Sputtering power and deposition pressure effects on the electrical and structural properties of copper thin films

We investigated the effects of sputtering power and deposition pressure on the electrical and structural properties of dc magnetron sputter-deposited copper films on p-type silicon grown at room temperature. Results from our experiments showed that the deposition rate of the copper films increased proportionally with the sputtering power. Sputtering power also affected the structural properties of the copper films through the surface diffusion mechanism of the adatom. From the scanning electron microscopy surface analysis, the high sputtering power favored the formation of continuous film. The poor microstructure with voided boundaries as a result of low sputtering power deposition was manifested with the high resistivity obtained. The deposition rate was found also depending on the deposition pressure. The deposition pressure had the contrary effect on structural properties of copper films in which high deposition pressure favored the formation of voided boundaries film structure due to the shadowing effect, which varied with different deposition pressure.