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If in the saturation region the inversion layer is pinched off then how do electrons flow from source to drain?
Doesn't pinch off of inversion layer mean the loss of channel in the MOSFET for current flow?

Harshit Rajgadia
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Why MOSFET Pinchoff occurs
This answer will help you! You are right about the channel getting pinched, so how will electrons flow!? However, also keep in mind that there is electric field setup too! And force due to this field, pushes the electrons to the drain.
Read the answer posted by Vasiliy, it will clear you doubts!

Pranit Pawar
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Being in saturation does not mean a mosfet is not conducting current. It means the drain current no longer increases with increases of Vd.

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Don't confuse pinch off with turning the device off which you would do my making Vgs zero.

owg60
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  • thanks for your answer but if the inversion layer is pinched off how does current flow through the pinched off region?In first case Vgs is zero due to which the there remains no channel for current to flow and in the second case the channel does not completely connect drain and source because of pinch off.Don't the two cases look same. – Harshit Rajgadia Nov 09 '16 at 14:03
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At saturation mode N-MOS turns to current source mode (infinite source-drain resistance). It is still possible small changes in source-drain current due to channel length modulation.

Vth and pinch-off region

Dr. Che
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  • What his question means is that if the inversion layer is pinched off, it doesn't reach the drain. So how will electrons flow if the channel itself is pinched or "broken" – Pranit Pawar May 25 '19 at 16:11