Formation of TiSi₂ and TiN during nitrogen annealing of magnetron sputtered Ti films

Abstract

Rutherford backscattering analysis was used to evaluate TiSi2films which were prepared by sputtering Ti on various substrates and nitrogen annealing. The resulting properties were then compared with that of films prepared by thermal evaporation. Ti films were deposited on single crystal Si, polycrystalline Si, thermally grown Si02, and CVD Si3N4by dc-magnetron sputtering in an Ar plasma at a typical deposition rate of 20 A/s. Some films were passivated with a thin amorphous film of Si to compare the reaction kinetics with the samples without passivation. The temperature dependence of the electrical resistivity is basically the same as with the evaporated films [Ref. 1: C. Y. Ting et al., in Proceedings of the First International Symposium on VLSI Science and Technology (Electrochemical Society, New York, 1982), p. 224.], and the minimum value obtained after an 800 °C anneal is similar. Typical resistivity after taking into account the presence of TiN on the surface is approximately 13.9 μΩ-cm. The presence of a thin Si passivation layer (300 A) appears to prohibit the formation of TiN while allowing the formation of stoichiometric TiSi2 at a lower temperature, with a similar resistivity. © 1985, American Vacuum Society. All rights reserved.