Abstract: An ion implanter includes an ion source for generating an ion beam moving along a beam line and a vacuum or implantation chamber wherein a workpiece, such as a silicon wafer is positioned to intersect the ion beam for ion implantation of a surface of the workpiece by the ion beam. A liner has an interior facing surface that bounds at least a portion of the evacuated interior region and that comprises grooves spaced across the surface of the liner to capture contaminants generated within the interior region during operation of the ion implanter.