Which of the following statement(s) is/are true for p-type semiconductors?
(A) Holes are minority carriers and pentavalent atoms are the dopants.
(B) Electrons are majority carriers and trivalent atoms are the dopants.
(C) Holes are majority carriers and trivalent atoms are the dopants.
(D) Electrons are minority carriers and pentavalent atoms are the dopants.
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → (C) only
A p-type semiconductor is made by doping pure silicon or germanium with a trivalent atom such as boron or aluminium. Each dopant atom has one electron fewer than needed for the four bonds, so it creates a vacancy, which is a hole. The holes are the majority carriers and the electrons are the minority carriers.
(A) Holes are minority carriers and pentavalent atoms are the dopants. — Incorrect. The holes are the majority carriers, and the dopants are trivalent.
(B) Electrons are majority carriers and trivalent atoms are the dopants. — Incorrect. The dopants are trivalent, but the electrons are the minority carriers.
(C) Holes are majority carriers and trivalent atoms are the dopants. — Correct. This describes a p-type semiconductor.
(D) Electrons are minority carriers and pentavalent atoms are the dopants. — Incorrect. The electrons are indeed the minority carriers, but the dopants are trivalent; pentavalent dopants make an n-type semiconductor.
NCERT (2026-27):
p-type Semiconductor – “This is obtained when Si or Ge is doped with a trivalent impurity like Al, B, In, etc.”
p-type Semiconductor – “… Thus, for such a material, the holes are the majority carriers and electrons are minority carriers. Therefore, extrinsic semiconductors doped with trivalent impurity are called p-type semiconductors.”