Abstract: An algorithm of trajectory overlay planning is investigated for step-move and scan-move of step-scan lithography. Based on system dynamic constraints, several criteria of trajectory overlay planning are constructed to ensure motion parameters planned within its preset values respectively. All available instances of trajectory overlay planning are discussed, and relevant equations are further derived. As a result, the algorithm of trajectory overlay planning for step-move and scan-move is presented. The correctness and effectiveness of the algorithm are demonstrated by simulation calculation and practical results. High productivity and high motion accuracy are obtained by applying the presented method. This algorithm has been applied in the motion control system of 100 nm step-scan lithography successfully.

Key words: Limitation criteria, Overlay, Step-move and scan-move, Trajectory planning