Article ID Journal Published Year Pages File Type
1675489 Thin Solid Films 2006 5 Pages PDF
Abstract

Regular arrays of Ta nanopillars, 200 nm wide and 500 nm tall, were grown on SiO2 nanosphere patterns by glancing angle sputter deposition (GLAD). Plan-view and cross-sectional scanning electron microscopy analyses show dramatic changes in the structure and morphology of individual nanopillars as a function of growth temperature Ts ranging from 200 to 700 °C. At low temperatures, Ts ≤ 300 °C, single nanopillars develop on each sphere and branch into subpillars near the pillar top. In contrast, Ts ≥ 500 °C leads to branching during the nucleation stage at the pillar bottom. The top branching at low Ts is associated with surface mounds on a growing pillar that, due to atomic shadowing, develop into separated subpillars. At high Ts, the branching occurs during the nucleation stage where multiple nuclei on a single SiO2 sphere develop into subpillars during a competitive growth mode which, in turn, leads to intercolumnar competition and the extinction of some nanopillars.

Related Topics
Physical Sciences and Engineering Materials Science Nanotechnology
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