Hi All

I want to model the MOS gate cap variation with VGS voltage in transient domain. Means lets say when the VGS changes abruptly bringing the MOS from OFF state to ON state ( subthreshold or full inversion) I see in simulations the gate cap is changing instantly which I doubt wont be the case. At least while going from OFF to subthreshold I expect there should be some time constant involved between VGS variation and the gate cap change as the channel inversion charge comes mostly from its bulk which are minority carriers.

1) Is my understanding correct?    
2) How can I model this effect ?
3) Is there a way to check this behavior on silicon for a MOS?

Thanks in advance for any feedback/suggestions on this topic