Effects of Si interlayer on nickel and platinum ohmic contacts for N-type SiC

Abstract

Platinum and nickel contacts with and without silicon addition were prepared and compared on 4H and 6H silicon carbide. After deposition, samples were gradually annealed up to 1150°C. Si addition into Pt contact was beneficial for decreasing of contact resistivity on 4H-SiC, but on 6H-SiC the effect was negligible. In the case of Ni-based contacts, the influence of Si was more pronounced for samples on 6H-SiC substrate, but after annealing at temperatures higher than 850°C similar values of contact resistivity were achieved for contacts with different Ni-Si ratio on both 4H and 6H-SiC.