Question
Electric conduction in a semiconductor takes place due to:
- Electrons only.
- Holes only.
- Both electrons and holes.
- Neither electrons nor holes.
✓
Answer
- Both electrons and holes.
Explanation:
A hole is created in a semiconductor when a valence electron moves to the conduction band. When potential difference is applied across the semiconductor, the electron drifts opposite to the electric field applied, while the hole moves along the electric field. Therefore, electric conduction takes place in a semiconductor because of both electrons and holes.
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