On the post-contamination effect on the delamination of sputtered amorphous carbon nitride films

The analysis of post-contamination effect on delamination of amorphous carbon nitride (a-CNx) films deposited by RF magnetron sputtering of a graphite target in pure nitrogen plasma. Combined atomic force microscopy (AFM) and Fourier Transform Infrared (FTIR) measurements are used to fully characterise the films. Various shapes of debonding patterns, such as straight-sided blisters or worm-like structures, have been observed. The microstructure analysis revealed the porous character of the films and their post-deposition contamination by oxygen and water. The observed delamination of the films results from high residual compressive stresses created during diffusion and chemical reaction of water at the film/substrate interface through the porosities, possibly accompanied by volume expansion which support delamination crack advance.