Abstract: By appropriately controlling the surface quality of a silicon wafer and using the electrical sparking technique, high boron-alloy (BAlNiIn) and high phosphorus-alloy (PSbAuIn) can simply be used to make good ohmic contacts on silicon materials of resistivity as high as 20000Ωcm and 4000Ωcm for the P-type and N-type, respectively. Even after 30 times of temperature circulation from 300 K to 77 K, the linear I-V property of the ohmic contacts still remains. The ohmic contact formations and carrier transport characteristics are discussed, based on the current-voltage and specific contact resistance measurements at different temperatures, the ion microprobe analysis, and the calculation of specific contact resistance of metal to silicon as a function of doping concentration. This method has been successfully applied to the measurements of impurity compensation and carrier mobility on high resistivity silicon materials.