Potentiostatic Cu-Zn Alloying for Polymer Metallization Using Medium-Low Temperature Ionic Liquid Baths

Abstract

Cu-Zn alloy metallization of a non-conductive epoxy substrate was demonstrated through successive electrochemical processes: (i) conventional electroless Cu deposition on the substrate using an aqueous bath, and (ii) electrochemical alloying of the resulting Cu layer with Zn by a reduction-diffusion (RD) method using an ionic liquid bath at 150 {degree sign}C. The resulting Cu-Zn alloy layers were adhe-sive and were uniformly grown by maintaining the surface mor-phology of the initial electroless Cu. The Cu-Zn phases, i.e. γ-Cu5Zn8, β′-CuZn, and/or α-Cu(Zn), which define the color of the layers were dependent on applied potential during the RD alloying.