Chih Ming Chen¹, Hsuan Lee¹; ¹National Chung Hsing University

Copper is widely used as an interconnect, trace, and metallization in microelectronic products due to good electrical and thermal properties. Electroplating is an economical method to deposit copper. Successful electrodeposition of copper depends on the molecular interaction among various organic additives and optimized plating current density. Impurity incorporation from organic additives or their derivatives usually occurs along with the atomic deposition of copper. Two common additives, suppressor and accelerator, and chlorine ions were added in the plating solution along with the basic electrolytes (sulfuric acid and cupric sulfate) to fabricate the copper deposits. The plating current density was also adjusted as an electroplating parameter in addition to the change of the additive formula. The results showed that the additive formula and plating current density had a significant effect on the grain microstructure of the copper deposits and the interfacial reactions of the resulting copper/solder joints.