AN STM STUDY OF MECHANOCHEMICALLY PREPARED SI(111) SUBSTRATES - AN EXTENDED SET OF VICINAL SURFACES

The morphology and surface structure of mechanochemically treated Si(111) samples, originally prepared for transmission electron microscopy studies, have been determined by scannning tunneling microscopy (STM). During the preparation method, the Si(111) planes are cut under continuously changing polar angles in all azimuthal directions. The result is a dimple whose concave surface breaks up, under UHV heat treatment, into a large number of vicinal (111) surfaces. STM measurements, performed on different parts of the dimple, show the facetting of this surfaces into (111)-oriented, 7 x 7 reconstructed terraces, steps and step bunches. Characteristic features observed by STM on this type of vicinal substrate correspond to results reported on individually prepared vicinal surfaces.