Zone specificity in low energy electron stimulated desorption of Cl+ from reconstructed Si(111)-7x7:Cl surfaces

Diffraction in electron stimulated desorption has revealed a propensity for Cl+ desorption from rest atom vs. adatom areas and unfaulted vs. faulted zones of Cl-terminated Si(1 1 1)-(7 x 7) surfaces. We associate the 15 eV +/- eV threshold with ionization of Si-Cl sigma-bonding surface states and formation of screened two-hole states with Si 3s character. Similar specificity is observed from A and B reconstructions. This can be due to reduced screening in unfaulted regions and increased hole localization in Si back-bonds within faulted regions. (c) 2006 Elsevier B.V. All rights reserved.