Scanning Tunneling Microscope Fabrication of Atomic-Scale Memory on a Silicon Surface

Abstract
By using a scanning tunneling microscope (STM) operated in an ultrahigh vacuum, we can extract single Si atoms from predetermined positions of the Si(111)-7×7 surface through field evaporation. This technique enables us to create specific arrangements of Si vacancies on the surface. Some of the extracted Si atoms can be captured by the tip and redeposited onto the surface. We show that natural Si vacancy defects existing on the surface can be repaired by this technique. These results demonstrate the potential of STM for the construction of atomic-scale data memory.