Synthesis of SiC thin films on Si substrates by ion-beam sputtering

Abstract

We synthesized β-SiC thin films on a Si substrate surface by the ion-beam sputtering of a two-component graphite-silicon target. The smooth film surface and abrupt SiC film-Si substrate interface allow determination of the SiC film parameters by X-ray reflectometry. The Henke-Gullikson simulation shows that the synthesized SiC0.8 film has a thickness of d = 160 nm, a density of ρ = 3.03 g/cm3, and a roughness of σ = 0.25 nm. X-ray diffraction and IR spectroscopy show the formation of β-SiC crystallites about 5.5 nm in size in the SiO0.8 and amorphous SiO2 layers after annealing at a temperature of 1250°C in an Ar atmosphere with O2 inclusions. Simulation using the Release program shows that etching in HF acid for 5 min leads to the formation of a system containing a smooth high-density thin carbon film. The system composition is C(d = 4.0 nm, ρ = 3.7 g/cm3, σ = 0)/SiC0.8(d = 75.0 nm, ρ = 3.03 g/cm3, σ = 2.0 nm)/a-Si(d = 3.0 nm, ρ = 2.23 g/cm3, σ = 4.5 nm)/Si(d = ∞, ρ = 2.33 g/cm3, σ = 0.6 nm).