X-ray Photoelectron Spectroscopy Study of Silicon Interlayer Based Surface Passivation for AlGaAs/GaAs Quantum Structures on (111) B Surfaces

摘要

Applicability of the Si interface control layer (Si ICL)-based surface passivation to GaAs and AlGaAs (111)B surfaces was investigated. An in-situ X-ray photoelectron spectroscopy (XPS) study confirmed formation of the intended passivation structure. MBE grown GaAs and AlGaAs (111)B surfaces showed strong Fermi level pinning. After Si ICL growth, large shifts of the surface Fermi level position were observed. Photoluminescence (PL) measurements were also used to examine the surfaces of AlGaAs/GaAs quantum well and quantum wire structures grown on the GaAs (111)B substrates. PL intensity reduction caused by surface states was recovered remarkably by the Si ICL–based passivation.