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991.
We examined the thermal stability of amorphous silicon oxycarbide (SiOC) and crystalline Fe composite by in situ and ex situ annealing. The Fe/SiOC multilayer thin films were grown via magnetron sputtering with controlled length scales on a surface-oxidized Si (100) substrate. These Fe/SiOC multilayers were in situ or ex situ annealed at temperature of 600 °C or lower. The thin multilayer sample (~10 nm) was observed to have a layer breakdown after 600 °C annealing. Diffusion starts from low groove angle triple junctions in Fe layers. In contrast, the thick multilayer structure (~70 nm) was found to be stable and an intermixed layer (FexSiyOz) was observed after 600 °C annealing. The thickness of the intermixed layer does not vary as annealing time goes up. The results suggest that the FexSiyOz layer can impede further Fe, Si and O diffusion, and assists in maintaining morphological stability. 相似文献
992.
Partially oxidized free-standing porous silicon films show a strongly superlinear increase in photoluminescence (PL) intensity above a threshold cw excitation intensity of 10 W/cm2. The PL-intensity increase can be expressed by a power law with n9 as a function of the excitation intensity. The PL-peak wavelength of this emission is slightly redshifted from that at low-excitation levels. These changes are fully reversible and reproducible, but not observed in samples on substrate. We attribute this behavior to thermal reexcitation of carriers trapped at the dangling bond states in initially nonluminescent Si nanocrystallites. 相似文献
993.
994.
基于k·p微扰法计算了单轴〈111〉应力作用下硅的价带结构, 并与未受应力时体硅的价带结构进行了比较. 给出了单轴〈111〉应力作用下硅价带顶处能级的移动、分裂以及空穴有效质量的变化情况. 计算所得未受应力作用时硅价带顶处重空穴带、轻空穴带有效质量与相关文献报道体硅有效质量结果一致. 拓展了单轴应力硅器件导电沟道应力与晶向的选择范围,给出的硅价带顶处重空穴带、轻空穴带能级间的分裂值和有效质量随应力的变化关系可为单轴〈111〉应力硅其他物理参数的计算提供参考.
关键词:
单轴应力硅
k·p法')" href="#">k·p法
价带结构 相似文献
995.
利用LEED图形拟合的方法对大量不同取向In/Si表面的稳定性和小面化进行了研究,新发现了In覆盖度在1/2单层原子以下的三个稳定表面:Si(214)-In,Si(317)-In和Si(436)-In,以及In覆盖度在1单层原子左右的两个稳定表面Si(101)-In和Si(313)-In.此外还确定了In覆盖度在1单层原子左右的6个稳定In/Si表面的家族领地以及In覆盖度在1/2单层原子以下的4个稳定In/Si表面的家族领地.特别值得注意的是 Si(103)-In的家族领地相当大,甚至比最稳定的Si(1
关键词:
硅表面
铟
稳定表面
家族领地 相似文献
996.
Silicon oxide (SiO2) and silicon oxynitride (SiOxNy) are two key dielectrics used in silicon devices. The excellent interface properties of these dielectrics with silicon have enabled the tremendous advancement of metal-oxide-semiconductor (MOS) technology. However, these dielectrics are still found to have pronounced amount of localized states which act as electron or hole traps and lead to the performance and reliability degradations of the MOS integrated circuits. A better understanding of the nature of these states will help to understand the constraints and lifetime performance of the MOS devices. Recently, due to the available of ab initio quantum-mechanical calculations and some synchrotron radiation experiments, substantial progress has been achieved in understanding the atomic and electronic nature of the defects in these dielectrics. In this review, the properties, formation and removal mechanisms of various defects in silicon oxide and silicon oxynitride films will be critically discussed. Some remarks on the thermal ionization energies in connection with the optical ionization energies of electron and hole traps, as well as some of the unsolved issues in these materials will be highlighted. 相似文献
997.
998.
A. N. Murashkevich A. S. Lavitskaya T. I. Barannikova I. M. Zharskii 《Journal of Applied Spectroscopy》2008,75(5):730-734
The composites xTiO2-(1−x)SiO2 (x = 0.1, 0.5, 0.9) were obtained by coprecipitation from solutions of alkoxides: tetraethoxysilane (TEOS) and titanium tetraisopropoxide
(TIPT). Intermolecular interaction of the components of the composite is apparent in the IR absorption spectra in the 928–952
cm−1 region, and is connected with bending vibrations of the Si-O-Ti bond.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 75, No. 5, pp. 724–728, September–October, 2008. 相似文献
999.
MA Li WANG Jian-Guang WANG Guang-Hou 《理论物理通讯》2005,44(10)
The adsorption of one monolayer S atoms on ideal Si(100) surface is studied by using the self-consistent tight binding linear muffin-tin orbital method. Energies of adsorption systems of S atoms on different sites are calculated.It is found that the adsorbed S atoms are more favorable on B1 site (bridge site) with a distance 0.131 nm above the Si surface. The S, Si mixed layer might exist at S/Si(100) interface. The layer projected density of states are calculated and compared with that of the clean surface. The charge transfers are also investigated. 相似文献
1000.
Open-circuit voltage analysis of p-i-n type amorphous silicon solar cells deposited at low temperature 下载免费PDF全文
This paper identifies the contributions of p-a-SiC:H layers and i-a-Si:H layers to the open circuit voltage of p-i-n type a-Si:H solar cells deposited at a low temperature of 125 C.We find that poor quality p-a-SiC:H films under regular conditions lead to a restriction of open circuit voltage although the band gap of the i-layer varies widely.A significant improvement in open circuit voltage has been obtained by using high quality p-a-SiC:H films optimized at the "low-power regime" under low silane flow rates and high hydrogen dilution conditions. 相似文献