For n-type semiconductor, which of the following statements is true?

The correct answer is Option (4) → Pentavalent atoms are the dopant and holes are the minority carriers.

An n-type semiconductor is made by doping silicon or germanium with a pentavalent atom (As, P, Sb). Four of its five valence electrons form bonds and the fifth is free, so electrons are the majority carriers, while the few thermally generated holes are the minority carriers.

Option (1) Trivalent atoms are the dopant and electrons are majority carriers. — Incorrect. A trivalent dopant makes a p-type semiconductor.

Option (2) Trivalent atoms are the dopant and holes are majority carriers. — Incorrect. Trivalent dopants give holes as majority carriers, which is the p-type case, not the n-type.

Option (3) Pentavalent atoms are the dopant and electrons are minority carriers. — Incorrect. The dopant is right, but electrons are the majority carriers, not the minority ones.

Option (4) Pentavalent atoms are the dopant and holes are the minority carriers. — Correct. Pentavalent dopant; electrons are the majority carriers and holes the minority carriers.

NCERT (2026-27):
Extrinsic Semiconductor – “… Thus, with proper level of doping the number of conduction electrons can be made much larger than the number of holes. Hence in an extrinsic semiconductor doped with pentavalent impurity, electrons become the majority carriers and holes the minority carriers. These semiconductors are, therefore, known as n-type semiconductors. For n-type semiconductors, we have,

    \( \displaystyle n_e \gg n_h \qquad (14.3) \) ”