  A clean Si(001) surface thermally purified in an ultrahigh vacuum
molecular-beam epitaxy chamber has been investigated by means of scanning
tunneling microscopy. The morphological peculiarities of the Si(001) surface
have been explored in detail. The classification of the surface structure
elements has been carried out, the dimensions of the elements have been
measured, and the relative heights of the surface relief have been determined.
A reconstruction of the Si(001) surface prepared in the molecular-beam epitaxy
chamber has been found to be (8 x n). A model of the Si(001)-(8 x n) surface
structure is proposed.

Materials Science;Mesoscale and Nanoscale Physics