光纤光栅金属化工艺及特性研究

以石英光纤光栅为基体材料,采用化学镀镍和电镀铜相结合的工艺制备金属化光纤光栅。采用胶体钯活化法进行光纤光栅的活化处理,通过研究预处理粗化时间、活化时间与活化温度关键参数等对镍磷合金镀层结合强度和连续性等性能的影响,确定了最佳工艺条件:室温下粗化时间2~10 min,活化温度30~40℃,活化时间20 min,在石英光纤表面得到了连续、致密、均匀、光亮和附着力强的镍镀底层。采用电镀法在镀镍光纤光栅上继续镀铜,得到了具有高附着力、低电阻和良好焊接性能的金属化光纤光栅。对镀铜光纤进行温度性能测试,发现镀铜处理后的光纤光栅温度灵敏系数是普通光纤光栅的1.7倍。     

陶瓷表面激光无钯活化及其化学镀镍

为了实现陶瓷基体表面无钯化学镀镍,以10g/L NiSO₄·6H₂O和45g/L NaH₂PO₂的混合溶液为活化液涂覆于基体表面,利用激光扫描后使基体活化,再进行化学镀镍。研究了激光功率、光斑直径以及扫描速率对镀层覆盖率的影响,通过扫描电镜观察了粗化、活化以及施镀后的微观形貌,并对活化及施镀后的基体表面进行了成分分析,对镀层结合性、导电性以及可焊性进行了检测。结果表明,当以激光功率为3W、光斑直径为2mm、扫描速率为5mm/s对基体进行扫描时,基体表面生成一层平均直径为0.1μm的Ni微粒;施镀后,镀层覆盖率为100%;镀层微观表面平滑、致密,晶胞直径均在10μm以上;镀层中P的质量分数为0.0771,为非晶态结构,具有良好的耐磨性和耐腐蚀性能;镀层具有较强的结合性和良好的可焊性,电阻率为7.67×10-5Ω·cm,为良导体。该工艺成本低、无污染,能实现陶瓷基体表面局部化学镀镍,通过对激光的运动控制,能够使基体表面沉积各种精细图形,具有一定的实用价值。     

基于有机基板的化学镍钯浸金工艺应用与测评

有机基板被广泛应用于电子封装领域,常见的表面处理工艺包括电镀镍金、化学镍金、浸锡、浸银等工艺。在众多表面处理工艺中,化学镍钯浸金工艺因其具有较好的综合性能展现出显著优势。化学镍钯浸金工艺是在化学镍金工艺的基础上增加化镀钯处理,采用该工艺先对基板表面进行化镀镍处理,再进行化镀钯处理,最后完成化学浸金处理。钯镀层可以防止金在沉积过程中腐蚀镍镀层以及阻挡镍向金属间化合物（IMC）层扩散。利用X-Ray、电子扫描显微镜（SEM）、聚焦离子束（FIB）等图像分析方法,对比了不同厂商的化学镍钯浸金镀层的厚度、微观形貌及质量,结果表明,平整且致密的钯镀层可以有效避免镍腐蚀现象。     

塑料表面激光选区活化及其电子线路成型

为了实现低成本的精细电子线路快速成型,以CuSO₄和NaH₂PO₂混合溶液为活化液,涂覆于基体表面形成活化层,采用450nm蓝光激光对基体表面活化层进行扫描,从而使基体活化,并结合化学镀铜,在激光扫描区域制备出了导电金属铜层。研究了CuSO₄和NaH₂PO₂的质量浓度、扫描速率和涂覆次数对镀层成型效果的影响,对活化后的基体进行了能谱分析,通过扫描电镜对各阶段镀层相貌进行了表征,并对镀层的结合性和导电性进行了检测。结果表明,当CuSO₄和NaH₂PO₂的质量浓度分别为10g/L和30g/L、扫描速率为320mm/s、涂覆次数为3次时,镀层覆盖率为100%;激光扫描后,活化层中的Cu2+被还原为Cu微粒;镀层线路微观结构均匀致密、轮廓清晰、边界整齐、结合性强,表面电阻趋近于0Ω,导电性良好。该工艺在一定程度上解决了激光诱导技术可操作性差以及贵金属涂布成本高的问题,具有较高的实用价值,在电子线路成型方面具有一定的应用前景。     

化学镀镍/化学镀钯/浸金表面涂覆层的再提出

文章概述了化学镀镍/化学镀钯/浸金表面涂(镀)覆层的特性.不仅它能够满足各种各样的类型元件和安装工艺的要求,而且也能满足高密度的IC基板封装的要求.因而,化学镀镍/化学镀钯/浸金表面镀层是一种"万能"的镀层,具有最广泛的应用前景.     

酸性光亮镀锡层的可焊性

由酸性光亮锡试验数据表明,镀层可焊性效果好坏与镀后老化程度有关而与镀液光亮剂浓度和镀层厚度无关。然而,即使镀层遭严重老化,浸盐酸溶液就会使锡层表面得到活化。     

ENEPIG控制以获得优良封装基板表面处理焊区

本文针对ENEPIG(化镍钯浸金)技术应用于封装基板表面处理,在化镍钯浸金工艺过程中,通过对镍层上化学镀钯控制、浸金控制,获得精确的沉积厚度和金层均匀性,达到良好的接触面。并就浸金过程中的渗金问题进行优化控制,达到焊区小间距的需求。通过对ENEPIG表面处理焊区和电镀镍金表面处理焊区的Wire Bonding(引线键合)能力、可焊性、抗老化能力进行试验比较,验证了本ENEPIG控制技术同时具有优于电镀镍金的引线键合可靠性和锡焊可靠性。本ENEPIG控制技术所获得优异可靠性的表面处理,并且满足无铅组装工艺所有需求,非常适用于封装基板的表面处理制造。     

AlN陶瓷表面化学镀镍工艺

采用化学镀镍的方法对AlN陶瓷进行金属化。研究了陶瓷表面粗化工艺、化学镀溶液成分等对镀层的影响,得到了最佳工艺：采用500 g.L-1的NaOH溶液对AlN陶瓷进行30 min腐蚀粗化,可得到理想的粗化表面;采用的十二烷基硫酸钠作为镀液表面活性剂,浓度为100 mg.L-1,可减少镀层中的氢含量,使得镀层更加致密。将金属化后的AlN陶瓷与SiCp/Al复合材料焊接,剪切强度可达到110 MPa。     

镀镍钴粒在压水堆服役的可行性研究

为初步研究钴粒电镀镍层在无中子辐照的压水堆稳态工作条件下服役的可行性及极端事故工况对电镀镍层的影响,先后将镀镍钴粒在2 MPa氦气环境下400℃、600℃热处理240h、0.5 h.用扫描电镜对电镀镍层的表面和断面形貌进行了表征,用能谱仪分析了镀层与基体的界面元素扩散情况.结果表明镍镀层在居里温度358℃附近的热膨胀系数突变以及钴基体在427℃附近的相变不会对镍镀层造成破坏性损伤,界面的元素互扩散使镀层与基体的结合更加紧密.     

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。     

Optimization of black oxide coating thickness as an adhesion promoter for copper substrate in plastic integrated-circuit packages

Copper-oxide coating applied onto the copper substrate has emerged as an alternative to metallic coatings to improve adhesion with polymeric adhesives and molding compounds. The interfacial-bond strengths between the black oxide-coated Cu substrate and epoxy-based, glob-top resin were measured in button-shear tests, and the failure mechanisms were identified from the fracture-surface examination. The emphasis was to establish the correlation between the coating thickness, the surface roughness, and the interfacial adhesion with respect to treatment time. It was found that at the initial stage of treatment a thin layer of flat, cuprous oxide developed, above which fibrillar-cupric oxide was formed with further treatment until saturation with densified fibrils at about 150 sec. The interfacial-bond strength between the oxide-coated copper substrate and glob-top resin increased gradually with increasing treatment time, until the bond strength reached a plateau constant after a treatment for about 150 sec. There was a functional similarity between the oxide thickness, the surface roughness, and the interface-bond strength with respect to treatment time. A treatment time of 150 sec is considered an optimal condition that can impart the highest interface adhesion.     

衍射光学元件制作中的基片涂胶方法

在基片上涂布一层厚度均匀的光刻胶层,是衍射光学元件制作中的一个重要步骤。介绍了目前用于衍射光学元件制作的两种主要涂胶方法———提拉法和旋转法,分析了这两种方法的特点和影响胶层厚度的主要因素,尤其是对其均匀性的影响,并提出了获得均匀胶厚的途径。对于提拉涂胶,选择粘度较高的光刻胶溶液与合适的提拉速度将有助于减小Marangoni流动和Van derWaals力对膜厚均匀性的影响;对于旋转涂胶,可以通过密封基片所在空间,或者通过气流控制器使基片上方空气流动处于层流状态来获得均匀一致的溶剂挥发速率,从而提高胶层的均匀性。     

激光熔覆Mn-Cu合金涂层电解腐蚀前后的微观结构研究

用激光熔覆的方法在中碳钢表面制备了不同成分的Mn-Cu合金涂层,并对其进行了快速激光熔凝处理.以优化工艺参数制备的合金涂层表面光洁、成形良好、稀释率低并与基体形成了冶金结合.对合金涂层进行了特定参数的电解腐蚀后,得到了纳米多孔结构的Cu涂层.研究表明化学成分对合金涂层以及由电解腐蚀得到的多孔涂层的微观结构具有显著的影响作用.     

Effects of dimple and metal coating on interfacial adhesion in plastic packages

This paper reports on the effects of dimple and metallic coating of the Cu-alloy lead frame on interfacial adhesion with an epoxy-molding compound. Round dimples of varying number are introduced on one side of the lead frame by chemical etching. The plating materials studied include bare-Cu alloy and microetched Cu, Ag, Ni, Pd/Ni, and Au/Ni coatings. The surface characteristics, such as wettability, surface roughness, and element compositions, were evaluated based on several characterization tools, which, in turn, are correlated with adhesion performance. The dimples enhanced the interfacial-bond strengths through improved mechanical interlocking of the molding compound, depending on the type of coating. The improvement was much more significant for the coatings with inherently weak interfacial adhesion (e.g., microetched Cu and Ni coating) than those with inherently strong adhesion characteristics (e.g., Au and Pd coatings). The wettability of the metal surface represented by the surface energy or interfacial energy played a dominant role in the resulting interfacial adhesion. Elemental analysis of the fracture surface indicates that the silicon content had roughly a linear relationship with the interfacial-bond strengths for different coatings. The surface roughness was insensitive to the interfacial-adhesion performance. The silicon content measured from the lead-frame fracture surface was shown to directly correlate to the interfacial-bond strength. Higher silicon content was a reflection of larger surface-area coverage by the molding compound associated with cohesive failure.     

激光烧蚀坑阵列微结构对7075-T6粘接强度的影响

为了研究脉冲能量和烧蚀坑重叠率对7075-T6铝基板粘接强度影响, 采用纳秒光纤脉冲激光在粘接区域加工烧蚀坑阵列微结构, 通过表面形貌、剪切强度和断裂模式等实验参量对粘接效果进行了分析。结果表明, 脉冲能量对表面形貌、剪切强度及断裂模式几乎无影响; 随着烧蚀坑重叠率的增加, 表面粗糙度先增加后减小, 表面面积增加比一直增加; 与原始材料相比, 激光处理后剪切强度至少提升150%;当烧蚀坑重叠率为30%时, 粘接区域发生内聚断裂的面积最大, 剪切强度提升最明显; 脉冲能量为880μJ、烧蚀坑重叠率为30%时, 剪切强度为27.76MPa, 提升最大。该研究对激光烧蚀提高7075-T6粘接强度是有帮助的。     

RF Shielding Effectiveness and Light Transmission of Copper or Silver Film Coating on Plastic Substrate

RF shielding effectiveness and light transmittance of acopper or silver film coating on a plastic substrate is investigated. The dependence of the RF shielding effectiveness upon the surface resistance or thickness of a copper or silver film coating on a plastic substrate is calculated numerically by means of multireflection transmission-line theory over the frequency range of 100 MHz to 30 GHz. The light transmansmittance is determined by using the optical properties of the copper or silver film and plastic substrate. An optimum condition between the RF shielding effectiveness and the light transmittance is established for the copper or silver film coating on a plastic substrate.     

纯铜表面脉冲激光熔覆Ni60涂层的结构与性能研究

为了克服纯铜表面激光熔覆时热量难以积聚的困难,得到冶金结合良好的Ni60熔覆层,采用预热辅助脉冲激光熔覆的方法,在纯铜表面进行了Ni60合金粉末的熔覆实验,并建立了纯铜表面预热辅助脉冲激光熔覆过程的3维瞬态热弹塑性模型,对温度场及残余应力进行了仿真。预热温度达到573K时,Ni60熔覆层中裂痕完全消除;预热温度为673K时,激光熔覆的加工效率提升了2.2倍;预热辅助脉冲激光熔覆得到的Ni60熔覆层平均硬度达到800HV_0.2;常温下,Ni60熔覆层与ASTM52100钢相对耐磨性为4.45,摩擦系数约是铜和ASTM 52100钢的57%。结果表明,随着预热温度的升高,Ni60熔覆层中裂纹减少,激光熔覆效率提高;Ni60熔覆层有效地提高了表面硬度,减小了摩擦系数。通过预热辅助脉冲激光熔覆技术,在纯铜表面制备得到无裂纹、无气孔的Ni60熔覆层,可有效地提高铜基材的硬度与耐磨性。     

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.     

激光熔凝NiAl/纳米Al2O3化学复合镀层抗高温氧化性能

采用大功率连续横流CO2激光对化学复合镀NiAl/纳米Al2O3复合镀层进行激光熔凝处理,并对熔凝层的抗高温氧化性能进行研究。采用X射线衍射仪(XRD)、扫描电镜(SEM)和能谱仪(EDS)等分别对高温氧化前后的表面形貌、物相组织和元素组成进行表征分析。与复合镀层和基体试样相比,激光熔凝后表面抗高温氧化性能明显提高,这一方面与激光熔凝镀层中的金属间化合物NiAl2O4、Ni0.77AlFe0.23在800℃时具有良好的抗高温氧化性有关,另一方面是由于激光熔凝后镀层表面形成了连续致密的氧化膜。     

宽带激光熔覆梯度稀土生物陶瓷涂层的生物活性

为了减少激光熔覆过程中基材与生物陶瓷涂层之间的热裂纹, 提高涂层与基材的结合强度, 设计了一种梯度稀土生物陶瓷涂层, 采用宽带激光熔覆技术,在TC4钛合金表面制备了含HA＋β－TCP活性相的稀土活性梯度生物陶瓷复合涂层。利用SEM 、XRD分析手段对涂层形貌、相组成进行了研究; 通过模拟体液(SBF)浸泡实验(浸泡7 、14 d)考察了生物陶瓷涂层的生物活性; 利用电化学分析仪测试了生物活性陶瓷涂层的耐腐蚀性。结果表明, 当稀土氧化物Nd2O3添加量为w(Nd2O3)＝0.6%时, 宽带激光熔覆过程中催化合成HA＋β－TCP活性相的数量最多, 具有优异的表面形貌; 当稀土氧化物Nd2O3添加量为w(Nd2O3)＝0.6%时, 梯度稀土生物陶瓷涂层在SBF中浸泡不同时间点后表面沉积的类骨磷灰石相数量均较未加入Nd2O3的梯度生物陶瓷涂层多, 具有最好的生物活性, 且耐腐蚀性最佳。