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991.
Ralf Endres Tillmann KraussFrank Wessely Udo Schwalke 《Microelectronic Engineering》2011,88(12):3393-3398
In this work, we present MOS capacitors and field effect transistors with a crystalline gadolinium oxide (Gd2O3) gate dielectric and metal gate electrode (titanium nitride) fabricated in a gentle damascene gate last process. Details of the gate last process and initial results on MOS devices with equivalent oxide thicknesses (EOT) of 3.0 nm and 1.5 nm, respectively, are shown. 相似文献
992.
Qingqing Chen Daxin Li Zhihua Yang Dechang Jia Yu Zhou Ralf Riedel 《Ceramics International》2021,47(16):22839-22853
Tris(dichloromethylsilylethyl)borane is a compound containing a B–C bond and Cl and H elements. Herein, we propose a novel method to synthesize polyborosilazanes using tris(dichloromethylsilylethyl)borane and boron trichlorosilane as boron sources and hexamethyldisilazane as a nitrogen source. The microstructure and chemical composition of the as-synthesized polyborosilazanes and as-annealed SiBCN ceramics were investigated using Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, Raman spectroscopy, scanning electron microscope, and transmission electron microscope methods. The organic precursors were converted entirely into inorganic ceramics at 800 °C, and the ceramic yield of the polyborosilazanes was 88% at 1000 °C. SiBCN ceramics with irregular shapes contained chemical bonds of B–N, Si–N, and Si–C at 1500 °C and retained an amorphous structure below 1600 °C. After the first cycle, the fabricated SiBCN ceramic anodes exhibited a reversible capacity of 261.3 mA h/g, which was 2.6 times that reported in the literature (101 mA h/g). The discharge capacity decreased to 157.6 mA h/g after 30 cycles. The satisfactory electrochemical performance of the resulting SiBCN ceramic anodes can be attributed to the formation of conductive carbon species favoring the transport properties of lithium ion. 相似文献
993.
Viatcheslav Malikov Ralf Ossenbrink Bernd Viehweger Vesselin Michailov 《The International Journal of Advanced Manufacturing Technology》2012,61(5-8):449-455
The nonparametric location–scale statistic is introduced for a change-point problem. A combination of the Wilcoxon and Mood statistics is extended to the change-point setting. The limiting distribution of proposed statistic is derived for testing the null hypothesis of no change. The finite sample critical value of the suggested statistic is estimated by simulation studies. The accuracy of detecting a change point is investigated by simulation studies for various distributions. The method is illustrated by the analysis of real data. 相似文献
994.
Schäffer Michael Sturm Ralf Friedrich Horst E. 《International Journal of Mechanics and Materials in Design》2019,15(1):43-60
International Journal of Mechanics and Materials in Design - A challenge in the design and optimization of vehicle structures is the high computational costs required for crash analysis. In this... 相似文献
995.
Sheng Naicheng Horke Katharina Meyer Andreas Rettig Ralf Singer Robert F. 《Oxidation of Metals》2019,91(1-2):113-129
Oxidation of Metals - The oxidation behavior of superalloy IN 713 fabricated by metal injection molding (MIM) was investigated and compared with standard cast material plus hot isostatic pressing... 相似文献
996.
997.
Philipp Mertmann Denis Eremin Thomas Mussenbrock Ralf Peter Brinkmann Peter Awakowicz 《Computer Physics Communications》2011,(10):2161-2167
Particle-in-cell (PIC) simulations with Monte-Carlo collisions are used in plasma science to explore a variety of kinetic effects. One major problem is the long run-time of such simulations. Even on modern computer systems, PIC codes take a considerable amount of time for convergence. Most of the computations can be massively parallelized, since particles behave independently of each other within one time step. Current graphics processing units (GPUs) offer an attractive means for execution of the parallelized code. In this contribution we show a one-dimensional PIC code running on NVIDIA® GPUs using the CUDA™ environment. A distinctive feature of the code is that size of the cells that the code uses to sort the particles with respect to their coordinates is comparable to size of the grid cells used for discretization of the electric field. Hence, we call the corresponding algorithm “fine-sorting”. Implementation details and optimization of the code are discussed and the speed-up compared to classical CPU approaches is computed. 相似文献
998.
Dr. Frank Wendland Dr. Georg Berthold Dr. Johann-Gerhard Fritsche Dr. Frank Herrmann Dr. Ralf Kunkel Prof.?Dr. Hans-J��rgen Voigt Prof.?Dr. Harry Vereecken 《Grundwasser》2011,16(3):163-176
A regional scale conceptual hydrogeological model has been developed for evaluating residence times of groundwater in the upper aquifers and unsaturated zone within the Federal State of Hessen (Germany). The model is based on digitally available data bases and was applied with a spatial resolution of 60?m×60?m. Typical residence times for areas of unconsolidated deposits ranged between 10 and 25 years, whereas residence times of less than 5?years were found in areas of consolidated rock. Within the EU-Water Framework Directive, these results may help in assessing temporal and regional impacts of measures to reduce mass loading from the surface to groundwater. This will lead to better decisions, for instance whether additional measures to reach the environmental objectives should be applied. 相似文献
999.
Andreas Mutzke Ivan Bizyukov Ralf SchneiderJames Davis 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2011,269(6):582-589
In this work, a Si pitch grating with typical lateral dimensions of 200-250 nm was exposed to 6 keV C+ ions at normal incidence and at an angle of 42° both parallel and perpendicular to the grating structure. In contrast to volatile and recycling ions (like Ar+ or H+), non-recycling ions are able to modify the surface not only due to sputtering, but also due to implantation of incident ions and the re-deposition of projectile atoms following sputtering or reflection. The target-projectile combination used in this work is an example of such a system forming a mixed Si-C surface. The interaction between the ion beam and the surface has been studied both experimentally and numerically with the focus on validation of the numerical model of the newly developed SDTrimSP-2D code. SDTrimSP-2D is capable of following the evolution of the Si-C system including ion-surface interactions with 2D micro- and nano-structured surfaces. The SDTrimSP-2D code takes the interdependency of surface morphology, sputtering and implantation into account. The simulated surface morphology has been compared to cross-sections of bombarded Si pitch grating obtained by SEM, revealing good agreement between experiment and simulation. The calculations also provide improved insight into the mechanisms of surface modification by sputtering, implantation and material transport by redeposition. 相似文献
1000.
Martin Rinker Marianne John Pierre C. Zahlen Ralf Schäuble 《Engineering Fracture Mechanics》2011,78(17):2835-2847
The face sheet debonding behaviour under quasi-static and fatigue loading in sandwich structures consisting of Carbon Fibre Reinforced Polymer face sheets and a Polymethacrylimid foam core is investigated. The sandwich structure is tested under global mode I and global mode II loading using the Single Cantilever Beam test and the Cracked Sandwich Beam test. Because of the different thermal expansion behaviour of the face sheets and the foam core thermal stresses occur already after the manufacturing process. The impact of these temperature loads on the crack propagation behaviour is investigated via evaluating the experiments numerically with Finite Element Analysis and Virtual Crack Closure Technique. 相似文献