Ni电极X8R多层陶瓷电容器的制备及性能

采用具有抗还原性的X8R瓷粉、镍内电极浆料和柔性导电端头浆料为原料,制备了Ni电极X8R多层陶瓷电容器(MLCC),研究了烧结升温速率以及柔性导电端头浆料对所制MLCC性能的影响。结果表明:最佳烧结升温速率为2℃/min,制备的Ni电极X8R-MLCC在-55～+150℃范围内,容量变化率≤±15%,电性能优良,可靠性高,适用于汽车电子等高温应用领域。     

一种可代银的锌电极浆料

<正> 最近国外专利报导了一种锌导电浆料,特别适用于制作陶瓷电容器、可变电阻器以及其它电子元件的电极。 通常,陶瓷电容器和可变电阻器的电极浆料为银浆料,由银粉,玻璃粉和有机载体组成。但是,用贵金属银作电子元件电极,成本较高。     

层状钙钛矿型Bi_(3.15)Nd_(0.85)Ti_3O_(12)铁电薄膜在LaNiO_3/Si上取向生长的TEM研究

用溶胶-凝胶工艺在披覆了LaNiO3底电极的(100)Si衬底上制备了Bi3.15Nd0.85Ti3O12(BNdT)铁电薄膜.X射线衍射结果显示,LaNiO3层呈(110)择优取向,BNdT薄膜呈c轴和a/b轴混合择优取向.透射电镜观察表明,LaNiO3电极层和BNdT薄膜厚度分别约为180 nm和320 nm.BNdT薄膜分为上下两层,厚约100 nm的底层以薄片状c轴择优取向晶粒为主,在顶层许多柱状晶粒为a/b轴择优取向.讨论了BNdT薄膜在(110)LaNiO3电极上的择优取向生长机制.     

LaNiO3薄膜热稳定性的研究

LaNiO3导电金属氧化物薄膜在现代应用科学研究中作为电极和过渡阻挡层倍受青睐，它具有很好的导电特性和稳定性。该文采用射频溅射法制备了具有(100)择优取向的赝立方结构LaNiO3-x薄膜，并进行了原位热处理。实验结果表明，在265℃的处理条件下，LaNiO3薄膜表现出不稳定性，晶格中的氧在2h内失去了2.7％。氧的损失对品格结构没有明显影响，但薄膜的导电性能明显下降，折射率和消光系数也具有相同幅度的下降。对薄膜的应用具有一定的影响。该文从LaNiO3薄膜的导电机理方面对实验现象给出了分析和解释。     

无机添加剂对多层陶瓷电容器钯银内电极浆料的影响

为了满足多层陶瓷电容器陶瓷介质与钯银内电极浆料烧结一致性要求,研究了无机添加剂纳米BaTiO3和纳米ZrO2对钯银内电极浆料的烧结过程产生的影响。结果表明所用添加剂使MLCC烧结过程中钯银内电极浆料的收缩与陶瓷介质的收缩保持一致。     

多层陶瓷电容器用镍内电极浆料的现状与展望

多层陶瓷电容器(MLCC)是片式元器件中广泛使用的一类。集中介绍了MLCC用Ni内电极浆料的发展现状,对旨在针对其进行改良的大量研究进行了总结,重点介绍了Ni内电极浆料制备的关键技术,包括高分散性高纯镍粉的制备、有一定抗氧化能力的Ni浆及抗还原瓷料、镍内电极与介质层的烧成收缩控制及有机树脂体系的选配等,并对其进一步发展做出展望。     

基于PCB喷墨技术的纳米导电银浆的研制

喷墨技术应用到PCB将是一种趋势,而该技术的核心问题是导电浆料的制备。本文采用热溶剂化学还原法,还原AgNO3制得纳米银导电浆料,并通过XRD、TEM等手段表征了其结构及形貌。实验发现:在120℃下的纳米银为球、片混合状,粒径为40 nm左右,符合喷墨要求。最后经过导电浆料的制备及150℃下的烧结,测得其导电性良好,在环氧基材表面附着力强。     

碳膜电位器端头用铜银导电浆料的研究

碳膜电位器端头一般用银导电浆料,以微细片状银粉作导电相。本文的研究工作试图以铜代替部分银,并根据碳膜电位器端头导电性及表面光泽度的要求,适当调整铜扣银含量的比例,通过大量的实验,给出了最佳条件。     

空气中烧成镍电极浆料的研究

介绍了空气中烧成的Ni电极浆料的制备。讨论了浆料中玻璃粉、硼粉含量及烧渗工艺等对电极性能的影响。结果表明:浆料中Ni粉的纯度应为99.5%,粒度为500目;w(Ni)应不低于65%;玻璃粉的软化温度为450℃左右;粒度为300目,w(玻璃)为20%左右。加入硼粉系作为抗氧化剂。于810℃的大气中烧渗,保温5 min,此贱金属镍电极可牢固地附着在陶瓷基体上,并具有良好的欧姆接触性能。     

Mn2.1Ni0.9O4热敏陶瓷的制备与复阻抗分析

采用传统固相反应法制备了Mn2.1Ni0.9O4热敏陶瓷,运用X射线衍射仪、直流阻温测试仪、交流阻抗技术对其结构和电学性能进行了测试,并对Mn2.1Ni0.9O4热敏陶瓷的微观导电机理进行了分析。结果表明:Mn2.1Ni0.9O4热敏陶瓷由立方尖晶石相和岩盐相NiO组成。其电阻主要来源于晶粒和晶界的贡献,在293~363 K测试温区内,其晶粒电阻和晶界电阻都表现出明显的NTC特性,且两者导电机理均符合小极化子跳跃电导模型,晶界电阻受岩盐相NiO的影响大于晶粒电阻。     

Effects of silver oxalate additions on the physical characteristics of low-temperature-curing MOD silver paste for thick-film applications

In this paper, the effect of silver oxalate addition on physical characteristics of metallo-organic-decomposition (MOD) silver screen-printable paste for thick film technology was investigated. The addition of silver oxalate in the paste not only produces fresh fine silver particles after curing, but also reduces the decomposition temperature of the lubricant coated on the silver flakes. This is an effective route to provide fine silver particles to the paste without significantly changing the rheological behavior. At the curing temperature of 225 °C, the resistivity decreases from 180.1 to 31.9 μΩ-cm, as the silver oxalate content increases from 0 to 10 wt%. This is due to the fact that active silver catalysts produced increase the packing density of silver flakes, and also the removal of lubricant from the surface of silver flakes enhances the electrical conductivity, thereby decreasing the resistance of film.     

Electrical Conductivity of Thick Films Made from Silver Methylcarbamate Paste

We have explored the electrical conductivity of thick films made from silver methylcarbamate paste using metallic silver as the electrically conductive phase. The paste was composed of 30 wt.% to 90 wt.% organic vehicle and 10 wt.% to 70 wt.% functional phase precursor (silver methylcarbamate). After the paste was sintered, films with thickness of 4.50 μm to 12.70 μm were obtained, in which the elemental percentage of silver varied from about 5 wt.% to above 99 wt.%. Experiments showed that both the electrical conductivity and the elemental percentage were mainly affected by the initial silver content in the paste and the parameters of the sintering process. For given sintering conditions, higher initial silver content led to higher elemental percentage of silver, improving the electrical conductivity of the thick film. The conditions of the sintering process had a significant influence on the evaporation and decomposition rates of the paste components, the elemental percentage of silver, and the microstructure of the thick film. Higher temperatures, longer times, lower heating rates, and more oxygen-rich sintering atmospheres were found to accelerate the evaporation and decomposition and increase the elemental percentage of silver, both of which served to enhance the electrical conductivity. For initial silver contents less than about 10 wt.%, the lowest electrical resistivity of the thick film only reached the order of 10^?4 Ω cm, irrespective of the sintering conditions. For contents between 10 wt.% and 25 wt.%, it was possible to attain lowest resistivity values on the order of 10^?5 Ω cm. Above 25 wt.%, the lowest resistivity could reach 10^?6 Ω cm, comparable to that of bulk silver.     

立方晶银颗粒混入片状纳米银浆后导电效果的研究

纳米银有多种形态,高导电率的纳米银应具有片状结构,同时复合有部分小颗粒的球形纳米银。本文利用AgNO3和H2C2O4溶液反应使Ag2C2O4沉淀,分析草酸银的热分解行为,研究了分散性较好的球形纳米银晶状体颗粒的制备方法。实验表明:在配位剂三乙醇胺、DMF和分散剂PVP的存在下,利用AgC2O4的自身氧化还原性,在85℃左右加热4 min可得到球形纳米银晶粒,将其分散在乙醇中并混入之前制备好的片状纳米导电银浆中进行烧结,其导电效果好于结构单一的纳米银浆。     

多层陶瓷电容器端电极银浆料匹配问题的研究

针对多层陶瓷电容器一种自主研发的瓷料的银电极匹配问题,运用扫描电子显微镜分析了端电极烧结后的微观结构,并用能谱仪对其进行成分分析,结合实际的生产实践,找出与该瓷料匹配的银浆料。端电极用银浆由有机载体、玻璃料和银粉等组成。经封端、烘干和烧端形成ML-CC的端电极。实验结果表明:用2#银浆作端电极的MLCC具有附着力高、损耗低等特点,完全能满足该系列MLCC生产线的使用要求。     

低温共烧陶瓷内电极用导电银浆烧结匹配性能

采用优化后的玻璃粉配制成导电银浆,与MgSiO3-CaSiO3生瓷片共烧后形成导电厚膜,探讨了不同玻璃粉配方对所制厚膜的微观结构、热学性能、附着力、线膨胀系数和导电性能的影响,研究了导电银浆与基片低温共烧的匹配性能。结果表明,SiO2-Al2O3-B2O3-CaO-Li2O系玻璃粉配制的导电银浆低温共烧后获得的导电厚膜平滑、均匀、致密;随着该系玻璃粉中Li2O含量的增加,导电银浆的线胀系数逐渐降低;Li2O的质量分数为6%时,该浆料线胀系数最低,为18.482×10–6℃–1;Li2O的质量分数为2%时,导电厚膜与基片的线膨胀匹配性良好,导电性能最好,方阻为3.02 m?/□。     

Silver Surface Iodination for Enhancing the Conductivity of Conductive Composites

The electrical conductivity of a silver microflake‐filled conductive composites is dramatically improved after a filler surface treatment. By a simple iodine solution treatment, nonstoichiometric silver/silver iodide nanoislands form on the silver filler surface. Evidence of the decrease of surface silver oxide species is provided by TOF‐SIMS and the redox property of the nanoclusters is studied using cyclic voltammetry and TOF‐SIMS depth profile analyses. The redox property of the nanoclusters on silver flakes helps enhance the electrical conductivity of the conductive composites. The electrical resistivity of the improved conductive composites is measured by four‐point probe method; the reliability of the printed thin film resistors is evaluated by both the 85 °C/85% relative humidity moisture exposure and the −40 ∼ 125 °C thermal cycling exposure. The conductive composite printed radio frequency identification (RFID) antennas with 27.5 wt% of the modified silver flake content show comparable performance in the RFID tag read range versus copper foil antennas, and better than those commercial conductive adhesives that require much higher silver content (i.e., 80 wt%). This work suggests that a surface chemistry method can significantly reduce the percolation threshold of the loading level of the silver flakes and improve the electrical conductivity of an important printed electronic passive component.     

用于新型荧光字符平板显示器的银浆料

针对新型荧光字符平板显示器件的工艺特点，研制出了能满足其工艺要求的电极银浆料。该浆料的最佳峰值烧成温度为５５０～５８０℃，玻璃相含量５．５％～６．５％（质量分数）。用它制作的电极具有阻值低、附着力强、分辨率高等优点，可替代进口的同类浆料。     

叠层片式铁氧体电感器银端电极匹配研究

通过对比实验,运用扫描电子显微镜分析了银端电极烧银后的显微结构,并用能谱分析仪对三种烧银后的银端电极进行成分分析,找出与自主研发的叠层片式铁氧体电感器用软磁铁氧体粉料相匹配的银端浆.实验结果和工艺验证表明:Ⅲ号ML78银端浆具有直流电阻低(≤0.61Ω)、温升低(≤16.2℃)等特点,完全满足MLCI批量化生产的要求.     

一种用于太阳能电池背电极的超细球形铝粉浆料

采用具有不同粒径级配的球形铝粉制备了能够与硅片形成性能良好太阳能电池背电极的铝浆,并在硅片上制备了铝电极膜。研究了铝粉粒径级配对铝电极膜性能的影响。结果表明:随着超细球形铝粉(0.5~2.0μm)含量的增多,铝电极膜层的填充性、致密性得到了增强,太阳能电池的光电转换效率η得到了提高;与不含超细球形铝粉的样品相比,w(超细球形铝粉)为8%时的太阳能电池的η提高了约4%。超细球形铝粉含量过多(如15%)时,铝电极膜表面容易析出铝珠,电极膜机械强度降低甚至出现灰化脱落。     

用于氮化铝陶瓷基片的电子浆料

研制了用于ＡｌＮ陶瓷基片的导体银浆和电阻浆料。采用低ＰｂＯ含量晶化玻璃料配制银导体浆料，玻璃软化点４３０～４５０℃。电阻浆料采用ＰｂＯ（质量分数小于６％）的晶化玻璃料Ｂ、Ｃ、Ｄ三种，软化点分别为５２０℃、６９０℃、６１０℃。改变ＲｕＯ２与玻璃相的质量比，能控制电阻浆料的方阻值。质量比在５０比５０至１５比８５之间。加入添加剂ＭｎＯ２可改善电阻浆料的ＴＣＲ，阻值在２０Ω／□～１ＭΩ／□范围内，ＴＣＲ绝对值小于２００×１０－６／℃。