Electrodeposition of FeCoRu Alloy

Abstract

The electrodeposition of FeCoRu alloys was studied with rotating disk electrode, surface pH measurements and galvanotstatic plating in a paddle cell. The Ru deposition does not occur until a potential of -0.9 V versus MSE is reached, much higher than the literature reversible potential. In the FeCoRu system, the presence of Ru inhibits the Fe plating rate but exerts no effect on the Co. Surface pH measurements further confirmed the high potential for Ru deposition and a significant hydrogen evolution reaction was observed causing enhanced local agitation at the electrode surface. The effect of complexing agent was also studied for FeCoRu plating. The presence of citrate, tartrate or histidine, were all found to decrease the current efficiency at the conditions of study. While the decrease observed in the citrate and tartrate cases was probably due to the buffering effect, which increases the hydrogen evolution current, histidine was believed to complex with metal cations and to inhibit the metal deposition.

FeCo/Cu and FeCo/Ru Laminated Structures by Electrodeposition

“…From the studies of pure Ru plating from this RuCl 3 chemistry, the Ru deposition does not occur until the potential reaches -0.9 V vs. MSE or the current reaches -9 mA/cm 2 . [12] In the laminated structures, Ru layer was electrodeposited at -10 mA/cm 2 with a plating rate of 0.2 nm/sec. Figure 6.…”

“…Single bath plating can eliminate the handling time and minimize the corrosion or displacement in the two bath plating method. Since the Ru deposits only at a highly negative potential, close to the FeCo reversible potentials, [12] a single bath for pulse plating the FeCo(Ru)/Ru structure was not obtained. Laminated FeCo(Cu)/Cu films were plated using a single electrolyte shown in the experimental and Figure 6 shows the MH loops of the deposits.…”