The present invention discloses a method for manufacturing a semiconductor device, comprising: forming a gate stacked structure on a silicic substrate; depositing a Nickel-based metal layer on the substrate and the gate stacked structure; performing a first annealing so that the silicon in the substrate reacts with the Nickel-based metal layer to form a Ni-rich phase of metal silicide; performing an ion implantation by implanting doping ions into the Ni-rich phase of metal silicide; performing a second annealing so that the Ni-rich phase of metal to silicide is transformed into a Nickel-based metal silicide source/drain, and meanwhile, forming a segregation region of the doping ions at an interface between the Nickel-based metal silicide source/drain and the substrate. The method for manufacturing the semiconductor device according to the present invention performs the annealing after implanting the doping ions into the Ni-rich phase of metal silicide, thereby improving the solid solubility of the doping ions and forming a segregation region of highly concentrated doping ions, thus the SBH between the Nickel-based metal silicide and the silicon channel is effectively reduced, and the driving capability of the device is improved.