High resolution electron microscopy of CrN–TiN thin films grown on Si(100) by magnetron sputtering

CrN–TiN thin films were deposited as successive, alternating layers on Si(100) substrates using a closed field unbalanced reactive magnetron sputtering method (CF-UBRMS) at various substrate biases (Vb) and substrate rotation speeds. High resolution electron microscopy (HREM) study showed that the nanostructural characteristics of the films depend on the growing conditions. For the case of substrate bias Vb = − 50 V and high rotation speed of the substrate, the film is polycrystalline with no preferential growth mode, while for lower speeds two nanocrystalline layers are formed with preferential growth orientations: [100]nitrides//[100]Si in the first zone and [111]nitrides//[100]Si in the second one. Epitaxial growth is observed sometimes locally in grains of the first zone. The multilayer character of the films was partially preserved only for films grown with the substrate at floating potential and low substrate rotation speed. For a higher speed, the growth takes place also with the two-zone growth mode.