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Owing to the necessity in scaling of MOS products for the past
few years, MOS device dimensions have been shrinked to below
one micron with oxide thickness reduced such as to cause a high
electric field in the gate-to-drain overlap region. This
increased electric field can cause seriously the band-to-band
tunneling phenomenon in off-state thin oxide MOSFET's. The gate
-induced drain leakage current (GIDL) is therefore generated,
and will dominate the drain leakage current at off-state
condition. For the submicron buried-type p-channel LDD MOSFET'
s, a new observation of the anomalous drain leakage current-
voltage characteristics measured in a gated-diode configuration
have been reported. This thesis first presents a new physical
model taking into account the electrons accumulated in the gate-
to-drain overlap region, which can eliminate the uncertainties
in determining the parameter values when applying the deep
depletion approximation theory. The measured anomalous drain
leakage current-voltage characteristics have been reasonably
reproduced based on this new model.
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