Analysis of Abnormal Grain Growth on Electrodeposited Copper Film

Abnormal grain growth occurring on an electrodeposited copper film was investigated for defect prevention during electrolytic copper foil production. An electrodeposited copper film was formed on a titanium substrate. Then abnormal grain growth was observed using scanning electron microscope equipped with an energy dispersive X-ray spectrometer (SEM-EDX) and X-ray diffraction (XRD). Generation of abnormal grains depended on the method of pretreatment of the titanium substrate. Titanium particles generated by mechanical polishing during the pretreatment process were related to the abnormal grain growth. The preferred orientation of copper near titanium particle differed from that in the other parts of the film. Titanium particles were found to be involved in abnormal grain growth.