CN-122003312-A - Chemical Mechanical Polishing (CMP) process without retaining ring

Abstract

An exemplary carrier head for a chemical mechanical polishing apparatus may include a carrier body. The carrier head may include a flexible membrane coupled with the carrier body. The flexible membrane may include a substrate receiving surface facing away from the carrier body. The substrate receiving surface may include a plurality of gripping elements protruding away from the substrate receiving surface. The maximum lateral dimension of each of the plurality of gripping elements may be no greater than 2 millimeters.

Inventors

• ZHANG ZHENWEI
• P. Depp
• J.ZHANG
• Sekine healthy people
• TANG JIANSHE
• WU HAOCHENG

Assignees

• 应用材料公司

Dates

Publication Date

20260508

Application Date

20241003

Priority Date

20231010

Claims (20)

1. 1. A carrier head for a chemical mechanical polishing apparatus, the carrier head comprising: a carrier body; A flexible membrane coupled with the carrier body, the flexible membrane comprising a substrate receiving surface facing away from the carrier body, wherein: The substrate receiving surface includes a plurality of gripping elements protruding away from the substrate receiving surface, an The maximum lateral dimension of each of the plurality of gripping elements is no greater than 2 millimeters.
2. 2. The carrier head of a chemical mechanical polishing apparatus as recited in claim 1, wherein: each gripping element of the plurality of gripping elements includes a wide base that tapers toward the gripping surface.
3. 3. The carrier head of a chemical mechanical polishing apparatus as recited in claim 2, wherein: The gripping surface is convex.
4. 4. The carrier head of a chemical mechanical polishing apparatus as recited in claim 2, wherein: The gripping surface is concave.
5. 5. The carrier head of a chemical mechanical polishing apparatus as recited in claim 1, wherein: Each gripping element of the plurality of gripping elements is substantially mushroom-shaped.
6. 6. The carrier head of a chemical mechanical polishing apparatus of claim 1, the carrier head further comprising: a plurality of substrate holding members coupled with the carrier body, wherein each of the plurality of substrate holding members is disposed at a different angular position around a periphery of the substrate receiving surface.
7. 7. The carrier head of a chemical mechanical polishing apparatus as recited in claim 6, wherein: the plurality of retaining members collectively extend along less than about 20% of the periphery of the substrate receiving surface.
8. 8. The carrier head of a chemical mechanical polishing apparatus of claim 1, the carrier head further comprising: an adhesive applied to the gripping surface of at least some of the plurality of gripping elements.
9. 9. The carrier head of a chemical mechanical polishing apparatus as recited in claim 1, wherein: The maximum lateral dimension of each of the plurality of gripping elements is no greater than 0.1 millimeters.
10. 10. The carrier head of a chemical mechanical polishing apparatus as recited in claim 1, wherein: Each of the plurality of gripping elements is flexible in a lateral direction.
11. 11. A flexible membrane for a chemical mechanical polishing apparatus, the flexible membrane comprising: a flexible diaphragm body having a substrate receiving surface, wherein: The substrate receiving surface includes a plurality of gripping elements protruding away from the substrate receiving surface, an The maximum lateral dimension of each of the plurality of gripping elements is no greater than 2 millimeters.
12. 12. The flexible membrane for a chemical mechanical polishing apparatus as recited in claim 11, wherein: each gripping element of the plurality of gripping elements includes a wide base that tapers toward the gripping surface.
13. 13. The flexible membrane for a chemical mechanical polishing apparatus as recited in claim 12, wherein: The gripping surface is convex.
14. 14. The flexible membrane for a chemical mechanical polishing apparatus as recited in claim 12, wherein: The gripping surface is concave.
15. 15. The flexible membrane for a chemical mechanical polishing apparatus as recited in claim 11, wherein: The height of each gripping element of the plurality of gripping elements is no greater than 1 millimeter.
16. 16. The flexible membrane for a chemical mechanical polishing apparatus as recited in claim 11, wherein: The substrate receiving surface has an open area of less than 50%.
17. 17. A method of polishing a substrate, the method comprising: bonding a plurality of gripping elements of a substrate receiving surface of a flexible membrane of a carrier head to a substrate; Flowing polishing slurry from a slurry source to a polishing pad, and And moving the bearing head to polish the substrate on the top end of the polishing pad.
18. 18. The method of polishing a substrate according to claim 17, wherein: moving the carrier head includes one or both of rotating the carrier head and translating the carrier head laterally relative to the polishing pad.
19. 19. The method of polishing a substrate according to claim 17, wherein: the carrier head includes a plurality of substrate holding members disposed at different angular positions about a periphery of the substrate receiving surface.
20. 20. The method of polishing a substrate according to claim 17, wherein: each substrate holding member of the plurality of substrate holding members includes an inner portion that contacts a periphery of the substrate and terminates before reaching the polishing pad and an outer region that contacts the polishing pad.

Description

Chemical Mechanical Polishing (CMP) process without retaining ring Technical Field The benefit and priority of U.S. patent application Ser. No. 18/483,973, entitled "RETAINING-RING-LESS CMP PROCESS," filed on 10 months 2023, is hereby incorporated by reference in its entirety. The present technology relates to semiconductor systems, processes, and devices. More particularly, the present technology relates to polishing films deposited on a substrate. Background Integrated circuits are typically formed on a substrate by sequentially depositing conductive, semiconductive and/or insulative layers on a silicon wafer. Various fabrication processes planarize layers above the substrate between processing steps. For example, in some applications, such as polishing a metal layer to form vias, plugs, and/or lines in trenches of a patterned layer, the upper cladding layer may be planarized until the top surface of the patterned layer is exposed. In other applications, such as planarization of dielectric layers for lithography, the upper cladding layer is polished until a desired thickness is maintained on the lower layer. Chemical Mechanical Polishing (CMP) is a common planarization method. Such planarization methods typically require the substrate to be mounted on a carrier or polishing head. The exposed surface of the substrate is typically placed on a rotating polishing pad. The carrier head provides a controlled load on the substrate pushing it toward the polishing pad. An abrasive polishing slurry is typically provided to the surface of the polishing pad. One problem with CMP is that the entire surface of the substrate is uniformly polished. Typically, the polishing rate may be higher or lower in the region of the polishing pad near the edge of the substrate, particularly near the leading and/or trailing edges of the substrate, due to the design of the CMP system. For example, when the substrate and polishing pad are moved relative to each other, the trailing edge of the substrate may contact the inner retaining ring, which may create a side load on the substrate. Side loads may be concentrated at the contact point of the trailing edge, which may result in a higher polishing rate at the trailing edge. Thus, the film thickness may be non-uniform at one or more edge regions of the substrate. Such film non-uniformity may cause lithographic problems and may lead to reduced die yield for a given substrate. Accordingly, there is a need for improved systems and methods that can be used to polish a substrate in order to produce a uniform film over the entire surface area of the substrate. The present technology meets these and other needs. Disclosure of Invention An exemplary carrier head for a chemical mechanical polishing apparatus may include a carrier body. The carrier head may include a flexible membrane coupled to the carrier body. The flexible membrane may include a substrate receiving surface facing away from the carrier body. The substrate receiving surface may include a plurality of gripping elements protruding away from the substrate receiving surface. The maximum lateral dimension of each of the plurality of gripping elements may be no greater than 2 millimeters. In some embodiments, each of the plurality of gripping elements may include a wide base that tapers toward the gripping surface. The gripping surface may be convex. The gripping surface may be concave. Each of the plurality of gripping elements may be generally mushroom-shaped. The carrier head may include a plurality of substrate holding members coupled with the carrier body. Each of the plurality of substrate holding members may be disposed at a different angular position around the periphery of the substrate receiving surface. The plurality of retaining members may collectively extend along less than about 20% of the periphery of the substrate receiving surface. The adhesive may be applied to the gripping surface of at least some of the plurality of gripping elements. Each of the plurality of gripping elements may have a maximum lateral dimension of no more than 0.1 millimeters. Each of the plurality of gripping elements may have flexibility in the lateral direction. Some embodiments of the present technology may include a flexible membrane for use in a chemical mechanical polishing apparatus. The flexible membrane may include a flexible membrane body having a substrate receiving surface. The substrate receiving surface may include a plurality of gripping elements protruding away from the substrate receiving surface. The maximum lateral dimension of each of the plurality of gripping elements may be no greater than 2 millimeters. In some embodiments, each of the plurality of gripping elements may include a wide base that tapers toward the gripping surface. The gripping surface may be convex. The gripping surface may be concave. The height of each of the plurality of gripping elements may be no greater than 1 millimeter. The open area of the substrat