TW202015861A - Multiple zone pad conditioning disk - Google Patents

Abstract

A pad conditioning disk configured to condition a polishing pad of a chemical mechanical polishing tool including a plurality of zones comprising cutting elements that selectively engage the polishing pad based on positioning of the plurality of zones, is provided. An associated chemical mechanical polishing (CMP) tool and method for conditioning a polishing pad during a chemical mechanical polishing process is also provided.

Description

Multi-zone pad trimming disc

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

Chemical mechanical polishing (CMP) or planarization is a polishing process used for silicon wafers and other substrates. This process uses the polishing liquid on the polishing pad and its chemical and abrasive agents, combined with chemical and mechanical effects, for Remove excess material from the surface and silicon wafers and other substrates with smooth and flat surfaces to obtain the required thickness. The polishing pads used for successful CMP require good surface porosity, and tend to lose surface porosity due to surface degradation over time. Polishing pad dressing discs are a key element of CMP technology used to establish, maintain, and recreate the excellent surface porosity of polishing pads.

An object of the present invention relates to a pad dressing disc configured to dress a polishing pad of a chemical mechanical polishing tool, which includes a plurality of areas including cutting that selectively engages the polishing pad based on the positioning of the plurality of areas element.

In an exemplary embodiment, the plurality of regions can move relative to each other.

In an exemplary embodiment, the plurality of regions can move relative to each other so that the cutting elements of the first region of the plurality of regions are in contact with the polishing pad during chemical mechanical polishing, while the second of the plurality of regions The cutting elements in the area are not in contact with the polishing pad.

In an exemplary embodiment, the first region of the plurality of regions includes granular diamond having a certain shape, size, distribution, and density, and the second region of the plurality of regions includes chemical gas coated on the textured surface Phase deposition (chemical vapor deposition, CVD) diamond film.

In an exemplary embodiment, the cutting elements in each region are diamond or diamond-like films with the same shape, size, distribution, density and structure, or the cutting elements in each region are different in shape, size, distribution, density and structure Diamond.

In an exemplary embodiment, the connection device is operably connected to 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 area is recessed, and the cutting elements of the second area contact the polishing pad, and in the second position, the first area is facing toward the polishing pad The direction protrudes from the second area, and the cutting elements of the first area contact the polishing pad.

In an exemplary embodiment, the pad dressing disc is connected to the pad dresser arm of the chemical mechanical polishing tool through a movable connection, and the actuator promotes independent movement between the first area and at least another area.

In an exemplary embodiment, the first area is connected to the pad conditioner arm of the chemical mechanical polishing tool through the first movable connection, and the second area is connected to the pad conditioner arm through the second movable connection. Actuate at least one of the first movable links along the Z axis to promote vertical independent movement of the first area relative to the second area, and actuate the second movable links along the Z axis to promote the second area relative to the first area Vertical independent movement.

In an exemplary embodiment, the plurality of regions are at least one of the following: circular, circular, radial pie-shaped, spiral ribs, rectangular or triangular cutouts, and dies.

Another object relates to a chemical mechanical polishing tool, which includes: a polishing pad placed on a platen, the polishing pad configured to polish a substrate; a polishing liquid conveying arm, the polishing liquid conveying arm configured to be placed on a pad Delivery of polishing fluid during the dressing process; and dresser elements including: pad dresser arms connected to the machine base of the chemical mechanical polishing tool, and pad dresser disks connected to the pad dresser arm, pad dresser disks There are at least two regions of phase that are activated with respect to each other to selectively engage the polishing pad.

In an exemplary embodiment, each of the at least two regions includes cutting elements having the same shape, size, distribution, density, and structure or different shapes, sizes, distribution, density, and structure.

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

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

Another object relates to a method for dressing a polishing pad during a chemical mechanical polishing process, the method comprising: selectively activating selected areas in a pad conditioning disk having a plurality of areas, each of the plurality of areas having Cutting elements for dressing polishing pads, where the selection of the area for dressing the polishing pad depends on a number of factors, as well as the application of downforce to the pad dressing disc to bring the cutting elements of the selected area into contact with the polishing pad, but the cutting of other areas The element does not engage the polishing pad.

In the exemplary embodiment, the plurality of factors include a polishing recipe, a polishing project, a usage time of a chemical mechanical polishing tool, an interval of a plurality of wafers polished by the chemical mechanical polishing tool, a defined plan table, and an excellent surface of the polishing pad Porosity and feedback from dynamic feedback systems.

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

In an exemplary embodiment, the factor for selecting the area for trimming the polishing pad is the type of trimming, and the type of trimming is the in-situ trimming period or the ex-situ trimming period. Further, during the ex-situ trimming, the selected area The cutting element is engaged with the polishing pad, while the cutting element in another area is disengaged from the polishing pad, and during in-situ dressing, the cutting element in the selected area is disengaged from the polishing pad, and the cutting element in the other area is engaged with the polishing pad.

In the exemplary embodiment, the factor for selecting the area for polishing the polishing pad is whether the chemical mechanical polishing process is in the run-in phase or wafer processing phase, further, wherein in the run-in phase, the cutting elements of the selected area are engaged with the polishing pad, and The cutting element in another area is detached from the polishing pad, and in the wafer processing stage, the cutting element in the selected area is detached from the polishing pad, and the cutting element in the other area is engaged with the polishing pad.

In an exemplary embodiment, the factor for selecting the area for trimming the polishing pad is the type of trimming, and the type of trimming is in-situ trimming or ex-situ trimming.

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

The foregoing and other features of construction and operation will be easier to understand and fully understand in light of the following detailed disclosure in conjunction with the drawings.

Cross-reference of related applications: This application requires the rights and priority of US Provisional Application No. 62/737,078, entitled "Pad Conditioning Disk with Multiple Zones", filed on September 26, 2018.

A detailed description of the embodiments of the disclosed apparatus and method as described below is given by way of example and not limitation with reference to the drawings. Although certain embodiments have been shown and described in detail, it should be understood that various changes and modifications may be made without departing from the scope of the appended patent applications. The scope of the present disclosure is by no means limited to the number, material, shape, relative arrangement, etc. of constituent parts, and is disclosed only as an example of an embodiment of the present disclosure.

As a preface to the detailed description, it should be noted that, as used in this specification and the appended patent application, the singular forms "a" and "the" include plural indicators unless the context clearly dictates otherwise.

Briefly summarized, the pad conditioning disk is part of the CMP tool and is used to establish, maintain and restore the excellent surface porosity of the polishing pad used in the CMP process. It is necessary to use polishing pad dressing discs to perform multiple tasks on the surface of the polishing pad, including establishing a polishing surface with openings and uniform contact areas, effectively removing polishing byproducts on the surface of the polishing pad, regenerating the new surface after polishing, and polishing the pad Maintain a consistent polishing pad surface throughout the entire life span and avoid the generation of large polishing pad fragments. To accomplish these tasks, the cutting elements of the pad conditioning disk, such as diamond, cut through the surface of the polishing pad. The diamond selected as the pad dressing tooth plays a vital role in defining the performance goals of the pad, and the performance of the pad determines the performance of the wafer polishing, such as removal rate, uniformity, depression, corrosion, defects, performance stability Wait. The diamond is selected according to the application, and the diamond 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 of the diamond (eg, sharp and bulk). Further considerations include leveling the diamond tip to expose the diamond uniformly to the polishing pad, diamond density, and other configuration parameters.

Moreover, over time, the cutting edges of the diamond teeth of the pad dressing disc wear out, which results in replacement of the pad dressing disc; although the polishing pad does not completely exceed its service life, it is typically replaced with the pad dressing disc. In addition to the cost of new polishing pads and new pad dressing discs, there are many significant costs associated with the unavailability of CMP tools, and the cost of putting CMP tools back into production with new components.

The conventional pad dressing disc includes a single area of diamond teeth that move up and down as a unit. For example, all diamonds of a pad conditioning disk are bonded to a bottom layer, which acts as a unit in terms of interaction with the polishing pad. Not all diamonds can be effectively bonded to polishing pads. Those in relatively protruding positions are engaged and wear out over time. At the same time, those diamonds in relatively recessed positions are not effectively engaged with the pad surface and will not wear out over time. However, since all diamonds are bonded into one part, when the cutting edges of those protruding diamonds wear out, the entire part needs to be replaced.

Furthermore, due to the single-zone design, the conventional pad dressing discs are largely limited to the same type of diamond. In many cases, CMP has multiple functional requirements for the pad finishing process. For example, you may need to effectively create surface textures and then maintain them. It may be preferred to use different types of diamonds for generating surface textures and for maintaining surfaces. In this case, limited to having only one type of diamond, conventional pad dressing discs must use a compromised type of diamond to meet two functional requirements. As a result, CMP performance is impaired.

Therefore, it is desirable that the pad conditioning discs produce and maintain a good surface porosity of the polishing pad as long as possible. The pad dressing disc according to an embodiment of the present invention includes multiple regions that are individually activated so that some diamond teeth are retained while other diamond teeth are used to dress the polishing pad. And unlike traditional disks, retained diamonds can be activated later in the life of the pad dressing disk to maintain consistent cutting performance throughout the life of the pad dressing disk. In this way, the aging of the diamond can be controlled and/or planned, so that the aging of the diamond disk can be controlled and/or planned to extend the life of the pad dressing disk and thus the life of the polishing pad.

Moreover, the multiple regions can include different types of diamonds in a single pad conditioning disk to increase functionality and effective pad surface engineering. For example, a certain type of sharp diamond can be used for the purpose of producing a desired surface texture, and a certain type of soft diamond (mild diamond) can be used for the purpose of maintaining the surface texture once it is created. The switching between the diamond types of the individual pad conditioning disks is achieved by the relative movement between the areas of the pad conditioning disk. Therefore, the pad dressing disc according to embodiments of the present invention has multiple diamond regions within the same pad dressing disc to provide dynamic control of the polishing pad surface engineering to achieve improved CMP process performance (eg, due to improved pitting/corrosion And fewer defects), and extend the life of the pad trimming disc and other components of the CMP tool.

Referring now to the drawings, FIGS. 1A and 1B respectively show a top schematic view and a cross-sectional view of a CMP system 10 according to an embodiment of the present invention. The CMP system 10 is used for the CMP process. The CMP system 10 includes a polishing fluid delivery arm 11 that is configured to deliver polishing fluid 12 during polishing. The polishing liquid 12 may include an abrasive-containing polishing slurry, or may include an abrasive-free liquid, which may be reactive. The polishing pad 13 is arranged on the platen 14 and is configured to polish a substrate (for example, a silicon wafer). The platen 14 is used to rotate the polishing pad 13 during processing, so that the polishing pad 13 flattens or polishes the surface of the substrate placed on the polishing pad 13. The polishing pad 13 is a consumable having a polished surface, and can 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 also includes a dresser element including a pad dressing disc 100 operatively connected to a pad dresser arm 17 via a shaft 16; the pad dresser arm 17 is connected to a machine base of a chemical mechanical polishing tool. The shaft 16 is arranged through the machine base of the CMP tool 10. The pad adjuster arm 16 can rotate about an axis perpendicular to the machine base. In the exemplary embodiment, rotation is facilitated by bearings between the machine base 130 and the pad dresser arm, so that the pad dresser arm 16 rotates the pad dressing disc 100. The disk 100 can be further rotated at a certain rotation speed. A downward force is applied to press the pad dressing disc 100 against the polishing pad 13.

The pad dressing disc 100 includes a plurality of regions including cutting elements that are selectively engaged with the polishing pad 13 based on the positioning of the plurality of regions. The regions can be activated independently and/or individually with respect to each other to selectively engage the polishing pad 13. For example, the diamond on the pad conditioning disk 100 is grouped into two or more regions. FIG. 2 shows a schematic diagram of a pad conditioning disk 100 having multiple regions that selectively engage polishing pads 13 in a first position according to an embodiment of the present invention. In the embodiment shown, the pad dressing disc 100 comprises a first area 1 with cutting elements 3 and a separate second area 2 with cutting elements 4. Here, the cutting elements 3 and 4 of the first region 1 and the second region 2 are the same. The cutting elements 3, 4 are intended to cut through the polishing pad 13 to restore and/or maintain the desired/optimal surface porosity of the polishing pad 13, as described above. The cutting elements 3 and 4 are diamonds in most cases, but may also be other cutting elements, such as SiC, SiO ₂ , ceramic materials, diamond-like films, and the like. In addition, the cutting element may also include or be replaced by a brush or other contact mechanism that may be used to help clean and maintain the pad surface. In the first position shown in FIG. 2, the cutting element 3 associated with the first area 1 is engaged with the polishing pad 13, while the cutting element 4 associated with the second area 2 is not engaged with the polishing pad 13. Therefore, the cutting element 4 remains because the cutting element 4 does not mechanically engage the surface of the polishing pad 13.

FIG. 3 shows a schematic diagram of a pad conditioning disk 100 having multiple regions that selectively engage polishing pads 13 in a second position according to an embodiment of the present invention. In the second position shown in FIG. 3, the positions of the first area 1 and the second area 2 have changed, the cutting element 4 associated with the second area 2 is now engaged with the polishing pad 13, and the associated with the first area 3 The cutting element 3 is now not engaged with the polishing pad 13. Therefore, the cutting element 3 is retained at least temporarily because the cutting element 3 is now not mechanically engaged with the surface of the polishing pad 13. FIG. 3 also shows a situation where the cutting edge of the cutting element 3 no longer effectively maintains the desired cutting performance, so the second area 2 is activated to actively engage the cutting element 4 with the polishing pad 13 while the first area 1 Move away from the polishing pad 13 so that the cutting element 3 is no longer engaged with the polishing pad 13.

Therefore, an exemplary embodiment of the pad conditioning disk 100 includes a plurality of regions 1, 2 each of which includes cutting elements that selectively engage the polishing pad 13 based on the positioning of the plurality of regions 1, 2 3. 4. When the first area 1 is placed closer to the polishing pad 13 than the second area 2, the cutting element 3 engages the polishing pad 13, as shown in FIG. When the second area 2 is placed closer to the polishing pad 13 than the first area 1, the cutting element 4 engages the polishing pad 13. Because each zone 1, 2 can move independently with respect to each other, the position change between zones 1, 2 can be achieved.

Each zone can be activated in various ways to facilitate movement of the zone. In an exemplary embodiment, these regions are activated by pushing one or more regions down along the Z axis while pulling up on other regions. If necessary, lift one or more deactivated areas from the polishing pad to avoid engaging the polishing pad when other areas are actively dressing the polishing pad. In addition, different downward forces can be applied to different areas if necessary. Various organizations can be used to activate various regions. The starting mechanism can be electric, mechanical or electromechanical. For example, via motors, batteries, shape memory actuators such as nitinol, solenoids, magnets, one or more servo motors, one or more stepper motors, electroactive polymers, piezoelectric bodies and switches, etc. The area is electrically actuated. This area can be mechanically actuated via springs, pneumatic elements, screws, hydraulic elements, pulleys, gears, lights, balls, pawls, etc. A combination of electrical and mechanical mechanisms can also be used. In addition, the pad conditioning disk with multiple areas can be a separate unit with its own activation/deactivation mechanism or controller, or alternatively, the pad conditioning disk can be connected to the CMP system 10, activated/deactivated by CMP The system 10 delivers.

Referring again to FIGS. 2-3, the connecting device 5 operably connects the plurality of areas 1, 2 and promotes movement between the plurality of areas 1, 2. The connecting device 5 is a knob, axle, hinge, pivot joint, lever, wheel, shaft, cylinder, or similar rotating device that allows activation of certain areas and deactivation of other areas. At a given time, the connecting device 5 rotates in a first direction, which activates certain areas, while other areas wait in line. For example, when the connecting device 5 rotates in the first direction, the first area 1 is activated (eg, lowered), engaging the cutting element 3 with the polishing pad 13 to cut into the pad for active dressing, and deactivated (eg , Lift) the second area 2 to remove the cutting element 4 from the polishing pad 13. Conversely, when the connecting device 5 rotates in a second direction opposite to the first direction, the second area 2 is activated (eg, lowered), engaging the cutting element 4 with the polishing pad 13 to cut into the pad for active Dressing while deactivating (eg, lifting) the first area 1 to remove the cutting element 3 from the polishing pad 13.

According to further embodiments, the pad conditioning disk 100 optionally includes multiple regions with different types of cutting elements to increase functionality. FIG. 4 shows a schematic view of a pad dressing disc 100 having multiple regions with different types of cutting elements 3', 4'according to an embodiment of the present invention. In the illustrated embodiment, the pad conditioning disk 100 includes a first area 1 with cutting elements 3'and a separate second area 2 with cutting elements 4'. Here, the cutting elements 3', 4'of the first area 1 and the second area 2 are different. The cutting element 3'may have a different size than the cutting element 4'and/or may have a different orientation and/or cutting angle than the cutting element 4'. For example, the cutting element 3'mounted on the first area 1 is block diamond, and the cutting element 4'mounted on the second area 2 is sharp diamond. In the first position shown in FIG. 4, the sharp diamond is bonded to the polishing pad 13 while the bulk diamond is not bonded to the polishing pad 13. Therefore, during specific applications, bulk diamonds are retained or intentionally not used.

FIG. 5 shows a schematic view of a pad dressing disc having multiple regions with different types of cutting elements in different positions compared to FIG. 4 according to an embodiment of the present invention. In the second position shown in FIG. 5, the positions of the first area 1 and the second area 2 have changed, the bulk diamond is now bonded to the polishing pad 13, and the sharp diamond is now not bonded to the polishing pad 13. Therefore, as the requirements of the CMP process have changed, sharp diamonds are retained or intentionally not used during certain applications.

The pad dressing disc 100 with multiple regions and multiple different types of cutting elements gives a certain desired effect. This mixed use of different types of cutting elements on the same pad dressing disc 100 provides the possibility to combine the advantages of different types of cutting elements, which could not have been achieved originally. For example, sharp diamonds can be installed in one area for aggressive area activation, and bulk diamonds can be installed in another area for mild area activation. In the ex-situ dressing process, during the period when the wafer is not on the polishing pad, the aggressive area is activated to form a deeper cut with sharp diamond teeth and effectively restore the polishing pad; then, the large Polishing pad fragments will flush out of the polishing pad surface without touching the wafer. During in-situ trimming, when polishing the wafers at the same time, the gentle zone is activated to utilize the bulk diamond teeth to provide a gentle cutting effect, which helps maintain a flat and consistent surface. Gentle zone activation also helps to achieve better pitting/corrosion performance while avoiding the possibility of scratching the wafer due to large polishing pad fragments.

Various combinations of cutting element types can be used in various areas. For example, the first area may use conventional diamond grit, while the second area may use chemical vapor deposition (CVD) diamond. More than two different types of cutting elements can be used in a single pad dressing disc. In a pad dressing disc with four different areas, four different types of cutting elements can be used. Alternatively, if the pad dressing disc has four regions, two different types of cutting elements can be used; two regions can have the same type of cutting elements, and the remaining two regions can have the same type of cutting elements.

Turning now to an exemplary embodiment of using a pad dressing disc according to an embodiment of the present invention. FIG. 6 shows a perspective view of a first position of a pad conditioning disk 200 having concentric regions according to an embodiment of the present invention. FIG. 7 shows a bottom view of the pad conditioning disk 200 of FIG. 6 according to an embodiment of the present invention. FIG. 8 shows a side view of the pad conditioning disk 200 of FIG. 6 according to an embodiment of the present invention. FIG. 9 shows a cross-sectional view taken along line A-A in FIG. 7 according to an embodiment of the present invention. As shown in FIGS. 6-9, the pad trimming disc 200 includes an outer area 201 and an inner area 202. The inner region 202 is at least slightly recessed relative to the outer region 201; the inner region 202 is located in 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 area 201 engage the polishing pad, while the cutting elements of the inner area 202 do not engage the polishing pad.

FIG. 10 shows a perspective view of the second position of the pad conditioning disk 200 of FIG. 6 according to an embodiment of the present invention. FIG. 11 shows a bottom view of the pad conditioning disk 200 of FIG. 10 according to an embodiment of the present invention. FIG. 12 shows a side view of the pad conditioning disk 200 of FIG. 10 according to an embodiment of the present invention. FIG. 13 shows a cross-sectional view taken along line A-A in FIG. 11 according to an embodiment of the present invention. As shown in FIGS. 10-13, the inner region 202 is now closer to the polishing pad, so 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 connecting device 205 facilitates the movement of the outer area 201 relative to the inner area 202 and vice versa. The connecting device 205 is a screw connection between the outer area 201 and the inner area 202. In an exemplary embodiment, the outer region 201 includes female threads arranged circumferentially along the inner surface of the outer region 201, and the inner region 202 includes corresponding male threads that mate with the female threads of the outer region 201. In another embodiment, the outer region 201 may include male threads, and the inner region 202 may include female threads. One or both of the areas 201, 202 in the clockwise or counterclockwise direction realize the relative movement of the areas 201, 202. Therefore, if the inner region 202 is activated (for example, a cutting element of the inner region 202 is 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 moved forward and backward The combination. 9 and 13 preferably show the relative movement between the outer region 201 and the inner region 202 due to the connecting device 205. In an alternative embodiment, the connection device 205 consists of a single helical groove as a thread in a position similar to the thread in the outer region 201 or the inner region 202 and a lip that fits within the groove and travels circumferentially around the groove/ The tongue/projection is formed to achieve relative vertical movement between the outer region 201 and the inner region 202.

Continuing with the pad conditioning disc 200, FIGS. 14-16 show an exemplary embodiment of activating one of the plurality of areas 201, 202 to change the position of the area 201 relative to the area 202. FIG. 14 shows a schematic view of the pad dressing disc 200 operably connected to the pad dresser arm 16 in the first position according to an embodiment of the present invention. The cutting elements of the outer area 201 are connected to the bottom layer 210 by fasteners 207. The bottom layer 210 is connected to the pad dresser arm 16 through a movable connection 19, as shown in FIG. The movable link 19 is a shaft fixedly connected to the bottom layer and/or outer area 201 and movably connected to the pad dresser arm 16. As shown in FIG. 15, the position of the connector 19a is for illustration only, and can be placed in a different position, for example, in the center of the disc, and other mechanical configurations can be used to complete the connection. In the first position shown in FIG. 14, the inner region 202 is recessed between the rings of the outer region 201 so 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 dressing disc 200 operably connected to a pad dresser arm 16 in a second position according to an embodiment of the present invention. In the second position shown in FIG. 16, the relative position between the outer area 201 and the inner area 202 has changed; the inner area 202 protrudes from the outer area 201. In this position, the cutting elements in the inner region 202 will now engage the polishing pad, while the cutting elements in the outer region 201 will no longer engage the polishing pad. The movement of the areas 201, 202 relative to each other is achieved by the threaded connection therebetween, as described above with respect to the connecting device 205. The motor rotates the movable link 19, which in turn rotates the bottom layer 110, and thus the outer area 201 fastened to the bottom layer 210. The rotation of the outer area 201 causes the inner area 202 to move up and down according to the rotation direction of the screw connection.

FIGS. 17-19 show another exemplary embodiment of activating one of the plurality of areas 201, 202 to change the position of the area 201 relative to the area 202. FIG. 17 shows a schematic view of the pad dressing disc 200 in the first position operatively connected to the pad dresser arm 16 according to an embodiment of the present invention. The cutting elements of the outer area 201 are connected to the base layer 210 by fasteners 207, while the cutting elements of the inner area 202 are connected to the separate base layer 211 by fasteners 208. The bottom layers 210, 211 are connected to the pad dresser arm 16 through separate connectors 19a and 19b, respectively. The movable links 19a, 19b are fixedly connected to the respective bottom layers and movably connected to the shaft of the pad conditioner arm 16, as shown in FIG. As shown in FIG. 18, the positions of the connecting pieces 19a, 19b are for illustration only, and can be placed in different positions, and other mechanical configurations can be used to complete the connection. In the first position shown in FIG. 17, the inner region 202 is recessed between the rings of the outer region 201 so 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 dressing disc 200 operably connected to a pad dresser arm 16 in a second position according to an embodiment of the present invention. In the second position shown in FIG. 19, the relative position between the outer area 201 and the inner area 202 has changed; the inner area 202 protrudes from the outer area 201. In this position, the cutting elements in the inner region 202 will now engage the polishing pad, while the cutting elements in the outer region 201 will no longer engage the polishing pad. The movement of the regions 201, 202 relative to each other is achieved by actuating one or both of the movable links 19a, 19b along the Z axis. Actuators, such as motors, pneumatic actuators, hydraulic actuators, mechanical actuators, etc., actuate one or both of the movable links 19a, 19b along the Z axis to change the position of the regions 201, 202 . For example, the movable connector 19a is actuated in the upward direction to raise the outer region 201 by a certain distance, and the movable connector 19b is actuated in the downward direction to lower the inner region 202. In other examples, only the movable link 19a or only the movable link 19b is actuated to actuate the regions 201, 202 to a desired position or configuration.

The various regions of the pad conditioning disk according to embodiments of the invention can be designed into various geometries and configurations. For example, these regions may be concentric rings, radial pies, spiral ribs, and dies, which include round pad dressing discs. Figures 20-23 show only a few possible configurations for multiple areas. FIG. 20 shows a pad conditioning disk 300 according to an embodiment of the present invention. The pad conditioning tray 300 includes two separate areas 301, 302, which are arranged concentrically into an outer area 301 and an inner area 302. FIG. 21 shows a pad conditioning disk 400 according to an embodiment of the present invention. The pad conditioning disk 400 includes three areas 401, 402, and 403. The regions 401 and 403 are arranged in a radial pie-shaped cross section along the outer ring of the pad dressing disk 400. The area 402 is arranged as a central part within the outer ring of the pad conditioning disk 400. FIG. 22 shows a pad conditioning disk 500 according to an embodiment of the present invention. The pad dressing tray 500 includes a total of sixteen areas arranged circumferentially around the pad dressing tray 500. This total of sixteen areas consists of four different types of cutting elements labeled 501, 502, 503 and 504. Although a total of sixteen areas are shown, any number of areas can be used in a similar configuration. FIG. 23 shows a pad conditioning disk 600 according to an embodiment of the present invention. The pad dressing tray 600 includes a total of thirty-two areas arranged in rows and columns on the pad dressing tray 600. The thirty-two areas are composed of five different types of cutting elements labeled 601, 602, 603, 604, and 605. Although a total of thirty-two areas are shown, any number of areas can be used in a similar configuration. In addition, O-rings and/or other insulating devices are optionally provided between the areas to avoid the accumulation of chemicals/slurry/by-products.

Continuing to refer to the drawings, FIG. 24 shows a CMP tool 1000 using a pad to trim a disc according to an embodiment of the present invention. The CMP tool 1000 includes a polishing machine having a machine base 130, a polishing liquid delivery arm 190, a polishing pad 104 disposed on a platen 102, a polishing head 106, a dresser assembly 122, and a controller 152. The machine base 130 supports the platen 102, the polishing liquid delivery arm 190, and the finisher assembly 122. The platen 102 supports the polishing head 106. The polishing head 106 can be rotated by the motor 120, so that the substrate 118 rotates around the 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 used to rotate the polishing pad 104 during processing so that the polishing pad 104 planarizes the surface of the substrate 118 placed on the pad 104 ("polishing"). The polishing pad 104 is a consumable having a polished surface, and can be fixed to the platen 102. The motor 112 coupled to the platen 102 through the shaft 114 rotates the platen 102 and the polishing pad 104. The polishing pad 104 is moved relative to the substrate 118 held in the polishing head 106 by the motor 112. In the illustrated embodiment, the motor 112 rotates the platen 102 in the X-Z plane about a central axis A perpendicular to the platen 102. Sensor 150 may be utilized to obtain the amount of force required to rotate platen 102 and polishing pad 104 relative to substrate 118 and/or dresser assembly 122.

The polishing liquid delivery arm 190 supplies the polishing liquid 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 the arm 128 support the dressing head 108 above the platen 102. The dressing head 108 retains a dressing disc according to an embodiment of the present invention, which is selectively placed in engagement with the polishing pad 104 to dress the surface of the polishing pad 104. The shaft 126 is set through the machine base 130 of the CMP tool 1000. The shaft 126 can rotate about the axis B perpendicular to the machine base 130, and the bearing 132 between the machine base 130 and the shaft 126 facilitates the rotation, causing the arm 128 to rotate the dressing head 108. In one embodiment, a sweep actuator 144 coupled to the shaft 126 can rotate the shaft 126 to push the arm 128 to scan the dressing head 108 over the polishing pad 104. The dressing head 108 rotates the dressing coil about an axis C that is generally arranged to pass through the dressing disc. In one embodiment, a motor 134 is used to rotate the dressing disk relative to the polishing pad 104. In one embodiment, the motor 134 is arranged in the housing 136 at the distal end of the arm 128.

A downward force actuator 140 is used to push the dressing disc toward the polishing pad 104. The downward force actuator 140 is configured to selectively set the force exerted on the polishing pad 104 by the dressing disc 124. In one embodiment, the downward force actuator 140 may be disposed between the arm 128 and the shaft 126, or in other suitable locations. The downward force sensor 142 is used to detect the amount of downward pressure indicating the dressing disc applied to the polishing pad 104. In one embodiment, the downward force sensor 142 may be arranged coaxially with the downforce actuator 140, or may be placed in other suitable locations.

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

The controller 152 is generally designed to facilitate the control and automation of the CMP tool 1000, and typically includes a central processing unit (CPU) 154, memory 156, and supporting circuits (or I/O) 158. The CPU 154 can be one of any form of computer processor used in industrial settings for controlling various system functions, substrate movement, chamber processing, processing timing, and supporting hardware (eg, sensors, robots, motors) , Timing equipment, etc.) and monitoring processes (eg, chemical concentration, processing variables, chamber processing time, I/O signals, etc.). The memory 156 is connected to the CPU 154, and may be one or more easily available memories such as random access memory (RAM), read only memory (ROM), floppy disk, hard disk, or local or remote Any other form of digital memory. Software instructions and data can be encoded and stored in memory to instruct the CPU 154. The support circuit 158 is also connected to the CPU 154 for supporting the processor in a conventional manner. Supporting circuits 158 may include cache memory, power supplies, clock circuits, input/output circuits, subsystems, and so on. The controller 152 can read programs or computer instructions to determine which tasks can be performed on the substrate. Preferably, the program is software readable by the controller 152, which includes code for performing tasks related to monitoring, performing, and controlling the movement, support, and/or positioning of the substrate in the polishing machine 100. In one embodiment, the controller 152 is used to control the robotic device to control the strategic movement, timing, and operation of the polisher 100 to make the process repeatable, resolve queue timing issues, and prevent over- or under-treatment of the substrate .

In addition, the pad dressing disc according to an embodiment of the present invention is used to dress the polishing pad of the CMP tool. For example, a method for dressing a polishing pad of a chemical mechanical polishing tool includes selectively activating selected areas of a pad conditioning disk having multiple areas. Each of the plurality of regions has cutting elements for dressing the polishing pad. The choice of the area used to trim the polishing pad depends on several factors. The multiple factors include the polishing recipe, the polishing project, the usage time of the chemical mechanical polishing tool, the interval of the multiple wafers polished by the chemical mechanical polishing tool, the excellent surface porosity of the polishing pad, and the like.

For example, the initial area is selected for dressing the polishing pad and activated accordingly, so that the cutting elements of the initial area will be used for dressing the polishing pad. The initial region is selected based on the fact that the CMP process is currently being performed ex-situ, when the wafer is not simultaneously polished on the polishing pad, and the cutting elements in the initial region are suitable for ex-situ dressing. A downward force (eg, downforce) is applied to the pad conditioning disk to engage the cutting elements in the initially selected area with the polishing pad, but the cutting elements in other areas do not engage the polishing pad. If the CMP process is changed to in-situ trimming, when the wafer is polished on the polishing pad at the same time, a new different area is selectively activated based on the change from ex-situ trimming to in-situ trimming. The combination of ex-situ and in-situ produces an ideal pad surface texture, greatly reducing pad trim by-products, and avoiding excessive pad wear.

As another example, the initial region is selected for dressing the polishing pad and activated accordingly, so that the cutting elements of the initial region will be used for dressing the polishing pad. The initial area is selected to trim the polishing pad to accommodate the number of "x" wafers polished by the CMP tool. A downward force (eg, downforce) is applied to the pad conditioning disk to engage the cutting elements of the initially selected area with the polishing pad, but the cutting elements of other areas do not engage the polishing pad, thereby retaining these cutting elements. After polishing "x" wafers by the CMP tool, a new different area is selectively activated to trim the polishing pad for additional "x" wafers. In this case, both areas have the same type of cutting element. In this way, the cutting elements wear at different rates, and there is no need to change the pad dressing disc to take advantage of the new cutting elements to obtain good performance.

In another example, during the run-in period of the polishing pad where the polishing pad is new, used, or not actively used for a period of time, an area of the cutting element is activated by some type of diamond that engages the surface of the polishing pad to produce The desired surface texture/porosity, other areas are disengaged. During the process of actively using the polishing pad for wafer polishing, different areas are activated with a different type of diamond, and the first area of the diamond is disengaged to produce different types of pad surface texture/porosity (eg, Smooth and consistent), and cutting by-products of different sizes (for example, thinner). During polishing, especially during ex-situ trimming, when the wafer is not polished on the pad at the same time, a certain area of diamond is engaged with the pad surface by some type of diamond to produce the desired surface texture/porosity, Cutting byproducts of a certain size, while other areas are disengaged. During the polishing process, especially during in-situ trimming, when polishing the wafer on the pad at the same time, a different type of diamond is used to activate different areas, and the first area of the diamond is disengaged to produce different types of pads Surface texture/porosity (for example, smooth and consistent), and cutting by-products with different sizes (for example, finer). The combination produces ideal performance and avoids excessive wear.

In addition, the method can also be applied during the CMP process, where during the first part of the polishing process, the first area of diamond is activated by some type of diamond engaging the pad surface to produce the desired surface texture/porosity , While the other areas are disengaged. During the second part of the polishing, a different type of diamond is used to activate the second area of diamond, while the first area of diamond is disengaged to produce different types of pad surface texture/porosity.

In addition, different applications can share the same board. For example, if the first application is being used, the first area of diamond is activated by some type of diamond engaging the pad surface to produce the desired surface texture/porosity, while the other areas are disengaged. If a second application is being used, the second area of diamond is activated by some type of diamond bonding with the pad surface to produce the desired surface texture/porosity, while the other areas are disengaged. If a third application is being used, the third area of diamond is activated by some type of diamond bonding with the pad surface to produce the desired surface texture/porosity, while the other areas are disengaged, and so on.

Although the present disclosure has been described in conjunction with the specific embodiments outlined above, it is clear that many alternatives, modifications, and variations will be apparent to those skilled in the art. Therefore, the preferred embodiments of the present disclosure as described above are intended to be illustrative, not limiting. As required by the scope of the attached patent application, various changes can be made without departing from the spirit and scope of the present invention. The scope of patent application provides the coverage of the present invention and should not be limited to the specific examples provided herein.

1: the first area 2: the second area 3,3’: Cutting elements 4,4’: Cutting elements 5: Connect the device 10: CMP system 11: conveyor arm 12: polishing liquid 13: polishing pad 14: Platen 15: Polishing head 16: axis 17: pad trimmer arm 19: movable connector 19a: connector 19b: connector 100: pad trimming disc 102: platen 104: polishing pad 106: polishing head 108: Dressing head 112: Motor 114: axis 118: substrate 120: motor 122: Dresser assembly 124: Finishing disk 126: Shaft 128: arm 130: Machine base 132: Bearing 134: Motor 136: Shell 140: downward force actuator 142: downward force sensor 144: Scan actuator 148: Sensor 150: Sensor 152: Controller 154: Central Processing Unit 156: Memory 158: Support circuit 190: conveyor arm 200: pad trimming disc 201: Outer area 202: inner area 205: Connect the device 207: Fastener 208: Fastener 210: bottom layer 211: Ground floor 300: pad trimming disc 301: Outer area 302: Inner area 400: pad trimming disc 401: Area 402: Area 403: Area 500: pad trimming disc 501: Cutting element 502: Cutting element 503: Cutting element 504: Cutting element 600: pad trimming disc 601: Cutting element 602: Cutting element 603: Cutting element 604: Cutting element 605: Cutting element 1000: CMP tool A: Central axis B: axis C: axis D: Central axis

Some embodiments will be described in detail with reference to the following drawings, in which the same reference numerals denote the same components, where: FIG. 1A shows a schematic top view of a CMP system according to an embodiment of the present invention; FIG. 1B shows a cross-sectional view of the CMP system in FIG. 1A according to an embodiment of the present invention; 2 shows a schematic diagram of a pad conditioning disk having multiple regions that selectively engage polishing pads in a first position according to an embodiment of the invention; FIG. 3 shows a schematic diagram of a pad conditioning disk having multiple regions that selectively engage polishing pads in a second position according to an embodiment of the present invention; 4 shows a schematic view of a pad dressing disc having multiple regions with different types of cutting elements according to an embodiment of the present invention; FIG. 5 shows a schematic view of a pad dressing disc having multiple regions with different types of cutting elements whose position changes compared to FIG. 4 according to an embodiment of the present invention; 6 shows a perspective view of a first position of a pad conditioning disk with concentric areas according to an embodiment of the invention; 7 shows a bottom view of the pad conditioning disk of FIG. 6 according to an embodiment of the present invention; 8 shows a side view of the pad conditioning disk of FIG. 6 according to an embodiment of the present invention; 9 shows a cross-sectional view taken along line A-A in FIG. 7 according to an embodiment of the present invention; 10 shows a perspective view of the second position of the pad conditioning disk of FIG. 6 according to an embodiment of the present invention; 11 shows a bottom view of the pad dressing tray of FIG. 10 according to an embodiment of the present invention; 12 shows a side view of the pad dressing disc of FIG. 10 according to an embodiment of the present invention; 13 shows a cross-sectional view taken along line A-A in FIG. 11 according to an embodiment of the present invention; 14 shows a schematic view of a pad dressing disc operably connected to a pad dresser arm in a first position according to an embodiment of the invention; 15 shows a top view of FIG. 14 according to an embodiment of the present invention; FIG. 16 shows a schematic view of a pad dressing disc operably connected to a pad dresser arm in a second position according to an embodiment of the present invention; FIG. 17 shows a schematic view of a pad dressing disc operably connected to a pad dresser arm in a first position according to an embodiment of the present invention; 18 shows a top view of FIG. 17 according to an embodiment of the present invention; FIG. 19 shows a schematic view of a pad dressing disc operably connected to a pad dresser arm in a second position according to an embodiment of the invention; FIG. 20 shows a first configuration of a pad conditioning disk according to an embodiment of the present invention; 21 shows a second configuration of the pad conditioning disk according to an embodiment of the present invention; 22 shows a third configuration of the pad conditioning disk according to an embodiment of the present invention; FIG. 23 shows a fourth configuration of the pad conditioning disk according to an embodiment of the present invention; FIG. 24 shows a CMP tool using a pad to trim a disc according to an embodiment of the present invention.

no

1: the first area

2: the second area

3: Cutting elements

4: Cutting element

5: Connect the device

13: polishing pad

100: pad trimming disc

Claims (10)

A pad dressing disc configured to dress a polishing pad of a chemical mechanical polishing tool. The pad dressing disc includes: A plurality of regions including cutting elements selectively engaged with the polishing pad based on the positioning of the plurality of regions. The pad conditioning disk of claim 1, wherein the plurality of regions can move relative to each other so that the cutting element of the first region of the plurality of regions engages the polishing pad during chemical mechanical polishing While the cutting element of the second area of the plurality of areas is not engaged with the polishing pad. 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. The pad conditioning disk of claim 1, wherein the first region of the plurality of regions includes granular diamond having a certain shape, size, distribution, and density, and the second region of the plurality of regions includes coated A chemical vapor deposition (CVD) diamond film on a textured surface. A chemical mechanical polishing tool, including: A polishing pad placed on the platen, the polishing pad being configured to polish the substrate; A polishing fluid delivery arm configured to deliver polishing fluid during pad dressing; and A dresser element. The dresser assembly includes: A pad conditioner arm connected to the machine base of the chemical mechanical polishing tool, and A pad dressing disc connected to the pad dresser arm, the pad dressing disc having at least two regions, which are activated relative to each other for selective engagement with the polishing pad. The chemical mechanical polishing tool according to claim 5, wherein the chemical mechanical polishing tool includes elements and mechanisms for activating and deactivating zone switching. A method for trimming a polishing pad during a chemical mechanical polishing process, the method includes: Selectively activate a selected area in a pad dressing disc having a plurality of areas with cutting elements for dressing the polishing pad, wherein the selection of the area for dressing the polishing pad depends on multiple One of the factors; and Downforce is applied to the pad conditioning disk to engage the cutting elements in the selected area with the polishing pad, but the cutting elements in other areas do not engage the polishing pad. The method according to claim 7, wherein the plurality of factors include a polishing recipe, a polishing project, a usage time of a chemical mechanical polishing tool, an interval of a plurality of wafers polished by the chemical mechanical polishing tool, a defined plan table or Feedback from the dynamic feedback system, further wherein the factor is the feedback from the dynamic feedback system, the feedback includes wafer performance, friction between the wafer and the polishing pad, roughness measurement of the polishing pad, and/or polishing pad Measurement of porosity. The method according to claim 7, wherein the method further comprises: Selectively activating different regions of the pad conditioning disk based on a change in one or more of the plurality of factors, wherein the selectively activating different regions includes actuating the movable connection of the pad conditioning arm to oppose The position of the selected area is adjusted in the different areas. The method of claim 7, wherein: The factor for selecting the area for trimming the polishing pad is the type of trimming, the type of trimming is the in-situ trimming period or the ex-situ trimming period, further, wherein during the ex-situ trimming, the selected area The cutting element is engaged with the polishing pad, and the cutting element in another area is disengaged from the polishing pad, and during the in-situ dressing, the cutting element in the selected area is disengaged from the polishing pad, and the other A region of cutting elements is engaged with the polishing pad; or The factor for selecting the area for trimming the polishing pad is whether the chemical mechanical polishing process is in the run-in phase or wafer processing phase, further, wherein in the run-in phase, the cutting elements of the selected area and the polishing pad Engage, and the cutting element in another area is disengaged from the polishing pad, and in the wafer processing stage, the cutting element in the selected area disengages from the polishing pad, and the cutting element in the other area disengages from the polishing pad The polishing pad is engaged.

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