In a p-n junction diode, the depletion region is created primarily due to: MCQ with Answer and Explanation

In a p-n junction diode, the depletion region is created primarily due to:
A. Drift of electrons under a strong electric field.
B. Diffusion of majority charge carriers across the junction.
C. Recombination of minority carriers.
D. Heating of the semiconductor material.
Answer: Option B
Solution (By JKSSB Mock Tests)
When a p-type and an n-type semiconductor are joined, electrons from the n-side (majority carriers) diffuse across the junction to the p-side, and holes from the p-side diffuse to the n-side due to concentration gradients. They recombine near the junction, leaving behind immobile ionized atoms (positive donor ions on n-side, negative acceptor ions on p-side). This uncovered charge region is the depletion layer.

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