A polishing liquid supply system and a chemical mechanical polishing system
By employing a three-way valve design and a closed-loop circuit in the polishing slurry supply system, the problem of particle aggregation caused by stagnation of polishing slurry in the pipeline was solved, thereby improving the wafer surface processing quality and yield.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHENGDU HIGH-TECH JIN SCI&TECH CO LTD
- Filing Date
- 2025-07-09
- Publication Date
- 2026-07-10
AI Technical Summary
In existing chemical mechanical polishing processes, the polishing slurry stagnates in the supply pipeline, causing particles to aggregate and form large-sized particles, resulting in scratches on the wafer surface and reducing product yield.
The three-way valve design forms a closed loop. During polishing operations, the polishing fluid is delivered to the polishing pad through the main supply pipeline. During non-operational operations, it is returned to the supply equipment through the return pipeline, ensuring that the polishing fluid is always flowing and avoiding stagnation. The flushing pipeline is used to clean the residual liquid in the pipeline and prevent particle formation.
This effectively prevents the polishing fluid from stagnating in the pipeline, inhibits the formation of large particles, and improves the quality and yield of wafer surface processing.
Smart Images
Figure CN224476042U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of chemical mechanical polishing technology, and in particular to a polishing slurry supply system and a chemical mechanical polishing system. Background Technology
[0002] Chemical mechanical polishing (CMP) is one of the five core processes in wafer fabrication. It is an ultra-precision surface finishing technology that achieves global planarization. In CMP, the wafer is typically held in place by the bottom of a polishing head, with the side of the wafer containing the deposited layer resting against the upper surface of a polishing pad. Driven by a drive assembly, the polishing head rotates in the same direction as the polishing pad, applying a downward load to the wafer. Polishing fluid is supplied to the upper surface of the polishing pad and distributed between the wafer and the pad, allowing the wafer to undergo chemical and mechanical polishing through a combination of chemical and mechanical processes.
[0003] However, in existing chemical mechanical polishing processes, the polishing slurry is delivered to the surface of the polishing pad through a supply pipeline. When the delivery equipment is not in operation, the polishing slurry stagnates inside the supply pipeline, and the stagnant slurry particles aggregate to form large particles. When subsequent polishing processes are performed, these large particles can enter the polishing area at any time, causing scratches on the wafer surface and ultimately reducing product yield. Utility Model Content
[0004] The purpose of this invention is to provide a polishing slurry supply system and a chemical mechanical polishing system to solve the problem that in the existing chemical mechanical polishing process, the polishing slurry stagnates in the supply pipeline, causing particles to agglomerate and form large-sized particles, which in turn causes scratches on the wafer surface during the polishing process and reduces the product yield.
[0005] To achieve the above objectives, this utility model provides the following technical solution:
[0006] Firstly, this utility model provides a polishing slurry supply system, including...
[0007] Polishing fluid supply equipment;
[0008] The main supply line has its input end connected to the polishing slurry supply equipment and its output end used to supply polishing slurry to the polishing pad.
[0009] The three-way valve includes a first port, a second port and a third port. The first port and the second port of the three-way valve are connected to the main supply pipeline along the flow direction of the polishing fluid. The three-way valve is used to connect the input end and the output end of the main supply pipeline when the polishing fluid is supplied.
[0010] The return line has its two ends connected to the third port of the three-way valve and the polishing fluid supply equipment, respectively. The three-way valve is used to connect the input end of the main supply line to the return line when polishing fluid is not supplied.
[0011] Optionally, in the above-mentioned polishing slurry supply system, the polishing slurry supply system further includes a flushing pipeline, one end of which is connected to a flushing slurry source, and the other end is used to supply flushing slurry to the polishing pad.
[0012] Optionally, in the above-mentioned polishing fluid supply system, the flushing pipeline also includes a flushing branch, which is connected between the output end of the main supply pipeline and the three-way valve via a switching valve, and is used to flush the part of the main supply pipeline located after the three-way valve.
[0013] Optionally, in the above-mentioned polishing slurry supply system, the polishing slurry supply system also includes a flow controller, which is located on the main supply pipeline and upstream of the three-way valve.
[0014] Optionally, in the above-mentioned polishing fluid supply system, the length of the pipeline between the three-way valve and the output end of the main supply pipeline is 0 to 100 cm.
[0015] Optionally, in the above-mentioned polishing slurry supply system, the polishing slurry supply system also includes multiple manifold valves, which are respectively connected to the main supply line, the return line and the flushing line.
[0016] Optionally, in the above-mentioned polishing slurry supply system, the inner diameter of the main supply pipeline is larger than the inner diameter of the return pipeline.
[0017] Optionally, in the above-mentioned polishing slurry supply system, the polishing slurry supply system also includes a pressure sensor, which is installed on the main supply pipeline and located upstream of the three-way valve.
[0018] Compared with the prior art, in the polishing slurry supply system provided by this utility model, the first and second ports of the three-way valve are connected to the main supply pipeline along the flow direction of the polishing slurry, while the third port is connected to the return pipeline. The two ends of the return pipeline are respectively connected to the third port of the three-way valve and the polishing slurry supply equipment, forming a closed loop. When the system is in the polishing operation state, the first and second ports of the three-way valve are connected, and the polishing slurry is directly delivered to the polishing pad through the main supply pipeline. When the system is in the non-operation state, the first and third ports of the three-way valve are connected, and the polishing slurry returns to the supply equipment through the return pipeline. This achieves the effect that the polishing slurry in the pipeline is always in a flowing state regardless of whether polishing operation is being performed, avoiding the stagnation of the polishing slurry in the pipeline, inhibiting the formation of large-sized particles, and preventing large-particle polishing slurry from contacting the wafer during polishing and causing scratch defects, thereby improving the wafer surface processing quality.
[0019] Secondly, this utility model provides a chemical mechanical polishing system, comprising:
[0020] Any of the above-mentioned polishing slurry supply systems;
[0021] Polishing equipment and polishing slurry supply systems are used to deliver polishing slurry to the polishing table.
[0022] Compared with the prior art, the beneficial effects of the chemical mechanical polishing system provided in this embodiment of the present invention are the same as those of the polishing slurry supply system described above, and will not be repeated here. Attached Figure Description
[0023] The accompanying drawings, which are included to provide a further understanding of the present invention and constitute a part of this invention, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the present invention and do not constitute an undue limitation thereof. In the drawings:
[0024] Figure 1 This is a schematic diagram of the overall structure of a polishing fluid supply system provided in an embodiment of the present invention.
[0025] Attached reference numerals: 100 is the polishing fluid supply equipment, 200 is the main supply pipeline, 300 is the three-way valve, 400 is the return pipeline, 500 is the flushing pipeline, 510 is the flushing branch, 600 is the flow controller, 700 is the manifold valve, and 800 is the polishing pad. Detailed Implementation
[0026] To make the technical problems, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.
[0027] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.
[0028] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified. "Several" means one or more, unless otherwise explicitly specified.
[0029] In the description of this utility model, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.
[0030] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0031] Firstly, please refer to Figure 1 This utility model provides a polishing slurry supply system, including a polishing slurry supply device 100, a main supply pipeline 200, a three-way valve 300, and a return pipeline 400. The input end of the main supply pipeline 200 is connected to the polishing slurry supply device 100, and the output end of the main supply pipeline 200 is used to supply polishing slurry to a polishing pad 800. The three-way valve 300 includes a first interface, a second interface, and a third interface. The first and second interfaces of the three-way valve 300 are connected to the main supply pipeline 200 along the flow direction of the polishing slurry. The three-way valve 300 is used to connect the input end and the output end of the main supply pipeline 200 when polishing slurry is supplied. The two ends of the return pipeline 400 are respectively connected to the third interface of the three-way valve 300 and the polishing slurry supply device 100. The three-way valve 300 is used to connect the input end of the main supply pipeline 200 and the return pipeline 400 when polishing slurry is not supplied.
[0032] In practical implementation: In the provided polishing slurry supply system, the first and second ports of the three-way valve 300 are connected to the main supply pipeline 200 along the flow direction of the polishing slurry, while the third port is connected to the return pipeline 400. The two ends of the return pipeline 400 are respectively connected to the third port of the three-way valve 300 and the polishing slurry supply device 100, forming a closed loop. When the system is in polishing operation mode, the first and second ports of the three-way valve 300 are connected, and the polishing slurry is directly delivered to the polishing pad 800 through the main supply pipeline 200. When the system is not in operation mode, the first and third ports of the three-way valve 300 are connected, and the polishing slurry returns to the supply device through the return pipeline 400. This achieves the effect that the polishing slurry in the pipeline is always in a flowing state regardless of whether polishing operation is being performed, avoiding stagnation of the polishing slurry in the pipeline, inhibiting the formation of large-sized particles, and preventing large-particle polishing slurry from contacting the wafer during polishing and causing scratch defects, thereby improving the surface processing quality of the wafer.
[0033] As one possible implementation, such as Figure 1 As shown, the polishing fluid supply system also includes a rinsing pipe 500. One end of the rinsing pipe 500 is connected to a fluid supply source, and the other end is used to supply rinsing fluid to the polishing pad 800. For example, the fluid supply source can be a deionized water source or a dedicated cleaning agent source. The outlet end of the rinsing pipe 500 is directly aimed at the polishing pad 800. By spraying the cleaning medium onto the polishing pad 800, the cleaning medium directly covers the surface of the polishing pad 800, effectively cleaning any unrinsed polishing fluid from the polishing pad 800 and preventing it from solidifying into larger particles. In some embodiments, a throttle valve is provided on the rinsing pipe 500. By controlling the throttle valve, the flow rate and pressure of the cleaning medium reaching the polishing pad 800 through the rinsing pipe 500 are adjusted for better cleaning of the polishing pad 800.
[0034] As one possible implementation, the flushing line 500 also includes a flushing branch 510, which is connected between the output end of the main supply line 200 and the three-way valve 300 via a switching valve. This branch is used to flush the portion of the main supply line 200 downstream of the three-way valve 300. Specifically, the flushing branch 510 is connected between the output end of the main supply line 200 and the three-way valve 300 via a switching valve. Its input end is connected to the liquid supply source of the flushing line 500, and its output end is connected to the pipe section downstream of the three-way valve 300 in the main supply line 200. This branch forms a parallel structure with the main supply line 200, and its on / off state is controlled by the switching valve.
[0035] In practice: After polishing is completed, the polishing fluid supply to the main supply line 200 is cut off. Upstream of the three-way valve 300, polishing fluid continues to flow due to the return line 400, preventing the accumulation of large particles. However, downstream of the three-way valve 300, the main supply line 200 is prone to large particle accumulation due to the lack of polishing fluid flow. At this point, the switch valve of the flushing branch 510 is opened, allowing flushing fluid to flow from the supply source into the flushing branch 510 and be directed into the downstream section of the main supply line 200. The flushing fluid flows along the pipeline to the polishing pad 800, flushing away residual polishing fluid and removing easily deposited polishing fluid particles from the downstream section of the three-way valve 300. This setup, through directional flushing of the downstream section of the three-way valve 300, solves the problem of particle accumulation caused by polishing fluid stagnation in that area, avoids pipeline blockage and the risk of large particles scratching the wafer surface during restart, and improves the uniformity of wafer surface flatness.
[0036] In some embodiments, the polishing slurry supply system further includes a flow controller 600, which is located on the main supply line 200 and upstream of the three-way valve 300. Its input receives the polishing slurry flow from upstream. As the polishing slurry flows through the main supply line 200, the flow controller 600 adjusts the flow path cross-sectional area via an internal regulating structure, which can be a deformable tube or valve opening. This precise flow control solves the problem of uneven polishing slurry supply caused by pressure fluctuations or changes in pipeline resistance, ensuring consistent polishing slurry distribution on the polishing pad 800 surface, while avoiding waste caused by excessive supply and reducing production costs.
[0037] As one possible implementation, the length of the pipeline between the three-way valve 300 and the output end of the main supply line 200 is 0–100 cm. For example, it can be any length within the range of 10 cm, 30 cm, 50 cm, 70 cm, 90 cm, 100 cm, or 0–100 cm. This setting limits the pipeline length between the three-way valve 300 and the main supply line 200 to below 100 cm. If the length exceeds 100 cm, the polishing slurry will remain in the pipeline for a longer period, increasing the risk of particle aggregation and potentially causing large particles to scratch the wafer surface upon restart. In practice, during polishing operations, when the three-way valve 300 switches to the reflux state, the polishing slurry returns to the polishing slurry supply equipment 100 via the reflux pipeline 400. At this time, the short pipeline within 100 cm downstream of the three-way valve 300, due to its small volume and short flow path, allows residual polishing slurry to be quickly cleaned by the cleaning fluid, preventing polishing slurry from accumulating in the area downstream of the three-way valve 300.
[0038] As one possible implementation, the polishing fluid supply system also includes multiple manifold valves 700, which are respectively connected to the main supply line 200, the return line 400 and the flushing line 500.
[0039] As one possible implementation, multiple manifold valves 700 are respectively connected to the main supply line 200, the return line 400 and the flushing line 500 to form a parallel fluid control hub.
[0040] Specifically, when the system needs to switch between polishing, reflux, or rinsing modes, the flow direction and flow rate of the fluid are distributed by adjusting the valve core opening of each manifold valve 700. For example, during polishing, the manifold valve 700 of the main supply line 200 is opened to its maximum opening, while the manifold valves 700 of the reflux and rinsing lines 500 are closed to ensure efficient delivery of polishing fluid to the polishing pad 800. When switching to rinsing mode, the manifold valve 700 of the main supply line 200 is closed, and the manifold valve 700 of the rinsing line 500 is opened, allowing the rinsing fluid to flush away residual polishing fluid from the lines. In reflux mode, the manifold valve 700 of the reflux line 400 is opened to guide unused polishing fluid back to the polishing fluid supply device 100. The coordinated operation of each manifold valve 700 is achieved through linkage via a controller to avoid fluid path conflicts. By adding a manifold valve 700 to the main supply, return and flushing pipeline 500, precise isolation and dynamic switching of the fluid path are achieved, solving the problem of particle sedimentation and cross-contamination caused by the stagnation of polishing fluid in traditional single pipelines.
[0041] As one possible implementation, the inner diameter of the main supply line 200 is larger than that of the return line 400. During polishing, an external pump injects polishing slurry into the main supply line 200, ensuring a stable high-flow-rate delivery of polishing slurry to the polishing pad 800. When the system switches to return mode, the polishing slurry in the main supply line 200 enters the smaller-diameter return line 400 under pressure. Due to the reduced cross-sectional area of the return line 400, the hydraulic pressure in the return line 400 is sufficiently high to smoothly return the polishing slurry. The velocity and pressure differences created by the difference in pipe diameter solve the problem of polishing slurry residue caused by insufficient flow rate in traditional equal-diameter return systems.
[0042] As one possible implementation, the polishing slurry supply system also includes a pressure sensor, which is located on the main supply line 200 and upstream of the three-way valve 300. By placing the pressure sensor upstream of the three-way valve 300 in the main supply line 200, and by monitoring the pressure in the line in real time, upstream equipment failures, such as external pump failures, can be immediately located, thus preventing wafer scratches caused by interruptions in the downstream polishing slurry supply due to abnormal pressure.
[0043] Secondly, this utility model provides a chemical mechanical polishing system, including any of the above-mentioned polishing slurry supply systems and polishing equipment, wherein the polishing slurry supply system is used to deliver polishing slurry to the polishing table.
[0044] Compared with the prior art, the beneficial effects of the chemical mechanical polishing system provided in this embodiment of the present invention are the same as those of the polishing slurry supply system described above, and will not be repeated here.
[0045] Although the present invention has been described herein in conjunction with various embodiments, those skilled in the art will understand and implement other variations of the disclosed embodiments by reviewing the accompanying drawings, the disclosure, and the appended claims in carrying out the claimed invention. In the claims, the word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude a plurality. A single processor or other unit can implement several functions listed in the claims. While different dependent claims may recite certain measures, this does not mean that these measures cannot be combined to produce good results.
[0046] Although the present invention has been described in conjunction with specific features and embodiments, it is obvious that various modifications and combinations can be made therein without departing from the spirit and scope of the present invention. Accordingly, this specification and drawings are merely exemplary descriptions of the present invention as defined by the appended claims, and are considered to cover any and all modifications, variations, combinations, or equivalents within the scope of the present invention. Clearly, those skilled in the art can make various alterations and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such modifications and modifications of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention also intends to include such modifications and modifications.
Claims
1. A polishing liquid supply system characterized by comprising: include: Polishing fluid supply equipment; The main supply pipeline has its input end connected to the polishing fluid supply equipment and its output end used to supply polishing fluid to the polishing pad. A three-way valve, comprising a first port, a second port, and a third port, wherein the first and second ports of the three-way valve are connected to the main supply pipeline along the flow direction of the polishing fluid, and the three-way valve is used to connect the input end and the output end of the main supply pipeline when supplying polishing fluid; The return pipeline has its two ends connected to the third port of the three-way valve and the polishing fluid supply device, respectively. The three-way valve is used to connect the input end of the main supply pipeline to the return pipeline when the polishing fluid is not supplied.
2. The polishing slurry supply system according to claim 1, characterized in that, The polishing fluid supply system also includes a flushing pipeline, one end of which is connected to a flushing fluid source, and the other end is used to supply flushing fluid to the polishing pad.
3. The polishing slurry supply system according to claim 2, characterized in that, The flushing pipeline also includes a flushing branch, which is connected between the output end of the main supply pipeline and the three-way valve via a switching valve, and is used to flush the portion of the main supply pipeline located after the three-way valve.
4. The polishing slurry supply system according to claim 1, characterized in that, The polishing fluid supply system also includes a flow controller, which is located on the main supply pipeline and upstream of the three-way valve.
5. The polishing slurry supply system according to claim 1, characterized in that, The length of the pipeline between the three-way valve and the output end of the main supply pipeline is 0-100cm.
6. The polishing slurry supply system according to claim 2, characterized in that, The polishing fluid supply system also includes multiple manifold valves, which are respectively connected to the main supply line, the return line, and the flushing line.
7. The polishing slurry supply system according to claim 1, characterized in that, The inner diameter of the main supply pipeline is larger than the inner diameter of the return pipeline.
8. The polishing slurry supply system according to claim 1, characterized in that, The polishing fluid supply system also includes a pressure sensor, which is located on the main supply pipeline and upstream of the three-way valve.
9. A chemical mechanical polishing system, characterized in that, include: The polishing slurry supply system as described in any one of claims 1-8; Polishing equipment, wherein the polishing slurry supply system is used to deliver polishing slurry to the polishing table.