Single-ion induced surface modifications on hydrogen-covered Si(001) surfaces—significant difference between slow highly charged and swift heavy ions

Abstract

Hydrogen-covered Si(001) surfaces were exposed to swift heavy ions (SHI) and slow highly charged ions (HCI). Using scanning tunneling microscopy as analysis tool, the ion-induced modifications on the surface were resolved on the atomic scale. SHI were found occasionally to lead to changes which are restricted to one or two Si surface atoms. In comparison, HCI form pits of several nanometers in diameter, depending on the potential energy of the HCI. These observations are in contrast to many material systems for which similar effects of SHI and HCI have been observed. The results suggest a high stopping power threshold for SHI-induced modifications in crystalline silicon with major implications for the application in silicon-based nanotechnology.

Keywords

• swift heavy ions
• silicon
• highly charged ions
• scanning tunneling microscopy
• STM