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A highly two-dimensional and chemically pure MgO (111) thin film grown epitaxially under ultra-high vacuum on a (√3 × √3) R30° reconstructed wideband gap 6H-SiC (0001) substrate surface can serve as a promising minimal mismatch interfacial layer between the substrate surface and a crystalline structure of functional oxide film. However, the reliability and repeatability of the growth process is challenging. In this paper the dynamic termination of the MgO (111) polar oxide during layer-by-layer growth is explained by OH group chemical bonding state of MgO structure. The analysis of causal relationships is conducted at three different thickness levels to account for the sensitivity of film chemistry to the mismatching strain related inherent twist of crystalline structure along the film thickness. The contribution of sources of the undesired bonding states is quantified by examining the process sensitivity trends to the most critical process variable (percentage starting oxygen) at different thickness levels.

Surface preparation of silicon carbide (SiC) is critical to producing silicon carbide based wide bandgap semiconductor for electronic devices operating in high temperatures and/or harsh environments. In this research we study the impact of cleaning time and cleaning temperature on reflection high energy electron diffraction-based structural and X-ray photoelectron spectroscopy based stoichiometric performance indicators. We used a neural network assisted Monte Carlo analysis of the high temperature hydrogen etching procedure. We observed that the optimum cleaning time and temperature ranges for structural and stoichiometric analyses corroborate generally. The detailed examination of the stoichiometric analysis points to narrow parameter ranges where both optimum surface chemistry and (√3 × √3) R30° reconstruction of the structure of the surface can be achieved. A range of 1,400–1,500°C cleaning temperature for a time period of 14–20 minutes was found to consistently result in (√3 × √3) R30° reconstruction with an optimum oxygen content.