(615b) Electrodeposition of Cu-Sn-In Alloys From Citrate Electrolytes

The electrodeposition of CuSnIn alloys and different combinations of these alloys from a citrate electrolyte are compared and their complexation with citrate species simulated, with a comprehensive mass balance model to assess the different complexed species with variable combinations of the metal ions. The partial current densities were determined for different combinations of metals (i.e., Sn, In, InSn, CuSn, CuIn, CuInSn) using a three electrode configuration with a constant applied potential deposition at room temperature. Experimental findings included the following: (1) the reaction rate of Sn was enhanced when codeposited with Cu and CuIn, (2) the surface morphology of copper containing alloys were rougher than the elemental deposits or alloys without Cu, and (3) the ratio of Sn:In in the deposit was altered when Cu was present. The enhancement was associated with an increase in surface area and a kinetic effect, but not due to changes in the metal-citrate species.