Structure, phase evolution, and properties of Ta films deposited using hybrid high-power pulsed and dc magnetron co-sputtering

Crystalline phase and microstructure control are critical for obtaining desired properties of Ta films deposited by magnetron sputtering. Structure, phase evolution, and properties of Ta films deposited by using hybrid high power impulse magnetron sputtering (HiPIMS) and direct current magnetron sputtering (DCMS) under different fractions of DCMS power where Ta ion to Ta neutral ratios of the deposition flux were changed are investigated. The results revealed that the number of Ta ions arriving on the substrate/growing film play an important role in structure and phase evolution of Ta films. It can effectively avoid the unstable arc discharge under low pressure and show a higher deposition rate by hybrid high power impulse magnetron sputtering (HiPIMS) and direct current magnetron sputtering (DCMS) compared with only high power impulse magnetron sputtering (HiPIMS). Meanwhile, the high hardness α-Ta films can be directly deposited by hybrid co-sputtering compared to those prepared by direct current magnetron sputtering (DCMS). In the co-sputtering technology, pure α-Ta phase film with extremely fine, dense and uniform crystal grains were obtained, which shows smooth surface roughness (3.22 nm), low resistivity (38.98 μΩ·cm) and abnormal high hardness (17.64 GPa).