Structure and composition of silicon carbide films synthesized by ion implantation

The mathematical decomposition of the IR absorption spectrum obtained from a Si layer after the C⁺ ion implantation with an energy of 10 or 40 keV or from a homogeneous SiC_0.7 film has demonstrated that fractions of weak elongated Si-C bonds in the amorphous phase, strong shortened Si-C bonds on the surface of small nanocrystals, and tetrahedral Si-C bonds in the crystalline phase (degree of crystallinity) after high-temperature annealing (1250–1400°C) of the layers are equal to 29/29/42, 22/7/71, and 21/31/48%, respectively. A system of SiC_2.0, SiO₂, SiC_0.8, and SiC_0.6 layers in the film on the Si substrate has been identified using X-ray reflectometry and the simulation with the Release software. The reflectometry data on fluctuations of the intensity of X-ray reflections in the region of the main maximum have been interpreted in terms of variations in the density over the depth of the layer with a Gaussian distribution of carbon atoms from 2.55 and 2.90 g/cm³ for the SiC_0.25 and SiC_0.65 layers, respectively, to 3.29 g/cm³ for the SiC_1.36 layer.