Question

When an impurity is doped into semiconductor, the conductivity of the semiconductor

• A. increases
• B. decreases
• C. remains same
• D. becomes zero

Answer 1

The correct option is A increases

The pure semiconductor has less number of thermally generated charge carriers. But when it is doped with pentavalent or trivalent impurity atoms, the number of charge carriers i.e. electrons and holes increases. So conductivity increases.