Modular chemical mechanical polisher for simultaneous polishing and pad treatment

Abstract

The present disclosure is directed to a polishing module for performing chemical mechanical polishing of a substrate. The substrate can be a semiconductor substrate. The described polishing module has multiple pads, such as polishing pads, arranged in a single polishing station. The pads are configured to remain stationary during processing, such as during a polishing or buffing process. Either an XY gantry assembly or a head actuation assembly is coupled to the polishing module system body and configured to move a carrier head over the pads. Between processing steps, the polishing pads can be aligned so that a new polishing pad is exposed to the carrier head.

Description

[Technical Field]

[0001] FIELD OF THE INVENTION The embodiments described herein relate generally to apparatus used in the manufacture of electronic devices, and more particularly to a modular chemical mechanical polishing (CMP) system that may be used to polish or planarize the surface of a substrate in a semiconductor device manufacturing process. [Background technology]

[0002] Chemical-mechanical polishing (CMP) is commonly used to planarize or polish material layers deposited on substrates during the manufacture of high-density integrated circuits. In a typical CMP process, a substrate is held in a carrier head, which presses the backside of the substrate against a polishing pad fixed to the surface of a rotating platen. A combination of chemical and mechanical action, brought about by the polishing fluid and the relative motion between the substrate and the polishing pad, removes material across the surface of the material layer of the substrate that contacts the polishing pad. Typically, after one or more CMP processes are completed, the polished substrate will be further processed in one or more post-CMP substrate processing steps. For example, the polished substrate may be further processed using one or a combination of cleaning, inspection, and metrology steps. Once post-CMP processing is complete, the substrate can be sent from the CMP processing area to a subsequent device manufacturing process, such as a lithography, etch, or deposition process.

[0003] To conserve valuable manufacturing floor space and reduce manufacturing costs, CMP systems typically include a first section, e.g., a rear section, that includes multiple polishing stations, and a second section, e.g., a front section, that is integrated with the first section to form a single polishing system. The first section may include one or a combination of a post-CMP cleaning station, an inspection station, and / or a pre-CMP or post-CMP metrology station. The first section of a CMP system can often be customized during manufacturing to specifically address the needs of a particular device customer.

[0004] The first part of a conventional CMP system is often too complex and takes up too much valuable manufacturing floor space for maximum substrate throughput. One reason for the low throughput is that the polishing process is stopped during a process used to clean and / or recondition the polishing pad after multiple polishing processes have been performed on the polishing pad. However, if sufficient cleaning and / or reconditioning time is not provided, it has been found that defect levels on substrates increase due to concerns about cross-contamination and polishing defects. Therefore, the cleaning and / or reconditioning time limits the total throughput of substrates passing through the CMP system. As such, the throughput density of the CMP system (i.e., the number of substrates processed per unit time per unit area of ​​manufacturing floor space) is undesirably limited by the performance of the cleaning and / or reconditioning process, which in turn limits the number of polishing modules available for processing in a typical CMP system configuration.

[0005] Therefore, what is needed in the art is a modular polishing system that can solve the problems described herein while providing improved substrate throughput density. Summary of the Invention

[0006] The present disclosure generally relates to chemical mechanical polishing (CMP) modules and customizable, high-throughput density modular CMP systems comprising same. Embodiments herein are directed to modular polishing systems comprising stacked polishing modules, which provide increased system throughput density and improved reliability compared to conventional polishing systems.

[0007] An embodiment of the present disclosure includes a substrate polishing system including a plurality of polishing stations positioned in a stacked arrangement. Each of the polishing stations includes a system body, the system body including one or more walls defining a processing region, a platen, and a head assembly. The platen is disposed within the processing region of the system body and has a rectangular pad support surface configured to accommodate a non-axisymmetric polishing pad, with a long side of the rectangular pad support surface aligned in a first direction. A carrier head is disposed above the pad support surface of the platen. The head assembly includes a carrier head disposed above the pad support surface of the platen, a linear actuator connected to a center rail support, and a support arm connecting the carrier head to the linear actuator, the linear actuator configured to position the carrier head and the support arm in the first direction. Embodiments may include one or more of the following features. The substrate polishing system may include a substrate polishing system in which the linear actuator is the only means for generating relative motion between the carrier head and the non-axisymmetric polishing pad mounted on the rectangular pad support surface. Implementations of the described techniques may include hardware, a method or process, or computer software on a computer-accessible medium.

[0008] One general aspect of the present disclosure includes a substrate polishing system. The substrate polishing system also includes a system body including one or more walls defining a processing region. The system also includes a first platen disposed within the processing region of the system body. The system also includes a second platen disposed within the processing region of the system body. The system also includes a center rail support disposed within the processing region of the system body between the first platen and the second platen. The system also includes a first head assembly disposed above one of the first platen or the second platen, the first head assembly may include a first carrier head and a first support arm coupling the first carrier head to the center rail support, and a second head assembly disposed above one of the first platen or the second platen, the second head assembly may include a second carrier head and a second support arm coupling the second carrier head to the center rail support.

[0009] Embodiments of the present disclosure may further include a substrate polishing system including multiple polishing stations positioned in a stacked arrangement. The substrate polishing system may include a first polishing station configured to be positioned above a second polishing station. Each of the polishing stations includes a system body including one or more walls defining a processing region, a platen, and a head assembly. The platen is disposed within the processing region of the system body and has a rectangular upper surface. The head assembly is disposed above the platen. An XY gantry assembly is disposed above the platen and configured to operate both the head assembly and the slurry module in one or more predetermined patterns in the X and Y directions while the platen is in a first position. The system may further include a pad conditioner.

[0010] Embodiments of the present disclosure may further include a polishing station configured for use during semiconductor manufacturing. The polishing station includes a first polishing module including a system body including one or more walls defining a processing region, a first platen disposed within the processing region of the system body, a second platen disposed within the processing region of the system body, a carrier head within the processing region of the system body, and an XY gantry assembly disposed above the first and second platens, the XY gantry assembly configured to move the carrier head in one or more predetermined patterns in the X and Y directions while both the first and second platens are in fixed positions relative to the system body. The system may further include one or more pad conditioners within the processing region of the system body.

[0011]

[0003] Embodiments of the present disclosure may further include a polishing station configured for use during semiconductor manufacturing. The polishing station includes a system body including one or more walls defining a processing region, a first platen disposed within the processing region of the system body, a second platen disposed within the processing region of the system body, a center rail support disposed within the processing region of the system body, a first head assembly disposed above one of the first platen or the second platen, and a second head assembly disposed above one of the first platen or the second platen. The first head assembly includes a first carrier head and a first support arm coupling the first carrier head to the center rail support. The second head assembly includes a second carrier head and a second support arm coupling the second carrier head to the center rail support. The first head assembly may further include a first rotating shaft positioned at an inner end of the first support arm opposite the first carrier head, and the second head assembly may further include a second rotating shaft positioned through an inner end of the second support arm opposite the second carrier head.

[0012] Embodiments of the present disclosure may further include systems comprising a computer configured to perform specific steps or actions by installing software, firmware, hardware, or a combination thereof on the system that causes the system to perform specific actions during the steps. One or more computer programs may be configured to perform specific steps or actions by including instructions that, when executed by a data processing device, cause the device to perform one or more actions described herein. Other embodiments of this aspect include corresponding computer systems, devices, and computer programs stored on one or more computer storage devices, each configured to perform the actions of one or more methods described herein.

[0013] So that the features of the present disclosure described above may be understood in detail, a more particular description of the present disclosure briefly summarized above will be had by reference to embodiments, some of which are illustrated in the accompanying drawings. It should be noted, however, that the accompanying drawings depict only exemplary embodiments and therefore should not be considered as limiting the scope of the present disclosure, as other equally effective embodiments may also be permitted. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a schematic plan view of a modular polishing system including one or more polishing stations according to one embodiment. [Figure 2A] 1 is a schematic cross-sectional side view of a polishing system according to one embodiment. [Figure 2B] 2B is an enlarged side cross-sectional view of the polishing station illustrated in FIG. 2A according to one embodiment. [Figure 2C] 2C is a schematic top partial cross-sectional view of the polishing station of FIG. 2B according to one embodiment. [Figure 3A] 1 is a schematic cross-sectional side view of another polishing station according to one embodiment. [Figure 3B]3B is an enlarged side cross-sectional view of the polishing station illustrated in FIG. 3A according to one implementation. [Figure 3C] 3C is a schematic top partial cross-sectional view of the polishing station of FIG. 3B according to one embodiment. [Figure 4A] 1 is a schematic cross-sectional side view of another polishing station according to one embodiment. [Figure 4B] 4B is an enlarged side cross-sectional view of the polishing station illustrated in FIG. 4A according to one embodiment. [Figure 4C] 4C is a schematic top partial cross-sectional view of the polishing station of FIG. 4B according to one embodiment. [Figure 5] 1 is a schematic top partial cross-sectional view of yet another polishing station according to one embodiment. [Figure 6] 1 is a schematic cross-sectional side view of a polishing station according to one embodiment. [Figure 7] 1 is a schematic cross-sectional side view of another polishing station according to one embodiment. [Figure 8A] 1 is a schematic cross-sectional side view of a polishing station according to one embodiment. [Figure 8B] 8B is a schematic top partial cross-sectional view of the polishing station of FIG. 8A according to one embodiment. [Figure 9A-B] FIG. 1 is a schematic diagram of a multi-pad platen assembly according to one embodiment. [Figure 10] FIG. 2 is a flow diagram illustrating a method of using a polishing station according to embodiments described herein. DETAILED DESCRIPTION OF THE INVENTION

[0015] Wherever possible, identical reference numerals have been used to facilitate understanding by indicating identical elements common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.

[0016] FIELD OF THE DISCLOSURE Embodiments of the present disclosure generally relate to chemical mechanical polishing (CMP) systems used in semiconductor device manufacturing. In particular, embodiments herein are directed to a modular polishing system comprised of vertically stacked polishing modules, which provides increased system throughput density and improved reliability compared to conventional polishing systems.

[0017] In some embodiments, the throughput of a CMP system is increased, at least in part, by simultaneously performing multiple CMP processing steps, while maximizing the throughput density of the CMP system and preventing a dramatic increase in system complexity due to an increase in the number of polishing pad assemblies used to process substrates. The embodiments of the disclosure provided herein utilize a fixed platen and polishing pad assembly to perform one or more polishing processes within each polishing module. The fixed platen and polishing pad assembly remain stationary during polishing steps. In some steps, a first pad is used to polish a substrate while a second pad is cleaned or conditioned. The second pad can be positioned adjacent to the first pad, for example, on the opposite side of the platen. Between processing steps, the first and second pads can be simultaneously indexed to swap positions.

[0018] In some embodiments described herein, a polishing station is configured for simultaneous polishing and ex-situ conditioning, where a first polishing pad is configured to polish a substrate and a second polishing pad is configured to be conditioned and cleaned in a cleaning zone. Once polishing of a substrate is completed, a belt coupled to the first and second polishing pads is used to move the second polishing pad to a processing zone for polishing another substrate or to continue polishing the same substrate, while the first polishing pad is moved to a cleaning zone for conditioning and cleaning. In some embodiments, the first and second polishing pads are configured differently to facilitate a multi-step process. In one example, a substrate is pressed against the first polishing pad during a first polishing step, a belt moves the second polishing pad to a processing zone, and a substrate is pressed against the second polishing pad during a second polishing step. In some embodiments, the first polishing pad and the second polishing pad are configured to have one or more material or physical properties that differ from one another.

[0019] Generally, polishing a substrate involves pressing a material surface of the substrate against a polishing pad in the presence of a polishing liquid. The material surface is pressed against the polishing pad by applying a downward force to the backside (inactive surface) of the substrate while moving the substrate relative to the polishing pad. Here, the downward force on the substrate and the relative motion between the substrate and the polishing pad are substantially provided by movement of the substrate carrier assembly and the first actuator assembly relative to the polishing pad.

[0020] The substrate carrier assembly can include a carrier head and a pneumatic assembly fluidly coupled to the carrier head. The pneumatic assembly provides pressurized gas and / or vacuum to the carrier head for use during polishing and chucking (e.g., substrate holding) operations. In other embodiments, the carrier assembly includes one or more electromechanical actuators configured to perform some or all of the functions described in connection with the pneumatic assembly.

[0021] The first actuator assembly is configured to support a substrate carrier assembly over the upward-facing surface of the platen and move the substrate carrier assembly in a direction parallel to the platen, thereby providing relative motion between a substrate disposed in the carrier head and a stationary polishing pad disposed therebelow. In some embodiments, the first actuator assembly is positioned over an upward-facing polishing pad, herein referred to as the first polishing pad, in a processing region between the platen assembly and the system body. The first actuator assembly is configured to move the substrate carrier assembly and the polishing liquid distribution system relative to a surface of the first polishing pad facing the processing region. The second actuator assembly is configured to move the pad conditioning assembly and the pad cleaning system relative to a surface of the second polishing pad facing the cleaning region.

[0022] 1 is a schematic plan view of a modular polishing system 100 including one or more polishing stations 115. The polishing stations 115 may be any one of the polishing stations 200 of FIGS. 2A, 2B, and 2C, the polishing stations 300 of FIGS. 3A, 3B, and 3C, the polishing stations 400 of FIGS. 4A, 4B, and 4C, the polishing stations 600 of FIGS. 5 and 6, the polishing stations 700 of FIGS. 5 and 7, or the polishing stations 800 of FIGS. 8A and 8B.

[0023] Here, the modular polishing system 100 is characterized by a first portion 120 and a second portion 105 coupled to the first portion 120. The second portion 105 includes one or more polishing stations 115, each including one or more polishing modules. The one or more polishing stations 115 include a structural support 111 for holding and supporting the polishing modules within the one or more polishing stations 115. Each of the one or more polishing stations 115 includes at least a transfer station 116 for placing one or more substrates 180 within the one or more polishing stations 115. As described in FIGS. 2A-8B, each of the one or more polishing stations 115 further includes one or more platens adapted to receive one or more polishing pads thereon. A polishing head for polishing the substrates is also disposed within each polishing station 115.

[0024] FIG. 2A is a schematic cross-sectional view of the polishing station 200. The polishing station 200 includes multiple polishing modules 250a, 250b, 250c, and 250d. FIG. 2B is an enlarged side view of a polishing module of the polishing station 200. FIG. 2C is a schematic partial cross-sectional top view of the polishing station shown in FIG. 2B. In some embodiments, there is a first polishing module 250a, a second polishing module 250b, a third polishing module 250c, and a fourth polishing module 250d. Each of the first polishing module 250a, the second polishing module 250b, the third polishing module 250c, and the fourth polishing module 250d is similar and includes similar components for processing substrates. Multiple polishing modules 250a, 250b, 250c, 250d can be stacked vertically, which allows the polishing station 200 to have a significantly smaller footprint than conventional CMP tools that have two or more polishing modules or polishing areas arranged on a single plane. The polishing station 200 also provides improved substrate throughput density.

[0025] Typically, first section 120 includes one or a combination of a plurality of system loading stations 122, one or more substrate handlers, e.g., first robot 124 and second robot 126, one or more metrology stations 128, one or more location-specific polishing (LSP) modules 130, and one or more post-CMP cleaning systems 132. LSP module 130 is typically configured to polish only a portion of the substrate surface using a polishing member (not shown) having a surface area smaller than the surface area of ​​the substrate being polished. LSP module 130 is often used to refine a relatively small portion of the substrate after the substrate has been polished in the polishing module, i.e., to remove additional material from the small portion. In some embodiments, one or more LSP modules 130 may be included in second section 105 instead of or coupled to one of the polishing modules.

[0026] In other embodiments, one or more LSP modules 130 may be arranged in any other desired configuration within the modular polishing system described herein. For example, one or more LSP modules 130 may be arranged between the first section 120 and the second section 105, between adjacently arranged polishing modules in any of the configurations described herein, and / or near any end of the second section described herein, where each end of the second section is distal from the first section. In some embodiments, the modular polishing system may include one or more buffing modules (not shown), which may be arranged in any of the configurations described above for the LSP modules 130. In some embodiments, the first section 120 features at least two post-CMP cleaning systems 132, which may be arranged on either side of the second robot 126.

[0027] The post-CMP cleaning system 132 facilitates removal of residual polishing fluids and polishing by-products from the substrate 180 and may include any one or a combination of a brush or spray box 134 and a drying unit 136. The first robot 124 and the second robot 126 are used in combination to transfer the substrate 180 between the second section 105 and the first section 120, including between these various modules, stations, and systems. For example, here, the second robot 126 is used at least to transfer the substrate between the transfer station 116, one or more metrology stations, the LSP module 130, the brush or spray box 134, and the drying unit 136.

[0028] In embodiments herein, operation of the modular polishing system 100 is directed by a system controller 170. The system controller 170 includes a central processing unit (CPU) 171, which is operable with memory (non-volatile memory) 172 and support circuits 173. The support circuits 173 are connected to the CPU 171 and include cache, clock circuits, input / output subsystems, power supplies, etc., and combinations thereof, which are connected to and facilitate control of the various components of the modular polishing system 100. The CPU 171 is one of any form of general-purpose computer processor used in industrial settings, such as a programmable logic controller (PLC), to control the various components and sub-processors of a processing system. The memory 172 is connected to the CPU 171 and is typically one or more of readily available memory, such as random access memory (RAM), read-only memory (ROM), a floppy disk drive, a hard disk, or any other form of local or remote digital storage.

[0029] Typically, memory 172 takes the form of a non-transitory computer-readable storage medium (e.g., non-volatile memory) containing instructions that, when executed by CPU 171, facilitate operation of modular polishing system 100. The instructions in memory 172 take the form of a program product, such as a program that implements the methods of the present disclosure. The program code may conform to any one of several different programming languages. In one example, the present disclosure may be implemented as a program product stored on a computer-readable storage medium for use with a computer system. The program of the program product defines the functions of embodiments (including the methods described herein).

[0030] Exemplary non-transitory computer-readable storage media include, but are not limited to, (i) non-writable storage media on which information is permanently stored (e.g., a read-only memory device in a computer, such as a CD-ROM disk readable by a CD-ROM drive, a flash memory, a ROM chip, or any type of solid-state non-volatile semiconductor memory (e.g., a solid state drive (SSD))), and (ii) writable storage media on which changeable information is stored (e.g., a floppy disk in a diskette drive or hard disk drive, or any type of solid-state random access semiconductor memory). Such computer-readable storage media, when carrying computer-readable instructions that direct the functions of the methods described herein, become embodiments of the present disclosure. In some embodiments, the methods described herein are performed by one or more application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other types of hardware implementations. In some other embodiments, the substrate processing and / or handling methods described herein are performed by a combination of software routines, ASICs, FPGAs, and / or other types of hardware implementations. One or more system controllers 170 may be used with one or any combination of the various modular polishing systems described herein and / or with individual polishing modules of such a polishing system.

[0031] Polishing Module Each of the polishing modules 250a, 250b, 250c, and 250d includes a system body 202, a first platen 238a disposed within the system body 202, a second platen 238b disposed within the system body 202, a carrier head assembly 210, an XY gantry assembly 204 disposed above the first platen 238a and the second platen 238b within the system body 202, a liquid supply unit 212, and one or more pad conditioners 214. The enclosed area within the system body 202 includes a processing space 226 defined by a plurality of inner sidewalls 202A-202F of the system body 202. The inner sidewalls 202A-202F include an upper inner sidewall 202A, a bottom inner sidewall 202B opposite the upper inner sidewall 202A, a first inner sidewall 202C disposed between the upper inner sidewall 202A and the bottom inner sidewall 202B, a second inner sidewall 202D opposite the first inner sidewall 202C, a third inner sidewall 202E, and a fourth inner sidewall 202F. The upper inner sidewall 202A may also be referred to as the ceiling of the system body 202. The first platen 238a, the second platen 238b, the carrier head assembly 210, the XY gantry assembly 204, the liquid supply unit 212, and one or more pad conditioners 214 are each disposed within the processing space 226.

[0032] Liquid supply unit 212 may be a slurry supply module configured to supply slurry and / or one or more processing fluids (e.g., one or more liquids 234 in FIG. 2B ) to the upper surfaces of pads 236 a, 236 b mounted on platens 238 a, 238 b. In some embodiments, pads 236 a, 236 b are polishing pads, such as substrate polishing pads or semiconductor substrate polishing pads. In the embodiment of FIGS. 2A-2C , liquid supply unit 212, carrier head assembly 210, and pad conditioner 214 are each coupled to xy gantry assembly 204, which is configured to enable movement of carrier head assembly 210, pad conditioner 214, and liquid supply unit 212, respectively, in both the x and y directions. In some embodiments, movement of the carrier head assembly 210, pad conditioner 214, or liquid supply unit 212 in both the x and y directions is produced using one or more actuators (e.g., pneumatic or electromechanical actuators) configured to provide the desired movement of these components. Thus, various actuators in the XY gantry assembly 204 and components in the system controller 170 enable relative movement of the liquid supply unit 212, carrier head assembly 210, and pad conditioner 214 with respect to the first platen 238 a, second platen 238 b, and the first and second pads 236 a, 236 b mounted thereon, respectively.

[0033] 2B , the xy gantry assembly 204 is configured to actuate the carrier head assembly 210, the pad conditioner 214, and the liquid supply unit 212 in the x and y directions, respectively. The xy gantry assembly 204 includes one or more cross beams 228, 230 and a plurality of runway beams 224. In some embodiments, the cross beams 228, 230 are referred to as bridge girders or bridge rails, and the cross beams 228, 230 form a bridge between two runway beams 224. The cross beams 228, 230 are positioned above or inserted into the runway beams 224 such that the cross beams 228, 230 are supported by the runway beams 224. In the embodiment described herein, there are two cross beams 228, 230, e.g., a first cross beam 228 and a second cross beam 230.

[0034] The first cross beam 228 is coupled to and configured to support and actuate one or both of the liquid supply unit 212 and the carrier head assembly 210. The second cross beam 230 is coupled to and configured to support and actuate the pad conditioner 214. In some embodiments, the first cross beam 228 supports the carrier head assembly 210, the pad conditioner 214, and the liquid supply unit 212. In other embodiments, the carrier head assembly 210, the pad conditioner 214, and the liquid supply unit 212 are each mounted on a separate cross beam 228, 230 or set of cross beams 228, 230, and there are three cross beams 228, 230. In embodiments in which the carrier head assembly 210, pad conditioner 214, and liquid supply unit 212 are each mounted on a separate cross beam 228, 230, there may be three or more cross beams 228, 230. Each of the cross beams 228, 230 may represent a set of adjacent, parallel cross beams 228, 230 configured to carry a trolley for movement along the cross beam 228, 230. A driver and / or actuator may be coupled to at least one end of the cross beams 228, 230. As shown in FIGS. 2A-2B , the driver or actuator is configured to move the cross beams 228, 230 in a first direction (e.g., the +x direction and the −x direction) along the runway beam 224.

[0035] The carrier head assembly 210 is coupled to one of the cross beams 228, 230 of the XY gantry assembly 204. The carrier head assembly 210 includes a carrier head trolley frame 240 that couples a carrier head 244 to the XY gantry assembly 204. As shown in FIGS. 2A-2B, the carrier head 244 is positioned in the xy plane above the carrier loading station 268 (FIG. 2C). In FIG. 2C, the carrier head 244 is positioned in the xy plane above the polishing pad 236a. The carrier head assembly 210 is sometimes referred to herein as the polishing head assembly, and the carrier head 244 is sometimes referred to herein as the polishing head. The carrier head trolley frame 240 is configured to support the carrier head 244 and move the carrier head 244 in a second direction (e.g., the +y direction and the −y direction) along the cross beam 228. A vertical actuator 242 is disposed between the carrier head 244 and the carrier head trolley frame 240 such that the vertical actuator 242 is configured to move the carrier head 244 in a third direction (e.g., the +z direction and the -z direction) relative to the carrier head trolley frame 240 and the xy gantry assembly 204.

[0036] The vertical actuator 242 can be a hydraulic actuator and can be connected to one or more pneumatic assemblies, such as the electrical or pneumatic components 216. Slides or rails within the vertical actuator 242 are used to slidably couple the carrier head 244 to the trolley frame 240. The carrier head 244 is configured to hold one or more substrates during the polishing process. The carrier head 244 can lift the substrate from a support surface within the system body 202, such as one of the pads 236 a, 236 b. The carrier head 244 is also configured to apply backside pressure to the substrate to press the substrate against the pads 236 a, 236 b. As briefly mentioned above, the carrier head 244 includes a retaining ring that surrounds the substrate during polishing and one or more flexible components, such as a bladder, diaphragm, or membrane layer (not shown), which, together with other components of the carrier head 244, can define a chamber disposed therein. The flexible components of the carrier head 244 and the chambers defined by the flexible components are useful for both substrate polishing and substrate loading and unloading processes. To enable the substrate loading and polishing processes, respectively, negative and positive pressures are provided to the chambers using gas supplied by a pneumatic assembly. For example, pressurization can be applied to the chambers defined by one or more flexible components to urge a substrate disposed within the carrier head toward a polishing pad by pressing components of the carrier head against the backside of the substrate. When polishing is complete or during the substrate loading process, a substrate can be vacuum-chucked to the carrier head 244 by applying a vacuum to the same or another chamber to deflect upward a membrane layer in contact with the backside of the substrate. The upward deflection of the membrane layer creates a low-pressure pocket between the membrane and the substrate, thereby vacuum-chucking the substrate to the carrier head 244. During a substrate unloading step, when the substrate is unloaded from the carrier head 244 to the carrier loading station 268 (FIG. 2C), pressurized gas may be introduced into the chamber.Pressurized gas in the chamber deflects the membrane downward, releasing the substrate from carrier head 244 into carrier loading station 268. In some embodiments, carrier head 244 is described as a carrier head. A combination of chemical and mechanical action provided by the polishing fluid, the downward force on the substrate, and the relative motion between the substrate and polishing pad removes material from the surface of the substrate opposite the pad.

[0037] The liquid supply unit 212 is coupled to one of the cross beams 228, 230 of the XY gantry assembly 204. The liquid supply unit 212 includes a liquid supply trolley frame that couples a liquid supply member 232 to the XY gantry assembly 204. The liquid supply trolley frame is configured to support the liquid supply member 232 and move and position the liquid supply member 232 along portions of the cross beam 228 that are positioned at points along the +x and -x directions. The liquid supply unit 212 supplies one or more liquids 234 or fluids that are dispensed onto either of the pads 236a, 236b. The liquid supply unit 212 may be connected to one or more fluid sources, such as a liquid supply module 218. The liquid supply member 232 is configured to supply one or both of a polishing liquid, a cleaning liquid, and / or water. The liquid 234 supplied from the liquid supply unit 212 provides liquid at a desired flow rate and pressure. The polishing fluid source can provide one or more fluids, including chemical solutions (e.g., acids, bases, inhibitors, etc.) and / or slurry-containing solutions (e.g., solutions containing abrasive particles (e.g., silica, ceria, or alumina-based abrasives) used in substrate polishing). Water available in the liquid supply unit 212 is a deionized water source. The liquid supply unit 212 can include a pump or multiple pumps (one for each fluid) used to supply liquid at a desired flow rate and pressure to one of the pads 236a, 236b.

[0038] The liquid 234 supplied by the liquid supply unit 212 is dispensed onto one of the first pad 236 a or the second pad 236 b. The liquid 234 is supplied to the first pad 236 a or the second pad 236 b as a spray, whereby the spray is emitted onto the first pad 236 a or the second pad 236 b by the nozzle of the liquid supply member 232. The spray is a continuous stream of liquid, such as a chemical solution, a slurry-containing solution, or water.

[0039] A pad conditioner 214 is coupled to one of the cross beams 228, 230 of the XY gantry assembly 204. In the embodiment of Figure 2A, the pad conditioner 214 is coupled to the cross beam 230, which is located below the cross beam 228. The pad conditioner 214 includes a conditioner trolley frame 246 that couples a conditioning disk 252 to the XY gantry assembly 204. The conditioner trolley frame 246 is configured to support and actuate the conditioning disk 252 such that the conditioning disk 252 translates in the +y and -y directions along the cross beam 230. A vertical actuator 248 is disposed between the conditioning disk 252 and the conditioner trolley frame 246 such that the vertical actuator 248 is configured to move the conditioning disk 252 in the +z and -z directions relative to the conditioner trolley frame 246 and the x-y gantry assembly 204. The vertical actuator 248 may be a hydraulic actuator and may be connected to one or more motion assemblies, such as electrical or pneumatic components 216. Slides or rails within the vertical actuator 248 are used to slidably couple the conditioning disk 252 to the conditioner trolley frame 246. The conditioning disk 252 is used to polish and / or rejuvenate the pads 236 a, 236 b during a pad conditioning process by urging a polishing pad conditioning disk (e.g., a diamond-impregnated disk) against the polishing pad surface, thereby removing a portion of the polishing pad surface. The pad conditioning process can occur between polishing of substrates (i.e., ex-situ conditioning), simultaneously with polishing of substrates (i.e., in-situ conditioning), or both. In some embodiments, the conditioning disk 252 includes a mounting plate for mounting the conditioner disk.

[0040] 2A-2C, neither the carrier head 244 nor the conditioning disk 252 is configured to rotate about a central axis passing through the center of the retaining ring, flexible element, substrate held in the carrier head 244, or pad conditioning disk 252. Instead, the XY gantry assembly 204 is configured to move the carrier head 244 and the conditioning disk 252, respectively, along the top surfaces of the first and second pads 236 a and 236 b in a desired pattern. This configuration significantly simplifies and reduces the cost of the carrier head 244 portion and platen 238 portion of the polishing module 250 compared to conventional CMP polishing hardware designs that require simultaneous and separate rotation and translation of the polishing pads, conditioning disk, and carrier head portions relative to one another. Those skilled in the art will appreciate that the hardware configuration disclosed herein used to perform the polishing process described in detail below provides significant manufacturing and maintenance cost savings and improved reliability due to the elimination or absence of the need for actuators and coupling assemblies that allow the above components to rotate and / or translate while maintaining alignment with the pad surface during processing. Liquid supply unit 212 is configured to supply liquid to first pad 236 a and second pad 236 b, leading or following carrier head 244, during the polishing process.

[0041] As shown in FIGS. 2A-2C, a first platen 238a is disposed on a first side of the polishing space 226 within the system body 202. A basin (not shown) may be disposed around the first platen 238a to catch slurry, water, or other fluids that drip from a pad placed on the first platen 238a. The first platen 238a may be formed of a metallic material and may include multiple sublayers for supporting pads, such as the first pad 236a. As described above, the first platen 238a is a fixed platen and is not configured to rotate or translate, thereby significantly simplifying this area of ​​the polishing module 250 relative to conventional CMP hardware designs. A second platen 238b is disposed on a second side of the polishing space 226 within the system body 202. A container (not shown) may be positioned around the second platen 238b to catch any slurry, water, or other fluid that drips off the pad placed on the second platen 238b. The second platen 238b is similar to the first platen 238a, but is configured to support the second pad 236b and, in some embodiments, to simultaneously process a second substrate on the second pad 236b.

[0042] Auxiliary supports 220, 222 are located on each side of the first platen 238a and the second platen 238b. The auxiliary supports include a first auxiliary support 220 and a second auxiliary support 222. In some embodiments, the auxiliary supports 220, 222 are each configured to support one or more additional arms or devices. In some embodiments, the auxiliary supports 220, 222 are configured to support one or more slurry arms, one or more conditioner arms, or one or more sensors (e.g., cameras, pH sensors, etc.). Each of the auxiliary supports 220, 222 includes one or more rails and actuators positioned at a location along the extension of the platens 238a, 238b in the + / -x direction.

[0043] An electrical and pneumatic component assembly 216 is located on and / or coupled to the exterior wall of the system body 202. In some embodiments, each of the sanding modules 250a, 250b, 250c, and 250d includes electrical and pneumatic components disposed in different regions of the electrical and pneumatic component assembly 216. In some embodiments, each of the sanding modules 250a, 250b, 250c, and 250d shares the electrical and pneumatic component assembly 216. While shown as being attached to the side of the sanding modules 250a, 250b, 250c, and 250d, the electrical and pneumatic component assembly 216 may be coupled to the top or bottom of one of the sanding modules 250a, 250b, 250c, and 250d.

[0044] The electrical and pneumatic component assembly 216 includes components that enable the actuation and / or delivery of fluids during portions of the polishing process performed within the various polishing modules 250 a, 250 b, 250 c, 250 d. In some embodiments, the electrical and pneumatic component assembly 216 includes one or more sub-controllers, one or more power sources, pneumatic reservoirs, vacuum pumps, air pumps, pneumatic valves, pressure regulators, shut-off valves, or one or more gas sources. Each component within the system body 202 can be connected to a sub-controller located within the electrical and pneumatic component assembly 216 to enable distribution and control of the power and / or pressure applied thereto.

[0045] The liquid supply module 218 is similarly located on and / or coupled to the exterior sidewall of the system body 202. In some embodiments, each of the polishing modules 250a, 250b, 250c, and 250d includes a separate liquid supply module 218. In other embodiments, each of the polishing modules 250a, 250b, 250c, and 250d shares one or two liquid supply modules 218. While shown attached to the side of the polishing modules 250a, 250b, 250c, and 250d, the liquid supply module 218 may be coupled to the top or bottom of one of the polishing modules 250a, 250b, 250c, and 250d. The liquid supply module 218 is configured to supply and control the supply of one or more liquids to components within the processing space 226. Thus, the liquid supply module 218 is configured to supply one or a combination of a chemical solution (e.g., an acid, a base, an inhibitor, etc.), a slurry-containing solution (e.g., a solution that may contain abrasive particles (e.g., silica, ceria, or alumina-based abrasives)) used for polishing the substrate, or water (e.g., deionized water).

[0046] Further to the description provided above, each of the polishing modules 250a, 250b, 250c, and 250d includes a central support 208 extending from the bottom surface 202c of the system body 202. The central support 208 is configured to support one or all of the first head cleaning section 266a, the second head cleaning section 266b, and the carrier loading station 268 (FIG. 2C). The central support 208 is disposed between the first platen 238a and the second platen 238b.

[0047] The carrier loading station 268 is located at a distal end of the central support 208 near the inner sidewall 202E of the system body 202. The carrier loading station 268 is configured to receive and hold a substrate once it has been moved into the processing space 226 of the system body 202 and placed in the carrier loading station 268 by the second robot 126. In some embodiments, the carrier loading station 268 is referred to as a load cup. The substrate is then transferred from the carrier loading station 268 to one or more of the first pad 236a or the second pad 236b on the platens 238a, 238b using one or more robots (not shown) or using the carrier head assembly 210.

[0048] The first head cleaning unit 266a and the second head cleaning unit 266b are coupled to the end of the central support 208 opposite the carrier loading station 268. In some embodiments of each module, there is only one head cleaning station. The first head cleaning unit 266a and the second head cleaning unit 266b are configured to allow the carrier head assembly 210 and the pad conditioner 214 to be cleaned between polishing processes performed on substrates. In some embodiments, the positions of the carrier loading station 268 and the head cleaning units 266a, 266b are swapped.

[0049] During the polishing process, the carrier head assembly 210 is actuated in a predetermined pattern 260, causing a substrate disposed within the carrier head assembly 210 to follow a path defined by the actuation pattern. The predetermined pattern 260 can define a lemniscate path, such as a figure-eight path. The predetermined pattern 260 can also define a zigzag or oval path. Other shapes for the predetermined pattern 260 are contemplated. The predetermined pattern 260 is configured to ensure uniform material removal across the surface of the substrate. To form the predetermined pattern 260, the carrier head assembly 210, the pad conditioner 214, and the liquid supply unit 212 are moved along respective cross beams 228, 230 in at least a first direction 276. Each of the cross beams 228, 230 can also be simultaneously moved along the runway beam 224 in a second direction 272. The illustrated predetermined pattern 260 is a path formed by the central axis of the substrate as it is actuated over pads 236a, 236b. In some embodiments, the substrate is placed on one of pads 236a, 236b using a robot different from that used by carrier head assemblies 210. The substrate can be placed at placement location 262 along predetermined pattern 260. In this case, one of carrier head assemblies 210 can be actuated to position the substrate at placement location 262 and secure the substrate beneath carrier head assembly 210. Placement location 262 can be anywhere on pads 236a, 236b. In some embodiments, the substrate is placed at placement location 262, and then one or both of pads 236a, 236b are actuated relative to platen 238 and sidewalls 202c, 202d, 202e, 202f to move the substrate beneath one of carrier head assemblies 210.

[0050] The platens 238a, 238b have a rectangular shape when viewed from above, such that the top surface of each of the platens 238a, 238b on which the pad is placed is rectangular. In some embodiments, the corners of the rectangle may be chamfered or rounded. In some embodiments, the top surfaces of the platens 238a, 238b are oval in shape. In some embodiments, each of the platens 238a, 238b has a first length L1 and a first width W1. The first length L1 is the length of one of the platens 238a, 238b in the X direction. The first width W1 is the width of one of the platens 238a, 238b in the Y direction. In some embodiments, the first length L1 is greater than the first width W1, for example, greater than about 1.5 times, for example, greater than about 2 times, for example, greater than about 2.5 times, or for example, greater than about 3 times. Thus, the aspect ratio of the first length L1 to the first width W1 of either platen 238a, 238b is greater than about 1.5:1, such as greater than about 2:1, such as greater than about 2.5:1, such as greater than about 3:1. The increased first length L1 relative to the first width W1 enhances the ability to form various polishing patterns, such as lemniscate patterns.

[0051] In one embodiment, during a polishing process, carrier head assembly 210 is actuated in a predetermined pattern 260 across a first portion of pad 236a, while pad conditioning disk 252 on conditioner trolley frame 246 is configured to perform a pad conditioning process on a second portion of pad 236a. After polishing of the substrate within the first portion of pad 236a is completed, the conditioned second portion of pad 236a is then aligned with the first portion of pad 236a, allowing another polishing process to be performed on the second portion of pad 236a using carrier head assembly 210 positioned over the second portion. In one example, the first and second portions are equal portions of pad 236a, e.g., each portion covering approximately 50% of the surface area of ​​pad 236a. In one embodiment, the first and second portions are positioned consecutively along the first length L1 of the pad (i.e., the X direction). Alternatively, in other embodiments, in cases where the pads can be aligned or repositioned laterally (i.e., in the Y direction), the first portion and the second portion are arranged consecutively in the direction of the first width W1.

[0052] Each of the polishing modules 250a, 250b, 250c, and 250d has a module height 205, a module width 207, and a module length 274. The module height 205 is the height of one of the polishing modules 250a, 250b, 250c, and 250d in the z-direction, which is perpendicular to the x- and y-directions. The module width 207 is the width of one of the polishing modules 250a, 250b, 250c, and 250d in the y-direction, which is perpendicular to the x- and z-directions. The module length 274 is the length of one of the polishing modules 250a, 250b, 250c, and 250d. The module height 205 is less than about 2000 mm, for example, less than about 1500 mm, for example, less than about 1250 mm, for example, less than about 1000 mm, for example, less than about 750 mm, or for example, less than about 600 mm. The module width 207 is less than about 2500 mm, for example, less than about 2250 mm, for example, less than about 2000 mm, for example, less than about 1800 mm. The module length 274 is from about 1000 mm to about 2500 mm, for example, from about 1000 mm to about 2000 mm, for example, from about 1000 mm to about 1500 mm, for example, from about 1000 mm to about 1250 mm.

[0053] The dimensions of each polishing module 250a, 250b, 250c, and 250d allow each polishing module 250a, 250b, 250c, and 250d to be smaller than conventional chemical mechanical polishing assemblies. The module height 205, module width 207, and module length 274 allow the polishing modules 250a, 250b, 250c, and 250d to be stacked. Not rotating the carrier head assembly 210 or platens 238a, 238b reduces the amount of rotational equipment within the polishing modules 250a, 250b, 250c, and 250d. Because rotational equipment is often bulky, eliminating the rotational equipment allows the dimensions of the polishing modules 250a, 250b, 250c, and 250d to be smaller.

[0054] 3A is a schematic side cross-sectional view of another polishing station 300. The polishing station 300 includes multiple polishing modules 350a, 350b, 350c, and 350d. In some embodiments of the polishing station, there is a first polishing module 350a, a second polishing module 350b, a third polishing module 350c, and a fourth polishing module 350d. Each of the first polishing module 350a, the second polishing module 350b, the third polishing module 350c, and the fourth polishing module 350d is similar and includes similar components for processing substrates. The multiple polishing modules 350a, 350b, 350c, and 350d can be stacked vertically, thereby reducing the footprint of the polishing station 300 and increasing substrate throughput density.

[0055] Each of polishing modules 350a, 350b, 350c, and 350d is similar to polishing modules 250a, 250b, 250c, and 250d of Figures 2A-2C, except that liquid supply unit 212 is replaced with multiple liquid supply arms 302, and one or more pad conditioners 214 are replaced with multiple pad conditioner arms 310. A second cross beam may also be optional and may have a second carrier head assembly 360 (Figure 3C) coupled to it, allowing for simultaneous processing of substrates on one or more pads in each polishing module. Second carrier head assembly 360 may be similar to first carrier head assembly 210 and may also be referred to as a polishing head assembly.

[0056] 3B, one or more liquid supply arms 302 are configured to actuate over each platen 238a, 238b and respective pads 236a, 236b. One or more liquid supply arms 302 are coupled to each of the second auxiliary supports 222 disposed along one side of each platen 238a, 238b. The one or more liquid supply arms 302 may be configured to move along the extension of the second auxiliary support 222 or may be fixed.

[0057] In embodiments in which pad conditioner arm 310 is configured to be positioned along second auxiliary support 222, conditioner arm base 312 includes an actuator, motor, or is coupled to a guide that moves along the extension of second auxiliary support 222. Conditioner arm base 312 is further configured to pivot pad conditioner arm 310 about a conditioner base axis (e.g., a vertical axis), thereby enabling conditioner head 314 to pivot about the conditioner base axis. Pad conditioner arm 310 further includes a conditioner head 314, which includes a mounting plate 316 and a conditioning disk 318. Conditioner head 314 is similar to pad conditioner 214.

[0058] Conditioner head 314 is coupled to conditioner arm base 312 using connecting arm 310. Connecting arm 310 is an arm that supports conditioner head 314 and is rotated by components within conditioner arm base 312. Mounting plate 316 is coupled to the bottom of conditioner head 314 and is configured to support conditioning disk 318 while it is actuated against one of pads 236 a, 236 b on one of platens 238 a, 238 b. Conditioning disk 318 is used to clean and / or rejuvenate pads 236 a, 236 b by cleaning abrasive by-products from pad 236 a, 236 b with a brush (not shown), for example, and / or by abrading pad 236 a, 236 b by pressing an abrasive pad conditioning disk (e.g., a diamond-impregnated disk) against pad 236 a, 236 b. The pad conditioning process can occur between polishing of substrates (ie, ex-situ conditioning), simultaneously with polishing of the substrate (ie, in-situ conditioning), or both.

[0059] One or more liquid feed arms 302 are configured to operate on each platen 238a, 238b and its respective pad 236a, 236b. One or more liquid feed arms 302 are coupled to a respective first auxiliary support 220 disposed along one side of each platen 238a, 238b. The one or more liquid feed arms 302 may be configured to move along the length of the first auxiliary support 220 or may be fixed. In embodiments in which the liquid feed arm 302 is configured to move along the first auxiliary support 220, the feed arm base 304 includes an actuator, motor, or is coupled to a guide that moves along the extension of the first auxiliary support 220. The feed arm base 304 is further configured to rotate the liquid feed arm 302 about a feed base axis (e.g., a vertical axis), thereby allowing the liquid feed arm 302 to rotate about the feed base axis. The feed arm 302 further includes a feed head 306. The delivery head 306 extends over one of the platens 238, 238b and includes at least one nozzle for delivering a liquid, such as liquid 308, to the pads 236a, 236b.

[0060] The liquid supply arm 302 is connected to one or more fluid sources, such as a fluid source coupled to or disposed within the liquid supply module 218. In some embodiments, the liquid supply arm 302 is configured to supply one or both of a polishing liquid (e.g., a slurry-containing liquid) and water. The liquid 308 is supplied from the liquid supply arm 302 to the surface of the polishing pad at a desired flow rate and pressure. The liquid supply arm 302 can provide one or more fluids, including a chemical solution (e.g., an acid, a base, an inhibitor, etc.) and / or a slurry-containing solution (e.g., a solution containing abrasive particles (e.g., silica-, ceria-, or alumina-based abrasives) used in substrate polishing). The water available in the liquid supply arm 302 is a deionized water source. The liquid supply arm 302 can include a pump or multiple pumps (one for each fluid) used to supply the fluid to the surface of the polishing pad.

[0061] The liquid 308 supplied by the liquid supply arm 302 is dispensed onto one of the first pad 236a or the second pad 236b. The liquid 308 is supplied to the first pad 236a or the second pad 236b as a spray, whereby the spray is emitted onto the first pad 236a or the second pad 236b by the nozzle of the supply head 306. The spray can be a continuous stream of liquid, such as a chemical solution, a slurry-containing solution, or water.

[0062] 3C is a schematic, partial cross-sectional top view of the polishing station shown in FIG. 3B. As shown in FIG. 3C, a liquid supply arm 302 and a pad conditioner arm 310 are actuated along the first auxiliary support 220 and the second auxiliary support 222, respectively. In some embodiments, the pad conditioner arm 310 is configured to perform a pad conditioning process before and / or after a substrate is polished on the pad 236a. Thus, the liquid supply arm 302 is actuated along the extension of the first auxiliary support 220 in the direction 352, and the pad conditioner arm 310 is actuated along the extension of the second auxiliary support 222 in the direction 354 (e.g., the +x direction and the −x direction).

[0063] 4A is a schematic side cross-sectional view of another polishing station 400. The polishing station 400 includes multiple polishing modules 450a, 450b, and 450c. In some embodiments, there is a first polishing module 450a, a second polishing module 450b, and a third polishing module 450c. Each of the first polishing module 450a, the second polishing module 450b, and the third polishing module 450c is similar and includes similar components for processing substrates. The multiple polishing modules 450a, 450b, and 450c can be stacked vertically, thereby reducing the footprint of the polishing station 400 and increasing substrate throughput density. One or more support modules 475 can be positioned either below or above the stack of polishing modules 450a, 450b, and 450c. In some embodiments, the support module 475 is positioned to the side of the polishing modules 450a, 450b, 450c, similar to the electrical or pneumatic component assembly 216 or the liquid supply module 218 of Figures 2A-2C.

[0064] 4B, each of the polishing modules 450a, 450b, and 450c includes a system body 202, an XY gantry assembly 204, a carrier head assembly 210, a liquid supply unit 212, one or more pad conditioners 214, a platen 404, a plurality of pads 406a and 406b mounted on the platen 404, and a pad cleaning station 410. Each of the system body 202, the XY gantry assembly 204, the carrier head assembly 210, the liquid supply unit 212, and the one or more pad conditioners 214 are similar to those described in FIGS. 2A-2C. However, in one configuration, the platen 404 is a two-sided platen configured to support a first pad 408a on a first side and a second pad 408b on a second side. The pad cleaning station 410 is located on an opposite side of the platen 404 from the XY gantry assembly 204, the carrier head assembly 210, and the liquid supply unit 212. The liquid supply unit 212 may also be mechanically coupled to the carrier head assembly 210 using a liquid supply arm 466. The liquid supply arm 466 may enable the liquid supply unit 212 to be maintained at a constant distance and position from the carrier head assembly 210 while the carrier head assembly 210 is moving. The liquid supply arm 466 may enable the liquid supply unit 212 to be detached from the XY gantry assembly 204, which may reduce the complexity of the XY gantry assembly 204.

[0065] The platen 404 has a pad conveyor system 408 disposed thereon. The platen 404 and pad conveyor system 408 are part of a multi-pad platen assembly 405. The multi-pad platen assembly 405 can be similar to the multi-pad platen assembly 900 of FIGS. 9A and 9B, such that the multi-pad platen assembly 900 is interchangeable with the multi-pad platen assembly 405. The pad conveyor system 408 includes a flexible belt having a first pad docking area 408a and a second pad docking area 408b. The belt can be configured as a conveyor and is configured to move the first pad 406a and the second pad 406b between a processing position and a cleaning position. The belt can be similar to the belt 908 of FIGS. 9A and 9B. While positioned in the processing position, the first pad 406 a or the second pad 406 b is positioned facing the carrier head assembly 210 and the XY gantry assembly 204 and is configured to function as a polishing pad or buffing pad. While positioned in the cleaning position, the first pad 406 a or the second pad 406 b is positioned facing the pad cleaning station 410 and is configured to be rinsed or cleaned simultaneously with processing of a substrate on a pad positioned in the processing position on the opposite side of the platen 404. The pad conveyor system 408 may further include first and second rollers similar to the first and second rollers 904 a and 904 b in FIG. 9B . The first and second rollers are spaced apart from each other and positioned at opposite ends of the platen 404 and the pad conveyor system 408, respectively, aligned along the ±X directions. 9A and 9B. The size of the first and second rollers and belts that form the pad conveyor system 408 controls the radius of curvature that the pads 406a, 406b are configured to withstand. One or more belt drives 402 are coupled to the pad conveyor system 408 and configured to operate the pad conveyor system 408 during process operations.In some embodiments, the platen 404 is formed from a metallic material and may include one or more sublayers (e.g., coatings or removable plates) to support the pads 406a, 406b to further minimize wear and allow movement of the belt relative to the platen.

[0066] Rotating the first and second rollers indexes the pads 406a, 406b between the processing and cleaning positions. Because a belt is disposed around and in contact with the first and second rollers, rotating the first and second rollers in turn indexes the belt. The pads 406a, 406b are coupled to the belt and therefore move with the belt from one side of the platen 404 to the opposite side of the platen 404. The belt can also contact the platen 404 on both sides of the platen 404 such that the belt is under tension and contacts not only the platen 404 but also the first and second rollers. Using the pad conveyor system 408 to move the pads 406a, 406b from one side to the other allows one of the pads 406a, 406b to be used for substrate processing while the other pad 406a, 406b is being cleaned. The pad conveyor system 408 is also compact, allowing for small polishing modules 450 a, 450 b, 450 c. The location of the platen 404 within the pad conveyor system 408 allows for efficient alignment of the pads 406 a, 406 b and allows for pressure to be applied to the pads 406 a, 406 b during processing.

[0067] The pad cleaning station 410 includes two cleaning runway beams 410 coupled to the inner sidewalls 202C and 202D of the system body 202. The pad cleaning station 410 further includes a cleaning cross beam 414 disposed between the two cleaning runway beams 410. The cleaning cross beam 414 includes multiple nozzles 420 oriented toward the bottom side of the platen 404. The multiple nozzles 420 are configured to dispense cleaning liquid 416, such as water, onto a pad, such as the second pad 406b, disposed on the bottom side of the platen 404 when the platen 404 is positioned in the cleaning position. Each nozzle 420 is connected to a fluid source, such as a fluid source connected to or disposed within a liquid supply module. The cleaning cross beam 414 is similar to one of the cross beams 228, 230 of the XY gantry assembly 204 in that it is configured to operate along the extension of the cleaning runway beam 410.

[0068] Returning to Figure 4A, support module 475 includes one or more liquid supply modules 456, 458, 460 and one or more electrical or pneumatic components 462, 464. Liquid supply modules 456, 458, 460 are similar to liquid supply module 218 of Figures 2A-2C and 3A-3C. One or more electrical or pneumatic components 462, 464 are similar to electrical or pneumatic component assembly 216 of Figures 2A-2C and 3A-3C.

[0069] 4C is a schematic, partial cross-sectional top view of the polishing station 400 of FIG. 4B. Each polishing module 450a, 450b, 450c further includes a carrier loading station 268 at the distal end of the platen 404. As described with respect to FIGS. 2A-2C, the carrier head assembly 210 is actuated over the first pad 406a and / or the second pad 406b along a predetermined pattern 260.

[0070] The platen 404 has a rectangular shape when viewed from above, such that the top surface of the platen 404 on which the pad rests is rectangular. In some embodiments, the corners of the rectangle may be chamfered or rounded. The rectangular shaped platen is configured to accommodate a polishing pad having a non-axisymmetric polishing surface, such as a non-circular or out-of-round polishing pad. In one example, the non-axisymmetric polishing pad has a rectangular shape that fits flush with or circumscribes the edge of the platen 404. In some embodiments, the top surface of the platen 404 is oval in shape. In some embodiments, the platen 404 has a second length L2 and a second width W2. The second length L2 is the length of the platen 404 in the X direction. The second width W2 is the width of the platen 404 in the Y direction. The second length L2 is greater than the second width W2, e.g., greater than about 1.5 times, e.g., greater than about 2 times, e.g., greater than about 2.5 times, e.g., greater than about 3 times. Accordingly, the aspect ratio of the second length L2 to the second width W2 of the platen 404 is greater than about 1.5:1, e.g., greater than about 2:1, e.g., greater than about 2.5:1, e.g., greater than about 3:1. The increased second length L2 relative to the second width W2 enhances the ability to form various polishing patterns, such as lemniscate patterns. In some embodiments, the pad conditioner 214 is configured to perform a pad conditioning process before and / or after a substrate is polished on the pad 236a.

[0071] Each of the polishing modules 450a, 450b, and 450c has a module height 452, a module width 454, and a module length 474. The module height 452 is the height of one of the polishing modules 450a, 450b, and 450c in the z-direction, which is perpendicular to the x- and y-directions. The module width 454 is the width of one of the polishing modules 450a, 450b, and 450c in the y-direction, which is perpendicular to the x- and z-directions. The module length 474 is the length of one of the polishing modules 450a, 450b, and 450c. The module height 452 is less than about 2000 mm, such as less than about 1500 mm, such as less than about 1250 mm, or less than about 1000 mm. The module width 454 is less than about 3000 mm, such as less than about 2500 mm. The module length 474 is about 1000 mm to about 2500 mm, for example, about 1000 mm to about 2000 mm, for example, about 1100 mm to about 1500 mm, for example, about 1150 mm to about 1250 mm.

[0072] The dimensions of each polishing module 450a, 450b, 450c allow each polishing module 450a, 450b, 450c to be smaller than conventional chemical mechanical polishing assemblies. The module height 452, module width 454, and module length 474 allow the polishing modules 450a, 450b, 450c to be stacked. Not using a rotating carrier head assembly 210 or platen 404 reduces the amount of rotating equipment in the polishing modules 450a, 450b, 450c, because rotating equipment adds complexity to the system and often needs to be replaced. Therefore, not utilizing a rotating carrier head assembly 210 allows for smaller polishing module 450a, 450b, 450c dimensions. In this configuration, polishing modules 450a, 450b, 450c are significantly simplified, easier to maintain, and much less expensive than conventional CMP polishing hardware designs that require separate rotation and translation of the polishing pad and carrier head portions relative to each other simultaneously.

[0073] Figure 5 is a schematic, partial cross-sectional top view of the polishing station 600 or polishing station 700 shown in Figures 6 and 7. The polishing station 600, 700 can be used in place of one of the polishing stations 200, 300, 400 of Figures 2A-4C. In some embodiments, the polishing station 600, 700 can be incorporated into the polishing station 200, 300, 400 of Figures 2A-4C, such that the polishing station 600, 700 is one or more of the polishing modules 250a, 250b, 250c, 250d, 350a, 350b, 350c, 350d, 450a, 450b, 450c, and is stacked. Both the polishing station 600 and the polishing station 700 include a head actuation assembly 505, multiple liquid supply modules 518, a carrier loading station 268, a first head cleaning section 266a, a second head cleaning section 266b, and multiple platens. In the polishing station 600 of Figure 6, the platens are fixed platens 638a, 638b. In the polishing station 700 of Figure 7, the platens are multi-pad support platens 738a, 738b.

[0074] FIG. 6 is a schematic cross-sectional side view of a polishing station 600. As shown in the embodiment of FIG. 6, each head assembly 504a, 504b is coupled to a central rail support 502 using two rails 610. The rails 610 extend along the length of the central rail support 502. The rotation axes 606, 608 of the rotation shafts 510 are also shown, with the first head assembly 504a having the first rotation axis 606 and the first head assembly 504a moving about the rotation axis 606. In some embodiments, the first head assembly 504a and the second head assembly 504b can be actuated using a rotation motor (not shown) configured to position the first head assembly 504a and the second head assembly 504b about their respective rotation axes 606, 608 and to cause angular movement of the first head assembly 504a and the second head assembly 504b. The second head assembly 504b has a second rotation shaft 510 that includes a second rotation axis 608, and the second head assembly 504b moves about the rotation axis 608. The platens 638a, 638b of the polishing station 600 are not configured to move and are fixedly positioned, thereby utilizing the pads 236a, 236b in the same manner as those in Figures 2A-2C.

[0075] 7 is a schematic cross-sectional side view of a polishing station 700. The polishing station 700 includes multiple pad support platens 738a, 738b, such that the polishing station 700 includes a first platen 738a configured to support a pad on both sides and a second platen 738b configured to support a pad on both sides. The polishing station 700 also includes one or more pad cleaning stations 702a, 702b.

[0076] Returning to FIG. 5 , both the polishing station 600 and the polishing station 700 can further include a liquid supply arm and a conditioner arm disposed on the head actuation assembly 505, with the liquid supply arm and the conditioner arm coupled to separate guide rails disposed along the center rail support 502. The center rail support 502 extends along the extension of the upper inner sidewall 202A. The center rail support 502 includes a metal beam configured to support one or more head assemblies 504 a, 504 b. In some embodiments, a first head assembly 505 is coupled to a first side of the beam, and a second head assembly 505 is coupled to a second side of the beam. The center rail support 502 includes grooves along which the head assemblies 504 a, 504 b can operate, and can further include power lines and fluid supply lines (not shown) disposed through the center rail support. The liquid supply arm and conditioner arm are similar to liquid supply arm 302 and pad conditioner arm 310 of Figures 3A-3C. Pad conditioner arm 310 may also be similar to pad conditioner arm 720 of Figure 7.

[0077] The head actuation assembly 505 includes a first head assembly 504a and a second head assembly 504b. The first head assembly 504a and the second head assembly 504b are similar and are disposed on opposite sides of a center rail support 502. The center rail support 502 is coupled to the upper inner sidewall 202A of the system body 202 and is disposed along the extension of the platens within the processing space 226. The first head assembly 504a extends over a first platen, such as first platen 638a or first platen 738a. The second head assembly 504b extends over a second platen, such as second platen 638b or second platen 738b.

[0078] Each of the head assemblies 504a, 504b is configured to actuate a carrier head assembly 210 coupled to its distal end. The head assemblies 504a, 504b further include a linear actuator 508 connected to the center rail support 502 and a support arm 512 connecting the carrier head assembly 210 to the linear actuator 508. The linear actuator may include a linear motor, a lead screw, a ball screw, a rack and pinion, a chain drive, a belt drive, or other similar device configured to reciprocate a part in a linear direction. The support arm 512 is coupled to a rotating shaft 510 disposed through an inner distal end of the support arm 512. The rotating shaft 510 may further include a motor or pneumatic assembly disposed on or through a portion of the linear actuator 508 and connected thereto, thereby enabling the support arm 512 and carrier head assembly 210 to oscillate about the rotating shaft 510 and thus translate in the x-y plane. A head support shaft 514 is disposed through the distal end of the support arm 512 opposite the rotation shaft 510. The head support shaft 514 supports and couples the carrier head assembly 210 to the support arm 512.

[0079] Both carrier head assemblies 504a, 504b can be coupled together or can be separately controlled using commands communicated from the system controller 170. In some embodiments, the head assemblies 504a, 504b are separately controlled such that the head assemblies 504a, 504b are actuated along the length 506 of the center rail support 502 and separately rotated about a rotational shaft 510 using a rotary actuator (e.g., a stepper motor). In some embodiments, as shown in FIGS. 6-8B , the head assemblies 504a, 504b are actuated using a linear actuator, which may include a linear motor, a lead screw, a ball screw, a rack and pinion, a chain drive, a belt drive, or other similar device configured to reciprocate a part in a linear direction along the center rail support 502. Each head assembly 504a, 504b is coupled to one or more rails 610 on either side of the center rail support 502 ( FIG. 6 ). One or more rails 610 allow the head assemblies 504a, 504b to move along the extension of the center rail support 502. Moving the head assemblies 504a, 504b along the extension of the center rail support 502 enables a wide range of polishing patterns, thereby moving the head assemblies 504a, 504b in a path that promotes uniform polishing of the substrate. This movement also allows the polishing stations 600, 700 to perform polishing processes without the need to rotate the carrier head assembly. The use of a non-rotating carrier head assembly reduces system complexity, the likelihood of mechanical failure, and the overall system size. Thus, in some embodiments, a linear actuator is the only means of generating relative motion between the carrier head and a non-axisymmetric polishing pad mounted on a rectangular pad support surface.

[0080] Each of the liquid supply modules 518 is disposed on a portion of one of the platens 638a, 638b or 738a, 738b. The liquid supply modules 518 are similar to the liquid supply module 218 of Figures 2A-2C. The liquid supply modules 518 are coupled to the inner side of the system body 202 and may also be coupled to the inner top surface of the system body 202. Alternatively, the liquid supply module 518 may be located outside the system body 202, and one or more polishing stations 600, 700 may share the same liquid supply module 518.

[0081] The carrier loading station 268, the first head cleaning unit 266a, and the second head cleaning unit 266b are each disposed between the platens 638a and 638b or between the platens 738a and 738b, similar to the embodiment in Figures 2A to 2C. As shown in Figure 6, the carrier loading station 268, the first head cleaning unit 266a, and the second head cleaning unit 266b are supported by a central support 620 similar to the central support 208 in Figures 2A to 2C.

[0082] The platens 638a, 638b of the polishing station 600 are fixed and therefore not configured to move relative to the walls of the processing module during or between process operations. However, the pads coupled to each of the platens 738a, 738b of the polishing station 700 are configured to be moved between process operations so that the pads disposed on the upper surfaces of the platens 738a, 738b facing the head assemblies 504a, 504b can be replaced with different pads that have been cleaned and / or conditioned. Each of the platens 638a, 638b and 738a, 738b is coupled to a platen support 516. In some embodiments, the platen support 516 is coupled to the sides of each of the platens 638a, 638b and 738a, 738b and to the first inner sidewall 202c of the system body 202. Platen support 516 provides mechanical support for each of platens 638a, 638b and 738a, 738b. Platen support 516 and one of platens 638a, 638b together form platen assembly 650. Platen support 516 and one of platens 738a, 738b together form multi-pad platen assembly 750. Platen support 516 may be a cantilevered support such that only one side of platen support 516 is mechanically coupled to system body 202, and the end of platen support 516 to which platens 638a, 638b, 738a, 738b are coupled is free-hanging. Alternatively, a platen support 516 is disposed on each side of each of the platens 638a, 638b, 738a, 738b to support both sides of the platens 638a, 638b, 738a, 738b. In embodiments where there are two platen supports 516 per platen 638a, 638b, 738a, 738b, the platen assemblies 650, 750 are coupled to both the first inner sidewall 202c and the sides of the central support 620.

[0083] In the polishing station 700 of FIG. 7, the platen support 516 may further include a belt drive similar to the belt drive 402 of FIGS. 4A-4C. In embodiments in which the platen support 516 includes the belt drive 402, the platen support 516 further includes a first roller 510a and a second roller 520b spaced apart from one another and disposed at opposite ends of the platens 738a, 738b, respectively. The first roller 510a and the second roller 520b form part of a conveyor system that includes a belt 770 disposed around each of the platens 738a, 738b and configured to be rotated by the first roller 510a and the second roller 520b. Each platen support 516, one of the platens 738a, 738b, the rollers 510a, 510b, and the belt 770 collectively form a multi-pad platen assembly 750. Within the processing space 226 of the polishing station 700 are two multi-pad platen assemblies 750. The multi-pad platen assemblies 750 allow for the alignment of two or more pads around a single platen 738a, 738b. A belt 770 moves in a rotational direction 764 parallel to the length direction 506.

[0084] Each belt 770 is disposed around the first roller 510a, the second roller 520b, and one of the platens 738a, 738b. One or more pads are coupled to each belt 770. The pads are aligned between a processing position and a cleaning position by rotating the first roller 510a and the second roller 510b, respectively. The processing position and the cleaning position are similar to the processing position shown in FIGS. 4A-4C. Because the belt 770 is disposed around and in contact with the first roller 510a and the second roller 510b, rotating the first roller 510a and the second roller 510b subsequently aligns the belt 770. The pads are coupled to the belt 770 and therefore move with it from one side of the platens 738a, 738b to the opposite side of the platens 738a, 738b. The belt 770 can also contact both sides of the platens 738a, 738b, such that the belt 770 is under tension and in contact with both the first roller 510a and the second roller 510b as well as one of the platens 738a, 738b. Using the belt 770 and rollers 510a, 510b to move the pads from one side to the other allows one pad on the belt 770 to be used for substrate processing while the other pad is being cleaned. The pad conveyor system is also compact, allowing for the miniaturization of the polishing modules 450a, 450b, 450c. The location of the platen 404 within the pad conveyor system 408 allows for efficient alignment of the pads 406a, 406b and allows for pressure to be applied to the pads 406a, 406b during processing.

[0085] The polishing station 600 has a station height 604, a station width 602 (FIG. 6), and a station length 530. The station height 604 is the height of the polishing station 600 in the z-direction, which is perpendicular to the x- and y-directions. The station width 602 is the width of one of the polishing stations 600 in the y-direction, which is perpendicular to the x- and z-directions. The station length 530 is the length of one of the polishing stations 600. The station height 604 is less than about 2000 mm, for example, less than about 1500 mm, for example, less than about 1250 mm, for example, less than about 1050 mm, for example, less than about 1000 mm. The station width 602 is less than about 3500 mm, for example, less than about 3000 mm, for example, less than about 2750 mm, for example, less than about 2500 mm. The schedule length 530 is about 1000 mm to about 2500 mm, for example, about 1000 mm to about 2000 mm, for example, about 1000 mm to about 1500 mm, for example, about 1100 mm to about 1250 mm.

[0086] Each of the platens 638a, 638b, 738a, and 738b has a rectangular shape when viewed from above, such that the top surface of each of the platens 638a, 638b, 738a, and 738b on which the pad rests is rectangular. In some embodiments, the corners of the rectangle may be chamfered or rounded. In some embodiments, the top surfaces of the platens 638a, 638b, 738a, and 738b are oval in shape. In some embodiments, each of the platens 638a, 638b, 738a, and 738b has a first length L1 and a first width W1, as depicted in FIGS. 2A-3C, and has similar advantages as depicted in FIGS. 2A-3C.

[0087] The dimensions of each polishing station 600 are smaller than those of conventional chemical mechanical polishing assemblies. The station height 604, station width 602, and station length 530 further enable stacking of the polishing stations 600. Not rotating the carrier head assembly 210 or platens 638a, 638b reduces the amount of rotational equipment within the polishing module 600d. Because rotational equipment is often bulky, eliminating the rotational equipment allows for smaller dimensions of the polishing module 600d. In this configuration, the polishing module 600d is significantly simplified, easier to maintain, and much less costly than conventional CMP polishing hardware designs that require separate rotation and translation of the polishing pad and carrier head portions relative to each other. The polishing station 600 of FIG. 6 further reduces mechanical complexity compared to the embodiments of FIGS. 2A-4C. Providing a single pivot point for each head assembly 504 a, 504 b on the rotating shaft 510 and a set of rails 610 along which the head assemblies 504 a, 504 b move allows a range of motion similar to that of the XY gantry assembly 204 without having any moving parts directly over the polishing pad, which can generate particles and increase their exposure to process chemistries. Not having moving parts directly over the polishing pad reduces the amount of contaminants that can fall onto the polishing pad while still allowing a range of motion for each head assembly 504 a, 504 b.

[0088] 7, a first platen 738a has a first pad 236a on a first side and a second pad 708a on a second side of the first platen 738a opposite the first side. The second pad 708a is either a polishing pad or a buffing pad. A second platen 738b has a first pad 236b on a first side and a second pad 708b on a second side of the second platen 738b opposite the first side. The second pad 708b is either a polishing pad or a buffing pad. In some embodiments, the first pad 236b and the second pad 708b mounted on the second platen 738b are referred to as the third pad and the fourth pad, respectively, to distinguish them from the first pad 236a and the second pad 708a on the first platen 738a. A first belt 770 is configured to align the first pad 236 a with the second pad 708 a to periodically alternate positions of the pad 236 a with the pad 708 a. A second belt 770 is disposed around the periphery of the platen 738 b and is configured to align the first pad 236 b with the second pad 708 b to periodically alternate positions of the first pad 236 b with the second pad 708 b. The first pad 236 a and the second pad 708 a are aligned between process operations so that the first pad 236 a and the second pad 708 a are held in position during process operations.

[0089] In some embodiments, the first platen 738a and the second platen 738b each carry either a polishing pad or a buffing pad, allowing multiple processes to be performed on substrates within the same polishing station 700. In other embodiments, the first platen 738a and the second platen 738b each carry two different polishing pads, both configured to polish substrates but having different chemical or mechanical properties (e.g., polishing surface hardness, different groove patterns, material compositions, etc.). In the polishing station 700, one of the first pad 236a or the second pad 708a is used to process a substrate, while the other of the first pad 236a or the second pad 708a is rinsed and / or cleaned. Substrate processing includes polishing or buffing the substrate. Similarly, one of the first pad 236b or the second pad 708b of the second platen 738b is used to process a substrate, while the other of the first pad 236b or the second pad 708b is rinsed and / or cleaned.

[0090] In the configuration of FIG. 7, the polishing module 700 is significantly simplified, easier to maintain, and much less expensive than conventional CMP polishing hardware designs that require separate and simultaneous rotation and translation of the polishing pad and carrier head portions relative to one another. The polishing station 700 of FIG. 7 further reduces mechanical complexity compared to the embodiment of FIGS. 4A-4C. By providing a single pivot point for each head assembly 504a, 504b on the rotating shaft 510 and a set of rails 610 along which the head assemblies 504a, 504b move, a range of motion similar to that of the XY gantry assembly 204 is possible without placing any moving parts directly above the polishing pad, which can generate particles and increase exposure to process chemistries. Having no moving parts directly above the polishing pad reduces the amount of contaminants that can fall onto the polishing pad while still allowing a range of motion for each head assembly 504a, 504b. 6 in that it allows multiple pads to be placed on the platens 738a, 738b and the pads to be aligned. The use of multiple pads on a single platen 738a, 738b allows one of the pads to be used for polishing while the other is being cleaned simultaneously. Thus, downtime of the polishing station 700 due to pad cleaning is significantly reduced.

[0091] Washing and / or cleaning of the pads 236a, 236b, 708a, 708b is performed using pad cleaning stations 702a, 702b. Both pad cleaning stations 702a, 702b include two cleaning runway beams 707 coupled to a sidewall, e.g., bottom inner sidewall 202B, of the system body 202. Each pad cleaning station 702a, 702b further includes a cleaning cross beam 704 disposed between the two cleaning runway beams 707. The cleaning cross beam 704 includes multiple nozzles 705 oriented toward the bottom sides of the platens 738a, 738b. The multiple nozzles 705 are configured to dispense a cleaning liquid 706, such as water, onto a pad, e.g., the second pad 708a, 708b, disposed on the bottom side of the platens 738a, 738b. Each nozzle 705 is connected to a fluid source, such as a liquid supply unit. The cleaning cross beam 704 is similar to one of the cross beams 228, 230 of the XY gantry assembly 204 in that it is configured to operate below the bottom surface of each of the platens 738a, 738b and along the extension of the cleaning runway beam 707.

[0092] Each pad cleaning station 702a, 702b further includes a conditioner arm 710. Each conditioner arm 710 further includes a pad conditioner 720, a connecting arm 712, a conditioner rotation shaft 714, a linear conditioner actuator 716, and one or more conditioner rails 718 disposed on the sides of central support 620. Pad conditioner 720 is similar to either pad conditioner 214 or conditioner head 314.

[0093] At least one conditioner arm 710 is configured for use with each pad cleaning station 702 a, 702 b. The conditioner arm 710 moves along the extension of the central support 620 to reach the full length of the polishing pad and is configured to swing about a conditioner axis of rotation 719 disposed through each of the conditioner rotation shafts 714. The combination of swinging about the conditioner axis of rotation 719 and linear motion along the conditioner rail 718 allows the pad conditioner 720 to reach all desired areas of a pad coupled to one of the platens 738 a, 738 b.

[0094] Connecting arm 712 is coupled to conditioner rotating shaft 714 such that conditioner rotating shaft 714 is disposed through an inner distal end of connecting arm 712. Conditioner rotating shaft 714 is further disposed through a portion of linear conditioner actuator 716 and may include a motor or pneumatic assembly coupled thereto, which enables connecting arm 712 and pad conditioner 720 to oscillate about conditioner axis of rotation 719. Pad conditioner 720 is coupled to the distal end of connecting arm 712 opposite conditioner rotating shaft 714.

[0095] FIG. 8A is a schematic cross-sectional side view of a polishing station 800. The polishing station 800 is similar to the polishing station 700 of FIG. 7, except that the head actuation assembly 505 is replaced with a head actuation assembly 804. The polishing station 800 can be used in place of any of the polishing stations 200, 300, and 400 of FIGS. 2A-4C. In some embodiments, the polishing station 800 can be incorporated into the polishing stations 200, 300, and 400 of FIGS. 2A-4C, such that the polishing station 800 is one or more of the polishing modules 250a, 250b, 250c, 250d, 350a, 350b, 350c, 350d, 450a, 450b, and 450c, and is stacked. The head actuation assembly 804 includes both the first head assembly 504a and the second head assembly 504b. The first head assembly 504a and the second head assembly 504b are individually coupled to arm supports 814a, 814b, respectively. The arm supports 814a, 814b may be a single arm support extending outward from the central rotating shaft 812, or may be multiple arm supports 814a, 814b extending outward from the central rotating shaft 812. In some embodiments, there is a different arm support 814a, 814b for each of the head assemblies 504a, 504b. The first head assembly 504a is supported by the first arm support 814a, and the second head assembly 504b is supported by the second arm support 814b.

[0096] Polishing station 800 may further include a liquid supply arm and a conditioner arm disposed on head actuation assembly 804, with the liquid supply arm and conditioner arm coupled to separate guide rails along center rail support 806. The liquid supply arm and conditioner arm may be similar to liquid supply arm 302 and pad conditioner arm 310 of Figures 3A-3C. Pad conditioner arm 310 may also be similar to pad conditioner arm 720 of Figure 7.

[0097] The central rotation shaft 812 is disposed between the first head assembly 504a and the second head assembly 504b. The central rotation shaft 812 is configured to allow the first head assembly 504a and the second head assembly 504b to rotate about a central axis 820. By rotating the first head assembly 504a and the second head assembly 504b about the central axis 820, the positions of the first head assembly 504a and the second head assembly 504b can be switched so that the first head assembly 504a is positioned above the second platen 738b and the second head assembly 504b is positioned above the first platen 738a. Therefore, a substrate held by either of the head assemblies 504a or 504b can be efficiently moved to any one of the multiple pads of the polishing station 800, such as the pads 236a, 236b, 708a, and 708b. Arm supports 814a, 814b may also be utilized to support one or more liquid supply units, liquid supply arms, or conditioner arms.

[0098] The central rotating shaft 812 is mechanically coupled to and extends downward from the linear actuator 810. The linear actuator 810 is similar to the linear actuator 508 or the linear conditioner actuator 716. The linear actuator 810 is configured to move along one or more rails 808 coupled to a central rail support 806. The central rail support 806 is coupled to or is part of the upper inner sidewall 202A of the system body 202. The rails 808 rest on the bottom surface of the central rail support 806. The rails 808 and central rail support 806 extend along the length of the polishing station 800 so that the head assemblies 504a, 504b can operate over the desired area from each pad 236a, 236b, 708a, 708b.

[0099] FIG. 8B is a schematic, partial cross-sectional top view of the polishing station 800 of FIG. 8A. Rails 808 are shown extending from one side of the system body 202 to the opposite side. A linear actuator 810 is configured to move in a longitudinal direction 852. The polishing station 800 of FIGS. 8A and 8B has similar advantages to the polishing station 700 of FIG. 7, but further reduces the number of rails, using only one set of rails 808. This is made possible by utilizing a rotating central rotary shaft 812. The central rotary shaft 812 also allows for simultaneous movement of both head assemblies 504a, 504b and reduces mechanical complexity, improving maintenance of the polishing station 800.

[0100] 9A and 9B are schematic diagrams of a multi-pad platen assembly 900. The multi-pad platen assembly 900 can be used in place of either the multi-pad platen assembly 405 or the multi-pad platen assembly 750 of FIGS. 4A-4C, 7, and 8. The multi-pad platen assembly 900 is an exemplary embodiment including multiple pads that can be aligned within a polishing station or polishing module. The multi-pad platen assembly 900 includes a platen 905, a first roller 904a disposed on a first side of the platen 905, a second roller 904b disposed on a second side of the platen 905, platen supports 920 disposed on both sides of the platen 905, a belt 906 disposed around the platen 905 and the rollers 904a and 904b, and a pad stop 926.

[0101] The platen 905 is formed of a metallic material and may include one or more sublayers (e.g., coatings or removable plates) to support the pads 902a, 902b to further minimize wear and allow movement of the belt 906 relative to the platen 905. Grooves for positioning the rollers 904a, 904b may be disposed at either end of the platen 905. The grooves are configured to reduce the clearance through which the belt 906 moves as it extends between the platen 905 and the rollers 904a, 904b. As shown in FIG. 9A , a first end 916 of the first roller 904a is disposed within an opening in a first platen support 920, and a second end 918 of the second roller 904b is disposed within an opening in a second platen support 920. Bearings 922 are disposed between the first roller 904a and each platen support 920 to allow rotation of the first roller 904a. To cause rotation of the first roller 904a, a motor 924 may be connected to either the first end 916 or the second end 918 of the first roller 904a and is disposed within the first platen support 920. In some embodiments, the motor 924 is disposed within both the first platen support 920 and the second platen support 920 and is connected to both the first end 916 and the second end 918, reducing the strain on the single motor 924. The second roller 904b is disposed within the platen support 920 in a manner similar to the first roller 904a.

[0102] One or more pad stops 916 are positioned around the contour on which the pad is configured to be positioned. The one or more pad stops 916 may be one pad stop 916 configured to surround the entire polishing pad, or may be multiple separate pad stops 916 positioned at various locations around the circumference of the polishing pad, such as polishing pads 902a, 902b. The pad stops 916 may be slight protrusions extending outward from the belt 906 or may be grooves in the belt 906.

[0103] 9B , the belt 906 is wrapped around the polishing platen 905 so that the belt 906 contacts a first surface 908 and a second surface 910 opposite the first surface 908. The belt 906 includes a first pad support surface 912 and a second pad support surface 914. The first pad support surface 912 is a position on which the first pad 902a is placed. The second pad support surface 914 is a position on which the second pad 902b is placed. The first pad support surface 912 and the second pad support surface 914 are configured to operate over the first roller 904a and the second roller 904b, respectively, when the pads 902a, 902b are aligned from one side of the platens 908, 910 to the opposite side of the platens 908, 910.

[0104] 10 is a flow diagram illustrating a method 1000 utilizing one or more polishing pads during a substrate polishing sequence. The polishing pad used in method 1000 can be any one of pads 236a, 236b, 406a, 406b, 708a, and 708b of the embodiments described herein. During method 1000, a substrate is polished on a first polishing pad, while the first polishing pad is held in a first position during step 1002. The first position is a fixed position, whereby the first polishing pad does not move. The first position is an upward-facing position, whereby the first polishing pad is positioned facing one or more carrier head assemblies, such as carrier head assembly 210.

[0105] While in the first position, the substrate is urged against the first polishing pad and moved in a predetermined pattern to polish the substrate. In some embodiments, step 1002 is a buffing process instead of a polishing process, whereby the polishing pad is a buffing pad and the applied fluid enables the buffing process. In other embodiments, step 1002 is a polishing process instead of a buffing process, whereby the first polishing pad is a polishing pad. During processing, the substrate is moved over the first pad in a predetermined pattern at a predetermined speed to obtain a desired polishing profile. While the substrate is moved over the first polishing pad, the substrate can be moved in a lemniscate-like path to ensure uniform material removal across the surface of the substrate. During step 1002, a slurry or other polishing fluid can be dispensed onto the polishing pad. In some embodiments, a conditioning disk can also be used during step 1002 to condition the polishing pad while processing the substrate.

[0106] After using the first polishing pad to polish a substrate in step 1002, the polishing pad is aligned from the first position to the second position during step 1004. The second position is on the opposite side of the platen, such as one of the platens 404, 738a, or 738b. The second position faces one or more pad cleaning stations, such as one of the pad cleaning stations 410, 702a, or 702b. Aligning the first polishing pad includes moving the polishing pad using one or more belts, such as one of the belts 770, 906 or the belts of FIGS. 4A-4C. In some embodiments, the first polishing pad is coupled to a belt wrapped around the platen. One or more rollers can be configured to move the belt and the polishing pad.

[0107] Once the first polishing pad is in the second position, the second polishing pad is placed in the first position because the second polishing pad is on the opposite side of the belt. The second polishing pad can be any one of pads 236b, 406a, 406b, 708a, or 708b. In some embodiments, the second polishing pad is used to buff the substrate during step 1006 and therefore can be a buffing pad. In other embodiments, step 1006 is a polishing process instead of a buffing process, whereby the second polishing pad is a standard polishing pad. Similar to step 1002, the substrate is moved over the second polishing pad in a predetermined pattern at a predetermined speed to obtain a desired substrate profile. While the substrate is moved over the second polishing pad, the substrate can be moved in a lemniscate-like path. One or more fluids can optionally be dispensed onto the buffing pad during step 1006.

[0108] Once the first polishing pad is in the second position, the first polishing pad is cleaned during step 1008. Step 1008 includes spraying a cleaning liquid, such as water, onto the polishing pad. During step 1008, a conditioning disk, such as one or more of pad conditioners 214 or 720, is also utilized to condition the first polishing pad. The pad cleaning station further includes one or more additional brushes for removing slurry and contaminants from the first polishing pad. The upside-down orientation of the first polishing pad further aids in the removal of slurry and other contaminants, which will loosen and fall off the first polishing pad.

[0109] After cleaning the first polishing pad, method 1000 is repeated. When repeating method 1000, a new substrate or the same substrate can be used. In embodiments where the same substrate is being processed, the head holding the substrate can hold the substrate during alignment of the polishing pad and place the substrate back onto the polishing pad without releasing it or grabbing a new substrate. In some embodiments, there is one or more intermediate steps in which a second polishing pad and / or buffing pad is cleaned in the same manner as the first polishing pad.

[0110] Advantages of the present disclosure include the ability to create a more modular and compact polishing station. In some embodiments, the polishing stations described herein can perform up to four different process operations within a single module. By simultaneously polishing a substrate and cleaning the pad, overhead time can be reduced. Pad cleaning and head cleaning can also be improved by increasing the cleaning time for both components.

[0111] While the forgoing 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, the scope of the disclosure being defined by the following claims.

Claims

1. 1. A substrate polishing system comprising: a plurality of polishing stations positioned in a stacked arrangement; Each of the polishing stations comprises: a system body including one or more walls defining a processing region; a platen disposed within the processing region of the system body and having a rectangular pad support surface configured to accommodate a non-axisymmetric polishing pad, the long side of the rectangular pad support surface being aligned in a first direction; a head assembly disposed above the pad support surface of the platen; the head assembly includes: a carrier head positioned above the pad support surface of the platen; a linear actuator connected to the center rail support; a support arm connecting the carrier head to the linear actuator; Including, the linear actuator is configured to position the carrier head and the support arm in the first direction. Substrate polishing system.

2. 2. The substrate polishing system of claim 1, wherein the processing regions of each of the plurality of vertically stacked polishing stations are isolated from each other.

3. the platen includes a first platen, and the substrate polishing system includes:

3. The substrate polishing system of claim 2, further comprising a second platen disposed within the system body and having a rectangular pad support surface configured to accommodate a non-axisymmetric polishing pad, the second platen having a long side of the rectangular pad support surface aligned in the first direction.

4. 4. The substrate polishing system of claim 3, wherein the first platen and the second platen each have a length and width aspect ratio greater than about 2:

1.

5. a first pad drive unit configured to align a first non-axisymmetric polishing pad mounted on a first side of the first platen to a second side of the first platen opposite the first side; a second pad drive unit configured to align a first non-axisymmetric polishing pad disposed on a first side of the second platen to a second side of the second platen opposite the first side; a pad cleaning module including one or more fluid nozzles and positioned on the second side of the first platen or the second platen; The substrate polishing system of claim 3 further comprising:

6. a pad drive unit configured to align a first non-axisymmetric polishing pad mounted on a first side of the platen to a second side of the platen opposite the first side, the carrier head being positioned over the first side of the platen including the pad support surface; a pad cleaning module including one or more fluid nozzles and disposed on the second side of the platen; The substrate polishing system of claim 1 , further comprising:

7. The substrate polishing system of claim 6 , wherein a pad conditioner is mounted on the second side of the platen.

8. a pad conditioner disposed on a conditioning side of the platen opposite the polishing side of the platen, the polishing side of the platen including the rectangular pad support surface; a linear conditioner actuator; a connecting arm connected between the linear conditioner actuator and the pad conditioner; Furthermore, The substrate polishing system of claim 1 , wherein the linear conditioner actuator is configured to position the pad conditioner and the connecting arm in the first direction.

9. 2. The substrate polishing system of claim 1, wherein the plurality of polishing stations comprises two polishing stations that are vertically stacked and include processing regions that are fluidly isolated from one another.

10. 10. The substrate polishing system of claim 9, wherein the two polishing stations have a height of less than about 1000 mm and a width of less than about 2500 mm.

11. 2. The substrate polishing system of claim 1, wherein the linear actuator is the only means for generating relative motion between the carrier head and the non-axisymmetric polishing pad mounted on the rectangular pad support surface.

12. 1. A substrate polishing system configured for use during semiconductor manufacturing, comprising: a system body including one or more walls defining a processing region; a first platen disposed within the processing region of the system body; a second platen disposed within the processing region of the system body; a center rail support positioned between the first platen and the second platen within a processing area of ​​the system body; a first head assembly disposed above one of the first platen or the second platen, a first carrier head; and a first support arm coupling the first carrier head to the center rail support; a first head assembly including: a second head assembly disposed above one of the first platen or the second platen, a second carrier head; and a second support arm coupling the second carrier head to the center rail support; a second head assembly including: A substrate polishing system comprising:

13. 13. The substrate polishing system of claim 12, wherein the first head assembly further includes a first rotating shaft positioned at an inner end of the first support arm opposite the first carrier head, and the second head assembly further includes a second rotating shaft positioned through an inner end of the second support arm opposite the second carrier head.

14. 13. The substrate polishing system of claim 12, wherein at least one pad drive unit is configured to align one or more polishing pads mounted on the first platen and the second platen.

15. the first platen is configured to have a first pad coupled to a first side facing toward the first carrier head and a second pad coupled to a second side facing away from the first carrier head, and the second platen is configured to have a third pad coupled to a third side facing toward the second carrier head and a fourth pad coupled to a fourth side facing away from the second carrier head. The substrate polishing system of claim 14.

16. a first pad cleaning station and a second pad cleaning station disposed on the opposite side of the first platen from either the first head assembly or the second head assembly; The substrate polishing system of claim 12 further comprising:

17. 17. The substrate polishing system of claim 16, wherein the first pad cleaning station further comprises a first pad conditioner and the second pad cleaning station further comprises a second pad conditioner.

18. 13. The substrate polishing system of claim 12, wherein the central rail support includes a first rail on a first side and a second rail on a second side, whereby the first head assembly is coupled to the first rail and the second head assembly is coupled to the second rail.

19. the center rail support is coupled to a wall of the system body; a linear actuator; a central rotating shaft connected to the linear actuator and having a central rotation axis, wherein both the first head assembly and the second head assembly are coupled to the central rotating shaft; The substrate polishing system of claim 12 further comprising:

20. The substrate polishing system of claim 12 , further comprising one or more liquid supply units configured to supply one or more of a slurry, a conditioning fluid, or water.

Images