Concept:In reverse biasing, the positive terminal of the external source connects to the n-type region and the negative terminal to the p-type region. This pulls majority electrons in the n-region and majority holes in the p-region away from the junction interface.
Formula:$$V_{\text{net}} = V_0 + V_r$$
Solution:- The external field aligns in the same direction as the internal built-in electric field.
- Majority carriers are drawn away from the junction, exposing additional immobile ionized donor and acceptor atoms.
- This broadens the space-charge layer and widens the depletion width \(W\).
Why other options are incorrect:- Option B: Pushing majority carriers across the junction occurs exclusively in forward bias.
- Option C: Thermal generation depends on temperature, not on the applied bias polarity.
- Option D: Immobile ions are uncovered, not neutralized, thereby increasing the depletion region width.
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