CBSE Class 12 · 2023 · SemiconductorsMultiple Choice

The formation of depletion region in a p-n junction diode is due to

(A)Movement of dopant atoms
(B)Diffusion of both electrons and holes✓ Correct
(C)Drift of electrons only
(D)Drift of holes only

Answer: (B)

Solution

When the junction forms, electrons diffuse from the n-side to the p-side and holes diffuse from the p-side to the n-side.
Their recombination near the junction leaves immobile ions and creates the carrier-free depletion region.

(B) Diffusion of both electrons and holes.

CBSE Class 12 Board · 2023 · Single correct option

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