Why are the Quasi-Fermi levels in Schottky/Ohmic contacts always zero


#1

I am trying to simulate semiconductor-metal junctions (c.f. attached file). a general question is why the quasi-Fermi levels (Efn and Efp) are always equal to zero? I simulated other similar junctions with other materials and always Efn adn Efp are equal to zero everywhere.

test.ldev (5.9 MB)


#2

The CHARGE solver uses the Fermi level of an electrical contact (randomly selected) as the reference potential. The potential of that Fermi level is thus set to zero and the potential all other energy bands are expressed with respect to that. This is why the quasi Fermi levels are always set to zero at equilibrium. As you apply a voltage to the system and it moves away from equilibrium, you will see that the quasi Fermi levels are no longer zero everywhere.


#3

That makes sense. Thanks very much!