Using the spectroscopic capabilities of a scanning tunneling microscope, we identified and investigated a low-temperature reconstruction pathway for forming Si(111)($\sqrt{3}$×$\sqrt{3}$)R30°-Ag from the Si(111)3×1-Ag interface. A metastable intermediate phase consisting of one-dimensional atom chains atop the Si(111)3×1-Ag reconstruction stabilizes locally. The density of states at the chains indicates a Ag-Si bonding configuration similar to that of the ($\sqrt{3}$×$\sqrt{3}$)R30° reconstruction. We propose a mechanism for the (3×1) to ($\sqrt{3}$×$\sqrt{3}$)R30° phase transformation at low temperature. © 1996 The American Physical Society.

• Received 8 February 1996

DOI:https://doi.org/10.1103/PhysRevB.53.12651