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81.
提出了一种低温金属单向诱导横向晶化的多晶硅薄膜晶体管(LT-MIUC poly-Si TFT) 的技术 . 使用该技术可在大面积廉价玻璃衬底上制备出高迁移率、低漏电电流、具有较好均匀性的 多晶硅器件. 在进一步的研究中,设计了一种新型的栅控轻掺杂漏区(GM-LDD)结构,有效地 解决了在较高源漏电压下的栅诱导漏电问题. 使得LT-MIUC poly-Si TFT 更适用于高质量的 有源矩阵显示器.
关键词:
金属单向诱导横向晶化
多晶硅薄膜晶体管
新型栅控轻掺杂漏区结构 相似文献
82.
用双靶磁控溅射的方法在玻璃衬底上制备了Cu11In9合金薄膜,然后将Cu11In9合金薄膜封闭在石墨盒中进行真空硒化退火得到CuInSe2薄膜.用扫描电子显微镜(SEM)和X射线粉末衍射(XRD)对CuInSe2薄膜进行了表征,结果表明CuInSe2薄膜具有单一的晶相,均匀、致密的结构,以及粒径超过了3μm的晶粒.
关键词:
铜铟硒多晶薄膜
磁控溅射
真空硒化
太阳能电池 相似文献
83.
Luca Placidi Kolumban Hutter 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2005,57(1):160-181
New and explicit anisotropic constitutive equations between the stretching and deviatoric stress tensors for the two- and
three-dimensional cases of incompressible polycrystalline materials are presented. The anisotropy is assumed to be driven
by an Orientation Distribution Function (ODF). The polycrystal is composed of transversally isotropic crystallites, the lattice
orientation of which can be characterized by a single unit vector. The proposed constitutive equations are valid for any frame
of reference and for every state of deformation. The basic assumption of this method is that the principle directions of the
stretching and of the stress deviator are the same in the isotropic as well as in the anisotropic case. This means that the
proposed constitutive laws are able to model the effects of anisotropy only via a change of the fluidity due to a change of
the ODF. Such an assumption is justified to guarantee that, besides knowledge of the parameters involved in the isotropic
constitutive equation, the anisotropic material response is completely characterized by only one additional parameter, a type
of enhancement factor. Explicit comparisons with experimental data are conducted for Ih–ice.
Dedicated to Prof. L.W. Morland on the occasion of his 70th birthday
Received: July 6, 2004; revised: November 8, 2004 相似文献
84.
Paweł Sobieszczyk Aleksandra Pajzderska Dominika Kuźma Marcin Majka Piotr Zieliński 《Phase Transitions》2016,89(4):425-435
The surface acoustic waves in empty cylindrical pores in the amorphous silica MCM-41 as well as in the same pores partially filled with water are studied with the use of a continuum model. The model is shown to be adequate to predict dispersion relations, cut-off wave vectors and the Airy phases for the secular surface waves of the lowest azimuthal indices n. Quantitative predictions are presented both in the liquid and in the polycrystalline solid phase of water. Two sagittal surface waves exist when water is in the liquid phase. The phase transition to the solid phase (ice) results in the disappearance of the high-frequency mode. All the effects occur in the Terahertz frequency region. 相似文献
85.
Fabrication of polycrystalline silicon films by Al‐induced crystallization of silicon‐rich oxide films 下载免费PDF全文
Jong‐Hwan Yoon 《固体物理学:研究快报》2016,10(9):668-672
Polycrystalline silicon (poly‐Si) films were fabricated by aluminum (Al)‐induced crystallization of Si‐rich oxide (SiOx) films. The fabrication was achieved by thermal annealing of SiOx /Al bilayers below the eutectic temperature of the Al–Si alloy. The poly‐Si film resulting from SiO1.45 exhibited good crystallinity with highly preferential (111) orientation, as deduced from Raman scattering, X‐ray diffraction, and transmission electron microscopy measurements. The poly‐Si film is probably formed by the Al‐induced layer exchange mechanism, which is mediated by Al oxide. 相似文献
86.
实验中纳米压痕被广泛用于测量单晶或多晶石墨烯的力学性质,而分子动力学模拟中研究者们更多地使用单轴拉伸来测量石墨烯的力学性质.两种测量方法对于多晶石墨烯弹性模量和破坏强度的预测是否存在差异?多晶石墨烯的力学性质是否依赖于其晶粒大小?对于固定晶粒大小的多晶石墨烯,拓扑结构的不同是否影响其力学性质?围绕以上问题,通过对比纳米压痕和单轴拉伸两种方法的分子动力学模拟,研究了多晶石墨烯弹性模量和破坏强度对晶粒尺寸、拓扑结构和测量方法的依赖性. 相似文献
87.
Xiang Xu Peter Binkele Wolfgang Verestek Siegfried Schmauder 《Molecules (Basel, Switzerland)》2021,26(9)
As Nickel (Ni) is the base of important Ni-based superalloys for high-temperature applications, it is important to determine the creep behavior of its nano-polycrystals. The nano-tensile properties and creep behavior of nickel polycrystalline nanopillars are investigated employing molecular dynamics simulations under different temperatures, stresses, and grain sizes. The mechanisms behind the creep behavior are analyzed in detail by calculating the stress exponents, grain boundary exponents, and activation energies. The novel results in this work are summarized in a deformation mechanism map and are in good agreement with Ashby’s experimental results for pure Ni. Through the deformation diagram, dislocation creep dominates the creep process when applying a high stress, while grain boundary sliding prevails at lower stress levels. These two mechanisms could also be coupled together for a low-stress but a high-temperature creep simulation. In this work, the dislocation creep is clearly observed and discussed in detail. Through analyzing the activation energies, vacancy diffusion begins to play an important role in enhancing the grain boundary creep in the creep process when the temperature is above 1000 K. 相似文献
88.
To extract quantitative and meaningful relationships between material microstructure and deformation twinning in magnesium, we conduct a statistical analysis on large data sets generated by electron backscattering diffraction (EBSD). The analyses show that not all grains of similar orientation and grain size form twins, and twinning does not occur exclusively in grains with high twin Schmid factors or in the relatively large grains of the sample. The number of twins per twinned grain increases with grain area, but twin thickness and the fraction of grains with at least one visible twin are independent of grain area. On the other hand, an analysis of twin pairs joined at a boundary indicates that grain boundary misorientation angle strongly influences twin nucleation and growth. These results question the use of deterministic rules for twin nucleation and Hall–Petch laws for size effects on twinning. Instead, they encourage an examination of the defect structures of grain boundaries and their role in twin nucleation and growth. 相似文献
89.
We present a three-dimensional model of intergranular hydrogen-embrittlement (HE) that accounts for: (i) the degradation of grain-boundary strength that arises from hydrogen coverage; (ii) grain-boundary diffusion of hydrogen; and (iii) a continuum model of plastic deformation that explicitly resolves the three-dimensional polycrystalline structure of the material. The polycrystalline structure of the specimen along the crack propagation path is resolved explicitly by the computational mesh. The texture of the polycrystal is assumed to be random and the grains are elastically anisotropic and deform plastically by crystallographic slip. We use the impurity-dependent cohesive model in order to account for the embrittling of grain boundaries due to hydrogen coverage. We have carried out three-dimensional finite-element calculations of crack-growth initiation and propagation in AISI 4340 steel double-cantilever specimens in contact with an aggressive environment and compared the predicted initiation times and crack-growth curves with the experimental data. The calculated crack-growth curves exhibit a number of qualitative features that are in keeping with observation, including: an incubation time followed by a well-defined crack-growth initiation transition for sufficiently large loading; the existence of a threshold intensity factor K Iscc below which there is no crack propagation; a subsequent steeply rising part of the curve known as stage I; a plateau, or stage II, characterized by a load-insensitive crack-growth rate; and a limiting stress-intensity factor K Ic , or toughness, at which pure mechanical failure occurs. The calculated dependence of the crack-growth initiation time on applied stress-intensity factor exhibits power-law behavior and the corresponding characteristic exponents are in the ball-park of experimental observation. The stage-II calculated crack-growth rates are in good overall agreement with experimental measurements. 相似文献
90.
A phase-field model for modeling the diffusional processes in an elastically anisotropic polycrystalline binary solid solution is described. The elastic interactions due to coherency elastic strain are incorporated by solving the mechanical equilibrium equation using an iterative-perturbation scheme taking into account elastic modulus inhomogeneity stemming from different grain orientations. We studied the precipitate interactions among precipitates across a grain boundary and grain boundary segregation–precipitate interactions. It was shown that the local pressure field from one coherent precipitate influences the shape of precipitates in other grains. The local pressure distribution due to primary coherent precipitates near the grain boundary leads to inhomogeneous solute distribution along the grain boundary, resulting in non-uniform distribution of secondary nuclei at the grain boundary. 相似文献