Kink-induced buckled dimers on Si(001) and Ge(001) at room temperature studied by scanning tunneling microscopy

The structure of kinks at monatomic steps on Si(001) and Ge(001) is investigated by high-resolution scanning tunneling microscopy at room temperature. In addition to previously known asymmetric-dimers at edges of the ${\mathit{S}}_{\mathit{A}}$ and ${\mathit{S}}_{\mathit{B}}$ steps running parallel and perpendicular to dimer rows in the upper terrace, respectively, we have found that kinks at both ${\mathit{S}}_{\mathit{A}}$ and ${\mathit{S}}_{\mathit{B}}$ steps induce buckled (asymmetric-appearing) dimers locally in the connecting dimer rows in the lower terrace. Influence of the kinks on the formation of a c(4×2) phase of asymmetric dimers at low temperatures is discussed. © 1996 The American Physical Society.