Concept:During the formation of a \(\text{p-n}\) junction, electrons and holes diffuse across the boundary and recombine, leaving behind uncompensated, fixed positive donor ions on the n-side and fixed negative acceptor ions on the p-side. This space-charge layer is depleted of all mobile charge carriers.
Formula:Qualitative concept / No formula required.
Solution:- Diffusion of majority carriers leads to mutual neutralization at the interface.
- The remaining uncovered charges are fixed lattice ions that form the depletion region.
- Consequently, this region lacks free electrons and mobile holes.
Why other options are incorrect:- Option B: The neutral p-region contains abundant free mobile holes as majority carriers.
- Option C: The neutral n-region contains a high concentration of mobile conduction electrons.
- Option D: Metallic contacts contain a high density of free conduction electrons.
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