陈旧氰化镀银槽光亮镀银工艺探讨

光亮镀银比普通镀银有更多优越的性能，除了镀层美观外，在耐变色性、镀层细致性方面也都有明显的优势，此外还具有工艺操作简便、镀层结合力强、沉积速度快、成本低等优点。当前，各种功能镀银包括光亮镀银主要在氰化物镀银体系中得到，而且氰化镀银的光亮剂品种很多。本文对几种氰化光亮镀银工艺进行了比较，着重论述了用ＦＢ光亮剂作为陈旧氰化镀银添加剂的光亮镀银工艺及实践情况。实践证明，ＦＢ光亮剂不仅适用于新配制的氰化镀     

镀银含氰废水简便处理方法

氰化物镀银具有分散能力好、工艺简单、维护方便、镀液稳定等优点,而目前国内所试验的无氰镀银,例如硫代硫酸盐镀银、NS 镀银、磺基水杨酸镀银、烟酸镀银等,不是工艺上有一些问题,就是镀液稳定性不够,因此,没有被广泛用于生产。当前国内多数无线电厂还是采用氰化镀银。这样镀银含氰废水处理就显得相当重要了。我们对国内现有含氰废水处理方法进行分析、比较,提出适合我所情况的镀银含氰废水简便处理方法。首先介绍一下目前国内含氰废水简便处理方法、原理、工艺流程以及特点。     

菸酸镀银的应力及其控制

菸酸镀银属于无氰镀银工艺。许多文献报道了这种工艺具有镀液稳定,镀层细致,光亮等优点。有的文献还强调了这种工艺所制得银层具有良好的韧性。但是,本文作者在用菸酸镀银液制备镀银铜线时,发现在一定条件下,镀层会出现“脆性”。经过分析试验。证实这种脆性,是由于镀层内应力所引起的,它受电流密度,溶液组份,PH值等因素影响。同时,也可用镀后退火、时效等工艺来减小镀层内应力。文中结合试验情况,粗浅地讨论了应力产生原因。认为菸酸镀银的应力是由于镀银层在电沉积过程中银的点阵扭曲所造成的。     

印制板化学镀银涂覆处理工艺研究及质量控制探讨

本文在对一种印制板表面涂覆用无氰化学镀银工艺流程进行简单介绍的基础上，对所采用的无氰化学镀银工艺及质量控制技术进行了较为详细的论述：     

镀银三防处理及其防银变色工艺研究

本文分析了镀银层易变色及其在恶劣环境条件下耐蚀性差的原因；探讨了防银变色的机理；按国军标、国标和通用方法对采用不同的工艺措施获得的镀银层的防银变色性能、三防性能、接触电阻、焊接性能进行试验、评定及对比；找到了一种可以进一步提高镀银层三防性能及其防银变色性能的工艺措施。     

化学法镀银光纤的制造工艺研究

本文介绍了一种用化学法在光纤表面镀银的工艺及其设备。这种工艺的主要特点是不纤在拉丝过程中同时涂敷金属银，可得到有良好导电性的、连续的镀银光纤。     

印制电路铜面化学镀银及其高频信号传输损耗研究

传统还原型化学镀银溶液采用单一络合剂体系,存在镀液稳定性差、且由其产出的产品镀层均匀性差的问题,影响了产品的导电效果以及粗糙程度,不能满足高频信号传输对印制电路板的制作要求。在传统单一络合剂还原型化学镀银的工艺基础上,通过优化实验设计、实验室测试、粗糙度测试以及SEM测试,对化学镀银配方进行了研究与优化设计,得出了最佳的化学镀银工艺条件与双络合剂体系配方：银离子15 g/L,氨水50 ml/L,乙二胺20 ml/L,甲醛25 ml/L,乙醇25 ml/L,温度45℃,操作时间5 min,得到的化学银镀层光亮均匀、无发黄发灰现象,通过测试发现该化学镀银溶液稳定性提升,降低了工业成本,改善了粗糙程度,能够满足高频信号传输对印制电路板的制作要求,更好地应用于高频信号传输领域中。     

复杂铝合金零件镀银工艺改进

介绍了复杂铝合金零件镀银工艺,分析了影响铝合金电镀层质量的因素,通过试验改进了铝合金电镀工艺,在常规二次浸锌工艺中增加了电镀锌,采用浸锌电镀锌联合处理法提高了复杂铝合金零件镀银的结合力。给出了工艺流程及各工序溶液配方和相关参数,并提出了相应的操作要点。介绍了生产过程中易出现的问题及解决办法。利用划格法和热震法检验了镀层的结合强度。测试结果表明:采用新工艺加工的零件达到了结合力的要求。     

半导体器件制造中的镀银

半导体上导电和导热层的制备是现代电子器件制造工艺的一个基本的组成部分。本文讨论了:(1)欲具有优良性能的要求;(2)进而实现高效率生产的要求;(3)对可靠性可能产生的某些影响。为了弄清各种参数对工艺选择的影响,对选定的各种镀银工艺过程进行了比较。运用这样的经验标准,选择了一种目前能获得满意效果的专用槽液。     

资格认证专用教材《电子网版印刷技术》选编（连载二）：印制线路板的网版印刷

2．2 丝网印刷操作工艺过程 丝网印刷通常有机械自动印刷（见图4）和手工印刷两种。现侧重操作工艺过程及应注意的一些事项,以确保印刷质量。     

pH值及NaOH对化学镀银包铜粉镀覆过程的影响

采用化学镀法制备了不同加载量的树枝状银包铜粉,研究了镀液的pH值及NaOH的添加方式和添加量对镀覆过程的影响,并采用SEM、EDS、化学分析和氧化增重法对粉体性能进行了分析。结果表明:镀液pH值的最佳范围为11.0～11.5,NaOH的最佳质量浓度为10 g/L,直接加入主盐络合;在最佳工艺下,测得银包铜粉银的平均质量分数为23.06%±0.54%,银的平均转化率为98.0%±0.5%,微区表面银含量为质量分数39.17%～90.31%;所得银包铜粉包覆完全,抗氧化性良好。     

New plating bath for electroless copper deposition on sputtered barrier layers

A new copper plating bath for electroless deposition directly on conductive copper-diffusion barrier layers has been developed. This plating bath can be operated at temperatures between 20 and 50°C and has good stability. High temperature processing allows for increased deposition rates and decreased specific resistivity values for the deposited copper films. Electroless Cu films deposited from this bath showed a conformal step coverage in high aspect ratio trenches and, therefore, are promising as seed layers for copper electroplating. The effect of the bath composition, activation procedure and processing temperature on the plating rate and morphology of the deposited copper has been studied and is presented here.     

The effects of bath composition on the morphologies of electroless nickel under-bump metallurgy on Al input/output pad

The electroless nickel plating on an aluminum input/output (I/O) pad was investigated. The aluminum pad was pretreated in a zincate solution prior to electroless nickel plating. Zinc particles on the aluminum pad gave a good adherent nickel layer. The adhesion and uniformity of zinc on the aluminum is the key factor in under-bump metallurgy (UBM). The electrode potential changes with and without zinc ions in the bath were measured to analyze the sequence of two competing reactions: zinc deposit and hydrogen evolution. The relationship between aluminum dissolution and the ratio of zinc and NaOH was investigated. The electroless nickel deposition rate was dependent on bath composition. The effects of complexing ligand and additive on the nickel deposit were analyzed. Electrode potential changes were measured with time to confirm nucleation and grain growth. Adhesion of the UBM was related to zinc-particle dissolution and nickel nucleation. The uniform nickel UBM was fabricated on a real Al I/O pad.     

以酒石酸钠钾为络合剂的常温化学镀铜液研制

常温化学镀铜溶液具有反应温度低、甲醛自我分解少、维护费用低等优点。为了寻找合适添加剂并确定各组份最佳含量,获得一种反应活性好,维护简单的沉铜液,文中通过设计七因素三水平正交实验的方法,综合研究了沉铜液中各组份对沉积速率、溶液稳定性、镀层外观的影响,确定了一种以酒石酸钠钾为络合剂,甲醛为还原剂,稳定性较好、沉积速率较高、镀层外观较好的常温化学镀铜配方。     

Residual stress and interfacial reaction of the electroplated Ni-Cu alloy under bump metallurgy in the flip-chip solder joint

Pure Ni, the Ni-Cu alloy, and pure Cu layers as the under bump metallurgy (UBM) for a flip-chip solder joint were deposited by electrolytic plating. For the pure Ni layer, residual stress can be controlled by adding a wetting agent and decreasing current density, and it is always under tensile stress. The Ni-Cu alloys of different Cu compositions from ∼20wt.%Cu to 100wt.%Cu were deposited with varying current density in a single bath. The residual stress was a strong function of current density and Cu composition. Decreasing current density and increasing Cu content simultaneously causes the residual stress of the metal layers to sharply decrease. For the pure Cu layer, the stress is compressive. The Cu layer acts as a cushion layer for the UBM. The residual stress of the UBM strongly depends on the fraction of the Cu cushion layer. Interfacial reaction of the UBM with Sn-3.5 wt.% Ag was studied. As the Cu contents of Ni-Cu alloys increased, the dissolution rate increased. Several different intermetallic compounds (IMCs) were found. The lattice constants of alloys and the IMC increase with increasing Cu contents because the larger Cu atoms substitute for the smaller Ni atoms in the crystallites. The Cu content of the IMC are strongly dependent on the composition of the alloys. Ball shear tests were done with different metal-layer schemes. The failure occurs through the IMC and solder.     

New copper seed-layer enhancement process metrology for advanced dual-damascene interconnects

The extendibility of the physical vapor deposition (PVD), seed-layer deposition process for future devices needs to be enhanced with electrochemical techniques. Developing analytical techniques for the plating bath is a particular challenge because bath ingredients are often proprietary and difficult to ascertain. The feasibility of using an ion chromatography for an electrochemical copper, seed-layer enhancement (SLE) process metrology is studied. It is shown that the ion-chromatography method can be used to precisely determine the composition dynamics in a copper SLE plating bath. The bath concentration dynamics are found to be significant in influencing the electroplated Cu film properties, i.e., the resistivity and surface roughness. An excellent correlation exists between the ion chromatograms and the electroplated Cu film properties, suggesting that the ion-chromatography method is a powerful method.     

不锈钢化学镀Ni-P合金镀层的性能研究

讨论了不锈钢上化学镀Ni-P合金镀层的工艺,重点是不锈钢基体的前处理工艺、镀液温度和PH值.对镀层成分和结构的分析、结合力测试表明,用文中提出的前处理工艺对不锈钢基体处理后,再进行化学镀能获得性能可靠的Ni-P合金镀层.     

氧化铝陶瓷基板化学镀铜金属化及镀层结构

通过化学镀铜在氧化铝陶瓷基板表面实现了金属化,采用SEM研究了镀铜层表面微观形貌以及热处理的影响,检测分析了金属化镀层附着力。结果表明:通过控制镀液中铜离子浓度以及铜沉积速率,在基板表面可形成均匀致密的铜金属化层;热处理后进一步提高镀层致密化和导电性,其方阻由3.6 mΩ/□降为2.3 mΩ/□。划痕法测试表明镀铜层与氧化铝陶瓷基板结合紧密无起翘,可以满足敷铜基板的要求。     

Eutectic Sn-Ag solder bump process for ULSI flip chip technology

A novel eutectic Pb-free solder bump process, which provides several advantages over conventional solder bump process schemes, has been developed. A thick plating mask can be fabricated for steep wall bumps using a nega-type resist with a thickness of more than 50 μm by single-step spin coating. This improves productivity for mass production. The two-step electroplating is performed using two separate plating reactors for Ag and Sn. The Sn layer is electroplated on the Ag layer. Eutectic Sn-Ag alloy bumps can be easily obtained by annealing the Ag/Sn metal stack. This electroplating process does not need strict control of the Ag to Sn content ratio in alloy plating solutions. The uniformity of the reflowed bump height within a 6-in wafer was less than 10%. The Ag composition range within a 6-in wafer was less than ±0.3 wt.% Ag at the eutectic Sn-Ag alloy, analyzed by ICP spectrometry. SEM observations of the Cu/barrier layer/Sn-Ag solder interface and shear strength measurements of the solder bumps were performed after 5 times reflow at 260°C in N₂ ambient. For the Ti(100 nm)/Ni(300 nm)/Pd(50 nm) barrier layer, the shear strength decreased to 70% due to the formation of Sn-Cu intermetallic compounds. Thicker Ti in the barrier metal stack improved the shear strength. The thermal stability of the Cu/barrier layer/Sn-Ag solder metal stack was examined using Auger electron spectrometry analysis. After annealing at 150°C for 1000 h in N₂ ambient, Sn did not diffuse into the Cu layer for Ti(500 nm)/Ni(300 nm)/Pd(50 nm) and Nb(360 nm)/Ti(100 nm)/Ni(300 nm)/Pd(50 nm) barrier metal stacks. These results suggest that the Ti/Ni/Pd barrier metal stack available to Sn-Pb solder bumps and Au bumps on Al pads is viable for Sn-Ag solder bumps on Cu pads in upcoming ULSIs     

Degradation mechanism of ag-epoxy conductive adhesive/Sn-Pb plating interface by heat exposure

The compatibility between Ag fillers and Sn-Pb plating at elevated temperature was examined by mechanical test, electrical test, and microstructure observation. The degradation at 150°C is caused by the preferential diffusion of Sn from the plating layer into Ag in the conductive adhesive. By this diffusion, Ag-Sn intermetallic compounds formed in the Ag fillers adjacent to the plating layer, and many large Kirkendall voids are formed in the Sn-Pb plating layer. Furthermore, an interfacial debonding occurred between the conductive adhesive, and the Sn-Pb plating layer is also observed near the free surface after heat exposure.