Retainer for reducing damage to grinding pad

Abstract

The utility model discloses a retainer for reducing damage of a grinding pad, which comprises a retainer body, the retainer body comprises a round disc and a grinding part, the grinding part is positioned at the bottom of the round disc, a cavity is arranged on the grinding part and is round, the cavity and the round disc are coaxially arranged, a plurality of grooves are arranged on the lower surface of the grinding part, and the grooves are communicated with the round disc. The lower surface of the grinding part makes contact with the grinding pad, the grinding part is equally divided into a plurality of grinding blocks through the grooves, the two corners of the outermost side of the groove bottom of each groove are arranged to be fillets, and the two corners of the outermost side of the opening side of each groove are arranged to be fillets. According to the protective ring capable of reducing the damage to the grinding pad, the corners of the grooves are arranged in a round corner mode, damage is small when the round corner faces make contact with the grinding pad, scratches exerted on the grinding pad by the protective ring are reduced, the extrusion area borne by the grinding pad is also reduced by reducing the design depth of the grooves, the service life of the grinding pad is prolonged, and the service life of the grinding pad is prolonged. And the frequency of replacing the grinding pad is reduced, and the production cost is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of chip processing, in particular to a retaining ring for reducing damage to a grinding pad. Background Art

[0002] In the current semiconductor chip processing field, wafers need to be ground. In this process, guard rings and grinding pads are used, and the two need to be used together. The wafer is loaded in the guard ring, and the guard ring is placed on the upper surface of the grinding pad. When working, the grinding pad will rotate on the lower surface of the guard ring. The coordinated grinding between the two becomes the key factor in the success or failure of wafer grinding.

[0003] The grinding pad is a consumable product, and the biggest problem is its service life. Usually, the grinding pad needs to be replaced after grinding about 300-400 wafers, and the time required for replacement and the matching of conditions after replacement will take up time.

[0004] The existing retainer ring causes the grinding pad to wear too quickly due to structural factors, which increases the frequency of replacement and makes the production cost high. Therefore, the wear on the grinding pad can be reduced by changing the structure of the retainer ring. Utility Model Content

[0005] The utility model aims to provide a guard ring for reducing damage to a grinding pad. By rounding the corners of a groove, the rounded surface is less damaged when in contact with the grinding pad, and the scratches caused by the guard ring on the grinding pad are significantly reduced. By reducing the designed depth of the groove, the extrusion area of ​​the grinding pad is also reduced, thereby extending the service life of the grinding pad, reducing the frequency of replacing the grinding pad, and reducing the production cost.

[0006] To achieve the above-mentioned purpose, the utility model provides a guard ring for reducing damage to a grinding pad, comprising a guard ring body, wherein the guard ring body comprises a circular disk and a grinding portion, wherein the grinding portion is located at the bottom of the circular disk, a cavity is opened on the grinding portion, and the cavity is circular, the cavity is coaxially arranged with the circular disk, a plurality of grooves are arranged on the lower surface of the grinding portion, the lower surface of the grinding portion contacts the grinding pad, the plurality of grooves equally divide the grinding portion into a plurality of grinding blocks, the two outermost corners of the groove bottom are set as chamfered corners, and the two outermost corners on the groove opening side are set as chamfered corners.

[0007] Preferably, the long sides on both sides of the groove bottom and the outermost short sides of the groove bottom are set as rounded edges, and the two long sides on the groove opening side are set as rounded edges.

[0008] Preferably, the grinding portion is circular, and the diameter of the grinding portion is smaller than the circular disk.

[0009] Preferably, the length of the groove is consistent with the width of the grinding portion after removing the cavity, and the depth of the groove is determined in proportion to the size of the retaining ring body.

[0010] Preferably, the plurality of grooves are evenly distributed on the grinding portion along the circumference of the grinding portion, the grooves are symmetrically arranged in pairs about the center line of the circular disk, and the axes of the grooves point to the center point of the circular disk.

[0011] Preferably, the circular disc is integrally provided with the grinding part.

[0012] Preferably, the outermost edge of the lower surface of the grinding block in contact with the grinding pad is set as a rounded edge.

[0013] Therefore, the utility model adopts the above-mentioned guard ring for reducing damage to the grinding pad. By rounding the corners of the groove, the rounded surface is less damaged when in contact with the grinding pad, and the scratches caused by the guard ring on the grinding pad are significantly reduced. By reducing the design depth of the groove, the extrusion area of ​​the grinding pad is also reduced, thereby extending the service life of the grinding pad, reducing the frequency of replacing the grinding pad, and reducing production costs.

[0014] The technical solution of the utility model is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the overall structure of a retaining ring for reducing damage to a grinding pad in the utility model;

[0016] Figure 2 It is a schematic diagram of the outermost short side of the bottom of a groove in a retaining ring for reducing damage to a grinding pad of the utility model;

[0017] Figure 3 It is a schematic diagram of the rounded corners and rounded edges of the groove opening side in a retaining ring for reducing the damage to the grinding pad of the utility model;

[0018] Figure 4 It is a schematic cross-sectional view of a groove in a retaining ring and a polishing pad for reducing damage to a polishing pad according to the utility model;

[0019] Figure 5 This is a front view of a groove in a retaining ring for reducing damage to a grinding pad according to the utility model;

[0020] Figure 6 The utility model is a schematic diagram of the contact between the grinding part and the grinding pad in a guard ring for reducing the damage of the grinding pad.

[0021] Reference numerals

[0022] 1. Round disc; 2. Grinding part; 3. Groove; 4. Cavity; 5. Grinding pad; 6. Chamfered corners; 7. Guard ring; 8. Grinding block; 9. Rounded edge. DETAILED DESCRIPTION

[0023] The technical solution of the utility model is further described below through the accompanying drawings and embodiments.

[0024] Unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the usual meanings understood by persons with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Words such as "include" or "comprise" and the like mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" and the like are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0025] Example

[0026] like Figure 1 As shown, a guard ring 7 for reducing damage to a grinding pad 5 comprises a guard ring 7 body, the guard ring 7 body comprises a circular disk 1 and a grinding portion 2, the grinding portion 2 is located at the bottom of the circular disk 1, the circular disk 1 and the grinding portion 2 are integrally arranged, the grinding portion 2 and the circular disk 1 are a whole, and constitute the guard ring 7. The lower surface of the grinding portion 2 is in contact with the grinding pad 5. The grinding portion 2 is circular, and the diameter of the grinding portion 2 is smaller than the circular disk 1. A cavity 4 is provided on the grinding portion 2, and the cavity 4 is circular. The cavity 4 is coaxially arranged with the circular disk 1, the grinding portion 2 is a circular ring, the wafer is located in the cavity 4 of the grinding portion 2, the guard ring 7 is located on the grinding pad 5, and the grinding pad 5 rotates on the lower surface of the guard ring 7 during operation.

[0027] A plurality of grooves 3 are provided on the lower surface of the grinding part 2, and the plurality of grooves 3 divide the grinding part 2 into a plurality of grinding blocks 8. The plurality of grooves 3 are evenly distributed on the grinding part 2 along the circumference of the grinding part 2, and the grooves 3 are symmetrically arranged in pairs about the center line of the circular disk 1, and the axis of the groove 3 points to the center point of the circular disk 1.

[0028] like Figure 3 As shown, the two outermost corners of the bottom of the groove 3 are set as chamfered corners 6, and the two outermost corners of the opening side of the groove 3 are set as chamfered corners 6. Figure 2As shown, the long sides on both sides of the bottom of the groove 3 and the outermost short sides of the bottom of the groove 3 are set as rounded edges 9, and the two long sides on the opening side of the groove 3 are set as rounded edges 9. The outermost edge of the lower surface of the grinding block 8 in contact with the grinding pad 5 is set as a rounded edge 9. In the prior art, the structure of the groove 3 of the retaining ring 7 is right-angled edges and right angles. When in contact with the grinding pad 5, these right-angled edges are too sharp, and the force is all concentrated on the right-angled corners and right-angled edges. This design defect naturally leads to stress concentration, which is not conducive to the service life of the grinding pad 5. Figure 6 As shown, the utility model replaces the right-angled edges and the right-angled structure of the groove 3 with rounded edges 9 and the rounded corner 6 structure. The rounded surface is less damaged when in contact with the grinding pad 5, and the stress is dispersed during grinding, which is beneficial to extend the service life of the grinding pad 5, thereby reducing the frequency of replacing the grinding pad 5 and reducing the production cost.

[0029] like Figure 4 and 5 As shown, the length of the groove 3 is consistent with the width of the grinding part 2 minus the cavity 4, and the depth of the groove 3 is determined in proportion to the size of the retaining ring 7 body. The depth of the groove 3 of the existing retaining ring 7 is too deep, which increases the force-bearing area of ​​the extruded grinding pad 5, all of which accelerates the damage to the grinding pad 5 and consumes the material on its surface too quickly. Compared with the prior art, the present utility model reduces the depth of the groove 3 when designing the depth of the groove 3, and the extrusion area of ​​the grinding pad 5 is also reduced, thereby reducing the surface damage to the grinding pad 5. The present utility model reduces the depth of the groove 3 of the retaining ring 7 in the prior art, and replaces the right-angled sides and right angles of the groove 3 with rounded sides 9 and chamfered corners 6, thereby reducing the extrusion area of ​​the grinding pad 5, thereby further extending its life, saving production costs, and effectively achieving the purpose of reducing costs and increasing efficiency.

[0030] Therefore, the utility model adopts the above-mentioned guard ring for reducing damage to the grinding pad. By rounding the corners of the groove, the rounded surface is less damaged when in contact with the grinding pad, and the scratches caused by the guard ring on the grinding pad are significantly reduced. By reducing the design depth of the groove, the extrusion area of ​​the grinding pad is also reduced, thereby extending the service life of the grinding pad, reducing the frequency of replacing the grinding pad, and reducing production costs.

[0031] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit it. Although the utility model has been described in detail with reference to the preferred embodiments, ordinary technicians in this field should understand that they can still modify or replace the technical solution of the utility model with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the utility model.

Claims

1. A retaining ring for reducing damage to a polishing pad, characterized in that: The invention comprises a guard ring body, which comprises a circular disk and a grinding part. The grinding part is located at the bottom of the circular disk, a cavity is opened on the grinding part, and the cavity is circular. The cavity is coaxially arranged with the circular disk, and a plurality of grooves are arranged on the lower surface of the grinding part. The lower surface of the grinding part contacts the grinding pad, and the plurality of grooves equally divide the grinding part into a plurality of grinding blocks. The two outermost corners of the groove bottom are set as chamfered corners, and the two outermost corners on the groove opening side are set as chamfered corners.

2. A retaining ring for reducing damage to a polishing pad according to claim 1, characterized in that: The long sides on both sides of the groove bottom and the outermost short sides of the groove bottom are set as rounded edges, and the two long sides on the groove opening side are set as rounded edges.

3. A retaining ring for reducing damage to a polishing pad according to claim 1, characterized in that: The grinding part is circular, and the diameter of the grinding part is smaller than the circular disk.

4. A retaining ring for reducing damage to a grinding pad according to claim 1, characterized in that: The length of the groove is consistent with the width of the grinding part after removing the cavity, and the depth of the groove is determined in proportion to the size of the retaining ring body.

5. A retaining ring for reducing damage to a polishing pad according to claim 1, characterized in that: The plurality of grooves are evenly distributed on the grinding part along the circumference of the grinding part, the grooves are symmetrically arranged in pairs about the center line of the circular disk, and the axes of the grooves point to the center point of the circular disk.

6. A retaining ring for reducing damage to a polishing pad according to claim 1, characterized in that: The circular disc is integrally arranged with the grinding part.

7. A retainer for reducing damage to a polishing pad according to claim 1, characterized in that: The outermost edge of the lower surface of the grinding block in contact with the grinding pad is set as a rounded edge.

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