Substrate effect on texturized microstructures in NiCr thin films
Abstract NiCr thin films with a composition of 40at.%Ni and 60at.%Cr have been sputter deposited on stainless steel and glass substrates. The microstructure and composition have been analysed by scanning electron microscopy, Rutherford-backscattering spectroscopy, X-ray diffraction and transmission electron microscopy. Evidence is found of the metastable σ phase and of the two terminal solid solutions α-Cr and γ-Ni. The microstructure is characterized by a cubic close-packed lattice alternating with a hexagonal one within the same grains, resulting in a stacking fault presence. Evidence is found that the films have a fibre texture with the axis tilted 20° with respect to the surface normal and that different substrates induce different fibre axis orientations: (111) for the stainless steel substrate and (110) for the glass one. This characteristic could be interpreted in terms of different relative concentrations of the two terminal solid solutions due to the different substrate temperature during thin film deposition.