how to measure threshold voltage of SOI MOS capacitor

[sangithars]

please tell me the accurate method to measure the threshold voltage of a silicon on insulator(SOI) MOS capacitor. One method i know is from the CV measurement .But that is not very accurate.Please help...Its very urgent.

Thanks in advance.

 

[keith1200rs]

I would just charge it with a current and then plot i/(dV/dt) against V. I did that with an SOI cap (poly over nWell) and got the attached.

You could do an AC analysis and step the DC vale but that won't give a direct plot of capacitance.

Keith.