Retaining ring and polishing head

Abstract

The application discloses a holding ring and a polishing head, and the holding ring comprises a base body and a detachable sub-body; the base body and the sub-body are annular structures; the first end of the base body is configured to be connected with the polishing head; the first end of the sub-body is connected with the base body, and the second end of the sub-body is located in the same plane with the second end of the base body; the base body and the sub-body are used for applying pressure to the polishing pad during the process that the polishing head places a wafer on the polishing pad to polish the wafer. According to the detachable sub-body, the contact area of the holding ring and the polishing pad can be adaptively changed according to the polishing requirement of wafers with different specifications, so that the polishing effect of the wafer can be ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of chemical mechanical polishing, and in particular to a retaining ring and a polishing head. BACKGROUND

[0002] A chemical mechanical polishing (CMP) device mainly carries a wafer to a polishing pad by a polishing head, and completes the planarization of the wafer surface under the joint action of mechanical friction and chemical reaction. In order to improve the adsorption of the polishing head to the wafer, a retaining ring is usually arranged outside the polishing head to increase the pressure of the polishing head to the polishing pad to retain the wafer. The pressure of the polishing head to the polishing pad through the retaining ring is negatively correlated with the risk of a polishing process.

[0003] At present, in order to ensure the stability of the wafer processing process, the pressure of the retaining ring to the polishing pad is adjusted by adjusting the pressure of the retaining ring in the polishing head chamber. However, the pressure of the retaining ring to the retaining ring is different for different types of wafers. SUMMARY

[0004] Therefore, the present application provides a retaining ring and a polishing head to at least partially solve the above technical problems.

[0005] The first aspect of the present application provides a retaining ring applied to a polishing head, comprising: a base body and a separate body separable from the base body; the base body and the separate body are both annular structures, a first end of the base body is configured to be connected with the polishing head, and a second end of the separate body is located in the same plane with a second end of the base body after the first end of the separate body is connected with the base body; the base body and the separate body are used to apply pressure to the polishing pad in a process in which the polishing head places a wafer on the polishing pad to polish the wafer.

[0006] Optionally, at least two through holes are arranged on the base body along the center line direction of the base body; at least two internal thread holes are arranged on the first end of the separate body along the center direction of the separate body, and the internal thread holes correspond to the through holes one by one; the base body and the separate body are connected by bolts threaded through the through holes and the internal thread holes.

[0007] Optionally, the retaining ring further comprises at least two elastic plugs; the elastic plugs are used to plug the through holes when the separate body is separated from the base body, wherein the elastic plugs and the through holes are connected by interference fit, and different through holes are plugged by different elastic plugs.

[0008] Optionally, the base body is provided with at least one positioning pin, and the first end of the split body is provided with at least one pin hole; after the base body is connected with the split body, one positioning pin is embedded in each pin hole, and different positioning pins are embedded in different pin holes.

[0009] Optionally, the second end of the base body is provided with a first groove, and the second end of the split body is provided with a second groove; after the first end of the split body is connected with the base body, the first groove and the second groove are in communication; the first groove and the second groove are used to guide the polishing liquid below the polishing head during polishing of the wafer.

[0010] Optionally, the number of the first grooves is the same as the number of the second grooves; after the first end of the split body is connected with the base body, each first groove is in communication with one second groove, and the abutting surfaces of the first groove and the second groove in communication have the same size and shape.

[0011] Optionally, the base body is provided with a plurality of positioning pins, and the first end of the split body is provided with a plurality of pin holes; the plurality of positioning pins include a target positioning pin, and the target positioning pin has a size and / or cross-sectional shape different from those of other positioning pins; the plurality of pin holes include a target pin hole, and the target pin hole has a size and / or cross-sectional shape different from those of other pin holes; when the base body is connected with the split body, the target positioning pin is embedded in the target pin hole, so that each first groove is in communication with one second groove and the axes thereof coincide.

[0012] Optionally, the axes of the first grooves and the second grooves are straight lines, and the radii of the first grooves and the second grooves are the same.

[0013] Optionally, the axes of the first grooves and the second grooves are straight lines, and the radii of at least one of the first grooves and the second grooves linearly increase along the positive direction of the axis after the first grooves and the second grooves are in communication.

[0014] Optionally, the ratio of the number of the second grooves to the number of the first grooves ranges from 1.5 to 2.5.

[0015] Optionally, a first concave circular-arc chamfer is arranged along the outer edge of the second end of the base body, and a second concave circular-arc chamfer is arranged along the inner edge of the second end of the split body; after the base body is connected with the split body, the first concave circular-arc chamfer and the second concave circular-arc chamfer are spliced into a converging groove, and the first grooves and the second grooves are in communication with the converging groove.

[0016] Optionally, a ratio of a difference between the outer radius and the inner radius of the second end of the base body and a difference between the outer radius and the inner radius of the second end of the separate body ranges from 0.5 to 2.

[0017] Optionally, at least part of the inner side wall of the separate body is a conical surface, and an included angle between the conical inner side wall and the center line of the separate body ranges from 75° to 85°.

[0018] Optionally, the inner side wall of the separate body adjacent to the first end of the separate body is a conical surface, the inner side wall of the separate body adjacent to the second end of the separate body is a cylindrical surface, and the conical inner side wall of the separate body intersects with the cylindrical inner side wall of the separate body.

[0019] Optionally, the base body is made of polyether ether ketone material, and the separate body is made of polyphenylene sulfide material.

[0020] The second aspect of the present application provides a carrier head for chemical mechanical polishing, which comprises the retaining ring described above.

[0021] The present application can adaptively change the contact area of the retaining ring and the polishing pad according to the demand of polishing wafers of different specifications, and then provide corresponding pressure through the retaining ring when polishing wafers of different models, so as to ensure the polishing effect on the wafers. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments described in the embodiments of the present application, and other drawings can also be obtained by those skilled in the art according to these drawings.

[0023] Figure 1 is a schematic diagram of an exemplary scenario suitable for the embodiments of the present application;

[0024] Figure 2 is a schematic diagram of a retaining ring of an embodiment of the present application;

[0025] Figure 3 is a schematic diagram of a retaining ring including a through hole of an embodiment of the present application;

[0026] Figure 4 is a schematic diagram of a retaining ring including an elastic plug of an embodiment of the present application;

[0027] Figure 5 is a schematic diagram of a retaining ring including a positioning pin of an embodiment of the present application;

[0028] Figure 6 is a schematic view of a retaining ring including first grooves according to an embodiment of the present application;

[0029] Figure 7 is a schematic view of a retaining ring including first grooves according to another embodiment of the present application;

[0030] Figure 8 is a schematic view of a retaining ring including a flow channel according to an embodiment of the present application. DETAILED DESCRIPTION

[0031] In order to make personnel in the art better understand the technical solutions in the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative work should belong to the scope of protection of the embodiments of the present application.

[0032] The terms used in the present application are merely for the purpose of describing particular embodiments and are not intended to limit the present application. The singular forms "a", "an" and "the" used in the present application and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0033] It should be understood that although the terms first, second, third, etc. can be used in this application to describe various information, these information should not be limited to these terms. These terms are only used to distinguish one type of information from another type of information. For example, without departing from the scope of the present application, the first information can also be referred to as the second information, and similarly, the second information can also be referred to as the first information. Depending on the context, the word "if" as used herein can be interpreted as "when" or "upon determination" or "in response to determining".

[0034] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work should belong to the scope of protection of the present application. In the case of no conflict, each of the following embodiments and its technical features can be combined with each other.

[0035] Figure 1 A schematic view of an exemplary scenario applicable to embodiments of the present application is shown in Figure 1As shown in the embodiment of this application, the retaining ring 1 is applied to the polishing head 2. During the polishing process, the polishing head 2 loads the wafer to be polished and abuts it against the polishing pad 3 above the polishing disk 6. During the polishing process, the liquid supply device 4 supplies polishing liquid to the polishing pad 3. The polishing liquid flows between the wafer and the polishing pad 3 to aid in polishing. A dresser 5 is also present during the polishing process to dress the surface of the polishing pad 3.

[0036] During the polishing process, the wafer is located inside the holding ring 1, which is used to apply pressure to the polishing pad 3 around the wafer. However, different wafer sizes require different pressure values ​​at the contact point between the holding ring 1 and the polishing pad. Some require a small pressure range, while others require a large pressure range. If the holding ring 1 is of the same specification, the polishing effect on wafers of different sizes will not be uniform. If different specifications of holding ring 1 are manufactured for wafers of different sizes, the production cost will be high. Therefore, based on the above exemplary scenario, this application provides a holding ring to at least partially solve the above problems.

[0037] Figure 2 This is a schematic diagram of a retaining ring according to an embodiment of this application. Figure 2 As shown, the retaining ring 1 used in the polishing head 2 includes a base 10 and a separable part 20. Both the base 10 and the part 20 are annular structures. The first end of the base 10 is configured to connect to the polishing head 2. After the first end of the part 20 is connected to the base 10, the second end of the part 20 and the second end of the base 10 are located in the same plane. The base 10 and the part 20 are used to apply pressure to the polishing pad 3 during the process of the polishing head 2 placing the wafer on the polishing pad 3 for polishing.

[0038] To polish wafers of different specifications, the retaining ring 1 may include a separable part 20 of the substrate 10. When the wafer requires the retaining ring 1 to apply pressure to a larger area of ​​the polishing pad 3, the part 20 is connected to the substrate 10, increasing the contact area between the retaining ring 1 and the polishing pad 3 and reducing the pressure at the contact point. When the wafer requires the retaining ring 1 to apply pressure to a smaller area of ​​the polishing pad 3, the part 20 is separated from the substrate 10. In this case, the retaining ring 1 includes the substrate 10 but does not include the part 20, thereby reducing the contact area between the retaining ring 1 and the polishing pad 3 and increasing the pressure at the contact point. This solution is particularly suitable for polishing third-generation semiconductors such as silicon carbide.

[0039] Specifically, the ratio of the difference between the outer and inner radii of the second end of the base 10 to the difference between the outer and inner radii of the second end of the split body 20 ranges from 0.5 to 2.

[0040] Since the sub-body 20 is detachable, different specifications of the sub-body 20 can be made, the size of the second end of the sub-body 20 is changed, that is, the difference between the outer circle radius and the inner circle radius of the second end of the sub-body 20 is changed, and then more specifications of the wafer can be adapted.

[0041] Specifically, at least part of the inner side wall of the sub-body 20 is a conical surface, the inner side wall with the conical surface is adjacent to the first end of the sub-body 20, and the included angle between the inner side wall with the conical surface and the center line of the sub-body 20 is in the range of 75°-85°.

[0042] The inner side wall with the conical surface of the sub-body 20 is adjacent to the first end of the sub-body 20, and the included angle between the inner side wall with the conical surface and the center line of the sub-body 20 is in the range of 75°-85°, that is, the conical surface angle of the surface of the sub-body 20 opposite to the base body 10 except the first end is 95°-105°. At this time, if the polishing liquid flows between the base body 10 and the sub-body 20, it will also flow down along the conical surface under the action of gravity, and it is not easy to cause the polishing liquid to accumulate.

[0043] Specifically, the inner side wall adjacent to the first end of the sub-body 20 on the sub-body 20 is a conical surface, the inner side wall adjacent to the second end of the sub-body 20 on the sub-body 20 is a cylindrical surface, and the inner side wall with the conical surface on the sub-body 20 intersects with the inner side wall with the cylindrical surface.

[0044] The inner side wall of the sub-body 20 can also include a cylindrical surface, which can further facilitate the installation of the base body 10 and the sub-body 20.

[0045] Specifically, the base body 10 is made of polyether ether ketone material, and the sub-body 20 is made of polyphenylene sulfide material.

[0046] Since the wear amounts of the inner side and the outer side of the retaining ring 1 are different in the actual polishing process, and the inner side wear amount is actually greater than the outer side wear amount, by making the base body 10 adopt the polyether ether ketone material with higher wear resistance and the sub-body 20 adopt the polyphenylene sulfide material with slightly lower wear resistance but lower cost, the polishing effect can be ensured while the production cost is reduced.

[0047] In the embodiment of the present application, by setting the detachable sub-body 20, the contact area of the retaining ring 1 and the polishing pad 3 can be adaptively changed according to the demand of polishing different specifications of wafers, and then the polishing effect on the wafers can be ensured.

[0048] Figure 3 is a schematic view of a retaining ring including a through hole according to an embodiment of the present application, as Figure 3 At least two through holes are provided on the base body 10 in the direction of the center line of the base body 10. At least two inner threaded holes are provided on the first end of the sub-body 20 in the center direction of the sub-body 20, and the inner threaded holes correspond to the through holes one by one. The base body 10 and the sub-body 20 are connected by a bolt 30 threaded through the through hole and the inner threaded hole.

[0049] The base body 10 and the split body 20 can be connected by the bolts 30, at least two through holes are arranged on the base body 10 along the center line direction of the base body 10, at least two inner threaded holes are arranged on the first end of the split body 20 along the center direction of the split body 20, in the installation, first, the inner threaded holes are aligned with the through holes one by one, then the bolts 30 which are the same number as the through holes are passed through the through holes, and then are screwed with the inner threaded holes, thereby connecting the base body 10 and the split body 20.

[0050] In the embodiment of the present application, the base body 10 and the split body 20 are connected by the bolts 30, which can ensure the connection strength of the base body 10 and the split body 20, and facilitate the disassembly of the split body 20.

[0051] Figure 4 is a schematic view of a retaining ring including elastic plugs according to an embodiment of the present application, as shown in Figure 4 The retaining ring 1 further includes at least two elastic plugs 40. The elastic plugs 40 are used to plug the through holes when the split body 20 is separated from the base body 10, wherein the elastic plugs 40 are connected with the through holes by interference fit, and different through holes are plugged by different elastic plugs 40.

[0052] When the split body 20 is separated from the base body 10, the bolts 30 will also be taken out of the through holes of the base body 10, at this time, polishing is performed, and the polishing liquid may flow into the through holes, causing damage to the base body 10. Therefore, by arranging the elastic plugs 40 connected with the through holes by interference fit, the base body 10 can be protected when polishing is performed under the condition that the split body 20 is separated from the base body 10.

[0053] Figure 5 is a schematic view of a retaining ring including positioning pins according to an embodiment of the present application, as shown in Figure 5 The base body 10 is provided with at least one positioning pin 11, and the first end of the split body 20 is provided with at least one pin hole 21. After the base body 10 and the split body 20 are connected, one positioning pin 11 is embedded in each pin hole 21, and different positioning pins 11 are embedded in different pin holes 21.

[0054] In addition to the connection mode of the split body 20 and the base body 10 by the bolts 30, at least one positioning pin 11 can be arranged on the base body 10, and at least one pin hole 21 is arranged on the first end of the split body 20. In the installation, the positioning pin 11 is aligned with the pin hole 21, and an external force is applied to embed the positioning pin 11 into the pin hole 21, thereby connecting the split body 20 and the base body 10.

[0055] In the embodiment of the present application, the split body 20 and the base body 10 are connected by the positioning pin 11 embedded in the pin hole 21, which can further reduce the installation and disassembly difficulty of the split body 20 and the base body 10.

[0056] Figure 6 is a schematic view of a retaining ring including first grooves according to an embodiment of the present application, and Figure 6 As shown, the second end of the base 10 is provided with first grooves 12, and the second end of the separate body 20 is provided with second grooves 22. After the first end of the separate body 20 is connected to the base 10, the first grooves 12 and the second grooves 22 are in communication. The first grooves 12 and the second grooves 22 are used to guide the polishing liquid under the polishing head during polishing of the wafer, and the polishing liquid can flow into and out from under the wafer.

[0057] During polishing of the wafer, the retaining ring 1 presses the polishing pad 3, and the liquid supply device 4 supplies the polishing liquid to the polishing pad 3 from the outside. In order to make the polishing liquid flow into the inside of the retaining ring 1 and contact the wafer, the second end of the base 10 is provided with first grooves 12, and the second end of the separate body 20 is provided with second grooves 22, and the first grooves 12 and the second grooves 22 are in communication.

[0058] Specifically, the number of the first grooves 12 is the same as the number of the second grooves 22. After the first end of the separate body 20 is connected to the base 10, each first groove 12 is in communication with one second groove 22, and the abutting interfaces of the first grooves 12 and the second grooves 22 that are in communication have the same size and shape.

[0059] By setting the number of the first grooves 12 to be the same as the number of the second grooves 22, the polishing liquid can be conveniently guided.

[0060] Specifically, the base 10 is provided with a plurality of positioning pins 11, and the first end of the separate body 20 is provided with a plurality of pin holes 21. The plurality of positioning pins 11 includes a target positioning pin, and the target positioning pin has a size and / or cross-sectional shape different from those of the other positioning pins 11. The plurality of pin holes 21 includes a target pin hole, and the target pin hole has a size and / or cross-sectional shape different from those of the other pin holes 21. When the base 10 is connected to the separate body 20, the target positioning pin is embedded in the target pin hole, so that each first groove 12 is in communication with one second groove 22 and the axes coincide.

[0061] Since the first grooves 12 need to be in communication with one second groove 22 and guide the polishing liquid, if the abutting interfaces of the first grooves 12 and the second grooves 22 are not aligned or not completely aligned when the separate body 20 and the base 10 are installed, it will have a negative impact on the effect of guiding the polishing liquid. Therefore, among the plurality of positioning pins 11 provided on the base 10, there is a target positioning pin, and correspondingly, among the plurality of pin holes 21 provided on the first end of the separate body 20, there is a target pin hole. When installing, the target positioning pin is aligned with the target pin hole, so that the abutting interfaces of the first grooves 12 and the second grooves 22 are completely aligned.

[0062] Specifically, the axes of the first grooves 12 and the second grooves 22 are straight lines, and the radii of the first grooves 12 and the second grooves 22 are the same.

[0063] By setting the axes of the first grooves 12 and the second grooves 22 as straight lines and the radii of the first grooves 12 and the second grooves 22 as the same, the polishing liquid can be better drained.

[0064] It should be noted that, Figure 6 The radii of the first grooves 12 and the second grooves 22 shown in the above are the same, but the radii of the first grooves 12 and the second grooves 22 can also be different. Specifically, the axes of the first grooves 12 and the second grooves 22 are straight lines, and along the positive direction of the axes of the first grooves 12 and the second grooves 22 after being connected, the radius of at least one of the first grooves 12 and the second grooves 22 linearly increases. Specifically, it can be as shown in Figure 7 Figure 7 The positive direction of the axes of the first grooves 12 and the second grooves 22 shown in the above points to the outside of the retaining ring 1, and the positive direction of the axes of the first grooves 12 and the second grooves 22 can also point to the inside of the retaining ring 1.

[0065] By setting the axes of the first grooves 12 and the second grooves 22 as straight lines and along the positive direction of the axes of the first grooves 12 and the second grooves 22 after being connected, the radius of at least one of the first grooves 12 and the second grooves 22 linearly increases, so that the solid particles in the polishing liquid can be left in the first grooves 12 or the second grooves 22 to avoid damaging other devices.

[0066] In the embodiments of the present application, by setting the first grooves 12 and the second grooves 22, the polishing liquid can be drained during the polishing process.

[0067] It should be noted that, Figure 6 The number of the first grooves 12 and the second grooves 22 shown in the above is the same, but in some embodiments, the number of the first grooves 12 and the second grooves 22 can be different, and the ratio of the number of the second grooves 22 to the number of the first grooves 12 can range from 1.5 to 2.5.

[0068] By setting the ratio of the number of the second grooves 22 to the number of the first grooves 12 to range from 1.5 to 2.5, the rate of the polishing liquid entering from the outside of the retaining ring 1 can be improved, and the rate of the polishing liquid flowing out from the inside of the retaining ring 1 can be reduced, thereby ensuring that there is enough polishing liquid to supply the wafer on the inside of the retaining ring 1.

[0069] Figure 8 is a schematic view of a retaining ring including a collecting groove according to an embodiment of the present application, as shown in Figure 8 ​As shown, a first concave circular-arc chamfer is arranged along the outer edge of the second end of the base 10, and a second concave circular-arc chamfer is arranged along the inner edge of the second end of the separate body 20. After the base 10 is connected with the separate body 20, the first concave circular-arc chamfer and the second concave circular-arc chamfer are spliced into the converging groove 50, and the first groove 12 and the second groove 22 are in communication with the converging groove.

[0070] Since the number of the first grooves 12 and the second grooves 22 is not the same, the first grooves 12 and the second grooves 22 cannot be connected one by one, at this time, the first concave circular-arc chamfer is arranged along the outer edge of the second end of the base 10, and the second concave circular-arc chamfer is arranged along the inner edge of the second end of the separate body 20, and after the base 10 is connected with the separate body 20, the converging groove 50 is formed through the first concave circular-arc chamfer and the second concave circular-arc chamfer, so that the drainage of the polishing liquid can be realized.

[0071] It should be noted that, similar to the above embodiment, in the case where the number of the first grooves 12 and the second grooves 22 is different, along the positive direction of the axis of the first groove 12 or the second groove 22, the radius of at least one of the first groove 12 and the second groove 22 linearly increases.

[0072] In the embodiment of the present application, the first concave circular-arc chamfer and the second concave circular-arc chamfer are spliced into the converging groove 50, so that the communication of the first grooves 12 and the second grooves 22 with different numbers can be ensured, and then the drainage of the polishing liquid can be ensured.

[0073] The second aspect of the present application provides a polishing head for CMP, which comprises the retaining ring 1 described above, and the retaining ring can adaptively change the contact area of the retaining ring and the polishing pad by arranging the separable separate body according to the need of polishing different specifications of wafers, so that the polishing effect of the wafers can be ensured.

[0074] Although the present application has been shown and described with respect to one or more implementations, equivalent alterations and modifications will occur to others skilled in the art based on the foregoing description and accompanying drawings. The present application includes all such modifications and alterations and is limited only by the scope of the following claims. In particular, with respect to the various functions performed by the above described components, the terms used to describe such components are intended to correspond, unless otherwise indicated, to any component which performs the specified function (e.g., that is functionally equivalent), even if not structurally equivalent to the disclosed structure which performs the function in the exemplary implementations illustrated by the present specification. The broadest scope of the present application is not to be determined by the contents of the summary, but rather by the contents of the following claims as interpreted according to the rules of law.

[0075] That is, the above only describes the embodiments of the present application, and does not limit the patent scope of the present application, and any equivalent structure or equivalent process transformation using the content of the present application specification and drawings, such as the mutual combination of technical features between embodiments, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the present application.

[0076] In addition, the terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined with "first", "second" can be explicitly or implicitly included one or more features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specifically limited.

[0077] In order to enable any person skilled in the art to implement and use the present application, the above description is given. In the above description, various details are listed for the purpose of explanation. It should be understood that those skilled in the art can realize the present application without using these specific details. In other embodiments, well-known processes will not be described in detail to avoid unnecessary details making the description of the present application obscure. Therefore, the present application is not intended to be limited to the embodiments shown, but is consistent with the broadest scope consistent with the principles and characteristics disclosed in the present application.

[0078] It should be noted that the various embodiments described in the present application and / or the technical features in the various embodiments can be combined with each other arbitrarily without conflict, and the technical solutions obtained after combination also fall within the protection scope of the present application.

[0079] It should be understood that the specific examples in the embodiments of the present application are only to help those skilled in the art better understand the embodiments of the present application, and not to limit the scope of the embodiments of the present application, and those skilled in the art can make various improvements and modifications on the basis of the above embodiments, and these improvements or modifications all fall within the protection scope of the present application.

[0080] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A retaining ring, applied to a polishing head, characterized in that, include: The substrate and a separable component are both annular structures. The first end of the substrate is configured to connect to a polishing head. After the first end of the component is connected to the substrate, the second end of the component and the second end of the substrate are located in the same plane, with the first end of the component located below the first end of the substrate. The second end of the component is further away from the center of the retaining ring than the second end of the substrate. The substrate and the component are used to apply pressure to the polishing pad during the polishing process where the polishing head places the wafer on the polishing pad for polishing. At least two through holes are provided on the substrate along its centerline. At least two internal threads are provided on the first end of the component along its centerline. The substrate and the split body are connected by bolts that pass through the through holes and are threaded into the internal thread holes. The substrate has at least one locating pin, and the first end of the split body has at least one pin hole. After the substrate and the split body are connected, a locating pin is embedded in each pin hole, and different locating pins are embedded in different pin holes. The second end of the substrate has a first groove, and the second end of the split body has a second groove. After the first end of the split body is connected to the substrate, the first groove and the second groove are connected. The first groove and the second groove are used to guide the polishing fluid below the polishing head during the wafer polishing process. At least a portion of the inner sidewall of the split body is a conical surface, and the angle between the inner sidewall of the conical surface and the first end of the split body and the centerline of the split body ranges from 75° to 85°. A first concave arc chamfer is provided along the outer edge of the second end of the substrate, and a second concave arc chamfer is provided along the inner edge of the second end of the split body. After the substrate and the split body are connected, the first concave arc chamfer and the second concave arc chamfer are joined together to form a confluence channel, and both the first channel and the second channel are connected to the confluence channel. The ratio of the difference between the outer radius and the inner radius of the second end of the substrate to the difference between the outer radius and the inner radius of the second end of the split body ranges from 0.5 to 2. The substrate is made of polyetheretherketone (PEEK) material, and the split body is made of polyphenylene sulfide (PPS).

2. The retaining ring according to claim 1, characterized in that, The retaining ring further includes at least two elastic plugs; the elastic plugs are used to seal the through holes when the split part separates from the base, wherein the elastic plugs are connected to the through holes by an interference fit, and different through holes are sealed by different elastic plugs.

3. The retaining ring according to claim 1, characterized in that, The number of the first grooves is the same as the number of the second grooves. After the first end of the split body is connected to the base, each first groove is connected to one second groove, and the interface between the connected first grooves and second grooves has the same size and shape.

4. The retaining ring according to claim 3, characterized in that, The base is provided with a plurality of positioning pins, and the first end of the split body is provided with a plurality of pin holes; the plurality of positioning pins includes a target positioning pin, and the target positioning pin is different in size and / or cross-sectional shape from the other positioning pins; the plurality of pin holes includes a target pin hole, and the target pin hole is different in size and / or cross-sectional shape from the other pin holes; when the base is connected to the split body, the target positioning pin is embedded in the target pin hole, so that each first groove is connected to a second groove and their axes coincide.

5. The retaining ring according to claim 3, characterized in that, The axes of the first groove and the second groove are straight lines, and the first groove and the second groove have the same radius.

6. The retaining ring according to claim 3, characterized in that, The axes of the first groove and the second groove are straight lines, and along the positive direction of the axes of the first groove and the second groove after they are connected, the radius of at least one of the first groove and the second groove increases linearly.

7. The retaining ring according to claim 1, characterized in that, The ratio of the number of the second grooves to the number of the first grooves ranges from 1.5 to 2.

5.

8. The retaining ring according to claim 1, characterized in that, The inner wall of the split body adjacent to the first end of the split body is a conical surface, and the inner wall of the split body adjacent to the second end of the split body is a cylindrical surface. The inner wall of the split body with the conical surface intersects with the inner wall of the cylindrical surface.

9. A polishing head for chemical mechanical polishing, characterized in that: Includes the retaining ring as described in any one of claims 1-8.

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