CHEMICAL MECHANICAL POLISH PAD CONDITIONER WITH MULTIPLE DISKS

BACKGROUND
Field

Embodiments of the present invention generally relate to a polishing pad conditioner for use in chemical mechanical polishing.

Description of the Related Art

Integrated circuits are typically formed on a substrate, particularly a silicon wafer, by the sequential deposition of conductive, semiconductive, or insulative layers. After each layer is deposited, the layer is etched to create circuitry features. As a series of layers are sequentially deposited and etched, the outer or uppermost surface of the substrate, i.e., the exposed surface of the substrate, becomes increasingly non-planar. This non-planar surface presents problems in subsequent photolithographic steps of the integrated circuit fabrication process. Therefore, there is a need to periodically planarize the substrate surface.

Chemical mechanical polishing (CMP) is one accepted method of planarization. This planarization method typically requires that the substrate be mounted on a carrier or polishing head. The exposed surface of the substrate is placed against a rotating polishing pad. The polishing pad may be a “standard” pad in which the polishing pad surface is a durable, roughened surface, or a fixed abrasive pad in which abrasive particles are held in a containment media. The carrier head provides a controllable load, i.e., pressure, on the substrate to push it against the polishing pad. A polishing slurry, including at least one chemically-reactive agent, and abrasive particles if a standard pad is used, is supplied to the polishing pad.

In typical CMP processing, a substrate is pressed against the rotating polishing pad on which the polishing slurry is flowed. Material formed along the substrate is removed through a combination of chemical interaction of the polishing slurry and mechanical interaction with the polishing pad. As processes increase in complexity, and non-uniformity of material formation on a substrate increases, standard chemical-mechanical polishing systems may be incapable of adequately responding to material structures to be polished.

Thus, there is a need for improved systems and methods that can be used to improve systems for increased polishing and removal precision.

SUMMARY

Embodiments described herein generally relate to systems and methods used for conditioning a pad during semiconductor processing. More particularly, embodiments herein provide for a pad conditioner with multiple diamond disks for chemical mechanical polishing.

In an embodiment, a pad conditioner is provided. The pad conditioner includes a shaft, a bearing ring connected to a lower portion of the shaft, the bearing ring contacting a rolling element, an outer disk assembly connected to the lower portion of the shaft, the outer disk assembly having an outer disk main body, an outer disk flexure connected to the outer disk main body and the lower portion of the shaft, a plurality of outer disks disposed on a bottom surface of the outer disk main body, and an inner disk assembly connected to the lower portion of the shaft concentrically to the outer disk assembly. The inner disk assembly includes an inner disk main body, an inner disk flexure connected to the inner disk main body, and a plurality of inner disks disposed on a bottom surface of the inner disk main body.

In another embodiment, a pad conditioner is provided. The pad conditioner includes a shaft, a bearing ring connected to a lower portion of the shaft, the bearing ring contacting a rolling element, an outer disk assembly connected to the lower portion of the shaft, the outer disk assembly having a plurality of outer disk holders, an outer disk connector connecting the plurality of outer disk holders, and a plurality of outer disks disposed on a bottom surface of the outer disk holders, and an inner disk assembly connected to the lower portion concentrically to the outer disk assembly. The inner disk assembly includes a plurality of inner prongs, a plurality of inner disks disposed on a bottom surface of the inner prongs, and a flexure connected to the outer disk assembly, the inner disk assembly, and the shaft.

In yet another embodiment, a pad conditioner is provided. The pad conditioner includes a shaft, a spherical bearing assembly coupled to a lower portion of the shaft, an outer disk assembly connected to the lower portion of the shaft, the outer disk assembly having an outer disk main body, and a plurality of outer disks disposed on a bottom surface of the outer disk main body, and an inner disk assembly connected to the lower portion concentrically to the outer disk assembly. The inner disk assembly includes an inner disk main body, a plurality of inner disks disposed on a bottom surface of the inner disk main body, and a flexure connected to the outer disk assembly and the shaft.

BRIEF DESCRIPTION OF THE DRAWINGS

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

FIG. 1 shows a schematic cross-sectional view of an exemplary processing system according to some embodiments.

FIG. 2A is a schematic isometric view of a pad conditioner, according to some embodiments.

FIG. 2B is a schematic bottom view of the pad conditioner of FIG. 2A, according to some embodiments.

FIG. 2C shows a schematic cross-sectional view of the pad conditioner of FIG. 2A, according to some embodiments.

FIG. 3A is a schematic cross-sectional view of a pad conditioner, according to some embodiments.

FIG. 3B is a schematic bottom view of the pad conditioner of FIG. 3A, according to some embodiments.

FIG. 4A is a schematic cross-sectional view of a pad conditioner, according to some embodiments.

FIG. 4B is a schematic bottom view of the pad conditioner of FIG. 4A, according to some embodiments.

FIG. 5A is a schematic cross-sectional view of a pad conditioner, according to some embodiments.

FIG. 5B is a schematic bottom view of the pad conditioner of FIG. 5A, according to some embodiments.

FIG. 6A is a schematic cross-sectional view of a pad conditioner, according to some embodiments.

FIG. 6B is a schematic top view of a first disk assembly of the pad conditioner shown in FIG. 6A, according to some embodiments.

FIG. 6C is a schematic top view of a second disk assembly of the pad conditioner shown in FIG. 6A, according to some embodiments.

FIG. 7A is a schematic cross-sectional view of a pad conditioner, according to some embodiments.

FIG. 7B is a schematic bottom view of the pad conditioner shown in FIG. 7A, according to some embodiments.

FIG. 7C is a schematic bottom view of a flexure of the pad conditioner shown in FIG. 7A, according to some embodiments.

FIG. 8A is a schematic cross-sectional view of a pad conditioner, according to some embodiments.

FIG. 8B is a schematic bottom view of the pad conditioner shown in FIG. 8A, according to some embodiments.

FIG. 8C is a schematic cross-sectional bottom view of the pad conditioner shown in FIG. 8A, according to some embodiments.

FIG. 9A is schematic cross-sectional view of a pad conditioner, according to some embodiments.

FIG. 9B is a schematic cross-sectional view of a spherical bearing assembly of the pad conditioner shown in FIG. 9A, according to some embodiments.

FIG. 9C is a schematic cross-sectional view of a cam assembly of the spherical bearing assembly shown in FIG. 9B.

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

DETAILED DESCRIPTION

Embodiments herein are generally directed to a processing chamber and, more particularly, to systems and methods for conditioning a polishing pad during chemical mechanical polishing (CMP). More particularly, embodiments provided herein include improved systems and methods for adjusting pressure applied to the polishing pad from a polishing pad conditioning assembly based on the polishing pad surface.

Polishing pad conditioners may be provided with multiple small diamond disks to improve uniformity of the polishing pad. The diamond disks in the polishing pad conditioner each have a gimbal to improve the conformability between individual small diamond disks and the polishing pad surface. The complexity of each of the individual gimbals, however, decreases the reliability of the diamond disks and, ultimately, the polishing pad conditioner. Accordingly, the present disclosure provides a technical solution to the reliability issues of individual gimbals on the diamond disks by providing a polishing pad conditioner with concentric disk assemblies and a gimbal assembly configured to adjust the concentric disk assemblies.

Specifically, a polishing pad conditioner is described that includes at least two concentric disk assemblies, e.g., one inner disk assembly and one outer disk assembly, and at least one flexure. Each disk assembly may include a flexure, a main body, and a plurality of diamond disks. Alternatively, the polishing pad conditioner may only have one flexure connected to the first disk assembly and the outer disk assembly. Each disk assembly may have any desired shape. For example, the inner disk assembly may have a substantially round shape and the outer disk shape may have a substantially toroidal or “donut” shape. Additional concentric disk assemblies may be between the inner disk assembly and the outer disk assembly. Alternatively, the first disk assembly and second disk assembly may have a pronged shape such that the main body has prongs radially extending from a center portion. For example, the first disk assembly and the second disk assembly may each have three prongs. In such a configuration, the first disk assembly is overlaid on the second disk assembly such that the prongs of the first disk assembly are radially equidistant from the prongs of the second disk assembly.

The flexures allow the concentric disk assemblies to evenly distributed pressure to the diamond disks on each of the assemblies by adjusting the orientation of the diamond disks and the disk assemblies using the polishing pad surface. Doing so improves the pad conditioning efficiency by improving the conformability between the individual small diamond disks of each disk assembly and the polishing pad surface. The ex-situ polishing pad conditioning time is also shortened, improving throughput and process stability.

FIG. 1 illustrates a schematic cross-sectional view of an exemplary polishing system 100 according to some embodiments of the present technology. Polishing system 100 includes a platen assembly 102, which includes a lower platen 104 and an upper platen 106. Lower platen 104 may define an interior volume or cavity through which connections can be made, as well as in which may be included end-point detection equipment or other sensors or devices, such as eddy current sensors, optical sensors, or other components for monitoring polishing operations or components. For example, and as described further below, fluid couplings may be formed with lines extending through the lower platen 104, and which may access the upper platen 106 through a backside of the upper platen. Platen assembly 102 may include a polishing pad 110 mounted on a first surface of the upper platen 106. A substrate carrier 108, or carrier head, may be disposed above the polishing pad 110 and may face the polishing pad 110. The platen assembly 102 may be rotatable about an axis A, while the substrate carrier 108 may be rotatable about an axis B. The substrate carrier 108 may also be configured to sweep back and forth from an inner radius to an outer radius along the platen assembly 102, which may, in part, reduce uneven wear of the surface of the polishing pad 110. The polishing system 100 may also include a fluid delivery arm 118 positioned above the polishing pad 110, and which may be used to deliver polishing fluids, such as a polishing slurry, onto the polishing pad 110. Additionally, a pad conditioning assembly 120 may be disposed above the polishing pad 110, and may face the polishing pad 110.

In some embodiments of performing a chemical mechanical polishing process, the rotating or sweeping substrate carrier 108 may exert a downforce against a substrate 112, which is shown in phantom and may be disposed within or coupled with the substrate carrier 108. The downward force applied may depress a material surface of the substrate 112 against the polishing pad 110 as the polishing pad 110 rotates about the axis A of the platen assembly 102. The interaction of the substrate 112 against the polishing pad 110 may occur in the presence of one or more polishing fluids delivered by the fluid delivery arm 118. A typical polishing fluid may include a slurry formed of an aqueous solution in which abrasive particles may be suspended. Often, the polishing fluid contains a pH adjuster and other chemically active components, such as an oxidizing agent, which may enable chemical mechanical polishing of the material surface of the substrate 112.

The pad conditioning assembly 120 may be operated to apply a fixed abrasive conditioning disk 122 against the surface of the polishing pad 110, which may be rotated as previously noted. The conditioning disk may be operated against the pad prior to, subsequent to, or during polishing of the substrate 112. Conditioning the polishing pad 110 with the conditioning disk 122 may maintain the polishing pad 110 in a desired condition by abrading, rejuvenating, and removing polish byproducts and other debris from the polishing surface of the polishing pad 110.

The pad conditioning assembly 120 may include multiple small diamond disks mounted on concentric disk holder assemblies where each of the assemblies includes flexures to improve pad conditioning efficiency as described in FIGS. 2A and 2B.

FIG. 2A is a schematic isometric view of a pad conditioner 200 (e.g., pad conditioning assembly 120), and FIG. 2B is a schematic bottom view of the pad conditioner 200 according to an embodiment. The pad conditioner 200 includes an outer disk assembly 210, an inner disk assembly 220, a shaft 202 along an axis 204, and a gimbal assembly 206 attached to the shaft 202. The outer disk assembly 210 and the inner disk assembly 220 are concentrically aligned along axis 204. The outer disk assembly 210 includes outer apertures 216 through a top surface 218. The outer apertures 216 allow a slurry to enter and pass through the pad conditioner 200 during a polishing process. The outer disk assembly 210 includes a bottom surface 212 that has a toroidal or “donut” shape and has a plurality of outer disks 214 disposed thereon. The inner disk assembly 220 includes a bottom surface 222 that has a circular shape and has a plurality of inner disks 224 disposed thereon. The bottom surface 222 also includes inner apertures 226 disposed therethrough. The inner apertures 226, like outer apertures 216, allow a polishing slurry to pass through the pad conditioner 200.

FIG. 2C shows a schematic cross-sectional view of the pad conditioner 200. As shown in FIG. 2C, the pad conditioner 200 is attached to an arm 208a of the polishing system 100 (FIG. 1) by inserting a proximal end of the shaft 202 into the arm 208a and secured using a shaft clamp 208b that is tightened with a screw 208c. A distal end of the shaft 202 is attached to the gimbal assembly 206. The gimbal assembly 206 includes an upper portion 230 and a lower portion 240. The upper portion 230 includes a concentric flexure 232. The concentric flexure 232 allows the gimbal assembly 206 to flex around the shaft 202. The lower portion 240 connects to a bearing ring 242 which circumferentially contacts a rolling element 244. The shaft 202 connects to the rolling element 244. For example, the shaft 202 may be connected to an outer surface of the rolling element 244, the shaft 202 may be inserted into the rolling element 244 as shown, or a combination thereof. The rolling element 244 and the bearing ring 242 interact such that the bearing ring 242 may rotate about the rolling element 244. The rolling element 244 and the bearing ring 242 allow for angle compensation, e.g., gross alignment of the pad conditioner 200, from forces applied to the inner disks 224 and the outer disks 214 by the polishing pad 110 during conditioning.

The outer disk assembly 210 may be connected to a proximate end 240a of the lower portion 240. The outer disk assembly 210 includes an outer disk flexure 250 located on the top surface 218, concentric with axis 204, and directly connected on one end to the lower portion 240 of the gimbal assembly 206. The outer disk flexure 250 is connected to an outer disk main body 210a of the outer disk assembly 210 at an end of the outer disk flexure 250 opposite the lower portion 240. A lateral gap 252 exists between the outer disk main body 210a and the inner disk assembly 220. A longitudinal gap 254 also exists between the outer disk flexure 250 and the inner disk assembly 220. The lateral gap 252 and the longitudinal gap 254 allow the outer disk flexure 250 to deform with respect to the inner disk assembly 220 and the gimbal assembly 206 as a force is applied to the outer disks 214.

The inner disk assembly 220 may be connected to the distal end 240b of the lower portion 240 at a center portion 220a of the inner disk assembly 220. The inner disk assembly 220 includes an inner disk flexure 260 located on the bottom surface 222 of the inner disk assembly 220 between the center portion 220a and an inner disk main body 220b of the inner disk assembly 220. A lateral gap 264 exists between the center portion 220a and the inner disk main body 220b of the inner disk assembly 220. A longitudinal gap 262 also exists between the inner disk flexure 260 and the lower portion 240 of the gimbal assembly 206. The lateral gap 264 and the longitudinal gap 262 allow the inner disk flexure 260 to deform with respect to the inner disk assembly 220 and the gimbal assembly 206 as a force is applied to the inner disks 224.

The outer disk flexure 250 and the inner disk flexure 260 compensate for misalignment of the outer disk assembly 210 and the inner disk assembly 220, respectively, from forces caused by uneven polishing pad surfaces during pad conditioning which improves pad conditioning efficiency and conformability between the inner disks 224 and the outer disks 214 and the polishing pad 110 surface.

The placement of the inner disk flexure 260 relative to the inner disk main body 220b of the inner disk assembly 220, shown at the bottom surface 222 in FIG. 2C, may be at any desired location. For example, the inner disk flexure 260 may be located at a surface that does not contact the polishing pad 110 during pad conditioning, as illustrated in FIGS. 3A and 3B.

FIG. 3A is a schematic cross-sectional view of a pad conditioner 300 (e.g., pad conditioning assembly 120), and FIG. 3B is a schematic bottom view of the pad conditioner 300 according to another embodiment. FIGS. 3A and 3B show the pad conditioner 300 having concentric disk holder assemblies. An outer disk assembly 310 and an inner disk assembly 320 are attached to a shaft 302 concentrically along axis 304. The outer disk assembly 310 includes an outer disk flexure 350 connected to, via an outer disk connection 310a, an outer disk body 310b. The outer disk body 310b has a bottom surface 312 that includes a plurality of outer disks 314. The outer disk assembly 310 also includes a lateral gap 352, located between the outer disk body 310b and the inner disk assembly 320, and a longitudinal gap 354, located between the outer disk flexure 350 and the inner disk assembly 320.

The inner disk assembly 320 is attached to a distal end of the shaft 302 at a center portion 320a of the inner disk assembly 320. The inner disk assembly 320 includes an inner disk flexure 360 radially connected to the center portion 320a. An inner disk body 320b is connected to the inner disk flexure 360 via an inner disk connection 320c. The inner disk body 320b has a bottom surface 322 that includes a plurality of inner disks 324. The inner disk assembly 320 also includes a radial gap 362 between the inner disk flexure 360 and the inner disk body 320b. The radial gap 362 also includes a width between the center portion 320a and the inner disk connection 320c.

The radial gap 362 is configured to allow deformation of the inner disk flexure 360 in response to an uneven polishing pad 110 surface during pad conditioning. The inner disk body 320b is rigid such that the misalignment adjustment is accomplished substantially by the inner disk flexure 360.

Although the outer disk assembly 310 and the inner disk assembly 320 have uniform toroidal and circular shapes, the disk assemblies, particularly the disk holders, may have any desired shape such as ovals, illustrated in FIGS. 4A-4B, or prongs, illustrated in FIGS. 5A-6C.

FIG. 4A is a schematic cross-sectional view of a pad conditioner 400 (e.g., pad conditioning assembly 120), and FIG. 4B is a schematic bottom view of the pad conditioner 400 according to another embodiment. As shown in FIGS. 4A and 4B, the pad conditioner 400 includes an outer disk assembly 410 and an inner disk assembly 420. The outer disk assembly 410 includes an outer disk flexure 450 attached to a shaft 402 concentrically about axis 404. A plurality of outer disk holders 410a are radially attached to the outer disk flexure 450 by an outer flexure connector 410b. The plurality of outer disk holders 410a are connected to each other by an outer disk connector 410c. The plurality of outer disk holders 410a may have an oval shape with a bottom surface 412 that includes a plurality of outer disks 414.

The outer disk assembly 410 includes a first lateral gap 452a between the plurality of outer disk holders 410a and the inner disk assembly 420 and a second lateral gap 452b between the outer disk connector 410c and the inner disk assembly 420. The outer disk assembly 410 also includes a first longitudinal gap 454a between the outer disk flexure 450 and the plurality of outer disk holders 410a and a second longitudinal gap 454b between the outer disk flexure 450 and the inner disk assembly 420.

The inner disk assembly 420 includes a first inner disk flexure 460a and a second inner disk flexure 460b connected radially about an inner disk center portion 420a. The inner disk center portion 420a is directly connected to an inner disk body 420b. The first inner disk flexure 460a and the second inner disk flexure 460b are radially connected to the inner disk body 420b via an inner flexure connector 420c. The inner disk body 420b has a bottom surface 422 that includes a plurality of inner disks 424.

The inner disk body 420b has a shape that is complimentary to the shape of the outer disk holders 410a and the outer disk connector 410c. For example, the inner disk body 420b may have a circular shape with recesses to accommodate each of the outer disk holders 410a.

The inner disk assembly 420 includes a first lateral gap 462 and second lateral gap 464. The first lateral gap 462 is located between the inner disk center portion 420a and the inner flexure connector 420c proximate to the outer disk holders 410a. The second lateral gap 464 is located between the inner disk center portion 420a and the inner flexure connector 420c proximate to the outer disk connector 410c. The first lateral gap 462 and the second lateral gap 464 may have different widths to accommodate the shape of the inner disk body 420b. For example, the first lateral gap 462 may have a width such that the first lateral gap 452a between the inner disk assembly 420 and the outer disk holders 410a is maintained. The second lateral gap 464 may have a width such that the second lateral gap 452b between the inner disk assembly 420 and the outer disk connector 410c is maintained.

FIG. 5A is a schematic cross-sectional view of a pad conditioner 500 (e.g., pad conditioning assembly 120), and FIG. 5B is a schematic bottom view of the pad conditioner 500 according to another embodiment. The pad conditioner 500 has a first disk assembly 510 and a second disk assembly 520 that are concentric about axis 504. The first disk body assembly 510 includes a first disk body 510a that has a first bottom surface 512 that having a plurality of first disks 514 coupled thereto. The first disk body 510a includes a first plurality of prongs 510b extending radially from a first central portion 510c. Each of the first plurality of prongs 510b includes at least one of the plurality of first disks 514. A first flexure 550 is radially attached to a shaft 502 and connects to each of the first plurality of prongs 510b. The first flexure 550 is planar and allows for flexion of each of the first plurality of prongs 510b when a force acts upon the first bottom surface 512.

The second disk assembly 520 includes a second disk body 520a with a second plurality of prongs 520b extending radially from a second central portion 520c. The shaft 502 extends through the first central portion 510c and connects to the second central portion 520c. The second plurality of prongs 520b includes a second bottom surface 522 that has a second plurality of disks 524. Each of the second plurality of prongs 520b includes at least one of the second plurality of disks 524. Each of the first plurality of prongs 510b are separated by a radial distance 530 from each of the second plurality of prongs 520b. A second flexure 560 extends radially from the shaft 502 and connects to each of the second plurality of prongs 520b. The second flexure 560 is planar and allows for flexion of each of the second plurality of prongs 520b when a force acts upon the second bottom surface 522.

The first flexure 550 and the second flexure 560 may be configured to provide a desired level of flexion in response to pressure provided by the plurality of disks 514, 524 or from the shaft 502. The first flexure 550 and the second flexure 560 may have a thickness that, depending on the material of the respective flexure, allows for flexion while preventing permanent deformation or breakage of the flexure. The shape of the first flexure 550 and the second flexure 560 may contribute to such properties and, as such, the first flexure 550 and the second flexure 560 may be flat or have any desired shape, as illustrated in FIGS. 6A-6C.

FIG. 6A is a schematic cross-sectional view of a pad conditioner 600 (e.g., pad conditioning assembly 120), according to one embodiment. FIG. 6B is a schematic top view of a first disk assembly 610 of the pad conditioner 600. FIG. 6C is a schematic top view of a second disk assembly 620 of the pad conditioner 600. FIGS. 6A-6C show the pad conditioner 600 similarly configured to the pad conditioner 500 shown in FIGS. 5A and 5B. The first disk assembly 610 and the second disk assembly 620 are connected to a shaft 602 concentrically about axis 604. The first disk assembly 610 includes a first flexure 650 that is connected at one end to a first stop 652 on the shaft 602. The second disk assembly 620 includes a second flexure 660 attached at one end to a second stop 662 of the shaft 602. The second stop 662 is located along the shaft 602 between a portion of the first disk assembly 610 and the second disk assembly 620, resulting in an offset of the second flexure 660 relative to the first flexure 650. The first stop 652 allows the first flexure 650 to deform when pressure is applied to a first set of disks 614 attached to the first disk assembly 610 while the second stop 662 allows the second flexure 660 to deform when pressure is applied to a second set of disks 624 of the second disk assembly 620. The first flexure 650 and the second flexure 660 have an s-shape to aid in flexion when force is applied to the first disk assembly 610 or second disk assembly 620. Offset flexures, such as the first flexure 650 and the second flexure 660, allow for a greater range of orthogonal displacement resulting in better adjustments of each of the first set of disks 614 and the second set of disks 624.

FIG. 7A is a schematic cross-sectional view of a pad conditioner 700, according to some embodiments. FIG. 7B is a schematic bottom view of the pad conditioner 700 shown in FIG. 7A, according to some embodiments. FIGS. 7A and 7B illustrate the pad conditioner 700 comprising an outer disk assembly 710 and an inner disk assembly 720 connected concentrically about axis 704. A flexure 750 connects the outer disk assembly 710 and the inner disk assembly 720 to a shaft 702 such that the outer disk assembly 710 and the inner disk assembly 720 are coplanar. Alternatively, the outer disk assembly 710 and the inner disk assembly 720 may be offset as discussed regarding FIGS. 6A-6C. The outer disk assembly 710 is connected to the flexure 750 via a set of fasteners 752. The outer disk assembly 710 includes a plurality of outer disk holders 710a connected to each other via an outer disk connector 710b. Each of the plurality of outer disk holders 710a has a bottom surface 712 that has a plurality of outer disks 714. The plurality of outer disks 714 are connected to the outer disk holders 710a using fasteners 752.

The inner disk assembly 720 includes a plurality of inner prongs 720a connected to an inner central portion 720b. Each of the inner prongs 720a is connected to the flexure 750 via the fasteners 752. Each of the plurality of inner prongs 720a includes one of a plurality of inner disks 724 on a bottom surface 722 of the inner disk assembly 720. Each of the plurality of outer disks 714 is a radial distance 760 from each of the plurality of inner disks 724 such that the plurality of outer disks 714 and the plurality of inner disks 724 are radially equidistant from each other about the axis 704.

FIG. 7C is a schematic bottom view of the flexure 750 of the pad conditioner 700. Referring to FIG. 7C, the flexure 750 has a plurality of flexure prongs 754 equal to the sum of the number of inner prongs 720a and the number of outer disk holders 710a. The plurality of flexure prongs 754 are arranged radially about the axis 704 and aligned with the inner prongs 720a and the outer disk holders 710a. Each of the plurality of flexure prongs 754 are connected to the outer disk connector 710b and include the fasteners 752. Each of the plurality of flexure prongs 754 are deformable about the center of the flexure 750, allowing each of the plurality of inner prongs 720a and each of the plurality of outer disk holders 710a to deform the flexure 750 independently. Such an arrangement allows each disk assembly to deform the flexure without interfering with the diamond disks of the other disk assembly when a downward force is applied by the shaft during pad conditioning

The gimbal assembly (e.g., gimbal assembly 206) that interacts with the concentric disk assemblies may also be adjusted. In the above examples, the gimbal assembly adjusts the pad conditioner (200, 300, 400, 500, 600, 700) as a whole while the flexures (250, 260, 350, 360, 450, 460a, 460b, 550, 560, 650, 660, 750) provide adjustments to the individual disk assemblies (210, 220, 310, 320, 410, 420, 510, 520, 610, 620, 710, 720). The gimbal assembly may be configured to adjust, in conjunction with the flexures and the individual disk assemblies as described below.

FIG. 8A is a schematic cross-sectional view of a pad conditioner 800, according to some embodiments. FIG. 8B is a schematic bottom view of the pad conditioner 800. FIG. 8C is a schematic cross-sectional bottom view of the pad conditioner 800. FIGS. 8A-8C show the pad conditioner 800 with concentric disk assemblies, e.g., an outer disk assembly 810 and an inner disk assembly 820, connected to a shaft 802 concentric about axis 804, and a spherical bearing 840. A flexure 850 is radially connected at one end to the shaft 802 at a base 806 located at a distal end of the shaft 802. The flexure 850 is connected at an opposite end to the outer disk assembly 810. The spherical bearing 840 is connected to the base 806.

The outer disk assembly 810 includes a plurality of outer disk holders 812 connected to each other by an outer disk connector 810a. The plurality of outer disk holders 812 contact the spherical bearing 840 on an inner side and function as a bearing ring for the spherical bearing 840 such that the spherical bearing 840 may contact the plurality of outer disk holders 812 and allow the plurality of outer disk holders 812 to rotate about the spherical bearing 840. The outer disk holders 812 may each be bifurcated into an upper outer disk holder 812a and a lower outer disk holder 812b. The upper outer disk holder 812a is connected to the flexure 850. The lower outer disk holder 812b is connected to the upper outer disk holder 812a with a set of upper fasteners 852a. The outer disk holders 812 include a plurality of outer disks 814 that are connected to the lower outer disk holders 812b by a set of lower fasteners 852b.

The inner disk assembly 820 includes a plurality of inner disk holders 822 connected to each other by the outer disk connector 810a. The plurality inner disk holders 822 contact the spherical bearing 840 on an inner side and function as a bearing ring for the spherical bearing 840 similar to the outer disk holders 812. The spherical bearing 840 is configured to contact the inner side of the plurality of outer disk holders 812 and the plurality of inner disk holders 822 simultaneously. The inner disk holders 822 may each be bifurcated into an upper inner disk holder 822a and a lower inner disk holder 822b. Like the upper outer disk holder 812a and lower outer disk holder 812b, the upper inner disk holder 822a and lower inner disk holder 822b are connected to each other with the upper fasteners 852a. The upper inner disk holder 822a is connected to the flexure 850. The lower inner disk holders 822b includes a plurality of inner disks 824 with the lower fasteners 852b. The inner disk holders 822 are connected to each other by a central portion 820a of the inner disk assembly 820 coaxially located about the axis 804.

The spherical bearing 840 of pad conditioner 800 is shown as a single piece, but a spherical bearing assembly may be used where a spherical bearing is divided into multiple parts to further control how much each disk assembly is adjusted. Such an example is illustrated in FIGS. 9A-9C.

FIG. 9A is schematic cross-sectional view of a pad conditioner 900, according to some embodiments. FIG. 9B is a schematic cross-sectional view of a spherical bearing assembly 940 of the pad conditioner 900, according to some embodiments. FIG. 9C is a schematic cross-sectional view of a cam assembly 960 of the spherical bearing assembly 940. FIGS. 9A-9C show the pad conditioner 900 similarly configured to pad conditioner 800. The pad conditioner 900 includes an outer disk assembly 910 and an inner disk assembly 920 arranged concentrically about axis 904 and connected to shaft 902 by a flexure 950. The outer disk assembly 910 and the inner disk assembly 920 are connected to the flexure 950 directly. The outer disk assembly 910 includes a plurality of outer disk holders 912 configured to contact a spherical bearing assembly 940, each bifurcated into an upper outer disk holder 912a and lower outer disk holder 912b, an outer disk connector 910a, a plurality of outer disks 914, a set of upper fasteners 952a, a set of lower fasteners 952b, and a set of flexure fasteners 952c. The flexure fasteners 952c connect the flexure 950 to the outer disk assembly 910, e.g., to the upper outer disk holder 912a, and the inner disk assembly 920.

The inner disk assembly 920, like the inner disk assembly 820 shown in FIGS. 8A-8C, includes a plurality of inner disk holders 922 configured to contact the spherical bearing assembly 940, each bifurcated into an upper inner disk holder 922a and lower inner disk holder 922b and connected to the outer disk connector 910a and a central portion 920a, a plurality of inner disks 924.

As shown in FIG. 9B, the spherical bearing assembly 940 includes an outer spherical bearing 942 and an inner spherical bearing 944 overlapping concentrically about axis 904. The outer spherical bearing 942 includes a curved bearing face 942a configured to interact with the outer disk assembly 910, the inner disk assembly 920, or a combination thereof. The inner spherical bearing 944 includes a curved bearing face 944a configured to interact with the outer disk assembly 910, the inner disk assembly 920, or a combination thereof.

Referring to FIG. 9C, the outer spherical bearing 942 and the inner spherical bearing 944 include an outer bearing protrusion 942b and an inner bearing protrusion 944b, respectively, configured to interact with the shaft 902, the base 906, each other, or a combination thereof. The distal end of the shaft 902 houses a cam assembly 960. The cam assembly 960 includes a cam 962 attached to a shaft support 964 by a rod 966. The cam 962 is grooved and configured to rotate about the rod 966. The inner bearing protrusion 944b contacts one side of the grooved cam 962 and the outer bearing protrusion 942b contacts the opposing side of the grooved cam 962. As the shaft 902 exerts a downward force, the reactive force pushes up on the inner spherical bearing 944 and outer spherical bearing 942. The inner bearing protrusion 944b and the outer bearing protrusion 942b distribute the reactive force on the cam 962, causing the cam 962 to rotate. The rotation of the cam 962 allows the exerted force and resulting pressure on the inner disks 924 and outer disks 914 to be evenly distributed by adjusting the gross alignment of the pad conditioner.

The disclosed subject matter allows the diamond disks of each assembly to be adjusted using the polishing pad surface such that the pressure each diamond disk exerts on the polishing pad as pad conditioning occurs is uniform while also remaining cost effective. Adjusting the diamond disks as part of concentric assemblies improves the pad conditioning efficiency by improving the conformability between the individual small diamond disks of each disk assembly and the polishing pad surface. Further, the ex-situ pad conditioning time is shortened and the throughput and process stability is improved.

When introducing elements of the present disclosure or exemplary aspects or embodiments thereof, the articles “a,” “an,” “the” and “said” are intended to mean that there are one or more of the elements.

The terms “comprising,” “including” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.

The term “coupled” is used herein to refer to the direct or indirect coupling between two objects. For example, if object A physically touches object B and object B touches object C, the objects A and C may still be considered coupled to one another-even if objects A and C do not directly physically touch each other. For instance, a first object may be coupled to a second object even though the first object is never directly in physical contact with the second object.

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

CHEMICAL MECHANICAL POLISH PAD CONDITIONER WITH MULTIPLE DISKS

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CPC

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