Investigation and Electrodeposition Rate Optimization of Au–Cu Alloy Co-Deposition

Abstract

In the present study, influence of effective parameters on electrochemical deposition rate optimization of alloy Co-deposition. Main parameters in this method include current density direct, concentration of Au, Cu ions, solution pH, agitation, and effect of additive that are effectively optimized using “one-factor-at-a-time” method to achieve Au–Cu electrochemical alloy deposition with 18 carat (750 part in a hundred part Au in weight basis, according to the carats of formal national and international standards) and proper electrodeposition rates of 6 mA/cm2, 6 gr/lit, 55 gr/lit, 24 gr/lit, 66 °C, 12.3, 100 rpm and 1 gr/lit, respectively. Scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDS), inductively coupled plasma-optical emission spectrometry (ICP-OES), and X-ray fluorescence (XRF) characterization methods were used in study of electrochemical deposition influence on cross sections of the deposited layers. In this method, results indicates that electrodeposition rate in optimum conditions and approximate karat of 750 K, with direct current (6 mA/cm2) in 4 hours is 0.841 μm/min. In this work, deposition rate has increased significantly compared to commercial methods 1 μm/3–7 min. Percentages of Au in deposited layers were compared through inductively coupled plasma-optical emission spectrometry (ICP-OES) and X-ray fluorescence (XRF) characterization methods, but ICP-OES is a more accurate method.