Self-assembled nanoholes by molecular beam epitaxial growth and atomically precise in situ etching

Manipulation of nanostructure based on quantum dot (QD) is feasible by applying in situ etching technique. We report a systematic investigation of an in situ etching procedure of capped InAs QD. The AsBr/sub 3/ in situ etching gas produces nanoholes in the GaAs capping layer due to the strain enhanced etching rate on the top of QD. These hole structures can be filled with InAs again to produce lateral QD molecules in the second layer.