Grinding pad trimming device
By installing multiple dressers on the swing arm of the CMP equipment, the problem of uneven surface of the grinding pads was solved, enabling a more efficient and stable dressing process, extending the service life of the grinding pads and reducing maintenance costs.
Patent Information
- Application Number
- CN202520433191.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-12
- Publication Date
- 2026-01-23
- Estimated Expiration
- 2035-03-12
AI Technical Summary
In existing CMP equipment, the grinding pad dressing process suffers from uneven surface due to the limited range of motion of the swing arm of a single dresser, which affects the wafer grinding quality and shortens the lifespan of the grinding pad.
By using a configuration that mounts multiple dressers on the swing arm, the dressers can simultaneously cover different areas of the grinding pad, eliminating the need for the swing arm to swing over a wide range. The coordinated work of multiple dressers achieves more uniform dressing.
It improves dressing efficiency, reduces vibration and positional deviation, enhances dressing accuracy and consistency, extends the service life of the grinding pad, and reduces equipment maintenance costs.
Smart Images
Figure CN223820329U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the technical field of semiconductor manufacturing, especially relates to a kind of polishing pad finishing device capable of prolonging laser head service life. BACKGROUND
[0002] Chemical mechanical polishing (CMP) is a processing method for eliminating wafer surface material by chemical force and mechanical force mixing, and is widely used in surface processing technology.
[0003] As shown in Figure 1 The polishing part of the existing CMP equipment includes a polishing pad 10, a polishing head 19, a polishing liquid delivery arm 18 and a finishing device 12. The CMP technology is similar to the general metal type polishing process. The back surface of the wafer is vacuum adsorbed on the polishing head 19. The polishing head 19 is driven by an electric motor to rotate at a certain angular velocity. The polishing pad 10 is also driven by an electric motor to rotate at a certain angular velocity. The rotation speed of the polishing head 19 and the polishing pad 10 is approximately the same. The polishing liquid is transmitted to the surface of the polishing pad 10 at a certain flow rate through the transmission action of the polishing liquid delivery arm 18. The polishing liquid is distributed on the surface of the polishing pad 10 through the centrifugal force of the rotation of the polishing pad 10 and the swing action of the polishing liquid delivery arm 18. The finishing device 12 is usually configured with a swing arm 122 and a finisher 123. The function of the finisher 123 is to continuously rub the surface of the polishing pad 10, which improves the surface topography of the polishing pad 10. In order to cover the entire surface of the polishing pad 10, the swing arm 122 needs to move back and forth between the edge and the center of the polishing pad 10.
[0004] Generally speaking, the rotation speed and the pressing force of the finisher are the key parameters in the chemical mechanical polishing process. The greater the rotation speed and the pressing force, the greater the ability to change the surface topography of the polishing pad. When the rotation speed and the pressing force are too large, the surface topography groove of the polishing pad is ground flat, and the service life of the polishing pad reaches the end. SUMMARY
[0005] The technical problem to be solved by the utility model is to provide a polishing pad finishing device, which can improve the flatness of the polishing pad finishing.
[0006] In order to solve the above problems, the utility model provides a polishing pad finishing device, which comprises: a fixed support, which is fixedly arranged at the edge of a polishing pad, and has a spacing between the fixed support and the polishing pad; a swing arm, whose first end is fixedly connected to the fixed support, and whose second end can extend above the polishing pad, and the swing arm can sweep around the fixed support; and a plurality of finishers, which are connected to the swing arm and can finish the surface of the polishing pad under the driving of the swing arm.
[0007] In some embodiments, the second end of the swing arm is capable of extending above the center of the polishing pad.
[0008] In some embodiments, the length of the arrangement of the plurality of trimmers is greater than the radius of the polishing pad.
[0009] In some embodiments, the trimmer comprises a connecting handle detachably fixed to the swing arm, and a trimming head connected to the connecting handle and capable of self-rotation to trim the surface of the polishing pad.
[0010] In some embodiments, the connecting handle is fixedly sleeved on the swing arm.
[0011] In some embodiments, the plurality of trimmers are evenly distributed along the extension direction of the swing arm.
[0012] In some embodiments, the number of the trimmers is four.
[0013] In some embodiments, the trimmer comprises a diamond trimmer.
[0014] In some embodiments, the rotation speed of the trimmer is adjustable, and / or the pressure of the trimmer is adjustable.
[0015] In some embodiments, the plurality of trimmers are independently adjustable.
[0016] The above technical solution has the following advantages: (1) improved trimming efficiency: the plurality of trimmers can work simultaneously, covering different areas of the polishing pad, without frequent movement of the swing arm, thus greatly shortening the trimming time and improving the overall efficiency of the CMP process; (2) eliminating swing arm movement interference: since the swing arm does not need to swing in a large range, vibration and position deviation caused by movement are reduced, making the trimming process more stable, reducing equipment maintenance cost, improving running stability, and improving trimming precision and consistency; (3) precise trimming: the trimming area covered by the trimmer on the polishing pad is increased, which can more evenly trim the surface of the polishing pad, avoiding local excessive wear. BRIEF DESCRIPTION OF DRAWINGS
[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments of the present application. Obviously, the drawings described in the following are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.
[0018] Figure 1 is a schematic view of the polishing part of the existing CMP equipment;
[0019] Figure 2 This is a top view schematic diagram of an embodiment of the grinding pad trimming device provided by the present invention;
[0020] Figure 3 This is a side view of an embodiment of the grinding pad trimming device provided by the present invention;
[0021] Figure 4 This is a schematic diagram simulating the running trajectory of different numbers of trimmers according to an embodiment of the present invention.
[0022] Explanation of reference numerals in the attached figures:
[0023] 10 Grinding pad 19 Grinding head 18 Grinding fluid transfer arm
[0024] 12 Dressing device 122 Swing arm 123 Dresser
[0025] 20 Grinding pad 21 Fixing bracket
[0026] 22 swing arm 221 first end 222 second end
[0027] 23 Dresser 231 Connecting handle 232 Dressing head Detailed Implementation
[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.
[0029] In chemical mechanical polishing (CMP) processes, the traditional configuration typically involves a swing arm paired with a dresser. To cover the entire surface of the polishing pad, the swing arm needs to move back and forth between the edge and center of the pad. While this method achieves pad dressing, the swing arm requires a large range of motion to accommodate the dresser's movements. Furthermore, balancing the pad's rotation and the swing arm's movement is difficult, leading to increasing surface unevenness over time and significantly impacting wafer polishing quality. Additionally, the limited range of motion of the swing arm means that a single dresser may result in insufficient or uneven dressing in certain areas. Therefore, this invention proposes an improved polishing pad dressing device to enhance the stability of the dresser's pad dressing process.
[0030] Please refer to the following: Figures 2-3 ,in, Figure 2 This is a top view schematic diagram of an embodiment of the grinding pad dressing device provided by the present invention.Figure 3 This is a side view of an embodiment of the grinding pad trimming device provided by the present invention.
[0031] like Figures 2-3 As shown, the polishing pad dressing device described in this embodiment includes: a fixed bracket 21, a swing arm 22, and multiple dressing devices 23. The fixed bracket 21 is fixedly disposed on the edge of the polishing pad 20, and there is a distance W between the fixed bracket 21 and the polishing pad 20; that is, the fixed bracket 21 does not contact the polishing pad 20. The first end 221 of the swing arm 22 is fixedly connected to the fixed bracket 21, and the second end 222 of the swing arm 22 can extend above the polishing pad 20. The swing arm 22 can sweep horizontally around the fixed bracket 21. The multiple dressing devices 23 are all connected to the swing arm 22 and can dress the surface of the polishing pad 20 under the action of the swing arm 22.
[0032] By installing multiple dressers on the swing arm, these dressers can work simultaneously, covering different areas of the grinding pad. This significantly reduces dressing time and improves the overall efficiency of the CMP process. Since the swing arm does not require extensive swinging, vibration and positional deviation caused by movement are reduced, making the dressing process more stable, lowering equipment maintenance costs, improving operational stability, and enhancing dressing accuracy and consistency. The multi-dresser configuration allows for more even dressing of the grinding pad surface, preventing excessive localized wear and extending the pad's lifespan, thus reducing replacement frequency and costs.
[0033] In this embodiment, the second end 222 of the swing arm 22 can extend above the center of the polishing pad 20. Therefore, when the swing arm 22 sweeps across the area above the center of the polishing pad 20, the outermost trimmer 23, away from the fixed support 21, can trim the surface of the central region of the polishing pad 20, increasing the trimming area coverage of the trimmer on the polishing pad and improving trimming accuracy. In some embodiments, the length of the orthographic projection of the swing arm 22 onto the polishing pad 20 is greater than the radius of the polishing pad 20. Therefore, when the swing arm 22 sweeps across the area above the center of the polishing pad 20, the edge of the outermost trimmer 23, away from the fixed support 21, can extend beyond the center of the polishing pad 20 by a certain distance (e.g., approximately 5 mm) in a direction away from the fixed support 21.
[0034] In this embodiment, the length L of the arrangement of the plurality of trimmers 23 is greater than the radius R of the polishing pad. Therefore, when the swing arm 22 sweeps horizontally above the center of the polishing pad 20, the innermost trimmer 23 located near the fixed support 21 can trim the surface of the edge area of the polishing pad 20, while the outermost trimmer 23 located away from the fixed support 21 can trim the surface of the central area of the polishing pad 20. This increases the trimming area coverage of the trimmers on the polishing pad, improving trimming accuracy and consistency, and allowing for more uniform trimming of the polishing pad surface, avoiding excessive local wear. Specifically, the length L of the arrangement of the plurality of trimmers 23 is the distance between the edge of the innermost trimmer 23 near the fixed support 21 and the edge of the outermost trimmer 23 away from the fixed support 21.
[0035] In this embodiment, the trimmer 23 includes a connecting handle 231 and a trimming head 232. The connecting handle 231 is detachably and fixedly connected to the swing arm 22, thus enabling it to move with the swing arm 22. The trimming head 232 is connected to the connecting handle 231 and is capable of rotation to trim the surface of the polishing pad 20. Furthermore, the connecting handle 231 is sleeved and fixed onto the swing arm 22.
[0036] In this embodiment, the plurality of dressers 23 are evenly distributed along the extension direction of the swing arm 22, which can more evenly dress the surface of the grinding pad and avoid excessive local wear. In this embodiment, the number of dressers 23 is four. The four dressers 23 are evenly distributed along the extension direction of the swing arm 22, which can more evenly dress the surface of the grinding pad.
[0037] In this embodiment, the dresser 23 includes a diamond dresser. The dressing head of the diamond dresser is a metal disc with diamond particles attached to its surface. Its function is to continuously rub the surface of the polishing pad, thereby improving the surface morphology of the polishing pad. During the CMP process, the surface of the polishing pad becomes uneven due to wear and the accumulation of polishing byproducts, affecting the polishing effect. Through the horizontal sweeping of the swing arm and the rotation of the diamond dresser, the uneven parts and residues on the surface of the polishing pad are removed, restoring its roughness, ensuring the uniformity and stability of the polishing process, maintaining the stable surface state of the polishing pad, and ensuring consistent polishing results.
[0038] In some embodiments, the rotational speed of the dresser 23 is adjustable, and / or the pressure of the dresser 23 is adjustable. Depending on process requirements, with other hardware parameters fixed, simply increasing or decreasing the dresser's rotational speed and / or pressure can find the optimal adjustment window for the dresser, ensuring the uniformity and stability of the grinding process, maintaining a stable surface condition of the grinding pad, and ensuring consistent grinding results.
[0039] In some embodiments, the plurality of trimmers 23 can be adjusted independently. The rotation speed, pressure, and other parameters of each trimmer can be flexibly and independently adjusted according to different process requirements, so as to perform precise trimming and local optimization on specific areas of the polishing pad, thereby improving the adaptability of the polishing pad trimming device described in this embodiment in semiconductor manufacturing and optical component processing with high precision requirements.
[0040] Specifically, when the dresser 23 is working, the polishing pad 20 is also rotating, ensuring that the entire polishing pad 20 is dressed by the dresser 23. The polishing pad 20 can be driven by an electric motor to rotate at a certain angular velocity, and the swing arm 22 can also be driven by an electric motor to sweep at a certain frequency, thereby moving the dresser 23. The dresser 23 can also be driven by an electric motor to rotate at a certain angular velocity.
[0041] Please see Figure 4 This is a schematic diagram simulating the running trajectory of a grinding pad dressing device using different numbers of dressers, provided in one embodiment of this utility model. Taking an AMAT machine as an example, software is used to simulate a 5-second running trajectory for the grinding pad dressing device using different numbers of dressers. Figure 4 Part (a) shows a simulated operational trajectory of an existing grinding pad dressing device using a single dresser; part (b) shows a simulated operational trajectory of a grinding pad dressing device using two dressers; part (c) shows a simulated operational trajectory of a grinding pad dressing device using three dressers; and part (d) shows a simulated operational trajectory of a grinding pad dressing device using four dressers. The numbers in the figures are coordinate values (in cm). The dresser's rotation speed is 60 rpm (revolutions per minute), the grinding pad's rotation speed is 60 rpm, and the swing arm's sweeping frequency is 13 swings per minute. Figure 4 The effect of the adjustment and optimization can be seen intuitively, and the simulated path shows that the grinding pad dressing device with 4 dressingers on the swing arm has a more uniform performance.
[0042] This utility model has the following significant advantages through the configuration of installing multiple dressers on the swing arm: (1) Improved dressing efficiency: Multiple dressers can work simultaneously, covering different areas of the grinding pad, eliminating the need for frequent swing arm movement, which also significantly shortens the dressing time and improves the overall efficiency of the CMP process. (2) Elimination of swing arm movement interference: Since the swing arm does not need to swing over a large range, it reduces vibration and positional deviation caused by movement, making the dressing process more stable, reducing equipment maintenance costs, improving operational stability, and improving dressing accuracy and consistency. (3) Precise dressing: The dressing area of the dresser on the grinding pad is increased, which can more evenly dress the surface of the grinding pad and avoid localized excessive wear.
[0043] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "also includes a…" does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.
[0044] The above description is merely a preferred embodiment of this utility model and is not intended to limit the scope of protection of this utility model. It should be noted that those skilled in the art can make several improvements and modifications without departing from the principle of this utility model, and these improvements and modifications should also be considered within the scope of protection of this utility model.
Claims
1. A grinding pad dressing device, characterized in that, include: A fixed bracket is fixedly disposed on the edge of the grinding pad, and there is a gap between the fixed bracket and the grinding pad; A swing arm, the first end of which is fixedly connected to the fixed bracket, and the second end of which can extend above the grinding pad, the swing arm can sweep horizontally around the fixed bracket; Multiple dressing devices are connected to the swing arm and can dress the surface of the grinding pad under the action of the swing arm.
2. The grinding pad dressing device according to claim 1, characterized in that, The second end of the swing arm can extend above the center of the grinding pad.
3. The grinding pad dressing device according to claim 1, characterized in that, The length of the arrangement of the plurality of trimmers is greater than the radius of the abrasive pad.
4. The grinding pad dressing device according to claim 1, characterized in that, The trimmer includes: a connecting handle, which is detachably and fixedly connected to the swing arm; A trimming head, connected to the connecting handle, is capable of rotating to trim the surface of the abrasive pad.
5. The grinding pad dressing device according to claim 4, characterized in that, The connecting handle is sleeved and fixed onto the swing arm.
6. The grinding pad dressing device according to claim 1, characterized in that, The plurality of trimmers are evenly distributed along the extension direction of the swing arm.
7. The grinding pad dressing device according to claim 1, characterized in that, The number of trimmers is 4.
8. The grinding pad dressing device according to claim 1, characterized in that, The finishing tool includes a diamond finishing tool.
9. The grinding pad dressing device according to claim 1, characterized in that, The speed of the dresser is adjustable, and / or the pressure of the dresser is adjustable.
10. The grinding pad dressing device according to claim 1, characterized in that, Multiple trimmers can be adjusted independently.