The lateral In2O3 nanowires and pyramid networks manipulation by controlled substrate surface energy in annealing evolution

• The lateral aligned In2O3 nanowires and pyramids networks were grown under annealing.
• The successive growth was materialized by the critical self-nucleated condensation.
• Surface energy control was led to nanowires 50 nm in width and pyramids 400 nm in size.
• The growth mechanism of the self-assembled nanocrystals was vapor–solid mechanism.
• The growth process was attributed to the surface diffusion, kinetics and morphology.

The continuous laterally aligned growth of In2O3 nanocrystal networks extended with nanowire and pyramid connections under annealing influence has been reported. These nanostructures have been grown on Si substrate by using oxygen-assisted annealing process through PVD growth technique. The formation of In2O3 nanocrystals has been achieved by the successive growth of critical self-nucleated condensation in three orientations. The preferred direction was the route between two pyramids especially in the smallest surface energy. The effects of substrate temperature in annealing process on the morphological properties of the as-grown nanostructures were investigated. The annealing technique showed that by controlling the surface energy, the morphology of structures was changed from unregulated array to defined nanostructures; especially nanowires 50 nm in width. The obtained nanostructures also were investigated by the (transmission electron microscopy) TEM, Raman spectrum and the (X-ray diffraction) XRD patterns. They indicated that the self-assembled In2O3 nanocrystal networks have been fabricated by the vapor–solid (VS) growth mechanism. The growth mechanism process was prompted to attribute the relationship among the kinetics parameters, surface diffusion and morphology of nanostructures.