A study on the variation of c-Si solar cell parameters under 8 MeV electron irradiation

This paper reports on the photon and 8 MeV electron irradiation effects on electrical parameters, quantum efficiency and minority carrier lifetime of a c-Si solar cell. The effect of subsequent photon irradiation on the silicon solar cells, degraded by 8 MeV electron irradiation is also investigated. The current-voltage (I-V) characteristics of solar cells under AMO illumination condition were studied before and after the irradiation. The solar cell parameters such as short circuit current (I sub(sc)), open circuit voltage (V sub(oc)), fill factor (FF), and conversion efficiency ([eta]) were found to decrease after electron irradiation. A slight improvement in the electric performance of solar cells is observed after the photon irradiation. The spectral response shows that the quantum efficiency for low energy photons is reduced, suggesting that the damage is mainly inflicted to the bulk of the absorber material. This is strongly supported by the minority carrier lifetime results, which show a clear trend of decreasing carrier lifetime and carrier diffusion length as radiation dose increases.