Concept:Doping introduces donor or acceptor states that create a large majority carrier population. Thermally generated carriers of the opposite polarity make up the minority carrier population.
Formula:$$\text{N-type: } n_n \gg p_n \implies p_n = \frac{n_i^2}{N_D} \text{ (Minority: Holes)}$$
$$\text{P-type: } p_p \gg n_p \implies n_p = \frac{n_i^2}{N_A} \text{ (Minority: Electrons)}$$
Solution:- In N-type material, pentavalent dopants make electrons the majority carriers, leaving thermally generated holes as the minority carriers.
- In P-type material, trivalent dopants make holes the majority carriers, leaving thermally generated electrons as the minority carriers.
Why other options are incorrect:- Option B: This lists the majority carriers for each material.
- Option C: Fixed donor and acceptor ions are immobile lattice sites, not mobile carriers.
- Option D: Protons and neutrons are bound in atomic nuclei.
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