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71.
Etching characteristics of high-k dielectric materials (HfO2) and metal electrode materials (Pt, TaN) have been studied in high-density chlorine-containing plasmas at pressures around 10 mTorr. The etching of HfO2 was performed in BCl3 without rf biasing, giving an etch rate of about 5 nm/min with a high selectivity of >10 over Si and SiO2. The etching of Pt and TaN was performed in Ar/O2 with high rf biasing and in Ar/Cl2 with low rf biasing, respectively, giving a Pt etch rate of about several tens nm/min and a TaN etch rate of about 200 nm/min with a high selectivity of >8 over HfO2 and SiO2. The etched profiles were outwardly tapered for Pt, owing to the redeposition of etch or sputter products on feature sidewalls, while the TaN profiles were almost anisotropic, probably owing to the ion-enhanced etching that occurred. 相似文献
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阐述了方坯LF炉ET-DecNT全数字控制电极的结构及特点。该控制系统的使用,简化了操作程序,使设备加热曲线稳定,精炼炉的钢水喷溅量少,缩短了钢水的处理周期,实现了高效、低耗、优质和多品种的最佳化生产。 相似文献
76.
离子选择电极法测定氟化物过程中的质量控制 总被引:1,自引:0,他引:1
文章从氟离子选择电极的维护及其性能的判断、相应极限、空白电位值、参比电极的维护及其对电位值的影响、滤纸的使用以及溶液的pH值、温度、搅拌、电极浸入深度与位置、测定顺序等影响离子选择电极法测定氟化物的有关因素进行了研究和探讨,并提出对较复杂样品的测定易采用标准加入法以提高测定准确度和精密度。 相似文献
77.
SM-PDP中可以通过改变电极宽度,使放电空间的等位面沿电极增加的方向扩展,在等位面扩展的区域电场得到增强,从而改善SM-PDP的放电性能.但在性能改善的同时,相邻电极间的电感加大,输入功率增加,这对SM-PDP性能的提高是不利的.本文采用三维模拟方法,详细研究了在不同电极宽度情况下,SM-PDP放电单元的放电特性,为在设计SM-PDP时选择合适的电极宽度提供帮助. 相似文献
78.
Shengying Li Wu Yang Miao Chen Jinzhang Gao Jingwan Kang Youli Qi 《Materials Chemistry and Physics》2005,90(2-3):262-269
Nanosized lead oxide particles were prepared by thermal decomposition of lead hydroxycarbonate synthesized under microwave irradiation. Urea and lead nitrate were used as the starting materials. Microstructure and morphology of the products were investigated by means of XRD, AFM, TEM, and IR absorption spectra. The results indicated that well crystallized, finely dispersed and spherical -PbO nanoparticles with a size of ca. 30 nm were obtained. Meanwhile, an orthogonal phase β-PbO with a size of ca. 38 nm was also obtained when the calcinations temperature was up to 600 °C. In addition, a Pb(II)-selective electrode based on cellulose acetate was prepared using nanosized -PbO powders synthesized. The electrode exhibited a Nernstian slope of 29±1 mV per decade in a linear range of 2.5×10−5 mol L−1 to 1.0×10−1 mol L−1 for Pb2+ ion. The detection limit of this electrode is down to 8.0×10−6 mol L−1. This sensor has a short response time of about 10 s and could be used in a pH range of 2.0–8.0. High selectivity was obtained over a wide variety of metal ions. 相似文献
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A novel technique is introduced for planning experimental design employing fuzzy rule-based systems. The significant aspect of the proposed experimental design with fuzzy levels (EDFL) is assigning a membership function for each level of variable factors. Consequently, the design matrix and observed responses can be represented in a set of fuzzy rules. Several examples are presented to clarify the proposed idea and the results are compared with the conventional Taguchi methodology. We have specifically planned an L18 orthogonal array EDFL for the solder paste printing stage of surface mount printed circuit board assembly to provide a model for the process and to optimize the selection of variable factors. 相似文献