CN110948392A

CN110948392A - Multi-zone pad conditioning disk

Info

Publication number: CN110948392A
Application number: CN201910917992.7A
Authority: CN
Inventors: 斯坦·D·蔡; 卢克·S·蔡
Original assignee: Canna Diamond Technology Co Ltd
Current assignee: Canna Diamond Technology Co Ltd
Priority date: 2018-09-26
Filing date: 2019-09-26
Publication date: 2020-04-03
Also published as: KR20200035367A; US20200094375A1; TW202015861A

Abstract

A pad conditioning disk configured to condition a polishing pad of a chemical mechanical polishing tool includes a plurality of regions including cutting elements that selectively engage the polishing pad based on positioning of the plurality of regions. The invention also provides chemical mechanical polishing tools and methods related to conditioning polishing pads during Chemical Mechanical Polishing (CMP).

Description

Multi-zone pad conditioning disk

Cross Reference to Related Applications

The present application claims the benefit and priority of U.S. provisional application No. 62/737,078 entitled "pad conditioning disks with Multiple Zones" (filed on 26.09.2018).

Technical Field

The present invention relates to pad conditioning disks, and more particularly to multi-zone pad conditioning disks for use with chemical mechanical polishing tools.

Background

Chemical mechanical polishing or planarization (CMP) is a polishing process for silicon wafers and other substrates that utilizes a polishing solution on a polishing pad and its chemical and abrasive agents, in combination with chemical and mechanical effects, for removing excess material from the surface and for obtaining a desired thickness of silicon wafers and other substrates having a smooth and flat surface. Polishing pads used for successful CMP require optimal surface porosity and tend to lose surface porosity due to surface degradation over time. Polishing pad conditioning disks are a key element of CMP technology used to establish, maintain, and recreate the optimal surface porosity of a polishing pad.

Disclosure of Invention

One aspect of the invention relates to a pad conditioning disk configured to condition a polishing pad of a chemical mechanical polishing tool, comprising a plurality of regions including cutting elements that selectively engage the polishing pad based on positioning of the plurality of regions.

In an exemplary embodiment, the plurality of regions are movable relative to each other.

In an exemplary embodiment, the plurality of zones are movable relative to each other such that the cutting elements of a first zone of the plurality of zones are in contact with the polishing pad during chemical mechanical polishing, while the cutting elements of a second zone of the plurality of zones are not in contact with the polishing pad.

In an exemplary embodiment, a first region of the plurality of regions comprises particulate diamond having a shape, size, distribution, and density, and a second region of the plurality of regions comprises a Chemical Vapor Deposition (CVD) diamond film coated on the textured surface.

In exemplary embodiments, the cutting elements of each region are diamond or diamond-like film of the same shape, size, distribution, density, and structure, or the cutting elements of each region are diamonds of different shape, size, distribution, density, and structure.

In an exemplary embodiment, the connecting means operatively connects the plurality of regions and facilitates independent movement between the plurality of regions.

In an exemplary embodiment, in the first position of the pad conditioning disk, the first region is recessed and the cutting elements of the second region contact the polishing pad, and in the second position, the first region protrudes from the second region in a direction toward the polishing pad and the cutting elements of the first region contact the polishing pad.

In an exemplary embodiment, the pad conditioning disk is coupled to a pad conditioner arm of the chemical mechanical polishing tool by a movable coupling, and the actuator causes independent movement between the first zone and the at least one other zone.

In an exemplary embodiment, the first zone is coupled to a pad conditioner arm of a chemical mechanical polishing tool by a first movable coupling, and the second zone is coupled to the pad conditioner arm by a second movable coupling. At least one of the first movable connections is actuated along the Z-axis to cause vertically independent movement of the first zone relative to the second zone, and the second movable connection is actuated along the Z-axis to cause vertically independent movement of the second zone relative to the first zone.

In an exemplary embodiment, the plurality of regions are at least one of: circular, annular, radial pie, spiral ribs, rectangular or triangular cutting areas (cutoes), and dies.

Another aspect relates to a chemical mechanical polishing tool, comprising: a polishing pad disposed on the platen, the polishing pad configured for polishing a substrate; a slurry delivery arm configured to deliver a slurry during pad conditioning; and a dresser assembly, the dresser assembly comprising: a pad conditioner arm coupled to a machine base of the chemical mechanical polishing tool, and a pad conditioning disk coupled to the pad conditioner arm, the pad conditioning disk having at least two zones that are activated with respect to each other to selectively engage the polishing pad.

In an exemplary embodiment, the at least two regions each comprise cutting elements that are the same or different in shape, size, distribution, density, and structure.

In an exemplary embodiment, a chemical mechanical polishing tool includes elements that activate and deactivate zone transitions.

In an exemplary embodiment, the pad conditioner arm includes two or more independent mechanisms connected to respective areas of the pad conditioning assembly.

Another aspect relates to a method for conditioning a polishing pad during chemical mechanical polishing, the method comprising: selectively activating selected regions of a pad conditioning disk having a plurality of regions, each region of the plurality of regions having cutting elements for conditioning a polishing pad, wherein the selection of the region for conditioning a polishing pad depends on a plurality of factors, and applying a downforce to the pad conditioning disk such that the cutting elements of the selected regions are in contact with the polishing pad, but the cutting elements of the other regions are not engaged with the polishing pad.

In an exemplary embodiment, the plurality of factors include a polishing recipe, a polishing project, a time of use of the chemical mechanical polishing tool, an interval of a plurality of wafers polished by the chemical mechanical polishing tool, a defined schedule, an optimal surface porosity of the polishing pad, and feedback from the dynamic feedback system.

In an exemplary embodiment, the factor is feedback from a dynamic feedback system that includes a property of the wafer, friction between the wafer and the polishing pad, and/or a roughness measurement of the polishing pad.

In an exemplary embodiment, the factor selected for conditioning a region of a polishing pad is the type of conditioning, which is either an in-situ conditioning period or an ex-situ conditioning period, further wherein during ex-situ conditioning, cutting elements of a selected region are engaged with the polishing pad while cutting elements of another region are disengaged from the polishing pad, and during in-situ conditioning, cutting elements of a selected region are disengaged from the polishing pad while cutting elements of another region are engaged with the polishing pad.

In an exemplary embodiment, the factor selected for conditioning the area of the polishing pad is whether the chemical mechanical polishing process is in a break-in phase or a wafer processing phase, further wherein during the break-in phase, the cutting elements of the selected area are engaged with the polishing pad and the cutting elements of the other area are disengaged from the polishing pad, and during the wafer processing phase, the cutting elements of the selected area are disengaged from the polishing pad and the cutting elements of the other area are engaged with the polishing pad.

In an exemplary embodiment, the factor selected for conditioning the area of the polishing pad is the type of conditioning, which is either in-situ conditioning or ex-situ conditioning.

In an exemplary embodiment, different areas of the pad conditioning disk are selectively activated based on a change in one or more of the plurality of factors. Selectively activating the different zones includes actuating a movable connection of the pad conditioner arm to adjust a position of the selected zone relative to the different zones.

The foregoing and other features of construction and operation will be more readily understood and appreciated from the following detailed disclosure, taken in conjunction with the accompanying drawings.

Drawings

Some embodiments will be described in detail with reference to the following drawings, wherein like reference numerals represent like elements, and wherein:

FIG. 1A shows a schematic top view of a CMP system according to an embodiment of the invention;

FIG. 1B shows a cross-sectional view of the CMP system of FIG. 1A in accordance with an embodiment of the present invention;

FIG. 2 shows a schematic diagram of a pad conditioning disk having multiple regions that selectively engage a polishing pad in a first position in accordance with an embodiment of the present invention;

FIG. 3 shows a schematic diagram of a pad conditioning disk having multiple zones that selectively engage a polishing pad in a second position in accordance with an embodiment of the present invention;

FIG. 4 shows a schematic diagram of a pad conditioning disk having multiple regions with different types of cutting elements, in accordance with an embodiment of the present invention;

FIG. 5 illustrates a schematic diagram of a pad conditioning disk having multiple regions with different types of cutting elements having changed positions compared to FIG. 4 in accordance with an embodiment of the present invention;

FIG. 6 illustrates a perspective view of a first position of a pad conditioning disk having concentric zones in accordance with an embodiment of the present invention;

FIG. 7 illustrates a bottom view of the pad conditioning disk of FIG. 6 in accordance with an embodiment of the present invention;

FIG. 8 illustrates a side view of the pad conditioning disk of FIG. 6 in accordance with an embodiment of the present invention;

FIG. 9 illustrates a cross-sectional view taken along line A-A of FIG. 7, in accordance with an embodiment of the present invention;

FIG. 10 illustrates a perspective view of a second position of the pad conditioning disk of FIG. 6 in accordance with an embodiment of the present invention;

FIG. 11 illustrates a bottom view of the pad conditioning disk of FIG. 10 in accordance with an embodiment of the present invention;

FIG. 12 illustrates a side view of the pad conditioning disk of FIG. 10 in accordance with an embodiment of the present invention;

FIG. 13 illustrates a cross-sectional view taken along line A-A of FIG. 11, in accordance with an embodiment of the present invention;

FIG. 14 shows a schematic view of a pad conditioning disk operatively connected to a pad conditioner arm in a first position in accordance with an embodiment of the present invention;

FIG. 15 shows a top view of FIG. 14 in accordance with an embodiment of the present invention;

FIG. 16 shows a schematic view of a pad conditioning disk operatively connected to a pad conditioner arm in a second position in accordance with an embodiment of the present invention;

FIG. 17 shows a schematic view of a pad conditioning disk operatively connected to a pad conditioner arm in a first position in accordance with an embodiment of the present invention;

FIG. 18 shows a top view of FIG. 17 in accordance with an embodiment of the present invention;

FIG. 19 shows a schematic view of a pad conditioning disk operatively connected to a pad conditioner arm in a second position in accordance with an embodiment of the present invention;

FIG. 20 illustrates a first configuration of a pad conditioning disk in accordance with an embodiment of the present invention;

FIG. 21 illustrates a second configuration of a pad conditioning disk in accordance with an embodiment of the present invention;

FIG. 22 illustrates a third configuration of a pad conditioning disk in accordance with an embodiment of the present invention;

FIG. 23 illustrates a fourth configuration of a pad conditioning disk in accordance with an embodiment of the present invention; and

fig. 24 illustrates a CMP tool utilizing a pad conditioning disk in accordance with an embodiment of the present invention.

Detailed Description

A detailed description of embodiments of the disclosed apparatus and methods, as described below, is given herein by way of illustration and not limitation with reference to the accompanying drawings. While certain embodiments have been illustrated and described in detail, it should be understood that various changes and modifications could be made therein without departing from the scope of the appended claims. The scope of the present disclosure is by no means limited to the number, materials, shapes, relative arrangements, etc., of constituent components, and is disclosed only as an example of an embodiment of the present disclosure.

As a prelude to the detailed description, it should be noted that, as used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

In brief overview, a pad conditioning disk is part of a CMP tool for establishing, maintaining, and restoring optimal surface porosity to a polishing pad used in a CMP process. There is a need for a polishing pad conditioning disk that performs a number of tasks on the polishing pad surface, including establishing a polishing surface with openings and uniform contact areas, efficiently removing polishing byproducts from the polishing pad surface, regenerating fresh surfaces after polishing, maintaining a consistent polishing pad surface throughout the useful life of the polishing pad, and avoiding the generation of large polishing pad fragments. To accomplish these tasks, the cutting elements of the pad conditioning disk, such as diamonds, cut through the surface of the polishing pad. The diamond selected for use as a conditioning tooth of the pad plays a critical role in defining the pad properties that in turn determine the wafer polishing properties such as removal rate, uniformity, dishing, erosion, defects, performance stability, etc. The diamond is selected according to the application, and is selected based on the size of the diamond, the orientation of the diamond, and the cutting angle of the diamond, such as the crystal shape (e.g., sharp and massive) of the diamond. Further considerations include leveling the diamond tips to uniformly expose the diamonds to the polishing pad, diamond density, and other configuration parameters.

Moreover, over time, the cutting edges of the diamond teeth of the pad conditioning disk wear, which results in replacement of the pad conditioning disk; although the polishing pad does not exceed its useful life completely, it is typically replaced along with the pad conditioning disk. In addition to the expense of new polishing pads and new pad conditioning disks, there are significant costs associated with the unavailability of CMP tools, as well as the cost of re-commissioning the CMP tools with new components.

Conventional pad conditioning disks include a single area of diamond teeth that move up and down as a unit. For example, all of the diamonds of a pad conditioner disk are bonded to an underlying layer, which acts as a unit in terms of interaction with the polishing pad. Not all diamonds can effectively bond to the polishing pad. Those in the relatively protruding position are engaged and wear out over time. At the same time, those diamonds that are in a relatively concave position do not effectively engage the pad surface and do not wear away over time. However, since all the diamonds are bonded into one piece, when the cutting edges of those protruding diamonds wear, the entire piece needs to be replaced.

Furthermore, conventional pad conditioning disks are largely limited to the same type of diamond due to the single area design. In many cases, CMP has multiple functional requirements for the pad conditioning process. For example, it may be desirable to efficiently create a surface texture and then maintain it. Different types of diamond may be preferred for creating surface texture and for maintaining the surface. In this case, limited to having only one type of diamond, conventional pad conditioning disks must use a compromise type of diamond to meet both functional requirements. As a result, CMP performance is compromised.

Therefore, it is desirable for the pad conditioning disk to produce and maintain the optimum surface porosity of the polishing pad for as long as possible. A pad conditioning disk according to an embodiment of the present invention includes a plurality of zones that are individually activated such that some diamond teeth are retained while other diamond teeth are used to condition a polishing pad. And unlike conventional disks, the retained diamonds can be activated late in the pad conditioning disk's useful life to maintain consistent cutting performance throughout the pad conditioning disk's useful life. In this manner, the aging of the diamonds, and thus the diamond disks, can be controlled and/or programmed to extend the life of the pad conditioning disks and, thus, the polishing pads.

Moreover, the multiple regions may include different types of diamonds in a single pad conditioning disk to increase functionality and effective pad surface engineering. For example, some type of sharp diamond may be used for the purpose of creating a desired surface texture, and some type of soft diamond (mil diamond) may be used for maintenance purposes once the surface texture is created. Switching between diamond types of a single pad conditioning disk is accomplished by relative motion between regions of the pad conditioning disk. Thus, a pad conditioning disk in accordance with an embodiment of the present invention has multiple diamond regions within the same pad conditioning disk to provide dynamic control over the polishing pad surface engineering, to achieve improved CMP process performance (e.g., fewer defects due to improved dishing/erosion), and to extend the useful life of the pad conditioning disk and other components of the CMP tool.

Referring now to the drawings, FIGS. 1A and 1B show a top schematic view and a cross-sectional view, respectively, of a CMP system 10 according to an embodiment of the present invention. The CMP system 10 is used for a CMP process. The CMP system 10 includes a slurry delivery arm 11, the delivery arm 11 configured to deliver a slurry 12 during polishing. Polishing liquid 12 may comprise an abrasive-containing polishing slurry, or may comprise an abrasive-free liquid, which may be reactive. The polishing pad 13 is disposed on the platen 14, and is configured to polish a substrate (e.g., a silicon wafer). The platen 14 is utilized to rotate the polishing pad 13 during processing so that the polishing pad 13 planarizes or polishes the surface of a substrate placed on the polishing pad 13. The polishing pad 13 is a consumable having a polishing surface, and may be fixed to the platen 14. The substrate is held by a polishing head 15 that rotatably contacts the substrate during processing. The polishing head 15 optionally includes a retaining ring that prevents the substrate from moving out from under the polishing head 15 during polishing. The CMP system 10 further includes a conditioner assembly including a pad conditioning disk 100 operatively connected to a pad conditioner arm 17 via a shaft 16; the pad conditioner arm 17 is attached to the machine base of the chemical mechanical polishing tool. The shaft 16 is disposed through the machine base of the CMP tool 10. The pad conditioner arm 16 may rotate about an axis perpendicular to the machine base. In an exemplary embodiment, rotation is facilitated by a bearing between the machine base 130 and the pad conditioner arm, such that the pad conditioner arm 16 rotates the pad conditioning disk 100. The disc 100 may further rotate at a rotational speed. A downward force is applied to urge the pad conditioning disk 100 against the polishing pad 13.

Pad conditioning disk 100 includes a plurality of zones that include cutting elements that selectively engage polishing pad 113 based on the positioning of the plurality of zones. The regions may be activated independently and/or individually relative to each other to selectively engage the polishing pad 13. For example, the diamonds on the pad conditioning disk 100 are grouped into two or more regions. Fig. 2 shows a schematic diagram of a pad conditioning disk 100 having multiple zones that selectively engage a polishing pad 13 in a first position in accordance with an embodiment of the present invention. In the illustrated embodiment, pad conditioning disk 100 includes a first region 1 having cutting elements 3 and a separate second region 2 having cutting elements 4. The

cutting elements

3, 4 of the first region 1 and the second region 2 are identical here. The

cutting elements

3, 4 are intended to cut through the polishing pad 13 to restore and/or maintain a desired/optimal surface porosity of the polishing pad 13, as previously described. The

cutting elements

3, 4 are in most cases diamond, but may also be other cutting elements, such as SiC, SiO₂Ceramic materials, diamond-like films, and the like. In addition, the cutting elements may also include or be replaced by brushes or other contact mechanisms that may be used to help clean and maintain the pad surface. In the first position shown in fig. 2, the cutting elements 3 associated with the first zone 1 are engaged with the polishing pad 13, while the cutting elements 4 associated with the second zone 2 are not engaged with the polishing pad 13. Thus, the cutting elements 4 remain because the cutting elements 4 are not mechanically engaged with the surface of the polishing pad 13.

Fig. 3 shows a schematic diagram of a pad conditioning disk 100 having multiple zones that selectively engage a polishing pad 13 in a second position in accordance with an embodiment of the present invention. In the second position shown in fig. 3, the positions of the first and second regions 1, 2 have changed, the cutting elements 4 associated with the second region 2 now engage the polishing pad 13, and the cutting elements 3 associated with the first region 3 now do not engage the polishing pad 13. Thus, the cutting elements 3 are at least temporarily retained, since the cutting elements 3 are now not mechanically engaged with the surface of the polishing pad 13. Fig. 3 also shows a situation in which the cutting edges of the cutting elements 3 are no longer effective in maintaining the desired cutting performance, so that the second region 2 is activated to bring the cutting elements 4 into active engagement with the polishing pad 13, while the first region 1 is moved away from the polishing pad 13 so that the cutting elements 3 are no longer in engagement with the polishing pad 13.

Accordingly, an exemplary embodiment of a pad conditioning disk 100 includes a plurality of regions 1, 2, each of which includes cutting

elements

3, 4 that selectively engage a polishing pad 13 based on the positioning of the plurality of regions 1, 2. When the first region 1 is placed closer to the polishing pad 13 than the second region 2, the cutting elements 3 engage the polishing pad 13, as shown in fig. 2. When the second region 2 is placed closer to the polishing pad 13 than the first region 1, the cutting elements 4 engage the polishing pad 13. Since each zone 1, 2 can be moved independently with respect to each other, a change of position between the zones 1, 2 can be achieved.

Each zone may be activated in various ways to facilitate movement of the zone. In an exemplary embodiment, one or more zones are activated by pushing them down in the Z-axis while pulling them up on other zones. If desired, one or more of the deactivated areas are lifted from the polishing pad to avoid engaging the polishing pad while other areas are actively conditioning the polishing pad. In addition, different downward forces may be applied to different regions if desired. Various mechanisms may be used to activate the various zones. The activation mechanism may be electrical, mechanical or electromechanical. For example, the region may be electrically actuated via a motor, battery, shape memory actuator such as nitinol, solenoid, magnet, one or more servo motors, one or more stepper motors, electroactive polymer, piezoelectric, and switch, among others. The region may be mechanically actuated via springs, pneumatic elements, screws, hydraulic elements, pulleys, gears, lights, balls, detents, and the like. A combination of electrical and mechanical mechanisms may also be used. Further, the pad conditioning disk having multiple zones may be a stand-alone unit with its own activation/deactivation mechanism or controller, or alternatively, the pad conditioning disk may be connected to the CMP system 10 with activation/deactivation being communicated through the CMP system 10.

Referring again to fig. 2-3, the connecting means 5 operatively connects the plurality of zones 1, 2 and facilitates movement between the plurality of zones 1, 2. The connection means 5 are knobs, axles, hinges, pivot joints, levers, wheels, shafts, cylinders or similar rotating means allowing to activate certain areas and to deactivate others. At a given time, the connecting means 5 are rotated in a first direction which activates some zones, while others are waiting in line. For example, when the coupling device 5 is rotated in a first direction, the first region 1 is activated (e.g., lowered) to engage the cutting elements 3 with the polishing pad 13 to cut into the pad for active conditioning, while the second region 2 is deactivated (e.g., lifted) to remove the cutting elements 4 from the polishing pad 13. Conversely, when the linkage 5 is rotated in a second direction opposite the first direction, the second region 2 is activated (e.g., lowered) to engage the cutting elements 4 with the polishing pad 13 to cut into the pad for active conditioning, while the first region 1 is deactivated (e.g., lifted) to remove the cutting elements 3 from the polishing pad 13.

According to further embodiments, pad conditioning disk 100 optionally includes multiple regions with different types of cutting elements to increase functionality. Fig. 4 shows a schematic diagram of a pad conditioning disk 100 having multiple zones with different types of cutting elements 3', 4' in accordance with an embodiment of the present invention. In the illustrated embodiment, pad conditioning disk 100 includes a first region 1 having cutting elements 3 'and a separate second region 2 having cutting elements 4'. The cutting elements 3', 4' of the first region 1 and of the second region 2 are not identical. Cutting element 3' may have a different size than cutting element 4' and/or may have a different orientation and/or cutting angle than cutting element 4 '. For example, the cutting elements 3 'mounted on the first region 1 are block diamonds, while the cutting elements 4' mounted on the second region 2 are sharp diamonds. In the first position shown in fig. 4, the sharp diamonds engage the polishing pad 13, while the bulk diamonds do not engage the polishing pad 13. Thus, bulk diamond is retained or intentionally unused during a particular application.

FIG. 5 shows a schematic of a pad conditioning disk having multiple regions with different types of cutting elements in different positions than FIG. 4 in accordance with an embodiment of the present invention. In the second position shown in fig. 5, the positions of the first region 1 and the second region 2 have changed, the block diamonds now engaging the polishing pad 13, and the sharp diamonds now not engaging the polishing pad 13. Thus, as the requirements of the CMP process have changed, the sharp diamond is retained or intentionally not used during certain applications.

Pad conditioning disk 100 having multiple regions and multiple different types of cutting elements imparts some desired effect. This mixed use of different types of cutting elements on the same pad conditioning disk 100 provides the potential to combine the advantages of different types of cutting elements that would otherwise be unavailable. For example, a sharp diamond may be mounted to one region for aggressive region activation and a bulk diamond may be mounted to another region for mild region activation. During ex-situ conditioning, during the time period when the wafer is not on the polishing pad, the aggressive regions are activated to make deeper cuts with sharp diamond teeth and effectively restore the polishing pad; large fragments of the polishing pad resulting from activation of the aggressive regions may then be flushed from the polishing pad surface without contacting the wafer. During in situ conditioning, when the wafer is simultaneously polished, the mild zones are activated to provide a gentle cutting effect with the bulk diamond teeth, which helps maintain a flat and consistent surface. The mild zone activation also helps to achieve better dishing/erosion performance while avoiding the possibility of scratching the wafer due to large polishing pad debris.

Various combinations of cutting element types may be used for each zone. For example, the first region may use conventional diamond grit, while the second region may use Chemical Vapor Deposition (CVD) diamond. More than two different types of cutting elements may be used in a single pad conditioning disk. In a pad conditioning disk having four different zones, four different types of cutting elements may be used. Alternatively, if the pad conditioning disk has four regions, two different types of cutting elements may be used; two regions may have the same type of cutting elements and the remaining two regions may have the same type of cutting elements.

Turning now to exemplary embodiments of pad conditioning disks utilizing embodiments in accordance with the present invention. Fig. 6 illustrates a perspective view of a first position of a pad conditioning disk 200 having concentric regions in accordance with an embodiment of the present invention. Fig. 7 illustrates a bottom view of the pad conditioning disk 200 of fig. 6 in accordance with an embodiment of the present invention. Fig. 8 illustrates a side view of the pad conditioning disk 200 of fig. 6 in accordance with an embodiment of the present invention. FIG. 9 illustrates a cross-sectional view taken along line A-A of FIG. 7, in accordance with an embodiment of the present invention. As shown in fig. 6-9, pad conditioning disk 200 includes an outer region 201 and an inner region 202. The inner region 202 is at least slightly recessed relative to the outer region 201; the inner region 202 is located within a blank area surrounded by the inner diameter edge surface of the outer region 201. In this first position, the cutting elements of the outer region 201 engage the polishing pad, while the cutting elements of the inner region 202 do not engage the polishing pad.

Fig. 10 illustrates a perspective view of a second position of the pad conditioning disk 200 of fig. 6 in accordance with an embodiment of the present invention. Fig. 11 illustrates a bottom view of the pad conditioning disk 200 of fig. 10 in accordance with an embodiment of the present invention. Fig. 12 illustrates a side view of the pad conditioning disk 200 of fig. 10 in accordance with an embodiment of the present invention. FIG. 13 illustrates a cross-sectional view taken along line A-A of FIG. 11, in accordance with an embodiment of the present invention. As shown in fig. 10-13, the inner region 202 is now closer to the polishing pad such that in this second position, the cutting elements of the inner region 202 engage the polishing pad while the cutting elements of the outer region 201 do not engage the polishing pad.

The connection means 205 facilitate the movement of the outer region 201 relative to the inner region 202 and vice versa. The connection means 205 is a threaded connection between the outer region 201 and the inner region 202. In the exemplary embodiment, outer region 201 includes female threads that are circumferentially disposed along an inner surface of outer region 201, and inner region 202 includes corresponding male threads that mate with the female threads of outer region 201. In another embodiment, the outer region 201 may include male threads and the inner region 202 may include female threads. Threading of one or both of the

regions

201, 202 in either a clockwise or counterclockwise direction effects relative movement of the

regions

201, 202. Thus, if the inner region 202 is activated (e.g., the cutting elements of the inner region 202 are needed at a given time), the inner region 202 is pulled forward toward the polishing pad, or the outer region 201 is pulled apart, or a combination of forward and backward movements. Fig. 9 and 13 best illustrate the relative movement between the outer region 201 and the inner region 202 due to the connection means 205. In an alternative embodiment, the connection means 205 is formed by a single helical groove as a thread in a similar position to the thread in the outer region 201 or inner region 202 and a lip/tongue/protrusion fitted within the groove and running circumferentially around the groove to enable relative vertical movement between the outer region 201 and inner region 202.

Continuing with the pad conditioning disk 200, fig. 14-16 illustrate an exemplary embodiment of activating one of the plurality of

zones

201, 202 to change the position of the zone 201 relative to the zone 202. Fig. 14 shows a schematic view of a pad conditioning disk 200 operatively connected to the pad conditioner arm 16 in a first position, in accordance with an embodiment of the present invention. The cutting elements of the outer region 201 are attached to the substrate 210 by fasteners 207. The bottom layer 210 is attached to the pad conditioner arm 16 by a movable attachment 19, as shown in fig. 15. The movable attachment 19 is a shaft fixedly attached to the lower and/or outer region 201 and movably attached to the pad conditioner arm 16. As shown in fig. 15, the location of the connection 19a is for illustration only, and may be placed in a different location, such as in the center of the disk, and other mechanical configurations may be used to accomplish this connection. In the first position shown by fig. 14, the inner region 202 is recessed between the rings of the outer region 201 such that the cutting elements of the inner region 202 will not engage the polishing pad, while the cutting elements of the outer region 201 will engage the polishing pad. Fig. 16 shows a schematic view of a pad conditioning disk 200 operatively connected to the pad conditioner arm 16 in a second position, in accordance with an embodiment of the present invention. In the second position shown by fig. 16, the relative position between the outer region 201 and the inner region 202 has changed; the inner region 202 protrudes from the outer region 201. In this position, the cutting elements of the inner region 202 will now engage the polishing pad, while the cutting elements of the outer region 201 will now no longer engage the polishing pad. The movement of the

regions

201, 202 relative to each other is achieved by a threaded connection therebetween, as described previously with respect to the connection means 205. The motor rotates movable connection 19, which in turn rotates substrate 110, and thus outer region 201, which is secured to substrate 210. Rotation of the outer region 201 causes the inner region 202 to move up and down depending on the direction of rotation of the threaded connection.

Fig. 17-19 illustrate another exemplary embodiment of activating one of the plurality of

regions

201, 202 to change the position of the region 201 relative to the region 202. Fig. 17 shows a schematic view of a pad conditioning disk 200 operatively connected to the pad conditioner arm 16 in a first position, in accordance with an embodiment of the present invention. The cutting elements of the outer region 201 are attached to the substrate 210 by fasteners 207, while the cutting elements of the inner region 202 are attached to a separate substrate 211 by fasteners 208. The bottom layers 210, 211 are attached to the pad conditioner arm 16 by

separate attachments

19a and 19b, respectively. The

movable couplings

19a, 19b are shafts fixedly connected to the respective base layers and movably connected to the pad conditioner arm 16, as shown in fig. 18. As shown in fig. 18, the location of the

connectors

19a, 19b is for illustration only, and may be placed in different locations, and other mechanical configurations may be used to accomplish the connection. In the first position shown by fig. 17, the inner region 202 is recessed between the rings of the outer region 201 such that the cutting elements of the inner region 202 will not engage the polishing pad, while the cutting elements of the outer region 201 will engage the polishing pad. Fig. 19 shows a schematic view of a pad conditioning disk 200 operatively connected to the pad conditioner arm 16 in a second position, in accordance with an embodiment of the present invention. In the second position shown by fig. 19, the relative position between the outer region 201 and the inner region 202 has changed; the inner region 202 protrudes from the outer region 201. In this position, the cutting elements of the inner region 202 will now engage the polishing pad, while the cutting elements of the outer region 201 will now no longer engage the polishing pad. Movement of the

zones

201, 202 relative to each other is achieved by actuating one or both of the

movable connections

19a, 19b along the Z-axis. Actuators, such as motors, pneumatic actuators, hydraulic actuators, mechanical actuators, and the like, actuate one or both of the

movable links

19a, 19b along the Z-axis to change the position of the

zones

201, 202. For example, movable connector 19a is actuated in an upward direction to raise outer region 201 a distance, while movable connector 19b is actuated in a downward direction to lower inner region 202. In other examples, only movable connection 19a or only movable connection 19b is actuated to actuate

regions

201, 202 to a desired position or configuration.

Various regions of a pad conditioning disk according to embodiments of the present invention may be designed in various geometries and configurations. For example, these areas may be concentric rings, radial biscuits, spiral bars and dies (dies) that comprise circular pad conditioning discs. Fig. 20-23 show only a few of the possible configurations of the plurality of zones. Fig. 20 shows a pad conditioning disk 300 according to an embodiment of the invention. The pad conditioning disk 300 comprises two

separate areas

301, 302, which are concentrically arranged as an outer area 301 and an inner area 302. Fig. 21 shows a pad conditioning disk 400 according to an embodiment of the invention. The pad conditioning disk 400 comprises three

zones

401, 402, 403. The

regions

401 and 403 are arranged along the outer ring of the pad conditioning disk 400 as a radial pie-shaped cross-section. The area 402 is arranged as a central portion within the outer ring of the pad conditioning disk 400. Fig. 22 shows a pad conditioning disk 500 according to an embodiment of the invention. The pad conditioning disk 500 includes a total of sixteen regions arranged circumferentially around the pad conditioning disk 500. The total sixteen zones are comprised of four different types of cutting elements labeled 501, 502, 503, and 504. Although a total of sixteen zones are shown, any number of zones may be used in a similar configuration. Fig. 23 shows a pad conditioning disk 600 according to an embodiment of the invention. The pad conditioning disk 600 includes a total of thirty-two areas arranged in rows and columns on the pad conditioning disk 600. The thirty-two zones are comprised of five different types of cutting elements, labeled 601, 602, 603, 604, and 605. Although a total of thirty-two zones are shown, any number of zones may be used in a similar configuration. Furthermore, O-rings and/or other insulation means are optionally provided between the zones to avoid the accumulation of chemicals/slurries/byproducts.

With continued reference to the figures, FIG. 24 illustrates a CMP tool 1000 utilizing a pad conditioning disk in accordance with an embodiment of the present invention. The CMP tool 1000 includes a polisher having a machine base 130, a slurry delivery arm 190, a polishing pad 104 disposed on a platen 102, a polishing head 106, a conditioner assembly 122, and a controller 152. The machine base 130 supports the platen 102, slurry delivery arm 190, and dresser assembly 122. The platen 102 supports a polishing head 106. The polishing head 106 may be rotated by a motor 120 to rotate the substrate 118 about a central axis D of the polishing head 106 against the polishing pad 104. The sensor 148 may be utilized to obtain the amount of force required to rotate the substrate 118 against the polishing pad 104.

The platen 102 is utilized to rotate the polishing pad 104 during processing so that the polishing pad 104 planarizes ("polishes") the surface of a substrate 118 placed on the pad 104. The polishing pad 104 is a consumable having a polishing surface and may be secured to the platen 102. A motor 112 coupled to the platen 102 by a shaft 114 rotates the platen 102 and polishing pad 104. The polishing pad 104 is moved relative to a substrate 118 held in the polishing head 106 by a motor 112. In the illustrated embodiment, the motor 112 rotates the platen 102 in the X-Z plane about a central axis a that is perpendicular to the platen 102. The sensor 150 can be utilized to obtain the amount of force required to rotate the platen 102 and polishing pad 104 relative to the substrate 118 and/or the dresser assembly 122.

The slurry delivery arm 190 provides a slurry to the surface of the polishing pad 104 during polishing. The dresser assembly 122 generally includes a dresser head 108, a shaft 126, and an arm 128. The shaft 126 and arm 128 support the conditioning head 108 above the platen 102. The conditioning head 108 retains a conditioning disk according to an embodiment of the present invention that is selectively placed into engagement with the polishing pad 104 to condition the surface of the polishing pad 104. The shaft 126 is disposed through the machine base 130 of the CMP tool 1000. The shaft 126 may rotate about an axis B perpendicular to the machine base 130, which rotation is facilitated by a bearing 132 between the machine base 130 and the shaft 126, causing the arm 128 to rotate the conditioning head 108. In one embodiment, a sweep actuator (sweep activator) 144 coupled to the shaft 126 may rotate the shaft 126 to push the arm 128 to scan the conditioning head 108 across the polishing pad 104. The conditioning head 108 rotates the conditioning disk about an axis C that is generally disposed through the conditioning disk. In one embodiment, the conditioning disk is rotated relative to the polishing pad 104 using a motor 134. In one embodiment, the motor 134 is disposed in a housing 136 at the distal end of the arm 128.

The conditioning disk is urged toward the polishing pad 104 by a downward force actuator 140. The downward force actuator 140 is configured to selectively set the force exerted by the conditioning disk 124 on the polishing pad 104. In one embodiment, the downward force actuator 140 may be disposed between the arm 128 and the shaft 126, or at other suitable locations. The amount of downforce indicative of the conditioning disk downforce being applied to polishing pad 104 is detected by downforce sensor 142. In one embodiment, the downward force sensor 142 may be disposed coaxially with the downward force actuator 140, or may be placed at other suitable locations.

Generally, the controller 152 is used to control one or more components and processes performed in the CMP tool 1000. The controller 152 may be coupled to the CMP tool 1000 at various points to send and receive signals to and from various components. For example, the controller may be connected to a dynamic pad conditioning disk feedback system. The dynamic feedback system collects readings of the pad roughness and is transmitted by the central processing unit 154 to the server to calculate whether additional conditioning of the polishing pad is required. The controller 152 may make adjustments based on calculations received from the server. The dynamic feedback system may also capture a high resolution optical image of the polishing pad surface to analyze the pad's roughness by the server. The dynamic feedback system may also be used to measure the torque and friction or other components of the CMP tool 1000. In addition, a feedback system can be used to adjust downforce and/or adjust the ratio of aggressive area to mild area usage for pad conditioning.

The controller 152 is generally designed to facilitate control and automation of the CMP tool 1000, and typically includes a Central Processing Unit (CPU) 154, memory 156, and support circuits (or I/O) 158. The CPU 154 may be one of any form of computer processor used in an industrial setting for controlling various system functions, substrate movement, chamber processing, process timing and support hardware (e.g., sensors, robots, motors, timing equipment, etc.) and monitoring processes (e.g., chemical concentrations, process variables, chamber processing times, I/O signals, etc.). Memory 156 is connected to the CPU 154 and may be one or more of readily available memory such as Random Access Memory (RAM), Read Only Memory (ROM), floppy disk, hard disk, or any other form of digital storage, local or remote. Software instructions and data may be encoded and stored in memory to instruct CPU 154. Support circuits 158 are also connected to the CPU 154 for supporting the processor in a conventional manner. The support circuits 158 may include caches, power supplies, clock circuits, input/output circuits, subsystems, and the like. A program or computer instructions readable by the controller 152 determines which tasks can be performed on the substrate. Preferably, the program is software readable by controller 152 that includes code for performing tasks related to monitoring, executing, and controlling the movement, support, and/or positioning of a substrate in polisher 100. In one embodiment, controller 152 is used to control the robotic equipment to control strategic movements, scheduling and operation of polisher 100 so that the process can be repeated, to address queue timing issues and to prevent over-or under-processing of the substrate.

In addition, a pad conditioning disk according to an embodiment of the present invention is used to condition a polishing pad of a CMP tool. For example, a method for conditioning a polishing pad of a chemical mechanical polishing tool includes selectively activating selected areas of a pad conditioning disk having a plurality of areas. Each of the plurality of regions has cutting elements for conditioning the polishing pad. The selection of the area for conditioning the polishing pad depends on a number of factors. The plurality of factors include a polishing recipe, a polishing project, a time of use of the chemical mechanical polishing tool, a spacing of a plurality of wafers polished by the chemical mechanical polishing tool, an optimal surface porosity of the polishing pad, and the like.

For example, an initial region is selected for conditioning the polishing pad and activated accordingly, such that the cutting elements of the initial region will be used to condition the polishing pad. The initial region is selected based on the fact that: the CMP process is currently being performed ex situ, and when the wafer is not being polished on the polishing pad at the same time, the cutting elements of the initial zone are best suited for ex situ conditioning. Downward force (e.g., downforce) is applied to the pad conditioning disk such that the initially selected regions of the cutting elements engage the polishing pad, but other regions of the cutting elements do not engage the polishing pad. If the CMP process is changed to in-situ conditioning, a new different area is selectively activated based on the change from ex-situ conditioning to in-situ conditioning while the wafer is polished on the polishing pad at the same time. The combination of ex-situ and in-situ produces a desirable pad surface texture, minimizes pad conditioning by-products, and avoids excessive pad wear.

As another example, an initial area is selected for conditioning the polishing pad and activated accordingly, such that the cutting elements of the initial area will be used to condition the polishing pad. The initial area is selected to condition the polishing pad to accommodate the number of "x" wafers polished by the CMP tool. Downward force (e.g., downforce) is applied to the pad conditioning disk such that the initially selected regions of the cutting elements engage the polishing pad, but other regions of the cutting elements do not engage the polishing pad, thereby retaining those cutting elements. After "x" wafers are polished by the CMP tool, a new, different area is selectively activated to condition the polishing pad for another "x" wafers. In this case, both regions have the same type of cutting element. In this manner, the cutting elements wear at different rates, and no pad conditioning disk change is required to obtain optimal performance with new cutting elements.

In another example, during a break-in period of a polishing pad that is new, used, or not actively used for a period of time, one region of the cutting element is activated by some type of diamond engaging the surface of the polishing pad to create the desired surface texture/porosity, while the other region is disengaged. During the process of actively using the polishing pad for wafer polishing, different regions are activated with certain different types of diamonds, while a first region of the diamond is disengaged to produce different types of pad surface texture/porosity (e.g., smooth and consistent) and with different sizes (e.g., finer) of cutting byproducts. During polishing, particularly during ex-situ conditioning, when a wafer is not being polished on the pad at the same time, one region of the diamond is activated by some type of diamond engaging the pad surface to produce the desired surface texture/porosity, with a certain size of cutting byproducts, while the other region is disengaged. During the polishing process, particularly during in situ conditioning, when wafers are simultaneously polished on the pad, different regions are activated with some different type of diamond, while a first region of the diamond is debonded to produce a different type of pad surface texture/porosity (e.g., smooth and consistent), and with different sizes (e.g., finer) of cutting byproducts. The combination of which produces the desired performance and avoids excessive wear.

Furthermore, the method may also be applied in a CMP process, where during the first part of the polishing process, a first region of diamond is activated by some type of diamond engaging the pad surface to produce the desired surface texture/porosity, while other regions are disengaged. During the second portion of polishing, a second region of diamonds is activated with a certain different type of diamond while the first region of diamonds is disengaged to create a different type of pad surface texture/porosity.

Further, different applications may be used to share the same platen. For example, if a first application is being used, a first region of diamonds is activated by engagement of certain types of diamonds with the pad surface to create the desired surface texture/porosity while other regions are disengaged. If a second application is being used, a second region of diamonds is activated by engagement of certain types of diamonds with the pad surface to create the desired surface texture/porosity while other regions are disengaged. If a third application is being used, a third region of diamonds is activated by engagement of certain types of diamonds with the pad surface to create the desired surface texture/porosity, while other regions are disengaged, and so on.

While the present disclosure has been described in conjunction with the specific embodiments outlined above, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, the preferred embodiments of the present disclosure as set forth above are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the invention as claimed in the appended claims. The claims provide coverage of the present invention and should not be limited to the specific examples provided herein.

Claims

1. A pad conditioning disk configured to condition a polishing pad of a chemical mechanical polishing tool, the pad conditioning disk comprising:

a plurality of regions comprising cutting elements that selectively engage the polishing pad based on positioning of the plurality of regions.

2. The pad conditioning disk of claim 1 wherein the plurality of zones are movable relative to each other such that cutting elements of a first zone of the plurality of zones engage the polishing pad during chemical mechanical polishing and cutting elements of a second zone of the plurality of zones do not engage the polishing pad.

3. The pad conditioning disk of claim 1 wherein the cutting elements are diamond or diamond-like films of the same or different shape, size, distribution, density and/or structure, or at least one cutting element is a brush.

4. The pad conditioning disk of claim 1 wherein a first region of the plurality of regions comprises particulate diamond having a shape, size, distribution, and density, and a second region of the plurality of regions comprises a Chemical Vapor Deposition (CVD) diamond film coated on a textured surface.

5. A chemical mechanical polishing tool comprising:

a polishing pad disposed on the platen, the polishing pad configured for polishing a substrate;

a slurry delivery arm configured to deliver a slurry during pad conditioning; and

a dresser assembly, the dresser assembly comprising:

a pad conditioner arm coupled to a machine base of the chemical mechanical polishing tool, an

A pad conditioning disk connected to the pad conditioner arm, the pad conditioning disk having at least two regions that are activated relative to each other for selective engagement with the polishing pad.

6. The chemical mechanical polishing tool of claim 5, wherein the chemical mechanical polishing tool comprises elements and mechanisms to activate and deactivate zone transitions.

7. A method for conditioning a polishing pad during chemical mechanical polishing, the method comprising:

selectively activating selected areas of a pad conditioning disk having a plurality of areas with cutting elements for conditioning the polishing pad, wherein the selection of the area for conditioning the polishing pad depends on one of a plurality of factors; and

applying a down force to the pad conditioning disk such that the selected regions of the cutting elements engage the polishing pad, but other regions of the cutting elements do not engage the polishing pad.

8. The method of claim 7, wherein the plurality of factors comprise a polishing recipe, a polishing project, a time of use of a chemical mechanical polishing tool, an interval of a plurality of wafers polished by the chemical mechanical polishing tool, a defined schedule, or feedback from a dynamic feedback system, further wherein the factors are feedback from the dynamic feedback system, the feedback comprising a property of the wafer, a friction between the wafer and the polishing pad, a roughness measurement of the polishing pad, and/or a porosity measurement of the polishing pad.

9. The method of claim 7, wherein the method further comprises:

selectively activating different regions of a pad conditioning disk based on a change in one or more of the plurality of factors, wherein the selectively activating different regions includes actuating a movable link of a pad conditioner arm to adjust a position of the selected region relative to the different regions.

10. The method of claim 7, wherein:

the factor for selecting a region for conditioning the polishing pad is a type of conditioning, which is either an in-situ conditioning period or an ex-situ conditioning period, further wherein during the ex-situ conditioning the cutting elements of the selected region are engaged with the polishing pad while the cutting elements of another region are disengaged from the polishing pad, and during the in-situ conditioning the cutting elements of the selected region are disengaged from the polishing pad while the cutting elements of the other region are engaged with the polishing pad; or

The factor for selecting the area for conditioning the polishing pad is whether the chemical mechanical polishing process is in a break-in phase or a wafer processing phase, further wherein during the break-in phase the selected area of cutting elements are engaged with the polishing pad and another area of cutting elements are disengaged from the polishing pad, and during the wafer processing phase the selected area of cutting elements are disengaged from the polishing pad and another area of cutting elements are engaged with the polishing pad.