CHARACTERIZATION OF THE OPTICAL-PROPERTIES AND COMPOSITION OF TINX THIN-FILMS BY SPECTROSCOPIC ELLIPSOMETRY AND X-RAY PHOTOELECTRON-SPECTROSCOPY

Thin films of TiNx with 0.34 < x < 1.19 were deposited on silicon subs trates by a filtered are deposition process, Spectroscopic ellipsometr y (SE) in the energy region 1.5-3.5 eV was used to measure the optical properties of the films, X-ray photoelectron spectroscopy (XPS) was u sed to determine the relative atomic concentration and the chemical st ates of the elements, The dielectric function epsilon(omega) measured by ellipsometry gives the optical response of TiNx films and valuable information on their chemical composition, which is also verified by X PS. The plasma energy omega(p) of TiNx films was found to depend stron gly on the N/Ti ratio and this is correlated with the value of x as de termined by XPS and Rutherford backscattering spectroscopy (RES), The results show that, via the calibration, spectroscopic ellipsometry may be used to estimate the stoichiometry of deposited TiNx films.