MOS C-V measurment 1

[tz0003]

Hi, all
when I do MOS C-V measurment, when the oxide is really leaking, or R is samll. no matter Cs or Cp mode, the C-V curve wouldn't satuate. so what is the wrong? is it the MOS behaves differently at this situation or the isntrument used is getting false readings?

regards,
tao

 

[IRstuff]

Don't you think that it's essentially both?

CV curve saturation implies that there is an inversion layer that provides conductance to the bottom of the oxide capacitance. If there's leakage, then current is being pumped into the inversion layer that shouldn't be there, potentially changing the apparent delta-V across the oxide itself as well as potentially affecting the IR drop in the inversion layer.

As a side note, what't the point of measuring CV on a leaky oxide? It's essentially useless for device operation, isn't it?

TTFN