次磷酸盐化学镀铜体系主组份变化研究进展

随着对环境保护的重视,以甲醛为还原剂的化学镀铜体系将被环境友好型的化学镀铜体系所取代。以次磷酸盐为还原剂的化学镀铜体系环保、工艺参数范围大、镀液寿命长,可能成为下一步的研究热点。对次磷酸盐化学镀铜体系中主要组份含量变化对沉积速率和镀层性能的影响进行了综述,对其发展方向进行了展望。     

PCB高稳定性中速化学镀铜工艺研究

主要研究微量添加剂对化学镀铜镀液沉积速率及镀液稳定性的影响,通过试验筛选合适的微量添加剂,在不改变化学镀铜镀液主反应物质含量的情况下实现镀速提高和镀液稳定性增加。开发出的高稳定性中速化学镀铜工艺,其性能满足PCB工业化生产。     

超声波在陶瓷基片化学镀铜中的作用研究

采用了将超声辅助化学镀铜工艺与传统化学镀铜工艺对比的方法，研究了超声波辅助处理在陶瓷基片化学镀铜（包括前处理）中的作用，结果表明：超声波辅助处理影响化学镀铜的全过程，具体体现为：超声波辅助除油及粗化处理有利于形成致密、表面平整度高的铜层、超声波辅助敏化和活化处理使铜层表面的平整度下降，超声波辅助处理对化学镀中铜的均匀沉积不利。同时分析了超声波辅助处理对沉积速率及铜层显微硬度的影响。     

次亚磷酸钠作还原剂化学镀铜工艺研究

近年来,化学镀铜技术在PCB行业、机械工业、航空航天等各行业有着越来越广泛的应用,有关化学镀铜的机理研究和工艺路线改进等课题已成为当今材料表面处理研究领域的热点之一。然而,以甲醛为还原剂的传统化学镀铜工艺受绿色制造的要求,其使用将受到限制,开发非甲醛体系化学镀具有巨大市场潜力。本文采用RF-4环氧树脂为基材,研究了以次亚磷酸钠为还原剂的化学镀铜工艺的改进,并且讨论了添加剂的加入对镀铜层形貌和性能的影响。     

员工培训实用基础教程（三）

在多层印制板制造过程中，传统孔金属化工艺使用很长时间，大致分成三大步：第一步基体镀前处理：为获得良好的化学镀铜层提供必备的基体表面。第二步活化处理：在清洁的基体表面上形成催化中心，在化学镀铜过程中起到“活化种”的作用，使不导电的基体表面能沉积上铜镀层。第三步就是化学镀铜。     

半导体硅上激光诱导选择性化学镀铜

利用YAG脉冲激光在n型硅基底上制备出了铜化学镀薄层,由激光剥离形成的微型图元通过化学镀铜工艺在硅基底上形成铜的微型结构。在化学镀工艺过程中为了使得化学镀铜沉积能够连续进行,要对基底表面先进行活化。实验表明,预处理及其后的清洗工艺对选择性镀膜质量影响很大;采用丙酮或硝酸水清洗,有助于获得清晰的微型图元结构。     

等离子体处理对ITO表面化学镀铜的影响

由于常规的化学镀铜层存在易剥落、不均匀、清洁度差等问题,所以提出在化学镀铜工艺之前增加等离子体处理工 序.通过改变等离子体功率、处理时间和处理距离等参数,使ITO表面获得较好的化学镀铜层.实验结果表明,处理距离越 短对减小水接触角、提高清洁度和附着力越有利;而等离子体功率和处理时间对基板表面状态的影响不是单调的.因此通...     

化学镀铜工艺中内层铜的可靠性

文章作者Crystal Li是罗门-哈斯电子材料亚洲有限公司（香港）电路板技术集团的研究技师。文章主要介绍化学镀铜过程中-目前做通孔或盲孔金属化最常用的制程,可能会影响PcB互联缺陷的一些因素。印制电路板的绝缘材料,其热膨胀系数高于铜材料。因此当焊接使温度升高时,介质的延展大大超过铜的延展。因此,导致增加的应力加到了内层互连的各个表面上。镀铜的通孔和内层铜之间必须要有非常强的结合力,才能使PCB成功地发挥其作用。如果化学镀铜和铜之间或内层化学镀铜和电解铜之间的结合力非常差,热应力就会导致互连缺陷（ICD）发生。     

用化学镀铜方法处理内层板

在多层印制板制造过程中,为了保证内层板与半固化片粘接可靠,内层板的铜箔表面都要经过氧化处理。然而,氧化处理后的铜箔表面经酸性溶液或加成法的化学镀铜溶液作用常常发生粉红圈现象。为了防止粉红圈的发生和提高粘接力,日立化成有限公司已开发出一种叫做K—6的化学镀铜溶液。 一、K—6化学镀铜溶液的组成成份和工作条件 K—6的组成成份与普通的加成法化学镀铜溶液的组成成份大致相同。K—6中含有一种特殊的添加剂—K—6添加剂,K—6添     

陶瓷电子元件局部化学镀铜电极的性能及结构

采用含钯的催化浆料活化法,实现了陶瓷表面的局部化学镀铜。扫描电子显微镜观察结果表明均匀分散的钯纳米颗粒起到了催化铜沉积的作用,镀铜层光滑平整、颗粒大小均匀。X-射线光电子能谱(XPS)和X-射线衍射(XRD)测试结果表明镀层是具有晶态结构的纯铜镀层。对化学镀铜后的陶瓷电子元件进行物理性能和电性能测试,其结果均满足工业要求。     

Characterization of sputtered tungsten nitride film and its application to Cu electroless plating

In this study, W and tungsten nitride films were fabricated by reactive sputtering in a N₂/Ar atmosphere, the native oxide growth on the surface of the tungsten nitride films was investigated by X-ray photoelectron spectroscopy (XPS). It was found that tungsten nitride films were the mixture of W and W₂N sputtered in atmospheres of 3 mTorr argon and at the N₂ partial pressure from 0.1 to 2.0 mTorr. The ratio of W and W₂N in films was changed with the nitrogen partial pressure in sputtered chamber. Surface oxidations of the W film and tungsten nitride films advanced with time. Electrochemical measurement shows that all reduction-oxidation (redox) potentials of tungsten and tungsten nitrides were lower than that of copper film in electroless copper solution. And so, electroless-plated copper could be deposited on the surface of tungsten nitride films when the substrates were immersed into electroless copper plating solution without any pretreatment. Tungsten nitride films are appropriate for ULSI Cu interconnections using electroless Cu deposition.     

在Ag导电胶上化学镀铜工艺

概述了由Ag导电胶形成的Ag导电膜上的化学镀铜工艺,其特征在于采用新的活化工艺取代传统的Pd催化剂,可以在Ag导电膜上形成均匀致密,无镀层扩展和优良附着性的化学镀铜层,特别适用于印制板的Ag导电胶上选择性化学镀铜。     

Electroless plating of copper on AZ31 magnesium alloy substrates

Chemical surface preparation for copper film on magnesium alloy by both electroless plating and organic coatings was studied. Organic coating was made by immersing the samples into an organosilicon heat-resisting varnish. A subsequent metallization process verified the applicability of this method. In this method, the organic coating acted as an interlayer between the substrate and copper film. When the reaction started, copper deposited directly onto the interlayer surface. X-ray diffraction and SEM analysis were used to understand the composition and morphology of the interlayer and copper film. The copper film has a rather perfect crystalline structure. And the result of the cross-cut test indicates the adhesion between the substrate is good enough. The potentiodynamic polarization curves for corrosion studies of coated magnesium alloys were performed in a corrosive environment of 3.5 wt% NaCl at neutral pH 7. The result reveals that compared with the substrate, the corrosion resistance of the coated AZ31 magnesium alloys increases distinctly. Moreover, the copper film has perfectly antibacterial and decorative properties. The method proposed in this work is environmentally friendly: non-toxic chemicals are used. In addition, this provides a new concept for plating the metals, which are considered difficult to plate due to high reactivity.     

电镀废液回收铜粉的化学镀银工艺及其电磁屏蔽性能

采用高频超声脉冲电解法从电镀铜废液中回收制备枝晶状的铜粉,并在铜粉表面进行化学镀银以制备电磁屏蔽用银包铜粉,采用SEM、EDS、XRD、TEM等对其进行形貌和组分分析,研究了银包铜粉复合涂层的导电性能和电磁屏蔽性能。结果表明,经过表面化学镀银可以有效地避免铜粉的氧化;涂层的电磁屏蔽性能与银包铜粉的添加量紧密相关,当涂层中银包铜粉质量分数为60%时,其电磁屏蔽效率高达52 dB。     

CoWBP capping barrier layer for sub 90 nm Cu interconnects

Electroless cobalt films have been obtained by deposition using a plating bath containing two reducing agents: dimethylamineborane (DMAB) and sodium hypophosphite. This formulation allows spontaneous activation on copper followed by auto catalytic electroless plating. CoWBP and CoBP films are proposed as diffusion barriers and encapsulation layers, for copper lines and via contacts for ULSI interconnect applications. The crystalline structure, chemical composition and oxidation states of the elements were studied, as well as the electrical resistivity, topography and morphology of the films. The film composition was characterized as a function of the solution composition; the barrier properties of the films were tested and an oxidation resistance study was conducted. The films were characterized and the results show that they can be applied as capping layers for ULSI copper metallization.     

Localized Ligand Induced Electroless Plating (LIEP) Process for the Fabrication of Copper Patterns Onto Flexible Polymer Substrates

The “ligand induced electroless plating (LIEP) process” is a simple process to obtain localized metal plating onto flexible polymers such as poly(ethylene terephtalate) and polyvinylidene fluoride sheets. This generic and cost‐effective process, efficient on any common polymer surface, is based on the covalent grafting by the GraftFast process of a thin chelating polymer film, such as poly(acrylic acid), which can complex copper ions. The entrapped copper ions are then chemically reduced in situ and the resulting Cu⁰ species act as a seed layer for the electroless copper growth which, thus, starts inside the host polymer. The present work focuses on the application of the LIEP process to the patterning of localized metallic tracks via two simple lithographic methods. The first is based on a standard photolithography process using a positive photoresist masking to prevent the covalent grafting of PAA in designated areas of the polymer substrate. In the second, the patterning is performed by direct printing of the mask with a commercial laser printer. In both cases, the mask was lifted off before the copper electroless plating step, which provides ecological benefits, since only the amount of copper necessary for the metallic patterning is used.     

Quality and reliability of high aspect-ratio blind microvias formed by laser-assisted seeding mechanism in PCB

The laser-assisted seeding (LAS) mechanism should be able to plate microvias with a high aspect ratio that may not be feasible by conventional electroless plating due to the small via geometry. In particular, the plating of microvias with a high aspect ratio close to one is difficult due to the limited accessibility of chemical solution to the via internal wall surface in conventional plating technology. LAS is a promising alternative. The objectives of this paper are to report the deposition mechanism of a thin copper film layer (laser-assisted seeding) on printed circuit board (PCB) microvias dielectric and to study the quality and reliability of the microvias produced by this mechanism. Results find that the microvias produced by LAS have acceptable quality and are as reliable as that formed by conventional electroless plating technology. The hole wall of the microvia was covered with deposited copper, and the thickness of which was found related to some LAS parameters. A set of experimental best LAS processing conditions is also given.     

次亚磷酸钠还原化学镀铜工艺研究及展望

化学镀铜是印制电路制作中重要工序,开发新的非甲醛体系化学镀铜工艺是当前化学镀铜领域中的热点。文章根据化学镀铜的基本原理,分析了以次亚磷酸钠为还原剂的化学镀铜工艺的特点、以及该技术的研究情况,并提出了该工艺未来的研究方向。