Life Tests and
TDDB Life Prediction Modeling of 50 nm Silicon Nitride Capacitors
TriQuint Semiconductor,
500 W Renner Road, Richardson, TX 75080, Email: gdrandova@tqtx.com, Phone:
(972) 994-5766
Keywords: Silicon nitride,
capacitor life time, TDDB, linear field model, Frenkel-Poole.
Abstract
In this paper we report
room temperature constant voltage life-time measurements of silicon nitride
capacitors with 50 nm dielectric thickness for both voltage polarities. We show
that the measured life times are longer than predicted by both the linear field
model and a model based on dielectric conduction due to Frenkel-Poole emission
from traps. Of the two models, the latter fits better the collected data. We
point out areas for its improvement and provide additional measurements of
leakage as a function of time and a calculation of total charge to failure. Life-time
measurements at elevated temperatures were performed and showed an expected
exponential behavior.