Surface segregation of third-column atoms in III–V ternary arsenides

Abstract We report a systematic study by in situ electron spectroscopies of the segregation to the surface of third-column atoms in ternary arsenides (GaA1As, InA1As, InGaAs) grown by molecular beam epitaxy. We find an important surface enrichment leading to a near-binary surface: InAs for InA1As and InGaAs even for Ga-rich bulk materials, GaAs for GaA1As. The tendency of third-column atoms to surface segregation in ternary alloys is summarized by the relation In > Ga > A1 as in heterostructures between binary arsenides.