Junction diode - unequally doped sides

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    Diode Junction
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Discussion Overview

The discussion revolves around the behavior of the depletion layer in a p-n junction diode, particularly focusing on the scenario where one side is lightly doped and the other is heavily doped. Participants explore the mechanisms involved when the diode is reverse-biased and seek to understand the movement of charge carriers in this context.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • One participant questions why the depletion layer penetrates the lightly doped p-side of a p-n junction diode when the n-side is heavily doped, expressing confusion about the underlying mechanism.
  • Another participant notes that the sum of electrons and holes remains constant, suggesting that the density of holes affects the volume with holes, but does not directly address the original question.
  • A third participant expresses confusion about the question itself, stating that depletion occurs on both sides as electrons move into holes unless the diode is in a conducting mode.

Areas of Agreement / Disagreement

Participants do not appear to reach a consensus on the original question regarding the penetration of the depletion layer, and there are multiple interpretations of the mechanisms involved.

Contextual Notes

There are unresolved assumptions regarding the behavior of charge carriers in reverse bias and the specific definitions of depletion layer characteristics in relation to doping levels.

hitcool007
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Why does the depletion layer penetrate a lightly doped side of a p-n junction diode?? Consider that there is a lightly doped p-side and a heavily doped n-side in a p-n junction diode , which is connected to a dc power supply in reversed biased. Now, I've read that depletion layer penetrates the p-side in this case. But i could not figure out the reason behind it. So, Can u please explain me the mechanism involved in terms of the movement of electrons in the circuit.
Im in a faulty assumption that the side in which the diode is more heavily doped is bound to be penetrated more by the depletion layer..
(-I've completed my intermediate)
 
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The sum of electrons and holes stays constant (the whole thing does not get a significant net charge). If the hole density is larger, the volume with holes is smaller, and vice versa.
 
ok,, but i dint get the answer to my question!
 
In this case, I don't understand the question. You have depletion at both sides as electrons from one side move into the holes at the other side, unless your diode is in a conducting mode.
 

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