Copper Electroplating in Alkaline Bath Containing Novel Brightening Agent

A novel combinatory brightening agent was used for Cu electropla-ting in an alkaline bath.The effect of composition of the brighte-ning agent on the polarization ability of the plating solution was examined by making use of polarization curve measurement,Hell Journal of Materials Protection cell test,and scanning electron microscopy and X-rav diffraction analysis.At the same time,the bonding strength,morphology,composition,and crystal structure of the electroplated Cu coating were analyzed.It was found that the four kinds of additives intro-duced into the combinatory brightening agent were all able to in-crease the polarization ability of the plating solution and func-tioned in different ways during Cu electroplating.The Cu coating obtained at a current density of 1～ 10 A/dm2 was composed of fine Cu grains.Moreover,when the Cu coating was relatively thinner,it tended to grow with preferential orientation along(111) and(220) planes while the coating with a moderate thick-ness tended to grow with preferential orientation along(111) plane.