Effect of Ti interlayer and bias on structure and properties of TiN films

The paper reports on properties and structure of the TiN films, which have been deposited on titanium interlayer covering a steel substrate. The Ti in terlayer and the TiN film were prepared by d.c. magnetron sputtering in Ar and Ar + N-2 mixture, respectively. Three Ti interlayers with different thi ckness h(Ti) = 0.01, 0.1 and 0.2 mu m were prepared under the sane conditio ns and investigated. It was found that the macroscopic residual stress in t he TiN films is compressive and increases with the increasing negative bias up to approximately -150V. Also the size of the TiN crystallites decreases with the increasing negative substrate bias, varying between 250 nm and 11 nm. The critical load, which characterises the film adhesion, increases wi th increasing h(Ti). For h(Ti) greater than or equal to 0.1 mu m, the criti cal load almost does not depend on the bias voltage.