The defect structures in HgTe/CdTe superlattices on CdTe/Si(211)B substrates grown by means of molecular-beam epitaxy were investigated by using (scanning) transmission electron microscopy and electron energy loss spectroscopy. Straight Hg-rich defects perpendicular to the superlattices were observed near to the substrate while Frank dislocation loops were seen far from the substrate. The Hg-rich defects exhibited only a compositional variation, with no significant atomic shift, and could be considered to be remnants of a Frank dislocation loop which had climbed by thermal diffusion during growth.

Frank Dislocation Loops in HgTe/CdTe Superlattices on CdTe/Si(211)B Substrates. L.F.Fu, N.L.Okamoto, M.F.Chi, N.D.Browning, H.S.Jung, C.H.Grein: Journal of Applied Physics, 2008, 104[2], 023104