Computational Insights into the Energetics of Single C2-C10 Aliphatic Moieties Adsorbed on Hydrogenated Silicon (111) Surface

Silicon's versatility as a semiconductor renders it indispensable across various domains, including electronics, sensors, and photovoltaics. Modifying hydrogen-terminated silicon surfaces with moieties adsorption offers a method to tailor the material’s properties for specific applications. In this study, we employ ab initio density functional theory calculations to explore the energetics of single alkyl, 1-alkenyl and 1-alkynyl moieties adsorbed on H-terminated Silicon (111) surface. We analyse the interfacial dipole induced by Si–C bond formation that determines the Schottky barrier and examine the alignment of the frontier orbitals energy levels with silicon band structure related to the charge transfer tunnelling mechanism. Our findings provide valuable insights into how aliphatic moiety functionalization affects interfacial electronic properties, offering clues for optimizing silicon-based devices.