【摘要】 以低主盐浓度、弱碱性、复合配位的柠檬酸盐电子电镀铜新体系为研究对象,阐明了新型添加剂XNS(聚胺类化合物和含氮化合物的混合物)在新电沉积铜体系中的作用.恒电流沉积实验结果表明,添加剂XNS能够提高铜沉积的电流效率,特别是在2.0 A/dm~2电流密度下,添加剂XNS使铜沉积电流效率达到95.4%,提高了17.5%.电化学实验的结果表明,添加剂XNS改变了铜沉积的电极过程,由原来的两步单电子还原过程[Cu(Ⅱ)+e→Cu(Ⅰ)+e→Cu]转变为一步两电子还原过程[Cu(Ⅱ)+2e→Cu].虽然添加剂XNS呈现促进铜电沉积的特征,即还原电流增大,但铜镀层颗粒却更细小、更致密均匀.在2.0 A/dm~2电流密度下,铜镀层晶体结构由无添加剂时的(111)晶面重构为高择优取向的(200)晶面.更多还原

【Abstract】 Electronic copper electroplating has important applications in the advanced electronic manufacturing industry.In this work,the effects of the additive XNS(a mixture of polyamine and nitrogen-containing compounds)on the coating structure in the novel,weakly alkaline and citrate-based multi-coordination system for copper electronic electroplating with low concentration of main salts(10 g/L copper sulfate)was investigated.The constant current deposition experiments indicate that the additive XNS can increase the current effi-ciency of copper electrodeposition,which achieves 95.4%at a current density of 2.0 A/dm~2and increases by17.5%comparing to the electroplating system without XNS.Electrochemical experiments prove that the addi-tive XNS can change the cathodic reduction of Cu（Ⅱ）cations,i.e.,in presence of XNS which is a one-step two-electron process[Cu（Ⅱ）+2e→Cu],and in absence of XNS which is a two-step one-electron processes[Cu（Ⅱ）+e→Cu（Ⅰ）+e→Cu],and improves the reduction current density of Cu electrodeposition.Although ad-ditive XNS can accelerate copper electrodeposition rate,the coating surface of Cu becomes much finer and neater.At the current density of 2.0 A/dm~2,the crystal structure of copper coating is reconstructed from Cu(111)facet to Cu(200)facet,presenting highly preferred crystal orientation in the presence of XNS.更多还原