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 to first-metal have been incorporated into a conventional high-performance CMOS process and subjected to subsequent processing through five levels of metal. Device hot-electron stress results confirm that, even though some initial relaxation of the transistor lifetime improvement is observed with further hot processing, significant lifetime improvement can be achieved through full wafer processing through five levels of metal. The barrier-nitride acts as a reservoir for deuterium, maintaining high concentrations in the device regions through further processing. These results support the efficacy of using a deuterium reservoir to achieve a hot-electron hardened transistor.