Diagnosis of GaAs solar-cell resistance via absolute electroluminescence imaging and distributed circuit modeling

A two-dimensional distributed resistance model has been used to simulate the measured dark current-voltage (J-V) curve and the absolute electroluminescence (EL) images of a GaAs solar cell, with the deviation between the simulated and experimental results smaller than 5%. The effects of different kind of defects on the EL distributions with various current densities were also analyzed, and it has been demonstrated that it was possible to identify the defects by analyzing the current-density dependent EL distributions and also by analyzing the current-density dependent voltage difference (ΔV) between the defects and normal points. •Defects were observed from the electroluminescence image of a GaAs solar cell.•Electroluminescence images of the solar cell were simulated by a circuit model.•Effects of possible defects type was analyzed by the distributed resistance model.•Defects type was identified from the current dependent electroluminescence images.•This method provides a useful technique to identify defects type in solar cells.