Sputter deposited TiN films are commonly used as diffusion barriers for an aluminum based metallization and as glue layers for tungsten films in ULSI device processing. TiN is also used in conjunction with Ti and/or a-Si for local interconnect and salicide processing. For the above applications, TiN films are also subjected to rapid thermal processing.
This paper discusses these applications focusing on sub-half micron technologies where high aspect ratio contacts causes poor step coverage at the base of the contacts and compact design rule requirements pose an additional burden to Ti-silicide processes. Preferred grain orientation, microroughness, film stress, sheet resistance, diffusion barrier qualities and analytical spectroscopy techniques have been used to characterize the material modifications by RTP of Ti and Ti/TiN thin films.