Electrochemical growth of ultraflat Au(111) epitaxial buffer layers on H–Si(111)

Thin metal layers deposited on a substrate (buffer layers) are widely employed in many fields of research and in microelectronic industry. In this work we present x-ray diffraction measurements and atomic force microscopy observations which demonstrate that high quality ultrathin Au(111) epitaxial films can be electrodeposited from a gold chloride solution on a well-defined H-terminated vicinal Si(111) surface. In addition, the obtained films present no apparent grain boundary. This result, which seems in conflict with classical growth theory, requires applying unconventional electrodeposition conditions in which a strong hydrogen evolution reaction is promoted.