A method of implanting a workpiece (100) in an ion implantation system (400) is provided. The method includes providing an extraction plate (101) adjacent to a plasma chamber (402) containing a plasma (140), such that the extraction plate extracts ions (102) from the plasma through at least one aperture (407) that provides an ion beam having ions distributed over a range of an angles of incidence on the workpiece. The method includes scanning the workpiece with respect to the extraction plate and varying a power level of the plasma during the scanning from a first power level to a second power level, wherein at a surface of the workpiece, a first beam width (Wl, W3) at a first power level is greater than a second beam width (W2) at a second power level.