Silicon wafers were implanted with iron ions at different fluences (from 5×10 15 up to 2×10 17 cm −2 ), followed by annealing treatments at temperatures from 550°C to 1000°C, aiming at evaluating the nanomechanical response of the samples and its relation with the microstructural features and characteristics of the modified layer. After implantation, a homogeneous amorphous layer with a thickness between 200nm and 270nm is formed, without damaging the surface smoothness neither introducing surface defects. After annealing, recrystallization and formation of nanometric precipitates of iron silicides is observed, with the corresponding changes in the hardness and stiffness of the modified layer. These results indicate that ion implantation of silicon followed by annealing at proper temperatures, can be an alternative route to be deeper explored in what concerns the precise control of the microstructure and, thus, the improvement of nanomechanical properties of silicon.