Concept:Under reverse bias, the applied electric field acts in the same direction as the built-in electric field of the junction.
Formula:$$E_{\text{net}} = E_{\text{built-in}} + E_{\text{applied}}$$
Solution:- The positive terminal attracts free electrons in the N-region away from the junction.
- The negative terminal attracts holes in the P-region away from the junction.
- This exposes additional immobile donor and acceptor ions, widening the depletion region and creating high electrical resistance.
Why other options are incorrect:- Option A: The depletion layer expands rather than disappearing during reverse bias.
- Option B: Thinning of the depletion region is the characteristic behavior of forward bias.
- Option C: The depletion region's width and internal electric field increase proportionally with reverse bias voltage up to breakdown.
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