The influence of sputtering pressure and film thickness on metal resistivity

Electrical resistivity is an important indicator of metal thin film quality. In this study, the influence of argon working pressure on the properties of metal thin films was evaluated, and the thickness effect on the resistivity of metal thin films was investigated. The sputtered thin film resistivity performances of seven metals as a function of argon pressure were measured, and the results turned out that the argon pressure was vital to film quality. Further investigation on sputtered chromium thin films using XRD, SEM and XPS revealed that the argon pressure influences the microstructure of sputtered metal thin films. Different microstructure is the reason for different resistivity performances, and John Thornton's "Zone Model" explains all these behaviours well. The resistivity of aluminum and chromium thin films with thickness from 15 to 150 nm were compared, the resistivity change significantly. The scaling trends are different for different metals.