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61.
多层片式瓷介电容器贱金属电极的制造方法 总被引:8,自引:2,他引:6
为了满足多层片式瓷介电容器MLCC小型化、大容量和低成本方向发展的要求,基于国内外对多层片式瓷介电容器以贱金属取代钯银体系作为电极的研究及应用,研究了以Ni为内外电极的BME-MLCC 的制作工艺,对工艺中排胶、烧成、烧端等关键工艺作了机理性探讨。通过选取电极材料、气氛控制和温度控制等,对以Ni为内外电极的多层片式瓷介电容器的制作工艺已经成功在实验室得到验证。 相似文献
62.
多层陶瓷电容器研究现状和发展展望 总被引:7,自引:0,他引:7
片式多层陶瓷电容器是新型片式元器件门类的主要品种之一.介绍了多层陶瓷电容器国内外研究现状和发展状况,重点介绍了镍内电极多层陶瓷电容器、高容量多层陶瓷电容器和高压多层陶瓷电容器,同时指出我国多层陶瓷电容器行业存在的问题和发展方向. 相似文献
63.
贱金属内电极多层陶瓷电容器研发进展 总被引:3,自引:0,他引:3
经过30多年的发展,贱金属内电极多层陶瓷电容器(BME-MLCCs)已经成为多层陶瓷电容器的主流产品.简要论述国内外对贱金属内电极多层陶瓷电容器研发状况和研究方向,重点介绍镍内电极多层陶瓷电容器发展历程,并且指出我国BME-MLCCs行业存在的问题和发展方向. 相似文献
64.
65.
水性粘合剂在电子陶瓷流延成型中的应用 总被引:5,自引:2,他引:3
总结了水性粘合剂的种类,分散形态,及其物理化学性质,如黏度、分子量、玻化温度等对电子陶瓷流延成型的影响,阐明了水性粘合剂对陶瓷浆料的稳定机理。从环保和MLCC高性能化的角度出发,指出采用水基流延的必然趋势,其重要研究方向在于提高水基流延的膜片强度。 相似文献
66.
67.
68.
Electrical properties of acceptor (Mn, Mg or Mn+Mg)-doped BaTiO3 ceramic have been studied in terms of oxygen vacancy concentration, various doping levels and electrical degradation behaviors. The solubility limit of Mn on Ti sites was confirmed to be close to or less than 1.0 mol%. Oxygen vacancy concentration of Ba(Ti0.995 –xMg0.005Mnx)O2.995 –y (x = 0, 0.005, 0.01) was estimated to be 50 times greater than that of the un-doped BaTiO3. The leakage current of 0.5 mol% Mn-doped BaTiO3 was stable with time, which was much lower than that of the un-doped BaTiO3. The BaTiO3 specimen co-doped with 0.5 mol% Mg and 1.0 mol% Mn showed the lowest leakage current below 10– 10A. It was confirmed that leakage currents of Mg-doped and un-doped BaTiO3 under dc field are effectively suppressed by Mn co-doping as long as the Mn doping level is greater than Mg contents. 相似文献
69.
Chung-Eun Lee Sun-Ho Kang Dong-Sook Sinn Han-Ill Yoo 《Journal of Electroceramics》2004,13(1-3):785-791
BaTiO3-based multilayer-ceramic capacitors (MLCC) using base metal (Ni) electrodes normally contains Mn and Y each approximately on the order of 0.5 mol%. It is only empirically known that the co-doping of Y and Mn facilitates sintering with the base-metal electrodes as well as improves the device performance and life time. In order to understand the effect of the co-doping, we have measured the electrical conductivity and chemical diffusivity on polycrystalline BaTiO3 that is co-doped with Y and Mn each by 0.5 mol% against oxygen partial pressure at elevated temperatures. It is found that while the n-type conductivity in reducing atmospheres (e.g., Po2 < 10– 6 atm at 1000C) remains similar to that of undoped or acceptor-doped BaTiO3, its p-type conductivity in oxidizing atmospheres (e.g., Po2 > 10– 6at 1000C) is remarkably suppressed compared to the latter. The chemical diffusivity is also similar to that of the latter in magnitude (e.g., 10– 2–10– 5 cm2/s at 1000C), but its trend of variation with oxygen partial pressure is rather opposite. These variations of the conductivity and chemical diffusivity are mainly attributed to Mn ions changing their valence from +2 to +3 to +4 with increasing oxygen partial pressure. It is explained from a defect-chemical view why the codoping of fixed-valent donor (Y) and variable-valent acceptor (Mn) has been practiced in MLCC processing. 相似文献
70.
P-type partial conductivity has been determined on donor (La
Ba
)-doped BaTiO3 in full thermodynamic equilibrium state at a fixed temperature of 1200°C: For the nominal compositions of Ba0.99La0.01Ti0.9975O3, Ba0.99La0.01TiO3 and Ba0.985La0.01TiO3, the p-type conductivity is found to vary with oxygen activity as p = (m/2)(a
O
2/a
O
2*)+1/4 with m 0.01 S cm–1 and a
O
2* 32, 120, 310, respectively, in the a
O
2 region where conventionally the electronic conductivity varies as aO
2
–1/4 and hence, the doped donors are believed to be compensated by cation vacancies (say, [LaBa
] 4[VPrime;Ti]). This experimental fact supports that in the vicinity of the stoichiometric composition of the system which falls approximately at a
O
2 = a
O
2*, while cation vacancy concentration is fixed by the donor concentration, oxygen vacancy concentration in the minority is also essentially fixed, thus, keeping the activity of TiO2 (or BaO) fixed. It is consequently suggested that donor-doped BaTiO3 contains a second phase even in its stoichiometric regime. 相似文献