8 resultados para 150-906

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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Recently, the size dependence of mechanical behaviors, particularly the yield strength and plastic deformation mode, of bulk metallic glasses (BMG) has created a great deal of interest. Contradicting conclusions have been drawn by different research groups, based on various experiments on different BMG systems. Based on in situ compression transmission electron microscopy (TEM) experiments on Zr41Ti14Cu12.5Ni10Be22.5 (Vit 1) nanopillars, this paper provides strong evidence that shear banding still prevails at specimen length scales as small as 150 nm in diameter. This is supported by in situ and ex situ images of shear bands, and by the carefully recorded displacement bursts under load control its well as load drops under displacement control. Finite element modeling of the stress state within the pillar shows that the unavoidable geometry constraints accompanying such experiments impart a strong effect on the experimental results, including non-uniform stress distributions and high level hydrostatic pressures. The seemingly improved compressive ductility is believed to be due to such geometry constraints. Observations underscore the notion that the mechanical behavior of metallic glasses, including strength and plastic deformation mode, is size independent at least in Vit 1. (C) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

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报道了Φ150mm CMOS硅外延材料的研究开发及集成电路应用成果,对Φ200mmP/P~-硅外延材料进行了初步探索研究。Φ150mm P/P~+硅外延片实现了批量生产,并成功应用于集成电路生产线,芯片成品率大于80%。硅外延片的参数指标能满足集成电路制造要求。

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随着大规模和超大规模集成电路特征尺寸向亚微米、深亚微米发展,下一代集成电路对硅片的表面晶体完整性和电学性能提出了更高的要求。与含有高密度晶体原生缺陷的硅抛光片相比,硅外延片一般能满足这些要求。该文报道了应用于先进集成电路的150mmP/P~+ CMOS硅外延片研究进展。在PE2061硅外延炉上进行了P/P~+硅外延生长。外延片特征参数,如外延层厚度、电阻率均匀性,过渡区宽度及少子产生寿命进行了详细表征。研究表明:150mm P/P~+CMOS硅外延片能够满足先进集成电路对材料更高要求。

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This paper reports that the transmission of O6+ ions with energy of 150keV through capillaries in an uncoated Al2O3 membrane was measured, and agreements with previously reported results in general angular distribution of the transmitted ions and the transmission fractions as a function of the tilt angle well fitted to Gaussian-like functions were observed. Due to using an uncoated capillary membrane, our c is larger than that using a gold-coated one with a smaller value of E-p/q, which suggests a larger equilibrium charge Q(infinity) in our experiment. The observed special width variation with time and a larger width than that using a smaller E-p/q were qualitatively explained by using mean-field classical transport theory based on a classical-trajectory Monte Carlo simulation.

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对北京春季6种物候的计算得出其代表性指标—山桃始花期,并分析物候对气温变化的响应模式。根据气温变化态势,将历史时期气温和物候资料划分为4个时间段,并采用u检验论证时间段间具有显著性差异,分析物候期对气温变化的响应模式和机制,得出:物候期的提前与推迟对温度的增高与降低的响应是非线性的,在同等增、降温幅度下,因降温而导致的物候期推迟幅度较因增温而导致物候期提前幅度小;平均气温增高1℃,北京春季物候期提前2.8~3.6d。并估算了未来北京春季物候变化趋势。