Alkyl-terminated Si(111) surfaces: A high-resolution, core level photoelectron spectroscopy study

Abstract
The bonding of alkyl monolayers to Si(111) surfaces has been studied with high-resolution core level photoelectron spectroscopy (PES). Two very different wet-chemical methods have been used to prepare the alkyl monolayers: (i) Olefin insertion into the H–Si bond of the H–Si(111) surface, and (ii) replacement of Cl on the Cl–Si(111) surface by an alkyl group from an alkyllithium reagent. In both cases, PES has revealed a C 1s component shifted to lower binding energy and a Si 2p component shifted to higher binding energy. Both components are attributed to the presence of a C–Si bond at the interface. Along with photoelectron diffraction data [Appl. Phys. Lett. 71, 1056, (1997)], these data are used to show that these two synthetic methods can be used to functionalize the Si(111) surface.