SCANNING-TUNNELING-MICROSCOPY INVESTIGATIONS OF CORROSIVE PROCESSES ON SI(111) SURFACES

Corrosive processes on Si(111) surfaces were systematically studied by scanning tunneling microscopy (STM). These include wet chemical etching of oxide covered Si surfaces in NH4F/HF solutions of varying acidity, the growth of thin oxide layers at room temperatures and atmospheric pressures, both on the (7x7) reconstructed and on the (1x1) hydrogen terminated surface, and corrosive reactions with hydrogen and oxygen, which were studied over a wide temperature range. Detailed results on the atomic scale mechanisms of these processes were derived from STM images resolving atomic structures on the processed surfaces.