• Corrosion Science and Technology
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• 제7권1호
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• pp.40-44
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• 2008

Passive metal forms an interfacial diffuse layer on the surface of passive film by its reaction with $H^+$ or $OH^-$ ions in solution depending on solution pH. There is a critical pH, called pH point of iso-selectivity ($pH_{pis}$) at which the nature of the diffuse layer is changed from the anion-permeable at pH<$pH_{pis}$ to the cation-permeable at pH>$pH_{pis}$. The $pH_{pis}$ for a passivated Fe was determined by examining the effects of pH on the thickness of passive film and on the dissolution reaction occurring on the passive film under a gavanostatic reduction in borate-phosphate buffer solutions at various pH of 7~11. The steady-state thickness of passive film formed on Fe showed the maximum at pH 8.5~9, and further the nature of film dissolution reaction was changed from a reaction producing $Fe^{3+}$ ion at $pH\leq8.5$ to that producing $FeO_2{^-}$ at $pH\geq9$, suggesting that the $pH_{pis}$ of Fe is about pH 8.5~9. In addition, the passive film formed at pH 8.5~9, $pH_{pis}$, was found to be the most protective with the lowest defect density as confirmed by the Mott-Schottky analysis. Pitting potential was decreased with increasing $Cl^-$ concentration at $pH\leq8.5$ due probably to the formation of anion permeable diffuse layer, but it was almost constant at $pH\geq9$ irrespective of $Cl^-$ concentration due primarily to the formation of cation permeable diffuse layer on the film, confirming again that $pH_{pis}$ of Fe is 8.5~9.

• 대한기계학회논문집A
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• 제39권12호
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• pp.1245-1249
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• 2015

본 연구에서는 나노스케일 박막의 표면주름 형성에 의한 산란반사도 향상을 평가하였다. 실리콘 기판 위에 120 nm 두께의 Poly(methyl metacrylate) 층을 스핀코팅(spin-coating)한 후, 20 nm 의 알루미늄 박막을 증착하여 시편을 제작하였다. 이를 오븐에서 $95^{\circ}C$의 온도로 2 시간 동안 풀림처리하여 표면주름을 형성하였다. 분광광도계로 가시광선 영역의 산란반사도를 측정한 결과 400 nm 파장에서 40%의 증가를 보였으며, 표면주름 위에 100 nm 의 은박막을 추가적으로 증착한 경우 산란반사도가 50%까지 향상되는 것을 확인하였다. 본 연구는 산란반사도의 증대를 요구하는 박막형 소자에 표면주름을 활할 수 있음을 제시한다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 추계학술대회 논문집
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• pp.95-98
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• 2009

This paper dealt with the design guide of the conventional edge-lit backlight optic with which the on-axis luminance could be increased by trying to improve the light condensing efficiency of a bright enhancement film (BEF). First, the general design guide concerned with the backlight optic was proposed, and then its validness was experimentally proved by conducting design examples with haze controls of both diffuse film and microdot material printed on the backside of the light guide plate. Experimental results showed that the variation range of the on-axis luminance by the present approach was about $5{\sim}9%$, which would be by no means negligible in the practical application.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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• pp.1739-1741
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• 2007

A 3D projection display using stacked screens to display the near and far images, respectively, is developed. The front screen is made of a scattering polarizer film, and the far image on the rear screen is clearly visible through it. The image is perceived as three-dimensional, and no eyestrain is suffered.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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• pp.259-259
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• 2015

Single crystalline indium-tin-oxide (ITO) nanowires (NWs) were grown by sputtering method. A thin Ni film of 5 nm was deposited before ITO sputtering. Thermal treatment forms Ni nanoparticles, which act as templates to diffuse Ni into the sputtered ITO layer to grow single crystalline ITO NWs. This Ni diffusion through an ITO NW was investigated by transmission electron microscope to observe the Ni-tip sitting on a single crystalline ITO NW. Meanwhile, a single crystalline ITO structure was found at bottom and body part of a single ITO NW without remaining of Ni atoms. This indicates the Ni atoms diffuse through the oxygen vacancies of ITO structure. Rapid thermal process (RTP) applied to generate an initial stage of a formation of Ni nanoparticles with variation in time periods to demonstrate the existence of an optimum condition to initiate ITO NW growth. Modulation in ITO sputtering condition was applied to verify the ITO NW growth or the ITO film growth. The Ni-assisted grown ITO layer has an improved electrical conductivity while maintaining a similar transmittance value to that of a single ITO layer. Electrically conductive and optically transparent nanowire-coated surface morphology would provide a great opportunity for various photoelectric devices.

• 한국광학회지
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• 제18권6호
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• pp.421-425
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• 2007

앞뒤로 겹쳐진 편광 선택성 이중스크린을 이용하는 후면투사 방식의 3D 프로젝션 디스플레이 시스템을 개발하였다. 전면과 후면 스크린은 산란형 편광필름을 이용하며, 각 스크린은 입사하는 빛의 편광상태에 따라 해당 빛을 확산-혹은 비확산-투과시킨다. 서로 수직인 선편광의 빛을 이용하여 근경과 원경을 각각 전면스크린과 후면스크린에 투사한다. 새로운 시스템은 넓은 시야각에 대하여 선명한 고해상도 영상을 제공한다. 영상의 입체감이 뛰어나고 시청자의 눈에 단지 2D 디스플레이 시스템이 주는 정도의 피로감만 야기한다.

• 대한핵의학회지
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• 제26권1호
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• pp.101-105
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• 1992

The leukemias represent diffuse lesions of the bone marrow and significant bony abnormalities are associated with the more aggressive varieties of leukemias and with the younger age groups. On plain film, several roentgenographic findings are observed such as diffuse osteopenia, radiolucent metaphyseal bands, osteolytic lesions and periostitis. We evaluated bone scintigraphic findings using $^{99m}Tc-methylene$ diphosphonate $(^{99m}Tc-MDP)$ in ten patients with proven leukemia. The scan is abnormal in 90%. We classified abnormal scintigraphic findings to 3 types and these are increased diffuse juxta-articular uptake, focal increase of uptake and combined type. The common sites of focal uptake were femur, humerus, tibia, spine, ribs, calvarium, scapula and mandible. We concluded that $(^{99m}Tc-MDP)$ bone scintigraphy is sensitive imaging modality in leukemic patients with bone pain.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.126.1-126.1
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• 2011

박막형 태양전지의 효율 향상을 위하여 광확산 패턴이 형성된 기판을 제작하고 이를 이용하여 비정질 실리콘 박막 태양전지를 제작하였다. 나노 임프린트 방법을 사용하여 제작된 광확산 패턴은 불규칙한 마이크로-나노 크기의 미세구조를 가지고 있어 빛의 확산투과 비율을 향상시켜주는 역할을 하였다. 제작된 광확산 기판위에 TCO물질을 증착하고, PECVD법을 사용하여 비정질 실리콘 p-i-n 접합 구조를 형성하였다. 제작된 태양전지 소자를 1.5 AM의 조건에서 I-V 특성을 분석하였으며, 비교군으로 사용된 일본 Asahi 사의 U-type glass에 비해 높은 Jsc 값을 나타내었다. 또한 외부양자효율을 측정함으로써 광확산 패턴에 의한 양자효율 변화를 확인 할 수 있었다.

• Applied Science and Convergence Technology
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• 제26권2호
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• pp.21-25
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• 2017

The shape of the reflection spectrum is complex and appears to overlap with several signals, because the surface state is uneven due to the natural oxide film, so that the spectrum becomes a complicated signal shape divided into regions 1 and 2 due to diffuse reflection. On the other hand, it is seen that the reflection spectrum after PEO surface treatment is overlapped with several signals. In addition, the reflectance of the energy band varies from 1.32 to 1.46 eV. Usually, the MgO-type oxide film was observed at an energy band of ~4.2 eV. The thickness of the oxide film was increased as the DC voltage was increased by the thin film thickness meter (QuaNix; 7500M) after Plasma Electrolytic Oxidation (; PEO) surface treatment. This is because the higher the DC voltage, the easier the binding of the $OH^-$ ions in the solution solution and the $Mg^+$ ions of the magnesium alloy. An important part of the bonding of ordinary ions is the energy source (plasma) which can promote bonding. However, when a certain threshold voltage or more is applied, the material is adversely affected. The oxide film of the surface may be destroyed without increasing the thickness of the oxide film, that is, whitening of the material may occur.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1992년도 추계학술대회 논문집
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• pp.67-72
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• 1992

In this paper, We prepared the thin film Cu-doped CdS Photovoltaic Cell, varying deposition condition by E-beam process and investigated its properties. After the Cu/CdS films were deposited on transparent ITO glass. We heat-treated to diffuse Cu atoms to CdS fi1m at 350[$^{\circ}C$]. With deposited Cu-doped CdS film. We investigated the electrical. optical. X-ray diffraction and junction property. We studied how to prepare the High conversion efficiency Solar cell window layer.