不同聚合度壬基酚聚氧乙烯醚在酸性光亮镀铜中的应用

Application of NP(EO)_n with different polymerization degrees in acid bright copper plating

为研究壬基酚聚氧乙烯醚(NP(EO)_n)可用作酸性光亮镀铜载体光亮剂的原因以及不同聚合度NP(EO)_n对铜沉积过程的动力学参数和沉积层表观形貌的影响,以NP-10、NP-15、NP-20、NP-40配合Cl^--DPS作为50℃CuSO_4-H_2SO_4镀液的添加剂,采用电势扫描交流阻抗法研究NP(EO)_n在电极表面吸附双电层的形态,采用线性电势扫描和计时电流法研究NP(EO)_n对电沉积过程的影响,并采用扫描电子显微镜和X射线衍射表征沉积层的形貌及晶面取向。结果表明:NP(EO)_n在电极表面的吸附层阻碍Cu^(2+)的扩散,增强极化,细化晶粒;由于NP(EO)_n吸附层亲水链长度不同,对Cu^(2+)的屏蔽程度不同,对电沉积影响各异;NP(EO)_n链长越长,沉积层的形貌越佳。

To study the reason why nonylphenol ethoxylates （NP（EO）n） can be used as the brightener in acid bright copper plating and effect of NP（EO）n with different polymerization degrees on kinetic parameters of copper deposition and morphology of deposits, NP-10, NP-15, NP-20 and NP-40 were used with Cl--DPS as additives in CuSO4-H2SO4 at 50 ℃. Adsorption morphology of NP（EO）n in electric double layer on electrode and influence of NP（EO）, on electrodeposition were studied by potential scan electrochemical impedance spectroscopy, linear sweep voltammetry and chronoamperometry, respectively. The morphology and crystal orientation of deposits were characterized by scanning electron microscopy and X-ray diffractometry. The results show the adsorption layer of NP（EO）n on electrode blocks the diffusion of Cu2＋, enhances the cathode polarization and refines the grain size. NP（EO）n shows different effects on eleetrodeposition due to the different length of hydrophilic chain. In general, the longer the length of NP（EO）, chain, the better the morphology of deposit.