Recent studies have shown improved NMOSFET transistor hot-carrier lifetime
with the inclusion of a low-temperature post-metal anneal in a deuterium am
bient. There have been few published results, however, on the optimization
of the deuterium anneal or on the effect of further processing on deuterium
-annealed samples. This paper reports the first results incorporating deute
rium anneals at earlier steps in the process and the stability of the deute
rium effect with further wafer processing. We also examine the effects of v
arying deuterium concentration in the anneal from 10 to 100% and annealing
at different temperatures. Finally, the effect of combining a deuterium ann
eal with nitrided gate oxide is discussed.