Abstract:
Thin films of ruthenium-on-6-hexagonal silicon carbide (6H-SiC) were analysed by Rutherford backscattering
spectroscopy (RBS) at various annealing temperatures. Some thin film samples were also analysed by scanning
electron microscope (SEM). RBS analysis indicated minimal element diffusion, and formation of ruthenium
oxide after annealing at 500 oC. Large scale diffusion of ruthenium (Ru) was observed to commence at 700 oC.
The SEM images indicated that the as-deposited Ru was disorderly and amorphous. Annealing of the thin film
improved the grain quality of Ru. The fabricated Ru-6H-SiC Schottky barrier diodes (SBD) with nickel ohmic
contacts showed excellent rectifying behaviour and linear capacitance-voltage characteristics up to an annealing
temperature of 900 oC. The SBDs degraded after annealing at 1000 oC. The degradation of the SBDs is
attributed to the inter-diffusion of Ru and Si at the Schottky-substrate interface.
