Abstract
Fatigue fracture properties of electroplated copper thin films were measured under uni-axial stress loading. Two kinds of electroplated films were prepared for fatigue test. One was a commercial film mainly used for interconnections in printed wiring boards. The other film was grown on stainless steel substrate by using acid copper sulfate bath including no additive agent. The fatigue fractured surfaces were observed using SEM. It was found that the fracture mode of the films was quite different with each other. One was ductile and the other was brittle. In addition, the fatigue strength of the film grown on the stainless steel was about 1.5 times higher than that of .the commercial film. This was because of the difference of the micro texture between the two kinds of films.
