An apparatus and method for partial ion implantation, which desirably provide control over the energy of the implanted dopants, generally includes an ion beam generator, and first and second deceleration units. The first deceleration unit decelerates the energy of an ion beam generated by the ion beam generator; and a subsequent, second deceleration unit further decelerates the energy into different energy levels according to regions of a wafer into which the ions are to be implanted.