Changes in Electrical Properties of Copper-Plated Layer by Organic Additives on High Current Density

Abstract

Electroplating has many economic advantages in producing copper foils. The easiest way to manufacture electroplated copper foil with various properties is to add appropriate additives. This study evaluated the surface properties, mechanical and electrical properties of copper foil electroplated in electrolytes containing the leveler JGB (Janus Green B). When the leveler JGB was added as an additive, Cu crystals were distributed uniformly on the surface layer in an initial nucleation process. In the JGB-free group, dents and pinholes were observed on the surface of the electroplated Cu foil. Such surface defects were reduced with the addition of JGB. Surface roughness was decreased by 68% in the samples electroplated in electrolytes with 10 ~ 40 ppm JGB, when it is compared with a JGB-free sample. It was observed that the priority growth direction of crystal texture changed from (200), (111) to (220). Elongation decreased by 59%, while the tensile strength increased by 157% due to a decrease in crystal size by 69%. With the addition of 0 ~ 40 ppm JGB, resistivity increased due to the decrease in crystal size and changes in the crystal texture. Based on a linear regression approximation between 0 and 40 ppm the value of R2 was 91.4%. There was no statistically significant difference between 40 and 60 ppm, and the resistivity was 37.7% higher than in the JGB-free sample. Key words: JGB, copper, electroplating, mechanical property, resistivity