Copper Plating Process

Acidic copper electroplating was a wide application in household appliances,daily hardware,electroplating plastics and printed circuit board(PCB).It is well known that additives are required to obtain desirable metallic deposits.Electro copper plating process and mechanism of the composited brightener plating solution was researched comprehensively.The Z brightener was prepared successfully,and the technology and mechanism of copper electroplating was studied.Covering power and throwing power of the bath solutions containing different dyes were measured.The stable polarization curves of the basic plating solution,the composited brightener plating solution and Z brightener plating solution were studied.The technology of copper electroplating of composited brightener was studied.The available conditions of copper electroplating are that H₂SO₄ is 160～200g/L,CuSO₄·5H₂O is 80～100 g/L,N is 0.0010～0.0014g/L, Mis 0.0032～0.0042g/L,PEG-6000 is 0.060～0.100g/L,Cl^-is 40～80 ppm, temperature of plating bath is 10～40℃,current density is 0.8～4.0 A/dm².In available conditions of composited brightener system,the SEM test demonstrates that the surface of copper film is smooth and the crystal is fine.But some area are uneven.The current efficiency of copper plating is 99.65%at 40℃.The available conditions of Z brightener copper electroplating system are that H₂SO₄ is 160～220g/L,CuSO₄·5H₂O is 80～100 g/L,Z brightener is 8～12ml/L,PEG-6000 is 0.400～0.500g/L,Cl^- is 40～80 ppm,temperature of plating bath is 10～40℃,current density is 1～3.5 A/dm².The surface of copper plating film is even and smooth and copper crystal is fine under the above conditions of copper electroplating.The current efficiency of copper plating is 98.7%at 40℃.Covering power and throwing power of the plating solutions containing different dyes are measured.The results show that methylene blue and rhodamine are better than others,and there covering powers are 75.05%and 68.42%,the throwing powers are 85%and 88%,and crystal of the bright coppper deposit is fine and uniform. The stable polarization curves of the basic plating solution,the composited brightener plating solution and Z brightener plating solution were measured.There electric polarization intervals are-16mv～-82.6mv, -25mv～-127mv and -70.18mv～-201.4mv.There potential scales are 66.6mv,102mv and 131.22mv.So the copper surface from Z plating solution is smoothest.Scanning electron microscope testified this result. The electric chemical polarization test testify that Z brightener increases electric chemical polarization,facilitate fine crystal and has bright function.