化学镀技术在超大规模集成电路互连线制造过程的应用

总结自大马士革铜工艺建立以来,电化学工作者利用化学镀技术围绕该工艺而开展的一系列相关研究,介绍了应用化学镀沉积镍三元合金防扩散层和化学镀铜种子层的研究以及离子束沉积法(Ion ized C lus-ter Beam,ICB)形成Pd催化层后的化学镀铜技术和超级化学镀铜方法.简要叙述化学镀铜技术在超大规模集成电路中的应用,总结化学镀铜技术的研究进展,并指出了今后的发展方向.     

超级化学镀铜填充微道沟的研究

超级化学铜填充技术不仅可以应用于半导体超大集成电路铜互连线, 而且可以应用于三维封装. 研究了不同浓
度、不同分子量的PEG 对以甲醛为还原剂的化学镀铜溶液中铜的沉积速率的影响. 随着添加剂PEG 浓度和分子量的
增大, 化学铜的沉积速率明显降低. 电化学研究结果表明PEG 通过抑制甲醛的氧化反应降低化学铜的沉积速率, PEG
分子量越大, 对化学铜的抑制作用越强. 利用PEG-6000 对化学铜的抑制作用和在溶液中低的扩散系数, 采用添加
PEG-6000 的化学镀铜溶液, 成功地实现了宽度在0.2 μm 以下微道沟的超级化学填充. 就PEG 的分子量、微道沟的深
径比等因素对超级化学铜填充的影响也做了研究.     

芯片制造中的化学镀技术研究进展

芯片制造中大量使用物理气相沉积、化学气相沉积、电镀、热压键合等技术来实现芯片导电互连. 与这些技术相比, 化学镀因具有均镀保形能力强、工艺条件温和、设备成本低、操作简单等优点, 被人们期望应用于芯片制造中, 从而在近年来得到大量的研究. 本综述首先简介了芯片制造中导电互连包括芯片内互连、芯片3D封装硅通孔(TSV)、重布线层、凸点、键合、封装载板孔金属化等制程中传统制造技术与化学镀技术的对比, 说明了化学镀用于芯片制造中的优势; 然后总结了芯片化学镀的原理与种类、接枝与活化前处理方法和关键材料; 并详细介绍了芯片内互连和TSV互连化学镀阻挡层、种子层、互连孔填充、化学镀凸点、再布线层、封装载板孔互连种子层以及凸点间键合的研究进展; 且讨论了化学镀液组成及作用, 超级化学镀填孔添加剂及机理等. 最后对化学镀技术未来应用于新一代芯片制造中进行了展望.     

铜互连电镀中有机添加剂的合成与分析（英文）

铜互连是保障电子设备的功能、性能、能效、可靠性以及制备良品率至关重要的一环。铜互连常通过在酸性镀铜液电镀铜实现,并广泛用于芯片、封装基材和印制电路板中。其中,有机添加剂在调控铜沉积完成沟槽填充、微孔填充以形成精密线路和实现层间互连方面起着决定性作用。添加剂主要由光亮剂、抑制剂和整平剂三组分组成,在恰当的浓度配比下,添加剂对于盲孔超级填充具有协同作用。目前,已报导的文献聚焦于代表性添加剂的超填充机理及其电化学行为,而对于添加剂的化学结构与制备方法鲜有深入研究。本文重点研究了各添加剂组分的制备工艺和快速电化学筛选方法,为电镀铜添加剂的未来发展提供理论指导。     

高密度互连印制电路板孔金属化研究和进展

孔金属化互连是印制电路板（PCB）高密度集成的核心制程之一,化学镀铜和电子电镀铜是实现孔金属化的关键技术。本文介绍HDI-PCB的概念和制作流程;综述化学镀铜和电子电镀铜孔金属化互连的研究和进展,包括溶液组成和操作条件的影响,添加剂及其相互作用机理,以及盲孔填充和通孔孔壁加厚机制;展望高密度互连印制电路板电子电镀基础研究及新技术发展方向。     

铜电化学沉积在微孔金属化中的应用

以分布有微孔的印刷线路板(PCB)作为模板,按照PCB孔金属化工艺路线,研究乙醛酸化学镀铜和柠檬酸盐体系铜电沉积工艺在PCB微孔金属化中的应用.结果表明,乙醛酸化学镀铜和柠檬酸盐体系电沉积铜可以成功地应用于PCB微孔金属化加工工艺中.微孔化学镀铜金属化导电处理后,铜附着于微孔内壁,颗粒细小,但排列疏松且局部区域发生漏镀现象.微孔一经电镀铜加厚,镀层电阻显著下降;孔壁内外的铜沉积速率达到0.8:1.0;铜颗粒具有一定的侧向生长能力,能够完全覆盖化学镀铜时产生的微小漏镀区域;微孔内壁铜镀层连续、结构致密并紧密附着于内壁,大大增强了PCB上下层互连的导电性能.     

化学镀钴基合金镀液中钴的快速测定

研究了采用显色剂 苦胺酸偶氮变色酸对化学镀钴基合金镀液中钴含量进行测定的试验条件,在pH11的氨 氯化铵缓冲溶液中,钴与显色剂配合物的最大吸收峰在650nm波长处,钴(Ⅱ)在0～60μg/25ml范围内服从比耳定律,表观摩尔吸光系数为3.1×104L·mol-1·cm-1。该法测定钴的选择性好,在大量镍存在下,也能准确测定,对镀液样品进行了测定,相对标准偏差小于1%,结果满意。     

聚合物材料表面化学镀铜的前处理研究进展

聚合物材料表面金属化在通讯、电子、航空航天领域具有重要应用. 化学镀铜是聚合物材料表面金属化的主要技术之一. 聚合物材料表面的前处理直接影响化学镀铜层的结合力及镀层平整度. 本综述详细介绍非导电聚合物材料的种类、组成以及性能, 并概述其表面化学镀铜前处理的研究进展.     

不同化学镀液中p－Si上激光诱导局部沉积铜

在化学镀铜浴液中,p-Si片在彼长为514.5nm的激光束的照射下,得到了选择性的铜镀层。采用AEs、SEM、RBS和电学技术对比了在3种含不同还原剂的镀液中得到的镀层的形貌、组成、界面扩散及电学性质;探讨了液相激光诱导化学沉积铜的机理。     

维生素C和味精化学镀铜实验探究

经实验探究, 提出一种绿色环保的简易化学镀铜方法。首先利用葡萄糖银镜反应在洁净试管内壁附上一层活性物质, 在此基础上采用维生素C(即抗坏血酸)、味精(即谷氨酸一钠)和硫酸铜等物质按一定工艺操作, 在试管壁上镀上一层光亮的铜镜。本实验适合作为中学化学兴趣实验。     

Comparison of Bottom-up Filling in Electroless Plating with an Addition of PEG,PPG and EPE

The bottom‐up filling capabilities of electroless copper plating bath with an addition of additives, such as polyethylene glycol (PEG), polypropylene glycol (PPG) and triblock copolymers of PEG and PPG with ethylene oxide terminal blocks termed EPE, were investigated by the cross‐sectional scanning electron microscopy (SEM) observation of sub‐micrometer trenches. Though three additives had inhibition for electroless copper deposition, the suppression degrees of three additives were different. EPE‐2000 had the strongest suppression for electroless copper deposition, and the suppression of PEG‐2000 was the weakest. The bottom‐up filling capability of electroless copper was investigated in a plating bath containing different additives with the concentration of 2.0 mg/L. The cross‐sectional SEM observation indicated the trenches with the width of 280 nm and the depth of 475 nm were all completely filled by the plating bath with an addition of EPE‐2000, but the trenches were not completely filled by the plating bath with an addition of PEG‐2000 or PPG‐2000, and some voids appeared. Linear sweep voltammetry measurement indicated that three additives all inhibited the cathodic reduction reaction and the anodic oxidation reaction, and the inhibition of EPE‐2000 was the strongest among three additives, which agreed with that of the deposition rate of electroless copper. Significant differences in surface roughness of deposited copper film were observed by UV‐visible near‐infrared for different suppressors, and the bright and smooth of deposited copper film were in accordance with the inhibition of three additives.     

双光子微纳加工技术结合化学镀工艺制备三维金属微弹簧结构

利用飞秒激光双光子微纳加工技术与化学镀工艺制备了三维金属微弹簧结构.采用扫描电子显微镜(SEM)及选区电子能谱(EDS)对镀层进行了表征,当化学镀时间为15 min时,所得到的镀层厚度约为130 nm.对不同电镀时间下获得的镀层电阻率进行了测定,实验结果表明,当电镀时间为35 min时得到的镀层电阻率约为80×10^-9 Ω·m,仅为银块体材料电阻率16×10^-9 Ω·m的5倍.利用这种方法,我们制备了总长度为28.75 μm、周期为2.93 μm的悬空金属弹簧结构,其中弹簧圈数为9圈,直径为6 μm,弹簧线分辨率为1.17 μm.文中所述的将双光子微纳加工技术与化学镀技术相结合的方法可以实现任意三维微金属结构与器件的制备,在微光学器件、微机电系统(MEMS)及微传感器等领域有着广泛的应用前景.     

Electroless Copper Plating on Liquid Crystal Polymer Films Using Dimethylamine Borane as Reducing Agent

Dimethylamine borane (DMAB) was used in electroless copper plating on liquid crystal polymer (LCP) films. An orthogonal test was applied to optimize the plating condition. With Cu film resistivity as the evaluation index, the optimum plating condition is: 10 g/L of CuSO₄ ? 5H₂O, 14 g/L of EDTA‐2Na, 6 g/L of DMAB, 9.5 of pH value and 50 °C. As pH value increases, the Cu film resistivity decreases and the depo‐ sition rate increases. As temperature increases, the Cu film resistivity decreases first and then increases with a minimum at 50 °C while the deposition rate increases first and then decreases with a maximum at 50 °C. The decreased Cu film resistivity can be attributed to the occurrence of CuO. The adhesive strength of copper layer to LCP film is constant at pH values lower than 8.5 and decreases slightly with the increase in pH value. As temperature increases, the adhesive strength decreases slightly. The decreased adhesive strength with both pH and temperature may be a result of an increased corrosion attack from the bath to the surface of LCP films. Low Cu film resistivity and high deposition rate as well as high adhesive strength can be obtained using DMAB reducing agent.     

A New Approach on the Active Treatment for Electroless Copper Plating on Glass

A new method is described for the electroless deposition of copper onto glass.Commercially available glass slide was modified with γ-aminopropyltrimethoxysilane to form self-assembled monolayer (SAM) on it .Then it was dipped directly into PdCl2 solution instead of the conventional SnCl2 sensitization followed by PdCl2 activation.Experimental results showed that the Pd^2 ions from PdCl2 solution were coordinated to the amino groups on the glass surface resulting in the formation of N-Pd complex.In an electroless copper bath containin a formaldehyde reducing agent,the N-Pd complexes were reduced to Pd^0 atoms,which then acted as catalysts and initiated the deposition of copper metal.Although the copper deposition rate on SAM-modified glass was slow at the beginning,it reached to that of conventional method in about 5min.     

化学镀铜过程混合电位本质的研究

现场测量了铜基和陶瓷基化学镀铜过程混合电位－时间曲线(Emix－t)，成功地检测到了化学镀诱发过程.考察了添加剂和络合剂的浓度以及pH值对Emix－t曲线的影响，结合阴、阳极极化曲线及双电层理论对各种影响因素进行了讨论.新生铜活化的铜基化学镀铜的诱发过程是一个缓慢激活过程,所对应的Emix－t曲线是一个稍微倾斜的台阶，这不同于钯活化的基体的诱发过程.通过对不同活化工艺的Emix－t曲线的比较，发现较高的活化温度能明显减少活化时间，而且还可加速诱发过程，从而提高化学沉积铜的速度.     

以次磷酸钠为还原剂化学镀铜的电化学研究

通过电化学方法研究了以次磷酸钠为还原剂, 柠檬酸钠为络合剂的化学镀铜体系. 应用线性扫描伏安法, 检测了温度、pH值、镍离子含量对次磷酸钠阳极氧化和铜离子阴极还原的影响. 结果表明, 升高温度能够加速阳极氧化与阴极还原过程; pH值的提高可促进次磷酸钠氧化, 但抑制铜离子还原; 镍离子的存在不仅对次磷酸钠的氧化有强烈的催化作用, 而且与铜共沉积形成合金. 该合金有催化活性, 使化学镀铜反应得以持续进行.     

A New Activation Method for Electroless Metal Plating：Palladium Laden via Bonding with Self—Assembly Monolayers

A new activation method has been developed for electroless copper plating on silicon wafer based on palladium chemisorption on SAMs of APTS without SnCl2 sensitization and roughening condition.A closely packed electroless copper film with strong adhesion is successfully formed by AFM observation.XPS study indicates that palladium chemisorption occurred via palladium chloride bonding to the pendant amino group of the SAMs.     

粉末化学镀法制备NiB/NaBETA催化剂及其加氢催化性能

粉末化学镀法制备NiB/NaBETA催化剂及其加氢催化性能;非晶态合金催化剂