Fixing ring and polishing apparatus

Abstract

The application provides a fixed ring and a polishing device. The fixed ring is arranged at one end of a polishing head close to a polishing table, and is used for holding a wafer in the fixed ring in a wafer polishing process. The fixed ring comprises a plurality of pairs of groove groups which are located on a first surface of the fixed ring close to the polishing table and penetrate the first surface from an inner ring of the fixed ring to an outer ring of the fixed ring. Each pair of groove groups comprises: a first arc-shaped groove which is curved along a first direction and is used for allowing polishing liquid to enter the fixed ring; and a second arc-shaped groove which is curved along a second direction and is used for discharging polishing by-products out of the fixed ring, and the second direction is opposite to the first direction or forms an included angle with the first direction. The above technical scheme sets the arc-shaped grooves, so that the groove direction is more suitable for the flow path of the polishing liquid entering the fixed ring and the polishing liquid by-products discharging out of the fixed ring, reduces the accumulation of the liquid in the groove, improves the wafer polishing environment and further improves the wafer polishing quality.

Description

Technical Field

[0001] This invention relates to the field of semiconductors, and more particularly to a fixing ring and a grinding apparatus. Background Technology

[0002] As semiconductor device dimensions shrink, excessive surface irregularities on the wafer surface caused by multilayer interconnects or deposition processes with large fill depths make it difficult to focus during photolithography, reducing the ability to control linewidth and decreasing the uniformity of linewidth across the entire wafer. Therefore, the industry introduced chemical mechanical polishing (CMP) to planarize the wafer surface. With the advancement of semiconductor fabrication into the sub-micron stage, CMP has become an indispensable manufacturing technology. Within the CMP process, the CMP apparatus has become one of the most important pieces of equipment in semiconductor manufacturing.

[0003] Chemical mechanical polishing (CMP) is a process that uses chemical etching and mechanical force to planarize silicon wafers or other substrate materials during manufacturing. In modern semiconductor manufacturing CMP processes, a retaining ring on the polishing head is used to hold the wafer within the ring during the semiconductor wafer polishing process so that one side of the wafer can be polished.

[0004] Please see Figures 1-2 ,in, Figure 1 This is a schematic diagram of one embodiment of a chemical mechanical grinding machine. Figure 2 This is a schematic diagram of one embodiment of the retaining ring. Figure 1 As shown, the chemical mechanical polishing (CMP) machine includes a polishing head 11 and a polishing table 12. The polishing head 11 is equipped with a retaining ring 13 for holding the wafer 19 within the ring during the semiconductor wafer polishing process to polish one side of the wafer 19; the arrows indicate the rotation direction of the corresponding components. Figure 2 As shown, the fixing ring 13 is provided with a fixed number and size of grooves 21, which allow a certain amount of polishing fluid to enter the wafer 19 fixed inside the ring (see reference). Figure 1 The surface (as shown) is ground, and then the grinding fluid by-products are discharged through the groove 21 after grinding. However, the by-products generated after grinding will accumulate in the groove 21, and the residue in the groove 21 will increase as the grinding table 12 continues to grind.

[0005] Therefore, reducing the accumulation of polishing slurry byproducts and improving the wafer polishing environment to enhance wafer polishing quality are problems that need to be addressed. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to reduce the accumulation of by-products in the polishing slurry, improve the wafer polishing environment, and thus improve the quality of wafer polishing, and to provide a fixing ring and polishing equipment.

[0007] To address the aforementioned problems, the present invention provides a retaining ring disposed at one end of the grinding head near the grinding table, for holding the wafer within the retaining ring during the wafer grinding process; comprising multiple pairs of grooves located on a first surface of the retaining ring near the grinding table, extending from the inner ring of the retaining ring to the outer ring of the retaining ring through the first surface, each pair of grooves comprising: a first arc-shaped groove, the first arc-shaped groove being curved along a first direction for allowing grinding slurry to enter the retaining ring; and a second arc-shaped groove, the second arc-shaped groove being curved along a second direction for discharging grinding byproducts from the retaining ring, wherein the second direction is opposite to or forms an angle with the first direction.

[0008] In some embodiments, the first direction is the rotation direction of the grinding head.

[0009] In some embodiments, the corresponding ends of the first arcuate groove and the second arcuate groove are far apart from each other.

[0010] In some embodiments, the fixing ring includes 8 to 10 pairs of the groove groups; the distance between two adjacent groove groups is 55 mm to 66 mm; the groove width of the first arc-shaped groove and the second arc-shaped groove is 3 mm to 4 mm; the center distance between the first arc-shaped groove and the second arc-shaped groove in the same groove group is 3 mm to 4.5 mm.

[0011] In some embodiments, the corresponding ends of the first arcuate groove and the second arcuate groove are close to each other.

[0012] In some embodiments, the fixing ring includes 8 to 10 pairs of the groove groups; the distance between two adjacent groove groups is 50 mm to 60 mm; the groove width of the first arc-shaped groove and the second arc-shaped groove is 3 mm to 4 mm; the center distance between the first arc-shaped groove and the second arc-shaped groove in the same groove group is 4.5 mm to 5.5 mm.

[0013] In some embodiments, the first arcuate groove has a first end near the inner ring of the fixing ring and a second end near the outer ring of the fixing ring; the second arcuate groove has a first end near the inner ring of the fixing ring and a second end near the outer ring of the fixing ring, and there is a first distance between the first end of the first arcuate groove and the first end of the second arcuate groove; there is a second distance between the second end of the first arcuate groove and the second end of the second arcuate groove; wherein the first distance is less than the second distance.

[0014] In some embodiments, the opening width at the first end of the first arcuate groove is smaller than the opening width at its second end; the opening width at the first end of the second arcuate groove is smaller than the opening width at its second end.

[0015] In some embodiments, the fixing ring includes 6 to 10 pairs of the groove groups; the spacing between two adjacent groove groups is 55 mm to 65 mm; the width of the first end of the first arc-shaped groove is 2.5 mm to 3.5 mm, and the width of its second end is 3.5 mm to 4.5 mm; the width of the first end of the second arc-shaped groove is 3.5 mm to 4 mm, and the width of its second end is 4 mm to 5 mm; the center distance between the first arc-shaped groove and the second arc-shaped groove in the same groove group is 5 mm to 6 mm.

[0016] In some embodiments, the first arcuate groove and the second arcuate groove form an intersecting structure on the first surface.

[0017] In some embodiments, the fixing ring includes 8 to 12 pairs of groove groups; the spacing between two adjacent groove groups is 55 mm to 65 mm; the width of the first end of the first arc-shaped groove is 3 mm to 3.5 mm, and the width of the second end is 3.5 mm to 4.5 mm; the width of the first end of the second arc-shaped groove is 3.8 mm to 4.5 mm, and the width of the second end is 4 mm to 5 mm; the center distance between the first arc-shaped groove and the second arc-shaped groove in the same groove group is 5 mm to 6 mm.

[0018] To address the aforementioned problems, the present invention provides a grinding apparatus, including a grinding head and a grinding table; it further includes a retaining ring disposed at one end of the grinding head near the grinding table, for holding the wafer within the retaining ring during the wafer grinding process, wherein the retaining ring is the retaining ring described in the present invention.

[0019] The above technical solution, by setting arc-shaped grooves, makes the groove direction more suitable for the flow path of the polishing slurry entering the fixing ring and the polishing slurry by-products exiting the fixing ring, reducing liquid flow resistance and liquid accumulation in the grooves, improving the wafer polishing environment and thus improving wafer polishing quality. By setting the first arc-shaped groove in the same direction as the rotation direction of the polishing head, it conforms to the polishing slurry inflow trajectory, making the polishing slurry enter the ring more smoothly and reducing polishing slurry crystallization. The second arc-shaped groove, set in the opposite direction to the first arc-shaped groove, conforms to the polishing slurry by-product outflow trajectory, allowing polishing slurry by-products to flow out of the fixing ring as much as possible, reducing residue in the second arc-shaped groove. Furthermore, setting different grooves for polishing slurry inflow and polishing slurry by-product outflow reduces the cross-contamination of the two liquids, reduces contamination of the polishing slurry by polishing slurry by-products, and reduces mutual obstruction between the two liquids during inflow and outflow. Setting grooves that are wider at the outer edge and narrower at the inner edge allows for smooth polishing slurry inflow, and also allows polishing slurry by-products to be thrown outwards under centrifugal force, reducing by-products deposited in the grooves.

[0020] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the invention. Techniques, methods, and apparatus known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and apparatus should be considered part of the specification. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of one embodiment of a chemical mechanical grinding machine.

[0023] Figure 2 This is a schematic diagram of one embodiment of a fixing ring.

[0024] Figure 3 This is a schematic diagram of the structure of the first embodiment of the fixing ring described in this invention.

[0025] Figure 4 for Figure 3 An enlarged schematic diagram of the trench assembly in the illustrated embodiment.

[0026] Figure 5A This is a schematic diagram of the second embodiment of the fixing ring described in this invention.

[0027] Figure 5B for Figure 5AAn enlarged schematic diagram of the trench assembly in the illustrated embodiment.

[0028] Figure 6A This is a structural schematic diagram of the third embodiment of the fixing ring described in this invention.

[0029] Figure 6B for Figure 6A An enlarged schematic diagram of the trench assembly in the illustrated embodiment.

[0030] Figure 7A This is a structural schematic diagram of the fourth embodiment of the fixing ring described in this invention.

[0031] Figure 7B for Figure 7A An enlarged schematic diagram of the trench assembly in the illustrated embodiment.

[0032] Figure 8 This is a schematic diagram of an embodiment of the grinding equipment described in this invention. Detailed Implementation

[0033] The technical solutions in the embodiments of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] To improve the structure of the grinding machine dresser and prevent humectant from splashing onto the grinding pad to stabilize wafer grinding quality, this invention provides a retaining ring disposed at one end of the grinding head near the grinding table, used to hold the wafer within the retaining ring during the wafer grinding process. The retaining ring includes multiple pairs of grooves located on a first surface near the grinding table, extending from the inner ring to the outer ring of the retaining ring through the first surface. Each pair of grooves includes: a first arc-shaped groove, curved along a first direction to allow grinding fluid to enter the retaining ring; and a second arc-shaped groove, curved along a second direction to discharge grinding byproducts from the retaining ring, wherein the second direction is opposite to or forms an angle with the first direction.

[0035] The above technical solution, by setting arc-shaped grooves, makes the groove direction more suitable for the flow path of the polishing slurry entering the fixing ring and the polishing slurry by-products exiting the fixing ring, reduces liquid flow obstruction and liquid accumulation in the grooves, improves the wafer polishing environment and thus improves the wafer polishing quality.

[0036] Please refer to the following: Figures 3-4 ,in, Figure 3 This is a schematic diagram of the structure of the first embodiment of the fixing ring described in this invention. Figure 4 for Figure 3 An enlarged schematic diagram of the trench assembly in the illustrated embodiment.

[0037] like Figure 3 As shown, each of the groove groups 30 includes a first arcuate groove 31 and a second arcuate groove 32 located on a first surface 301 of the fixed ring near the grinding table, extending from the inner ring of the fixed ring to the outer ring of the fixed ring through the first surface 301. The first arcuate groove 31 is curved along a first direction D1 to allow grinding fluid to enter the fixed ring. In some embodiments, the first direction D1 is the rotation direction of the grinding head. In this embodiment, the first direction D1 is counterclockwise. The second arcuate groove 32 is curved along a second direction D2 to discharge grinding byproducts from the fixed ring, and the second direction D2 is opposite to or forms an angle with the first direction D1. In this embodiment, the second direction D2 is opposite to the first direction D1 and is clockwise.

[0038] In this embodiment, the corresponding ends of the first arc-shaped groove 31 and the second arc-shaped groove 32 are far apart from each other, that is, the first arc-shaped groove 31 and the second arc-shaped groove 32 are arranged opposite to each other. Specifically, the first arc-shaped groove 31 has a first end near the inner ring of the fixing ring and a second end near the outer ring of the fixing ring, and the second arc-shaped groove 32 also has a first end near the inner ring of the fixing ring and a second end near the outer ring of the fixing ring. The first end of the first arc-shaped groove 31 and the first end of the second arc-shaped groove 32 are far apart from each other, and the second end of the first arc-shaped groove 31 and the second end of the second arc-shaped groove 32 are far apart from each other.

[0039] In this embodiment, the retaining ring better categorizes the functions of grinding slurry entry and by-product removal, ensuring they do not interfere with each other. That is, the arc-shaped grooves increase both the smoothness of grinding slurry inflow and the smoothness of by-product removal, reducing by-product accumulation. Furthermore, each groove group 30 can have three or more arc-shaped grooves to adapt to more complex grinding environments.

[0040] In this embodiment, the fixing ring includes 10 pairs of groove groups 30; the distance S30 between two adjacent groove groups 30 is 55mm to 66mm. In other embodiments, the fixing ring may also include 8 or 9 pairs of groove groups 30; the number of groove groups 30 may be increased or decreased, or the distance S30 between two adjacent groove groups 30 may be adjusted, as needed.

[0041] like Figure 4As shown, in this embodiment, the opening width W311 of the first end of the first arc-shaped groove 31 can be the same as the opening width W312 of its second end, and equal to the opening width W321 of the first end and the opening width W322 of the second arc-shaped groove 32. The opening widths W311 and W312 of the first and second ends of the first and second arc-shaped grooves 31, and the opening widths W321 and W322 of the second arc-shaped groove 32, are all 3mm to 4mm. In other embodiments, the opening width W311 of the first end of the first arc-shaped groove 31 can be smaller than the opening width W312 of its second end, and the opening width W321 of the first end of the second arc-shaped groove 32 can also be smaller than the opening width W322 of its second end. Setting a groove that is wider at the outside and narrower at the inside allows for smooth flow of the polishing slurry, and also allows polishing slurry byproducts to be thrown outwards under centrifugal force, reducing the byproducts deposited in the groove.

[0042] In this embodiment, the center distance S31 between the first arc-shaped groove 31 and the second arc-shaped groove 32 within the same groove group 30 is 3mm to 4.5mm. In other embodiments, the radius of curvature of the arc-shaped groove or the corresponding end distance of the arc-shaped groove can be adjusted as needed to adjust the center distance S31 between the first arc-shaped groove 31 and the second arc-shaped groove 32 within the same groove group 30.

[0043] Please refer to the following: Figures 5A-5B ,in, Figure 5A This is a schematic diagram of the second embodiment of the fixing ring described in this invention. Figure 5B for Figure 5A An enlarged schematic diagram of the trench assembly in the illustrated embodiment.

[0044] like Figure 5A As shown, the groove assembly 50 includes a first arc-shaped groove 51 and a second arc-shaped groove 52 located on a first surface 501 near the grinding table of the fixed ring, extending from the inner ring of the fixed ring to the outer ring of the fixed ring through the first surface 501. Figure 3 The difference in the illustrated embodiment is that, in this embodiment, the corresponding ends of the first arc-shaped groove 51 and the second arc-shaped groove 52 are close to each other, that is, the first arc-shaped groove 51 and the second arc-shaped groove 52 are arranged opposite each other. The first arc-shaped groove 51 has a first end close to the inner ring of the fixing ring and a second end close to the outer ring of the fixing ring, and the second arc-shaped groove 52 also has a first end close to the inner ring of the fixing ring and a second end close to the outer ring of the fixing ring. The first end of the first arc-shaped groove 51 and the first end of the second arc-shaped groove 52 are close to each other, and the second end of the first arc-shaped groove 51 and the second end of the second arc-shaped groove 52 are close to each other.

[0045] In this embodiment, the fixing ring includes 10 pairs of groove groups 50; the distance S50 between two adjacent groove groups 50 is 50mm to 60mm. In other embodiments, the fixing ring may also include 8 or 9 pairs of groove groups 50; the number of groove groups 50 may be increased or decreased, or the distance S50 between two adjacent groove groups 50 may be adjusted, as needed.

[0046] like Figure 5B As shown, in this embodiment, the opening width W511 of the first end of the first arc-shaped groove 51 can be the same as the opening width W512 of its second end, and equal to the opening width W521 of the first end and the opening width W522 of the second arc-shaped groove 52. The opening widths W511 and W512 of the first and second ends of the first and second arc-shaped grooves 51, and the opening widths W521 and W522 of the second arc-shaped groove 52, are all 3mm to 4mm. In other embodiments, the opening width W511 of the first end of the first arc-shaped groove 51 can be smaller than the opening width W512 of its second end, and the opening width W521 of the first end of the second arc-shaped groove 52 can also be smaller than the opening width W522 of its second end. Setting a groove that is wider at the outside and narrower at the inside allows for smooth flow of the polishing slurry, and also allows polishing slurry byproducts to be thrown outwards under centrifugal force, reducing the byproducts deposited in the groove.

[0047] In this embodiment, the center distance S51 between the first arc-shaped groove 51 and the second arc-shaped groove 52 within the same groove group 50 is 4.5mm to 5.5mm. In other embodiments, the radius of curvature of the arc-shaped groove or the corresponding end distance of the arc-shaped groove can be adjusted as needed to adjust the center distance S51 between the first arc-shaped groove 51 and the second arc-shaped groove 52 within the same groove group 50.

[0048] Please refer to the following: Figures 6A-6B ,in, Figure 6A This is a structural schematic diagram of the third embodiment of the fixing ring described in this invention. Figure 6B for Figure 6A An enlarged schematic diagram of the trench assembly in the illustrated embodiment.

[0049] like Figure 6AAs shown, the groove assembly 60 includes a first arc-shaped groove 61 and a second arc-shaped groove 62 located on a first surface 601 near the grinding table of the fixed ring, extending from the inner ring of the fixed ring to the outer ring of the fixed ring through the first surface 601. The first arc-shaped groove 61 has a first end near the inner ring of the fixed ring and a second end near the outer ring of the fixed ring, and the second arc-shaped groove 62 has a first end near the inner ring of the fixed ring and a second end near the outer ring of the fixed ring; the first distance between the first end of the first arc-shaped groove 61 and the first end of the second arc-shaped groove 62 is less than the second distance between the second end of the first arc-shaped groove 61 and the second end of the second arc-shaped groove 62. That is, the first arc-shaped groove 61 and the second arc-shaped groove 62 have a bifurcated structure.

[0050] In this embodiment, the fixing ring includes 10 pairs of groove groups 60; the distance S60 between two adjacent groove groups 60 is 55mm to 65mm. In other embodiments, the fixing ring may also include 6, 7, 8, or 9 pairs of groove groups 60; the number of groove groups 60 may be increased or decreased, or the distance S60 between two adjacent groove groups 60 may be adjusted, as needed.

[0051] like Figure 6B As shown, in this embodiment, there is a first distance S601 between the first end of the first arc-shaped groove 61 and the first end of the second arc-shaped groove 62; there is a second distance S601 between the second end of the first arc-shaped groove 61 and the second end of the second arc-shaped groove 62; wherein, the first distance S601 is less than the second distance S602.

[0052] In this embodiment, the opening width W611 at the first end of the first arc-shaped groove 61 is smaller than the opening width W612 at its second end; the opening width W621 at the first end of the second arc-shaped groove 62 is smaller than the opening width W622 at its second end. The opening width W611 at the first end of the first arc-shaped groove 61 is 2.5mm to 3.5mm, and the opening width W612 at its second end is 3.5mm to 4.5mm; the opening width W621 at the first end of the second arc-shaped groove 62 is 3.5mm to 4mm, and the opening width W622 at its second end is 4mm to 5mm. The grooves, wider at the outside and narrower at the inside, allow for smooth flow of the polishing slurry and also allow polishing slurry byproducts to be thrown outwards under centrifugal force, reducing the amount of byproducts deposited in the grooves.

[0053] In this embodiment, the center distance S61 between the first arc-shaped groove 61 and the second arc-shaped groove 62 within the same groove group 60 is 5mm to 6mm. In other embodiments, the radius of curvature of the arc-shaped groove or the corresponding end distance of the arc-shaped groove can be adjusted as needed to adjust the center distance S61 between the first arc-shaped groove 61 and the second arc-shaped groove 62 within the same groove group 60.

[0054] Please refer to the following: Figures 7A-7B ,in, Figure 7A This is a structural schematic diagram of the fourth embodiment of the fixing ring described in this invention. Figure 7B for Figure 7A An enlarged schematic diagram of the trench assembly in the illustrated embodiment.

[0055] like Figure 7A As shown, the groove assembly 70 includes a first arc-shaped groove 71 and a second arc-shaped groove 72 located on a first surface 701 near the grinding table of the fixed ring, and extending from the inner ring of the fixed ring to the outer ring of the fixed ring through the first surface 701. Figure 3 The difference in the illustrated embodiment lies in that, in this embodiment, the first arc-shaped groove 71 and the second arc-shaped groove 72 form an intersecting structure on the first surface 701 of the fixing ring. Setting the first arc-shaped groove 71 and the second arc-shaped groove 72 as an intersecting structure allows the grooves into which the grinding slurry enters to be more inclined. Furthermore, the staggered effect ensures that after entering the grooves, the grinding slurry can split into two paths and enter the retaining ring; similarly, byproducts also split into two paths when they reach the middle of the grooves. Overall, this increases the efficiency of grinding slurry entry and exit, effectively improving the grinding rate and product yield.

[0056] In this embodiment, the fixing ring includes 10 pairs of groove groups 70; the spacing S70 between two adjacent groove groups 70 is 55mm to 65mm. In other embodiments, the fixing ring may also include 8, 9, 11, or 12 pairs of groove groups 70; the number of groove groups 70 may be increased or decreased, or the spacing S70 between two adjacent groove groups 70 may be adjusted, as needed.

[0057] like Figure 7BAs shown, in this embodiment, the first arc-shaped groove 71 has a first end near the inner ring of the fixing ring and a second end near the outer ring of the fixing ring, and the opening width W711 of the first end of the first arc-shaped groove 71 is smaller than the opening width W712 of its second end; the second arc-shaped groove 72 has a first end near the inner ring of the fixing ring and a second end near the outer ring of the fixing ring, and the opening width W721 of the first end of the second arc-shaped groove 72 is smaller than the opening width W722 of its second end. The opening width W711 of the first end of the first arc-shaped groove 71 is 3.5mm to 4.5mm, and the opening width W712 of its second end is 3.5mm to 4.5mm; the opening width W721 of the first end of the second arc-shaped groove 72 is 3.8mm to 4.5mm, and the opening width W722 of its second end is 4mm to 5mm. Setting up grooves that are wider on the outside and narrower on the inside allows the grinding slurry to flow in smoothly, while also allowing grinding slurry byproducts to be thrown outwards under centrifugal force, reducing the amount of byproducts deposited in the grooves.

[0058] In this embodiment, the center distance S71 between the first arc-shaped groove 71 and the second arc-shaped groove 72 within the same groove group 70 is 5mm to 6mm. In other embodiments, the radius of curvature of the arc-shaped groove or the corresponding end distance of the arc-shaped groove can be adjusted as needed to adjust the center distance S71 between the first arc-shaped groove 71 and the second arc-shaped groove 72 within the same groove group 70.

[0059] Based on the same inventive concept, the present invention also provides a grinding device.

[0060] Please see Figure 8 This is a schematic diagram of an embodiment of the grinding equipment described in this invention. Figure 8 As shown, the grinding equipment includes a grinding head 80 and a grinding table 81. The grinding head 80 rotates along a first direction D1. In this embodiment, the first direction D1 is counterclockwise. The grinding head 80 also includes a retaining ring 82, disposed at one end of the grinding head 80 near the grinding table 81, for holding the wafer within the retaining ring 82 during the wafer grinding process. The retaining ring 82 includes multiple pairs of grooves located on a first surface 821 near the grinding table, extending from the inner ring of the retaining ring 82 to the outer ring of the retaining ring 82 through the first surface 821. Specifically, the arrangement of the retaining ring 82 and the corresponding groove groups is as follows: Figures 3 to 7B As shown, it will not be elaborated further here.

[0061] The above technical solution, by setting arc-shaped grooves on the fixed ring, makes the groove direction more suitable for the flow path of the polishing slurry entering the fixed ring and the discharge of polishing slurry by-products from the fixed ring, reducing liquid flow resistance and liquid accumulation in the grooves, improving the wafer polishing environment and thus improving wafer polishing quality. By setting the first arc-shaped groove in the same direction as the rotation direction of the polishing head, it conforms to the polishing slurry inflow trajectory, making the polishing slurry enter the ring more smoothly and reducing polishing slurry crystallization. The second arc-shaped groove, set in the opposite direction to the first arc-shaped groove, conforms to the polishing slurry by-product outflow trajectory, allowing polishing slurry by-products to flow out of the fixed ring as much as possible, reducing residue in the second arc-shaped groove. Furthermore, setting different grooves for polishing slurry inflow and polishing slurry by-product outflow reduces the cross-contamination of the two liquids, reduces contamination of the polishing slurry by polishing slurry by-products, and reduces mutual obstruction between the two liquids during inflow and outflow. Setting grooves that are wider at the outer edge and narrower at the inner edge allows for smooth polishing slurry inflow, and also allows polishing slurry by-products to be thrown outwards under centrifugal force, reducing by-products deposited in the grooves.

[0062] It should be noted that references to "an embodiment," "an embodiment," "an exemplary embodiment," "some embodiments," etc., in the specification indicate that the described embodiments may include specific features, structures, or characteristics, but each embodiment may not necessarily include that specific feature, structure, or characteristic. Furthermore, such phrases do not necessarily refer to the same embodiment. In addition, when a specific feature, structure, or characteristic is described in connection with an embodiment, whether explicitly described or not, implementing such a feature, structure, or characteristic in conjunction with other embodiments is within the knowledge of those skilled in the art.

[0063] Generally, terms can be understood at least partially from their usage in context. For example, the term "one or more," as used herein, depends at least partially on the context and can be used to describe any feature, structure, or characteristic in a singular sense, or in a plural sense, to describe a combination of features, structures, or characteristics. Similarly, terms such as "a," "a," or "the" can also be understood, at least partially on the context, to express either a singular or plural usage. Furthermore, the term "based on" can be understood not necessarily to express an exclusive set of factors, but rather, alternatively, also at least partially on the context, to allow for the presence of other factors that are not necessarily explicitly described. It should also be noted in this specification that "connection / coupling" refers not only to a direct coupling of one component to another, but also to an indirect coupling of one component to another via an intermediate component.

[0064] It should be noted that the terms "comprising" and "having," and their variations, used in this invention document are intended to cover non-exclusive inclusion. The terms "first," "second," etc., are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence, unless explicitly indicated by the context. It should be understood that such data used in this way can be interchanged where appropriate. Furthermore, embodiments and features in the embodiments of this invention can be combined with each other unless otherwise specified. In addition, descriptions of well-known components and technologies have been omitted in the above description to avoid unnecessarily obscuring the concepts of this invention. In the various embodiments described above, each embodiment focuses on its differences from other embodiments; similar or identical parts between embodiments can be referred to interchangeably.

[0065] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A retaining ring, disposed at one end of a grinding head near a grinding table, for holding a wafer within the retaining ring during a wafer grinding process; characterized in that, This includes multiple pairs of groove groups located on the first surface of the fixed ring near the grinding table, extending from the inner ring of the fixed ring to the outer ring of the fixed ring through the first surface, each pair of groove groups including: The first arc-shaped groove bends counterclockwise from the outer ring of the fixed ring to the inner ring of the fixed ring, so as to allow the grinding fluid to enter the fixed ring. The second arc-shaped groove bends clockwise from the outer ring of the fixed ring to the inner ring of the fixed ring, and is used to discharge grinding byproducts from the fixed ring. The opening width at the first end of the first arc-shaped groove is the same as the opening width at its second end, and is equal to the opening width at the first end of the second arc-shaped groove and the opening width at its second end. The counterclockwise direction is the rotation direction of the grinding head.

2. The fixing ring according to claim 1, characterized in that, The corresponding ends of the first arc-shaped groove and the second arc-shaped groove are far apart from each other.

3. The fixing ring according to claim 2, characterized in that, The fixing ring comprises 8 to 10 pairs of the groove groups; The distance between two adjacent trench groups is 55mm~66mm; The width of the first arc-shaped groove and the second arc-shaped groove is 3mm~4mm; The center distance between the first arc-shaped groove and the second arc-shaped groove in the same groove group is 3mm to 4.5mm.

4. The fixing ring according to claim 1, characterized in that, The corresponding ends of the first arc-shaped groove and the second arc-shaped groove are close to each other.

5. The fixing ring according to claim 4, characterized in that, The fixing ring comprises 8 to 10 pairs of the groove groups; The distance between two adjacent trench groups is 50mm~60mm; The width of the first arc-shaped groove and the second arc-shaped groove is 3mm~4mm; The center distance between the first arc-shaped groove and the second arc-shaped groove in the same groove group is 4.5mm~5.5mm.

6. A grinding apparatus, comprising a grinding head and a grinding table; characterized in that, Also includes: A retaining ring is disposed at one end of the grinding head near the grinding table for holding the wafer within the retaining ring during the wafer grinding process, wherein the retaining ring is the retaining ring according to any one of claims 1 to 5.

Images