. to about 120° C., at a pressure in a range of about 30 psig to about 140 psig, e.g., about 40 psig to about 50 psig.

[0035]

[0043] The one or more second nozzles 250b are fluidly coupled to a second fluid source 252b through a second manifold 254b that is used to distribute the second fluid among the one or more second nozzles. The one or more second nozzles are aligned and positioned (when viewed from above) on corresponding sides of the notches 244a,b so as to be interleaved with the one or more first nozzles 250a around the periphery of the pedestal 228. The one or more second nozzles 250b are aligned with the loading station 200 and positioned to direct the second fluid to a peripheral edge of a substrate disposed on a rotating carrier head disposed thereon. Typically, the second fluid 250b comprises a rinsing liquid such as DIW that is maintained at or below ambient temperature, e.g., below about 40° C. or near a range of about 20° C. to about 40° C. The second fluid emitted by one or more second nozzles 250b may be used to wash away contaminants dislodged by the excited first fluid and / or to cool the edge of the substrate and the surface of the carrier head heated by the excited first fluid.

[0036]

[0044] The plurality of third nozzles 250c are disposed radially inward (with respect to the load cup 212) of the one or more first nozzles 250a and the one or more second nozzles 250b and are aligned (when viewed from above) with the opening 242. The plurality of third nozzles 250c are used to direct a third fluid toward the active surface of a substrate disposed on the rotating carrier head or toward a flexible membrane of the rotating carrier head between substrates. The plurality of third nozzles 250c are in fluid communication with a third fluid source 252c through a third manifold 254c. The third fluid is used to rinse the active surface of a substrate disposed on the rotating carrier head and / or the flexible membrane of the rotating carrier head before and / or after the polishing process. The third fluid may include a cleaning liquid and / or a rinsing agent such as DIW, which are applied in combination or sequentially.

[0037]

[0045] The nozzles 250a-c described herein are configured to provide any one or combination of fluid spray patterns, such as a flat fan, a hollow cone, a full cone, a solid stream, or combinations thereof. In some embodiments, one or both of the first nozzle 250a and the second nozzle 250b are configured to deliver a flat fan spray pattern.

[0038]

[0046] Figure 3A is a schematic top view of another embodiment of a loading station 300 that may be used in place of the loading station 104 of Figure 1A. Figure 3B is a schematic cross-sectional view of the loading station 300 taken along line 3B-3B of Figure 3A. To reduce visual clutter, at least some of the features shown in Figure 3A are not shown in Figure 3B, and vice versa.

[0039]

[0047] The loading station 300 includes a cup assembly 302 and a fluid delivery assembly 306 disposed therein. The cup assembly 302 includes a load cup 312 disposed on a shaft 314 and an actuator 316 coupled to the shaft 314 and used to move the load cup 312 in the Z direction, i.e., toward and away from a carrier head (not shown) positioned thereon. The load cup 312 includes an annular upper portion 318 and a lower housing 320 that together define a collection area 322 for collecting fluids used during the carrier and substrate cleaning methods described herein. Fluids are drained therefrom using a drain 324 fluidly coupled to the collection area 322.

[0040]

[0048] The top 318 includes a plurality of carrier alignment features 326, an annular lip 338 disposed proximate a radially inward edge of the top, and a plurality of substrate alignment features 340. The plurality of carrier alignment features 326 extend upwardly from an upwardly facing surface of the top 318 and are spaced apart proximate a periphery thereof. During transfer of a substrate (shown in phantom in FIG. 3B ) to and from a carrier head (not shown), the load cup 312 is in a raised position and the plurality of alignment features 326 contact a radially outward surface of the carrier head to facilitate alignment between the carrier head and the load cup 312.

[0041]

[0049] The annular lip 338 is sized and positioned to engage the radially outermost portion of the active surface of the substrate 138 (shown in dotted lines in FIG. 3B ) to minimize contact with devices fabricated thereon and avoid associated scratches. The annular lip 338 extends upwardly from the top portion 318 to space the substrate 138 from that surface to facilitate transfer of the substrate to and from a carrier head (not shown) positioned above the loading station 300. A number of substrate alignment features 340 are disposed adjacent and radially outwardly from the annular lip 338 and are used to center the substrate 138 on the annular lip 338 when the substrate 138 is received from the substrate handler 112. Typically, the plurality of substrate alignment features 340 are recessed within the load cup 312 so as not to interfere therewith during carrier loading and unloading.

[0042]

[0050] The top 318 of the load cup 312 includes one or more notches 344 (three shown) formed in its radially inward surface that are aligned (when viewed from above) with one or more edge cleaning nozzles 350a of the fluid supply assembly 306 disposed therebelow. The one or more edge cleaning nozzles 350a are fluidly coupled to a first fluid source 352a and positioned to direct a first fluid toward the peripheral edge of the substrate when the substrate is placed on a rotating carrier head positioned above the loading station 300. Here, the edge cleaning nozzles 350a, first fluid source 352a, and first fluid are substantially similar to the first nozzles 250a, first fluid source 252a, and first fluid described in FIGS. 2A-2B and may include any one or combination of features thereof. In some embodiments, the fluid supply assembly 306 further includes one or more second nozzles (not shown) fluidly coupled to a second fluid source (not shown), which may be substantially similar to the one or more second nozzles 250b fluidly coupled to the second fluid source 252b shown and described in Figures 2A-2B.

[0043]

[0051] Here, the fluid supply assembly 306 further includes a plurality of third nozzles 350c disposed radially inward (with respect to the load cup 312) of the one or more edge cleaning nozzles 350a. The plurality of third nozzles 350c are used to direct a third fluid toward an active surface of a substrate disposed on the rotating carrier head or toward a flexible membrane of the rotating carrier head positioned thereon. The plurality of third nozzles 350c are in fluid communication with a third fluid source 352c through a manifold 354. The third nozzles 350c, the third fluid source 352c, and the third fluid are substantially similar to the third nozzles 250c, the third fluid source 252c, and the third fluid described in FIGS. 2A-2B and may include any one or combination of features and / or characteristics thereof.

[0044]

[0052] FIG. 4 illustrates a method 400 for cleaning the beveled edge of a substrate using the loading stations 200, 300 described herein.

[0045]

[0053] At step 402, the method 400 includes transferring a substrate 138 from a carrier loading station 104 of the polishing system 100 to a carrier head 130 positioned thereon. In some embodiments, transferring the substrate 138 includes positioning the carrier head 130 over the carrier loading station 104 at step 404, moving one or both of the loading station 104 and the carrier head 130 toward one another at step 406, aligning the carrier head 130 and the carrier loading station 104 at step 408, and vacuum chucking the substrate 138 to the carrier head at step 410.

[0046]

[0054] At step 412, the method 400 includes rotating the carrier head 130, and thus the substrate 138 vacuum-chucked thereto, about the carrier axis B. Concurrent with step 412, step 414 of the method 400 includes using one or more first nozzles 250a, 350a of the carrier loading station 104 to direct the excited fluid toward the periphery of the substrate 138.

[0047]

[0055] At step 416, the method 400 includes moving the carrier head 130 to the polishing station 102. At step 418, the method 400 includes pressing the substrate against the polishing pad 118.

[0048]

[0056] 5A, one or more first nozzles 250a and / or one or more second nozzles 250b (not shown) are positioned to direct excited fluid 501 or rinsing liquid towards a peripheral edge, e.g., a beveled edge, of the substrate 138. In some embodiments, one or more of the nozzles 250a,b are spaced apart (in the Z direction) from the substrate 138 by a distance X of about 20 cm or less, e.g., about 15 cm or less.

[0049]

[0057] In some embodiments, such as those shown diagrammatically in Figures 5A-5B, one or more of the first nozzles 250a and / or one or more of the second nozzles 250b (not shown) are configured to deliver a substantially flat fan-shaped spray pattern toward the periphery of the substrate 138. Typically, in those embodiments, the nozzles 250a and / or 250b are positioned such that the flat portion 501a (Figure 5A) of the spray pattern is generally tangential to the peripheral edge of the substrate 132e and forms an angle 503 of about 60° to about 120° with the substrate surface, i.e., within 30° of the perpendicular, e.g., within 20° of the perpendicular, within 10° of the perpendicular, etc., where the fan-shaped portion 501b (Figure 1B) of the spray pattern forms an angle 505 of about 60° to about 120°.

[0050]

[0058] Advantageously, the above-described carrier loading station and method can be used to remove nano-scale and / or micron-scale particles attached to the beveled edge of the substrate prior to polishing the substrate. By removing such contaminants, such as loosely attached particles of dielectric material from the beveled edge, contamination of the polishing interface can be avoided, thus preventing and / or significantly reducing scratch-related defects associated therewith.

[0051]

[0059] While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the present disclosure may be devised without departing from the basic scope thereof, as determined by the following claims.

Claims

1. 1. A polishing system comprising:

1. A carrier loading station, comprising: one or more support surfaces for supporting a substrate to be polished, the support surfaces being sized and positioned to engage a radially outermost portion of an active surface of the substrate to be polished; Road Cup and a carrier head including a substrate backing assembly and an annular retaining ring surrounding the substrate backing assembly; a fluid supply assembly secured directly to the load cup, the fluid supply assembly including one or more first nozzles configured to spray an energized fluid in a fan shaped spray pattern having a flattened portion directed toward an annular gap formed between the substrate backing assembly and the annular retaining ring when the carrier head is positioned over and aligned with the carrier loading station; a carrier loading station including: A polishing system, wherein when the polished substrate is vacuum chucked to the carrier head positioned above and aligned with the carrier loading station, the flat portion of the fan-shaped spray pattern contacts the peripheral edge of the polished substrate, and the excited fluid comprises an acoustically excited fluid, a liquid mixed with a pressurized gas, a thermally excited fluid, or a combination thereof.

2. The polishing system of claim 1 , wherein the one or more first nozzles are disposed proximate to the one or more support surfaces when the carrier loading station is viewed from above.

3. The polishing system of claim 1 , wherein the one or more first nozzles are atomizer nozzles.

4. 2. The polishing system of claim 1, wherein the one or more first nozzles are positioned such that the flat portion of the fan shaped spray pattern is within 20 degrees of an orthogonal to the effective surface of the polished substrate.

5. The polishing system of claim 1 , wherein the one or more first nozzles are fluidly coupled to a first fluid source configured to supply the energized fluid to the one or more first nozzles.

6. The method further comprises a non-transitory computer readable medium having instructions stored thereon for performing a method for processing a substrate, the method comprising: transferring a substrate from the carrier loading station to the carrier head, the carrier head being positioned over and aligned with the carrier loading station; rotating the carrier head and the substrate about a carrier axis; using the one or more first nozzles to direct the excited fluid toward the periphery of the substrate as the carrier head rotates the substrate about the carrier axis; moving the carrier head to a polishing station of the polishing system; pressing the substrate against a polishing pad; The polishing system of claim 1 .

7. Transferring the substrate to the carrier head comprises: positioning the carrier head over the carrier loading station, the substrate being disposed on one or more support surfaces of the carrier loading station; moving one or both of the carrier loading station and the carrier head toward one another; aligning the carrier head and the carrier loading station using one or more carrier alignment features extending upwardly from the carrier loading station; vacuum chucking the substrate to the carrier head using the substrate backing assembly; The polishing system of claim 6 .

8. 7. The polishing system of claim 6, wherein the one or more first nozzles are spaced from the substrate by a distance of 20 cm or less when the energized fluid is directed toward the peripheral edge of the substrate.

9. The polishing system of claim 6, wherein the fluid supply assembly further includes one or more second nozzles fluidly coupled to a second fluid source, the one or more second nozzles positioned to direct rinsing liquid from the second fluid source toward the peripheral edge of the substrate as the carrier head rotates about the carrier axis.

10. The polishing system of claim 6, wherein the substrate backing assembly is surrounded by the annular retaining ring and when the excited fluid from the one or more first nozzles is directed toward the peripheral edge of the substrate, a surface of the vacuum chucked substrate protrudes outward from the annular retaining ring.

11. A method for processing a substrate, comprising the steps of: transferring a substrate from a carrier loading station of a polishing system to a carrier head positioned above and aligned with said carrier loading station; rotating the carrier head and the substrate about a carrier axis; when the carrier head is positioned on and aligned with the carrier loading station, spraying an excited fluid in a fan shaped spray pattern having a flat portion directed toward an annular gap formed between a substrate backing assembly and an annular retaining ring using one or more first nozzles fixed directly to the carrier loading station, the flat portion of the fan shaped spray pattern contacting a peripheral edge of the substrate as the carrier head rotates the substrate about the carrier axis, the excited fluid comprising an acoustically excited fluid, a liquid mixed with a pressurized gas, a thermally excited fluid, or a combination thereof; moving the carrier head to a polishing station of the polishing system; pressing the substrate against a polishing pad; The method includes:

12. Transferring the substrate to the carrier head comprises: positioning the carrier head over the carrier loading station, the substrate being disposed on a surface of the carrier loading station; moving one or both of the carrier loading station and the carrier head toward one another; aligning the carrier head and the carrier loading station using one or more carrier alignment features extending upwardly from the carrier loading station; vacuum chucking the substrate to the carrier head using a substrate backing assembly; The method of claim 11 , comprising:

13. The method described in claim 12, wherein the one or more first nozzles are spaced from the substrate by a distance of 20 cm or less when the excited fluid is directed toward the peripheral edge of the substrate.

14. 12. The method of claim 11, further comprising using one or more second nozzles of the carrier loading station to direct rinsing liquid to the peripheral edge of the substrate as the carrier head rotates about the carrier axis.

15. from the one or more first nozzles The method of claim 11 , wherein the excited fluid is acoustically excited, pneumatically excited, thermally excited, or a combination thereof.

16. The method of claim 15 , wherein the one or more first nozzles are atomizer nozzles.

17. 13. The method of claim 12, wherein the substrate backing assembly is surrounded by the annular retaining ring, and a vacuum chucked surface of the substrate protrudes outwardly from the annular retaining ring as the excited fluid from the one or more first nozzles is directed toward the peripheral edge of the substrate.

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