Property Change of Si(111) Surface by Scanning Tunneling Microscope Manipulation

Abstract

Scanning tunneling microscopy (STM) has been used to form trench lines 0.2–0.6-nm deep and 10-nm wide by applying a high voltage and/or a large tunneling current between the tip and the Si(111)-7×7 surface. We have found that the apparent height of the surface area surrounded by a complete square trench is 0.1–0.3 nm lower than the outside, while no apparent height difference is measured in the case of a square trench with one open corner. We have also observed that the trench formation is hindered or made difficult inside the complete surface square trench, while the effect is negligible in the case of the open trench.