CN221517421U - Chemical mechanical polishing equipment - Google Patents

Abstract

The present application provides a chemical mechanical polishing apparatus, comprising: the polishing device comprises a polishing platform, a polishing pad assembled on the polishing platform, a plurality of polishing pad trimmers and a controller, wherein the polishing pad trimmers are respectively used for trimming and/or cleaning the working surface of the polishing pad in working; the controller is electrically connected with the plurality of polishing pad trimmers respectively and controls the plurality of polishing pad trimmers to work. The dynamic selection characteristics of the plurality of polishing pad trimmers of the polishing equipment can better prolong the service life of consumable materials, save the cost of the consumable materials and the maintenance time of the equipment, and can also meet the high requirements on flatness and accuracy in advanced technology.

Description

Chemical mechanical polishing equipment

Technical Field

The application relates to the technical field of semiconductor manufacturing equipment, in particular to chemical mechanical polishing equipment.

Background

CMP is a chemical mechanical polishing process, which is a means for global planarization in integrated circuit fabrication, and belongs to a technology combining chemical action and mechanical action.

Referring to fig. 1, a typical polishing apparatus 100 for wafer polishing includes a polishing platen 101, a polishing pad 102, a polishing head 103, and a polishing pad conditioner 104. The polishing platen 101 is a supporting platen of the entire polishing apparatus 100, the polishing pad 102 is disposed on the polishing platen 101, and the polishing head 103 carries a wafer (not shown) and applies a certain pressure to drive the wafer to move relative to the polishing pad 102 to polish the wafer, so as to planarize the wafer. The polishing pad conditioner 104 includes a conditioning disk, the working surface of which is in engagement with the polishing surface of the polishing pad 102 and moves relatively during operation, maintaining the roughness of the surface of the polishing pad 102. Meanwhile, in order to satisfy various chip manufacturing processes, the polishing apparatus 100 is further provided with a polishing liquid supply device 105 for supplying various polishing liquids to the polishing pad 102 to obtain efficient polishing rate and effect.

With the increase of the service life of the polishing pad 102, the surface of the polishing pad 102 is subjected to severe abrasion, and the chips, residues of polishing particles and byproducts on the surface of the polishing pad 102 block the grooves and holes on the surface of the polishing pad 102, so that the surface of the polishing pad 102 is glazed, the surface roughness of the polishing pad 102 is reduced, and the removal rate and uniformity of materials are affected, thereby further affecting the polishing quality of the chemical mechanical polishing process.

In order to extend the useful life of the polishing pad, a polishing pad conditioner is typically employed to restore the proper roughness to the polishing pad. However, with the continued development of the process, single pad conditioner has not been able to meet the requirements for flatness and cleanliness in polishing process. In addition, the limitation of the short service life of the dressing disc of the polishing pad dresser also has an influence on the production cost of enterprises and the effective working time of equipment.

Therefore, there is a need to provide a new chemical mechanical polishing apparatus for solving the problems of better prolonging the service life of consumable materials, reducing the cost of consumable materials and reducing the maintenance time of the apparatus.

Disclosure of utility model

An embodiment of the present application provides a chemical mechanical polishing apparatus, including: a grinding platform; a polishing pad mounted on the polishing platen; a plurality of polishing pad trimmers, each of which is used for trimming and/or cleaning the working surface of the polishing pad during operation; and the controller is respectively and electrically connected with the plurality of polishing pad trimmers and controls the plurality of polishing pad trimmers to work.

In some embodiments, the polishing pad conditioner comprises a functional head and a transmission arm, wherein the functional head is arranged at one end of the transmission arm, and when the polishing pad conditioner works, the functional head acts on the working surface of the polishing pad under the drive of the transmission arm to finish and/or clean the working surface of the polishing pad.

In some embodiments, the functional head is detachably connected to the actuator arm.

In some embodiments, the functional head includes a polishing pad conditioning head and/or a polishing pad cleaning head.

In some embodiments, the polishing pad conditioner head includes a conditioner head body and diamond abrasive particles disposed on the conditioner head body.

In some embodiments, the polishing pad cleaning head includes a cleaning head body and a cleaning brush disposed on the cleaning head body.

In some embodiments, the controller controls operation of a plurality of the polishing pad conditioner to act on different areas of the working surface of the polishing pad, respectively.

In some embodiments, the controller controls the swing path and/or swing speed of the functional head to cause a plurality of the pad conditioners to operate to respectively act on different areas of the working surface of the polishing pad.

In some embodiments, the plurality of polishing pad conditioners is 2 to 4.

In some embodiments, the polishing device further comprises a polishing head, wherein the polishing head is used for driving the surface to be polished of the wafer to be polished to move relative to the surface of the polishing pad; and a polishing liquid supply device for supplying a polishing liquid to the polishing pad and the working surface of the polishing head.

The chemical mechanical polishing equipment provided by the embodiment of the application comprises a plurality of polishing pad trimmers, and multiple selections can be provided for polishing consumable maintenance, so that the service life of the consumable is prolonged better, the consumable cost and the equipment maintenance time are saved, and the productivity is increased. Meanwhile, the dynamic selection function of the plurality of polishing pad trimmers can be better suitable for different process requirements, and can meet the high requirements on flatness and accuracy in advanced processes.

Drawings

The following drawings describe in detail exemplary embodiments disclosed in the present application. Wherein like reference numerals refer to like structure throughout the several views of the drawings. Those of ordinary skill in the art will understand that these embodiments are non-limiting, exemplary embodiments, and that the drawings are for illustration and description only and are not intended to limit the scope of the application, as other embodiments may equally well accomplish the inventive intent in this disclosure. It should be understood that the drawings are not to scale.

Wherein:

FIG. 1 is a schematic top view of a prior art single pad conditioner system;

FIG. 2 is a schematic top view of a chemical mechanical polishing apparatus according to the present application;

FIG. 3 is a schematic view of the footprint of a polishing pad conditioner functional head on a polishing pad surface;

FIG. 4 is a schematic top view of a polishing apparatus (same polishing pad conditioner) according to some embodiments of the application;

Fig. 5 is a schematic top view of a polishing apparatus (different polishing pad conditioner) according to some embodiments of the application.

Detailed Description

The following description provides specific applications and requirements of the application to enable any person skilled in the art to make and use the application. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the application. Thus, the present application is not limited to the embodiments shown, but is to be accorded the widest scope consistent with the claims.

In the chemical mechanical polishing process, the interaction between various polishing consumables is critical in ensuring the stability of the process, for example, the polishing pad and the conditioning disk, and the quality of the conditioning disk for conditioning the polishing pad is related to the stability of the wafer polishing rate. Replacement is required when the abrasive consumable reaches its useful life, or when its performance is found to be degraded.

In general, the life of various polishing consumables is different, and polishing head > polishing pad > conditioning disk. For example, the service life of the polishing head/polishing pad/dressing disk is 6000 sheets/3000 sheets/1500 sheets, and then every 1500 sheets need to be replaced, because the service life of the dressing disk is the shortest, and other related consumable parts which have not reached the service life need to be replaced together, which causes unnecessary waste. Moreover, the grinding consumables are frequently replaced, so that the process is disturbed to a certain extent, and the working time of the machine is shortened. If there are two pad conditioners (i.e., two conditioning discs), the added lifetime of the conditioning discs is 3000, which reduces the time for one replacement, increases the operating time of the apparatus, increases the throughput, and reduces waste.

In addition, as the wafer polishing process progresses, the main component of the polishing liquid is gradually changed into ceria to bring about a high polishing rate, but the high viscosity property of ceria also increases the risk of abrasive particles remaining on the wafer. Thus, it is desirable to simultaneously condition and clean the polishing pad during polishing.

Based on the above description, an embodiment of the present application provides a chemical mechanical polishing apparatus, referring to a schematic top view of the chemical mechanical polishing apparatus shown in fig. 2, including:

a polishing platen 1;

A polishing pad 2 mounted on the polishing platen 1;

A plurality of polishing pad trimmers 4, each of the plurality of polishing pad trimmers 4 being operative for trimming and/or cleaning a working surface of a polishing pad;

and a controller 7 electrically connected to the plurality of polishing pad trimmers 4, respectively, for controlling the operation of the plurality of polishing pad trimmers 4.

The polishing platform 1 is used for detachably fixing the polishing pad 2, and when the chemical mechanical polishing equipment works, the polishing platform 1 is driven to rotate so as to drive the polishing pad 2 to rotate together.

The polishing pad 2 rotates along with the polishing platform 1, and when the polishing pad contacts with a wafer, the surface convexity of the polishing pad 2 rubs with the wafer, so that the surface of the wafer is flattened.

The polishing pad conditioner 4 can automatically enter a corresponding working state after relevant working parameters are set. The above-described operation states include start or stop of the polishing pad conditioner 4, conditioning and/or cleaning of the working surface of the polishing pad 2 by the polishing pad conditioner 4, an area where the polishing pad conditioner 4 acts on the working surface of the polishing pad 2, and the like.

The controller 7 is electrically connected to the polishing pad trimmers 4, and is configured to set operating parameters for the polishing pad trimmers 4, so as to control the operating states of any one of the polishing pad trimmers 4 individually or simultaneously, thereby configuring a specific cooperative operating mode to meet the trimming requirement of the specific polishing pad 2.

Specifically, the controller 7 may control the plurality of polishing pad conditioners 4 to move to different areas of the upper surface of the polishing pad 2 during operation, contact the upper surface of the polishing pad 2, and take on a plurality of different tasks. For example, when dressing the polishing pad 2, different dressing strategies (different dressing durations or different dresser materials, etc.) may be applied to the polishing pad 2; in cleaning the polishing pad 2, different cleaning durations may be set for different areas of the polishing pad 2. For different chip manufacturing processes, one of the polishing pad trimmers can be arranged to work independently, and different groups of the polishing pad trimmers can be arranged to work simultaneously to finish trimming and/or cleaning the polishing pad cooperatively.

The technical scheme of the invention is described in detail below with reference to the examples and the accompanying drawings.

Referring to fig. 2, two pad conditioners 4 are illustrated. In some embodiments of the present application, the polishing pad conditioner 4 includes 2 or more, for example, 3, 4, 5, etc. The polishing apparatus of the present application does not limit the number of polishing pad conditioners 4, and the number of polishing pad conditioners 4 can be determined according to the space condition above the polishing pad 2 and the maintenance requirements of a specific process for the polishing pad. In principle, the positions and the number of the polishing pad trimmers 4 are set so that they can be uniformly distributed over the polishing pad 2 during operation and interference between adjacent polishing pad trimmers 4 is avoided.

In some embodiments, as shown in fig. 2, the pad conditioner 4 includes a functional head 400 and a drive arm 402. The functional head 400 is disposed at one end of the driving arm 402, and the other end of the driving arm 402 is connected to the power rotating shaft 404. The power shaft 404 is used as a rotation shaft perpendicular to the center line of the wafer direction, and the driving arm 402 drives the functional head 400 to reciprocate horizontally on the surface of the polishing pad 2 along the swinging path 6. The swing path of the functional head 400 determines the working area on the surface of the polishing pad 2 that the functional head 400 can cover. When the polishing pad conditioner 4 is operated, the functional head 400 acts on the working surface of the polishing pad 2 under the drive of the driving arm 402, and the working surface of the polishing pad 2 is conditioned and/or cleaned.

In some embodiments, the controller 7 controls the operation of the plurality of pad conditioners 4 to act on different areas of the working surface of the polishing pad 2, respectively.

Specifically, in some embodiments, the controller 7 controls the swing path 6 and/or the swing speed of the functional head 400 so that the plurality of polishing pad trimmers 4 respectively act on different areas of the working surface of the polishing pad 2 in different working states when in operation.

Referring to fig. 3, a schematic diagram of the coverage area of the functional head 400 of the pad conditioner 4 on the surface of the polishing pad 2 is shown. When the polishing pad 2 is in a rotating state, two ends of the swing path 6 of the functional head 400 correspond to virtual concentric circles a and B of the polishing pad 2, respectively, and then the annular region C between the concentric circles a and B is a working region that can be covered by the functional head 400. In view of the fact that the actuator arm 402 can be extended and retracted and the end point of the swing path 6 can be set as desired, the working area of the functional head 400 of each pad conditioner 4 can be adjusted as desired to any annular area of the entire surface of the polishing pad 2. Based on this feature, the dynamic and flexible configuration of the pad conditioner 4 can be tailored to the actual wafer polishing process requirements.

In some embodiments, the upper surface of the polishing pad 2 is divided into a plurality of annular regions, and different repair strengths are required. At this time, the controller 7 may be configured such that only one polishing pad conditioner 4 is operated (the remaining polishing pad conditioners 4 are not operated), and the swing path 6 of the functional head 400 is divided into a plurality of segments, which respectively correspond to a plurality of annular regions covering the upper surface of the polishing pad 2. Further, the controller 7 sets different swing speeds for the plurality of swing path segments, so that a specific repair strength for a specific annular region can be realized.

In some embodiments, the controller 7 may also configure a plurality of polishing pad conditioners 4 to work separately on a plurality of different annular areas of the upper surface of the polishing pad 2 to cooperatively cover the entire upper surface of the polishing pad 2. Specifically, in some embodiments, two pad conditioners 4 having identical performance parameters are provided. In such a configuration, there may be a variety of applications: 1) Each polishing pad conditioner 4 is responsible for a half area of the polishing pad 2, and in the case where the swing speed of the polishing pad conditioner 4 conditioning head 401 is unchanged, the speed of conditioning the polishing pad 2 can be doubled, and accordingly, the condition and performance index of the polishing pad 2 are improved, so that the polishing rate stability of the polishing apparatus is improved. 2) Maintaining the polishing rate stability, the speed of dressing the polishing pad 2 by each polishing pad conditioner 4 may be reduced by half, or the two polishing pad conditioners 4 may be operated alternately, thereby extending the life of the conditioner head 401 by 1 time, and reducing the downtime due to replacement of consumables. 3) For the precise control requirements of the dressing of the different polishing pad 2 areas, the speed of each polishing pad dresser 4 can be set to correspond to the different area requirements one by one.

In some embodiments, the polishing pad conditioner 4 on the upper surface of the polishing pad 2 is a polishing pad conditioner head 401. As shown in the schematic top view of the polishing apparatus of fig. 4, two polishing pad trimmers 41 are provided on the upper surface of the polishing pad 2. The polishing pad conditioner 41 includes a conditioning head 401 and a transmission arm 402. The two pad conditioners 41 may have the same or different performance parameters. The different performance parameters of the pad conditioner 41 may be represented by different conditioning speeds and different materials of the pad conditioner head 401. The combination of polishing pad trimmers 4 of different performance can realize the precise control of the trimming of the areas of different polishing pads 2.

In some embodiments, the plurality of polishing pad conditioners 4 on the upper surface of the polishing pad 2 include at least one polishing pad conditioner head 401 and one polishing pad cleaning head 403. As shown in the schematic top view of the polishing apparatus of fig. 5, the upper surface of the polishing pad 2 includes one polishing pad conditioner 41 and one polishing pad conditioner 42. Wherein the pad conditioner 41 includes a conditioner head 401 and a transmission arm 402, and the pad conditioner 42 includes a cleaning head 403 and a transmission arm 402. The combination of the polishing pad dressing head 401 and the polishing pad cleaning head 403 enables the dressing and cleaning of the polishing pad 2 to be performed simultaneously, and simultaneously ensures the requirements of the polishing rate and the cleaning effect, thereby providing a guarantee for the new development of the chip manufacturing process.

In some embodiments, the functional heads 400 are detachably connected with the transmission arms 402, so that the functional heads 400 with different characteristics can be conveniently changed, and the conversion time is saved. In some embodiments, the connection structure of the different types of functional heads 400 and the driving arm 402 may be the same, and only the functional heads 400 may be replaced to convert the polishing pad conditioner 4 from the conditioning function to the cleaning function, or to convert the polishing pad conditioner 4 from the cleaning function to the conditioning function, so as to meet different process requirements.

In some embodiments, referring to fig. 4 and 5, the functional heads of the polishing pad conditioner described above include a polishing pad conditioner head 401 and/or a polishing pad cleaning head 403. During polishing of a wafer, the roughness and cleanliness of the surface of the polishing pad 2 directly affect the quality of the polishing process. In order to extend the useful life of the polishing pad 2 and reduce the impact of abrasive particle residue on the wafer, the polishing pad 2 is conditioned and/or cleaned while the wafer is polished. The polishing pad dressing head 401 is used for recovering the roughness of the surface of the polishing pad 2; the polishing pad cleaning head 403 is used to remove debris, polishing particle residues, byproducts, and the like from the polishing pad 2.

In some embodiments, the polishing pad conditioner head 401 includes a conditioner head body and diamond abrasive grains disposed on the conditioner head body for restoring the roughness of the polishing pad 2. The diamond particles may restore the polyurethane flattened on the polishing pad 2 to an upright state so that the roughness of the polishing pad 2 increases to secure the polishing rate and the polishing quality.

In some embodiments, the polishing pad cleaning head 403 includes a cleaning head body and a cleaning brush disposed on the cleaning head body for cleaning the polishing pad 2. The cleaning brush can remove the chips or particles remained in the grooves and holes on the surface of the polishing pad 2. The polishing pad cleaning head 403 may further include a vacuum suction pipe to suck the cleaned waste while the cleaning brush brushes the polishing pad 2.

In some embodiments, the chemical mechanical polishing apparatus further includes a polishing head 3, where the polishing head 3 operates to drive the surface to be polished of the wafer to be polished to move relative to the surface of the polishing pad 2. The polishing head 3 applies a certain pressure to the wafer to polish the wafer so that the wafer is planarized. In some embodiments, the chemical mechanical polishing apparatus of the present application further includes a polishing liquid supply device 5 for supplying a polishing liquid to the working surfaces of the polishing pad 2 and the polishing head 3. In the process of contact movement of the polishing pad finishing head 401 and the polishing pad 2, not only is the roughness of the polishing pad 2 recovered, but also the polishing liquid on the polishing pad 2 is uniformly distributed, and the flatness of the polishing pad is ensured. The polishing pad cleaning head 403 can remove slurry-viscous residues of polishing particles.

The possible beneficial effects of the embodiment of the application include but are not limited to: the chemical mechanical polishing equipment can not only improve the stability of the polishing rate, but also provide multiple choices for polishing consumable maintenance, thereby better saving the consumable cost and the equipment maintenance time and increasing the productivity. Meanwhile, the dynamic selection characteristic of the plurality of polishing pad trimmers can be better suitable for different process requirements, so that the high requirements of advanced processes on flatness and accuracy can be met, and the high requirements of advanced processes on polishing rate and cleaning effect can be met.

It should be noted that, the advantages that may be generated by different embodiments may be different, and in different embodiments, the advantages that may be generated may be any one or a combination of several of the above, or any other possible advantages that may be obtained.

While the basic concepts have been described above, it will be apparent to those skilled in the art that the foregoing detailed disclosure is by way of example only and is not intended to be limiting. Although not explicitly described herein, various modifications, improvements and adaptations of the application may occur to one skilled in the art. Such modifications, improvements, and modifications are intended to be suggested within this specification, and are therefore within the spirit and scope of the exemplary embodiments of this application.

It should be noted that, in the description of the present application, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "fixed" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; the device can be rotationally connected or slidingly connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art in combination with specific cases.

In addition, when terms such as "first", "second", "third", etc. are used in the present specification to describe various features, these terms are only used to distinguish between the features, and are not to be construed as indicating or implying any association, relative importance, or implicitly indicating the number of features indicated.

In addition, the present description describes example embodiments with reference to idealized example cross-sectional and/or plan and/or perspective views. Thus, differences from the illustrated shapes, due to, for example, manufacturing techniques and/or tolerances, are to be expected. Thus, the exemplary embodiments should not be construed as limited to the shapes of regions illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the actual shape of a region of a device and are not intended to limit the scope of the exemplary embodiments.

Meanwhile, the present application uses specific words to describe the embodiments of the present specification. Reference to "one embodiment," "an embodiment," and/or "some embodiments" means that a particular feature, structure, or characteristic is associated with at least one embodiment of the application. Thus, it is emphasized and should be appreciated that two or more references to "an embodiment" or "one embodiment" or "an alternative embodiment" in various positions are not necessarily referring to the same embodiment. Furthermore, certain features, structures, or characteristics of one or more embodiments of the application may be combined as suitable.

Similarly, it should be noted that in order to simplify the description of the present disclosure and thereby aid in understanding one or more inventive embodiments, various features are sometimes grouped together in a single embodiment, figure, or description thereof. This method of disclosure does not imply that the subject application requires more features than are set forth in the claims. Indeed, less than all of the features of a single embodiment disclosed above.

Finally, it should be understood that the embodiments described herein are merely illustrative of the principles of the embodiments of the present application. Other variations are also possible within the scope of the application. Thus, by way of example, and not limitation, alternative configurations of embodiments of the application may be considered in keeping with the teachings of the application. Accordingly, the embodiments of the present application are not limited to the embodiments explicitly described and depicted herein.

Claims (7)

1. A chemical mechanical polishing apparatus, comprising:

A grinding platform;

A polishing pad mounted on the polishing platen;

The polishing device comprises a plurality of polishing pad trimmers, a plurality of polishing pad trimmers and a polishing head, wherein the polishing pad trimmers are respectively used for trimming and/or cleaning the working surface of the polishing pad during operation, the polishing pad trimmers comprise a functional head and a transmission arm, the functional head is arranged at one end of the transmission arm, and the functional head acts on the working surface of the polishing pad under the driving of the transmission arm during operation of the polishing pad trimmers to trim and/or clean the working surface of the polishing pad;

the controller is respectively and electrically connected with the polishing pad trimmers and controls the polishing pad trimmers to work, the controller controls the polishing pad trimmers to work and respectively act on different areas of the working surface of the polishing pad, and the controller controls the swinging path and/or the swinging speed of the functional head so that the polishing pad trimmers work and respectively act on different areas of the working surface of the polishing pad.

2. The chemical mechanical polishing apparatus according to claim 1, wherein the functional head is detachably connected to the actuator arm.

3. The chemical mechanical polishing apparatus according to claim 1, wherein the functional head comprises a polishing pad conditioning head and/or a polishing pad cleaning head.

4. A chemical mechanical polishing apparatus according to claim 3, wherein the polishing pad conditioner head comprises a conditioner head body and diamond abrasive grains provided on the conditioner head body.

5. A chemical mechanical polishing apparatus according to claim 3, wherein the polishing pad cleaning head comprises a cleaning head body and a cleaning brush provided on the cleaning head body.

6. The chemical mechanical polishing apparatus according to claim 1, wherein the number of the polishing pad dressers is 2 to 4.

7. The chemical mechanical polishing apparatus according to claim 1, further comprising: the grinding head drives the surface to be ground of the wafer to move relative to the surface of the grinding pad when working; and a polishing liquid supply device for supplying a polishing liquid to the polishing pad and the working surface of the polishing head.