Patent ID: 8060252
Filing Date: 2011-11-15
Classification: H01L

Abstract:
1. A method of transferring wafers from a first location to a second location, comprising: extending a dual end effector arm of a first robot to a first location having first and second side-by-side wafers to pick the wafers such that each wafer is supported by an end effector; retracting the dual end effector arm along a nominal path transferring the dual end effector arm along a nominal path to an intermediate station; extending the dual end effector arm along a nominal path to simultaneously place the wafers at the intermediate location; wherein position information of the wafers relative to the end effectors is measured at some point during the nominal retraction, transfer or extension moves; sending the position information to a second robot and receiving the position information with the second robot; picking the first wafer from the intermediate location with a first end effector of the second robot, wherein the position of the first end effector of the second robot during the pick move is adjusted based on the received position information; picking the second wafer from the intermediate location with a second end effector of the second robot, wherein the position of the second end effector of the second robot during the pick move is adjusted based on the received position information; transferring the wafers to the second location along a nominal path; and simultaneously placing the wafers at the second location.