Electronic passivation of GaAs surfaces through the formation of arsenic—sulfur bonds

Abstract
X‐ray photoelectron spectroscopy reveals that the remarkable electronic quality of GaAs/sulfide interfaces can be ascribed to the formation of AsxSy phases which grow on an oxide‐free GaAs surface. While one of these phases is akin to As2S3, another shows significant in‐plane S—S bonding. Raman experiments indicate that the band bending on this disulfide‐ terminated surface has been reduced to 0.12 eV.