STUDY AND IMPROVEMENT OF THE ADHESION OF CHROMIUM THIN-FILMS DEPOSITED BY MAGNETRON SPUTTERING

Pure and doped chromium coatings are deposited on glass substrates by magnetron sputtering. By varying the reactive gas content, tensile intrinsic stress transitions to compressive ones are observed. Scratch tests have demonstrated a good adhesion for doped chromium coatings which are in a compressive state. Doped nitrogen chromium films have the highest values of the critical load at which adhesion fails (17 N). Pure chromium coatings are in tensile stresses and the critical value is only 11 N. Adhesion and intrinsic stress dependences are shown. These results are correlated with average crystallographic grain size, preferential crystalline orientation, morphology and microhardness.