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A new methodology is developed for the fabrication of nanostructures on substrate based on anodized Al2O3(AAO) porous template transfer process. It includes (1) forming amorphous alloy, negative UV-resist resin (i.e., SU-8), or PMMA (polymethylmethacrylate) plate nanorod arrays by hot-press molding amorphous alloy, negative UV-resist resin (i.e., SU-8), or PMMA plate into the anodized Al2O3porous substrates; (2) removing AAO templates by chemical etching process after suitable posttreatment (annealing and/or irradiation) to improve the mechanical strength of the nanorod arrays; (3) reforming nanopore films by hot-embossing the nanorod arrays into a thin layer of polymer film on substrates (e.g., silica); (4) cleaning the bottom residues in pores of the films by oxygen plasmon. The results indicate that the diameters of amorphous alloy (or negative UV-resist resin or PMMA) nanorod arrays can be ranged from 32 nm to 200 nm. The diameters of the imprinted ILR-1050 photoresist nanopores are about 94.5 ± 12.2 nm and the diameters of the imprinted or SU-8 resin on glass slides nanopores are about 207 ± 26.4 nm, which inherit the diameters of AAO templates. This methodology provides a general method to fabricate nanorods arrays and/or thin nanopore films by template transfer nanoimprint process.

One-dimension ZnSe and ZnO nanostructures with controlled diameters from 10 to 80 nm and lengths from 30 nm to micrometers were grown via the vapor–liquid–solid growth process using Au nanoparticles as catalysts fabricated by anodic aluminum oxide template assisted vapor deposition. The dependence of the growth on Au nanoparticle (NP) diameters and vapor stoichiometry during growth was investigated. Statistical analysis of the dimensions of nanostructures showed that large Au NPs led to thick and long nanorods (NRs) or nanowires (NWs) within the initial growth phase, but resulted in a slow growth rate as the NRs elongate. The diameter ratio of NRs to Au NPs, or R (Dnanorod/DAu), decreases from 0.45 to 0.32 as the mean length of NRs increases from 30 nm to 230 nm. The composition changes as the NRs elongate, as identified by energy dispersive X-ray analysis, indicate that the stoichiometry of ZnSe NWs can be controlled from Zn-rich to Se-rich; however, for ZnO NRs and NWs, their stoichiometry maintains Zn-rich throughout the growth process. These results are significant for the controlled fabrication of one-dimension nanostructures since their optoelectronic properties are directly determined by their dimensions and composition stoichiometry.

We report on ordered nanoporous films exhibiting a unique magneto-plasmon based response, fabricated by nanosphere-assisted physical deposition. This work focuses on multi-layer Ag/CoFeB/Ag films as examples of such structures. Their microstructure dependent magnetic properties, localized surface plasmon resonance (LSPR) and magneto-optical Kerr effect were investigated. The observed effects of nanopores and Ag layers on the magnetic properties indicate the synergistic interaction between nanopores and Ag layers leading to an enhancement of the ferromagnetic character of the CoFeB film. LSPR spectra reveal that the introduction of Ag layers enhances the light transmission in the nanoporous CoFeB films (having pore sizes exceeding the wavelength of light) due to an enhanced interaction of light with surface plasmons. Periodic nanoporous Ag/CoFeB/Ag films covered by Ag capped nanospheres show a much larger extinction than uncovered nanoporous Ag/CoFeB/Ag films. The correlation between the magneto-optical Kerr effect and the nanostructures suggests a field-tunable Kerr effect owing to the magneto-electric coupling between the magnetic layer and the Ag layers, which is enhanced by the nanopores. These hybrid nanostructures are expected to offer potential applications in photovoltaic cells and for magneto-optic sensors.