氯离子在局部电化学中对铜电沉积的影响

Effect of chloride ions on copper electrodeposition in local electrochemistry

局部电化学沉积(LECD)制造金属微结构是一种非常便捷和经济的方法。用20μm直径微阳极来研究Cl^(-)浓度在LECD上对铜微柱形貌、直径、沉积速率等的影响。Cl^(-)使铜离子先还原为亚铜离子,然后再还原成铜,能促使铜微柱沉积速率提高,进而可调控铜微柱形貌质量,提高沉积效率。在铜还原过程中氯化亚铜会在铜微柱表面形成,并发生歧化反应,使铜微柱表面产生孔隙、粗糙形貌,而过高Cl^(-)浓度会形成氯化亚铜结晶,增大铜微柱直径。受高电流密度和高氢离子浓度影响,在铜微柱内部无法沉淀氯化亚铜。Cl^(-)浓度所对铜微柱形貌、沉积速率等的影响为Cl^(-)与其它添加剂在LECD上协同应用提供了参考。

Local electrochemical deposition(LECD) is a very convenient and economical method for manufacturing metal microstructures.The effects of Cl^(-)concentration on the morphology,diameter and deposition rate of copper microcolumn on LECD are studied by a microanode with a diameter of 20 μm.Cl^(-)causes the reduction process of copper ions to become cuprous ions,and then to be reduced to copper.Cl^(-)has the effect of accelerating the deposition of copper microcolumns,thereby regulating the morphology and improving deposition efficiency of copper microcolumn.It also causes the cuprous chloride to cover the surface of copper microcolumn.Due to the disproportion reaction of cuprous chloride,pores and rough morphology are formed on the surface,and the cuprous chloride crystals also increase the diameter of copper microcolumn.Because of high current density and high hydrogen ion concentration,cuprous chloride cannot be formed inside the copper microcolumn.The effect of Clconcentration on the morphology and deposition rate of copper microcolumn provides a reference for the synergistic application of Cl^(-)and other additives on LECD.