Ni-Al Ohmic contact to p-type 4H-SiC

International audienceInvestigations on Ni-Al alloys to form ohmic contacts on p-type 4H-SiC are presented in this paper. Several ratios of the Ni/Al contact were examined. Rapid thermal annealing was performed in Argon atmosphere at 400°C during 1 minute, followed by an annealing at 1000°C during 2 minutes. In order to extract the specific contact resistance, transmission line method (TLM) test-structures were fabricated. A specific contact resistance of 3×10-5 Ω.cm2 was obtained reproducibly on p-type layers, with a doping of NA = 1×1019 cm-3 performed by Al2+ ion implantation. The lowest specific contact resistance value measured was 8×10-6 Ω.cm2