Highly conductive nitrogen-doped hydrogenated nanocrystalline cubic silicon carbide thin films prepared with a hot-wire chemical vapor deposition from SiH4/CH4/H2/N2 gas

Nitrogen-doped hydrogenated nanocrystalline cubic silicon carbide (nc-3C-SiC:H) thin films were prepared with a hot-wire chemical vapor deposition from SiH4/CH4/H2/N2 and the influences of the N2 and H2 gas flow rates on the structural and electrical properties were investigated. As the N2 gas flow rate, F(N2), was increased, the intake of the N atoms increased, resulting in the deterioration of the structural order of the nc-3C-SiC:H thin films. At a low H2 gas flow rate, F(H2), of 200 sccm, the conductivity increased with increasing F(N2) up to 20 sccm and deteriorated with increasing F(N2) of 20–50 sccm. The former was due to the increase in the intake of N atoms and the latter was due to the deterioration of the structural order. At a high F(H2) of 1000 sccm, the degree of the deterioration of the structural order was low compared to that at F(H2) of 200 sccm. The conductivity therefore improved even at high F(N2) of 50–150 sccm. A high conductivity of 5.0 S/cm was achieved at F(N2) = 100 and F(H2) = 1000 sccm.