This article proposes an enhanced oxidation model for scanning probe microscope (SPM) nanolithography that reproduces the power-of-time law reported for tip-induced anodic oxidation. It is shown that the space charge resulting from nonstoichiometric states strongly limits the oxidation rate. The direct relationship between the oxide thickness and time is provided by integration of the oxide rate equation. Measurements on SPM-induced oxides generated on a titanium surface are compared to theory. The predominant role of the space charge is corroborated by electrical measurements on oxide barriers that exhibit current fluctuations due to Coulombic effects.

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Ferromagnetic films evaporated at oblique incidence show invariably an uniaxial in-plane magnetic anisotropy component with easy axis perpendicular to the incidence plane. Scanning Tunneling Microscopy (STM) images reveal that oblique deposition results in rough films with highly anisotropic correlation functions of the surface profile. We show that simple shape anisotropy calculations using high-quality STM roughness data as input reproduce the measured anisotropies remarkably well and unambiguously relate them to the long-ranged dipolar interactions.