TiAl-based Ohmic Contacts to p-type 4H-SiC

This paper describes successfully formed ohmic contacts to p-type 4H-SiC based on titanium-aluminum alloys. Four different metallization structures were examined, varying in aluminum layer thickness (25, 50, 75, 100 nm) and with constant thickness of the titanium layer (50 nm). Structures were annealed within the temperature range of 800 degrees C - 1100 degrees C and then electrically characterized. The best electrical parameters and linear, ohmic character of contacts demonstrated structures with Al layer thickness equal or greater than that of Ti layer and annealed at temperatures of 1000 degrees C or higher.