Producing nanodot arrays with improved hexagonal order by patterning surfaces before ion sputtering
arXiv:1511.01547 · doi:10.1103/PhysRevE.92.062401
Abstract
When the surface of a nominally flat binary material is bombarded with a broad, normally-incident ion beam, disordered hexagonal arrays of nanodots can form. Shipman and Bradley have derived equations of motion that govern the coupled dynamics of the height and composition of such a surface [P. D. Shipman and R. M. Bradley, Phys. Rev. B 84, 085420 (2011)]. We investigate the influence of initial conditions on the hexagonal order yielded by integration of those equations of motion. The initial conditions studied are hexagonal and sinusoidal templates, straight scratches and nominally flat surfaces. Our simulations indicate that both kinds of template lead to marked improvements in the hexagonal order if the initial wavelength is approximately equal to or double the linearly selected wavelength. Scratches enhance the hexagonal order in their vicinity if their width is close to or less than the linearly selected wavelength. Our results suggest that prepatterning a binary material can dramatically increase the hexagonal order achieved at large ion fluences.
arXiv comment23 pages, 16 captioned figures
References in corpus (7)
- On the stabilization of ion sputtered surfaces
- Is keV ion induced pattern formation on Si(001) caused by metal impurities?
- Ion induced solid flow
- Hydrodynamic approach to surface pattern formation by ion beams
- Solid flow drives surface nanopatterning by ion-beam irradiation
- Nanopatterning of Si surfaces by normal incident ion erosion: influence of metal incorporation on surface morphology evolution
- One-dimensional pattern of Au nanodots by ion-beam-sputtering: formation and mechanism