A study of the anodic dissolution of polycrystalline aluminum utilizing in-situ Atomic Force Microscopy (MM) is reported. Using a novel snodic dissolution treatment, square terraced pyramids (or “ziggurats”) of constant width are formed on the surface. AFM contour and profile plots reveal the extremely square and flat surfhces of the plateaus on top of the ziggurats, all of them having nearly the same size. This treatment on an Al sample is also shown to yield a substantial improvement in its passivation and corrosion properties. The improved passivation obtained through this method is comparable to that obtained by ion-implantation of passivating metals studied by other authors. This improvement is believed to result from a change in the oxide/metal charge distribution, as a consequence of the band bending in the oxide overlayer.