The Research Of The Technics Of Non-dye Acid Copper Electroplating

A new copper electroplating bath is found.MN(M,N,SPS,PE) and its substituent technics are researched by the Hull Cell Test. After a great many equipments, a basic prescription is found. It is made up of M(0.0003~0.0010g/L),SPS(0.0320~0.0600g/L),PE(0.0480~0.1000g/L),H1(0.0160~0.0300g/L), PN(0.0200~0.0400g/L), AESS(0.0100~0.0200g/L). M is a good brightener in high current density area. SPS is a grain refiner, can improve the current density. H1 can replace M and N; its conjugate ring structure can improve cathodic polarization. It is better than N as a leveler. PE is a surface active agent, as a wetting agent and carrier in acid copper electroplating. PN and AESS are both strong brightener and leveler. PN is a cationic polymer, which makes competitive adsorption with copper ion in cathode surface and gets in the way of copper ion's deposition. Based on this prescription, DPS(0.0300~0.0600g/L), S(0.1200~0.2400g/L), P(0.0600~0.1000g/L) and I(0.0060~0.0120g/L) are added in. DPS is similar with SPS, its amino and acyl form a conjugated bond, which enhance the adsorptive power at cathode surface. It also widen the bright range in low current density area. I is a brightener in low side, which can widen the bright range. S and P are both surfactant, can improve cathodic polarization and other additive agent's leveling ability.The result of the electropotential scan show that the cathodic polarization overpotential and polarizablity of Q(our prescription) is between MN and EPI(the best prescription abroad). Q's capacity for blocking copper ionic discharge is also between them. Accordingly, Q should be improved more.