Hydrogen termination of the NH4F-treated Si(111) surface studied by photoemission and surface infrared spectroscopy

Abstract
The Si(111) surface treated in a saturated solution of NH4F has been investigated using photoemission spectroscopy with synchrotron radiation and surface infrared spectroscopy (SIS) in the multiple internal reflection mode. Photoemission and SIS data clearly demonstrate that the NH4F‐treated Si(111) surface is dominantly terminated with the monohydride Si (Si‐H) oriented perpendicular to the surface and is free from silicon oxide. It is suggested that the absence of silicon oxide is closely related to the atomic flatness of this surface.