An ion implantation system, including an ion source and extraction system, arranged to generate an ion beam at a first energy, and a linear accelerator, disposed downstream of the ion source, the linear accelerator arranged to receive the ion beam as a bunched ion beam accelerate the ion beam to a second energy, greater than the first energy. The linear accelerator may include a plurality of acceleration stages, wherein a given acceleration stage of the plurality of acceleration stages comprises: a drift tube assembly, arranged to conduct the ion beam; a resonator, electrically coupled to the drift tube assembly; and an RF power assembly, coupled to the resonator, and arranged to output an RF signal to the resonator. As such, the given acceleration stage does not include a quadrupole element.