http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
분자동역학 시뮬레이션을 이용한 다이아몬드 나노임프린트 리소그라피에서의 점착에 관한 연구
김광섭(Kwang-Seop Kim),강지훈(Ji-Hoon Kang),김경웅(Kyung-Woong Kim) 한국트라이볼로지학회 2004 한국트라이볼로지학회 학술대회 Vol.39 No.-
In this paper, molecular dynamics simulations are performed to analyze the adhesion between a diamond mould and a copper substrate in diamond nanoimprint lithography. The diamond nanoimprint lithography process is simplified as punch-type nanoindentation. The copper substrates are assumed to monocrystalline and defect free and consist of 22500~80000 atoms depending on their dimension. The diamond moulds consist of 916 or 2414 atoms, which is assumed to be rigid. The consistent results for the maximum normal force and the adhesion force are obtained regardless of the size of substrates and the adhesion hysteresis is shown in all cases. It is found that the friction acting on the sidewalls of the mould affects the adhesion significantly when the mould is released from the substrate.
열 나노임프린트 리소그래피에서 사용되는 스탬프와 폴리머 재료 사이의 점착 특성
김광섭(Kwang-Seop Kim),강지훈(Ji-Hoon Kang),김경웅(Kyung-Woong Kim) 한국트라이볼로지학회 2006 한국윤활학회지(윤활학회지) Vol.22 No.4
In this paper, the adhesion characteristics between a fused silica without or with an anti-sticking layer and a thermoplastic polymer film used in thermal NIL were investigated experimentally in order to identify the release performance of the anti-sticking layer. The anti-sticking layers were derived from fluoroalkylsilanes, (1H, 1H, 2H, 2H-perfluorooctyl)trichlorosilane (F13-OTS) and (3, 3, 3-trifluoropropyl)trichlorosilane (FPTS), and coated on the silica surface in vapor phase. The commercial polymers, mr-I 7020 and 8020 (micro resist technology, GmbH), for thermal NIL were spin-coated on Si substrate with a rectangular island which was fabricated by conventional microfabrication process to achieve small contact area and easy alignment of flat contact surfaces. Experimental conditions were similar to the process conditions of thermal NIL. When the polymer film on the island was separated from the silica surface after imprint process, the adhesion force between the silica surface and the polym film was measured and the surfaces of the silica and the polymer film after the separation were observed. As a result, the anti-sticking layers remarkably reduced the adhesion force and the surface damage of polymer film and the chain length of silane affects the adhesion characteristics. The anti-sticking layers derived from FPTS and F13-OTS reduced the adhesion force per unit area to 38% and 16% of the silica surfaces without an anti-sticking layer, respectively. The anti-sticking layer derived from F13-OTS was more effective to reduce the adhesion, while both of the anti-sticking layers prevented the surface damages of the polymer film. Finally, it is also found that the adhesion characteristics of mr-I 7020 and mr-I 8020 polymer films were similar with each other.
열가소성 폴리머 필름의 나노 응착 및 마찰 거동에 대한 온도의 영향
김광섭(Kwang-Seop Kim),安藤泰久(Yasuhisa Ando),김경웅(Kyung-Woong Kim) 한국트라이볼로지학회 2007 한국윤활학회지(윤활학회지) Vol.23 No.6
Adhesion and friction tests were carried out in order to investigate the effect of temperature on the tribological characteristics of poly (methylmethacrylate) (PMMA) film using AFM. The pull-off and friction forces on the PMMA film were measured under a high vacuum condition (below 1×10?⁴ Pa) as the temperature of the PMMA film was increased from 300 K to 420 K (heating) and decreased to 300K (cooling). Friction tests were also conducted in both high vacuum and air conditions at room temperature. When the temperature was 420 K, which is 25 K higher than the glass transition temperature (Tg) of PMMA, the PMMA film surface became deformable. Subsequently, the pull-off force was proportional to the maximum applied load during the pull-off force measurement. In contrast, when the temperature was under 395 K, the pull-off force showed no correlation to the maximum applied load. The friction force began to increase when the temperature rose above 370 K, which is 25 K lower than the Tg of PMMA, and rapidly increased at 420 K. Decrease of the PMMA film stiffness and plastic deformation of the PMMA film were observed at 420 K in force-displacement curves. After the heating to 420 K, the fiction coefficient was measured under the air condition at room temperature and was found to be lower than that measured before the heating. Additionally, the RMS roughness increased as a result of the heating.