Si(1 0 0) surfaces were prepared by wet-chemical etching followed by 0.3-1.5 keV Ar ion sputtering, either at elevated or room temperature (RT). After a brief anneal under ultrahigh vacuum (UHV) conditions, the resulting surfaces were examined by scanning tunneling microscopy. We find that wet-chemical etching alone cannot produce a clean and flat Si(I 0 0) surface. However, subsequent 300 eV At ion sputtering at room temperature followed by a 700 degreesC anneal yields atomically clean and flat Si(I 0 0) surfaces suitable for nanoscale device fabrication. (C) 2003 Elsevier B.V. All rights reserved.