化学镀铜活化浆料的制备及催化机理

Preparation of Activation Slurry for Electroless Copper Plating and Analysis of Its Catalytic Mechanism

为了能使绝缘基材高效、低成本地实现线路的金属化,制备了一种含银的化学镀铜活化浆料,将其涂在PET(聚对苯二甲酸乙二酯)薄膜上再进行化学镀铜。通过红外光谱、扫描电镜(SEM)以及结合力、导电性、开路电位-时间曲线测量等分析了活化浆料的分子结构以及化学镀铜过程中试样的表面形貌、性能,并探讨了活化浆料的催化机理等。结果表明:Ag+与聚氨酯树脂主链-NHCOO-基团中的N,O形成配位键;化学镀铜过程先得到离散均匀的铜颗粒,随时间延长最终得到均匀致密的铜层;银含量越大,缓慢生成铜活性中心的诱导时间越短,浆料活性越高;该工艺可得到结合力、导电性良好的电路图案,可在全印制电子技术中推广应用。

A kind of silver-containing activation slurry for electroless copper plating on insulating substrate was formulated.The structure of the activation slurry was analyzed by Fourier transform infrared spectrometry.The morphology of Cu coating was analyzed by scanning electron microscopy.Moreover,the adhesion,electrical conductivity and electrochemical open circuit potential-time curves of the Cu coating were measured,and the catalytic mechanism of the activation slurry was investigated.It was found that Ag + was coordinated with N and O atoms of-NHCOO-in polyurethane resin backbone.In the early stage of electroless Cu plating,uniformly distributed Cu particulates were formed on the surface.An even and dense Cu coating was finally obtained at extended plating duration.Besides,the induction time of Cu deposition was shortened and the catalytic activity of the activation slurry was increased with increasing Ag + concentration.The present electroless Cu plating process could prepare coatings with perfect adhesion and electrical conductivity,showing potential application for fully printed electronic technology.