CBSE Class 12 · 2020 · SemiconductorsVery Short Answer

How does an increase in doping concentration affect the width of depletion layer of a p-n junction diode?

Answer: An increase in doping concentration decreases (reduces) the width of the depletion layer.

Solution

The depletion width adjusts so that the exposed ionic charge on the two sides balances.
Heavier doping packs more ionised impurity atoms per unit volume, so the required charge is exposed over a shorter distance.

Higher doping \Rightarrow narrower depletion layer.

CBSE Class 12 Board · 2020 · Subjective

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