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Question
Two crystals C1 and C2, made of pure silicon, are doped with arsenic and aluminium respectively.
Identify the extrinsic semiconductors so formed.
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Solution
Arsenic is pentavalent. So, C1 doped with arsenic will form an n-type semiconductor.
Aluminium is trivalent. So, C2 doped with aluminium will form a p-type semiconductor.
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