Correct Answer - Option 3 : electrons become the minority carriers and holes the majority carriers
CONCEPT:
- The material which is not a good conductor or a good insulator is called as the semiconductor.
- For example: Silicon, Germanium, etc.
Two types of semiconductor:
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Intrinsic semiconductors: It is an undoped semiconductor or pure semiconductor without adding any impurity
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Non-intrinsic or extrinsic semiconductor: It is a semiconductor which is doped with a specific impurity which can deeply modify its electrical properties, making it suitable for electronic applications (diodes, transistors, etc.)
- Depending upon the impurity added non-intrinsic semiconductors can be classified into P-type and N-type of semiconductors depending on weather semiconductor is rich in holes or electrons.
Explanation:
From the above explanation, we can see that,
There are two types of semiconductors:
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P-type semiconductor: The semiconductor having holes as majority charge carriers and electrons as a minority charge carrier is called as P-type semiconductor.
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When a trivalent impurity is doped in intrinsic semiconductor then we got P-type semiconductor.
- For example: gallium, indium
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N-type semiconductor: The semiconductor having electrons as majority charge carriers and holes as a minority charge carrier is called as N-type semiconductor.
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When a pentavalent impurity is doped in intrinsic semiconductor then we got N-type semiconductor.
- For example: Arsenic
Hence In an extrinsic semiconductor doped with a trivalent impurity, electrons become the minority carriers and hole the majority carriers