Fabrication of Highly Ordered Polymeric Nanodot and Nanowire Arrays Templated by Supramolecular Assembly Block Copolymer Nanoporous Thin Films

Abstract

Realizing the vast technological potential of patternable block copolymers requires both the precise controlling of the orientation and long-range ordering, which is still a challenging topic so far. Recently, we have demonstrated that ordered nanoporous thin film can be fabricated from a simple supramolecular assembly approach. Here we will extend this approach and provide a general route to fabricate large areas of highly ordered polymeric nanodot and nanowire arrays. We revealed that under a mixture solvent annealing atmosphere, a near-defect-free nanoporous thin film over large areas can be achieved. Under the direction of interpolymer hydrogen bonding and capillary action of nanopores, this ordered porous nanotemplate can be properly filled with phenolic resin precursor, followed by curation and pyrolysis at middle temperature to remove the nanotemplate, a perfect ordered polymer nanodot arrays replication was obtained. The orientation of the supramolecular assembly thin films can be readily re-aligned parallel to the substrate upon exposure to chloroform vapor, so this facile nanotemplate replica method can be further extend to generate large areas of polymeric nanowire arrays. Thus, we achieved a successful sub-30 nm patterns nanotemplates transfer methodology for fabricating polymeric nanopattern arrays with highly ordered structure and tunable morphologies.

Figure 1

Scheme of the fabrication of highly ordered polymeric nanodot and nanowire arrays templated by nanoporous thin films

Figure 2

AFM images of nanoporous thin filmsaheight image,bphase image. Mixture solvent annealing for 24 h, and washed with methanol. Thin film 45 nm thick, lateral scale 1500 nm × 1500 nm. The inset is the FFT plot of the image

Figure 3

AFM images of the nanoporous thin filmsaheight image,bphase image,cenlarged height image. Mixture solvent annealing 72 h, and washed with methanol. Thin film 45 nm thick, lateral scale 1500 nm × 1500 nm. The inset is the FFT plot of the AFM image

Figure 4

AFM images of highly ordered polymeric nanodots arrays from nanoporous thin film after pyrolysis.aHeight image,bPhase image. Lateral scale 1500 nm × 1500 nm.cEnlarged height image

Figure 5

aAFM height images of thin film nanotemplate, after re-alignment using chloroform annealing for 15 min.bHeight images of the resulted short polymeric nanowire arrays replica after pyrolysis. Lateral scale 2000 nm × 2000 nm

Figure 6

aAFM height images of thin film nanotemplate, after re-alignment using chloroform annealing for 30 min.bAFM height images of polymeric nanowire arrays replica after pyrolysis. Lateral scale 2000 nm × 2000 nm