十二烷基硫酸钠（SDS）对铜电沉积行为的影响

Effect of sodium dodecyl sulfate(SDS) on copper electrodeposition behavior

摘要:

在酸性体系中采用阴极扫描伏安和计时电流等电化学测试方法，研究添加十二烷基硫酸钠（SDS）对铜电沉积过程的影响机理。结果表明：SDS的添加使沉积电位正移，降低了阴极极化。SDS浓度低于临界胶束浓度1g/L时，铜的成核弛豫时间延长，形核速率降低。SDS浓度高于临界胶束浓度时，形成SDS球状胶束，铜的成核弛豫时间减少，形核速率加快。铜晶核形成过程符合Scharitker?Hill 三维成核/生长机制，当SDS为1g/L时，在-0.2V的低过电位区，铜结晶按渐进成核方式进行，在-0.23--0.28V的高过电位区，铜结晶按瞬时成核方式进行。而当SDS为0.5g/L时，铜在-0.2V--0.25V的低电位区和在-0.28V的高电位区均符合渐进成核。

Abstract:

Electrochemical test methods such as cathodic scanning voltammetry and chronoamperometry were used in the acidic system to study the influence mechanism of sodium dodecyl sulfate (SDS) on the electrodeposition process of copper. The results show that the addition of SDS causes the deposition potential to shift positively and reduces the cathodic polarization. When the SDS concentration is lower than the critical micelle concentration of 1g/L, the nucleation relaxation time of copper is prolonged and the nucleation rate is decreased. When the concentration of SDS is higher than the critical micelle concentration, SDS spherical micelles are formed, and the nucleation relaxation time of copper is reduced and the nucleation rate is accelerated. The copper nucleation process conforms to the three-dimensional nucleation/growth mechanism of Scharitker?Hill. When the SDS is 1g/L, in the low overpotential zone of -0.2V, the copper crystals proceed in a progressive nucleation mode at -0.23-0.28V. In the high overpotential zone, the copper crystals proceed in a progressive nucleation mode. When the SDS is 0.5 g/L, copper conforms to the progressive nucleation in the potential region of -0.2V to -0.28V.