Adhesion analysis of silicon nitride film deposited on stainless steel surface by adding transition layer.

Adhesion is a major factor in film failure. Based on the basic theory of interfacial toughness, the relationship between film thickness and internal stress and adhesion is qualitatively analyzed. The adhesive properties of silicon nitride deposited on stainless steel substrate by plasma enhanced chemical vapor deposition methods (PECVD) is discussed. The case where nickel, nickel-chromium and alumina films are respectively used as transition layers is compared. After vacuum annealing thermal treatment of these films, the results show that the alumina film has better matching performance with 304 stainless steel, and the interface toughness is improved by 51.2% compared with the silicon nitride film. After the samples are stretched, the silicon nitride film show a large number of cracks when the transition layer is nickel or nickel-chromium, possibly due to the large thermal stress in the film. At the same time, the process parameters of magnetron sputtered alumina are optimized, and the optimal deposition rate of alumina film is determined to be 40.25 nm/min. Then, the effect of film thickness on adhesion is investigated by theoretical analysis and tape breakage test. As the film thickness ratio of alumina and silicon nitride increases, the adhesion is optimal.