Scanning force microscopy images of the Si(111)7 x 7 surface reconstruction were presented which were taken in the contact mode in ultra-high vacuum. Topographic and lateral force data were acquired simultaneously. A special treatment of the sensing tip with PTFE helps to overcome the strong adhesion and wear effects that normally occurred on this particular surface.

Scanning Force Microscopy on the Si(111)7 x 7 Surface Reconstruction. L.Howald, R.Lüthi, E.Meyer, P.Güthner, H.J.Güntherodt: Zeitschrift für Physik B, 1994, 93[3], 267-8