Match List-I with List-II
| List-I | List-II | ||
|---|---|---|---|
| Process | Result/ Characteristics | ||
| (A) | In n-type semiconductor, donor energy level | (I) | it creates holes as majority charge carriers |
| (B) | In p-type semiconductor acceptor energy level | (II) | it creates electrons as majority charge carriers |
| (C) | If semiconductor is doped with trivalent atom | (III) | is very near to valence band |
| (D) | If semiconductor is doped with a pentavalent atom | (IV) | is very near to conduction band |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → (A) - (IV), (B) - (III), (C) - (I), (D) - (II)
Doping adds energy levels inside the band gap: a pentavalent donor gives an extra electron, a trivalent acceptor leaves a vacancy (hole).
(A) In n-type semiconductor, donor energy level — this matches (IV) is very near to conduction band. The donor electron is so weakly bound that its level lies just below the conduction band.
(B) In p-type semiconductor acceptor energy level — this matches (III) is very near to valence band. A valence electron needs very little energy to fill the acceptor vacancy, so the level lies just above the valence band.
(C) If semiconductor is doped with trivalent atom — this matches (I) it creates holes as majority charge carriers. Each trivalent atom is one electron short of completing its bonds, creating a hole.
(D) If semiconductor is doped with a pentavalent atom — this matches (II) it creates electrons as majority charge carriers. The fifth electron of each dopant becomes a free electron.
NCERT (2026-27):
Extrinsic Semiconductor – “… Hence in an extrinsic semiconductor doped with pentavalent impurity, electrons become the majority carriers and holes the minority carriers.”
Extrinsic 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.”
Extrinsic Semiconductor – “… In the energy band diagram of n-type Si semiconductor, the donor energy level ED is slightly below the bottom EC of the conduction band and electrons from this level move into the conduction band with very small supply of energy. … Similarly, for p-type semiconductor, the acceptor energy level EA is slightly above the top EV of the valence band as shown in Fig. 14.9(b).”