In this paper, we investigated electrical and physical characteristics of nickel silicide using rare-earth metals(Er, Yb, Tb, Dy), Incorporated Ytterbium into Ni-silicide is proposed to reduce work function of Ni-silicide for nickel silicided schottky barrier diode (Ni-silicided SBD). Nickel silicide makes ohmic-contact or low schottky barrier height with p-type silicon because of similar work function (${phi}_M$) in comparison with p-type silicon. However, high schottky barrier height is formed between Ni-silicide and p-type substrate by depositing thin ytterbium layer prior to Ni deposition. Even though the ytterbium is deposited below nickel, ternary phase $Yb_xN_{1-x}iSi$ is formed at the top and inner region of Ni-silicide, which is believed to result in reduction of work function about 0.15 - 0.38 eV.