Additive for reducing voids after annealing of copper plating with through silicon via

摘要

An additive for reducing voids after annealing of copper plating with through silicon via. The additive contains by weight percent: 0.05-1% of one or more of quaternized polyethylene imine and derivatives thereof having different molecular weights, and 1-10% of polyethylene glycol with an average molecular weight of 200-20000. The additive is used in combination with an electroplating solution of a copper methyl sulfonate system. The electroplating solution of a copper methyl sulfonate system contains 1-5 ml/L of the additive by volume ratio. The electroplating solution of a copper methyl sulfonate system contains by mass volume ratio: 50-110 g/L of copper ions, 5-50 g/L of methanesulfonic acid and 20-80 mg/L of chlorine ions. The electroplating solution also contains by volume ratio: 0.5-5 ml/L of accelerator, 5-20 ml/L of inhibitor and 5-10 ml/L of levelling agent. The additive for reducing voids after annealing of copper plating with through silicon via provided in the present invention can solve the problem of micro-voids between grain boundaries after high temperature annealing of copper plating.