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).
Please see attached for solution.
The excess carrier concentration due to steady light illumination is:
dn = dp = gtn (no trapping) ...
The solution clearly explains how to obtain the quasi Fermi level given the data in the question using relevant theory.