• Korean Chemical Engineering Research
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• 제54권4호
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• pp.548-554
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• 2016

Damascene 구조를 갖는 반도체소자의 구리금속배선 식각공정에서 배선재료에 의해서 발생되는 구리 식각잔류물을 제거하기 위해 oxalic acid (OA), lactic acid (LA) 및 citric acid (CA)의 카르복시산 함유된 반수계 혼합세정액을 제조하고 특성을 분석하였다. 카르복시산은 pH에 따라 카르복실기와 구리이온들과의 다양한 복합체를 형성하며 세정특성의 변화를 준다. 카르복시산들이 함유된 각각의 세정액의 세정특성평가결과 10 wt% CA를 함유한 반수계 세정액의 식각잔류물 세정특성은 pH 2에서 7까지의 영역에서 가장 낮은 구리 식각률을 보였으며 pH 2에서 4까지 구리에 대한 구리산화물의 가장 높은 식각 선택도를 나타내었으나 pH 5에서 7 범위에서는 10 wt% LA가 함유된 세정액이 더 높은 선택도를 보였다. 따라서 표면세정효과는 pH에 따라 변화하며 적절한 카르복시산을 사용함이 요구된다. CA가 함유된 세정액의 경우에 CA 농도와 구리에 대한 구리산화물의 식각 선택도의 증가특성을 보이며 CA가 5 wt%이상 함유된 경우에는 세정 후 구리배선의 표면이 88 %이상의 금속구리로 분석되어 구리산화물로 구성된 식각 잔류물의 제거에 효과적임을 알 수 있었다.

• Corrosion Science and Technology
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• 제9권6호
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• pp.276-280
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• 2010

Copper(Cu) as an interconnecting metal layer can replace aluminum (Al) in IC fabrication since Cu has low electrical resistivity, showing high immunity to electromigration compared to Al. However, it is very difficult for copper to be patterned by the dry etching processes. The chemical mechanical polishing (CMP) process has been introduced and widely used as the mainstream patterning technique for Cu in the fabrication of deep submicron integrated circuits in light of its capability to reduce surface roughness. But this process leaves a large amount of residues on the wafer surface, which must be removed by the post-CMP cleaning processes. Copper corrosion is one of the critical issues for the copper metallization process. Thus, in order to understand the copper corrosion problems in post-CMP cleaning solutions and study the effects of DC biases and post-CMP cleaning solution concentrations on the Cu film, a constant voltage was supplied at various concentrations, and then the output currents were measured and recorded with time. Most of the cases, the current was steadily decreased (i.e. resistance was increased by the oxidation). In the lowest concentration case only, the current was steadily increased with the scarce fluctuations. The higher the constant supplied DC voltage values, the higher the initial output current and the saturated current values. However the time to be taken for it to be saturated was almost the same for all the DC supplied voltage values. It was indicated that the oxide formation was not dependent on the supplied voltage values and 1 V was more than enough to form the oxide. With applied voltages lower than 3 V combined with any concentration, the perforation through the oxide film rarely took place due to the insufficient driving force (voltage) and the copper oxidation ceased. However, with the voltage higher than 3 V, the copper ions were started to diffuse out through the oxide film and thus made pores to be formed on the oxide surface, causing the current to increase and a part of the exposed copper film inside the pores gets back to be oxidized and the rest of it was remained without any further oxidation, causing the current back to decrease a little bit. With increasing the applied DC bias value, the shorter time to be taken for copper ions to be diffused out through the copper oxide film. From the discussions above, it could be concluded that the oxide film was formed and grown by the copper ion diffusion first and then the reaction with any oxidant in the post-CMP cleaning solution.

• 한국재료학회지
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• 제25권9호
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• pp.462-467
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• 2015

Pellicle is defined as a thin transparent film stretched over an aluminum (Al) frame that is glued on one side of a photomask. As semiconductor devices are pursuing higher levels of integration and higher resolution patterns, the cleaning of the Al flame surface is becoming a critical step because the contaminants on the Al flame can cause lithography exposure defects on the wafers. In order to remove these contaminants from the Al frame, a highly concentrated nitric acid ($HNO_3$) solution is used. However, it is difficult to fully remove them, which results in an increase in the Al surface roughness. In this paper, the pellicle frame cleaning is investigated using various cleaning solutions. When the mixture of sulfuric acid ($H_2SO_4$), hydrofluoric acid (HF), hydrogen peroxide ($H_2O_2$), and deionized water with ultrasonic is used, a high cleaning efficiency is achieved without $HNO_3$. Thus, this cleaning process is suitable for Al frame cleaning and it can also reduce the use of chemicals.

• The Journal of Advanced Prosthodontics
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• 제7권2호
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• pp.151-159
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• 2015

PURPOSE. To describe and characterize the surface topography and cleanliness of CAD/CAM manufactured zirconia abutments after steaming and ultrasonic cleaning. MATERIALS AND METHODS. A total of 12 ceramic CAD/CAM implant abutments of various manufacturers were produced and randomly divided into two groups of six samples each (control and test group). Four two-piece hybrid abutments and two one-piece abutments made of zirconium-dioxide were assessed per each group. In the control group, cleaning by steam was performed. The test group underwent an ultrasonic cleaning procedure with acetone, ethyl alcohol and antibacterial solution. Groups were subjected to scanning electron microscope (SEM) analysis and Energy-dispersive X-ray spectroscopy (EDX) to verify and characterize contaminant chemical characterization non- quantitatively. RESULTS. All zirconia CAD/CAM abutments in the present study displayed production-induced wear particles, debris as well as organic and inorganic contaminants. The abutments of the test group showed reduction of surface contamination after undergoing an ultrasonic cleaning procedure. However, an absolute removal of pollutants could not be achieved. CONCLUSION. The presence of debris on the transmucosal surface of CAD/CAM zirconia abutments of various manufacturers was confirmed. Within the limits of the study design, the results suggest that a defined ultrasonic cleaning process can be advantageously employed to reduce such debris, thus, supposedly enhancing soft tissue healing. Although the adverse long-term influence of abutment contamination on the biological stability of peri-implant tissues has been evidenced, a standardized and validated polishing and cleaning protocol still has to be implemented.

• 멤브레인
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• 제27권6호
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• pp.519-527
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• 2017

멤브레인 파울링은 지표수를 처리하는 저압 멤브레인 기술 적용의 확장에 있어 큰 장애가 된다. 따라서 파울링 제어를 위한 주기적인 수리학적 세정기술의 최적화는 매우 중요하다. 주기적인 수리학적 세정과 이와 연관된 파울링 현상에 관한 올바른 이해는 멤브레인 세정 전략을 최적화하기 위해 매우 유용할 수 있다. 실험적으로 측정한 투과도와 전통적인 Hermia 파울링 모델 예측 치의 비교를 통해, 본 연구에서는 합성 탁도유발 시료를 처리하는 가압식 멤브레인 공정에서 30분 여과와 정세정/역세정이 포함된 1분 세정조건을 바탕으로 6번의 운전사이클을 통해 발생하는 파울링 현상을 분석하고 이를 통해 지배적인 파울링 기작을 정량적으로 이해하고자 하였다. 단독 세정에서, 첫 번째 운전사이클에서 발생하는 파울링은 완전공극막힘 현상에 의해 주로 지배되었고 마지막 운전 사이클에서는 케이크 형성이 지배적인 파울링 기작으로 관찰되었다. 정세정과 역세정이 혼합된 경우, 파울링 속도는 감소하였으나 전반적으로 케이크 형성이 주 파울링 기작으로 관찰되었다.

• 보존과학회지
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• 제11권1호
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• pp.28-37
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• 2002

문화재 보존을 위한 처리 과정에는 반드시 세척이 행하여지며, 이 때 세척은 완벽한 세정뿐만 아니라 2차 오염 발생이나 훼손 등에 각별히 조심하여야 한다. 따라서 본 연구에서는 보다 과학적인 방법으로 석조문화재 보존 처리용 세정제를 개발하기 위하여, 국내 석조물에 기생하는 미생물과 오물을 시료로 채취하여 FT-IR분석을 통하여 석재 오물의 화학적인 관능기를 파악하고, 각종 용매를 처리하여 그 용출 특성을 파악하였으며, 세정제에 의한 세정 효과와 풍화율에 대하여 연구하였다. 실험 결과로부터 석재 문화재 세정용 계면활성제로는 산성용액에서도 안정하며, 석재 구성물질과의 반응성이 적고, 각종 2차 오염 발생 가능성이 적으며, 산화제와 산의 활성을 증가시킬 수 있는 비이온 계면활성제가 적당한 것으로 판단되었다. 본 연구에서 개발한 $H_2O_2/HF/NP-10$ 복합형 세정제는 적용실험 결과, 석조 문화재 처리용 세정제로서 좋은 세정력을 가지고있는 것으로 판단된다.

• 한국표면공학회지
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• 제49권6호
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• pp.513-520
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• 2016

Many surface protection methods have been developed to apply to constructional steels which have been used under severe corrosive environments. One of these methods, hot dip galvanizing is being widely used to the numerous constructional steels such as a guard rail of high way, various types of structural steel for manufacturing ship and for some other industrial fields etc.. Recently, the cost of zinc is getting higher and higher, thus, it is considered that improvement of hot dip galvanizing process to reduce the cost of production should be developed possibly. In this study, additives such as acid cleaning solution, $NH_4OH$, $Al(OH)_3$ and $H_2O_2$ were added to flux solution, and omission of water washing treatment after acid cleaning was investigated with some types of flux solutions added with some additives mentioned above. The decrement of pH by adding the acid cleaning solution could be controlled due to neutralization reaction with addition of $NH_4OH$. The flux solution added with both $NH_4OH$ and $Al(OH)_3$ exhibited nearly the same color and pH value as those of orignal flux solution with no added, and the sample dipped to the flux solution which was added with additives mentioned above indicated a relatively good corrosion resistance compared to other samples. However, the flux solution added with $NH_4OH$, $Al(OH)_3$ and $H_2O_2$ exhibited a different color, sediment and a bad corrosion resistance. Consequently, it is considered that omission of water washing treatment may be able to perform by adding optimum additives to the original flux solution.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 전력전자학술대회 논문집
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• pp.296-297
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• 2001

In this paper, the minimization of particle wit introduction of face to face to face type in cleaning. Easy input and change of parameter Monitoring function of process data in process function of 3 moving axis. Return Tank for Chem cal solution

• 한국재료학회:학술대회논문집
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• 한국재료학회 2005년도 춘계학술발표대회 및 제8회 신소재 심포지엄 논문개요집
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• pp.56-56
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• 2005

• 한국건설순환자원학회논문집
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• 제8권3호
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• pp.356-364
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• 2020

본 연구에서는 광촉매를 혼입한 모르타르의 방오성능을 평가하기 위해 메틸렌 블루를 이용한 실험 연구를 수행하였다. 실험 시편은 시멘트 중량대비 2.5%, 5.0%, 7.5% 및 10.0%의 광촉매를 혼입하여 모르타르 시편을 제작하였고, 시편 표면에 스크래치 형태로 조도를 설정하였다. 표면 조도는 3가지로 조도가 없는 경우, 조도가 작은 경우(중간 조도), 조도가 큰 경우(거친 조도)로 설정하였다. 모르타르 시편 제작 후 24시간 동안 자외선램프 조사와 12시간 동안 메틸렌 블루 컨디셔닝 용액에 침지 하는 전처리 과정을 진행하였다. 실험챔버에 전처리가 완료된 모르타르 시편을 배치 후 48시간 동안 자외선램프를 조사하였고 시간에 따라 메틸렌 블루 수용액의 색 변화를 분광측색계를 이용하여 측정하였다. 광촉매의 혼입량이 증가할수록 메틸렌 블루 색 변화는 증가하는 경향을 나타내며 이는 방오성능이 증가하는 것을 의미한다. 반면에 표면조도가 증가할수록 메틸렌 블루 용액의 색 변화는 뚜렷한 경향은 나타내지 않으며 표면의 광촉매 분포가 일정하지 않기 때문이다.