No abstract

Copper (Cu) coatings with a high surface area have attracted significant attention for functional devices due to their high thermal and electrical properties. Pulse-reverse current (PRC) electrodeposition has been introduced to fabricate Cu coatings for a long history, but little attention has been paid to the synergistic effects of anodic and cathodic steps instead of the individual anodic step. The new parameter “artificial exchange current density” (jA) has been demonstrated to quantify the effects of anodic and cathodic currents on the morphology in our previous work. Herein, a key metricthe relative current amplitudethat is positively correlated with jA, is used to further clarify the role of jA in the electrodeposition process. We fabricate Cu coatings with well-dispersed pyramid-like structures and find the relative current amplitude dominates the formation of a larger raised structure at the initial nucleation stage. Moreover, the anodic current can dissolve high-energy planes and achieve a high (111) texture. Afterward, screw dislocation drives the spiral growth of grains, resulting in pyramid-like structures. This study not only enriches our understanding of the artificial exchange current density in PRC electrodeposition but also guides us to achieve Cu coatings with high surface area.