Effect of pulse and pulse-reverse current on surface morphology and resistivity of electrodeposited copper

Recently, requirement for the ultra thin copper foil increases with smaller and miniaturized electronic components. In this study, we evaluated the surface morphology, crystal phase and surface roughness of the copper film electrodeposited by pulse method without using additives. Homogeneous and dense copper crystals were formed on the titanium substrate, and the optimum condition was 25% duty cycle. Moreover, the surface roughness(Ra), 0.295 μm, is the smallest value in this condition. It is thought that this copper foil is good for electromigration inhibition due to the preferential crystal growth of Cu (111).