A method for determining the p-n junction band gap from photocurrent quantum yield spectrum is proposed and substantiated in the work. The method has been applied to Ga(1-x)In(x)As p-n junctions grown by metal-organic vapor-phase epitaxy grown on metamorphic buffers. The difference between the band gap determined by the method and the electroluminescence spectrum maximum position did not exceed 3 meV. It is shown that the method can be used to determine the relationship between the band gap and the saturation current of Ga(1-x)In (a)As p-n junctions.

Electroluminescence spectra and the open circuit voltage vs photogenerated current characteristics for GaAs solar cells with different number of rows (r) of In0.4Ga0.6As quantum objects have been studied. For all samples with quantum objects, saturation current (J0), quantum object energy gap ), and the open circuit voltage drop (ΔVoc) have been obtained. A model is proposed that adequately describes the J0 – r and ΔVoс – r dependences. The model parameters have been found, including the current invariant Jz=1.4∙105 A/cm2, which uniquely connects the solar cell saturation current and a quantum object energy gap.