In this work, 3-mercapto-1-propanesulfonate (MPS) with one sulfhydryl (–HS) group and 2,3-dimercapto-1-propanesulfonate (DMPS) with two –HS groups were used as model additives to reveal the function of –HS group during copper plating. Chronopotentiometry was employed to characterize the different electrochemical behaviors of the two model additives. It indicated that DMPS showed stronger accelerating effect than MPS in the plating bath containing Cl − , which could be attributed to its enhanced adsorption caused by two –HS groups. The pre-adsorption and desorption experiments demonstrated the synergistic effects and competitive adsorption between Cl − and the model additives. Moreover, the accelerating mechanism was investigated by cyclic voltammetry combined with rotating ring-disk electrode (RRDE), demonstrating MPS could accelerate the rate-determining step (RDS) of copper deposition only if Cl − was present, whereas DMPS could enhance the RDS whe...

中文翻译：

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巯基（–HS）基团在铜镀微孔填充过程中的作用

在这项工作中，带有一个巯基（–HS）的3-巯基-1-丙磺酸盐（MPS）和带有两个–HS基的2,3-二巯基-1-丙烷磺酸盐（DMPS）被用作模型添加剂，以揭示–镀铜时的HS组。计时电位法用于表征两种模型添加剂的不同电化学行为。结果表明，DMPS在含Cl-的镀液中显示出比MPS更强的加速作用，这可能是由于两个-HS基团引起的吸附增强。预吸附和解吸附实验表明，Cl-和模型添加剂之间具有协同作用和竞争性吸附。此外，通过循环伏安法结合旋转环盘电极（RRDE）研究了加速机理，