Semiconductor-processing apparatus equipped with robot diagnostic module

A method for inhibiting defective wafers from being manufactured by detecting a deviation of an end effector of a wafer transfer robot for a semiconductor-processing apparatus that comprises:

• (i) a wafer transfer chamber provided with the wafer transfer robot therein, said wafer transfer chamber having multiple sides for attaching chambers thereto, (ii) at least one reactor attached to one side of the wafer transfer chamber and accessible to the wafer transfer robot, and (iii) a robot diagnostic module being a chamber shaped like the at least one reactor attached to another side of the wafer transfer chamber and accessible to the wafer transfer robot for diagnosing the transfer robot, said robot diagnostic module said robot diagnostic module being incapable of performing any processing of semiconductor wafers and comprising at least one sensor attached thereto for detecting a position of the end effector when the end effector is located inside the robot diagnostic module, wherein a relative position of the transfer robot at each reactor can be recreated inside the robot diagnostic module, said method comprising, while a wafer is being processed in the at least one reactor and the end effector of the wafer transfer robot is empty-handed or carrying a wafer:
• placing the end effector of the wafer transfer robot inside the robot diagnostic module;
• detecting a position of the end effector using the sensor;
• comparing the detected position with a pre-recorded reference position, thereby detecting a deviation of the end effector;
• and
• stopping processing a wafer when a deviation of the end effector is detected in the robot diagnostic module when comparing the detected position with the pre-recorded reference position.