• Journal of Information Display
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• 제2권3호
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• pp.78-85
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• 2001

The growth of carbon nanotubes(CNTs) in anodic aluminum oxide(AAO) template and their application to a field emitter are described. AAO templates were fabricated by anodizing bulk aluminum and sputtered thin Al film on Nb-coated Si wafers. After Co catalyst had been electrochemically deposited into the bottom of the pores in AAO template, CNTs were grown by pyrolyzing $C_2H_2$. Depending on the reaction conditions, CNTs grew up to or over the top of the pores in AAO template with different structures. The morphology and structure of CNTs were observed with a scanning electron microscope and a transmission electron microscope. The diameter of CNTs strongly depended on the size of the pores in AAO template and the growing conditions. The electron field emission measurement of the samples resulted in the turn-on field of 1.9-2.2 $V/{\mu}m$ and the field enhancement factor of 2450-5200. The observation of high field enhancement factors is explained in terms of low field screening effect.

• 한국수소및신에너지학회논문집
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• 제17권1호
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• pp.39-46
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• 2006

Highly ordered Li dispersed nickel oxide nanotubes were prepared with anodic aluminum oxide (AAO) template for hydrogen storage. Electron microscope results showed that uniform length and diameter of nickel oxide nanotubes were obtained. The wall thickness and outer diameter of nickel oxide nanotubes are about 40 - 50 nm and 200 - 400 nm, respectively. It was observed that the diameter of nickel oxide nanotubes is bigger than the pore diameter of AAO template. Li dispersed nickel oxide were consisted of nanoflakes and had structures of nanotubes and nanorods. For increasing the hydrogen adsorption and desorption capacity, the Li dispersed nickel oxide nanotubes were fluorinated. The fluorinated Li dispersed nickel oxide nanotubes showed 1.65 wt% of the hydrogen adsorption capacities at 77 K under 47 atm.

• 한국재료학회지
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• 제14권9호
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• pp.664-669
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• 2004

Anodic aluminum oxide (AAO) with pores of various diameter, density, and thickness values was obtained through control of the anodization parameters including voltage, temperature, pore widening time, anodization time, etc. The pore diameter was controlled by a pore widening in an etchant, and alumina templates having stepped nano-channels were fabricated by repetition of anodization and pore widening processes. Stepped carbon nanotubes (CNTs) were then grown on the stepped AAO templates by pyrolysis of acetylene without using the catalyst. High-resolution transmission electron microscopy images revealed that CNTs have a multi-wall structure made of graphite flakes of several nm sizes. The current-voltage characteristic of the sloped and linear CNTs were also examined.

• Journal of Electrical Engineering and Technology
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• 제1권2호
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• pp.246-250
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• 2006

Highly ordered gold nanodot arrays have been successfully obtained by vacuum evaporation using an anodic aluminum oxide (AAO) as a shadow mask. An AAO mask with the thickness of 300 um was prepared through an anodization process. The structure of the nanodot arrays was studied by a field- emission scanning electron microscope (FE-SEM) equipped with an energy dispersive spectrometer (EDS). A tapping mode atomic force microscope (AFM) was employed for studies of height and phase feature. The nanodot arrays were precisely reproduced corresponding to the hexagonal structure of the AAO mask in a large area. In the gold nanodot arrays, the average diameter of dots is approximately the same as the AAO pore size in the range from 70 um to 80 nm and 100 nm center-to-center spacing. EDS analysis indicated that the gold dots were almost entirely consisted of gold, a highly demanded material.

• 제어로봇시스템학회논문지
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• 제14권5호
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• pp.420-425
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• 2008

PMMA light guiding plate with nano-sized pattern was fabricated using anodized aluminum oxide membrane as a template for nano imprint lithography. Nano-sized pore arrays were prepared by the self-organization processes of the anodic oxidation using the aluminum plate with 99.999% purity. Since the aluminum plate has a rough surface, the aluminum plate with thickness of 1mm was anodized after the pre-treatments of chemical polishing, and electrochemical polishing. The surface morphology of the alumina obtained by the first anodization process was controlled by the concentration of electrochemical solution during the first anodization. The surface morphology of the alumina was also changed according to temperature of the solution during chemical polishing performed after first anodization. The pore widening process was employed for obtaining the one-channel with flat surface and height of the channel because the pores of the alumina membrane prepared by the fixed voltage method shows the structure of two-channel with rough surface. It is shown from SPM results that the nano-sized pattern on PMMA light guiding plate fabricated by nano imprint lithography method was well transferred from that of anodized aluminum oxide template.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 춘계학술대회 논문집
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• pp.240-243
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• 2009

Recently, many researches on the development of super-hydrophobic and anti-reflective surfaces have been concentrated on the fabrication of nano-patterned products. The nano-patterned mold is a key to replicate nano-patterned products by mass production techniques such as injection molding and UV molding. The present paper proposes fabricating nano-patterned mold with cost-effective method. The nano-pattern molded was fabricated by electroforming the anodic aluminum oxide template without E-beam lithography. The final mold with nano-patterns showed the pores with the diameter of $100{\sim}120$ nm and the height of 150 nm was fabricated.

• 한국전기전자재료학회논문지
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• 제27권7호
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• pp.448-451
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• 2014

Anodic aluminum oxides (AAO) fabricated by the two-step anodizing process have attracted much attention for the fabrication of nano template because of pore structure with high aspect ratio, low cost process and ease of fabrication. AAOs are characterized by a homogeneous morphology of parallel pores that grow perpendicular to the template surface with a narrow distribution of diameter, length and inter-pores spacing, all of which can be easily controlled by suitably choosing of the anodizing parameters such as pH of the electrolyte, anodizing voltage and duration of anodizing. In this study, AAO templates were characterized by X-ray diffraction and field-emission scanning electron microscope (FE-SEM). The dependence of the pore size change according to the amount of addition of phosphoric acid, which was used to remove the initial alumina oxide layer, was not observed.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2007년도 추계학술대회 논문집
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• pp.166-167
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• 2007

본 연구에서는 Anodic Aluminum Oxide(AAO)-Nano Template 제조 시 알루미늄의 결정방위가 AAO 미세공 형성에 미치는 영향을 연구하였다. 시료는 직경 20mm 두께 2mm의 (200), (220), (111) 세가지 알루미늄 단결정 시편을 사용 하였으며 이는 XRD 장비로 단결정임을 확인 하였다. 양극산화에 앞서 평활한 면을 얻기 위해 다이아몬드 콤파운드($1{\mu}m$)로 미세연마 하였으며 양극산화는 세가지 시편에 대해 모두 동일한 조건에서 2단계 양극산화까지 하였다. 결과는 주사전자현미경(FE-SEM)으로 제조된 AAO 표면의 세공형태와 단면을 모두 관찰 하였으며 그 결과 (200) 결정방위가 (220), (111) 결정 방위보다 세공 형태 균일도 및 단면 정열도와 직진성이 우수함을 관찰 할 수 있었다.

• 한국재료학회지
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• 제13권9호
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• pp.593-597
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• 2003

Anodic aluminum oxide (AAO) membrane was made of aluminum sheet (99.6%, 0.2 mm thickness). The regular array of hexagonal nano pores or channels were prepared by two step anodization process. A detail description of the AAO fabrication is presented. After the 1st anodization in oxalic acid (0.3 M) at 45 V, The formed AAO was removed by etching in a solution of 6 wt% $H_3$$PO_4$＋1.8 wt% $H_2$$CrO_4$. The regular arrangement of the pores was obtained by the 2nd anodization, which was carried out in the same condition as the 1st anodization. Subsequently, the alumina barrier layer at the bottom of the channel layer was removed in phosphoric acid (1M) after removing of aluminum. Pore diameter, density, and thickness could be controlled by the anodization process parameters such as applied voltage, anodizing time, pore widening time, etc. The pore diameter is proportional to the applied voltage and pore widening time. The pore density and thickness can be controlled by anodization temperature and voltage.

• 전기화학회지
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• 제12권1호
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• pp.47-53
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• 2009

본 연구에서는 불순물이 포함된 Al 기판으로부터 두 단계의 양극산화 (anodization) 법에 의해 균일한 나노기공을 갖는 AAO(Anodic Aluminum Oxide)을 제조하였다. 생성된 AAO템플릿 위에 Deposition-Precipitation(DP)방법을 사용하여 수직으로 형성된 $TiO_2$ 나노섬유에 Au를 첨가시켜 2 wt.% $Au/TiO_2$ 나노섬유룰 제조하였다. 두 단계의 양극산화를 통해 규칙적으로 배열된 AAO 기공 형상과 기판 위에 수직으로 배향된 $TiO_2$ 나노섬유의 형상을 SEM을 통해 확인하였다. 또한 $Au/TiO_2$ 나노섬유의 특성은 XRD와 Raman 분석을 통하여 $TiO_2$의 아나타제(anatase)와 루타일(rutile) 결정구조와 $TiO_2$ 나노섬유에 담지된 Au의 존재를 확인하였다. 또한 일산화탄소(CO) 산화반응을 통해 AAO(Anodic Aluminum Oxide)기판 위에 형성된 $TiO_2$와 2 wt% $Au/TiO_2$ 나노섬유의 광촉매적 활성을 비교하였다.