The effect of thermal oxidation of 316 L stainless steel cathode blanks used in copper electrodeposition was studied. Current and potential step experiments were performed to evaluate electrochemical changes caused by the oxidation treatments. SEM and AES were used to characterize the stainless steel substrates and the deposited copper films. Particular emphasis was given to the initial stages of copper nucleation and growth. The copper electrocrystallization process was strongly influenced by the temperature employed in oxidizing the stainless steel. Dense, uniform and fine copper nuclei were obtained on the stainless steel substrate oxidized in air at 200 degrees C and 300 for degrees C 3 h. The copper nucleation density and uniformity decreased considerably on substrates treated at 500 degrees C and 600 degrees C. Attempts were made to identify changes in the mechanism of copper nucleation on the various oxidized stainless steel substrates using models developed by Thirsk and Harrison.