Separation of Neighboring Terraces on a Flattened Si(111) Surface by Selective Etching along Step Edges Using Total Wet Chemical Processing

Langmuir. 2022 Mar 29;38(12):3748-3754. doi: 10.1021/acs.langmuir.1c03317. Epub 2022 Mar 17.

Abstract

We propose a bottom-up technique using total wet chemical treatments to separate neighboring terraces on Si(111). First, Ag cations were reduced at the step edges of a vicinal Si(111) surface composed of biatomic steps and flat terraces, resulting in self-assembled Ag rows consisting of nanodots and nanowires. By immersing this sample into a mixed solution of HF and H2O2, almost continuous nanotrenches with depths and widths of nanometer scales were fabricated along the edges. The potential electrochemical processes in the solution/Ag/Si system that lead to the formation of nanotrenches are discussed. Additionally, we present how we plan to use our approach to create atomic-thickness Si ribbons.