IS TI CONTAMINATION IN SI WAFER PROCESSING AN ISSUE

Although TiN and TiSi2 films are widely used in silicon wafer fabs, th e possibility of titanium contamination adversely affecting device cha racteristics remains a great concern. In this study, ion implantation was used to determine the critical level of titanium which significant ly reduces carrier lifetime in a silicon substrate. Possible contamina tion Vectors (wet etch solutions and hot processes), the diffusion of titanium in silicon, and the effect of oxidation and cleaning of subst rates intentionally contaminated with Ti have been investigated. With reasonable safeguards, titanium contamination is not a critical proble m.