An interpretation of the scanning tunnelling microscopic images of clean (001) surfaces was presented. Scanning tunnelling microscopic observations and ab initio simulations of scanning tunnelling microscopic images were performed for buckled dimers at the SA step of clean (001) surfaces. By comparing experimental and theoretical results, it was revealed that the scanning tunnelling microscopic images depended upon the sample bias and the tip-sample separation. This permitted the clarification of the relationship between corrugation in scanning tunnelling microscopic images, and the atomic structure of buckled dimers. In order to elucidate these changes, details of the spatial distributions of the π, π* surface states and the σ, σ* Si-Si bond states in the local density of states (which contributed to scanning tunnelling microscopic images) were analyzed.

Detailed Analysis of Scanning Tunnelling Microscopy Images of the Si(001) Reconstructed Surface with Buckled Dimers. H.Okada, Y.Fujimoto, K.Endo, K.Hirose, Y.Mori: Physical Review B, 2001, 63[19], 195324 (7pp)