Device parameter degradation of p-MOSFETs after Negative Bias Temperature S
tress (NBTS) and the related charge trapping mechanisms are investigated in
detail. Applying specific annealing experiments to NBT-stressed transistor
s, the influence of stress-induced oxide charge build-up and interface stat
e generation on the degradation of the electrical parameters is evaluated.
It is found, that hole trapping significantly contributes to the NETS-induc
ed V-t shift. Furthermore, experimental results of the hot-carrier behavior
of virgin and NET-stressed devices demonstrate that only weak correlations
between these types of stress and the involved degradation mechanisms exis
t, which is important in applications with alternating stress situations. (
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