Effect of substrate orientation on film properties using AC reactive magnetron sputtering

CrN coatings were prepared by magnetron sputtering with target-substrate orientations varying between 0° and 90° and N2 flow rates of 43, 40 and 30 sccm. The coatings were deposited on (111) Si wafers at a chamber pressure of 0.2 Pa for 1 h. Initial results indicate that the target-substrate orientation to the incoming flux of ionized species affects the microstructure, phase and preferred orientation of the crystallites in Cr–N coatings. The SEM studies of the film morphology showed a distinct change from coarser, less dense coatings to smooth, dense and fine-grained morphologies as a function of the changing orientation of the substrate, while the cross-sectional micrographs showed a columnar growth of the crystallites independent of substrate orientation. When the target-substrate angle was varied from 0° to 90°, the average roughness (Ra) decreased from 78 to 23 nm. We report on the details of the microstructural and chemical characterization of the films deposited in this study.