• 한국표면공학회:학술대회논문집
• /
• 한국표면공학회 2016년도 추계학술대회 논문집
• /
• pp.115.2-115.2
• /
• 2016

Al alloys are being used widely for automobile, aerospace and mechanical components because of their high strength ratio to weight. However, still they suffer from abrasion or corrosion owing to insufficient resistances to friction or mechanical impact and chemical attack. Plasma electrolytic oxidation (PEO) method is one of the promising surface treatment methods for Al alloys which can render better hardness than aluminum anodic oxide (AAO) films prepared by conventional anodizing method in acidic solutions. In this presentation, some basic nature of PEO film formation and growth process on Al alloys will be presented based on the experimental results obtained and discussed in view of dielectric breakdown and reformation and the role of various anions in film breakdown and reformation of PEO films.

• 한국전기전자재료학회논문지
• /
• 제16권9호
• /
• pp.801-806
• /
• 2003

In recent years, there has been large interest in the fabrication of the self organized nanoscale structures since not only their potential utilization in electronic, optoelectronic, and magnetic devices but also their fundamental interest such as uniformity and regularization. An attractive candidate of these materials is anodic porous alumina film(Al$_2$O$_3$) which is formed by the anodization of aluminum in an appropriate acid solution. In this study to fabricate the porous alumina film with very uniform and nearly parallel pores the anodization was carried out under constant voltage mode in 0.3M oxalic acid as an electrolyte. The hexagonally ordered arrays with a few $\mu\textrm{m}$ in size two-dimensional polycrystalline structure were obtained of which pore densities were 1.1${\times}$10$\^$10//$\textrm{cm}^2$.

• 반도체디스플레이기술학회지
• /
• 제1권1호
• /
• pp.9-13
• /
• 2002

A polyimide-type electrostatic chuck (ESC) was fabricated for the application of holding 8-inch silicon wafers in the oxide etching equipment. For the fabrication of the unipolar ESC, core technologies such as coating of polyimide films and anodizing treatment of aluminum surface were developed. The polyimide films were prepared on top of thin coated copper substrates for the good electrical contacts, and the helium gas cooling technique was used for the temperature uniformity of the silicon wafers. The ESC was essentially working with an unipolar operation, which was easier to fabricate and operate compared to a bipolar operation. The chucking force of the ESC has been measured to be about 580 gf when the applied voltage was 1.5 kV, which was considered to be enough force to hold wafers during the dry etching processing. The employment of the ESC in etcher system could make 8% enhancement of the wafer processing yield.

• KSBB Journal
• /
• 제27권1호
• /
• pp.45-50
• /
• 2012

In this paper, we investigated the effect of nanostructure on the cell behaviors such as adhesion and growth rate. Nanoporous structures with various diameters (30, 40, 45, 50, 60 nm) and 500 nm of the depth were fabricated using the anodizing method. The water contact angle of the surface consisting of nanopores with 30 nm diameter was 40 degree and those were 60~70 degree in cases of nanopores with over 40 nm diameter. Hela cells were cultivated on various nanoporous structure surface to investigate the cell behavior on nanostructure. As a result, Hela cells preferred 30 nm diameter nanoporous surface that has lower water contact angle. This result was confirmed by protein adsorption experiment and scanning electron microscope investigation.

• 한국정보통신학회:학술대회논문집
• /
• 한국해양정보통신학회 2010년도 춘계학술대회
• /
• pp.814-817
• /
• 2010

다공성 알루미나 나노틀은 2단계의 양극산화 과정에 의해 세공의 직경이 균일하며, 배열이 규칙적이며 나노틀에 완벽하게 수직으로 배향되어 있다. 게다가 세공의 직경과 세공간의 간격은 양극산화시 전압과 전해질등을 바꾸어 주면 쉽게 조절할 수 있다. 금속을 세공내에 전기 화학적으로 탐지하면 각 세공 내에 규칙적인 직경의 금속 나노선이 생성된다.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
• /
• pp.77-78
• /
• 2006

We fabricated photonic crystals on GaAs and GaN substrates. After anodizing the aluminium thin film in electrochemical embient, the porous alumina was implemented to the mask for reactive ion beam etching process of GaAs wafer. And photonic crystals in GaN wafer were also fabricated using electron beam nano-lithography process. The coated PMMA thin film with 200 nm-thickness on GaN surface was patterned with triangular lattice and etched out the GaN surface by the inductively coupled plasma source. The fabricated GaAs and GaN photonic crystals provide the enhanced intensities of light emission for the wavelengths of 858 and 450 nm, respectively. We will present the detailed dimensions of photonic crystals from SEM and AFM measurements.

• 한국재료학회지
• /
• 제11권4호
• /
• pp.329-334
• /
• 2001

붕산용액에서 양극산화법으로 장벽형 산화피막을 형성시킨 후 미세조직을 관찰하였다. 양극산화시 인가되는 전압에 따른 피막의 성장속도는 1.54nm/v의 직선적인 관계를 나타냈으며 300v의 인가전압에서 생성된 산화피막의 조직은 50$0^{\circ}C$에서 열처리하였을 경우 피막의 상 전이가 일어나지 않았으나 높은 인가전압에서 생성된 산화피막의 경우는 피막의 조직이 비정질에서 ${\gamma}$-alumina로 변태되는 것이 관찰되었다. 또한 피막이 전자빔 조사에 의해서도 ${\gamma}$-alumina로 전이가 일어났다.

• 소성∙가공
• /
• 제29권3호
• /
• pp.127-134
• /
• 2020

It is known that the difference of texture of the polycrystalline Al sheet is not a critical parameter for the formation of aligned nanopore arrays in anodic aluminum oxide (AAO). This will be related to the polycrystalline grain in the Al sheet. The texture of each grain in the polycrystalline Al sheet is different. The mixed textures of grains have the mixing effects on the nanopore structure of the AAO. Thus, the effect of Al texture on the nanopore structure of the AAO was investigated using three types of Al single crystals with (111), (200) and (220) textures in this paper. These three types of AAO layers were fabricated by the two-step anodizing method at 40 V and temperature of 0-5℃ in oxalic acid solution. In the nanopores formed on the AAO, the average area of one nanopore and the average roundness of one nanopore were measured were measured based on the SEM images. In the hexagon obtained by connecting nanopores on the AAO, the average standard deviation of one angle deviated from 120° was measured. In the AAO nanopores with texture of (111), (200) and (220) single crystal samples, the average area of one nanopore of (200) single crystal sample was the widest, followed by (111), (220) single crystals. The average circularity of one nanopore of (200) single crystal sample was the best, followed by (111), (220) single crystals. The average standard deviation of an angle from 120° of (220) single crystal sample was the largest, followed by (111) and (200) single crystals.

• 공업화학
• /
• 제16권4호
• /
• pp.461-473
• /
• 2005

나노 기술은 현대 과학에 있어서 가장 주목 받고 있는 분야이며, 특히 나노미터 크기의 디멘션(dimension)을 가지는 나노 구조물의 제작은 나노 기술 연구의 출발점이며, 핵심 요소이다. 양극산화 알루미나 나노 템플레이트(anodicaluminum oxide or AAO nanotemplate) 기술은 상대적으로 공정이 쉽고 경제적이며, 대면적으로 나노 템플레이트의 제작이 가능하다는 장점을 가지고 있다. 또한 현재의 리소그래피 기술로는 달성하기 어려운 수준의 매우 큰 종횡비(aspect ratio)를 가능하게 하고, 조건을 변화시킴에 따라서 나노 템플레이트 기공의 직경 및 길이, 기공 밀도의 조절이 용이하다는 장점을 가지고 있어서 최근 10여 년간 매우 활발하게 이와 관련된 연구가 진행되어 왔으며, 다양한 나노 기술 분야로의 응용이 기대된다. 본 총설에서는 양극산화 알루미나 나노 템플레이트의 제조 및 응용에 대해 기술하였다.

• Korean Chemical Engineering Research
• /
• 제53권3호
• /
• pp.401-406
• /
• 2015

게터는 반도체와 초소형 전자패키지 소자 내부의 수소와 수증기 같은 기체를 흡착하여 기기 작동 시 방해 기체를 제거하는 기능을 한다. 본 연구에서는 재료와 공정 측면에서 높은 가격 경쟁력을 갖는 게터로, 실리콘 기판에 올라간 다공성 알루미나 구조체를 제조하는 연구를 진행하였다. 기공의 크기가 조절된 양극산화 알루미나(AAO)는 높은 비표면적을 가지며 표면에 OH-기를 다수 포함하므로 높은 효율을 갖는 수분 흡착제로 사용되었다. 등온 수분 흡탈착 곡선으로 분석한 수분 흡착도는 상대습도 35%일 때 2.02%로 우수한 성능을 나타내었다. 즉, 저온에서 사용가능하며, 추가 열원이 필요하지 않아 박막구조의 소형화가 용이하여 내부 손상 및 오염을 방지할 수 있는 게터재를 합성하였다.