Chemical mechanical polishing endpoint detection

摘要

The methods and systems described provide for an in-situ endpoint detection for material removal processes such as chemical mechanical processing (CMP) performed on a workpiece. In a preferred embodiment, an optical detection system is used to detect endpoint during the removal of planar conductive layers using CMP. An optically transparent polishing belt provides endpoint detection through any spot on the polishing belt. Once endpoint is detected, a signal can be used to terminate or alter a CMP process that has been previously initiated.