In this paper, we present a non-contact C-V technique
for ultra-thin dielectrics on silicon. The technique
uses incremental corona charging of dielectric and a
measurement of the surface potential with a vibrating
capacitive electrode. A differential quasistatic C-V
curve is generated using time-resolved measurements.
The technique incorporates transconductance corrections
that enable corresponding ultra-low electrical oxide
thickness (EOT) determination down to the sub-nanometer
range. It also provides a means for monitoring the flat
band voltage, VFB, the interface trap spectrum,
DIT, and the total dielectric charge, QTOT. This
technique is seen as a replacement for not only MOS C-V
measurements but also for mercury-probe C-V. In addition, EOT
measurement by the corona C-V has a major advantage over optical
thickness methods because it is not affected by water adsorption
and molecular airborne contamination, MAC. These effects have
been a problem for optical metrology of ultra-thin dielectrics.