Effects of DPS on Surface Roughness and Mechanical Properties of Electrodeposited Copper Foils

Abstract The roughness and mechanical properties of ultra‐low profile electrolytic copper foil seriously affect and restrict its application in high‐frequency/high‐speed printed circuit boards and Li‐ion batteries. herein, the electrochemical behavior and mechanism of 3‐ N , N ‐dimethylaminodithiocarbamoyl‐1‐propanesulfonic acid (DPS), alcohol sulfur propane sulfonate (HP), and hydrolisis animal protein (HAP) as composite additive for electrodeposition of copper foil is reported. Meanwhile, the effect of DPS on the roughness and mechanical properties of electrolytic copper foils is also investigated. The results show that addition of DPS further reduces the surface roughness of copper foil, due to the enhanced competitive adsorption of DPS with HAP, arising from the synergistic interaction between DPS and HP. additionally, the DPS can also reduce the grain size of copper foil and change the preferred orientation of the crystal plane, thereby improving the tensile strength of copper foil. The surface roughness of copper foil is as below as 1.02 µm. The tensile strength and the elongation of copper foil reach 386.5 MPa and 3.7%, respectively. Furthermore, the as‐obtained copper foil has high corrosion resistance and low resistivity. Therefore, the novel composite additive can pave the way for improving the quality of electrodeposited copper foil and realizing the possibility of widespread application.