Retaining ring for cmp

Abstract

A retaining ring includes a generally annular body having an inner surface to constrain a substrate and a bottom surface, the bottom surface having a plurality of channels extending from an outer surface to the inner surface, and a plurality of islands separated by the channels and providing a contact area to contact a polishing pad, wherein the contact area is about 15-40% of a plan area of the bottom surface.

Description

technical field [0001] The present disclosure relates to a retaining ring of a carrier head for chemical mechanical polishing. Background technique [0002] Integrated circuits (especially silicon wafers) are usually formed on a substrate by successively depositing conductive, semiconducting or insulating layers. One fabrication step includes depositing a filler layer on a non-planar surface and planarizing the filler layer. For some applications, the filler layer is planarized until the top surface of the patterned layer is exposed. For example, a conductive filler layer may be deposited on the patterned insulating layer to fill trenches or holes in the insulating layer. After planarization, the portions of the conductive layer left between the raised patterns of the insulating layer form vias, plugs and wires that are provided between the thin film circuits on the substrate. conductive path. For other applications such as oxide polishing, the filler layer is planarized...

AI Technical Summary

Problems solved by technology

However, because the retaining ring contacts the polishing pad, the retaining ring is prone to wear and occasional replacement of the retaining ring

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