CBSE Class 12 · 2011 · SemiconductorsVery Short Answer

Explain how a depletion region is formed in a junction diode.

Solution

As a p-n junction is formed, holes diffuse from the p-side to the n-side and electrons diffuse from the n-side to the p-side.
Near the junction these carriers recombine, leaving behind immobile negative acceptor ions on the p-side and positive donor ions on the n-side.
This narrow region, devoid of mobile charge carriers, is the depletion region.

Diffusion and recombination of majority carriers leave immobile ions: the depletion region.

CBSE Class 12 Board · 2011 · Subjective

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