D.c. Current-Dependent Faceting of Vicinal Si(111)

Abstract

We have studied the step structure of a vicinal Si(111) surface heated by a d.c. current between 1100 K and 1570 K in a synchrotron X-ray scattering experiment. Above 1275 K, a reversible faceting transformation is observed by switching current direction. On faceting the surface transforms from uniform well-ordered steps to extended (111) facets together with extremely disordered step regions. The current direction for which uniform and well-ordered steps are stable reverses above 1500 K.