• Korean Journal of Materials Research
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• v.12 no.2
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• pp.121-128
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• 2002

Anodic alumina layer can be used as templates for preparation of nano-structured materials, because porous oxide layer on aluminum shows a uniform pore size and a high pore density. In order to find out possibility for template material to prepare nano wire, the effects of the anodic applied potential, anodic time and the temperature of electrolyte on pore diameter of anodic alumina layer were studied using SEM and AFM. The pore diameter of anodic alumina layer increased with applied anodic potential and electrolytic temperature. Especially, the pore diameter of anodic oxide layers formed in chromic acid can be well replicated by widening process in $H_3$$PO_4$solution.

• Korean Journal of Materials Research
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• v.12 no.11
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• pp.856-859
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• 2002

To investigate effects of heat treatments including grain size control in substrate aluminum on nanopore arrays in anodic alumina template, aluminum was heat treated at $500^{\circ}C$ for 1h. The heat treated aluminum was anodized by two successive anodization processes in oxalic solution and the nanopore arrays in anodic alumina layer were studied using TEM and FE-SEM. The highly ordered porous alumina templates with 110 nm interpore distance and 40 nm pore diameter have been observed and the pore array of the anodic alumina has a uniform and closely-packed honeycomb structure. In the case of alumina template obtained from heat treated aluminum substrate, the well- ordered nanopore region in anodic alumina increased and became more homogeneous compared with that from non-heattreated one.

• Journal of the Korean institute of surface engineering
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• v.43 no.5
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• pp.248-254
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• 2010

Porous $Al_2O_3$ film can be utilized as template for fabrication of nano-structured materials. Porous anodic alumina layer as template was prepared by anodization of aluminum in oxalic acid, and the pore diameter and barrier-type alumina layer can be controlled for proper anodizing parameter by widening process in $H_3PO_4$ solution. The $SiO_2$ nanodot and Ni nanowire was fabricated using anodic alumina template and their characteristics were investigated using SEM and TEM with EDS. Especially the growth mechanism of $SiO_2$ nanodot in alumina membrane compared with thinning of the alumina barrier layer during anodization was also investigated.

• Korean Journal of Materials Research
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• v.12 no.1
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• pp.89-93
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• 2002

To investigate the effect of properties of pores in anodic alumina template(AAT) on the formation and characteristics of metal nano wires, Cu and Ni nano wires were manufactured using anodic alumina template formed in various electrolytes. The characteristics of prepared metal nano wires using AAT could be replicated from those of pores in AAT. The diameters of nano wires could be controlled by the widening process of anodic porous film in $H_3PO_4$ solution. The shape ratio of the nano wire was shown to be $170{\pm}30$ for Ni nano wire formed by AAT made in sulfuric acid.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.375-375
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• 2007

In the conventional crystallization method, thepoly-Si TFTs show poor device-to-device uniformity because of the random location of the grain boundaries. However, our new crystallization method introduced in this paper employed substrate-embedded seeds on the highly ordered anodic alumina template to control both the location of seeds and the number of grain boundaries intentionally. In the process of excimer laser crystallization (ELC), a-Si film deposited on the anodic alumina by low pressure chemical vapor deposition (LPCVD) is transformed into fine poly-Si grains by explosive crystallization (XC) prior to primary melting. At the higher energy density, the film is nearly completely melted and laterally grown by super lateral growth (SLG) from remained small part of the fine poly-Si grains as seeds at the Si/anodic alumina interface. Resultant grain boundaries have almost linear functions of the number of seeds in concavities of anodic alumina which have a constant spacing. It reveals the uniformity of. device can be enhanced prominently by controlling location and size of pores which contains fine poly~Si seeds under artificial anodizing condition.

• Journal of Powder Materials
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• v.19 no.5
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• pp.367-372
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• 2012

Single crystalline Cu nanowires with controlled diameters and aspect ratios have been synthesized using electrochemical deposition within confined nanochannels of a porous anodic aluminium oxide(AAO) template. The diameters of nano-sized cylindrical pores in AAO template were adjusted by controlling the anodization conditions. Cu nanowires with diameters of approximately 38, 99, 274 nm were synthesized by the electrodeposition using the AAO templates. The crystal structure, morphology and microstructure of the Cu nanowires were systematically investigated using XRD, FE-SEM, TEM and SAED. Investigation results revealed that the Cu nanowires had the controlled diameter, high aspect ratio and single crystalline nature.

• Bulletin of the Korean Chemical Society
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• v.27 no.8
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• pp.1159-1163
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• 2006

Aluminum nanotube has been fabricated by a physical vapor deposition/atmospheric pressure injection using an anodic porous alumina film as a template. The pore external-, and inside diameters and the length of the aluminum nanotubes fabricated by this method are 60 nm, 35 nm and 2 $\mu$m, respectively. The structure of the fabricated aluminum nanotubes was examined by a kind of chemical treatment as extraction of copper on the cross-sectional area of these aluminum tubes in a mixed solution of $CuCl_2$ and HCl by difference of ionization tendency between aluminum and copper. The composition of the aluminum nanotube was identified by the two dimensional Hybrid Plasma Equipment Model (HPEM) employing the inductively coupled plasma.

• Journal of the Korean Vacuum Society
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• v.15 no.5
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• pp.518-526
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• 2006

Nanoporous alumina film was fabricated by anodization of an aluminum sheet. Highly ordered nanowellstructured and nanonets-tructured metal films were fabricated by vacuum evaporation of several metals(Al, Sn, and Co) using the anodic nanoporous alumina film as a template. In this experiment, an anodic porous alumina film with the cell size of 100 nm and the pore diameter of 60 nm was used. The resistance heating method was adopted for evaporating a desired metal, and vapor deposition was carried out under the base pressure of torr. It was founded that whether the structure fabricated by vacuum evaporation is nanowell or nanonet is dependent on the amount of deposited material. When an anodic porous alumina film with the cell size of 100 nm and the pore diameter of 60 nm was used, a nanowell-structured film was fabricated when a sufficient amount of metal was suppled to cover the surface pores. On the other hand, nanonet-structured film was fabricated bellow a half the amount of metal required for nanowell-structured film.

• Proceedings of the Materials Research Society of Korea Conference
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• 2006.11a
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• pp.16.2-16.2
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• 2006

• Journal of the Korean Society for Heat Treatment
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• v.22 no.1
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• pp.23-26
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• 2009

Pt nanotubes with diameter of 200 nm were fabricated by simple and convenient method of Template-Wetting Process. Porous alumina membranes were prepared by 2 step anodic oxidation as the template. To improve wetting properties and lower surface energy, pt solution was mixed with polymer. Polymer was removed completely during annealing. Grain growth process of pt nanotubes during baking and furnace annealing was examined by FE-SEM and XRD.