Real-space identification of the CZT(110) surface atomic structure by scanning tunneling microscopy

Various sputter–anneal treatments in-vacuum were applied to cleaved Cd0.9Zn0.1Te(110) surfaces. The morphology, stoichiometry, orientation and the atomic structures were investigated on ‘‘as-cleaved” as well as on sputter–annealed surfaces. The studies were conducted by in-situ scanning probe microscopy, in scanning tunneling and atomic force modes, lowand reflection high-energy electron diffraction, and Auger electron spectroscopy. Additional ex-situ investigation methods, such as electron back scattered diffraction and energy dispersive spectroscopy in a scanning electron microscope were applied. Such treatments resulted in a clean, unreconstructed (1 ! 1) surface, which was structurally ordered, even if somewhat rough on the atomic scale. The optimal treatment found in this work consists of several cycles of 1.0 keV sputtering followed by 2 h annealing at 180 !C, despite some compositional changes, most notably Cd enrichment at the surface. The morphology of the surface was shown to depend on the sputtering energy, unlike the (1 ! 1) atomic structure. " 2007 Elsevier B.V. All rights reserved.