title: Ordered arrays of nanoporous silicon nanopillars and silicon nanopillars with nanoporous shells.
abstract: The fabrication of ordered arrays of nanoporous Si nanopillars with and without nanoporous base and ordered arrays of Si nanopillars with nanoporous shells are presented. The fabrication route is using a combination of substrate conformal imprint lithography and metal-assisted chemical etching. The metal-assisted chemical etching is performed in solutions with different [HF]/[H2O2 + HF] ratios. Both pore formation and polishing (marked by the vertical etching of the nanopillars) are observed in highly doped and lightly doped Si during metal-assisted chemical etching. Pore formation is more active in the highly doped Si, while the transition from polishing to pore formation is more obvious in the lightly doped Si. The etching rate is clearly higher in the highly doped Si. Oxidation occurs on the sidewalls of the pillars by etching in solutions with small [HF]/[H2O2 + HF] ratios, leading to thinning, bending, and bonding of pillars.
authors: Materials for Electronics, Institute of Materials Engineering and Institute of Micro- and Nanotechnologies MacroNano®, Ilmenau University of Technology, Gustav-Kirchhoff-Str, 5, Ilmenau, 98693, Germany. dong.wang@tu-ilmenau.de.
authors: Dong
authors: D
authors: Wang
authors: Ran
authors: R
authors: Ji
authors: Song
authors: S
authors: Du
authors: Arne
authors: A
authors: Albrecht
authors: Peter
authors: P
authors: Schaaf