SYSTEM FOR PREVENTING SEMICONDUCTOR WAFER FROM BEING OVERLAPPED

摘要

PURPOSE: A system for preventing a semiconductor wafer from being overlapped is provided to control a robot unit by automatically determining the existence of the wafer when the wafer is transferred by a robot arm or is stacked in a cassette. CONSTITUTION: The robot unit transfers the wafer. The wafer is stacked in the cassette. The cassette is placed by a locator. A position detecting light emitting sensor unit(50) that detects the existence of the wafer and is capable of being seen by the naked eye is installed in an end of an arm(21) of the robot unit(20). An interlock unit stops the system by using a signal received from the sensor unit. A robot driver controls the robot unit that transfers the wafer by using the signal received from the sensor unit.