Patent ID: 6678581
Filing Date: 2004-01-13
Classification: H01L

Abstract:
A method of calibrating a wafer edge gripping end effector comprising:providing a wafer calibration tool that is substantially disc shaped having an outer edge with a plurality of notches formed therein, wherein each notch is defined in part by an inner edge constructed and arranged to simulate the outer edge of a semiconductor wafer to be gripped by a wafer edge gripping end effector; providing a robot having a robot arm and a wafer edge gripping end effector connected thereto, and a controller for controlling the movement of the robot arm and the wafer edge gripping end effector, and wherein the wafer edge gripping end effector includes a main base portion and a first finger and a second finger each extending from the main base portion and wherein the first and second fingers are spaced apart from each other, and wherein each finger has a free end, and a first clamp structure position on the first finger near the free end of the first finger, and a second clamp structure positioned on the second finger near the free end of the second finger, and a third clamp structure, and wherein at least one of the first, second and third clamp structures is movable, and an actuator for moving the movable clamp structure, and wherein the actuator is controlled by the controller, and the controller having a memory for storing data regarding the position of the robot arm, end effector, and movable clamp structure, and the controller constructed and arranged to be turned on and off; holding the wafer calibration tool in a stationary position simulating the position of a semiconductor wafer to be picked up by the wafer edge gripping end effector; turning off the controller; moving the robot arm and end effector to a position wherein the first and second clamp structures each engage a respective inner edge that in part defines one of the notches in the wafer calibration tool; advancing the movable clamp structure so that the movable clamp structure engages an inner edge that in part defines one of the notches in the wafer calibration tool; turning on the controller and storing data in the memory regarding the location of the robot arm, end effector, and movable clamp structure.