关键词: 化学镀铜, 次磷酸钠, 2,2′-联吡啶

Abstract: In the bath of the electroless copper plating using sodium hypophosphite as reductant,the effects of 2,2′-dipyridine on the deposition rate,anodic oxidation of sodium hypophosphite,cathodic reduction of copper ions,surface morphologies,structure and the existing status of the deposit components were examined.The results showed that,2,2′-dipyridine hindered the electroless deposition.Experiments of liner sweep voltammetry(LSV) indicated that,as the addition of 2,2′-dipyridine to the electrolyte,the oxidation peak potential of sodium hypophosphite shifted to a more negative value but the peak current decreased;the reducing peak potential of copper ions moved to a more negative value whereas the peak current increased.Scanning electron microscope(SEM)、energy dispersive spectroscopy(EDS)、X-ray diffraction(XRD) and X-ray photoelectron spectroscopic(XPS) experiments displayed that,the additive caused the deposit in the compacter,brighter and lower nickel content.the deposit was Cu-Ni alloy in face-centered cubic structure without obvious crystal face preferred orientation.the copper and nickel in the deposit were in metal state,and the weight content of phosphorus was less than 0.05%.

Key words: electroless copper plating;sodium hypophosphite, 2,2′-dipyridine