Microstructural control of Cr–Si–N films by a hybrid arc ion plating and magnetron sputtering process

The microstructural evolution of Cr–Si–N films deposited by a hybrid arc ion plating and magnetron sputtering process was investigated by varying the sputtering power of Si target and substrate bias voltage. Detailed nanocomposite microstructures of the films were studied by high-resolution transmission electron microscopy. The results indicated that the incorporation of Si into the growing CrN films at 0 V led to the formation of a nanocomposite containing CrN nanocolumns embedded in amorphous SiNx matrix or near-amorphous microstructure. For the films having a Si content of ∼10 at.% and ∼15 at.%, a negative bias voltage of −50 V resulted in the aggregation of nanocolumns in the amorphous matrix. Further increase of negative bias voltage to −250 V led to the formation of a three-dimensional CrN/a-SiNx nanocomposite microstructure. The mechanism of microstructure evolution is discussed by considering the thermodynamic and kinetic factors.