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Question
When an impurity is doped into an intrinsic semiconductor, the conductivity of the semiconductor
Options
increases
decreases
remains the same
become zero.
Solution
increases
When an impurity (either a p-type atom or an n-type atom) is doped into an intrinsic semiconductor, it increases the number of charge carriers in the intrinsic semiconductor. As conductivity is directly related to the number of charge carriers, the conductivity of a semiconductor increases with doping.
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