Evidence of spontaneous formation of steps on silicon (100)

Abstract

Extra steps have been found with atomic-force microscopy generated on rather flat silicon (100) surfaces annealed at 1200 \ifmmode^\circ\else\textdegree\fi{}C in hydrogen, through a comparison with the surface annealed in argon, which exhibits a typical (${S}_{a}+{S}_{b}$) step structure. It is suggested that the extra steps are spontaneously generated due to the relaxation of the strain energy associated with the atomic dimers on the reconstructed surface.