Using scanning tunnelling microscopy, an investigation was made of the vacancy-mediated layer-by-layer removal of surface atoms from Si(111) under 225eV Xe-ion bombardment. Observed, with increasing substrate temperature, were both a transition from vacancy-cluster nucleation to step retraction and a transition from disruption to preservation of the 7 x 7 reconstruction on exposed material.

Surface Reconstruction in Layer-by-Layer Sputtering of Si(111). P.Bedrossian, T.Klitsner: Physical Review B, 1991, 44, 13783-6