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Question
Let np and ne be the numbers of holes and conduction electrons in an extrinsic semiconductor.
Options
np > ne
np = ne
np < ne
np ≠ ne
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Solution
np ≠ ne
Extrinsic semiconductors are formed by doping either an n-type material or a p-type material with a pure semiconductor, Thus, it may have more number of holes (if the doping material is of p type) or more number of electrons (if the doping material is of ntype).
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