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I have difficulties understanding what happens in MOS-FET-pinch-off: Take an N-MOSFET:
Near the source the gate-bulk voltage is high enough to form an inversion layer. So we have electrons as majorities in the inversion layer. As the channel potential increases towards the drain, there is less voltage difference to form an inversion layer. Ultimately, close to the drain the difference is insufficient to form an inversion-layer.
So we have a thin depleted p-layer or i-layer. I don't understand why this is still conducting.
To me this looks like an N(source), N(channel), P(pinchoff-area), N(drain) structure. I would expect that to isolate or at least require an Uf between drain and source to conduct, which is not the case.
What am I getting wrong ?
I would be interested to see a band-model-diagram from source to drain for a MOSFET in pinch-off, but I have never found any, neither in a book nor on the web.