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Consider a n-type semiconductor in which n_e and n_h are number of electrons and holes, respectively. (A) Holes are minority carriers (B) The dopant is a pentavalent atom (C) n_e n_h = n_i^2 (where n_i is number of electrons or holes in semiconductor when it is intrinsic form) (D) n_e n_h ≥ n_i^2 (E) The holes are not generated due to the donors Choose the correct Ans. from the options given below: (1) (A), (B), (C) only (2) (A), (B), (E) only (3) (A), (C), (E) only (4) (A), (C), (D) only

1. (A), (B), (C) only
2. (A), (B), (E) only
3. (A), (C), (E) only
4. (A), (C), (D) only

Correct answer: (A), (C), (D) only

Solution

In an n-type semiconductor, holes are indeed minority carriers (A), the product of electron and hole concentrations equals the square of the intrinsic carrier concentration (C), and the relationship n_e n_h ≥ n_i^2 holds true due to the presence of excess electrons from donor atoms (D).

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