## 3 Results  
The experimental conditions of the various experiments and the thicknesses of the obtained films are shown in Table 1 as well as in Figure S1. The samples obtained under different conditions will be denoted with a capital letter O (those with natural oxide) or C (those with a deeply cleaned surface) and a numerical designation 3, 5, 20, 60, or 90, depending on the duration in minutes of the carbonization process. To measure the thickness of the thin films using AFM and the Talystep profilometer, the films were marked by scratching with a hardened steel needle. However, the resulting scratches lack a clearly defined flat transition between the layer and the substrate, significantly complicating the accurate determination of scratch depth. Additionally, localized areas (approximately 3 \(\times\) 3 mm\({}^{2}\)) were ablated using laser radiation. For this purpose, the fourth harmonic (\(\uplambda\) = 266 nm) of a nanosecond Nd:YAG laser system (fundamental wavelength \(\uplambda\) = 1064 nm, frequency = 10 Hz, pulse duration = 15 ns, energy = 14 J/cm\({}^{2}\)) was applied for 2-5 s, depending on the carbonization time (3-90 min). Studies conducted using both methods confirmed the impossibility of selectively removing only the thin film down to the thin film/Si-substrate interface. We attribute the failure of mechanical cleavage to the excellent adhesion of the thin films to the substrates. Similarly, the challenges encountered in laser ablation can be linked to the significant surface roughness of the ablated area. Difficulties in phase visualization in electron microscopy arise due to the close atomic numbers of Si, O, and C as well as those of SiC and Si-O-C glasses with variable composition. Given these limitations, we consider the results obtained from the indicated measurements to be insufficiently reliable; therefore, they are not presented here. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Experiment** & **Plasma** & **Deposition Time (min)** & **CH4 Gas Flow (sccm)** \\ \hline C3 & + & 1 \(\times\) 3 & 10 \\ O3 & + & 1 \(\times\) 3 & 10 \\ C5 & + & 1 \(\times\) 5 & 10 \\ O5 & + & 1 \(\times\) 5 & 10 \\ C20 & + & 1 \(\times\) 20 & 10 \\ O20 & + & 1 \(\times\) 20 & 10 \\ C60 & + & 1 \(\times\) 60 & 10 \\ O60 & + & 1 \(\times\) 60 & 10 \\ C90 & + & 1 \(\times\) 90 & 10 \\ O90 & + & 1 \(\times\) 90 & 10 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: The summarized data on the experimental conditions of the various experiments and the thicknesses of the deposited films. The thickness of the synthesized thin films C3, C5, O3, and O5 was determined by ellipsometric measurements, and it is 12, 12, 13.5, and 15 nm, respectively. To maximize the precision of the fits, we used as input parameters the results of the XPS and GDOES studies on the composition of the films, and they were approximated with layers containing 4H-SiC and Si-C-O glass, assuming the absence of a discrete SiO\({}_{(2-x)}\) phase. The presumed change in the thin film composition in depth and the poorly defined interface make this approximation inapplicable to the ellipsometric analysis of films synthesized for 20 min or longer. In these cases, the thickness data for the samples C20, O20, C60, O60, C90, and O90 obtained by AFM, profilometry, and ellipsometry differ significantly, and for this reason, concrete values are not indicated. The powder XRD patterns taken in (\(\theta\)\(-\)2\(\theta\)) scans of the synthesized films C3, C5, C60, C90, and O90 (Figure 1) show the formation of clearly structured crystallites of polycrystalline SiC, especially in the longer experiments C90 and O90. The XRD patterns of C90 and O90 are indexed in the hexagonal cell of the 36H polytype of SiC [25], which possesses trigonal symmetry (space group (SG) #156 and cell parameters a\({}_{0}\) = 3.0730 A, c\({}_{0}\) = 90.6500 A).