Radiation degradation modeling of triple-junction space solar cells

Sato, Shinichiro; Imaizumi, Mitsuru*; Oshima, Takeshi

Degradation modeling of triple junction (3J) solar cell due to proton and electron irradiation is performed with the use of a one dimensional optical device simulator. By fitting external quantum efficiencies of the 3J solar cells degraded by proton or electron irradiation, the short circuit current (Isc) and open circuit voltage (Voc) are simulated. These simulated values are in good accordance with the experimental data. In this modeling, carrier removal rate of base layer () and the damage coefficient of minority carrier diffusion length () in each sub cell are considered as radiation degradation parameters. NIEL (Non Ionizing Energy Loss) analysis for both radiation degradation parameters is discussed. The radiation degradation of a 3J solar cell can be predicted from correlativity between NIEL and radiation degradation parameters.