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Question
Electric conduction in a semiconductor takes place due to
Options
electrons only
holes only
both electrons and holes
neither electrons nor holes.
Solution
both electrons and holes
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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