Strong binding at the gold (Au) boron carbide interface

We have investigated the interaction of gold (Au) with the semiconductor boron carbide through X-ray photoemission. Hydrogenated semiconducting boron carbide films, deposited by plasma enhanced chemical vapor deposition (PECVD) of closo-1,7-dicarbadodecaborane (metacarborane, m-B10C2H12), show a shift in the binding energies of the core level photoemission features when Au is deposited on the surface. The shifting of the B 1s level is smaller than for the C 1s level and the non-uniform nature of the shifts indicates a strong, complex and reversible Au chemical interaction with the surface, particularly with the C sites. Capacitance versus voltage, C(V) and current versus voltage, I(V), results for the film deposited on p-type Si(100) yield a carrier scattering time of 50ns, significantly smaller than the 35μs for the PECVD orthocarborane boron carbide films.