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51.
In this study, after Dill’s model is discussed for transmittance and refractive indices of the non-chemically amplified resists, G- and I-line novolak resists, and the chemically amplified resists, a modification of Dill’s model as a new exposure model is introduced. The simulation results obtained using this new model with the multi-thin film interface method and the Berning theory have shown a good matching to the experimental data. Also, the simulated transmittance change due to the exposure parameters are used to analyze the influence of the coefficients on the transmittance. 相似文献
52.
As they are first optimized for their ion losses,ECRISs are always under a fundamental compromise: having high losses and strong confinement at the same time.To help ECR ion source developers in the design or improvement of existing machines,general comments are presented in a review article being soon published. In this 160 pages contribution,fundamental aspects of ECRISs are presented,with a discussion of electron temperature and confinement and ion confinement.Then,as microwaves play a key role in these machines, a chapter presents major guidelines for microwave launching and coupling to ECR plasma.Moreover,once ECR plasma is created,understanding this plasma is important in ion sourcery;and a section is dedicated to plasma diagnostics with an emphasis on the determination of electron and ion density and temperature by vacuum ultraviolet(VUV)spectroscopy.Another chapter deals with the role of magnetic confinement and presents updated scaling laws.Next chapter presents different types of ECRISs designed according to the main parameters previously described.Finally,some industrial applications of ECRISs and ECR plasmas in general are presented like ion implantation and photon lithography.Some hints taken from this review article are presented in the following article. 相似文献
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This paper presents a modified descent method for solving co-coercive variational inequalities. Incorporating with the techniques of identifying descent directions and optimal step sizes along these directions, the new method improves the efficiencies of some existing projection methods. Some numerical results for an economic equilibrium problem are reported. 相似文献
55.
Tin oxalate as a precursor of tin dioxide and electrode materials for lithium-ion batteries 总被引:2,自引:0,他引:2
R. Alcántara Fernández F. Madrigal P. Lavela C. Pérez-Vicente J. Tirado 《Journal of Solid State Electrochemistry》2001,6(1):55-62
Tin(II) oxalate was studied as a novel precursor for active electrode materials in lithium-ion batteries. The discharge of
lithium cells using tin oxalate electrodes takes place by three irreversible steps: tin reduction, forming a lithium oxalate
matrix; solvent decomposition to form a passivating layer; and oxalate reduction in a two-electron process. These are followed
by reversible alloying of tin with lithium, leading to a maximum discharge of 11 F/mol. Cycling of the cells showed reversible
capacities higher than 600 mAh/g during the first five cycles and ca. 200 mAh/g after 50 cycles. Tin oxalate was converted
to tin dioxide by thermal decomposition at 450 °C and also by a chemical method by dissolving tin oxalate powder in 33% v/v
hydrogen peroxide at room temperature. The ultrafine nature of the tin dioxide powders obtained by this procedure allow their
use as electrodes in lithium cells. The best capacity retention during the first five cycles was achieved for a sample heat
treated to 250 °C to eliminate surface water.
Electronic Publication 相似文献
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J. Ledieu R. McGrath Q. Chen T.A. Lograsso K.J. Caspersen B. Unal P.A. Thiel 《Surface science》2005,583(1):4-15
We compare step morphologies on surfaces of Al-rich metallic alloys, both quasicrystalline and crystalline. We present evidence that the large-scale step structure observed on Al-rich quasicrystals after quenching to room temperature reflects equilibrium structure at an elevated temperature. These steps are relatively rough, i.e., have high diffusivity, compared to those on crystalline surfaces. For the fivefold quasicrystal surface, step diffusivity increases as step height decreases, but this trend is not obeyed in a broader comparison between quasicrystals and crystals. On a shorter scale, the steps on Al-rich alloys tend to exhibit local facets (short linear segments), with different facet lengths, a feature which could develop during quenching to room temperature. Facets are shortest and most difficult to identify for the fivefold quasicrystal surface. 相似文献
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S. A. Sánchez J. González‐García M. D. Esclapez M. I. Díez‐García J. F. Del Río J. L. Gazapo 《Surface and interface analysis : SIA》2010,42(4):311-315
Electrograining of aluminium in hydrochloric acid is one of the most commonly used processes for manufacturing printing lithographic plates. Two of the main features to be taken into account are the final morphology of the electrograined surface and the susceptibility of the alloy to be processed or, more specifically, the speed of the processing line. Both issues determine the efficiency of the production in terms of quality and time. In this work, a widely used commercial aluminium alloy (1050) is compared with a new experimental one (1050 modified with Zn) and with a higher strength alloy (namely 1020). In order to analyse their response to a.c. graining in HCl for high‐speed lines, some techniques such as image analysis or interferometry have been used. In general, the alloys doped with Zn and Mg present a better response to litho processing in terms of graining activity and reduction of streakiness when treatment of lower time periods is applied due to their influence as pitting initiators. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献