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Question
Calculate electron & hole concentration in intrinsic Si at room temperature if
its electrical conductivity is 4x10-4 mho/m.Given that mobility of electron=
0.14m2/V-sec and mobility of holes=0.04m2/V-sec.
Solution
Data: μe=0.14m2/V-sec,μh=0.040m2/V-sec,σ=4×10-4mho/m
Formula:σi= ni(μe+μh).e
Calculations: ni=σi/e(μe+μh)
=4×10-4/1.6×10-19(0.14+0.040)
= ni=1.388×1016/m3
Answer: Carrier concentration=1.388×1016/m3
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