Patent ID: 8666551

Claim:
A semiconductor-processing apparatus comprising: a wafer transfer chamber provided with a wafer transfer robot therein, said wafer transfer robot having an end effector for carrying a wafer, said wafer transfer chamber having multiple sides for attaching chambers thereto; at least one reactor attached to one side of the wafer transfer chamber, and accessible to the wafer transfer robot; and a robot diagnostic module being a chamber shaped like the at least one reactor which is attached to another side of the wafer transfer chamber and accessible to the wafer transfer robot to diagnose the transfer robot inside the robot diagnostic module while a wafer is being processed in the at least one reactor and the end effector of the transfer robot is empty-handed or carrying a wafer, 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.