化学沉积法制备功能性化学镀锡层的研究

在紫铜表面制备了功能性化学镀锡层。用扫描电镜观察了化学镀锡层的表面形貌,用X射线衍射仪分析了化学镀锡层的物相,并用电化学工作站对化学镀锡层的耐蚀性进行了测试。结果表明:化学镀锡层表面比较致密,呈不规则的柱状结构;化学镀锡层的XRD图谱中出现了六个明显的锡衍射峰;化学镀锡层能为紫铜提供有效的保护,提高紫铜在质量分数为3.5%的氯化钠溶液中的耐蚀性。     

铜基引线框架电镀铜、银的显微结构及可焊性

在自动电镀线上对铜基引线框架表面分别镀铜和镀银。通过扫描电镜(SEM)和能谱(EDS)分析及钎焊试验对比了Cu镀层和Ag镀层的微观形貌、元素分布和焊接性。结果表明，银在引线框架基岛表面具有更好的沉积效果，所得Ag镀层平整光滑，结构致密。焊点在Ag镀层表面覆盖直径大于Cu镀层，表现出更好的焊接性。     

超声波化学镀锡及其性能研究

将超声波与化学镀锡工艺相结合,研究了镀液温度对超声镀锡层微观形貌、表面成分和耐腐蚀性能的影响.结果表明:超声波化学镀锡的沉积速度较常规化学镀锡提高了近30％,获得的超声镀锡层表面比较平整致密,表现出良好的耐腐蚀性能.随着镀液温度升高,超声镀锡层的耐腐蚀性能先增强后减弱,与表面状况发生明显变化有关.超声镀锡层成分未随着镀...     

自动电镀线拉片速率对引线框架镀层微观结构和钎焊性的影响

在自动电镀线上对铜基引线框架表面电镀铜镀层,并以Sn–Pb合金进行钎焊试验.采用扫描电镜(SEM)和能谱仪(EDS)考察了镀层和焊接截面的显微结构及元素分布,研究了拉片速率对镀层微观形貌、Sn–Pb合金的润湿行为以及焊接截面元素分布的影响.结果表明,拉片速率越大,铜的沉积时间越短,电镀层的致密性越差,对Sn–Pb合金的钎焊性也越差.以8 m/min拉片速率形成的铜镀层表面平整、致密,钎焊后的Cu/Sn界面连接完整,具有较好的微观结构和焊料润湿效果.     

化学镀锡预镀工艺对镀层质量的影响

研究了化学镀锡预镀溶液的组成和工艺条件对镀层厚度和表面形貌的影响.结果表明:预镀溶液的主盐和配位剂以及预镀时间对化学镀锡层的厚度影响较大;而镀锡层的表面随着添加剂的质量浓度的增加变得平整、致密.选择适宜的预镀液的酸度也可以提高镀层质量.     

电沉积条件对甲基磺酸锡镀层织构的影响

为了在实际应用中控制甲基磺酸电镀锡镀层的织构以提高镀层性能,采用X-射线衍射分析方法研究了镀锡工艺中表面活性剂浓度、电流密度和镀层厚度对镀锡层织构的影响规律,XRD分析结果显示,表面活性剂聚乙二醇辛基苯基醚(OP)浓度高,镀层以(211)和(321)晶面择优;OP浓度低,镀层以(101)和(112)晶面择优低电流密度有利于镀层以(211)和(312)晶面择优,高电流密度则有利于(101)和(112)晶面择优;镀层较薄时没有明显的晶面择优,(211)晶面的衍射峰强度随着镀层厚度的增加而加大,当镀层厚度超过10μm镀层以(211)和(321)晶面的衍射峰为主,且基本不随镀层厚度的增加而变化.由于晶态基底会影响镀锡层的织构和形貌,本甲基磺酸镀锡工艺以多晶紫铜化学镀非晶态镍磷合金为阴极,对非晶态基底上得到的锡镀层进行研究。     

化学还原法制备镀锡铜粉

采用硼氢化钠还原氢氧化锡,在铜粉表面进行化学镀锡,得到镀锡铜粉。用两面粗糙度不同的铜箔替代铜粉进行模拟试验,以研究锡层在铜粉表面的包覆情况和微观结构以及高温处理和制备方法对镀锡层显微结构的影响。结果表明,铜粉表面完整地包覆了一层均匀致密的镀锡层;采用还原法制备的镀锡层比采用置换法制备的镀锡层更为均匀致密,高温处理可进一步提高镀锡层的均匀性和致密性。     

低温化学镀锡工艺条件对锡层厚度的影响

研究了在低温、短时间条件下,化学镀锡液中主盐、配位剂、还原剂、pH值、温度、时间等因素对镀锡层厚度及沉积速率的影响,给出了一个在低温、短时间情况下合理的配方,并研究了镀锡层表面形貌随时间和温度的变化情况.结果表明,随着时间延长,温度上升,镀锡层表面晶粒不断增大,粗糙程度也随之增加.     

铈对镀锡引线可焊性的影响

探讨了稀土元素铈对电子元器件引线镀锡层可焊性的影响。结果表明,在氟硼酸盐镀锡溶液中加入适量的铈能提高镀液的稳定性,镀层的抗氧化性和可焊性,并可获得更为光亮的镀层。     

铜粗化QFN引线框架的量产制备方法

介绍一种铜粗化QFN(方形扁平无引脚封装)引线框架(Lead Frame)的量产制备方法。由于越来越多的半导体集成电路(IC)芯片应用端客户要求集成电路芯片的可靠性达到MSL1(湿气敏感性等级一级)的要求,芯片封装厂对引线框架的要求也越来越高。为了满足集成电路芯片可靠性MSL1的要求,我司开发了一种新型QFN引线框架,通过在铜合金表面电镀一层粗化的铜层,达到引线框架表面粗化的效果,增强引线框架与封装环氧树脂(EMC)之间的结合力,从而提高集成电路芯片的可靠性,并实现量产化。     

Charge-discharge characteristics of a layered-structure electroplated Cu/Sn anode for Li-ion batteries

An electroplated copper/tin (Cu/Sn) anode with a layered structure is described that minimizes the high-voltage irreversible capacity observed in an electroplated Sn anode at a potential over 1 V. The high-voltage irreversible capacity is caused by the electrolyte decomposition at the catalytic site of the Sn anode. In the electroplated Cu/Sn anode, the upper Cu layer effectively suppresses the exposure of the newly formed Sn surfaces, resulting in the absence of the high-voltage irreversible capacity. Therefore, the electroplated Cu/Sn anode exhibits a higher cycle performance than the electroplated Sn anode.     

ABS塑料与电镀层结合力差的原因分析及其控制

分析了ABS塑料在电镀铜/镍/铬时镀层出现起泡及结合力测试时镀层脱落的主要原因,包括塑件基体状态不良,注塑成型参数欠佳,电镀前处理不当,相邻镀层表面活性差等.给出了提高ABS塑件镀层结合力的措施,如选择优质的电镀级ABS塑料,控制成型工艺参数,改善前处理粗化及电镀工序中的活化处理等.强调了采用正确的结合力测试方法的重要性.     

一次氯化钾滚镀锌故障处理

对一次氯化钾滚镀锌故障进行了分析,并提出了处理方法。在目前的滚镀生产线上,基本上是用稳流器将镀槽的施镀电流控制在某一固定值附近,通过调整滚桶装载量的方式进行生产。由于氯化钾镀锌液中含有较多吸附性较强的大分子有机物添加剂,在电镀过程中这些添加剂在镀件表面脱附较慢。当电流密度较大时,镀层中就容易夹杂较多的有机物。在滚镀比表面积较小的零部件时,如果采用与电镀比表面积较大的零部件同样的施镀电流,则会产生不良镀层。因此,在氯化钾滚镀锌的生产中,除了调整滚桶装载量外,还需根据镀件比表面积调整施镀电流。通过改进传统的操作方法,排除了这次氯化钾滚镀锌的故障。     

Electroplating of a Co–Cu alloy from a citrate bath containing boric acid

The effects of bath composition, current density and temperature on cathodic polarization, cathodic current efficiency of codeposition, composition and structure of Co–Cu alloys electroplated on a steel substrate from citrate baths have been studied. Addition of boric acid to citrate electrolyte increases the percentage of Co in the deposits and improves the quality of these deposits. The cathodic current efficiency of the baths is relatively high and increases with increases in the metal content in the bath and the current density but decreases with temperature. The composition of the deposit is controlled by the applied current density. At low current densities, Cu‐rich alloys were obtained. At higher current densities, the composition of the alloys was controlled by the limiting current density of Cu codeposition. The Co content of the deposits increases with increases in the metal content in the bath and the temperature. The structure of the deposited alloys was characterized by anodic stripping and X‐ray diffraction techniques. The deposited alloys consisted of a single solid solution phase with a face‐centred cubic structure. © 2000 Society of Chemical Industry     

"电位活化"现象与无氰直接镀铜

"电位活化"现象认为,当金属离子在阴极还原的初始电位负于金属基体表面的活化电位时,电沉积的初始过程将首先完成对金属基体的活化,随后镀层沉积在活化的基体表面,形成具有牢固结合强度的电镀层。简要阐述了电位活化的研究概况和基本观点。应用电位活化概念对工艺进行改进,以提高焦磷酸盐镀铜、HEDP镀铜、乙二胺镀铜等无氰镀铜层在钢铁基体上的结合强度。     

提高挂镀锡镀层的均匀度

通过改善阴极与阳极导电能力,镀液的主要成分在辅槽配制分多次少量添加,最好用自动添加装置加入添加剂,镀液温度要均匀,且搅拌均匀,使用屏蔽板等措施提高了集成电路引线框架镀锡层的均匀度。并使稳定过程能力指数值达到1.33以上。提出了提高IC引线框架挂镀锡的稳定过程能力指数值的措施。     

Effect of a polyethoxylate surfactant on the electrodeposition of tin

The electrodeposition of tin in the presence of polyethoxylated additive TX-102 has been investigated in acid medium. The additive causes a substantial increase in the overpotential for the discharge of Sn²⁺ ions. Below 0.12 g dm^–3 the additive has little effect on the quality of the tin deposits. Periodic oscillations in the voltage of the cell are observed, which are associated with the initial growth of whiskers. For higher concentrations of additive, the deposits are smooth and homogeneous, and no growth of whiskers and no voltage oscillations are observed. The effect of TX-102 for concentrations below the CMC has been interpreted in terms of blockage of high energy sites of preferential growth on the tin surface. For additive concentrations above the CMC, micelles are formed. These high molecular weight aggregates also block the surface, hindering the mass transport of Sn²⁺ through a membrane-like layer that forms on the tin.     

电气铝排无氰镀铜的性能研究

比较了电气用铝排(6101铝合金)无氰镀铜与氰化镀铜后的镀层外观、金相、孔隙率、接触电阻、可焊接性、极化曲线的差异,并在不同工艺及厚度的镀铜层上电镀5μm厚度的锡层,通过Tafel极化曲线、中性盐雾试验、高温高湿试验对其耐腐蚀性能进行评估.结果表明,无氰镀铜光泽度好,接触电阻低,但整平能力、深度能力、可焊接性和孔隙率不...     

电流密度对5,5-二甲基乙内酰脲体系电镀银的影响

采用5,5-二甲基乙内酰脲体系在黄铜及不锈钢基体上沉积厚度为6μm左右的银镀层,镀液组成和工艺条件为:硝酸银25 g/L,5,5-二甲基乙内酰脲80 g/L,烟酰胺60 g/L,碳酸钾40 g/L,复合光亮剂(包含2-巯基苯骈噻唑、1,4-丁炔二醇和十二烷基硫酸钠)2 mL/L,pH 10.5,温度60°C,电流密度0...     

Assessment of Adhesion of Electroplated Cu and Multilayered Cu Coatings by a Bidirectional Bend Test

Abstract

Multilayered Cu coatings were successfully obtained by introducing periodic ultrasonic agitation into an ordinary electroplating process. A so-called bidirectional bending test technique was proposed to assess the adhesive performance of electroplated Cu coatings to a substrate, in which the coated sample was bent in two directions, while the changes in the coating surface were observed. The critical cycle number for the sample, which corresponds to the start of detachment of the coating from the substrate, proved to be suitable for assessing the adhesion. A comparative study showed that the multilayered Cu coatings produced in this work, had much better adhesion than did ordinary Cu coatings.