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Question
Which of the following statements are true about semiconductors?
(i) Silicon doped with electron-rich impurity is a p-type semiconductor.
(ii) Silicon doped with an electron-rich impurity is an n-type semiconductor.
(iii) Delocalised electrons increase the conductivity of doped silicon.
(iv) An electron vacancy increases the conductivity of n-type semiconductor.
Solution
(ii) Silicon doped with an electron rich impurity is an n-type semiconductor.
(iii) Delocalised electrons increase the conductivity of doped silicon.
Explanation:
Silicon (valence electron – 4) doped with electron rich impurity is an n-type semiconductor due to extra electron and the delocalised electrons increase the conductivity of doped silicon.
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