Abstract
In magneto-plasma-dynamic (MPD) arcjet generators, plasma is accelerated by electromagnetic body forces. Silicon nitride reactive deposition was carried out using an MPD arcjet generator with crystal silicon rods and nitrogen gas. Because the MPD arcjet generator produces higher-velocity, higher-temperature, higher-density and larger-area plasmas than those with conventional thermal plasma torches, nitriding of silicon can be enhanced. A dense and uniform β-Si3N4 film of 30μm in thicknes was formed after 200 shots at a repetitive frequency of 0.05 Hz with a discharge current of 9 kA and a substrate temperature of 700 °C. The Vickers hardness reached about 1300. It was found that film thickness was highly sensitive to discharge current and that microstructure of the film was sensitive to the substrate temperature. These results show that the MPD arcjet generator has high potentials for silicon nitride deposition.
