Question
Distinguish between intrinsic and extrinsic semiconductors?
Solution
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Intrinsic semiconductor |
Extrinsic semiconductor |
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1. It is a pure semiconductor material with no impurity atoms in it. |
1. The pure semiconductors doped with tetravalent or pentavalent impurity atoms are called extrinsic semiconductors. |
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2. Their electrical conductivity is low. |
2. Their electrical conductivity is high. |
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3. Number of free electrons in the conduction band is equal to the number of holes in the valence band. |
3. Number of holes is never equal to the number of electrons. No. of electrons is greater in n-type semiconductor and number of holes is greater in p-type semiconductor. |
