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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
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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RELATED QUESTIONS
In an intrinsic semiconductor the energy gap Egis 1.2 eV. Its hole mobility is much smaller than electron mobility and independent of temperature. What is the ratio between conductivity at 600K and that at 300K? Assume that the temperature dependence of intrinsic carrier concentration niis given by
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where n0 is a constant.
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