We report on the modification of hydrogen passivated silicon(100) surface by STM in a low voltage mode (Vs= -0.7 - -2.0 volt, I set=1.0 nA) in air. We observed that the scanned area can be oxidized in a low voltage mode and the depth profiles of oxide squares are not same for scanning direction (x-direction) and non-scanning direction (y-direction). The depth profile of x-direction changed gradually at edge region whereas the depth profile of y-direction changed abruptly at edge region. The different depth profiles of oxide squares could be explained by non-uniform concentration of hydrogen atoms at edge region due to the movement of tip. It was also suggested that the oxide formation was enhanced by strong electric field strength between tip and sample rather than bias voltage itself allowing the water and oxygen ions to further attack silicon atoms to result in the formation of oxide bridge between two silicon atoms.
|Journal of the Korean Physical Society
|SUPPL. PART 1
|Published - 1997
ASJC Scopus subject areas
- General Physics and Astronomy