The present disclosure provides a method of achieving an integral number of sweeps within an ion beam. A substrate having a fiducial is placed on a wafer stage within the ion beam system. An energetic particle beam is generated within the ion beam system. The substrate is exposed to the energetic particle beam while the wafer stage with the substrate is rotated clockwise so that the fiducial of the substrate travels a sweep distance in a clockwise direction at a first speed and the fiducial of the substrate travels the same sweep distance in a counterclockwise direction at a second speed. The exposure of the substrate to the energetic particle beam is discontinued when the number of complete/full sweeps in the clockwise direction equals the number of complete/full sweeps in the counterclockwise direction.