CIGS Solar Cells for Outer Planetary Space Applications: the Effect of Proton Irradiation

The response of CIGS solar cells to 1.5 MeV proton irradiation is investigated through their photovoltaic response before and after irradiation in conjunction with proton induced defect modeling using SRIM. Simulations of the trajectory of the protons in the system indicate that the bulk of the absorber layer and the CIGS/Mo back contact are the regions most affected by proton irradiation. Additionally, SCAPS is used to qualitatively reproduce experimental current-voltage and external quantum efficiency measurements. These results allude to a systematic increase in deep defect states that result in decreased carrier extraction in the bulk and increased shunting upon irradiation.