Improved hot-electron reliability in high-performance, multilevel-metal CMOS using deuterated barrier-nitride processing

Deuterated barrier-nitride films and anneals in a deuterium ambient prior t o first-metal have been incorporated into a conventional high-performance C MOS process and subjected to subsequent processing through five levels of m etal. Device hot-electron stress results confirm that, even though some ini tial relaxation of the transistor lifetime improvement is observed with fur ther hot processing, significant lifetime improvement can be achieved throu gh full wafer processing through five levels of metal. The barrier-nitride acts as a reservoir for deuterium, maintaining high concentrations in the d evice regions through further processing. These results support the efficac y of using a deuterium reservoir to achieve a hot-electron-hardened transis tor.