Nanometer scale oxidation of silicon surfaces by STM and AFM is an important subject in the SPM community, and its application for nanofabrication has been demonstrated by several groups.Most published work show that the surface can only be oxidized if a positive sample voltage is applied to the sample with respect to the tip (anodization). In the present work we have studied the oxidation mechanism at negative sample voltage with STM and AFM in air and with an electrochemical STM in HF solution. It is demonstrated that two oxidation mechanisms exist, and that the frontier between both oxidation mechanisms is the voltage at which the surface is in the flat band condition. The influence of the electrical field is evaluated and a mechanism for the cathodic oxidation is proposed. © 1998 Springer-Verlag.
|Journal||Applied Physics A: Materials Science and Processing|
|Issue number||SUPPL. 1|
|Publication status||Published - 1 Dec 1998|