Ti/Ni/Ti/Au ohmic contact to n-type 6H-SiC

We report a low temperature Ti/Ni/Ti/Au multilayered Ohmic contact to n-type 6H-SiC bulk sample. By using this simple metallization scheme and annealing at 750 °C, a low contact resistance is achieved for vertical conduction. Similar contact scheme on polished and unpolished sides of the bulk SiC substrate showed a difference in resistance due to different surface roughness. X-ray diffraction results of the alloyed contact layer show that formation of TiSi2 layer might be responsible for the Ohmic contact. The roughness of the contact surface on the polished side and unpolished sides are found to be 5 and 38 nm, respectively.