Edge field enhanced deep depletion phenomenon in MOS structures with ultra-thin gate oxides

The edge field enhanced deep depletion phenomenon in metal-oxide-semiconductor (MOS) structure was demonstrated. The analysis in inversion to deep depletion of ultra-thin SiO
₂
and HfO
₂
was conducted using critical field model. By examine the field ratio between edge and bulk, it is observed that the HfO
₂
has larger ratio than SiO
₂
. It is supposed the edge field enhanced deep depletion phenomenon dominates both capacitance-voltage and current-voltage behavior.