The present invention discloses a method for manufacturing a
semiconductor device, comprising: forming a gate stacked structure on a substrate; forming a source / drain region and a gate sidewall spacer at both sides of the gate stacked structure; depositing a
Nickel-based
metal layer at least in the source / drain region; performing a first annealing so that the
silicon in the source / drain region 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
metal silicide is transformed into a
Nickel-based
metal silicide, and meanwhile, forming a segregation region of the
doping ions at an interface between the Nickel-based metal
silicide and the source / drain region. The method 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 of the metal-
semiconductor contact between the Nickel-based metal silica and the source / drain region is effectively reduced, the
contact resistance is decreased, and the driving capability of the device is improved.