Patent ID: 7141809

Claim:
A method for reciprocally transporting a workpiece, the method comprising the steps of: providing the workpiece on a scan arm, wherein the scan arm is operably coupled to a motor comprising a rotor and a stator, and wherein the rotor and stator are operable to individually rotate and counter-rotate about a first axis; generating an electromagnetic force between said rotor and said stator so as to induce rotation of said rotor, wherein the rotation of said rotor further induces rotation of said stator, and further wherein rotation of said rotor translates said scan arm such that the workpiece travels through the ion beam along a first scan path; and controlling the electromagnetic force generated between said rotor and said stator to selectively reverse the rotation of said rotor and thereby reciprocally transport the workpiece along the first scan path, wherein said stator rotates and counter-rotates about the first axis in reaction to the reciprocating transport of the workpiece.