No abstract

We report and contrast both the electrical resistance and the microstructure of copper thin films deposited in an oxygen containing atmosphere by ion-beam and dcmagnetron sputtering. For films with thicknesses 5 nm or less, the resistivity of the Cu films is minimized at oxygen concentrations ranging from 0.2% to 1% for dc-magnetron sputtering and 6% to 10% for ion beam sputtering. Films sputtered under both conditions show a similar decrease of interface roughness with increasing oxygen concentration, although the magnetron deposited films are smoother. The dc-magnetron produced films have higher resistivity, have smaller Cu grains, and contain a higher concentration of cuprous oxide particles. We discuss the mechanisms leading to the grain refinement and the consequent reduced resistivity in both types of films.