The Experts below are selected from a list of 279 Experts worldwide ranked by ideXlab platform
Dahl-young Khang - One of the best experts on this subject based on the ideXlab platform.
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Low Pressure nanoimprint lithography
Nano Letters, 2004Co-Authors: Dahl-young Khang, Hyewon Kang, Tae-il Kim, Hyun Jung LeeAbstract:A Low Pressure (2∼3 bar) nanoimprint lithography technique is developed that utilizes a thin fluoropolymer film (∼100 μm) mold. The flexible film mold alLows imprinting of submicron pattern features at such a Low Pressure primarily due to “sequential” imprinting made possible by the mold flexibility and the conformal contact made between the film mold and the substrate. The surface energy of the fluoropolymer mold material is Low enough that no mold surface treatment is needed for clean demolding. Easy replication of the film mold by a simple solvent casting is another advantage of the proposed method. Also the nanoscale (<100 nm) replication capability is demonstrated and discussed with a solvent-cast thin film fluoropolymer mold.
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Low-Pressure nanoimprint lithography
Nano Letters, 2004Co-Authors: Dahl-young Khang, Hyewon Kang, Tae-il Kim, Hong H. LeeAbstract:A Low Pressure (2similar to3 bar) nanoimprint lithography technique is developed that utilizes a thin fluoropolymer film (similar to100 mum) mold. The flexible film mold alLows imprinting of submicron pattern features at such a Low Pressure primarily due to "sequential" imprinting made possible by the mold flexibility and the conformal contact made between the film mold and the substrate. The surface energy of the fluoropolymer mold material is Low enough that no mold surface treatment is needed for clean demolding. Easy replication of the film mold by a simple solvent casting is another advantage of the proposed method. Also the nanoscale (
Jean-paul Booth - One of the best experts on this subject based on the ideXlab platform.
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Anomalous collisionality in Low-Pressure plasmas
Physics of Plasmas, 2013Co-Authors: Trevor Lafleur, Pascal Chabert, M.m. Turner, Jean-paul BoothAbstract:Based on a theoretical argument from fundamental kinetic theory, by way of simple worked examples, and through the use of particle-in-cell simulations of capacitively coupled plasmas, we demonstrate that conventional methods for calculating the momentum transfer collision frequency in Low-Pressure plasmas can be seriously erroneous. This potentially plays an important and previously unconsidered role in many Low-Pressure discharges, and at least in part provides a possible explanation for anomalous behaviour often encountered in these plasmas.
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Extinction of RF capacitive Low-Pressure discharges
Europhysics Letters (EPL), 2005Co-Authors: Valeriy Lisovskiy, Jean-paul Booth, S. Martins, K. Landry, D. Douai, V. CassagneAbstract:Breakdown and extinction curves have been measured for RF capacitive Low-Pressure discharges in nitrogen and hydrogen at a frequency of 13.56 MHz and discharge gaps between 6 and 25 mm. In particular, the Low-Pressure, high-voltage region of the extinction curves is reported for the first time. The shape of the extinction curves was found to be similar to that of the breakdown curves. At sufficiently large gaps (L > 10 mm) the RF extinction voltage was found to be multi-valued in the Low-Pressure region, as is observed for the breakdown voltage. In this region, extinction can occur when the voltage is increased because the width of the two sheaths occupies the whole discharge space.
Peter Hodgson - One of the best experts on this subject based on the ideXlab platform.
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buckling in Low Pressure tube hydroforming
Journal of Manufacturing Processes, 2017Co-Authors: Chetan P. Nikhare, Matthias Weiss, Peter HodgsonAbstract:Abstract Tube hydroforming is an innovative forming process in which the tube is pressurized by a fluid medium and formed into a complex shape. There are two types, Low and high Pressure hydroforming. In the high Pressure process, the tube is expanded by an internal Pressure to fill the die cavity. In the Low Pressure approach a constant Pressure is maintained inside the tube which is crushed to shape by the action of a punch or an upper die movement. It is known that in Low Pressure hydroforming the required Pressure and die closing force are much Lower compared to the high Pressure process. Implementation of advanced high strength steel tubes in tube hydroforming is a promising way to Lower weight by reducing the material thickness. Using high strength materials increases buckling tendency in Low Pressure tube hydroforming. In the current study, a method using a plastic energy principle is proposed for estimating the minimum Pressure required for the Low Pressure hydroforming of a buckle free component. The present investigation addresses the side wall of the tube as a vertical column pinned at each end. The proposed model shows that the method can predict the minimum Pressure required with sufficient accuracy. The model also reveals that the minimum Pressure required depends on the yield stress of the tube material, the tube material thickness and the straight length of the tube section that is in contact with the die. Applying sensitivity analysis it is determined that the required Pressure is strongly affected by the yield stress of the tube material.
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Die closing force in Low Pressure tube hydroforming
Journal of Materials Processing Technology, 2010Co-Authors: Chetan P. Nikhare, Matthias Weiss, Peter HodgsonAbstract:Recently, Low Pressure tube hydroforming has emerged as a technology to reduce the weight of automotive body structures by alLowing the implementation of advanced high strength steels and minimizing the number of process steps. In this study, a simplified analytical model based on a rigid, perfectly plastic material model was developed to determine the die closing force needed to form a simple geometry using the Low Pressure hydroforming process. The analytical solution developed was compared with experimental and numerical results; this demonstrated a reasonable accuracy of the model which will assist in the understanding of the basic principles governing the Low Pressure hydroforming process.
Hong H. Lee - One of the best experts on this subject based on the ideXlab platform.
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Low-Pressure nanoimprint lithography
Nano Letters, 2004Co-Authors: Dahl-young Khang, Hyewon Kang, Tae-il Kim, Hong H. LeeAbstract:A Low Pressure (2similar to3 bar) nanoimprint lithography technique is developed that utilizes a thin fluoropolymer film (similar to100 mum) mold. The flexible film mold alLows imprinting of submicron pattern features at such a Low Pressure primarily due to "sequential" imprinting made possible by the mold flexibility and the conformal contact made between the film mold and the substrate. The surface energy of the fluoropolymer mold material is Low enough that no mold surface treatment is needed for clean demolding. Easy replication of the film mold by a simple solvent casting is another advantage of the proposed method. Also the nanoscale (
Hyun Jung Lee - One of the best experts on this subject based on the ideXlab platform.
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Low Pressure nanoimprint lithography
Nano Letters, 2004Co-Authors: Dahl-young Khang, Hyewon Kang, Tae-il Kim, Hyun Jung LeeAbstract:A Low Pressure (2∼3 bar) nanoimprint lithography technique is developed that utilizes a thin fluoropolymer film (∼100 μm) mold. The flexible film mold alLows imprinting of submicron pattern features at such a Low Pressure primarily due to “sequential” imprinting made possible by the mold flexibility and the conformal contact made between the film mold and the substrate. The surface energy of the fluoropolymer mold material is Low enough that no mold surface treatment is needed for clean demolding. Easy replication of the film mold by a simple solvent casting is another advantage of the proposed method. Also the nanoscale (<100 nm) replication capability is demonstrated and discussed with a solvent-cast thin film fluoropolymer mold.
