Formation of high temperature phases in sputter deposited Ti-based films below 100 degrees C

This article reports on the sputtering of pure Ti and Ti-based alloy films onto substrates where the temperature T-s was kept below 100 degrees C, using the magnetron sputter ion plating process. It was found that while the pure Ti film is a hexagonal low-temperature phase film (h-alpha Ti), the Ti-Cr, and Ti-Fe alloy films, containing a relatively small amount of Cr or Fe of about 10 wt %, are cubic high-temperature beta phase Ti alloy films [c-beta Ti(Cr) or c-beta Ti(Fe)]. This finding is of immense importance both scientifically and practically. The conditions under which high-temperature phases are formed in alloy films sputtered at substrate temperatures below 100 degrees C, which is much lower than the temperature necessary to form these high-temperature phases (T-htp) according to the equilibrium phase diagram, will be discussed in detail. X-ray diffraction analyses of these films will also be presented. (C) 1996 American Vacuum Society.