Verfahren und Vorrichtung zur Detektierung des Zustandes einer Polierscheibe

摘要

A single sensor 19 simultaneously measures the thickness and contour of a polishing pad 3 before and after polishing to determine changes in the thickness and contour of the polishing pad 3 caused by polishing. Based on these changes, a reproduction signal for pad reproduction or a replacement signal for pad replacement is output from a controlling means 13 to enable the surface accuracy of the polishing pad to be efficiently controlled.