Substrate carrier and method for polishing a surface of a substrate

Abstract

Embodiments herein generally relate to chemical mechanical polishing (CMP) systems used in the manufacture of electronic devices. In one embodiment, a substrate carrier for polishing a surface of a substrate includes a clasp configured to enclose the substrate during a polishing process. The clasp includes a first surface configured to be in contact with a surface of a polishing pad during the polishing process, a second surface on an opposite side of the clasp from the first surface, and an array of recesses formed on the second surface. The substrate carrier for polishing a surface of a substrate also includes a plurality of bearing pins, wherein each of the plurality of bearing pins includes a contact surface and a body having a length, and at least a portion of the length of each of the plurality of bearing pins is disposed within each of the array of recesses, and the contact surface of each of the plurality of bearing pins is positionable relative to a surface of the recess in which it is disposed during the polishing process.

Description

Technical Field

[0001] Embodiments of the present invention generally relate to chemical mechanical polishing (CMP) systems used in the manufacture of semiconductor devices. Specifically, embodiments herein relate to methods and apparatus for uniformly planarizing the surface of a substrate during a CMP process. Background Technology

[0002] Chemical mechanical polishing (CMP) is commonly used in the fabrication of semiconductor devices to planarize or polish material layers disposed on a substrate surface. In a typical CMP process, the substrate is held in a substrate carrier including a diaphragm by retainers. The diaphragm contacts the back side of the substrate and, in the presence of a polishing slurry, pushes the surface of the material layer on the front side of the substrate toward a rotating polishing pad. Generally, the polishing slurry comprises an aqueous solution of one or more chemical components and nanoscale abrasive particles suspended in the aqueous solution. Material is removed from the surface of the material layer on the substrate through a combination of chemical and mechanical activity provided by the polishing slurry and the abrasive action generated by the relative movement of the substrate and the polishing pad.

[0003] During substrate polishing, polishing shear forces are generated by friction between the substrate and the polishing pad, as well as between the retaining ring positioned around the substrate and the polishing pad. Wear of the retaining ring and the stiffness within the components coupling the substrate carrier to the polishing system cause the retaining ring to tilt relative to the polishing pad surface, thus generating undesirable torques and reaction forces that affect the uniformity of material removal on the substrate surface during polishing. The tilting torque resulting from this tilting can lead to further wear of the retaining ring and contribute to non-uniformity near the substrate edges during CMP processes.

[0004] Therefore, there is a need in this field for products and related methods to solve the above problems. Summary of the Invention

[0005] Embodiments of this disclosure generally relate to chemical mechanical polishing (CMP) systems and methods used in the manufacture of semiconductor devices. In one embodiment, a substrate carrier for polishing a substrate surface includes a retainer configured to surround the substrate during a polishing process. The retainer includes: a first surface configured to contact a surface of a polishing pad during the polishing process; a second surface on a side of the retainer opposite to the first surface; and an array of recesses formed on the second surface. The substrate carrier for polishing a substrate surface also includes a plurality of carrier pins, wherein each of the plurality of carrier pins includes a contact surface and a body having a length, and at least a portion of the length of each of the plurality of carrier pins is disposed within each recess in the array of recesses, and the contact surface of each of the plurality of carrier pins is positionable relative to the surface of the recess in which the carrier pin is disposed during the polishing process.

[0006] In one embodiment, a substrate carrier for polishing the surface of a substrate includes a retaining ring configured to surround the substrate during a polishing process. The retaining ring includes: a first surface configured to contact a surface of a polishing pad during the polishing process; a second surface on a side of the retaining ring opposite to the first surface; and an array of recesses formed on the second surface. The substrate carrier for polishing the surface of the substrate further includes: a plurality of carrier pins, each of the plurality of carrier pins having a contact surface capable of being positioned relative to a surface of a recess therein during the polishing process; and one or more actuator assemblies coupled to one or more of the plurality of carrier pins, the actuator assemblies being configured to adjust the position of the contact surface of one or more of the plurality of carrier pins relative to the surface of a recess therein.

[0007] In one embodiment, a method of polishing a substrate includes positioning portions of carrier pins in each of an array of recesses formed in a first surface of a retainer. The retainer includes a polishing pad contact surface positioned on a side of the retainer opposite to the side of the first surface disposed thereon. The retainer is configured to surround the substrate during a polishing process, and the portions of the carrier pins positioned in the recesses include the contact surface. The method of polishing the substrate further includes rotating a substrate carrier assembly about a central carrier axis and abutting the polishing pad contact surface of the retainer against the surface of a polishing pad, and the contact surface of each carrier pin is positionable relative to the surface of the recess in which the carrier pin is disposed during the polishing process. Attached Figure Description

[0008] To gain a more detailed understanding of the features described above, the present disclosure, which has been briefly summarized above, can be described in more detail with reference to embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the drawings illustrate only exemplary embodiments and should not be construed as limiting their scope, and other equivalent embodiments are permissible.

[0009] Figure 1 This is a schematic side view of a polishing system used according to embodiments disclosed herein.

[0010] Figure 2A-2B According to different embodiments, such as Figure 1 A schematic side view of two substrate carrier assemblies, such as a substrate carrier assembly.

[0011] Figure 3A According to one embodiment Figure 2A A cross-sectional view of the substrate carrier assembly.

[0012] Figure 3B According to one embodiment Figure 2A and Figure 3A Cross-sectional views of different parts of the substrate carrier assembly.

[0013] Figure 3C According to one embodiment Figure 2B A cross-sectional view of the substrate carrier assembly.

[0014] Figure 4A It is locatable according to one or more embodiments described herein. Figure 2A-2B or Figures 3A-3C A schematic isometric view of the load pin ring within a portion of the substrate carrier assembly.

[0015] Figure 4B It is locatable according to one or more embodiments described herein. Figure 2A-2B or Figures 3A-3C A schematic isometric view of the load pin element within a portion of the substrate carrier assembly.

[0016] Figure 5 According to one or more embodiments Figure 2A-2B A cross-sectional view of a portion of the carrier ring assembly.

[0017] Figures 6A-6C The illustration shows the application of one or more embodiments on Figure 5 A cross-sectional view of the forces on a portion of the carrier ring assembly shown.

[0018] To facilitate understanding, the same reference numerals are used where possible to indicate common elements in the figures. It is contemplated that elements and features of one embodiment can be advantageously combined in other embodiments without further description. Detailed Implementation

[0019] The embodiments described herein generally relate to chemical mechanical polishing (CMP) systems used in the manufacture of electronic devices. Specifically, the embodiments described herein relate to substrate carriers and methods for CMP treatment of semiconductor substrates.

[0020] The embodiments described herein provide configurations for controlling the tilting torque M generated during a CMP process by the interaction between a retainer surrounding a substrate and a polishing pad. G ( Figure 1The substrate carrier. In some embodiments, the effect of the generated tilting moment is controlled by positioning a support pin, or simply a load pin, which has a desired shape and orientation at a desired location within the retainer to counteract the tilting moment M generated by undesirable stiffness in the elements coupling the substrate carrier to the polishing system (e.g., a gimbal assembly) as the substrate carrier rotates about its central axis and translates across the polishing pad via various hardware components. G The components that couple the substrate carrier to the polishing system generate a retaining reaction force in response to the stiffness or resistance of torsional motion. This retaining reaction force acts at a distance from these coupled components, generating a tilting moment M. G Therefore, the tilting moment M G This is typically due to the resistance of the substrate carrier coupled to the polishing system to the changing position of the retainer relative to the polishing pad during the continuous rotation and movement of the retainer and polishing pad relative to each other in the CMP polishing process. Therefore, the tilting torque experienced by the carrier retainer 502 during processing prevents the lower surface of the retainer (i.e., the polishing pad contact surface) from uniformly contacting the surface of the polishing pad. This prevents the retainer, positioned near the edge of the substrate, from controlling and / or uniformly providing pressure distribution on the surface of the polishing pad near the edge of the substrate 105 during polishing, especially in the radial direction relative to the center of the substrate. The pressure applied to the surface of the polishing pad by the retainer during processing is used to reduce various edge effects (e.g., "check mark" effect or "knife-edge" effect) naturally experienced at the edge of the substrate during the polishing process.

[0021] Additionally, the substrate, substrate clamping elements, or other internal components of the substrate carrier frequently shift beneath the substrate carrier and impact the radially inner surface of the retainer. Contact between the substrate and / or substrate carrier and the inner surface of the retainer can generate lateral impact forces applied to the radially inner surface of the retainer, which may undesirably affect the load and / or torque experienced by the retainer during polishing, and thus produce polishing inhomogeneities, which are also addressed by one or more embodiments of the disclosure provided herein.

[0022] As discussed further below, the reaction force experienced by the retaining ring, and consequently the reaction force experienced by the substrate, can be controlled by controlling at least the position of the load pin within the retaining ring and thereby controlling the interaction of the load pin. In some embodiments, one or more actuator assemblies are used to position the load pin within the retaining ring, thereby adjusting the contact position of the load pin relative to the polishing pad contact surface of the retaining ring. Adjusting the contact position increases or decreases the generated torque to counteract the tilting torque M experienced by the retaining ring, at least due to the shear and impact-related forces applied to the retaining ring during the polishing process. G It is also believed that as the buckle wears down, the tilting moment M...G Over time, this often leads to polishing uniformity issues within or between substrates, particularly at the radially outward edges of the substrate. In some embodiments, the tilting torque M can be controlled during processing by actively adjusting the position of the load pin within the retainer. G Or maintain tilting moment M G It is constant and can keep the pressure distribution on the substrate, especially the pressure distribution on the radially outward edge of the substrate, uniform.

[0023] Figure 1 This is a schematic side view of a polishing system 100 used according to embodiments disclosed herein. The polishing system 100 includes a polishing station 102 and a system controller 107. The system controller 107 typically controls the activities and operating parameters of automated components found in the polishing system 100. Generally, movement of a substrate through various parts of the polishing system 100, such as through polishing station 102, is performed using commands sent by the system controller 107. The system controller 107 is a general-purpose computer for controlling one or more components found in the polishing system 100. The system controller 107 is generally designed to facilitate control and automation of one or more processing sequences among those disclosed herein and typically includes a central processing unit (CPU) (not shown), memory (not shown), and support circuitry (or I / O) (not shown). Software instructions and data may be encoded and stored in memory (e.g., a non-transient computer-readable medium) for instructing the CPU. A program (or computer instructions) readable by the processing unit within the system controller 107 determines which tasks can be performed in the polishing system 100. For example, a non-transient computer-readable medium includes a program configured to perform one or more of the methods described herein when executed by a processing unit. Preferably, the program includes code for performing tasks related to monitoring, performing, and controlling the movement, support, and / or positioning of the substrate, as well as various process formulation tasks and various polishing station 102 process formulation steps performed therein.

[0024] As shown, polishing station 102 includes a carrier assembly 104, a worktable 106, a polishing pad 108 mounted on and fixed to the worktable 106, a pad adjuster assembly 110 for cleaning and / or restoring the polishing pad, and a fluid delivery arm 112 for dispensing polishing fluid onto the polishing pad 108. A gimbal assembly 191 couples the carrier assembly 104 to various hardware components (not shown) configured to allow the carrier assembly 104 to rotate about axis A and simultaneously translate across the surface of the polishing pad 108 during the polishing process. The carrier assembly 104 typically includes a retaining ring 109, a carrier member 204, a housing member 202, and a first diaphragm 214, all of which are described in more detail below. Here, the worktable 106 is positioned above a base plate 114 and surrounded by a worktable shield 120 (both shown in cross-section), which together define a drain basin 116. The drain basin 116 is used to collect the fluid that rotates radially outward from the worktable 106 and to discharge the fluid through the discharge port 118 which is in fluid communication with the drain basin 116.

[0025] The pad adjuster assembly 110 is used to abrade the surface of the polishing pad 108 by pushing the adjuster disk 124 (e.g., a diamond dip disk) against the polishing pad 108 to clean and / or restore the polishing pad 108. The pad adjustment operation can be performed between polishing substrates (i.e., off-site adjustment), simultaneously with polishing substrates (i.e., in-situ adjustment), or both.

[0026] Here, the pad adjuster assembly 110 includes a first actuator 126 disposed on a base plate 114, an adjuster arm 128 coupled to the first actuator 126, and a mounting plate 130 having an adjuster disk 124 fixedly coupled thereto. A first end of the adjuster arm 128 is coupled to the first actuator 126, and the mounting plate 130 is coupled to a second end of the adjuster arm 128 remote from the first end. The first actuator 126 is used to sweep the adjuster arm 128 about axis C and thus sweep the adjuster disk 124 such that when the polishing pad 108 rotates below the adjuster disk 124, the adjuster disk 124 oscillates between the inner radius and the outer radius of the polishing pad 108. In some embodiments, the pad adjuster assembly 110 further includes a second actuator 132 disposed at and coupled to the second end of the adjuster arm 128. The second actuator 132 is used to rotate the adjuster disk 124 about axis D. Typically, a shaft 134 disposed between the mounting plate 130 and the second actuator 132 is used to couple the mounting plate 130 to the second actuator 132.

[0027] In some embodiments, as the stage 106, and therefore the polishing pad 108, rotates about the stage axis B below the rotating substrate carrier assembly 104, the rotating substrate carrier assembly 104 sweeps back and forth from the inner radius to the outer radius of the stage 106. Polishing slurry is delivered to the polishing pad 108 using a fluid delivery arm 112 positioned above the polishing pad 108, and further delivered to the polishing interface between the polishing pad 108 and the substrate 105 by the rotation of the polishing pad 108 about the stage axis B. Typically, the fluid delivery arm 112 further includes a delivery extension member and a plurality of nozzles. The plurality of nozzles are used to deliver polishing slurry or a relatively high-pressure stream of cleaning fluid (e.g., deionized water) to the polishing pad 108.

[0028] The substrate carrier assembly 104 includes a mounting surface on which the substrate 105 is positioned and held during processing. During substrate processing, the substrate carrier assembly 104 surrounds the substrate 105 and applies a downward force to the substrate 105 to enable the polishing process and prevent the substrate 105 from sliding out from under the substrate carrier assembly 104. The substrate 105 is typically held in place by the substrate carrier assembly 104. The substrate carrier assembly 104 rotates about a carrier axis A while pushing the substrate 105 against a polishing pad 108. As described above, the substrate carrier assembly 104 also translates over the top surface of the polishing pad with an oscillating motion.

[0029] Figure 2A-2B This is a schematic side view of two different substrate carrier assemblies 104a and 104b according to different embodiments, which can be used as... Figure 1 The substrate carrier assembly 104 is shown. It is contemplated in the embodiments herein that the elements of each of the substrate carrier assemblies 104a or 104b can be combined with and / or replace elements of the other substrate carrier assembly 104a or 104b. Generally, each of the substrate carrier assemblies 104a-b is characterized by: a housing member 202, a carrier member 204, a retaining ring 109 coupled to the carrier member 204, a support plate 212 disposed radially inside the carrier member 204 and the retaining ring 109, and a first diaphragm 214 (such as a substrate clamping diaphragm) disposed below the support plate 212 to provide a mounting surface for the substrate 105. For the purpose of description... Figure 2A-2B Unless otherwise stated, the term radially outward refers to the reference carrier axis A, i.e., during polishing ( Figure 1This is used for the rotation axis of each of the substrate carrier assemblies 104a-b during the process. In some embodiments, the retaining ring 109 may include two or more elements for improving the mechanical stability and robustness of the hardware and / or improving the polishing process results. Although the retaining ring 109 is generally shown herein as comprising a single solid element, this configuration is not intended to limit the scope of the disclosure provided herein, as more complex multi-element retaining rings may alternatively be used with any of the embodiments disclosed herein.

[0030] As mentioned above, Figure 2A-2B Each of the substrate carrier assemblies 104a-b is used to apply a downward force to the back (non-active) surface of the substrate 105. The downward force applied by the substrate carrier assembly 104a or 104b is used to push the substrate 105 against the surface of the polishing pad 108. Each of the substrate carrier assemblies 104a-b is configured to hold the substrate 105 under the substrate carrier assembly 104a-b throughout the polishing process.

[0031] In some cases, the substrate 105 and / or the entire support plate 212 and the first diaphragm 214 are movable within the carrier volume 252. The carrier volume 252 is defined as the volume below the housing member 202 and the carrier member 204 of the carrier assembly 104 and above the surface of the polishing pad 108. The majority of the carrier volume 252 is occupied by the support plate 212 and the first diaphragm 214.

[0032] The housing member 202 is a support member and the uppermost portion of each of the substrate carrier assemblies 104a-b. The upper surface of the housing member 202 is connected to a mating flange (not shown) coupled to a gimbal assembly 191 (not shown), which allows the substrate and substrate carrier assemblies 104a, 104b to be positioned substantially parallel to the polished surface of the polishing pad during processing. In some embodiments, the housing member 202 includes a centering member 222 disposed on the bottom surface of the housing member 202 and centered on the carrier axis A. The centering member 222 further includes a cover 224. The cover 224 is configured to surround a portion of a downwardly extending extension of the centering member 222. The cover 224 is configured to reduce friction between the centering member and a recess within the carrier member 204. The carrier member 204 is configured to surround and be coupled to the housing member 202. The carrier member 204 is configured to surround each of the support plate 212 and the first diaphragm 214. The carrier member 204 covers each of the support plate 212 and the first diaphragm 214 and is disposed between the support plate 212 and the housing member 202. The carrier member 204 includes an outer portion that extends downward and surrounds the outer diameter of the support plate 212 and the first diaphragm 214.

[0033] As described herein, a first flexible member 218 is used to attach the support plate 212 and the first diaphragm 214 to the carrier assembly 204. The first flexible member 218 is an annular bend and allows the substrate 105, the support plate 212, and the first diaphragm 214 to move relative to the carrier assembly 204 in both vertical and horizontal directions during substrate processing (where the vertical direction is parallel to the carrier axis A, and the horizontal direction is parallel to the polishing pad 108). Figure 1 The first flexible member 218 can be bent or deformed to allow vertical movement of the support plate 212 relative to the carrier member 204. The first flexible member 218 allows controlled movement of the support plate 212 while supporting the load of the support plate 212.

[0034] The support plate 212, carrier member 204, and first flexible member 218 together define a first volume 230 between the support plate 212 and the carrier member 204. Typically, the first volume 230 and the plurality of channels 226 formed in the first diaphragm 214 are individually pressurized during polishing to apply a downward force on the substrate 105 as the substrate carrier assemblies 104a, 104b rotate about the carrier axis A, thereby pushing the substrate 105 against the polishing pad 108. Figure 1 On. One or more channels 226 formed in the first diaphragm 214 are annular and centered on the carrier axis A. For example, in Figure 2A-2B In this configuration, a first channel 227 is disposed at the rotation center of the substrate carrier assembly 104a-b, such that the carrier axis A is disposed through the first channel 227, and a plurality of annular channels 226 (eight shown) are disposed around the first channel 227 and radially spaced outward from the carrier axis A. In some embodiments, approximately five to approximately fifteen channels 226 may be included, such as approximately six to approximately twelve channels 226, such as approximately seven to approximately ten channels 226. Each channel 226 is in fluid communication with a gas channel formed within the support plate 212. The channels 226 are used to apply positive or negative gas pressure to the back surface of the substrate 105. A first diaphragm 214 is formed of a soft and / or flexible material, such as an elastic material (e.g., silicone material), which allows the first diaphragm 214 to deflect as the pressure within each of the annular channels 226 increases or decreases. Each channel 226 in the channel 226 may have different or the same gas pressure to achieve different levels of vacuum force across the radius of the substrate 105.

[0035] Before and after polishing, a vacuum is applied to the first volume 230, causing the first diaphragm 214 to deflect upwards, creating a low-pressure pocket between the first diaphragm 214 and the substrate 105, thereby lifting the support plate 212 and the clamped substrate 105 from the surface of the polishing pad. The substrate can be “clamped” to the first diaphragm 214 by applying vacuum pressure to one or more of the plurality of channels 226 formed in the first diaphragm 214. The first diaphragm 214 is coupled to the bottom of the support plate 212. Therefore, the first diaphragm 214 is also configured to clamp the surface of the substrate 105 by applying a vacuum to one or more of the plurality of channels 226 formed in the first diaphragm 214. The first diaphragm 214 extends across substantially the entire bottom surface of the support plate 212.

[0036] A second flexible support 220 is disposed between the carrier member 204 and the housing member 202. The second flexible support 220 is an annular support coupling the carrier member 204 to the housing member 202. A second volume 232 is defined between the carrier member 204 and the housing member 202. The second flexible support 220 forms a seal between the carrier member 204 and the housing member 202 to allow adjustment of the pressure formed within the second volume 232 relative to the surrounding environment, and thereby allows the carrier member 204 to shift relative to the housing member 202 due to the extension or retraction of the flexible support 220. Therefore, the pressure formed within the second volume 232 can be used to influence the vertical deflection of the carrier member 204 relative to the housing member 202, and in some cases, as described below, relative to… Figure 2B and Figure 3C The downward force can be applied to the polishing pad separately by the carrier ring assembly 206 coupled to the carrier member 204.

[0037] In some embodiments, such as Figure 2A and Figure 3A As shown, the retaining ring 109 is disposed below the outer portion of the carrier member 204. In some embodiments of the substrate carrier assembly 104 (such as substrate carrier assembly 104a ( Figure 2A The substrate carrier assembly includes an actuator assembly 601, a retaining ring 109, a load pin ring 504, and a plurality of load pins 338 coupled to a portion of the load pin ring 504.

[0038] Figure 3A According to one embodiment Figure 2A A cross-sectional view of a portion of the substrate carrier assembly 104a. More specifically, Figure 3AThis is an expanded cross-sectional view of the retaining ring 109 coupled to the carrier member 204 via the actuator assembly 601. The retaining ring 109 includes a carrier retaining ring 502, which includes an array of upper recesses 505 configured to receive a load pin 338 of the actuator assembly 601. In some embodiments, each upper recess 505 is a blind hole or blind groove having a surface configured to contact a portion of the load pin 338 (e.g., ...). Figure 3A (Vertical surface in the middle). Generally, the actuator assembly 601 includes a plurality of load pins 338, one or more actuators 401, and one or more springs 602. One or more springs 602 disposed between a portion of the carrier member 204 and a portion of the load pin 338 are configured to counteract the load applied by the one or more actuators 401, such that at any moment when the carrier assembly 104a rotates about axis A during a polishing process and simultaneously translates across the surface of the polishing pad 108, the position of the contact portion of the load pin 338 is positioned at a desired height or position within the upper recess 505. In some embodiments, the contact shoulder 501 of the load pin 338 has a greater thickness than the remainder of the body 339 of the load pin 338, such that the contact shoulder 501 can be used as a contact point 507 between the load pin 338 and the upper recess 505 formed in the carrier retainer 502 ( Figure 5-6C This will be discussed further below. In one example, such as Figure 3A and Figure 3C As shown, due to the presence of the contact shoulder 501, each of the plurality of load pins 338 has a thickness or horizontal width at the end of the length 340 of the body 339 that is greater than the horizontal width of the rest of the length of the load pin 338. In one embodiment that can be combined with other embodiments disclosed herein, the spring 602 is made of stainless steel.

[0039] In some embodiments, the system controller 107 is configured to adjust the amount of force applied to the load pins 338 and the spring 602 by one or more of the actuators 401 to adjust the position of one or more load pins 338 within their respective upper recesses 505 at any time to compensate for the tilting torque applied to the carrier retainer 502. In one example, the system controller is configured to cause one or more actuators 401 to move toward a load pin ring 504 comprising a plurality of load pins 338 ( Figure 4A The load pin ring 504 and load pin 338 are subjected to a desired amount of force by the spring 602 to adjust the position of the load pin ring 504 and load pin 338 relative to the upper recess 505 formed in the carrier retainer 502. In another example, the system controller 107 is configured to cause the actuator 401 to apply force to the load pin element 511 including the load pin 338. Figure 4BThe load pin 338 and spring 602 apply a desired amount of force to adjust the position of the contact portion of the load pin 338 relative to the upper recess 505 formed in the carrier retainer 502.

[0040] In one embodiment, one or more force actuators 401 may include a pneumatic actuation device configured to receive gas delivered at a desired pressure through ports (not shown) formed in the carrier member 204 and the housing member 202 to deliver a desired amount of force to the load pin 338 and the spring 602. In another embodiment, one or more actuators 401 may include an electromechanical braking device configured to receive and receive electrical power from and through a rotating electrical feedthrough (not shown) formed in the housing member 202. The ratio of the number of actuators in the actuator assembly 601 to the number of load pins 338 is any suitable ratio to allow adequate control of the load pins 338, such as about 1:3 to about 1:1. In some embodiments, each of the actuators in the actuator assembly 601 is coupled to one or more of the plurality of load pins 338 and configured to actuate the one or more load pins 338 vertically. Figure 5 and Figures 6A-6C As shown, power supply 280 can be coupled to one or more actuators in actuator assembly 601. One or more force actuators 401 and spring 602 are operable to raise or lower load pin 338 relative to carrier retainer 502 by about 0.001 inches to about 1.25 inches, for example about 0.005 inches to about 1 inch, or between 0.01 inches and 0.5 inches, or even between 0.1 inches and 0.25 inches.

[0041] In some embodiments that can be combined with other embodiments described herein, such as Figure 3B As shown, the load application element 522 is generally disposed between the carrier buckle 502 and the carrier member 204. Figure 3BThe cross-sectional view shown includes a portion of the carrier assembly 104 disposed between adjacent load pins 338, and therefore the load application element 522 may include a plurality of regularly spaced sections distributed between the load pins 338, such that a relatively uniform downward force can be applied by the load application element 522 to the carrier retainer 502 and the polishing pad 108. The load application element 522 may include an air bladder, bellows, or other expandable element sealed at one end to the carrier assembly 204. The amount of downward force that the carrier retainer 502 can apply to the surface of the polishing pad 108 during processing can be adjusted by inflating or deflating the internal region 523 of the load application element 522 using a gas source 524, and also by adjusting the relative position of the carrier retainer 502 with respect to the load pins 338. The downward force applied by the load applying element 522 is adjusted by using system controller 107. System controller 107 controls the air pressure formed in the internal region 523 by using one or more pneumatic components (e.g., valves, pressure regulators, etc.), which are capable of adjusting the pressure of the gas delivered through ports (not shown) formed in the carrier member 204 and the housing member 202.

[0042] In some embodiments of the substrate carrier assembly 104, the sensor assembly 531 ( Figure 3AA sensor assembly 531 is provided within actuator assembly 601 to detect and / or measure the relative height of the portion of load pin 338 to retainer 109. In one embodiment, sensor assembly 531 includes retainer position sensor 532 and load pin position sensor 533, which are used individually or in combination to detect and / or measure the relative height of the portion of load pin 338 to retainer 109. Retainer position sensor 532 is configured to measure the distance between the surface of carrier member 204 and carrier retainer 502. Load pin position sensor 533 is configured to measure the distance between the portion of carrier member 204 and load pin 338. In one embodiment, once the relative height of load pin 338 is determined by comparing the signals provided by sensors 532, 533, the position of load pin 338 can be adjusted accordingly using force actuator 401, spring 602, and commands sent from system controller 107. In some embodiments, by using a calibration process, the average distance between the carrier member 204 and the partial carrier retainer 502 can be predetermined, such that the system controller 107 requires only a single input from the load pin position sensor 533 to adjust the position of the load pin 338 relative to the carrier retainer 502. The retainer position sensor 532 and the load pin position sensor 533 may include devices configured to measure the relative distance between components or surfaces using optical techniques (e.g., laser sensors, ultrasonic sensors, or other non-contact displacement or distance measurement sensors) or mechanical techniques (e.g., LVDT, line-activated encoder sensors).

[0043] In some embodiments, such as Figure 4A As shown, multiple load pins 338 are coupled together to form a load pin ring 504. The load pins 338 within the load pin ring 504 are used to receive and distribute the reaction force generated by the varying tilting torque received by each load pin 338 as the carrier assembly 104a rotates about axis A and simultaneously translates on the surface of the polishing pad 108 during the polishing process. (See bottom isometric view of the load pin ring 504.) Figure 4AAs shown, the load pin ring 504 includes a plurality of load pins 338 (e.g., nine load pins 338 are shown), which are oriented in a circular array and thus configured to be disposed within the circular array of an upper recess 505 formed within the carrier retainer 502. The load pin ring 504 includes a body portion 509 that couples each of the plurality of load pins 338 together. The load pin ring 504 may be formed of a solid structural material such as metal (e.g., SST), which may be cast or machined to form a solid structural member. In some embodiments, the plurality of load pins 338 of the load pin ring 504 are equidistantly spaced within the carrier retainer 502. In some embodiments, the contact shoulder 501 of the load pin 338 has a greater thickness than the body 339 of the load pin 338 and serves as a contact point 507 between the load pin 338 and the carrier retainer 502. Figure 5 -6), which will be discussed further below.

[0044] However, in some embodiments, each of the plurality of load pins 338 may be individually mounted and positioned within a portion of the carrier member 204, and thus in this configuration, it will be possible to position the contact portion of each load pin 338 relative to the upper recess 505 formed within the retaining ring 109 at different heights by using an actuator 401 directly or indirectly coupled to the respective load pin 338. In one configuration, the load pin element 511 may include load pins 338 coupled to a base element 508. The base element 508 is mounted on the upper end of the load pin 338 and may be used to provide an anchor point or mounting surface for the load pin 338. (See bottom isometric view as load pin element 511) Figure 4B As shown, the load pin elements 511 can each be individually disposed within a circular array of upper recesses 505 formed within the carrier retainer 502. The load pin elements 511 can be formed from a solid structural material such as metal (e.g., SST), which can be cast or machined to form a solid structural member.

[0045] Generally, in the configuration of the load pin element 511 or load pin ring 504, the number and spacing of the load pins 338 can be selected to optimize the even distribution of the reaction force experienced by the retainer, while reducing cost and complexity of the substrate carrier assembly 104. Therefore, in some embodiments, the number of load pins 338 used in the substrate carrier assembly 104 may include, for example, four or more, six or more, eight or more, twelve or more, or any suitable value.

[0046] In one embodiment of the load pin 338, the body 339 of each load pin 338 is generally I-shaped and has a generally uniform thickness. In another embodiment, the body 339 of each load pin 338 is generally T-shaped, with a greater horizontal width at the end of the load pin 338 that does not contact the carrier retaining ring 502 for coupling the load pin 338 to the load pin ring 504. In yet another embodiment, the body 339 of each load pin 338 is generally L-shaped, with a greater horizontal width at the end of the load pin 338 configured to contact the carrier retaining ring 502. The body 339 has a length 340 and a cross-sectional area measured in a direction perpendicular to the length 340. Generally, for a particular material (e.g., 316 SST), both the length 340 and the cross-sectional area are dimensioned such that the load pin will not break or fracture during normal use. In one example, the length 340 is between 12 mm and 60 mm, such as between 16 mm and 50 mm, or even between 18 mm and 40 mm. In some embodiments, during processing, the amount of overlap between the portion of the body 339 disposed within the upper recess 505 formed in the carrier retainer 502 and the upper recess 505 may be between 10% and 95% of the length 340 of the body, such as between 40% and 90% of the length 340.

[0047] Figure 3C According to one embodiment Figure 2B A cross-sectional view of a portion of the substrate carrier assembly. More specifically, Figure 3CThis is an extended cross-sectional view of the retaining ring 109 and the carrier ring assembly 206, both of which are coupled to the carrier member 204. According to one embodiment that can be combined with other embodiments disclosed herein, the retaining ring 109 includes a carrier retaining ring 502 having a plurality of upper recesses 505 configured to receive at least a portion of the load pin 338, wherein the carrier retaining ring 502 includes protrusions 503 on its radially outer surface. The protrusions 503 may be annular protrusions extending around the entire carrier retaining ring 502, or there may be a discrete number of protrusions 503 extending from the radially outer surface of the carrier retaining ring 502, such as two or more, five or more, ten or more protrusions 503. The protrusions 503 prevent unwanted liquids, particles, or other contaminants from being trapped in the space adjacent to the carrier retaining ring 502. Each of the plurality of load pins 338 is disposed in each of the plurality of upper recesses 505 of the carrier retainer 502. In some embodiments, as described above, the plurality of load pins 338 are coupled together such that they form a load pin ring 504. In some embodiments, each of the plurality of load pins 338 may be individually mounted and positioned within a portion of the carrier member 204, and thus may be configured similarly to the load pin element 511 as described above. In some embodiments, the plurality of load pins 338 are equidistantly spaced within the carrier retainer 502.

[0048] In some embodiments of the substrate carrier assembly 104b, which can be combined with other embodiments described herein, a load application element (such as a U-shaped airbag 512) is disposed between the carrier retainer 502 and the carrier member 204. The U-shaped airbag 512 can be sealed at one end coupled to the carrier retainer 502 using a clamp 513, and at the opposite ends by clamping a portion of the U-shaped airbag 512 to a portion of the carrier member 204. The internal region 512A of the U-shaped airbag 512 can be inflated or deflated to adjust the amount of downward force that the carrier retainer 502 can apply to the surface of the polishing pad 108 during processing, and also to adjust the relative position of the carrier retainer 502 relative to the load pin 338. The downward force applied by the U-shaped airbag 512 is adjusted by controlling the pressure of the gas supplied via ports (not shown) formed in the carrier member 204, the housing member 202, and the U-shaped plate 514, which forms the gas pressure in the internal region 512A.

[0049] In some embodiments of the substrate carrier assembly 104b, the pressure within the second volume 232 can be formed and controlled using a gas source and system controller 107, such that an adjustable downward force can also be generated solely on the polishing pad 108 by the carrier ring assembly 206 coupled to the carrier member 204. The pressure formed within the second volume 232 will affect the vertical deflection of the carrier member 204 relative to the housing member 202, and thus allow the carrier ring assembly 206 to apply a downward force to the polishing pad 108 solely relative to the carrier retainer 502.

[0050] In some embodiments of the substrate carrier assembly 104, the contact portion of the load pin 338 (e.g., contact shoulder 501) is intended to be fixed relative to the carrier member 204, but is configured to be positioned at a desired location relative to the upper recess 505 of the carrier retainer 502. In this configuration, the actuator assembly 601 is not required, and the body 509 of the load pin ring 504 or the base element 508 of the load pin element 511 can be mounted or coupled to a portion of the carrier member 204, thus allowing the load pin 338 to remain fixed relative to the carrier member 204 during processing. Therefore, by modeling and / or pre-testing, the vertical length of the load pin 338 (e.g., length 340) (e.g., the insertion depth within the upper recess 505) can be determined such that the load pin 338 is positioned at a desired average height relative to the depth within the upper recess 505 and relative to the surface of the polishing pad 108, to desirously counteract the tilting torque generated during processing.

[0051] Figure 5 and Figures 6A-6C yes Figure 2A-2B , Figure 3A and Figure 3C A schematic cross-sectional view of a portion of the substrate carrier assembly 104, and intended to illustrate one or more embodiments of the disclosure provided herein for causing the tilting torque M generated during the polishing process. G To minimize the impact of the effect. Figure 5 This is a schematic representation of various elements of the polishing station 102 used in one or more embodiments of the disclosure provided herein. While not intended to limit the scope of the disclosure provided herein, Figure 5 and Figures 6A-6C The system includes a substrate carrier assembly 104, which includes an actuator component 601 configured to partially position a load pin 338 (e.g., contact shoulder 501) relative to an upper recess 505. As discussed above, the force actuator 401 may include a pneumatic, piezoelectric, electromechanical, or any other suitable device capable of positioning the load pin 338 relative to the carrier member 204 at a desired height via a compression spring 602.

[0052] During processing, the carrier retainer 502 is pushed against the surface of the polishing pad 108 using a load generating element (such as a U-shaped airbag 512 or a load applying element 522), and the substrate 105, which is positioned adjacent to the carrier retainer 502, is pushed against the surface of the polishing pad using a first diaphragm 214. During processing, a polishing shear force 802 is generated at the lower surface of the carrier retainer 502 due to the frictional force generated between the carrier retainer 502 and the surface of the polishing pad. Figure 6A Therefore, by adjusting the position of the contact portion (e.g., the contact shoulder 501) of the load pin 338 within the upper recess 505, a relative reaction force 801 is generated due to the contact between the portion of the load pin 338 and the portion of the upper recess 505. Figure 6A This generates a relative torque or reaction torque that counteracts the tilting torque, allowing the magnitude of the tilting torque to be eliminated, controlled, kept constant, or at least minimized during processing. Because the carrier retainer 502 is positioned near the edge of the substrate 105 and configured to reduce the high contact forces typically experienced at the edges of the substrate during processing (e.g., the "check mark" effect or "knife edge" effect), the pressure distribution on the substrate 105 during polishing (especially in the radial direction relative to the center of the substrate 105) can be made more uniform.

[0053] Figures 6A-6C The application of one or more embodiments is shown. Figure 5 The force on a portion of the retaining ring 109. As discussed above, during the CMP polishing process, due to the resistance of the elements coupling the substrate carrier assembly 104 to the polishing system to the changing position of the retaining ring relative to the polishing pad as the retaining ring and polishing pad rotate and move relative to each other, a tilting moment M is formed. G Furthermore, during processing, the substrate 105, the first diaphragm 214, or other internal components of the substrate carrier assembly 104a-b frequently shift slightly beneath the carrier and impact the inner surface of the carrier retainer 502 at the first contact point, resulting in a lateral impact force applied to the radially inner surface of the carrier retainer 502. A polishing shear force 802 is also applied to the carrier retainer 502 as the retainer and polishing pad move relative to each other during the CMP polishing process. These lateral forces applied to the radially inner surface of the carrier retainer 502 result in a reaction force 801 acting on the carrier retainer 502 through the contact shoulder 501 of the load pin 338. Adjusting the vertical position of the contact point 507 between the load pin 338 and the carrier retainer 502, i.e., adjusting the position of the resultant force 801, increases or decreases the generated torque to counteract the tilting torque experienced by the carrier retainer 502 during the polishing process.

[0054] In other words, by adjusting the position of the load pin 338, the offset distance 803, or distance, or height 803 between the lower surface of the carrier retainer 502 on which shear force 802 is generated and the reaction force 801 can be increased or decreased. If... Figure 6B Compared to Figure 6A As shown, reducing the offset distance 803 reduces the tilting moment of the resulting carrier retainer 502. The counteracting tilting moment generated by the resultant force 801 is proportional to the offset distance 803 and the polishing shear force 802 applied to the lower surface of the substrate carrier retainer 502. Figure 6C The increased offset distance 803 shown results in an increase in the counteracting tilting moment of the carrier retainer 502. If as... Figure 6C As shown, further reducing the offset distance 803 increases the anti-tilt moment of the resulting carrier retainer 502. The anti-tilt moment of the carrier retainer 502 can be controlled by using the actuator assembly 601 to vertically actuate the load pin 338 to increase the offset distance 803 when the tilt moment is undesirably large and to decrease it when the tilt moment is small, by monitoring the offset distance 803 with a sensor and / or system controller 107. In some embodiments, it may be desirable to maintain a constant anti-tilt moment regardless of wear on other components of the carrier retainer 502, polishing pad 108, or retainer 109.

[0055] Embodiments of this disclosure allow for improved control over the forces experienced by the retaining ring in the polishing module. This improved control is associated with improved pressure distribution control over the surface of substrate 105 and results in improved substrate polishing uniformity.

[0056] While the foregoing relates to embodiments of this disclosure, other and further embodiments of this disclosure may be devised without departing from the basic scope of this disclosure, the scope of which is defined by the appended claims.

Claims

1. A substrate carrier for polishing the surface of a substrate, characterized in that... include: A retaining ring, configured to surround a substrate during a polishing process, the retaining ring comprising: A first surface, the first surface being configured to contact the surface of the polishing pad during the polishing process; The second surface is on the side of the clasp opposite to the first surface; and An array of recesses formed in the second surface; and Multiple bearing pins, among which Each of the plurality of carrier pins includes a contact shoulder and a body having a length. At least a portion of the body of each of the plurality of support pins is disposed within each recess in the array of recesses, and The contact shoulder of each of the plurality of carrier pins can be positioned relative to the surface of the recess in which the carrier pin is disposed during the polishing process.

2. The substrate carrier of claim 1, wherein the substrate carrier further comprises an actuator assembly coupled to one or more of the plurality of carrier pins, the actuator assembly being configured to adjust the position of the contact shoulder of one or more of the plurality of carrier pins relative to the surface of the recess in which the carrier pin is disposed.

3. The substrate carrier of claim 2, wherein the substrate carrier further comprises: Carrier components, The actuator assembly further includes: A return spring, wherein the return spring is disposed between a portion of the carrier member and a portion of each of the plurality of carrier pins; and A force actuator coupled to the carrier member and configured to compress or decompress the return spring when the position of the contact shoulder is adjusted relative to the surface of the recess.

4. The substrate carrier of claim 1, wherein the substrate carrier further comprises one or more actuator assemblies coupled to one or more of the plurality of carrier pins, the one or more actuator assemblies being configured to adjust the position of the contact shoulder of one or more of the plurality of carrier pins relative to the surface of the recess in which the carrier pin is disposed, wherein the ratio of the number of actuator assemblies to the number of carrier pins is between 1:3 and 1:

1.

5. The substrate carrier of claim 1, wherein the substrate carrier further comprises: Carrier components; as well as A load-applying element disposed between the buckle and the carrier member, wherein the load-applying element is configured to push the first surface of the buckle against a polishing pad when a positive pressure is applied within the inner region of the load-applying element.

6. The substrate carrier of claim 5, wherein each of the plurality of carrier pins is fixed relative to the carrier member.

7. The substrate carrier of claim 1, wherein when the length of the body of each of the carrier pins is vertically oriented, each of the plurality of carrier pins has a horizontal width at an end of the length of the body of the carrier pin that is greater than the horizontal width of the remainder of the length of the carrier pin disposed within the recess.

8. A substrate carrier for polishing the surface of a substrate, characterized in that... include: A retaining ring, configured to surround a substrate during a polishing process, the retaining ring comprising: A first surface, the first surface being configured to contact the surface of the polishing pad during the polishing process; The second surface is on the side of the clasp opposite to the first surface; and An array of recesses formed in the second surface; A plurality of carrier pins, each of the plurality of carrier pins having a contact shoulder capable of being positioned relative to the surface of the recess in which the carrier pin is disposed during the polishing process; and One or more actuator assemblies are coupled to one or more of the plurality of carrier pins, the actuator assemblies being configured to adjust the position of the contact shoulder of one or more of the plurality of carrier pins relative to the surface of the recess in which the carrier pin is disposed.

9. The substrate carrier of claim 8, wherein each of the plurality of carrier pins further comprises a body having a length, and wherein at least a portion of the length of each of the plurality of carrier pins is disposed within each recess in the array of recesses.

10. The substrate carrier of claim 9, wherein when the length of the body of each of the carrier pins is vertically oriented, each of the plurality of carrier pins has a horizontal width at an end of the length of the body of the carrier pin that is greater than the horizontal width of the remainder of the length of the carrier pin disposed within the recess.

11. The substrate carrier of claim 8, wherein the substrate carrier further comprises: Carrier components, The one or more actuator components further include: A return spring, wherein the return spring is disposed between a portion of the carrier member and a portion of each of the plurality of carrier pins; and A force actuator coupled to the carrier member and configured to compress or decompress the return spring when the position of the contact shoulder is adjusted relative to the surface of the recess.

12. The substrate carrier of claim 8, wherein the ratio of the number of actuator assemblies to the number of support pins is between 1:3 and 1:

1.

13. A method of polishing a substrate, comprising: include: The portion of the bearing pin is positioned in each of the arrays of recesses formed in the first surface of the retaining ring, wherein The retaining ring includes a polishing pad contact surface positioned on a side of the retaining ring opposite to the side on which the first surface is disposed, and the retaining ring is configured to surround the substrate during the polishing process. The portion in which the support pin is positioned within the recess includes a contact shoulder. Rotate the substrate carrier assembly around the central carrier axis; as well as The polishing pad contact surface of the buckle is pushed against the surface of the polishing pad. The contact shoulder of each of the carrier pins is positionable relative to the surface of the recess in which the carrier pin is disposed during the polishing process.

14. The method of claim 13, wherein the method further comprises adjusting the position of the contact shoulder of the carrier pin relative to the surface of the recess in which the carrier pin is disposed during the polishing process.

15. The method of claim 14, wherein adjusting the position of the contact shoulder of the bearing pin comprises: Adjust the amount of force supplied to the bearing pin by the force actuator.

16. The method of claim 14, wherein the method further comprises adjusting, during the polishing process, the position of the contact shoulder of each carrier pin in each recess of the array of recesses relative to the surface of the recess in which the carrier pin is disposed.

17. The method of claim 14, wherein adjusting the position of the contact shoulder of the bearing pin comprises: A spring is compressed between a portion of the support pin and a portion of the substrate carrier assembly.

18. The method of claim 13, wherein the method further comprises: The polishing pad contact surface of the buckle is pushed against the polishing pad by applying positive pressure to the inner region of the load application member disposed between the portion of the buckle and the portion of the substrate carrier assembly.

19. The method of claim 18, wherein each of the carrier pins is fixed relative to the portion of the substrate carrier assembly.

20. The method of claim 13, wherein the contact shoulder of each carrier pin has a greater horizontal width than the rest of the carrier pin.

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