Chemical mechanical polishing slurry buildup cleaning

Abstract

A substrate polishing apparatus having a cleaning station mounted to a wall of a housing of the polishing apparatus. The cleaning station includes a nozzle movable relative to the wall, and the nozzle configured to spray a cleaning fluid. The apparatus also include an image sensor configured to generate an image of a surface of the polishing apparatus. A controller coupled to the nozzle is configured to direct the nozzle to the surface and configured to monitor slurry buildup on the surface using the image.

Description

CHEMICAL MECHANICAL POLISHING SLURRY BUILDUP CLEANING BACKGROUNDField

[0001] Embodiments of the present disclosure generally relate to chemical mechanical polishing (CMP) systems used in the manufacturing of semiconductor devices. In particular, embodiments herein relate to cleaning and monitoring slurry buildup in CMP systems.Description of the Related Art

[0002] Chemical mechanical polishing (CMP) is commonly used in the manufacturing of semiconductor devices to planarize or polish a layer of material deposited on a substrate surface. During a CMP process, a substrate is retained in a substrate carrier which presses the backside of the substrate towards a rotating polishing pad in the presence of a polishing fluid. Material is removed across the material layer surface of the substrate in contact with the polishing pad through a combination of chemical and mechanical activity which is provided by the polishing fluid and the relative motion of the substrate and the polishing pad.

[0003] Polishing fluid used in a CMP process may include an aqueous solution of one or more chemical constituents along with nanoscale abrasive particles suspended in the aqueous solution. Commonly, dried residues of the polishing fluid, such as agglomerations of abrasive particles, accumulate on component surfaces that are disposed above or otherwise proximate to the polishing pad during the polishing process. For example, dried residues of the polishing fluid often accumulate on surfaces of CMP system components that are disposed over a polishing pad as a polishing fluid is dispensed thereon, such as substrate carriers, pad conditioner assemblies, and / or fluid delivery arms. If the accumulated residue is not removed, agglomerations of abrasive particles may flake from the component surfaces onto the polishing pad and cause undesirable damage to the material surface of a substrate subsequently polished thereon. This damage often manifests as scratches, e.g., micro-scratches, on the substrate surface which may detrimentally affect the performance of a device formed thereon or in some circumstances, may render the device inoperable.

[0004] Unfortunately, removing the accumulated residue from component surfaces is generally laborious and time-consuming as the agglomerated abrasive particles often form cement-like layers. The result is undesirable extended and frequent polishing system downtime for consumable change-out and / or preventive maintenance procedures where the accumulated residue is manually cleaned from the component surfaces.

[0005] Accordingly, there is a need in the art for apparatus and methods that solve the problems described above.SUMMARY

[0006] The present disclosure generally relates to chemical mechanical polishing (CMP) systems used in the manufacturing of semiconductor devices. In particular, embodiments herein relate to cleaning and monitoring slurry buildup in CMP systems.

[0007] In one embodiment, a substrate polishing apparatus has a cleaning station mounted to a wall of a housing of the polishing apparatus. The cleaning station includes a nozzle movable relative to the wall, and the nozzle is configured to spray a cleaning fluid. The apparatus also include an image sensor configured to generate an image of a surface of the polishing apparatus. A controller coupled to the nozzle is configured to direct the nozzle to the surface and configured to monitor slurry buildup on the surface using the image.

[0008] In another embodiment, a slurry buildup cleaning method includes capturing an image of a surface of a polishing apparatus and determining an area in the image having slurry buildup. The method also includes driving a nozzle to spray cleaning fluid to clean the area, the nozzle coupled to a wall of a housing of the polishing apparatus.BRIEF DESCRIPTION OF THE DRAWINGS

[0009] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however,that the appended drawings illustrate only exemplary embodiments of the disclosure and are therefore not to be considered limiting of its scope, as the disclosure may admit to other equally effective embodiments.

[0010] Figure 1 is a schematic view of a polishing apparatus, according to one or more embodiments.

[0011] Figure 1A is a schematic, partial cross-sectional side view of Figure 1.

[0012] Figure 1B is a schematic, partial cross-sectional side view of Figure 1.

[0013] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.DETAILED DESCRIPTION

[0014] Embodiments of the present disclosure generally relate to chemical mechanical polishing (CMP) systems used in the manufacturing of semiconductor devices. In particular, embodiments herein relate to cleaning and monitoring slurry buildup in CMP systems.

[0015] Apparatus and / or methods disclosed herein provide cleaning and monitoring of slurry buildup on surfaces of a CMP tool. The polishing apparatus includes a cleaning station attached to a wall of the housing of the polishing apparatus. The cleaning station includes one or more nozzles mounted on a platform of the cleaning station. The nozzle is movable relative to the wall and can be driven toward different components or surfaces in the polishing apparatus. In some embodiments, the cleaning station includes a camera for monitoring slurry buildup on the components or surfaces. In some examples, the nozzle is advantageously driven to an area with slurry buildup based on images captured by the camera.

[0016] Figure 1 is a schematic view of a polishing apparatus 100, such as a chemical mechanical polishing (CMP) tool for processing one or more substrates. The polishing apparatus 100 includes a polishing platform, or base 102 that at leastpartially supports and houses a plurality of polishing stations 124. For example, the polishing apparatus 100 shown includes four polishing stations 124a, 124b, 124c and 124d. Each polishing station 124 is adapted to polish a substrate that is retained in a carrier head 126.

[0017] The polishing apparatus 100 also includes a plurality of carrier heads 126, each of which is configured to carry a substrate. The number of carrier heads can be a number equal to or greater than the number of polishing stations, e.g., four carrier heads or six carrier heads. For example, the number of carrier heads can be two greater than the number of polishing stations. This permits loading and unloading of substrates to be performed from two of the carrier heads while polishing occurs with the other carrier heads at the remainder of the polishing stations, thereby providing improved throughput.

[0018] The polishing apparatus 100 also includes a transfer station 122 for loading and unloading substrates from the carrier heads 126. The transfer station 122 can include a plurality of load cups 123, e.g., two load cups 123a and 123b, adapted to facilitate transfer of a substrate between the carrier heads 126 and a factory interface (not shown) or other device (not shown) by a transfer robot 110. The load cups 123 generally facilitate transfer between the robot 110 and each of the carrier heads 126.

[0019] The stations of the polishing apparatus 100, including the transfer station 122 and the polishing stations 124, can be positioned at substantially equal angular intervals around the center of the base 102. This is not required, but can provide the polishing apparatus 100 with a reduced footprint.

[0020] Each polishing station 124 includes a polishing pad 130 supported on a platen 120 (shown in Figures 1A-1B). For a polishing operation, one carrier head 126 is positioned at each polishing station 124. Two additional carrier heads can be positioned in the transfer station 122 to exchange polished substrates for unpolished substrates while the other substrates are being polished at the polishing stations

[0021] The carrier head 126 is adapted to hold a substrate against a polishing surface of the polishing pad 130, while relative motion is provided between the carrier head 126 and the platen 120 to polish the substrate. The relative motion may be rotational, lateral, or some combination thereof, and is provided by at least one of the carrier head 126 and the platen 120. Each carrier head 126 can have independent control of the polishing parameters, for example pressure, associated with each respective substrate.

[0022] The carrier heads 126 are held by a support structure that can cause each carrier head to move along a path that passes, in order, the first polishing station 124a, the second polishing station 124b, the third polishing station 124c, and the fourth polishing station 124d. This permits each carrier head to be selectively positioned over each of the polishing stations 124 and load cups 123.

[0023] In some implementations, each carrier head 126 is coupled to a carriage 108 that is mounted to an overhead track 128. By moving a carriage 108 along the overhead track 128, the respective carrier head 126 can be positioned over a selected polishing station 124 or load cup 123. A carrier head 126 that moves along the overhead track 128 traverses the path past each of the polishing stations 124.

[0024] In the implementation shown in Figure 1, the overhead track 128 has a circular configuration (shown in phantom) which allows the carriages 108 retaining the carrier heads 126 to be selectively orbited over and / or clear of the load cups 123 and the polishing stations 124. The overhead track 128 may have other configurations including elliptical, oval, linear or other suitable orientation. Alternatively, in some implementations (not shown) the carrier heads 126 are suspended from a carousel, and rotation of the carousel moves all of the carrier heads 126 simultaneously along a circular path. Although the polishing apparatus illustrated herein is outfitted with an overhead track, the present disclosure may utilize any suitable polishing apparatus. In one example, the polishing apparatus may have a robot which provides the same functionality as the overhead track.

[0025] Each polishing station 124 of the polishing apparatus 100 includes a spray bar 134 to dispense polishing fluid, such as abrasive slurry, onto the polishing pad 130 as shown in more detail in Figure 1A. Each polishing station 124 of thepolishing apparatus 100 includes a pad conditioning apparatus 112 to abrade the polishing surface 131 of the polishing pad 130 to maintain the polishing pad 130 in a consistent abrasive state as shown in more detail in Figure 1 B.

[0026] A controller 190, such as a programmable computer, is connected to respective motors to independently control the rotation rate of the platen 120 and the carrier heads 126 as described in more detail below. For example, each motor can include an encoder that measures the angular position or rotation rate of the associated drive shaft. Similarly, the controller 190 is connected to an actuator in each carriage 108 to independently control the lateral motion of each carrier head 126. For example, each actuator can include a linear encoder that measures the position of the carriage 108 along the overhead track 128.

[0027] The controller 190 includes a programmable central processing unit (CPU) 192, which is operable with a memory 194 (e.g., non-volatile memory) and support circuits 196. The support circuits 196 are conventionally coupled to the CPU 192 and comprise cache, clock circuits, input / output subsystems, power supplies, and the like, and combinations thereof coupled to the various components of the polishing apparatus 100.

[0028] In some embodiments, the CPU 192 is one of any form of general purpose computer processor used in an industrial setting, such as a programmable logic controller (PLC), for controlling various monitoring system component and subprocessors. The memory 194, coupled to the CPU 192, is non-transitory and is typically one or more of readily available memory such as random access memory (RAM), read only memory (ROM), floppy disk drive, hard disk, or any other form of digital storage, local or remote.

[0029] Herein, the memory 194 is in the form of a computer-readable storage media containing instructions (e.g., non-volatile memory), that when executed by the CPU 192, facilitates the operation of the polishing apparatus 100. The instructions in the memory 194 are in the form of a program product such as a program that implements the methods of the present disclosure (e.g., middleware application, equipment software application, etc.). The program code may conform to any one of a number of different programming languages. In one example, the disclosure maybe implemented as a program product stored on computer-readable storage media for use with a computer system. The program (s) of the program product define functions of the embodiments (including the methods described herein).

[0030] Illustrative computer-readable storage media include, but are not limited to: (i) non-writable storage media (e.g., read-only memory devices within a computer such as CD-ROM disks readable by a CD-ROM drive, flash memory, ROM chips or any type of solid-state non-volatile semiconductor memory) on which information is permanently stored; and (ii) writable storage media (e.g., floppy disks within a diskette drive or hard-disk drive or any type of solid-state random-access semiconductor memory) on which alterable information is stored. Such computer-readable storage media, when carrying computer-readable instructions that direct the functions of the methods described herein, are embodiments of the present disclosure.

[0031] Although illustrated as a single computer, the controller 190 could be a distributed system, e.g., including multiple independently operating processors and memories. The computer architecture is adaptable to various polishing operations based on programming of the controller 190 to control the order and timing that the carrier heads are positioned at the polishing stations.

[0032] For example, a mode of operation is for the controller to cause a substrate to be loaded into a carrier head 126 at one of the load cups 123, and for the carrier head 126 to be positioned in turn at each polishing station 124a, 124b, 124c and 124d so that the substrate is polished at each polishing station in sequence. After polishing at the last station, the carrier head 126 is returned to one of the load cups 123 and the substrate is unloaded from the carrier head 126.

[0033] Figure 1A is a schematic, partial cross-sectional side view of Figure 1 illustrating an exemplary spray bar 134 in combination with polishing station 124. The polishing apparatus 100 has a housing 101. The housing 101 generally includes the base 102, an upper wall 103, and a sidewall 104 between the base 102 and the upper wall 103. The base 102, upper wall 103, and sidewall 104 define a processing region 105 of the polishing apparatus 100.

[0034] The carrier head 126 has a housing 129. The carrier head 126 is coupled to the overhead track 128 which is coupled to a column 162 and which extends over the platen 120. A drive system 106 is coupled the carrier head 126 by a drive shaft 107. The drive system 106 provides at least rotational motion to the carrier head 126. The drive system 106 may also provide lateral motion to the carrier head 126 to impart a sweeping motion to the carrier head 126 relative to the platen 120, e.g., by driving the carriage 108 on the overhead track 128. The carrier head 126 is actuatable toward and away from the platen 120 such that a substrate 114 retained in the carrier head 126 may be disposed against the polishing pad 130 during polishing.

[0035] The platen 120 at each polishing station 124 is rotatable about an axis 121. For example, a motor 160 turns a drive shaft 123 to rotate the platen 120. The platen 120 is rotationally disposed on the base 102. A bearing 154 is disposed between the platen 120 and the base 102 to facilitate rotation of the platen 120 relative to the base 102.

[0036] In operation, the platen 120 is rotated about axis 121, and each carrier head 126 is rotated about a respective axis 127 and translated laterally across the polishing surface 131. The lateral sweep is in a direction parallel to the polishing surface 131. The lateral sweep can be a linear or arcuate motion.

[0037] Each spray bar 134 delivers polishing fluid, such as slurry 135, to an associated polishing pad 130 to facilitate the substrate polishing operation. In addition, the spray bar 134 can deliver a cleaning fluid, e.g., deionized water, to the polishing pad 130 to rinse polishing byproducts from the polishing surface 131. The spray bar 134 includes an arm 136 having a plurality of fluid dispensing ports (not shown) in a distal end for spraying fluid, such as slurry 135, onto the polishing surface 131 as shown in Figure 1A. A proximal end of the arm 136 is coupled to a base 138 which extends upward from the base 102 of the housing 101. The base 138 is rotatable to pivot the arm 136 between a first position disposed over the platen 120 (shown in Figure 1A) and a second position disposed adjacent the platen 120. During polishing, the spray bar 134 is located in the first position and slurry 135 is applied onto the polishing surface 131 as the platen 120 rotates.

[0038] The spray bar 134 is fluidly coupled to one or more fluid sources outside the processing region 105, such as slurry source 140 and deionized water source 142. Although only slurry and deionized water sources are illustrated, the spray bar 134 may utilize numerous additional fluid chemistries as known in the art. For example, other suitable fluid chemistries may include alcohols, amphiphilic compounds (e.g., detergents, soaps, lipoproteins, surfactants, synthetic amphiphiles, naturally-occurring amphiphiles), acids (e.g., citric acid, hydrogen peroxide), bases, oxidizing agents, reducing agents, hydrophilic compounds, hydrophobic compounds (e.g., oils, fats, waxes), or mixtures thereof.

[0039] Figure 1B is a schematic, partial cross-sectional side view of Figure 1 illustrating an exemplary pad conditioning apparatus 112 in combination with polishing station 124. The cross-sectional view of Figure 1B is taken at a different angle from that of Figure 1A, for example about 90 degrees apart. Each pad conditioning apparatus 112 includes an arm 113 which supports a conditioner head 115 over a respective platen 120. The arm 113 is rotatably secured to the base 102. A distal end of the arm 113 is coupled to a housing 116 of the conditioner head 115. A motor 117 is coupled to the distal end of the arm 113 for rotating the conditioner head 115 during pad conditioning. A proximal end of the arm 113 is coupled to a base 118 which extends upward from the base 102 of the housing 101. The base 118 is rotatable to pivot the arm 113 and laterally translate the conditioner head 115 across the polishing surface 131.

[0040] Each polishing station 124 of the polishing apparatus 100 includes a station cup 146 radially surrounding the platen 120. The station cup 146 has an inner sidewall surface 147 facing the platen 120. The inner sidewall surface 147 extends above the polishing surface 131. Slurry 135 from the polishing pad 130 contacts the inner sidewall surface 147 and collects inside the station cup 146. A drain 148 in the bottom of the station cup 146 and / or through the base 102 is used for draining slurry 135 collected inside the station cup 146.

[0041] In operation, buildup of slurry 135 may occur on surfaces inside the housing 101 due to incidental splashing, spraying, and / or aerosolization. For example, slurry 135 may buildup on surfaces of the carrier head 126, structuresabove the carrier head 126 such as the overhead track 128, the spray bar 134, the sidewall 104, the station cup 146, or the pad conditioning apparatus 112.

[0042] In order to facilitate cleaning of the slurry buildup on the surfaces inside the polishing apparatus 100, one or more cleaning stations 300 may be mounted on the upper wall 103 or the sidewalls 104 of the housing 101. As shown in Figures 1 and 1A-1B, a first cleaning station 300 is mounted on the upper wall 103, and a second cleaning station 300 is mounted on one of the sidewalls 104. Although two cleaning stations 300 are shown, the polishing apparatus 100 may be equipped with one, three, four or more cleaning stations. For example, additional cleaning stations 300 may be mounted to the other sidewalls 104.

[0043] In one embodiment, the cleaning station 300 includes one or more cleaning nozzles 310 for spraying a cleaning fluid toward various components or surfaces in the polishing apparatus 100. The cleaning stations 300 are in fluid communication with one or more cleaning fluid sources 302 (shown in Figure 1) to supply cleaning fluid to the one or more cleaning nozzles 310. The cleaning nozzle 310 may be supported on a platform 320 of the rinse station 300. In some embodiments, the platform 320 provides the cleaning nozzle 310 with up to six degrees of freedom such that the cleaning nozzle 310 may be directed to any surface in the housing 101 of the polishing apparatus 100. In one example, the platform 320 is a motorized platform having a motor for moving the nozzle 310. Although a single cleaning nozzle 310 is shown, each cleaning station 300 can includes from 1 to 8 nozzles, such as from 1 to 6 nozzles, such as from 1 to 2 nozzles, such as 1 nozzle, alternatively 2 nozzles, alternatively from 3 to 4 nozzles, such as 3 nozzles, alternatively 4 nozzles, alternatively 5 nozzles.

[0044] The cleaning nozzles 310 may be selected from spray nozzles, fan nozzles, cone nozzles, wash nozzles, or other suitable nozzle types. In some embodiments, the nozzles are whirl-type nozzles. In some embodiments, the nozzles have a spray angle of from about 30 degrees to about 120 degrees, such as about 30 degrees, alternatively about 60 degrees, alternatively about 90 degrees, alternatively about 120 degrees. In some embodiments, the nozzles have an orifice diameter of from about 1 / 32 inch to about 1 / 4 inch. When the cleaning station 300includes multiple nozzles 310, the nozzles 310 can have the same or different nozzle types.

[0045] In some embodiments, the nozzles 310 are formed from metal or plastic. In some embodiments, suitable metals include stainless steel (e.g., 303 or 316 stainless steel), brass, titanium, copper, nickel alloy, and alloys thereof. In some embodiments, suitable plastics include polyvinylchloride (PVC), chlorinated PVC, polypropylene, polytetrafluoroethylene, polyvinylidene fluoride, and combinations thereof.

[0046] In some embodiments, each cleaning station 300 can spray cleaning fluid to any component or surface of the polishing apparatus 100. In some embodiments, each cleaning stations 300 may have designated cleaning areas, such as designated components or surfaces in the polishing apparatus 100. In some embodiments, the cleaning areas of the cleaning stations 300 may at least partially overlap.

[0047] In some embodiments, the nozzles 310 may have different cleaning intensities or spray patterns. For example, one of the nozzles 310 on the same or different cleaning station 300 may be configured to provide a high velocity spray, and another nozzle 310 on the same or different cleaning station 300 may be configured to provide a low velocity spray. In some examples, one of the nozzles 310 on the same or different cleaning station 300 may have a larger diameter nozzle, and another nozzle 310 on the same or different cleaning station 300 may-have a smaller diameter nozzle. In some examples, a single cleaning station 300 may be used to spray two or more components, such as 3 or more components, such as 4 or more components. In some other embodiments, 2 or more cleaning stations 300 can be used to spray the same component, such as 2 or more stations spraying the same component, such as 3 or more stations spraying the same component, such as 4 or more stations spraying the same component.

[0048] In some embodiments, the cleaning fluid is a hydrophilic solution including at least one of water, an alcohol, an acid, a base, another hydrophilic substance, or combinations thereof. In some other embodiments the cleaning fluid is a hydrophobic solution including at least one of an oil, a fat, a wax, anotherhydrophobic substance, or combinations thereof. The cleaning stations 300 may spray the same or different cleaning fluids. One or more of the cleaning fluids may be stored in one or more cleaning fluid sources 302 in fluid communication with the cleaning stations 300.

[0049] In some embodiments, the cleaning station 300 may be equipped with one or more image sensors to monitor buildup of material in the polishing apparatus 100. In one example, the image sensor is a camera 330. The camera 330 may be mounted to the cleaning station 300 or at a standalone location. Like the nozzles 310, the camera 330 may be mounted on the platform 320 of the cleaning station 300, which provides the camera 330 with six degrees of freedom. In this respect, the one or more cameras 330 are movable relative to the polishing apparatus 100 for repositioning and / or re-orienting the camera 300 to change a field of view thereof. The position and orientation of the camera 330 enables imaging of any of the components or surfaces in the polishing apparatus 100. The image sensors, e.g., camera 330, are communicatively coupled to and controlled by to the controller 190, either wired or wireless. In some embodiments, the camera 330 uses a lens which is able to image an expanded field of view such as a wide-angle or fish-eye lens.

[0050] In some embodiments, the cleaning process is controlled programmatically, / .e., automatically, by the system controller 190. In some embodiments, the system controller 190 applies one or more predefined cleaning process routines. For example, the system controller 190 may sequentially clean the components and the walls of the polishing apparatus 100. In some embodiments, a cleaning process routine can include one or more parameters including, dispensing time for each cleaning station 300 or nozzle 310, dispensing sequence of each cleaning station 300 or nozzle 310, number of cycles for each cleaning station 300 or nozzle 310, delay time between cleaning station 300 or nozzle 310, respective flow rates of different cleaning fluids, and dispensing sequence of different cleaning fluids. For example, the cleaning process can include longer cleaning times than the predefined cleaning routine for areas have a higher tendency for slurry buildup.

[0051] In some embodiments, the system controller 190 programmatically determines parameters for the cleaning process based on a maintenance condition of the polishing apparatus 100 including without limitation, total runtime and runtime since last service, equipment lifespan, scheduled maintenance, error codes, repair requests, maintenance requests, and substrate processing performance and quality control. In some embodiments, the maintenance condition of the polishing apparatus 100 is determined using one or more image sensors, such as camera 330.

[0052] In some embodiments, the controller 190 determines, by use of an image sensor such as the camera 330, the presence of hot spots or residue buildup on one of a plurality of surfaces of the polishing apparatus 100. In response, the controller 190 may direct or drive the nozzle 310 toward the identified area of residue buildup or hot spot. When an area of residue buildup is identified, the controller 190 may be configured to store the location and recall the location for subsequent cleanings. During subsequent cleanings, the nozzles 310 may be driven to target the recalled area for additional or longer cleanings than the predefined clean time. In some embodiments, the controller 190 may determine a cleaning process to target the recalled area. In one example, the controller 190 may determine a periodic cleaning routine of the recalled area by the nozzle 310.

[0053] In some embodiments, the controller 190 determines, by use of an image sensor such as the camera 330, areas showing dryness ( / .e., no water droplet buildup). In response, the nozzles 310 may be driven by the controller 190 to wet or clean the dry area.

[0054] In some embodiments, the controller 190 generally includes a module configured to process images depicting an operating environment and identify, based on processing these images, whether an area in the operating environment is consistently clean or dirty (e.g., excessive slurry buildup). The images may be captured by the camera 330. In some aspects, the module may process images depicting an operating environment and determine whether areas in the operating environment are consistently clean and dirty based on an image processing machine learning model, such as a semantic segmentation model, and aggregatesegmentation maps over a plurality of images of the operating environment generated over time to identify areas in the operating environment that are consistently dirty. In some embodiments, the module may be configured to process images depicting an operating environment and identify, based on processing these images, whether an area in the operating environment is consistently dry or wet.

[0055] Segmentation generally allows for an image to be segmented into different classifications, with each classification being associated with a type of object (e.g., clean or dirty, wet or dry) within the environment. In some aspects, segmentation may be performed using semantic segmentation, which may be performed on a per-pixel basis to classify each pixel in the image to one of a plurality of classes (corresponding to classes of objects in an environment, for example). To do so, aspects of the present disclosure may pass image through a segmentation neural network in order to identify objects in the image. Generally, various object detection techniques can be used to identify different objects in the environment in order to generate a segmentation map in which the image is segmented into a plurality of classes associated with the identified objects in the environment. For example, object detection may be performed using various artificial neural networks, such as convolutional neural networks, attention-based neural networks, or other networks that can be used for such a task. In some aspects, a segmentation neural network may generate a segmentation map using instance segmentation techniques, which identifies and localizes objects in the environment captured in an image. A segmentation map generated by a segmentation neural network using instance segmentation techniques may thus include information identifying each object uniquely with the type of the object and an identifier differentiating different instances of a same type of object in the segmentation map.

[0056] A segmentation map illustrating the classifications of objects in an image may be output from the segmentation neural network. The segmentation neural network generally applies semantic segmentation to an image to identify objects in the image, and each class of object may be associated with a unique representation (e.g., color, pattern, etc.) in the segmentation map. Generally, the segmentation neural network may be a neural network trained to identify various objects inimages, such as a convolutional neural network, attention-based neural networks, or other neural networks that can perform object detection tasks.

[0057] Based on a segmentation map associated with each of a plurality of input images processed by a semantic segmentation model, areas in an environment depicted by the plurality of input images may be determined to be consistently clean or dirty. For example, for each unique segment within an image, a counter of times that a unique segment has been identified by the semantic segmentation model as an area that is dirty or depicts a dirty object may be maintained. If the counter for a segment in an image (corresponding to a specific area within the environment depicted by the plurality of input images) exceeds a threshold value (defined a priori as a static number, as a percentage of dirty instances across the plurality of input images, or the like), that segment may be determined to be consistently dirty, and one or more actions may be performed to adjust the cleaning of the area in the environment corresponding to that segment.

[0058] In some embodiments, a cleaning process may be scheduled or initiated to clean an area identified as consistently dirty (e.g., excessive slurry buildup). In some examples, areas identified as consistently dirty may be targeted for additional or longer cleaning. In one example, the targeted area may be cleaned using a higher velocity spray of cleaning fluid than a predefined velocity or a velocity for cleaning a consistently clean area. In another example, the targeted area mayreceive a longer cleaning cycle or shorter breaks between cleaning cycles. In some examples, a preset cleaning process may be modified in response to areas being identified as consistently dirty or clean. In one example, the clean time for areas that are consistently dirty is increased, and the clean time for areas that are consistently clean are decreased, while maintaining the same cleaning cycle time as the preset cleaning process.

[0059] In some embodiments, the nozzles 310 of the cleaning stations 300 may be manually controlled to clean a specific area. In one example, the camera 330 may be used as guide to direct the nozzles 310 to the specific area for cleaning. Because the nozzles 310 and the camera 330 are manually controllable, thecleaning station 300 advantageously enables manual cleaning of the polishing apparatus 100 without necessitating opening of the housing 101.

[0060] In some embodiments, the cleaning process may be configured to minimize cleaning fluid droplet size on the surface or the component being cleaned. In some examples, the flow rate of the cleaning fluid sprayed by the nozzle 310 can be modulated to control the droplet size. For example, at the start of the cleaning process, the cleaning fluid is supplied at a first flow rate to an initial cleaning. As the cleaning process continues, the flow rate may be reduced gradually or intermittently to a second flow rate to minimize the droplet size. In some embodiments, the camera 330 may be used to monitor the size of the droplet for different flow rates.

[0061] In some embodiments, the nozzles 310 may configured as a drying nozzle. In some examples, the nozzles 310 can spray a drying fluid such as nitrogen, air, or other suitable gas. In some embodiments, after spraying cleaning fluid to clean an area with slurry buildup, a nozzle can spray the drying fluid toward the area to remove the cleaning fluid. In some examples, the drying nozzle may be the same or different than the nozzle 310 that sprayed the cleaning fluid.

[0062] Although the disclosure herein relates to a polishing apparatus, it is contemplating the cleaning stations may be use with other chambers or components of a substrate processing system, including, cleaning chambers, robots, etc.

[0063] While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

Claims

What is claimed is:

1. A substrate polishing apparatus, comprising:a cleaning station mounted to a wall of a housing of the polishing apparatus, the cleaning station including a nozzle movable relative to the wall and configured to spray a cleaning fluid;an image sensor configured to generate an image of a surface of the polishing apparatus; anda controller coupled to the nozzle and configured to direct the nozzle to the surface and to monitor slurry buildup on the surface using the image.

2. The substrate polishing apparatus of claim 1, wherein the surface comprises a portion of at least one of a carrier head, an overhead track, a spray bar, a sidewall, a station cup, or a pad conditioning apparatus.

3. The substrate polishing apparatus of claim 1, wherein the image sensor is attached to or forms a part of the cleaning station.

4. The substrate polishing apparatus of claim 3, wherein the image sensor is movable relative to the wall.

5. The substrate polishing apparatus of claim 1, wherein the nozzle and the image sensor are attached to a platform of the cleaning station.

6. The substrate polishing apparatus of claim 1, wherein the wall is an upper wall or a side wall.

7. The substrate polishing apparatus of claim 1, wherein the cleaning station includes at least two nozzles.

8. The substrate polishing apparatus of claim 7, wherein the at least two nozzles have different sizes, shapes, or spray patterns.

9. The substrate polishing apparatus of claim 1, wherein the controller is configured to identify an area having slurry buildup in the polishing apparatus.

10. The substrate polishing apparatus of claim 9, wherein the nozzle is driven to clean the area for one or more of a longer time period than a predefined time period, spray a higher velocity cleaning fluid than a predefined velocity, or combinations thereof.

11. A slurry buildup cleaning method, comprising:capturing an image of a surface of a polishing apparatus;determining an area in the image having slurry buildup: anddriving a nozzle to spray cleaning fluid to clean the area, the nozzle coupled to a wall of a housing of the polishing apparatus.

12. The method of claim 11, wherein the surface comprises a portion of at least one of a carrier head, an overhead track, a spray bar, a sidewall, a station cup, or a pad conditioning apparatus.

13. The method of claim 11, wherein the nozzle is movably supported on a platform of cleaning station.

14. The method of claim 13, wherein the image is captured using an image sensor attached to or forming a part of the cleaning station.

15. The method of claim 11, wherein cleaning the area comprises cleaning the area for one or more of a longer period of time than a predefined time period, cleaning with a higher velocity fluid than a predefined velocity, using more than one cleaning fluid to clean the area, or combinations thereof.

16. The method of claim 11, wherein cleaning the area comprises sequentially cleaning the area using at least two or more nozzles.

17. The method of claim 16, wherein sequentially cleaning comprises spraying cleaning fluid at a first flow rate and then spraying cleaning fluid at a second flow rate.

18. The method of claim 17, further comprising monitoring a size of cleaning fluid droplet while cleaning the area.

19. The method of claim 11, further comprising determining a second area of interest being a dry area, and then cleaning the dry area.

20. The method of claim 19, wherein determining the second area of interest comprises determining the second area of interest being a dry area using the image of the surface.

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