We have used scanning tunneling microscopy to study the faceting of <010> oriented steps on Si(001) and Ge(001) surfaces. The <010> oriented steps on Si(001) tend to facet into local SA and SB step segments, whereas <010> oriented steps on Ge(001) meander along the mean <010> direction. We show that the step faceting behavior of the Si and Ge(001) surfaces is fully governed by the next-nearest-neighbor (NNN) interaction between the substrate dimers. Only in the case of a repulsive NNN interaction, as for Si(001), faceting occurs.
|Number of pages||4|
|Journal||Physical review B: Condensed matter and materials physics|
|Publication status||Published - 2004|