Characterization of cubic SiC films grown on thermally oxidized Si substrate

Abstract

The growth of cubic SiC films on the thermally oxidized Si substrate is studied by means of hydrogen plasma sputtering of a SiC target. The cubic SiC film without the hollow voids at the film/substrate interface can be grown on the SiO2 layer/Si substrate at 650 °C. The film has stoichiometric composition, and showed well-defined (111) growth at that temperature. There is an etching effect of hydrogen plasma on the substrate before a continuous film is formed over the substrate, and the etch rate depends strongly on the substrate temperature. The plasma etching results in both the breakage of the SiO2 layer and the loss of the substrate Si leading to the hollow voids at the film/substrate interface. There is also an atom migration process between the SiC film, the SiO2 layer, and the Si substrate during the growth of the films. At the substrate temperatures above 750 °C, the adsorbed C atoms diffuse into the Si substrate by different mechanisms, and result in the SiC islands in the Si substrate.