Atomic-scale view of AlGaAs/GaAs multilayers with cross-sectional scanning tunneling microscopy

Atomically-resolved cross-sectional topographic images of AlGaAs/GaAs multilayers, which includes a sequence of 1, 2, 5, and 10 nm AlGaAs and GaAs layers, have been made using a scanning tunneling microscope. All the layers appear distinct and the dimensions of the as-grown layers can be accurately measured. Furthermore, alloy fluctuations and interface roughness over 2 nm length scales and ordering along certain directions are clearly observed. © 1993.