应用于MEMS的单晶硅上无电镀铜、镀镍工艺

开发了单晶硅上的选择性无电镀铜、镀镍工艺，形成了较为优化的施镀流程，实现了保形性、均镀性较好的铜、镍及其复合镀层．其中针对单晶硅表面的特点，采取了浓酸处理和氧等离子轰击两种表面预处理方法，优化了氯化钯对表面的激活时间，使得镀层质量得到提高．提出了以镍作为中间层以减小镀层应力的方法，施镀后获得的铜镀层的电阻率为2.1μΩ·cm，铜/镍复合镀层的方块电阻为0.19Ω/□．在单晶硅MEMS电感结构上实现了较好的无电镀铜，使得该元件的品质因数超过25．     

PCB技术的革新与进步

文章概述了近几年来在PCB工业中生产技术的革新与进步情况,特别是直流电镀(镀层均匀性、填孔镀等)、表面涂(镀)覆(化学镀镍/钯浸金和直接浸金等)技术的革新与进步,推动了PCB工艺技术的发展。     

浅谈金川高冰镍传统精炼工艺技术改方案和镍产品结构调整

论述了金川有色金属公司现行高冰镍精炼工艺技改的必要性。在综合国内外高冰镍精炼技术的基础上,结合金川有色金属公司的实际,重点阐述了高冰镍硫酸湿法精炼和氯化精炼工艺的优缺点。指出,现行高冰镍精炼工艺的改造应吸取氯化精炼和硫酸湿法精炼两种工艺的长处,稳妥地向高冰镍全湿法精炼过渡。文中还对该公司镍产品结构调整提出看法。     

氯化物体系中镍阴极还原电化学行为

通过极化测量,对氯化物体系中镍阴极还原电化学行为进行研究,系统探讨了溶液中总镍浓度、氧化铵含量、氯化钠含量、硼酸浓度、电解液ＰＨ值及等工艺条件对阴极还原的影响,分析了镍阴极还原电化学行为变化的原因。本研究对氯化物体系中电解沉积镍粉具有指导作用。     

Electrical properties of nickel in silicon

Electrical activity and energy levels as well as diffusion properties of nickel in silicon have not yet been reliably established. In this paper, we investigated the diffusion and the electrical properties of nickel in silicon to confirm that nickel is electrically active and introduces one acceptor and one donor level by combined measurements of Hall coefficient and DLTS, and measurements of the distribution of electrically active nickel in various silicon diodes by DLTS. The former experiments show that bothn- andp- type silicon are compensated by nickel and that nickel introduces an acceptor level ofE _c-0.47 ± 0.04 eV and a donor level ofE _v +0.18 ± 0.02 eV. The concentrations of these two levels are almost identical over the diffusion temperatures from about 800 to 1100° C, indicating that these donor and acceptor levels are due to different charge states of the same nickel center. In the distribution measurements of electrically active nickel in silicon diodes, we inspected how nickel can be observed by DLTS. It was found that the nickel diffusion intop- n junction is rather complicated, the distribution profiles of nickel in the vicinity of thep- n junction being markedly influenced by an additional heating at elevated temperatures after the nickel diffusion. This gives evidence that the difference in silicon devices used in various studies could give rise to different results.     

The structure of tartaric acid adsorbed over nickel catalyst observed by FT-IRAS

The structure of the L-tartaric acid adsorbed on the surface of a nickel metal catalyst with or without NaBr was studied by FT-IRAS. The carboxylic acid and carboxylate type adsorbed species were observed on nickel surface which was treated with only tartaric acid, while only one type of carboxylate ion was observed on the nickel surface which was treated with tartaric acid and NaBr.     

The effect of sulfur on the dissociative adsorption of methane on nickel

The dissociative adsorption of methane was carried out on a Ni(100) surface covered with various amounts of sulfur under the high incident flux conditions of 1 Torr methane. Auger electron spectroscopy was used to measure the rate of carbon buildup and thus to determine the initial methane decomposition rates on the surface. It was shown that the sulfur atoms poison this reaction by a simple site-blocking process. These results are consistent with the activated dissociative adsorption of methane on Ni(100) occurring via a direct adsorption process.     

The hydrogenation of toluene over nickel loaded Y zeolites

The catalytic activities of a range of hydrogen reduced nickel Y zeolites for the hydrogenation of toluene were measured and correlated with the following catalytic parameters: reaction temperature; reaction time; coke deposition. The role of the alkali metal co-cation (Li⁺, Na⁺, K⁺, Rb⁺ or Cs⁺) in influencing the overall hydrogenation activity of the supported nickel metal was probed. The effect of poisoning the surface Bronsted acidity by the adsorption of ammonia is discussed. For comparative purposes, data on the hydrogenation of benzene over the same catalysts are included.     

Controlled-Pore-Size Composite Nickel Oxide Structures for Carbonate Fuel Cell Cathodes

The performance of a molten carbonate fuel cell (MCFC) is significantly eroded when fuel and oxidant gases are allowed to combine chemically as occurs with a loss of gas impermeability by the cell's electrolyte structure. This performance decline is eradicated when the cell's electrodes possess pore size distributions small enough to absorb sufficient electrolyte to act as a secondary gas barrier. Described here is a process for preparing composite MCFC NiO cathodes where the median pore size of the gas barrier region is varied from 3.2 to 0.4 μm by adjusting the starting powder's Ni/NiO ratio. When filled with liquid Li₂CO₃-38 mol% K₂CO₃ at 923 K, these structures possess a gas pressure resistance of between 2.3 × 10⁵ and 13.6 × 10⁵ Pa, respectively. The incorporation of these composite cathodes in a MCFC can prevent the penetration of the oxidant gas into the fuel cell's interior.