Effect of structural defects on InSb/Al xIn 1− x Sb quantum wells grown on GaAs [formula omitted] substrates

• Published in: Physica. E, Low-dimensional systems & nanostructures Vol. 20; no. 3; pp. 260 - 263
• Main Authors: Mishima, T.D, Keay, J.C, Goel, N, Ball, M.A, Chung, S.J, Johnson, M.B, Santos, M.B
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 2004
• Subjects: Electron mobility; InSb quantum wells; Structural defects; Transmission electron microscopy; 61.16Bg; 73.61.−r; Transmission electron microscopy; Structural defects; InSb quantum wells; Electron mobility; 61.72.Ff
• ISSN: 1386-9477; 1873-1759
• DOI: 10.1016/j.physe.2003.08.014

We investigate oriented abrupt steps (OASs), a type of surface defect in InSb/Al x In 1− x Sb quantum-well (QW) samples grown on GaAs (0 0 1) substrates. Previous atomic force microscopy studies have reported that the OASs are oriented along the [1 1 0] and [ 1 ̄ 1 0] directions and have an inclination angle of ∼5°–15° with respect to the sample surface. Our plan-view and cross-sectional transmission electron microscopy analyses reveal that the OASs are the terminal edges of threading micro-twins at the sample surface. Hall effect measurements indicate that the density of OASs correlates with the electron mobility in the InSb QWs.