• 한국가시화정보학회지
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• 제19권3호
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• pp.123-129
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• 2021

Many plants and animals in nature have superhydrophobic surfaces. This superhydrophobic surface has various properties such as self-cleaning, moisture collection, and anti-icing. In this study, the superhydrophobic properties of PTFE surface were treated by plasma etching. There were four important factors that changed the surface properties. Micro-sized protrusions were formed by plasma etching. The most influential parameter was RF Power. The contact angle of the pristine PTFE surface was about 113.8°. The maximum contact angle of the surface after plasma treatment with optimized parameters was about 168.1°. In this case, the sliding angle was quite small about 1°. These properties made it possible to remove droplets easily from the surface. To verify the self-cleaning effect of the surface, graphite was used to contaminate the surface and remove it with water droplets. Graphite particles were easily removed from the optimized surface compared to the pristine surface. As a result, a surface having water repellency and self-cleaning effects could be produced with optimized plasma etching parameters.

• 한국표면공학회지
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• 제31권6호
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• pp.407-416
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• 1998

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.99.2-99.2
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• 2010

This paper investigates the dependence of a-Si:H/c-Si passivation and heterojunction solar cell performances on various cleaning processes of silicon wafer and surface morphology. It is observed that passivation quality of a-Si:H thin-films on c-Si wafer highly depends on wafer surface conditions. The MCLT(Minority carrier life time) of wafer incorporating intrinsic (i) a-Si:H as a passivation layer shows sensitive variation with cleaning process and surface morpholgy. By applying improved cleaning processes and surface morphology we can obtain the MCLT of $200{\mu}sec$ after H-termination and above 1.5msec after i a-Si:H thin film deposition, which has implied open circuit voltage of 0.720V.

• 한국재료학회지
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• 제22권9호
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• pp.459-464
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• 2012

We investigated cleaning effects using $NH_4OH$ solution on the surface of Cu film. A 20 nm Cu film was deposited on Ti / p-Si (100) by sputter deposition and was exposed to air for growth of the native Cu oxide. In order to remove the Cu native oxide, an $NH_4OH$ cleaning process with and without TS-40A pre-treatment was carried out. After the $NH_4OH$ cleaning without TS-40A pretreatment, the sheet resistance Rs of the Cu film and the surface morphology changed slightly(${\Delta}Rs:{\sim}10m{\Omega}/sq.$). On the other hand, after $NH_4OH$ cleaning with TS-40A pretreatment, the Rs of the Cu film changed abruptly (${\Delta}Rs:till{\sim}700m{\Omega}/sq.$); in addition, cracks showed on the surface of the Cu film. According to XPS results, Si ingredient was detected on the surface of all Cu films pretreated with TS-40A. This Si ingredient(a kind of silicate) may result from the TS-40A solution, because sodium metasilicate is included in TS-40A as an alkaline degreasing agent. Finally, we found that the $NH_4OH$ cleaning process without pretreatment using an alkaline cleanser containing a silicate ingredient is more useful at removing Cu oxides on Cu film. In addition, we found that in the $NH_4OH$ cleaning process, an alkaline cleanser like Metex TS-40A, containing sodium metasilicate, can cause cracks on the surface of Cu film.

• 보존과학회지
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• 제27권3호
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• pp.333-344
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• 2011

철제유물의 보존처리 과정 중 표면 이물질 제거는 유물의 원형을 찾아주는 중요한 단계이다. 현재 표면 이물질 제거 시 가장 많이 사용하는 sand blaster (air brasive)의 경우, 분사되는 유리가루는 인체에 유해하고 환경오염을 유발하는 주요한 물질이다. 그러므로 이런 문제점을 보완하기 위해 타 산업분야에서 친환경세정장비로 많이 쓰이고 있는 $CO_2$ snow cleaning을 철제유물 표면 이물질 제거에 적용하여 비교·연구 하였다. 실험은 부식시험편과 철제유물에 sand blaster와 $CO_2$ snow cleaning을 적용하여 비교 분석하였다. 부식시험편의 경우, sand blaster와 $CO_2$ snow cleaning 방법 모두 이물질 제거 정도, 표면 거칠기, 색도 측정 결과가 유사하게 나타났으며, 특히 SEM을 통해 $CO_2$ snow cleaning을 적용한 부식시험편은 sand blaster에 비해 표면을 마모시키지 않는 것을 확인하였다. 또한 철제유물에 적용한 경우, $CO_2$ snow cleaning의 power nozzle은 sand blaster에 비해 표면을 마모시키지 않고 고른 표면을 유지하는 등 세정효과가 우수하게 나타났다. 그리고 X-ray촬영을 통해 이물질 제거 전과 후 금속 내부의 구조적 변화는 없음을 관찰하였다. 결론적으로 sand blaster와 $CO_2$ snow cleaning의 power nozzle은 이물질 제거 효과가 유사함을 확인할 수 있었다. 그러나 $CO_2$ snow cleaning의 power nozzle을 철제유물에 적용하여도 sand blaster와 유사한 효과는 얻을 수 있으나, 분사압력이 높을 경우 철제 유물이 손상될 우려가 있으므로 유물 내부 상태에 따라 적용여부를 판단해야 함을 본 실험을 통하여 알 수 있었다.

• 한국디지털건축인테리어학회논문집
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• 제13권4호
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• pp.61-68
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• 2013

Concrete structure is not the only material vulnerable to physical and chemical processes of deterioration associates with severe conditions. Deterioration of the concrete structure, however, occurs more progressively from the outside of the concrete exposed to severe conditions. Especially, Carbonation, chloride ion attack is more important factor of concrete durability. This study is interested in manufacturing the self-cleaning concrete surface impregnant including TEOS, lithium silicate for the repair of the exposed concrete surface and the color concrete requiring the advanced function in view of the concrete appearance. Form the results, TEOS and lithium silicate are very effective that increasing the concrete durability using self-cleaning concrete impregnant. Self-cleaning concrete impregnant specimens is satisfied with performance requirement of KS standard in adhesion test in tension but the reinforcement of concrete substrate is slight. So, the self-cleaning concrete impregnant of this study is more desirable for the improvement of durability rather than the reinforcement.

• 한국표면공학회지
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• 제45권4호
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• pp.143-150
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• 2012

Laser cleaning have been found to be a useful cleaning tool to remove contaminants without inducing damage to the substrate and making secondary pollutant. In this study, the effect of Nd:YAG laser cleaning system, emitting at 1064 nm and 532 nm, on acrylic resin applied onto copper coupons and pieces of bronze was investigated. The samples after laser cleaning tests were examined using microscopy, FT-IR, SEM-EDS. As a result, the acrylic resin could be removed from most of the samples at low laser energy density. Laser wavelength 532 nm was more effective than 1064 nm because of using lower laser energy density, which could reduce heat damage to substrates. Although the acrylic resin was easily removed, it revealed melted surfaces and removed bronze patina which must remain. The problems should be solved by future studies using different laser system or laser wavelengths.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2003년도 춘계학술발표회 초록집
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• pp.54-54
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• 2003

MgO layer는 POP 패빌 내 유전증을 이온의 스퍼터링으로부터 보호하여 주며, 또한 높은 이차 전자 밤출 계수의 특성을 가지고 있어 구동 및 유지 전압을 낮춰 주는 역할을 한다. 그러나. MgO layer는 $H_20,{\;}CO_2,{\;}N_2,{\;}0_2$ 그리고 $H_2$와 같은 불순물 들을 쉽게 를착하는 단점이 있어, PDP의 특성 및 수명 단축에 영향을 줄 수 있다. 따라서, 본 연구에서는 atmospheric pressure plasma cleaning 과 low pressure i inductively coupled plasma (ICP) cleaning 처리에 의하여, 보호층으로 사용이 되는 MgO layer의 outgassing 특성을 조사하고자 한다. plasma cleaning에 의한 MgO layer 표면의 roughness와 불순물의 변화를 알아보기 위 하여 atomic force microscopy(AFM)과 x-ray p photoelectron spectroscopy(XPS)를 이용하여 측정 하였다. 또한, outgassing의 특성을 분석하기 위하여 MgO layer를 $400^{\circ}C$ 까지 온도를 가하여 온도에 따른 outgassing의 특성을 quadrupole mass spectrometer(QMS)를 이용하여 알아보았다. atmospheric pressure plasma cleaning 에서는 $He/O_2/Ar/N_2$의 gas를 사용하였으며, low pressure ICP cleaning 에 서는 Ar의 gas를 사용하였다. atmospheric pressure plasma cleaning는 low pressure ICP C cleaning과 비교해 더 낮은 outgassing을 관잘 할 수 있었으나. MgO 표면의 roughness는 low pressure ICP cleaning 후 더 낮은 것을 알 수 있었다. 또한 $He/O_2/Ar/N_2$의 gas를 사용 한 atmospheric pressure plasma cleaning 과 $Ar/O_2$의 gas를 사용한 ICP cleaning에서 이 차전자방출계수(SEEC)가 약 1.5~2.5배 증가된 것을 알 수 있었다.

• 수산해양기술연구
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• 제51권4호
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• pp.576-582
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• 2015

The efficiencies of thermal power system using fossil fuel depend on heat exchangers which extract energy from the exhaust gas before it is expelled to the atmosphere. To increase heat transfer efficiency it is very important to maintain the surface of heat exchanger as clean condition. The accepted skill of cleaning of fouled surface of heat exchanger is soot blowing. A high pressure jet of air is forced through the flat surface of plate to remove the deposit of fouling. There is, however, little knowledge of the fundamental principles of how the jet behave on the surface and how the jet actually removes the deposit. Therefore, the study focuses on the measuring of cleaning area and cleaning dwell time after accumulating the simulated deposit on the flat surface. The deposit test rig was built for the study and simulated deposit material is used after measuring the physical property of the each material by shearing stress test. Much data was obtained for the analysis by the parameters change such as the different jet speed, different inner pressure and variable distance of the jet from the test rig surface. The experimental data was compared with the theoretical equation and most of the data matches well except some extreme cases.

• Bulletin of the Korean Chemical Society
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• 제18권7호
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• pp.737-740
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• 1997

The influence of cyclic treatments with H2O2/DIW (1 : 10) and HF/DIW (1 : 100) on the roughness of silicon surface in the wet chemical processing was investigated by atomic force microscopy (AFM). During the step of the SC-1 cleaning, there is a large increase in roughness on the silicon surface which will result in the poor gate oxide breakdown properties. The roughness of the silicon wafer after the SC-1 cleaning step was reduced by cyclic treatments of hydrogen peroxide solution and hydrofluoric acid solution instead of HF-only cleaning. AFM images after each step clearly illustrated that the average roughness of silicon surface after three times treatments with H2O2 and HF solutions was reduced by 10 times compared with that after the SC-1 cleaning step.