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Question
Distinguish between 'intrinsic' and 'extrinsic' semiconductors
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Solution
| Intrinsic Semiconductor | Extrinsic Semiconductor |
| It is a pure semiconductor material with no impurity atoms in it. | It is prepared by doping a small quantity of impurity atoms to the pure semiconductor. |
| The number of free electrons in the conduction band and the number of holes in valence band is exactly equal. | The number of free electrons and holes is never equal. There is an excess of electrons in n-type semiconductors and an excess of holes in p-type semiconductors. |
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