Question
What is an intrinsic semiconductor? How can this material be converted into (1) P-type (2) N-type extrinsic semiconductor? Explain with the help of energy band diagrams.

Answer

Intrinsic semiconductor: Pure semi-conductor having no impurities or negligible impurities.Conversion into –
  1. P-type – by doping with small amount of trivalent impurities.
  2. N-type- by doping with small amount of pentavalent impurity.

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