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Statement-I: By doping silicon semiconductor with pentavalent material, the electrons density increases.
Statement-II: The n-type semiconductor has net negative charge.
In the light of the above statements, choose the most appropriate answer from the options given below:
- Statement-I is true but Statement-II is false.
- Statement-I is false but Statement-II is true.
- Both Statement-I and Statement-II are true.
- Both Statement-I and Statement-II are false.
Correct answer: Statement-I is true but Statement-II is false.
Solution
Doping silicon with pentavalent materials, like phosphorus, introduces extra electrons, increasing electron density, making Statement-I true. However, n-type semiconductors are electrically neutral overall, as the added electrons balance the positive charge of the silicon lattice, rendering Statement-II false.
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