Atomic Scale Interface Structure of In{sub 0.2}Ga{sub 0.8}As/GaAs Strained Layers Studied By Cross-Sectional Scanning Tunneling Microscopy

摘要: A molecular beam epitaxy-grown In{sub 0.2}Ga{sub 0.8}As/GaAs strained layer structure has been studied by scanning tunneling microscopy in cross-section on the (110) cleavage plane perpendicular to [001] growth direction. Individual indium atoms were differentially imaged group III sublattice, allowing, a direct observation of interface roughness due compositional fluctuation. In 0.8}As layers, Indium are found clusters preferentially along direction with each cluster containing 2--3 atoms. segregation induced asymmetrical broadening is an atomic scale. The grown GaAs sharp within 2--4 layers. be broadened about 5--10 scale fluctuation distribution 20 {angstrom} alone this case. authors conclude that clustering and main reason for roughness.