添加剂对酒石酸盐镀铜的影响

Effects of additives on tartrate copper electroplating

研究了一种无氰碱性镀铜工艺。运用循环伏安法和扫描电子显微镜研究了配方中三乙醇胺(4mL/L)、硝酸铵(1.5g/L)、亚胺类物质hg01(1mL/L)和吡啶类物质hg02(0.5g/L)等4种添加剂的作用。结果表明:三乙醇胺能改善低电流密度处镀层质量;硝酸铵与铜离子结合能在较宽电流密度范围内参与阴极还原反应,有效抑制析氢反应;hg01优先吸附在阴极高电流密度处与铜离子产生强配合作用,能提高镀液的分散能力,有利于产生细微晶粒;hg02能在电极表面吸附,增大了铜沉积过程的极化作用,有效改善了中电流密度区镀层的整平性和脆性。X射线衍射研究表明,该铜镀层表现出(111)晶面的择优取向。该工艺具有良好的镀液及镀层性能,镀层厚度中等,适合用于铁基片上打底。

A non-cyanide alkaline copper electroplating technology was studied. The role of 4 additives including triethanolamine （4 mL/L）, ammonium nitrate （1.5 g/L）, imine compound hg01 （1 mL/L） and pyridine compound hg02 （0.5 g/L） was studied by cyclic voltammetry and scanning electron microscopy. The results showed that triethanolamine improves the coating quality in low current density area. Ammonium nitrate takes part in cathodic reduction over a wide range of current density and effectively restrains hydrogen evolution. Hg01 is preferentially adsorbed on cathode surface at high current density, where a strong complexation with copper ion occurs leading to an enhancement of the throwing power of bath and to the formation of fine and uniform grains. Hg02 is adsorbed on electrode surface, raises the polarization of copper deposition and improves leveling ability and brittleness in middle current density area. X-ray diffraction patterns showed that copper deposit has preferential orientation with （111）. The process has advantages of good properties of bath and deposit and produces moderate thickness of deposit. It is suitable for forming a sublayer on iron substrate.