• Laser Solutions
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• v.8 no.2
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• pp.21-32
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• 2005

The excimer laser ablation of a polymer occurs by the excitation of chemical bonds to energy levels that are above the dissociation energy. In this process, however, fragmented debris is finally ejected explosively by the scission of bonds and accumulates on the material surface. In the present work, a process for eliminating surface debris contamination generated by the laser ablation of a polymer is developed. The proposed approach for removing surface debris utilizes an erasable ink pasted on a polymide. The ink pasted polyimide is ablated by KrF excimer laser. The surface debris ejected from the polyimide is then combined with the ink layer on the polymer. Finally, both the surface debris and the ink layer are removed using adhesive tape or alcohol solvent. The results suggest that the erasable ink method is a simple, low cost, and extremely effective debris eliminating process.

• Proceedings of the Materials Research Society of Korea Conference
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• 1994.11a
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• pp.60-60
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• 1994

• Proceedings of the Materials Research Society of Korea Conference
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• 2012.05a
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• pp.81.1-81.1
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• 2012

나노임프린트 리소그라피(Nano-Imprint Lithography, NIL) 기술은 기판위의 resin을 나노구조물이 각인된 스탬프로 눌러서 나노구조물을 형성하는 기술로, 경제적이고 효과적으로 나노구조물을 제작할 수 있는 기술이다. 그중에서도 UV 기반의 나노임프린트(UV-NIL) 기술은 resin을 투명한 스탬프로 누른뒤 UV로 경화시켜 나노구조물을 형성하는 기술로써 고온, 고압($140{\sim}180^{\circ}C$, 10~30bar)이 필요한 가열식 나노임프린트 기술에 비해 상온, 상압($20^{\circ}C$, 1bar)에서도 구조물 형성이 가능하여 다층구조 형성에 적합하다. 연속적인 임프린팅 공정에 의해 resin이 quarz 스탬프에 잔류하여 패터닝에 결함을 유발하게 되므로 오염물을 제거하기 위한 세정공정이 필요하다. 하지만 UV에 의해 경화된 resin은 cross-linking을 형성하여 화학적인 내성이 증가하게 되므로 제거하기가 어렵다. 현재는 resin 제거를 위한 세정공정으로 SPM($H_2SO_4/H_2O_2$) 세정이 사용되고 있는데 세정시간이 길고 세정 후에 입자 또는 황 잔유물이 남으며 많은 유해용액 사용의 문제점이 있어 효과적으로 resin을 제거할 세정공정이 필요한 상황이다. 본 연구에서는 친환경적인 UV 세정 및 오존수 세정공정을 적용하여 경화된 resin을 제거하는 연구를 진행하였다. 실험샘플은 약 100nm 두께의 resin을 증착한 $1.5cm{\times}1.5cm$ $SiO_2$ 쿠폰 wafer를 사용하였으며, UV 및 오존수의 처리시간을 달리하여 resin 제거효율을 평가하였다. ATR-FTIR 장비를 사용하여 시간에 따른 resin의 두께를 측정한 결과, UV 세정으로 100nm 높이의 resin중에 80nm의 bulk resin이 단시간에 제거가 되었고 나머지 20nm의 resin thin film은 오존수 세정으로 쉽게 제거되는 것을 확인 하였다. 또한 표면에 남은 resin residue와 particle을 제거하기 위해서 SC-1 세정을 진행하였고 contact angle과 optical microscope 장비를 사용하여 resin이 모두 제거된 것을 확인하였다.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.29A no.1
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• pp.33-40
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• 1992

Several etching phenomena were observed and analyzed in diaphragm process performed on 4-inch (100) Si wafers for sensor application. In case of deep etching to above 300$\mu$m depth, the etch-defects appeared at etched surface could be classified into three categories such as hillocks, reaction products, and white residues. It was known that the hillock had a pyramidal shape or trapizoidal hexahedron structure depending on the density and size of the reaction products. The IR spectra showed that the white residue, which was due to the local over-saturation of Si dissolved in solution, was mostly Si-N-O compounds mixed with a small amount of H and C etc. Also, the difference in both the existence of etch-defects and etch rate distribution over a whole wafer was investigated when the etched surfaces were downward, upward horizontally and erective in etching solutions. The obtained data were analyzed through flow pattern in the etching bath. As the results, the downward and erective postures were favorable in the etch rate uniformity and the etch-defect removal, respectively.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.11
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• pp.2525-2531
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• 2012

Al-Cu alloy has been used as a circuit material for its low resistance and ease to process for long years at CMOS technology. However, basically metal is very susceptible to corrosion and which has been a long pending trouble in various fields using metal. The defect causes the reliability concerns, so improved methods are necessary to reduce the defect. In the various corrosion parameters, PR strip process conditions after metal etch and optimal cleaning solutions are controllable and increase the process margin to prevent the metal corrosion. This study proposes that chlorine residue after metal etch as the source of metal corrosion, and charges should be removed by optimizing PR strip process condition and cleaning condition.

• Korean Chemical Engineering Research
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• v.54 no.4
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• pp.548-554
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• 2016

In this study, semi-aqueous solutions containing carboxylic acids such as oxalic acid (OA), lactic acid (LA) and citric acid (CA) were formulated for the removal of copper etching residues produced at the interconnection process, and their characteristics were analyzed. Carboxylic acids in the solutions were apt to form various copper complexes according to the value of pH. Semi-aqueous solution containing 10 wt% CA showed the lowest etching rate of copper in the range from pH2 to pH7 and the highest selectivity in the range of pH 2 to pH 4. However, the cleaning solution containing 10 wt% LA revealed the superior selectivity at the range from pH 5 to pH 7. Appropriate selection of carboxylic acid should be required to improve the performance of cleaning solution. In the case of CA, the etching selectivity of copper oxide complex to copper was increased with the concentration of CA in the solution, when the solutions contain over 5 wt% CA, the copper interconnection layer has a metallic copper surface more than 88% in the area. The result shows that CA contained semi-aqueous solution has a relatively good cleaning ability.

• Journal of the Microelectronics and Packaging Society
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• v.13 no.3 s.40
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• pp.47-51
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• 2006

Recently, CMP (Chemical Mechanical Polishing) is one of very important processing in semiconductor technology because of large integration and application of design role. CMP is a planarization process of wafer surface using the chemical and mechanical reactions. One of the most important components of the CMP system is the polishing pad. During the CMP process, the pad itself becomes smoother and glazing. Therefore it is necessary to have a pad conditioning process to refresh the pad surface, to remove slurry debris and to supply the fresh slurry on the surface. A conditioning disk is used during the pad conditioning. There are diamonds on the surface of diamond disk to remove slurry debris and to polish pad surface slightly, so density, shape and size of diamond are very important factors. In this study, we characterized diamond disk with 9 kinds of sample.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.24 no.2
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• pp.65-71
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• 2018

Paper packs, glass bottles, metal cans, and plastic materials are classified according to packaging material recycling groups that are Extended Producer Responsibility (EPR). In the case of waste paper pack, the compressed cartons are dissociated to separate polyethylene films and other foreign substance, and then these are washed, pulverized and dried to produce toilet paper. Glass bottle for recycling is provided to the bottle manufacturers after the process of collecting the waste glass bottle, removing the foreign substance, sorting by color, crushing, raw materializing process. Waste glass recycling technology of Korea is largely manual, except for removal of metal components and low specific gravity materials. Metal can is classified into iron and aluminum cans through an automatic sorting machine, compressed, and reproduced as iron and aluminum through a blast furnace. In the case of composite plastic material, the selected compressed product is crushed and then recycled through melt molding and refined products are produced through solid fuel manufacturing steps through emulsification and compression molding through pyrolysis. In the recycling process of paper packs, glass bottles, metal cans, and plastic materials, the influx of recycled materials and other substances interferes with the recycling process and increases the recycling cost and time. Therefore, the government needs to improve the legal system which is necessary to use materials and structure that are easy to recycle from the design stage of products or packaging materials.