Peculiar three-dimensional ordering in ( In , Ga ) As / GaAs ( 311 ) B quantumdot superlattices

The impact of the GaAs spacer layer thickness on the three-dimensional ordering in ( In , Ga ) As / GaAs ( 311 ) B quantum dot superlattices was investigated by high-resolution x-ray diffraction, cross-sectional transmission electron microscopy, and atomic force microscopy. Dramatic changes in both planar and vertical ordering could be observed. A distinct correlation was found in that the azimuthal angle of inclined vertical inheritance of the dot positions is perpendicular to the planar direction between the dot chains within individual quantum dot layers. These directions are close to [130] or [ 1 ¯ 03 ] .