Effect of fluorosurfactant on copper-tin reduction from methanesulphonic acid electrolyte

In this study, methanesulphonic acid electrolytes have been used to electrodeposit copper-tin alloys of different compositions to examine the effect of a fluorosurfactant additive on deposit composition. Experiments have been carried out at a rotating cylinder Hull cell as it allows the deposition of many alloy compositions over a wide range in a single experiment. The relative amounts of tin and copper in the deposit were controlled by fixing the ratio of copper to tin in the electrolyte as well as the addition of hydroquinone and a non-ionic fluorosurfactant additive. It was found that without the surfactant, metal oxides with a tin content of 35 wt-% were deposited. The addition of the surfactant eliminated metal oxides and deposits with a tin content of up to 85 wt-% could be plated.