The diffusion behavior of vanadium （V） implanted in SiC is investigated by secondary ion mass spec- trometry. Significant redistribution, especially out-diffusion of vanadium towards the sample surface, is not ob- s...
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The diffusion behavior of vanadium （V） implanted in SiC is investigated by secondary ion mass spec- trometry. Significant redistribution, especially out-diffusion of vanadium towards the sample surface, is not ob- served after 1650℃ annealing. Higher carrier concentration is obtained due to a lack of compensation of vanadium in the surface region. The electrical characteristics of Ni contacts to V-implanted n-type 4H-SiC are investigated using a linear transmission line method. A specific contact resistance as low as 4.4 × 10^-3Ω · cmA^2 is achieved after annealing at 1050℃ for 10min in gas ambient consisting of 90% N2 and 10% H2 X-ray diffraction analysis shows the formation of Ni2 Si and graphite phase at the interface after annealing. This provides the evidence that the car- bon vacancies,resulting from the out-diffusion of carbon atoms from SiC, contribute to the formation of ohmic contact through the reduction of effective Schottky barrier height for the transport of electrons.
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