High temperature thermal stability of Au/Ti/WSix Schottky contacts on n-type 4H-SiC

Abstract The thermal stability of Au/Ti/WSi x contacts on 4H-SiC was examined by Auger electron spectroscopy and current–voltage measurements. The silicide-based contacts on SiC are found to exhibit improved thermal stability compared to pure W contacts. The Au/Ti/WSi x contacts show a maximum Schottky barrier height of ∼1.15 eV as obtained from current–voltage ( I – V ) measurements. After 500 °C anneals, the Ti diffuses to the surface of the contact structure, followed by a Au-rich layer and finally the WSi x . After 1000 °C anneals, the Ti and Au showed significant mixing. Particulates formed on the surface in the latter case were Au-rich phases.

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