The Structure of Electroplated and Vapor-Deposited Copper Films

The structures of electroplated and vapor-deposited copper films have been studied by x-ray diffraction. While there was no evidence of stacking faults in any of these films, the electroplated films were characterized by presence of twins, large thickness-dependent microstrains, and small particle sizes. The vapor-deposited films, on the other hand, showed no twins, smaller microstrains, and large thickness-dependent particle sizes. Analysis of the electrical resistivity of the electroplated films indicated that the twin resistivity of copper is, at most, half of the grain-boundary resistivity.