In this study, the formation of Ni, Ni-rich Ni2Si and Si-rich NiSi2 ohmic contacts to n-type 4H-SiC are investigated. The Ni/n-SiC ohmic contact with resistance rc ~ 4.2×10-4 Ω cm2 is formed after annealing at 1050oC. For Ni2Si/n-SiC, the contact resistances were rc ~ 4×10-4 Ωcm2 and rc ~ 3.5×10-4 Ωcm2 after annealing at 1000 and 1050oC, respectively. The non-ohmic I-V characteristics are observed for NiSi2/n-SiC contact even after annealing at 1050oC. The features of ohmic contact formation for Ni-based metallization to 4H n-SiC are discussed.