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The VRTDDB(Voltage-Ramping Time-Dependent-Dielectric-
Breakdown),a reliability testing method for the gate
dielectrics ,is proposed in this thesis. We used different
bulks and dielec- tric materials,oxide thickness,peripheral
conditions to evaluate the reproducibility of this testing
method while it is applied in IC mass production. Provided that
the oxide breakdown obeys the log-normal dis- tribution,the
"electric field acceleration factor" is calculated. According
to this parameter, this testing method is proved to be useful
and faster than constant-field TDDB testing method. Using this
proposed testing method, we can get high reproducibility for
all kinds of gate dielectrics. We can also conclude that ONO,
thinner SiO2 and SiO2 on N-Well have stable reliability.
Finally, we compare the data measured by VRTDDB with that by
TDDB, it is found that they are compatible. So, VRTDDB can be
use as a testing method for gate dielectrics.
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