Localized CMP to improve wafer planarization

摘要

To provide improved planarization, techniques in accordance with this disclosure include a CMP station that utilizes localized planarization on a wafer. This localized planarization, which is often carried out in a localized planarization station downstream of a CMP station, applies localized planarization to less than the entire face of the wafer to correct localized non-planar features. Other systems and methods are also disclosed.

主权项

1. A method of chemical mechanical polishing (CMP), comprising:
performing chemical mechanical polishing on a wafer to provide a substantially planar wafer surface, wherein the substantially planar wafer surface includes first and second non-planar features that are spaced apart from one another by a substantially planar surface region; analyzing the substantially planar wafer surface to detect the first and second non-planar features thereon; providing a polishing pad having a surface area that is smaller than a surface area of the wafer; moving the polishing pad along a polishing pad axis, which is continuously perpendicular to the substantially planar wafer surface, until the polishing pad surface is proximate to the first non-planar feature; rotating the polishing pad surface about the polishing pad axis to locally planarize the first non-planar feature without performing localized planarization of the substantially planar surface region between the first and second non-planar features; and lifting the polishing pad surface along the polishing pad axis when the localized planarization of the first non-planar feature is complete.