Non-empirical modelization of space degradation of multijunction cells

The fluence dependences of the short circuit and the open circuit voltage, induced by an irradiation, depend on a single parameter k, product of the introduction rates of the defects responsible for non radiative recombination times their trapping cross section. This parameter, characteristic of a given material, can be determined experimentally, hence allowing the computation of the degradation for any type of cell or multijunction cell. The validity of this procedure is demonstrated and illustrated in the case of the degradation of the short circuit current of 2J GaInP/GaAs/Ge cells.