Control of morphology (ZrN crystallite size and SiN x layer thickness) in Zr–Si–N nanocomposite thin films

DC reactive magnetron sputtering was used for the deposition of Zr–Si–N thin films. Four series of samples have been deposited at various substrate temperatures T S: 300 K, 510 K, 710 K and 910 K. Depending on T S, different N 2 partial pressures p N2 were required to obtain nearly stoichiometric ZrN films. Si content ( C Si) was varied in each series by changing the power applied on the Si target, whereas the power on the Zr target was kept constant. The microstructure of the coatings was examined by XRD and in cross-section by transmission electron microscopy (TEM). Depending on T S and p N2, the deposition rate showed significant variations from 0.04 to 0.18 nm/s. The correlation between film morphology (preferential orientation of crystallites, grain size, column dimensions, thickness of the SiN x layer covering ZrN crystallites) and the deposition conditions (power applied on Si target, temperature, nitrogen partial pressure and deposition rate) provides useful information for optimizing the deposition process.