Comments on Bias of PN Junctions


(for realistic devices, the built-in field is always larger than the applied field)? is that true? I confused to understand

Yes, for a solar cell producing power the electric field at the junction in V/cm is greater than the applied field. Its possible to add a very large external voltage so that the applied field in a diode is larger than the built-in field. At that point the diode is more like a resistor.