Oxidation of ion implanted silicon carbide

Thermal oxidation has been investigated in virgin and ion implanted 6H-silicon carbide (SiC). Monocrystalline SIC has been irradiated with different ions (Si+, P+ and Al+) at a fluence sufficient to produce a continuous amorphous layer from the surface to a depth of 650 nm. The oxidation process has been performed in dry atmosphere at several temperatures and times. The oxide thickness has been measured with Rutherford backscattering spectrometry and ellipsometric measurements. The oxide thickness is larger when oxidation is performed in amorphized layers with respect to unimplanted regions. Oxidation of samples;amorphized with various ions of similar mass does not show any dependence on the ion species, suggesting that the enhanced oxidation rate is not related to the effect of the dopant, but to the breakdown of the strong covalent SIC bonds induced by the ion irradiation and to the resultant increase in chemical reactivity.