The Effects of Dissolved Oxygen in the Bath on the Properties of Electroless Copper Plating

Electroless copper plating in the PCB industry is used for seed layer formed for electrolytic plating on non-conductivity substrate and through hole plating. Electroless copper plating has various side reactions such as disproportionation reaction. And then the electroless copper bath was decomposed due to copper precipitation. To prevent such self-decomposition, stabilizers were added or bath was air agitated. In this study, the effect of various gases, such as nitrogen, oxygen and air, on the properties of electroless copper layer were investigated. Open circuit voltage (OCV), polarization plots, potentio/galvanostat analyses were conducted to investigate the effect of purged gas.