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用X射线反射方法研究了分子束外延技术生长的Si中Ge薄层异质结构的Ge原子分布特性.根据X射线反射理论及Parratt数值计算方法对实验反射曲线的模拟,得到不同厚度的Ge薄层异质结构样品中Ge原子的深度分布为非对称指数形式:在靠近样品表面一侧的衰减长度为8埃,而在靠近样品衬底一侧的衰减长度为3埃,且分布形式与Ge原子层的厚度无关。讨论了不同结构参数(Ge原子薄层的深度、Ce原子分布范围、样品表面粗糙度、样品表面氧化层厚度等)对样品低角反射曲线的影响. 相似文献
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用X射线反射方法研究了分子束外延技术生长的Si中Ge薄层异质结构的Ge原子分布特性.根据X射线反射理论及Parratt数值计算方法对实验反射曲线的模拟,得到不同厚度的Ge薄层异质结构样品中Ge原子的深度分布为非对称指数形式:在靠近样品表面一侧的衰减长度为8埃,而在靠近样品衬底一侧的衰减长度为3埃,且分布形式与Ge原子层的厚度无关.讨论了不同结构参数(Ge原子薄层的深度、Ge原子分布范围、样品表面粗糙度、样品表面氧化层厚度等)对样品低角反射曲线的影响. 相似文献
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本题分为四个部分: A部分进行光与样品的准直,B部分测量样品中微球间距以及微球直径,C部分测量样品中矩形网格阵列的矩形结构尺寸和取向角,D部分测量样品网格间距,E部分对C和D测量到的矩形网格阵列形貌进行图形化。本文在官方提供的参考答案基础上,给出详尽的解答过程与注意事项,对考察要点与评分标准进行分析。 相似文献
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本文讨论了半旋转椭球聚光罩的聚焦与放大作用。结合R943-02型光电倍增管接收器及平面型发光样品,给出了聚光罩参数的选择方法,计算了最佳参数及相应的聚光效率 相似文献
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本采用Newton迭代法解决了无限长各向异性HTSC导线临界电流密度的自场效应,设临界电流密度平行于x轴,外场与y轴成θ角。我们给出了零外场下,临界电流密度及其自场的空间分布,计算了平均临界电流密度与θ角和外场数值的关系,发现并讨论了自场尺寸效应中的极值问题。我们的方法将可以有效地推广到其他更复杂形状和性质的样品中。 相似文献
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利用醋酸锌[Zn(CH3COO)2·2H2O]和六次甲基四胺(C6H12N4)以一定比例配置成反应溶液,通过水热合成法制备了六角锥状ZnO纳米结构。同时,使用了扫描电子显微镜(SEM)、X射线衍射和选区电子衍射(SAED),对样品的形貌与结构进行了分析。结果表明,样品形貌成六角锥状结构,并且在[002]方向择优生长。通过对样品的光学性能测试,由PL光谱分析可知,样品在379nm处有一个较强的紫外发光峰,并且在可见光区域产生了一些较弱的可见光发射峰,表明制备的六角锥状ZnO纳米结构的晶体质量不是很好。除此之外,对六角锥状ZnO的生长机理也进行了讨论。 相似文献
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V. V. Rocheva E. V. Khaydukov O. A. Novodvorsky O. D. Khramova V. Ya. Panchenko 《Laser Physics》2011,21(3):624-629
The research of the 119Sn thin films growth on amorphous Si that is important for the multilayer periodical spin-tunnel nanostructures creation have
been investigated in this paper. The 119Sn mono-isotopic thin films on the silicon substrates (100) had been received by crossed-beam pulsed laser deposition method
(CBPLD). Similarly the [Fe/Si/Sn/Si] multilayer periodical structures have been deposited. The received samples were investigated
by atomic-force microscopy, electronic microscopy and X-ray reflectometry methods. It has been established that at 119Sn film thickness up to 3 nm it is possible to received atomic-smooth surfaces with 0.5 nm roughness. 相似文献
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介绍了X射线宽带多层膜材料W和B4C的选定方法,依据伯宁(BERNING)公式确定出了在0.154 nm处X射线宽带多层膜的最佳膜对数。引入适当的评价函数,利用具有全局寻优特性且效率较高的遗传算法,在波长0.154 nm处优化设计出了掠入射角(θ)0.5°~0.9°范围内反射率值达到40%的宽角度宽带多层膜。宽带多层膜反射镜采用磁控溅射方法制备,并用X射线衍射仪对样品进行了检测,结果表明在掠入射角(2θ)1.0°~1.8°之间的相对反射率光谱曲线比较平坦。 相似文献
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为研制极紫外波段窄带多层膜反射镜,采用低原子序数材料组合设计了30.4 nm波长处Mg/SiC,Si/SiC,Si/B4C和Si/C多层膜反射镜,并与极紫外波段传统的Mo/Si多层膜反射镜进行对比。采用直流磁控溅射技术制备了这些多层膜,在国家同步辐射实验室辐射与计量光束线完成了多层膜反射率测量,测量结果表明:Mg/SiC多层膜的带宽最小,为1.44 nm,且反射率最高,为44%;而Mo/Si多层膜的反射率仅为24%,带宽为3.11 nm。实验结果证明了采用低原子序数材料组成的多层膜的带宽要比常规多层膜窄,该方法可以应用于极紫外波段高分辨研究。 相似文献
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为研制极紫外波段窄带多层膜反射镜,采用低原子序数材料组合设计了30.4 nm波长处Mg/SiC,Si/SiC,Si/B4C和Si/C多层膜反射镜,并与极紫外波段传统的Mo/Si多层膜反射镜进行对比。采用直流磁控溅射技术制备了这些多层膜,在国家同步辐射实验室辐射与计量光束线完成了多层膜反射率测量,测量结果表明:Mg/SiC多层膜的带宽最小,为1.44 nm,且反射率最高,为44%;而Mo/Si多层膜的反射率仅为24%,带宽为3.11 nm。实验结果证明了采用低原子序数材料组成的多层膜的带宽要比常规多层膜窄,该方法可以应用于极紫外波段高分辨研究。 相似文献
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为了满足类氖-锗X射线激光研究的需要,设计制备了23.4 nm软X射线多层膜反射镜.依据多层膜选材原则并考虑材料的物理化学特性选择新的材料Ti与Si组成材料对.设计优化材料多层膜的周期厚度(d),材料比例(Γ),周期数(N),计算出Ti/Si反射率曲线.通过实验优化各种镀膜工艺参数,制备出了23.4 nm的Ti/Si多... 相似文献
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J. Gautier F. Delmotte F. Bridou M.F. Ravet F. Varniere M. Roulliay A. Jerome I. Vickridge 《Applied Physics A: Materials Science & Processing》2007,88(4):719-725
Scandium/silicon multilayers have been deposited by magnetron sputtering and characterized by several techniques. Experimental
peak reflectances of 0.22 and 0.37 have been measured respectively at wavelengths of 40 nm and 46 nm, for 10° incidence angle.
The corresponding theoretical values for a perfect Sc/Si structure are respectively 0.38 and 0.57. In order to explain these
differences between calculated and measured reflectivity, thin film and multilayer characterizations have been done. Effects
of multilayer imperfections on the reflectivity have been estimated independently by means of simulation. Based on these results,
a new design of Sc/Si multilayer is proposed with top layer thickness optimization. With this design, the experimental peak
reflectance reaches 0.46 at a wavelength of 46 nm.
PACS 78.67.Pt; 78.66.-W; 81.15.Cd 相似文献
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Cheng Yang Yan Hu Ruiqi Shen Yinghua Ye Shouxu Wang Tianli Hua 《Applied Physics A: Materials Science & Processing》2014,114(2):459-464
Al/Ni multilayer bridge films, which were composed of alternate Al and Ni layers with bilayer thicknesses of 50, 100 and 200 nm, were prepared by RF magnetron sputtering. In each bilayer, the thickness ratio of Al to Ni was maintained at 3:2 to obtain an overall 1:1 atomic composition. The total thickness of Al/Ni multilayer films was 2 μm. XRD measurements show that the compound of AlNi is the final product of the exothermic reactions. DSC curves show that the values of heat release in Al/Ni multilayer films with bilayer thicknesses of 50, 100 and 200 nm are 389.43, 396.69 and 409.92 J?g?1, respectively. The temperatures of Al/Ni multilayer films were obviously higher than those of Al bridge film and Ni bridge film. Al/Ni multilayer films with modulation of 50 nm had the highest electrical explosion temperature of 7000 K. The exothermic reaction in Al/Ni multilayer films leads to a more intense electric explosion. Al/Ni multilayer bridge films with modulation period of 50 nm explode more rapidly and intensely than other bridge films because decreasing the bilayer thickness results in an increased reaction velocity. 相似文献
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Nanometer scale Al/AlN multilayers have been prepared by dc magnetron sputtering technique with a columnar target. A set of Al/AlN multilayers with the Al layer thickness of 2.9 nm and the AlN layer thickness variation from 1.13 to 6.81 nm were determined. Low angle X-ray diffraction (LAXRD) was used to analyze the layered structure of multilayers. The phase structure of the coatings was investigated with grazing angle XRD (GAXRD). Mechanical properties of these multilayers were thoroughly studied using a nanoindentation and ball-on-disk micro-tribometer. It was found that the multilayer hardness and reduced modulus showed no strong dependence on the AlN layer thickness. Al2.9 nm/AlN1.13 nm multilayer had more excellent tribological properties than single layers and other proportion multilayers with a lowest friction coefficient of 0.15. And the tribological properties of all the multilayers are superior to the AlN single layer. 相似文献
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研究了极紫外波段的双功能光学元件。采用周期膜叠加的思想,运用遗传方法优化设计了在19.5 nm处高反,在30.4 nm处抑制的双功能多层膜。采用磁控溅射技术制备了多层膜,利用X射线衍射仪测试了多层膜的结构,在国家同步辐射实验室测试了双功能多层膜的反射特性。结果表明:制备出的双功能膜性能与设计相符,在入射角13°,19.5 nm处的反射率达到33.3%,接近传统的19.5 nm周期高反膜的反射率,并且在30.4 nm附近将反射率由1.1%降到9.6×10-4。 相似文献