Interface roughness and asymmetry in InAs/GaSb superlattices studied by scanning tunneling microscopy

R. M. Feenstra; D. A. Collins; D. Z. -Y. Ting; M. W. Wang; T. C. McGill

doi:10.1103/PhysRevLett.72.2749

Interface roughness and asymmetry in InAs/GaSb superlattices studied by scanning tunneling microscopy

R. M. Feenstra, D. A. Collins, D. Z. -Y. Ting, M. W. Wang, and T. C. McGill

Phys. Rev. Lett. 72, 2749 – Published 25 April 1994

Abstract

InAs/GaSb superlattices are studied in cross section by scanning tunneling microscopy and spectroscopy. Electron subbands in 42 Å thick InAs layers are clearly resolved in the spectra. Roughness of the superlattice interfaces is quantitatively measured. Interfaces of InAs grown on GaSb are found to be rougher, with different electronic properties, than those of GaSb on InAs, indicating some intermixing in the former case.