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91.
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93.
Woo-Seok Cheong 《Journal of Electronic Materials》2003,32(4):249-253
For the lowest resistance, it is required to have the epitaxial silicon contact between the silicon plug and the substrate
and good step coverage at the high aspect-ratio contact holes, simultaneously. In this work, a double polysilicon (DPS) deposition
technique was proposed for the requirements. The first, thin silicon layer is deposited in a single-wafer process chamber
with an in-situ H2-RTP (rapid thermal process) treatment for the epitaxial contact, and the second silicon layer is formed in a batch-type furnace
for good step coverage. From chain resistance, Kelvin Rc, and current-voltage (I–V) measurement, the DPS process meets both low resistance and good uniformity, so that it suggests
a breakthrough in the small-sized, semiconductor device application. 相似文献
94.
XU Ying LIAO Xianbo DIAO Hongwei Li Xudong ZENG Xiangbo LIU Xiaoping WANG Minhua WANG Wenjing 《稀有金属(英文版)》2006,25(Z1)
Hetero-junction solar cells with an mc-Si:H window layer were achieved. The open voltage is increased while short current is decreased with increasing the mc-Si:H layer's thickness of emitter layer. The highest of V oc of 597 mV has obtained. When fixed the thickness of 30 nm, changing the N type from amorphous silicon layer to micro-crystalline layer, the efficiency of the hetero-junction solar cells is increased. Although the hydrogen etching before deposition enables the c-Si substrates to become rough by AFM images, it enhances the formation of epitaxial-like micro-crystalline silicon and better parameters of solar cell can be obtained by implying this process. The best result of efficiency is 13.86% with the V oc of 549.8 mV, J sc of 32.19 mA·cm-2 and the cell's area of 1cm2. 相似文献
95.
Two kinds of SiC whiskers were annealed at temperatures similar to those for the processing of ceramic matrix composites. The morphology and structure of the as-received and postannealed whiskers were investigated by SEM, TEM, and XRD, and the influence of processing temperature on the mechanical properties of ceramic matrix composites was discussed. 相似文献
96.
Hot electrons emitted from thin oxide film-coated heavily doped silicon electrodes by cathodic pulse polarization can induce electrochemiluminescence from luminophores. The intensity of electrochemiluminescence produced at the electrode surface is dependent on the features of thin oxide films formed by thermal oxidation. As a preliminary study, we investigated the effect of thermal oxide growth conditions on the intensity of electrochemiluminescence produced at these electrodes, such as oxidation atmospheres, oxidation temperature, oxidation time and pre-treatment of wafers, using ruthenium(II) tris-(2,2′-bipyridine) chelate as a model luminophore. Optimal oxidation conditions of heavily doped silicon electrodes were obtained for the generation of intense electrochemiluminescence at this kind of silicon electrodes. 相似文献
97.
Amorphous SiNx:H films were prepared by the rf glow-discharge decomposition of ammonia/silane gas mixture with varying nitrogen content. The steady-state photoconductivity and its dependence on light intensity have been investigated in a-SiNx:H as a function of temperature between 100 and 420 K. The electron drift mobility of a set of SiNx:H samples has been determined from their steady-state photoconductivity and response time measurements. The results suggest that electron drift mobility of the samples was nearly unchanged for a low nitrogen content. Two samples containing lowest nitrogen showed higher photoconductivity than that of unalloyed sample within a temperature range including the room temperature. 相似文献
98.
钛硅分子筛催化环己酮氨肟化反应过程--本征动力学 总被引:2,自引:0,他引:2
对钛硅分子筛(HTS)催化环己酮氨肟化反应本征动力学进行了研究。利用经验方程拟合了试验数据,并采用Marquardt算法对经验方程的参数进行确定,获得了不同试验条件下的反应初速率,然后再用高斯-牛顿法对本征动力学模型进行了参数估计,得出了氨肟化反应以及该反应体系中H2O2分解的本征动力学。并对该模型进行了残差分析和F检验,对氨肟化反应和H2O2分解的动力学模型的计算值与试验值进行了比较,获得相对误差绝对值的平均值分别为5.21%和6.25%。表明该模型能真实反映HTS催化环己酮氨肟化的反应特性,是合理可靠的,能为进一步的过程开发与工程设计提供一些理论上的指导和设计上的依据;而H2O2分解副反应动力学模型仅适用于该反应体系。 相似文献
99.
简要介绍了硅粉的理化性能,分析了WG硅微粉的形成过程,并进行了用于塑料制品的使用性能的试验研究,为硅粉用于塑料制品工艺提供了有利的借鉴。 相似文献
100.