Concept:Reverse bias lowers the electrostatic potential of the P-region relative to the N-region, increasing the potential energy barrier for majority carriers.
Formula:$$q V_{\text{net}} = e(V_B + V_R)$$
Solution:- Reverse bias lowers the electron energy levels of the P-side relative to the N-side.
- This increases the total energy barrier across the junction to \( e(V_B + V_R) \).
- The higher barrier further suppresses majority carrier diffusion across the junction.
Why other options are incorrect:- Option A: The barrier increases rather than decreasing to zero.
- Option B: Biasing changes band alignment across the junction; it does not convert valence bands into conduction bands.
- Option C: The increased barrier height blocks majority carrier diffusion.
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