In this paper，combinatorial method was introduced for the first time to disclose the effect of Ni thickness on the Ni/SiC contact properties. Sixteen contacts with the same Ni thickness showed similar Schottky contact properties.The current voltage curves (I-V) were different for the Schottky contacts with different Ni thickness from 10 nm to 160 nm. The effect of the Ni thickness to the ideality factor n and the effective barrier height ФB was found to be the origin of the different Schottky contact properties. After rapid annealed at 1000℃，all the contacts showed good linear I-V curves，which indicated the formation of ohmic contacts. Ni2Si was the main reaction product. Comparing the slopes of the IV curves，the contacts with 30—70 nm Ni showed good ohmic contact properties. The results confirmed our previous conclusion about the key role of appropriate carbon-enriched layer (CEL) for the formation of ohmic contacts on SiC.