The end‐of‐range defects for Si, P, Ge, and As implantations were evaluated by transmission electron microscopy over a range of implant doses. The results for P and As closely tracked those for Si and Ge, respectively. As the implant dose is increased, the defects increase slightly for Si and P but significantly for the heavier Ge and As atoms. For implant doses just above the critical value for amorphization, the defect concentration for the lighter Si and P atoms is about five times as great as for the Ge and As. The advantage of using low dose Ge postamorphization is discussed.