Germanium has regained attention in the semiconductor industry for MOSFET application because of the higher mobility of carriers – two times higher mobility for electrons and four times for holes – as compared to silicon. In the opposite of the Silicon, the major issue with Germanium is to limit the n-dopant diffusion. Usual n-dopants (Phosphorus and Arsenic for example) are not electrically activated at an acceptable level without a large diffusion of the doping profile and a substantial dose loss. In this work, we have studied the influence of low energy and dose implant (15KeV to 40KeV @ 8E13 to 1E15at.cm−2) and low temperature anneal (515°C to 600°C) on diffusion, exodiffusion and activation of the phosphorus dopant into Germanium. The annealing steps were made in RTP furnace, the chemical profile and electrically active profiles were extracted by using Secondary-Ion-Mass Spectroscopy (SIMS) and sheet resistance measurement (Rs). To investigate the implantation-induced defects in depth, cross-sectional micrographs were made by using Transmission Electron Microscopy (TEM). Experimental results show that we achieved an efficient activation level by tuning both dose implant and anneal temperature, limiting the exodiffusion with pratically no diffusion of the dopant. We also show that very abrupt profile can be achieved with appropriate implant and thermal annealing conditions. To limit the leakage current in devices, we suppose we have to limit the defects generated during the implantation. Specially for dopant activation temperature anneal below 550°C, we have shown and observed by cross-sectional micrograph that the defects are totally removed by addition of a pre step of annealing at 400°C.