Apparatus and method for in-situ chemical separation and recirculation in a chemical mechanical processing system

Abstract

Apparatus and methods for in-situ chemical separation and recirculation in a chemical mechanical processing system are provided. In one aspect, a chemical mechanical planarization system includes a polishing platen having a surface configured to polish a substrate, and a slurry delivery system configured to deliver slurry to the surface of the polishing platen. The apparatus can also include an effluent capture device configured to capture slurry from the polishing platen, filter the captured slurry, and provide the filtered slurry to the slurry delivery system.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to U.S. Provisional Patent Application No. 63 / 608,749, filed December 11, 2023, the disclosure of which is incorporated herein by reference in its entirety. Any and all applications that identify foreign or domestic priority claims in PCT requests filed together with this application are incorporated herein by reference. Technical Field

[0003] This disclosure generally relates to in-situ chemical separation and recirculation in a chemical mechanical planarization (CMP) system. Background Technology

[0004] During chemical mechanical planarization or polishing (CMP), abrasives and acidic or alkaline slurries are applied to a rotating polishing pad / disc. The wafer is held by a wafer carrier that rotates and presses against the polishing disc for a specified period of time. During the CMP process, the wafer is polished or planarized by grinding and etching. Therefore, slurry delivery and used slurry collection can be important considerations in CMP system design. Summary of the Invention

[0005] For the purpose of outlining the advantages of this disclosure and its implementation relative to existing technologies, certain objects and advantages of this disclosure are described herein. Not all of these objects or advantages can be achieved in any particular embodiment. Therefore, for example, those skilled in the art will recognize that the invention may be embodied or performed in a manner that realizes or optimizes one or more advantages as taught herein, without necessarily achieving other objects or advantages as may be taught or suggested herein.

[0006] One aspect of the disclosed technology is a chemical mechanical planarization (CMP) system, comprising: a polishing disc having a surface configured to polish a substrate; a slurry delivery system configured to deliver slurry to the surface of the polishing disc; and a slurry recirculation system configured to capture slurry from the polishing disc, filter the captured slurry, and provide the filtered slurry to the slurry delivery system.

[0007] In some embodiments, the slurry recirculation system includes: an effluent capture device including a capture tank configured to capture slurry flowing from the edge of a polishing disc; a discharge system configured to receive the captured slurry from the capture tank; and a recovery system configured to receive the captured slurry from the discharge system and filter the captured slurry.

[0008] In some embodiments, the discharge system includes a used slurry inlet, comprising a first discharge pipe configured to receive captured slurry from a capture tank and a second discharge pipe configured to receive a mixture of chemicals and deionized water flowing from components of the CMP system other than the polishing turntable.

[0009] In some embodiments, the discharge system includes a valve and a control system configured to direct the captured slurry to a main discharge pipe when substrate processing begins, and to redirect the captured slurry to a recycling system after a predetermined length of time since substrate processing began.

[0010] In some embodiments, the recovery system includes: a coarse filter configured to perform a first filtration on the captured slurry; a fine filter configured to receive the captured slurry from the coarse filter and perform a second filtration on the captured slurry; and a slurry return device configured to receive the captured slurry from the fine filter and return the captured slurry to a slurry delivery system.

[0011] In some embodiments, the recycling system further includes: a slurry supply device configured to supply new slurry and additives; and a mixer configured to receive captured slurry from a fine filter and new slurry and additives from the slurry supply device, mix the captured slurry with the new slurry and additives, and provide the captured slurry mixed with the new slurry and additives to a slurry return device.

[0012] In some embodiments, the recycling system further includes a metering controller configured to regulate the amount of new slurry and additives supplied from the slurry supply device to the mixer.

[0013] In some embodiments, the metering controller is further configured to: determine a removal rate of the processed substrate; determine that the difference between the removal rate and a specified removal rate is greater than a predetermined threshold; and adjust the amount of new slurry and / or additives supplied to the mixer in response to determining that the difference between the removal rate and the specified removal rate is greater than the predetermined threshold.

[0014] In some embodiments, the recycling system further includes one or more sensors configured to measure one or more characteristics of the captured slurry output from the fine filter, wherein the metering controller is configured to adjust the amount of new slurry and / or additives supplied to the mixer based on the measured one or more characteristics.

[0015] On the other hand, there is a slurry recirculation system, comprising: an effluent capture device including a capture tank configured to capture slurry flowing from the edge of a polishing turntable of a chemical mechanical planarization (CMP) system; an discharge system configured to receive the captured slurry from the capture tank; and a recovery system configured to receive the captured slurry from the discharge system and filter the captured slurry, the recovery system including a slurry return device configured to return the filtered slurry to the slurry delivery system of the CMP system.

[0016] In some embodiments, the discharge system includes a used slurry inlet, comprising a first discharge pipe configured to receive captured slurry from a capture tank and a second discharge pipe configured to receive a mixture of chemicals and deionized water flowing from components of the CMP system other than the polishing turntable.

[0017] In some embodiments, the discharge system includes a valve and a control system configured to direct the captured slurry to a main discharge pipe when substrate processing begins, and to redirect the captured slurry to a recycling system after a predetermined length of time since substrate processing began.

[0018] In some embodiments, the recovery system includes: a coarse filter configured to perform a first filtration on the captured slurry; and a fine filter configured to receive the captured slurry from the coarse filter and perform a second filtration on the captured slurry, wherein the slurry return device is further configured to receive the captured slurry from the fine filter.

[0019] In some embodiments, the recycling system further includes: a slurry supply device configured to supply new slurry and additives; and a mixer configured to receive captured slurry from a fine filter and new slurry and additives from the slurry supply device, mix the captured slurry with the new slurry and additives, and provide the captured slurry mixed with the new slurry and additives to a slurry return device.

[0020] In some embodiments, the recycling system further includes:

[0021] A metering controller configured to regulate the amount of new slurry and additives supplied from the slurry supply unit to the mixer.

[0022] In some embodiments, the metering controller is further configured to: determine a removal rate of the processed substrate; determine that the difference between the removal rate and a specified removal rate is greater than a predetermined threshold; and adjust the amount of new slurry and / or additives supplied to the mixer in response to determining that the difference between the removal rate and the specified removal rate is greater than the predetermined threshold.

[0023] In some embodiments, the recycling system further includes one or more sensors configured to measure one or more characteristics of the captured slurry output from the fine filter, wherein the metering controller is configured to adjust the amount of new slurry and / or additives supplied to the mixer based on the measured one or more characteristics.

[0024] Another aspect is a method for capturing and reusing slurry from a chemical mechanical planarization (CMP) system, comprising: polishing a substrate on a surface using a polishing disc of a CMP system; delivering slurry to the surface of the polishing disc; capturing the slurry from the polishing disc; filtering the captured slurry; and providing the filtered slurry to a slurry delivery system for the CMP system.

[0025] In some embodiments, the method further includes: capturing slurry flowing from the edge of the polishing turntable via a capture tank; causing the captured slurry to flow from the capture tank into a discharge system; receiving the captured slurry from the discharge system at a recovery system; and filtering the captured slurry at the recovery system.

[0026] In some embodiments, the discharge system includes a used slurry inlet, which includes a first discharge pipe and a second discharge pipe, and the method further includes: receiving captured slurry from a capture tank using the first discharge pipe; and receiving a mixture of chemicals and deionized water flowing out from components of the CMP system other than the polishing turntable using the second discharge pipe.

[0027] In some embodiments, the method further includes: guiding the captured slurry to a main discharge pipe when the substrate is being processed; and redirecting the captured slurry to a recycling system after a predetermined period of time has elapsed since the substrate was started.

[0028] In some embodiments, the method further includes: performing coarse filtration of the captured slurry; performing fine filtration of the captured slurry; and returning the captured slurry to the slurry delivery system after coarse and fine filtration.

[0029] In some embodiments, the method further includes: supplying new slurry and additives using a slurry supply device; receiving captured slurry and additives from the slurry supply device after coarse and fine filtration at a mixer; mixing the captured slurry with the new slurry and additives using a mixer; and providing the captured slurry mixed with the new slurry and additives to a slurry delivery system.

[0030] In some embodiments, the method further includes adjusting the amount of new slurry supplied from the slurry supply device to the mixer and the amount of additives.

[0031] In some embodiments, the method further includes: determining a removal rate of the processed substrate; determining that the difference between the removal rate and a specified removal rate is greater than a predetermined threshold; and adjusting the amount of new slurry and / or additives supplied to the mixer in response to determining that the difference between the removal rate and the specified removal rate is greater than the predetermined threshold.

[0032] In some embodiments, the method further includes: measuring one or more characteristics of the captured slurry from the fine filtration output of the captured slurry, wherein the amount of new slurry and / or additives supplied to the mixer is further adjusted based on the measured one or more characteristics. Attached Figure Description

[0033] The above and additional objects, features, and advantages of the disclosed technology will be better understood from the following illustrative and non-limiting detailed description of certain embodiments thereof, with reference to the accompanying drawings. In the drawings, the same reference numerals will be used for the same elements unless otherwise stated.

[0034] Figure 1 This is a schematic diagram of a substrate processing system, showing a substrate carrier that holds the substrate in the processing position.

[0035] Figure 2 yes Figure 1 A view of the substrate processing system, showing the substrate carrier holding the substrate in the loading position.

[0036] Figure 3 This is a partial cross-sectional view of the substrate carrier head, which may include, as... Figure 1 and Figure 2 A portion of the substrate carrier shown.

[0037] Figure 4A and Figure 4B An effluent capture device for a CMP system according to various aspects of this disclosure is shown.

[0038] Figure 5 An emission system according to various aspects of this disclosure is shown, which includes an emission pipe and a control valve configured to be coupled to an effluent capture device.

[0039] Figures 6A to 6C Another embodiment of the emission system 600 according to various aspects of this disclosure is shown.

[0040] Figure 7 This is a block diagram illustrating the connection of various aspects of the present disclosure between the discharge pipe and the control valve and the slurry delivery system for the recovery system.

[0041] Figure 8This is an example method, according to various aspects of the present disclosure, for monitoring the removal rate of multiple wafers and adjusting the recycled slurry returned to the CMP system.

[0042] Figure 9 These are example methods for capturing and reusing slurry from a CMP system, which can be executed by a CMP system according to various aspects of this disclosure. Detailed Implementation

[0043] Although the following text sets forth detailed descriptions of many different embodiments of the invention, it should be understood that the legal scope of the invention is defined by the words of the claims set forth at the end of this patent. The detailed description is to be construed as exemplary only and does not describe every possible embodiment of the invention, as describing every possible embodiment would be impractical, if not impossible. Many alternative embodiments may be implemented using current technology or technology developed after the date of this patent application, which still fall within the scope of the claims defining the invention.

[0044] Chemical mechanical planarization (CMP)

[0045] Chemical mechanical planarization (CMP) for thin film planarization is common among companies manufacturing the “chips” for these types of devices, including semiconductor ICs, MEMS devices, LEDs, and many other similar applications. This adoption includes the manufacture of chips for mobile phones, tablets, and other portable devices, as well as desktop and laptop computers. Advances in nanotechnology and microfabrication have brought immense promise for the widespread use and adaptation of digital devices in the medical, automotive, and Internet of Things (“IoT”) fields. Chemical mechanical planarization for thin film planarization was invented and developed by scientists and engineers at IBM in the early 1980s. Today, the process is widely used globally and is one of the truly enabling technologies in the manufacture of many digital devices.

[0046] Integrated circuits are fabricated as multiple and alternating layers of conductive materials (e.g., copper, tungsten, aluminum, etc.), insulating layers (e.g., silicon dioxide, silicon nitride, etc.), and semiconductor materials (e.g., polysilicon). These layers are sequentially applied to the wafer surface, but due to implanted devices on the surface, topographic undulations are created in the device structure, as in the case of silicon dioxide insulating layers. Before the next layer can be deposited, CMP is typically used to flatten or “planarize” these unwanted topographic undulations to allow proper interconnection between increasingly smaller device features. In the case of copper layers, copper is deposited on the surface to fill contact vias and create efficient vertical paths for electron transfer between devices and between layers. This process continues for each applied layer (typically applied via a deposition process). In the case of multilayer conductive materials (multilayer metals), this may result in numerous polishing procedures (one for each layer of conductor, insulator, and semiconductor material) to achieve successful circuitry and interconnection between device features.

[0047] During the CMP process, the substrate or wafer is held by a wafer carrier, which rotates and is typically pressed against a polishing turntable by an elastic membrane within the wafer carrier for a specified period of time. CMP wafer carriers typically incorporate components on the processing head for the precision polishing of typically flat and circular workpieces (e.g., silicon wafers and / or films deposited thereon). These components include: 1) an elastic membrane to which compressed gas is applied to the top or back surface; the pressure is then transmitted through the membrane to the top or back surface of the workpiece to achieve material removal during CMP; and 2) one or more rigid support components that provide means for: securing the membrane to its mating components, maintaining the membrane to its desired shape and size, and / or clamping the membrane to provide a sealed volume for sealing and containing controlled gas pressure.

[0048] In this process, slurry is applied to a rotating polishing pad via a fluid control device (e.g., a metering pump or mass flow control regulator system). The slurry can be delivered to the polishing disc in a single-pass distribution system. For better performance, the slurry particles in the medium should be uniformly distributed between the rotating wafer and the rotating polishing pad / disc.

[0049] A wafer carrier film applies force to the back side of the wafer to press it into a pad, and both can have movement to generate relative velocity. This movement and force cause some portions of the pad to abrade the substrate by pushing the abrasive against it as the pad moves across the wafer surface. Corrosive chemicals in the slurry alter the material being polished on the wafer surface. This mechanical effect, combining abrasion with chemical alteration, is called chemical mechanical planarization or polishing (CMP). Using both chemical and mechanical effects simultaneously can easily increase the material removal rate by an order of magnitude compared to using either chemical or mechanical effect alone. Similarly, the smoothness of the polished surface can be improved by using both chemical and mechanical effects together.

[0050] Next-generation chemical mechanical processing (CMP) tools are designed to utilize sophisticated slurry chemicals. Examples of these slurry chemicals include, but are not limited to, potassium permanganate (KMnO4), sodium permanganate (NaMnO4), and permanganate-free rock salt-based slurries (MXO2, where M is an alkali metal and X is a halogen). One example of a permanganate-free rock salt-based slurry is sodium chlorite (NaClO2). These chemicals are relatively very expensive and can flow into the CMP system (also known as the processing tool) over a relatively long time (e.g., 10–30 minutes). These sophisticated slurry chemicals can outperform previous slurry chemicals by providing, for example, relatively high and / or more consistent removal rates while achieving less substrate scratching than conventional diamond-based slurries. As used herein, “chemicals” can refer to the chemical / particulate composition of the slurry and / or any chemicals / particulates / contaminants (e.g., materials removed from the surface of the polished substrate) generated by other components of the CMP system.

[0051] Due to the cost of these slurry chemicals, it is desirable to recycle used slurry, which may involve separating the used slurry from other chemicals and deionized water flowing simultaneously on the CMP system.

[0052] During the polishing process, materials such as copper, dielectrics, or polysilicon are removed from the surface of the wafer. These microscopic particles may remain suspended in the slurry, become embedded in the polishing pad, or both. These particles scratch the surface of the polished film and thus cause catastrophic failures in the circuitry, rendering the chip unusable and becoming a major negative impact on yield. Therefore, in order to reuse slurry chemicals, it is desirable to remove these particles and any other potential contaminants from the slurry chemicals so that the recovered slurry chemicals can be reused without introducing a significant risk of damaging the wafer being polished.

[0053] The disclosed technology will be described with reference to specific embodiments and certain accompanying drawings. This disclosure is not limited thereto, but is limited only by the claims. The described drawings are illustrative only and not restrictive. In the drawings, the dimensions of some elements may be exaggerated and not drawn to scale for illustrative purposes. Dimensions and relative dimensions do not necessarily correspond to actual reductions in practice of this disclosure.

[0054] CMP system with liquid cooling

[0055] Figure 1 This is a schematic diagram of a chemical mechanical planarization (CMP) system 100 for processing a polishing pad 110. The CMP system 100 may include a polishing pad 110, a turntable 120, a slurry delivery system 140, a substrate carrier 150, and a pad adjustment arm 160. In some embodiments, the CMP system 100 further includes components as shown in FIG4 to FIG5. Figure 7 A more detailed description of the slurry recirculation system 200.

[0056] The wafer carrier 150 can be configured to hold and process wafers. It should be understood that the term "wafer" as used herein can refer to a semiconductor wafer (e.g., circular), but can more broadly include other types of substrates with different shapes processed by polishing or planarization equipment (e.g., CMP equipment). Therefore, throughout this application, the terms "wafer" and "substrate" are used interchangeably unless the context explicitly refers to "wafer" specifically as "substrate." In the illustrated embodiment, the substrate carrier 150 is in a processing (e.g., below) position, thereby holding the substrate (not shown) against a polishing pad 110 with a film (not shown). The polishing pad 110 can be positioned on a support surface, such as the surface of the turntable 120.

[0057] Figure 2 yes Figure 1 A view of a CMP system 100, showing a substrate 155 held in a loaded (e.g., on) position by a substrate carrier 150. The substrate 155 can be held, for example, by a vacuum force. Reference Figure 1 and Figure 2 Both, the slurry delivery system 140 can be configured to deliver processing slurry to the substrate 155 and allow the substrate 155 to be chemically / mechanically planarized against the polishing pad 110. In some embodiments, the slurry delivery system 140 may obtain slurry from a slurry source (not shown). The pad adjustment arm 160 may include a pad adjuster at the end of the pad adjustment arm 160. The pad adjuster may be configured to process or "refresh" the surface roughness or other processing characteristics of the pad during or between processing cycles.

[0058] exist Figure 1 and Figure 2 In the CMP system 100, the polishing pad 110 can be located on the top surface of the turntable 120, which rotates counterclockwise about a vertical axis. Other orientations and directions of movement can be achieved.

[0059] The slurry delivery system 140 delivers a slurry containing abrasive and corrosive particles to the surface of the polishing pad 130 being processed. The polishing slurry is typically a colloidal suspension of abrasive particles (i.e., colloidal silica, colloidal alumina, or colloidal cerium dioxide) in an aqueous medium. In various embodiments, the slurry delivery system 140 includes a metering pump, a mass flow control system, or other suitable fluid delivery components.

[0060] Capturing and reusing complex slurry chemicals for next-generation CMP systems can be advantageous. This allows for the use of more expensive slurry chemicals while reducing overall costs by reusing at least a portion of the captured slurry.

[0061] The substrate carrier 150 may, for example, hold the substrate 155 under vacuum such that the surface of the substrate 155 to be polished faces the polishing pad 110. Abrasive particles and corrosive chemicals in the slurry deposited on the polishing pad 110 by the slurry delivery system 140 mechanically and chemically polish the substrate by abrasion and corrosion, respectively. The substrate carrier 150 and the polishing pad 110 may be moved relative to each other in any of a variety of different ways to provide polishing. For example, the substrate carrier 150 may apply a downward force to the turntable 120, pressing the substrate 155 against the polishing pad 110. The substrate 155 may be pressed against the polishing pad 110 using a pressure film (not shown), as will be further described herein. As the polishing pad 110 and the substrate carrier 150 move relative to each other, the abrasive particles and corrosive chemicals in the slurry between the substrate 155 and the polishing pad 110 provide both chemical and mechanical polishing. The relative motion between the polishing pad and the substrate carrier can be configured in various ways, and either or both can be configured to oscillate, move linearly and / or rotate relative to each other in a counterclockwise and / or clockwise manner.

[0062] The pad adjustment arm 160 can adjust the surface of the polishing pad 110 by pressing it against the polishing pad 110, wherein there is relative movement between them, such as the relative movement described above with respect to the polishing pad and the substrate carrier 150. The pad adjustment arm 160 in the illustrated embodiment can oscillate and has a rotating pad adjuster at its end that contacts the polishing pad 110.

[0063] Figure 3 This is a partial cross-sectional view of the substrate carrier head 300, which may be included as... Figure 1 and Figure 2 This is a portion of the substrate carrier 150 shown. The substrate carrier head 300 includes a membrane assembly 305 for a chemical mechanical planarization (CMP) system. In some embodiments, the substrate carrier head 300 (also referred to herein as a carrier head) may include a support base 380 to which the membrane assembly 305 is mounted. The support base 380 may be any suitable configuration to provide support to the membrane assembly. The support base 380 may attach and engage the remainder of the substrate carrier head 300 to a CMP system (not shown). The support base 380 may include a carrier body, a substrate holder, a support plate, and / or other components described elsewhere herein to support the wafer (e.g., membrane assembly 305) and / or engage the remainder of the carrier head 300 to the CMP system.

[0064] As shown in the figure, membrane assembly 305 may include a support plate 310, an elastic membrane 320, a membrane retainer (e.g., a membrane clamp 330), and an optional external pressure ring 340. The support plate 310 can be any suitable configuration for supporting the wafer during processing, such as attaching membrane assembly 305 to a support base 380. For example, the support plate 310 can be mounted to the support base 380 using one or more bolts or other suitable attachment elements. The support plate 310 can be mounted to the support base 380 at various locations, such as along the outer periphery of the support base 380.

[0065] The support plate 310 can be any suitable configuration to support the wafer, for example, via the elastic membrane 320. The elastic membrane 320 can be secured to the support plate 310 in a variety of different ways. The elastic membrane 320 can be secured to the support plate 310 before or after it is secured to the support base 380. The elastic membrane 320 can be secured to the support plate 310 using any of a variety of suitable membrane retainers (e.g., membrane clips 330). In some embodiments, the membrane clip 330 can be spring-loaded. In other embodiments, the membrane clip 330 can be securely fastened using fastening mechanisms such as nuts and bolts. The membrane clip 330 can secure the outer portion (e.g., the outer edge) of the membrane 320 to a corresponding portion of the support plate 310 and / or the support base 380. The membrane retainer can be any suitable construction to secure at least a portion of the membrane 320 to the support plate 310 and / or the support base 380.

[0066] The elastic membrane 320 can be fixed to the support plate 310, so that the membrane 320 can hold the substrate 370 against the polishing pad and process the substrate, for example, as described above. Figures 1 to 2Description. The membrane may include a first surface (e.g., downward-facing) configured to contact a surface of the substrate (e.g., upward-facing). The membrane 320 may be sufficiently elastic and flexible such that, combined with the polishing pad material and process parameters, the membrane 320 can apply more uniform pressure across the entire substrate 370. In some embodiments, the elasticity and flexibility of the membrane 320 may also help reduce substrate breakage. The membrane 320 and the support plate 310 may be configured to allow liquid to flow between the membrane 320 and the support plate 310 and to press the membrane 320 against the substrate 370 during planarization. For example, the membrane 320 may be configured to allow liquid to flow along a second surface (e.g., the upward-facing surface) opposite the first membrane surface described above. The support plate 310 may be spaced apart from the membrane 320 to form a gap or membrane cavity 360 therebetween. The membrane cavity 360 may be formed when the membrane 320 is in a static (e.g., unpressurized) state. The membrane cavity 360 may be sealed. In some embodiments, a liquid-tight seal may be formed within the membrane cavity 360 to prevent liquid leakage from the membrane cavity 360 when the liquid is pressurized. Therefore, membrane cavity 360 can form a liquid cavity through which liquid can flow. A seal can be formed between a portion of membrane 320 and a portion of the carrier body (e.g., plate 310 and / or base 380), for example at membrane clamp 330. As used herein, a sealed membrane cavity includes a membrane cavity in fluid communication with an inlet and / or outlet that can be selectively sealed (e.g., opened and closed by a valve).

[0067] Example systems and methods for in-situ chemical separation and recirculation

[0068] As mentioned above, next-generation CMP tools are being designed to utilize complex slurry chemicals. These chemicals are relatively very expensive and can flow into the CMP system over a relatively long period of time (e.g., 10-30 minutes). Such complex slurry chemicals can be advantageous compared to previous slurry chemicals by providing, for example, higher and / or more consistent removal rates.

[0069] Various aspects of this disclosure relate to equipment and techniques for recycling at least a portion of slurry used in CMP. As described herein, the process may involve separating the used slurry from other chemicals and deionized water flowing simultaneously on the CMP system. Because slurry chemicals can be relatively expensive, recycling slurry can provide cost savings and environmental benefits by disposing of less slurry as waste.

[0070] To address the aforementioned problems, various aspects of this disclosure relate to a slurry recirculation system 200 configured to capture and recover slurry from a CMP system (e.g., Figure 1 and / or Figure 2The CMP system 100 uses at least a portion of the slurry. In some embodiments, the CMP system may include a slurry recirculation system 200 as a component of the system. In some embodiments, the slurry recirculation system 200 may be a separate device configured to be coupled to the CMP system.

[0071] The slurry recirculation system 200 may include an effluent capture device (e.g., the effluent capture device 400 of FIG4), a discharge system (e.g. Figure 5 500 or Figures 6A to 6C The emission system 600) and the recycling system (e.g. Figure 7 The recovery system 700). As described herein, the effluent capture device can be configured to capture slurry and / or other effluents from the CMP system, the discharge system can be configured to receive the captured effluents from the effluent capture device, and the recovery system can be configured to recover at least a portion of the captured slurry.

[0072] The effluent capture device of the slurry recirculation system 200 may have a discharge pipe (e.g., a coaxial discharge pipe), effluent capture and control system equipment, which is capable of recovering at least a portion of the slurry chemicals. Figure 4A and Figure 4B This disclosure illustrates aspects of a CMP system (e.g., Figure 1 or Figure 2 Example embodiment of the effluent capture device 400 of the system 100.

[0073] refer to Figure 4A and Figure 4B The effluent capture device 400 includes a surrounding polishing disc 405 (e.g., Figure 1 and 2 The rotary table 120 includes a chemical substance capture tank 420 and an outlet 430 configured to deliver fluid to a discharge system. For example, outlet 430 may deliver fluid to a discharge system, such as discharge system 500, as described herein. Figure 5 Further illustration and discussion are provided. A slurry chemical flow path 410 is also shown, which may include a mixture of slurry chemicals and deionized (DI) water, the mixture flowing to the edge of the polishing disc 405 and into the chemical trap 420. For clarity, the polishing disc 405 is shown schematically and transparently relative to the other components shown.

[0074] When the CMP system begins the CMP process, as a result of the CMP process, a mixture of slurry chemicals and deionized water is generated on the polishing turntable 405. This mixture is then transported via a slurry delivery system (e.g., Figure 2The slurry delivery system 140 introduces slurry onto the polishing disc 405. The slurry flows across the polishing disc 405 (e.g., from the center to the edge of the polishing disc 405), pushing the slurry chemicals and deionized water to the outer edge of the polishing disc 405, as shown by the chemical flow path 410. A chemical trap 420 traps the mixture flowing out from the edge of the polishing disc 405 and allows the mixture to flow from the trap 420 into the outlet 430.

[0075] Figure 5 An emission system 500 according to various aspects of this disclosure is shown, comprising an emission pipe and a control valve configured to be coupled to an effluent capture device. Specifically, Figure 5 A cross-sectional view of the emission system 500 is provided.

[0076] like Figure 5 As shown, the discharge system 500 includes a used slurry inlet 540, a recovery valve 570, a drain valve 550, a main discharge pipe 560, and a control system 530. A first mixture 505 of chemicals and deionized water is received at the used slurry inlet 540 from the outlet 430 of the effluent capture device 400. The used slurry inlet 540 includes a first discharge pipe 541 (also referred to as an inner discharge pipe) coaxial with a second discharge pipe 543 (also referred to as an outer discharge pipe). In some embodiments, the first discharge pipe 541 and the second discharge pipe 543 may have different non-coaxial arrangements, for example, positioned at different locations relative to the CMP system.

[0077] An internal discharge pipe 541 receives a first mixture 505, and an external discharge pipe 543 receives a second mixture 510 of chemicals and deionized water, originating from (e.g., flowing out of) components in the CMP system other than the polishing turntable 405. For example, the second mixture 510 of chemicals and deionized water may flow from a carrier cleaning station and / or various rinsing and spray nozzles configured to keep the wafers and internal components of the CMP system 100 moist. This second mixture may be collected, for example, by a separate capture tank and / or inclined surface or other collection device within the CMP system, which is supplied to the external discharge pipe 543. The external discharge pipe 543 and / or the internal discharge pipe 541 may be in fluid communication (e.g., selective fluid communication) with the main discharge pipe 560. For example, a used slurry inlet 540 is connected to a drain valve 550 and a recovery valve 570. A control system 530 is configured to control the drain valve 550 to open at the start of CMP processing to remove chemicals and deionized water generated before the slurry is supplied to the polishing turntable 405. The open drain valve 550 supplies chemicals and deionized water to the main drain pipe 560. After sufficient amounts of chemicals and deionized water have been removed, the first mixture 505 of chemicals and deionized water flowing through the inner drain pipe 541 of the used slurry inlet 540 may be substantially slurry (e.g., the slurry may be substantially free of contaminants). That is, the first mixture 505 of chemicals and deionized water included in the slurry received from outlet 430 after the CMP process has reached a steady state may be less than a predetermined threshold.

[0078] The control system 530 is configured to control the recovery valve 570 to open and control the drain valve 550 to close, so as to redirect the received chemical substance and the first mixture 505 of deionized water to Figure 7 The recovery system 700 is shown. In some embodiments, the control system 530 is configured to redirect the slurry to the recovery system 700 after a predetermined length of time has elapsed since the start of the CMP process. However, aspects of this disclosure are not limited thereto, and in some embodiments, the control system 530 may use one or more sensors (not shown) to measure the slurry to confirm that the amount of chemicals and / or deionized water is below a threshold level before redirecting the slurry to the recovery system 700.

[0079] Figures 6A to 6C Another embodiment of the emission system 600 according to various aspects of this disclosure is shown. In particular, Figure 6A A perspective view of the emission system 600 is provided. Figure 6B A partial cross-section of the emission system 600 is shown, and Figure 6C A side view of the emission system 600 is shown.

[0080] like Figures 6A to 6CAs shown, the discharge system 600 includes a used slurry inlet 640, a valve 650, a main discharge pipe 660, and a control system 630. Figures 6A to 6C The emission system 600 can be basically similar to the emission system 500. Figure 5 In this system, the drain valve 550 and recovery valve 570 are replaced by a combination valve 650. Valve 650 is configured to redirect a mixture of chemicals and deionized water received from the outlet 430 of the effluent capture device 400 back to the main discharge pipe 660 or the recovery system 700. The components of the discharge system 600 function similarly in other respects to... Figure 5 The corresponding component in.

[0081] Figure 7 An embodiment of a recovery system 700 is shown, which can be coupled to an emission system, such as emission system 500 or 600. For example, the recovery system 700 can be coupled to a control valve (e.g., Figure 5 Recovery valve 570 or Figures 6A to 6C Valve 650) and slurry delivery system (e.g. Figure 1 Between the slurry conveying system 140).

[0082] like Figure 7 As shown, the recovery system 700 includes a coarse filter 710, a fine filter 720, a mixer 730, a slurry supply device 740, a metering controller 750, and a slurry return device 760. It should be understood that, although... Figure 7 The components shown are schematic, but any components compatible with those used in CMP slurry recovery processes can be implemented. Coarse filter 710 receives used slurry from recovery valve 570 or valve 650. Coarse filter 710 performs initial filtration of the slurry using coarse filtration. Fine filter 720 receives the coarsely filtered slurry from coarse filter 710 and performs secondary filtration of the slurry using fine filtration. Although the illustrated embodiment of recovery system 700 includes both coarse filter 710 and fine filter 720, in other embodiments, recovery system 700 may include a single filter or three or more filters.

[0083] The slurry supply device is configured to provide: pH spike additive 742, abrasive 744, fresh slurry 746, and / or other additives to be mixed into the slurry to be filtered. In some embodiments, the slurry supply device 740 can supply slurry from a supply... Figure 1 and Figure 2The slurry delivery system 140 receives fresh slurry 746 from its slurry source. The mixer 730 is configured to receive finely filtered slurry from the fine filter 720 and pH spike additive 742, abrasive 744, and / or fresh slurry 746 from the slurry supply device 740. The mixer 730 is configured to mix the filtered used slurry with the fresh slurry 746, pH spike additive 742, and / or abrasive 744. The mixture of the filtered used slurry and any additives and / or fresh slurry is then returned via the slurry return device 760 to another part of the CMP system (e.g., to a polishing turntable, e.g., via the slurry delivery system 140), allowing the slurry to be reused for CMP processing. The slurry return can be any suitable configuration that allows fluid communication (e.g., controlled and / or selective communication, e.g., valves, flow controllers, etc.) between the mixer and another part of the CMP system for slurry reuse.

[0084] The metering controller 750 is configured to regulate the amount of new slurry 746 and / or additives (e.g., pH spike additive 742, abrasive 744, etc.) supplied to the mixer 730 to ensure that the slurry returned to the CMP system has substantially consistent chemical properties (e.g., the variation in the chemical composition of the returned slurry does not exceed a threshold amount). Therefore, the returned slurry is configured to maintain a substantially consistent removal rate (e.g., a removal rate variation not exceeding a threshold amount) during the polishing of multiple wafers.

[0085] In other embodiments, the metering controller 750 is configured to measure the metered thickness of the wafer being processed by the CMP system 100 to determine the wafer removal rate. For example, in some embodiments, the wafer thickness before CMP processing can be compared to the wafer thickness after CMP processing to determine the total thickness removed during the process. The removal rate can be determined based on the amount of thickness removed. (As in...) Figure 8 The metering controller 750 can use the removal rate to adjust the amount of pH spike additive 742, abrasive 744, fresh slurry 746 and / or other additives to be supplied to the mixer 730.

[0086] In some embodiments, the metering controller 750 is configured to measure the characteristics of the finely filtered slurry to adjust the amount of pH spike additive 742, abrasive 744, fresh slurry 746, and / or other additives to be supplied to the mixer 730. For example, in some embodiments, the fine filter 720 may include one or more sensors (e.g., conductivity sensors) 722 configured to measure the pH, abrasive amount, and / or other characteristics of the finely filtered slurry. In other embodiments, the sensors may be located downstream of the fine filter 720 and / or as part of the metering controller 750, wherein a portion of the filtered slurry is diverted to the sensors for measurement.

[0087] Figure 8 This is an example method 800, which can be performed by a CMP system 100 according to various aspects of this disclosure, for monitoring the removal rate of multiple wafers and regulating the recycled slurry returned to the CMP system 100. In some embodiments, one or more blocks of method 800 may be performed by components of the slurry recirculation system 200, the effluent capture device 400, the recovery system 700, the metering controller 750, and / or another component of the CMP system 100.

[0088] Method 800 begins at block 802. At block 804, method 800 relates to obtaining a metrological thickness measurement. In some embodiments, block 802 also relates to determining a wafer removal rate based on the metrological thickness measurement. For example, the wafer removal rate can be determined by comparing the wafer thickness before the CMP process with the wafer thickness after the CMP process. In some embodiments, the metrology controller 750 can be configured to receive the removal rate from another component and / or receive wafer thickness measurements before and after the CMP process from a thickness measuring device and determine the removal rate. The removal rate can also be determined based on the duration of the CMP process. Therefore, the metrology controller 750 can be configured, for example, to receive a measurement of the duration of the CMP process performed on the wafer from another component of the CMP system.

[0089] At block 806, method 800 involves determining whether the wafer removal rate is within specifications. For example, metering controller 750 may determine whether the difference between the removal rate and a specified removal rate is less than a predetermined threshold. In some embodiments, the predetermined threshold may be a difference of about 10%, 7%, 5%, 3%, 2%, 1%, and / or other values ​​therebetween. In response to determining that the removal rate is within specifications, method 800 continues at block 810, wherein metering controller 750 is configured to continue without changing or adjusting the slurry mixture for the next wafer to be processed. However, in response to determining that the removal rate is not within specifications, method 800 continues to block 808, wherein metering controller 750 is configured to adjust the slurry mixture supplied to... Figure 7 The amount of new slurry and / or additives (e.g., pH spikes, abrasives, etc.) in the mixer 730 is then mixed with the finely filtered slurry received in the mixer 730, and then conveyed from the mixer 730 through a slurry return device and to another part of the CMP system (e.g., conveyed to a polishing turntable, for example via slurry delivery system 140) to adjust the removal rate of the next wafer being processed. Method 800 can be repeated for the next wafer processed by the CMP system.

[0090] In some embodiments, additionally or alternatively, the metering controller 750 is configured to regulate the supply to the meter based on the output of one or more sensors 722. Figure 7The metering controller 750 measures the amount of new slurry and / or additives (e.g., pH spikes, abrasives, etc.) supplied to the mixer 730. For example, in some embodiments, sensor 722 may be configured to measure the pH of the finely filtered slurry output from the fine filter 720. In response to determining that the pH of the finely filtered slurry is less than a predetermined value, metering controller 750 may be configured to increase the amount of pH spike additive 742 supplied to the mixer 730. In some embodiments, one or more sensors 722 may be configured to measure the concentration of abrasives included in the finely filtered slurry. In response to determining that the abrasive concentration of the finely filtered slurry is less than a predetermined value, metering controller 750 may be configured to increase the amount of abrasive 744 supplied to the mixer 730. In some embodiments, one or more sensors 722 may be configured to measure the concentration of contaminants (e.g., materials other than slurry and additives) included in the finely filtered slurry. In response to determining that the contaminant concentration of the finely filtered slurry is greater than a predetermined value, metering controller 750 may be configured to increase the amount of new slurry 746 supplied to the mixer 730. In some embodiments, the metering controller 750 may be configured to adjust the amount of new slurry and / or additives (e.g., pH spikes, abrasives, etc.) supplied to the mixer 730 based on measurements taken by the sensor 722, for example, even when the removal rate is within specifications. The new slurry and any additives may then be mixed with the finely filtered slurry received in the mixer 730 and returned from the mixer 730 to another part of the CMP system (e.g., returned to the polishing turntable via a slurry delivery system) to adjust the removal rate of the next wafer being processed.

[0091] By reusing the slurry and adjusting it in response to determining that the removal rate is outside specifications and / or based on sensor 722 measurements, the amount of new slurry and / or additives (e.g., pH spikes, abrasives, etc.) used can be significantly reduced, especially compared to CMP systems that simply discard used slurry without any recycling process. For some CMP processes that use complex and / or expensive slurry chemicals, this can provide significant savings relative to wasteful processes.

[0092] Figure 9 This is an example method 900 for capturing and reusing slurry from CMP system 100, which can be performed by CMP system 100 according to various aspects of this disclosure. In some embodiments, one or more blocks of method 900 may be performed by effluent capture device 400, recovery system 700, metering controller 750 and / or another component of CMP system 100.

[0093] Method 900 begins at block 902. At block 904, method 900 relates to polishing a substrate using the surface of a polishing turntable of a CMP system. In some embodiments, the CMP system may include... Figure 1 or Figure 2 The CMP system 100.

[0094] In block 906, method 900 relates to delivering slurry to the surface of a polishing disc. For example, a slurry delivery system (e.g., slurry delivery system 140) can supply slurry to a polishing disc (e.g., ... Figure 4A and Figure 4B (Polishing turntable 405). In some embodiments, block 906 may be performed before or simultaneously with block 904.

[0095] In box 908, method 900 relates to capturing slurry from a polishing turntable. The slurry can be captured using a discharge system, for example... Figure 5 The emission system 500 and / or Figures 6A to 6C The emission system is 600.

[0096] In box 910, method 900 relates to filtering the captured slurry. A filtration system (e.g.) can be used. Figure 7 The coarse filter 710 and / or fine filter 720 are used to filter the slurry.

[0097] In block 912, method 900 relates to providing filtered slurry to a slurry delivery system. Method 900 ends in block 914.

[0098] In some embodiments, method 900 further includes: capturing slurry flowing from the edge of the polishing disc via a capture tank, causing the captured slurry to flow from the capture tank into a discharge system, receiving the captured slurry from the discharge system at a recovery system, and filtering the captured slurry at the recovery system.

[0099] In some embodiments, the discharge system includes a used slurry inlet, which includes an internal discharge pipe and an external discharge pipe. Method 900 may also include receiving captured slurry from a capture tank using the internal discharge pipe, and receiving a mixture of chemicals and deionized water flowing out of components of the CMP system other than the polishing pad using the external discharge pipe.

[0100] In some embodiments, method 900 further includes guiding the captured slurry to a main discharge pipe when the substrate is started to be processed, and redirecting the captured slurry to a recycling system after a predetermined length of time has elapsed since the start of substrate processing.

[0101] In some embodiments, method 900 further includes performing coarse filtration of the captured slurry, performing fine filtration of the captured slurry, and returning the captured slurry to the slurry delivery system after coarse and fine filtration.

[0102] In some embodiments, method 900 further includes supplying new slurry and additives using a slurry supply device, receiving captured slurry and additives after coarse and fine filtration from the slurry supply device at a mixer, mixing the captured slurry with the new slurry and additives using a mixer, and providing the captured slurry mixed with the new slurry and additives to a slurry delivery system.

[0103] In some embodiments, method 900 further includes adjusting the amount of new slurry supplied from the slurry supply device to the mixer and the amount of additives.

[0104] In some embodiments, method 900 further includes determining a removal rate of the processed substrate, determining that the difference between the removal rate and a specified removal rate is greater than a predetermined threshold, and adjusting the amount of new slurry and / or additives supplied to the mixer in response to determining that the difference between the removal rate and the specified removal rate is greater than the predetermined threshold.

[0105] In some embodiments, method 900 further includes measuring one or more characteristics of the captured slurry output from the fine filter. The amount of new slurry and / or additives supplied to the mixer can be further adjusted based on the measured one or more characteristics.

[0106] Any changes and modifications may be made to the above embodiments, and their elements should be understood in other acceptable examples. All such modifications and changes are intended to be included within the scope of this disclosure. The foregoing description details certain embodiments. However, it should be understood that, however detailed the foregoing may appear in the text, the systems and methods can be practiced in many ways. As noted above, the use of specific terms in describing certain features or aspects of systems and methods should not be construed as implying that the term is redefined herein as limited to any specific characteristic of the system and method that includes the features or aspects of the system and method associated with that term.

[0107] Unless otherwise expressly stated or otherwise understood in the context in which they are used, conditional language, such as “can,” “may,” “may,” or “will,” is generally intended to express that certain embodiments include certain features, elements, and / or steps that are not included in other embodiments. Therefore, such conditional language is not generally intended to imply that features, elements, and / or steps are necessary in any way for one or more embodiments, or that one or more embodiments must include logic for determining whether such features, elements, and / or steps are included in or will be performed in any particular embodiment, with or without user input or prompting.

[0108] Unless otherwise specifically stated, connective language such as the phrases "at least one of X, Y, and Z" or "at least one of X, Y, or Z" should be understood, in context, as generally used to convey that an item, term, etc., can be X, Y, or Z, or a combination thereof. For example, the term "or" is used in its inclusive meaning (rather than its exclusive meaning) such that, when used, for example, to connect a list of elements, the term "or" indicates one, some, or all of the elements in the list. Therefore, such connective language is generally not intended to imply that certain embodiments require at least one of X, at least one of Y, and at least one of Z to each exist.

[0109] The term “a” as used herein should be interpreted inclusively rather than exclusively. For example, unless otherwise specified, the term “a” should not be construed as meaning “exactly one” or “one and only one”; rather, the term “a” means “one or more” or “at least one”, whether used in the claims or elsewhere in the specification, and regardless of whether quantifiers such as “at least one,” “one or more,” or “multiple” are used in the claims or elsewhere in the specification.

[0110] As used herein, the term "comprising" should be interpreted in an inclusive rather than exclusive sense. For example, a general-purpose computer that includes one or more processors should not be construed as excluding other computer components and may include components such as memory, input / output devices, and / or network interfaces.

[0111] While the detailed description above has shown, described, and pointed out novel features applicable to various embodiments, it will be understood that various omissions, substitutions, and changes may be made to the form and details of the illustrated apparatus or process without departing from the spirit of this disclosure. It will be appreciated that some embodiments of the disclosed technology described herein may be embodied in forms that do not provide all the features and benefits set forth herein, as some features may be used or practiced separately from others. The scope of certain aspects of the technology disclosed herein is indicated by the appended claims rather than the foregoing description. All variations within the meaning and scope of equivalents of the claims will be included within their scope.

Claims

1. A chemical mechanical planarization (CMP) system, comprising: A polishing turntable having a surface configured as a polishing substrate; A slurry delivery system configured to deliver slurry to the surface of a polishing turntable; as well as The slurry recirculation system is configured to capture slurry from a polishing disc, filter the captured slurry, and provide the filtered slurry to a slurry delivery system.

2. The system according to claim 1, wherein, The slurry recirculation system includes: An effluent capture device includes a capture tank configured to capture slurry flowing out from the edge of the polishing turntable; Discharge system, configured to receive slurry captured from capture tank; and A recovery system configured to receive and filter the captured slurry from an emission system.

3. The system according to claim 2, wherein, The discharge system includes a used slurry inlet, comprising a first discharge pipe configured to receive captured slurry from the capture tank and a second discharge pipe configured to receive a mixture of chemicals and deionized water flowing from components of the CMP system other than the polishing turntable.

4. The system according to claim 2 or claim 3, wherein, The discharge system includes a valve and a control system configured to direct the captured slurry to a main discharge pipe when substrate processing begins, and to redirect the captured slurry to the recovery system after a predetermined period of time since substrate processing began.

5. The system according to any one of claims 2-4, wherein, The recycling system includes: A coarse filter configured to perform a first filtration on the captured slurry; A fine filter configured to receive slurry captured from a coarse filter and perform a second filtration of the captured slurry; and A slurry return device configured to receive captured slurry from a fine filter and return the captured slurry to the slurry delivery system.

6. The system according to claim 5, wherein, The recycling system also includes: A slurry supply device configured to supply fresh slurry and additives; and A mixer configured to receive captured slurry from the fine filter and new slurry and additives from a slurry supply device, mix the captured slurry with the new slurry and additives, and provide the captured slurry mixed with the new slurry and additives to the slurry return device.

7. The system according to claim 6, wherein, The recycling system also includes: A metering controller configured to regulate the amount of new slurry and additives supplied from the slurry supply device to the mixer.

8. The system according to claim 7, wherein, The metering controller is also configured to: Determine the removal rate of the substrate being processed; The difference between the removal rate and the specified removal rate is greater than a predetermined threshold; and In response to a determination that the difference between the removal rate and the specified removal rate is greater than a predetermined threshold, the amount of new slurry and / or additives supplied to the mixer is adjusted.

9. The system according to claim 7 or claim 8, wherein, The recycling system also includes: One or more sensors configured to measure one or more properties of the captured slurry output from the fine filter. The metering controller is configured to adjust the amount of new slurry and / or additives supplied to the mixer based on one or more measured characteristics.

10. A slurry recirculation system, comprising: An effluent capture device includes a capture tank configured to capture slurry flowing from the edge of a polishing disc in a chemical mechanical planarization (CMP) system; A discharge system configured to receive slurry captured from a capture tank; as well as A recovery system configured to receive and filter slurry captured from an emission system, the recovery system including a slurry return device configured to return the filtered slurry to the slurry delivery system of the CMP system.

11. The device according to claim 10, wherein, The discharge system includes a used slurry inlet, comprising a first discharge pipe configured to receive captured slurry from the capture tank and a second discharge pipe configured to receive a mixture of chemicals and deionized water flowing from components of the CMP system other than the polishing turntable.

12. The device according to claim 10 or claim 11, wherein, The discharge system includes a valve and a control system configured to direct the captured slurry to a main discharge pipe when substrate processing begins, and to redirect the captured slurry to the recovery system after a predetermined period of time since substrate processing began.

13. The device according to any one of claims 10-12, wherein, The recycling system includes: A coarse filter configured to perform a first filtration on the captured slurry; and A fine filter, configured to receive the slurry captured from a coarse filter and perform a second filtration of the captured slurry; and The slurry return device is configured to receive slurry captured from the fine filter.

14. The device according to claim 13, wherein, The recycling system also includes: A slurry supply device configured to supply fresh slurry and additives; and A mixer configured to receive captured slurry from the fine filter and new slurry and additives from a slurry supply device, mix the captured slurry with the new slurry and additives, and provide the captured slurry mixed with the new slurry and additives to the slurry return device.

15. The device according to claim 14, wherein, The recycling system also includes: A metering controller configured to regulate the amount of new slurry and additives supplied from the slurry supply device to the mixer.

16. The device according to claim 15, wherein, The metering controller is also configured to: Determine the removal rate of the substrate being processed; The difference between the removal rate and the specified removal rate is greater than a predetermined threshold; and In response to a determination that the difference between the removal rate and the specified removal rate is greater than a predetermined threshold, the amount of new slurry and / or additives supplied to the mixer is adjusted.

17. The device according to claim 15 or claim 16, wherein, The recycling system also includes: One or more sensors configured to measure one or more properties of the captured slurry output from the fine filter. The metering controller is configured to adjust the amount of new slurry and / or additives supplied to the mixer based on one or more measured characteristics.

18. A method for capturing and reusing slurry from a chemical mechanical planarization (CMP) system, comprising: Surface polishing of substrates using a polishing turntable from a CMP system; The slurry is fed onto the surface of the polishing disc; Slurry is captured from the polishing disc; Filter the captured slurry; as well as The filtered slurry is supplied to the slurry delivery system of the CMP system.

19. The method of claim 18, further comprising: The slurry flowing from the edge of the polishing turntable is captured via a capture tank; The captured slurry flows from the capture tank into the discharge system; The system receives the slurry captured from the discharge system at the recycling system. as well as The captured slurry is filtered at the recycling system.

20. The method according to claim 19, wherein, The discharge system includes a used slurry inlet, which includes a first discharge pipe and a second discharge pipe, and the method further includes: The first discharge pipe is used to receive the captured slurry from the capture tank; and A second discharge pipe is used to receive a mixture of chemicals and deionized water flowing from components of the CMP system other than the polishing turntable.

21. The method according to claim 19 or claim 20, further comprising: When the substrate is being processed, the captured slurry is directed to the main discharge pipe; as well as After a predetermined period of time has elapsed since the substrate was first processed, the captured slurry is redirected to the recycling system.

22. The method according to any one of claims 19-21, further comprising: Perform coarse filtration of the captured slurry; Perform fine filtration of the captured slurry; as well as After coarse and fine filtration, the captured slurry is returned to the slurry delivery system.

23. The method of claim 22, further comprising: Use a slurry supply device to supply new slurry and additives; The slurry captured after the coarse and fine filtrations and the additives from the slurry supply device are received at the mixer. Use a mixer to mix the captured slurry with new slurry and additives; as well as The captured slurry, mixed with new slurry and additives, is supplied to the slurry delivery system.

24. The method of claim 23, further comprising: Adjust the amount of new slurry and additives supplied from the slurry supply device to the mixer.

25. The method of claim 24, further comprising: Determine the removal rate of the substrate being processed; The difference between the removal rate and the specified removal rate is greater than a predetermined threshold. as well as In response to a determination that the difference between the removal rate and the specified removal rate is greater than a predetermined threshold, the amount of new slurry and / or additives supplied to the mixer is adjusted.

26. The method according to claim 24 or claim 25, further comprising: Measure one or more properties of the captured slurry from the fine filtration output of the captured slurry. The amount of new slurry and / or additives supplied to the mixer is further adjusted based on one or more measured characteristics.

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