Preparation of atomically clean and flat Si(100) surfaces by low-energy ion sputtering and low-temperature annealing

TL;DR

This study demonstrates that combining wet-chemical etching, low-energy Ar ion sputtering, and high-temperature annealing produces atomically clean and flat Si(100) surfaces, essential for nanoscale device fabrication.

Contribution

It introduces a method using low-energy ion sputtering and high-temperature annealing to achieve atomically clean Si(100) surfaces, improving surface preparation techniques.

Findings

Wet-chemical etching alone is insufficient for clean surfaces.

Room temperature sputtering followed by annealing yields atomically flat surfaces.

Surfaces prepared are suitable for nanoscale device fabrication.

Abstract

Si(100) surfaces were prepared by wet-chemical etching followed by 0.3-1.5keV Ar ion sputtering, either at elevated or room temperature. After a brief anneal under ultrahigh vacuum conditions, the resulting surfaces were examined by scanning tunneling microscopy. We find that wet-chemical etching alone cannot produce a clean and flat Si(100) surface. However, subsequent 300eV Ar ion sputtering at room temperature followed by a 973K anneal yields atomically clean and flat Si(100) surfaces suitable for nanoscale device fabrication.