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Quasi Fermi Level

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Q. An n-type silicon sample with Nd=10^16cm-3 is steadily illuminated such that g'=10^21cm-s^-1. If tn0=tp0=10^-6s, calculate the position of the quasi-Fermi levels for electrons and holes with respect to the intrinsic level (assume that ni=1.5x10^10cm^-3).

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The excess carrier concentration due to steady light illumination is:

dn = dp = gtn (no trapping) ...

Solution Summary

The solution clearly explains how to obtain the quasi Fermi level given the data in the question using relevant theory.

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Separation of Quasi and Intrinsic Fermi Levels and Conductivity

An undoped Si sample is optically excited at 300K such that Gop=10^19 ehp/cm^3s and taun=taup=1 microseconds.

(a) What is the separation of the quasi Fermi levels (Efn-Efp)?
(b) Where is Efn and Efp with respect to the intrinsic Fermi level Ei?
(c) What is the change in conductivity due to excess carriers?

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