Characterization of the Defects Introduced by Proton and Electron Irradiation in GaAs Solar Cells via Dark I-V Analysis
Carmine Pellegrino1,2, Alessio Gagliardi2, Claus G. Zimmermann1
1Airbus Defence and Space GmbH, Taufkirchen, Germany
/2Technical University of Munich, Institute for Nanoelectronics, Munich, Germany

An analytical model based on Shockley‑Read‑Hall statistic is used to reproduce the dark J-V characteristics of proton and electron irradiated GaAs isotype cells. The model aims to describe the recombination phenomena in the junction depletion region by a discrete distribution of defect levels in the bandgap, located away from the intrinsic Fermi level position. This facilitates a detailed understanding of the different effectiveness of a given displacement damage dose introduced through protons or electrons in terms of open-circuit voltage degradation. Defect lifetimes and introduction rates are extracted solely by analyzing the dark J‑V characteristics of irradiated cells.