Effects of thickness on microstructure and properties of Niobium films deposited by DC magnetron sputtering

In this paper, Nb films with different thicknesses were fabricated by DC magnetron sputtering. The deposition rate, surface roughness, crystal structure of Nb films at different sputtering thicknesses were studied, and the RMS roughness of the Nb film was in 1×10-1 nm level. The stress and preferred orientation of Nb films were studied. The AFM images showed that the films were compact and smooth. The X-ray diffraction results indicated that Nb films were body-centered cubic structure with a preferred orientation of (110). The stress in the Nb films increased with the increase of the thickness of Nb film and reached a maximum of 1.015 1 GPa when the thickness was 200 nm, after that the stress decreased with the increase of the thickness of the Nb film.