Graphitic carbon thin film growth from ion-beam-amorphised 6H-SiC

Ion-beam-induced amorphisation of crystalline 6H-SiC was investigated as a route to graphitic carbon thin-film growth during high-temperature vacuum annealing. A near-surface ion-beam-amorphised SiC region approximately 200 nm thick was produced by 360 keV Cs + ion implantation at a fluence of 1 × 10 16 cm −2 , followed by annealing at 1450–1750 °C. Rutherford backscattering spectrometry (RBS) and X-ray photoelectron spectroscopy (XPS) revealed progressive Si depletion and carbon enrichment with increasing annealing temperature. XPS depth profiling indicated thicknesses of 37 and 48 nm for the carbon thin films formed at 1450 and 1550 °C, respectively, whereas at 1650 and 1750 °C the film thickness exceeded the ~300 nm analysed depth. Spatially resolved Raman mapping revealed increasing in-plane ordering of the graphitic carbon thin films, with I(D)/I(G) decreasing from approximately 1.0–1.25 ± 0.06 at 1450–1550 °C to ~0.35–0.38 ± 0.02 at 1650–1750 °C, accompanied by an increase in estimated in-plane crystallite size, L a , from approximately 4–5 ± 0.23 nm to 13–14 ± 0.68 nm and narrowing of the G and 2D bands. The estimated compressive-strain contribution also decreased with increasing annealing temperature. Atomic force microscopy (AFM) measurements revealed increasing surface roughness at higher annealing temperatures, while tip-sample adhesion force and peak tip-sample interaction force showed non-monotonic changes across the annealed samples. These results show that preferential Si removal from ion-beam-amorphised SiC is accompanied by carbon enrichment and progressive development of an increasingly ordered graphitic carbon thin film.