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Question
What is meant by doping of an intrinsic semiconductor?
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Solution
The mixing of a small amount of pentavalent (e.g. phosphorus) or trivalent (e.g. aluminium) substance as an impurity in a pure semiconductor (e.g., Ge, Si) is called doping.
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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
`"n"_"i" = "n"_0 exp(- "E"_"g"/(2"k"_"BT"))`
where n0 is a constant.
Answer in detail.
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