Morphology and properties of sputtered HfN layers as a function of substrate temperature and sputtering atmosphere

HfN layers were prepared by reactive rf-magnetron sputtering onto polished flat high speed steel (HSS) surfaces. Rectangular samples were mounted on a special holder providing temperatures in the range of 775 to 300 K along the length of the sample. The HfN layers were deposited at various total pressures and different N2/Ar ratios. The film morphology and composition was studied by scanning electron microscopy (SEM) and Auger electron spectroscopy (AES), respectively, and correlated with mechanical properties like microhardness and adhesion. The results are discussed with respect to the sputtering conditions