Local anodic oxidation of silicon using Atomic Force Microscopy (AFM) was investigated by applying a negative voltage between conductive (Au coated silicon or silicon nitride) or non-conductive (silicon nitride) tips and Si surfaces. All samples were cleaned with an ammonium-based solution known in literature as standard cleaning 1 (SC1) or a dip in a diluted hydrofluoric acid solution followed by SC1 cleaning step. Localized squares patterns of oxide, 0.25 ?m2 in area, were formed by growing parallel lines with constant interlinear spacing and length after scanning several times in the same area. From AFM analysis with non-biased tip, it was obtained 3D and section profiles. Simulations were performed in order to model voltage and electric field distributions of the system tip-air-silicon or tip-air-oxide-silicon. In addition, it was simulated the effect of tip termination, circular or sharpen, considering electric field and voltage distributions. Finally, anodic oxidation using non-conductive silicon nitride tip or conductive tips were performed and compared.
