In-process tape bur monitoring

The protective tape applied to the front surface of a semiconductor wafer to protect the wafer during backgrinding must be trimmed so that excess tape, known as tape bur, does not extend beyond the perimeter of the wafer. Tape bur may interfere with backgrinding by causing improper grinding, which may lead to wafer breakage. The tape cutter that trims the protective tape to eliminate tape bur is provided with a sensor which detects whether tape bur has been trimmed from the wafer. If tape bur has not been removed from the wafer, corrective action is taken to prevent the wafer from being backgrinded.