Formation and interaction of dislocation-induced and vicinal monatomic steps on a GaAs(001) surface under stress relaxation

Abstract

Formation and interaction of curved vicinal and straight dislocation-induced steps of monatomic height on smooth GaAs(001) surface is studied under thermo-mechanical stress relaxation in GaAs/AlGaAs heterostructures bonded to glass. Typical dislocation phenomena, like transverse glide, are revealed in the slip steps patterns. At elevated temperatures, slip steps keep their straight shape, while curved vicinal steps acquire distinct small-scale (~10nm) undulations caused, presumably, by kink bunching. Annihilation of steps with opposite signs and anticrossing of slip steps with each other and with vicinal steps are studied.