A work piece transfer apparatus for use with an ion beam implanter for treating a work piece at sub-atmospheric pressure. The work piece transfer apparatus includes an evacuable load lock system in fluid communication with an interior region the implantation chamber interior region. The load lock system includes a support surface for supporting the work piece with an opening aligned with the work piece. The work piece transfer apparatus further includes a work piece support within the implantation chamber having a pedestal supported by a linkage with two degrees of freedom. The linkage moves the pedestal transversely through the load lock support surface opening to pick up the work piece from the support surface prior to treatment. The pedestal holds the work piece in position in the implantation chamber for treatment. The linkage then moves the pedestal transversely through the load lock support surface opening to deposit the work piece on the support surface subsequent to treatment.