Cross-sectional transmission electron microscopy was used to study defect formation and evolution in the (001) Ge and Si wafers implanted with 1 MeV Si+ and 40 keV Si+ at a dose of 1x10(14) cm(-2). As expected, upon annealing, the {311} extended defects form and subsequently dissolve at the projected range for nonamorphizing implants into Si. However, in Ge, no {311} defect formation is observed for this nonamorphizing implant after annealing at temperatures between 350 and 850 degrees C. Instead, for the MeV implant, small dotlike defects are observed in Ge, which dissolve upon annealing between 650 and 750 degrees C for 10 min. (c) 2008 American Vacuum Society.