The internal quantum efficeincy is the ration of the internally generated photon flux F in photons/cm^2/s to the current density per J unit charge q, That is
I qe= q F/ J wheee q is the electronic charge.
So one has to pass current J in the diode and calculates F using the device solver Sivaco.
The external quantum efficiency Eqe= Iqe x the optical path efficiency