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Modulation of oxide properties in a direction perpendicular to surfaces can be easily achieved by advanced thin film deposition tools. In contrast, simultaneous nanoscale modulation of properties in directions perpendicular and parallel to surfaces, as required for building three-dimensional (3D) nanometric devices, has remained elusive. Though bottom-up approaches allow obtaining controlled lateral growth, these techniques fail to achieve long-range order or do not allow simultaneous modulation of properties in the perpendicular direction. Here, we show that, by exploiting a dual strategy based on the spontaneous surface restructuration of some perovskite substrates and the layer-by-layer growth of nanometric heteroepitaxial perovskite layers, surfaces with laterally modulated surface relief, chemical termination, electrostatic potential, and electrical conductance can be obtained. As illustrative examples, conducting ferromagnetic manganite La2/3Sr1/3MnO3 and ferroelectric BaTiO3 ultrathin films have been grown on (001)SrTiO3 and (001)(La0.18Sr0.82)(Al0.59Ta0.41)O3 substrates with self-ordered chemical terminations.

Exploiting the capability of preparing nanostructured bifunctional terminated SrTiO(3) substrates (SrO and TiO(2)), the surface properties have been locally tuned by employing a double bottom-up strategy which combines the use of chemically nanopatterned substrates with molecular self-assembly. The dynamics of surface diffusion that allows SrO and TiO(2) chemical-termination nano-patterning of the SrTiO(3) is first addressed. Second, termination-dependent heterogeneous nucleation is used to demonstrate that stearic acid selectively grows on the TiO(2) terminated terraces. This adsorption improves the frictional properties and modifies the surface contact potential. The possibility of simultaneously tailoring at the nanoscale different surface properties of widely employed oxide substrates is promising for building up new devices useful for emerging applications.

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We show that the surface of (001)-oriented La0.18Sr0.82Al0.59Ta0.41O3 (LSAT) single-crystalline substrates can be self-ordered as to become a laterally long-range ordered pattern of nanometric stripes of distinct composition. Atomically flat and periodically modulated, the resulting surface exhibits concomitant interface energy variations with an upper growing epilayer. By exploiting combined selective growth and epitaxial strain, these nanostructured substrates are used as templates to promote the self-formation of one-dimensional arrays of SrRuO3 dots.