System zum Kontrollieren der Leitfähigkeit eines Halbleiterplättchens während des Schleifens.

摘要

An apparatus for monitoring the conductivity of a semiconductor wafer (2) during the course of a polishing process is disclosed. A polishing pad (22) that contacts the wafer has an active electrode (26) and at least one passive electrode (28), both of which are embedded in the polishing pad. A detecting device (34, 36, 38, 40, 41) is connected to the active and passive electrodes for monitoring the current between the electrodes as the wafer is lapped by the polishing pad. The etch endpoint of the wafer is determined as a function of the magnitude of the current flow.