Atomic-scale modifications of the GaAs(111)B surface were created by applying voltage pulses, between the tip of a scanning tunnelling microscope and the sample, under ultra-high vacuum conditions. A 25ms voltage pulse of 5V (sample negative) resulted in the creation of a disordered region (some 3nm x 3nm in area) of As trimers. In addition, surface stacking faults formed which extended over distances of the order of 10nm and terminated on surface defects. A pulse which had the same parameters, but was of opposite polarity, created a nm-scale crater.

P.Moriarty, P.H.Beton, D.A.Woolf: Applied Physics Letters, 1995, 66[12], 1515-7