Silicon is the most diffused material for microelectronic industry and, in recent times, it is becoming more and more widespread in integrated optic and optoelectronic fields. Nowadays it is possible to realize in silicon, using the traditional microelectronic techniques, a huge variety of passive and active devices, like waveguide, switch, modulators, whose operation range is in the second and third optical telecommunication windows. In this poster we propose a simulation of an integrated waveguide-vanishing-based modulator realized by ion implantation in SOI wafer. The active region is 3x3 micron wide and the lateral confinement is guaranteed by two highly-doped As (8×10+19 cm-3) and B (2×1019 cm-3) implanted regions with a depth of one micron. This type of structure allows to obtain a planar device; thus an easier integration with electronic devices is possible to obtain. The implantation process has been …