Effect of the substrate thermal expansion coefficient on the thermal residual stresses in W-Si-N sputtered films

摘要

In this work, W-Si-N films were deposited by sputtering onto three substrates with different thermal expansion coefficients. It was possible to demonstrate that the higher is the thermal expansion coefficient of the substrate, the higher is the lattice distortion of the coatings, as determined by X-ray diffraction. Following this tendency, increasing hardness values were measured in the films. By finite element simulation, the thermal stresses of the films, arising during cooling from the deposition temperature, were calculated. Good agreement was found between these stresses, the lattice distortion and the hardness of the studied W-Si-N films.