PHOTOLUMINESCENCE STUDY OF SILICON SOLAR-CELLS IRRADIATED WITH LARGE FLUENCE ELECTRONS OR PROTONS

In order to investigate the anomalous degradation of space silicon sol ar cells which was found in large fluence region, photoluminescence me asurements are carried out for the cells irradiated with 1 MeV electro ns with a fluence exceeding 1 x 10(16) e/cm(2) and 10 MeV protons with a fluence exceeding 1 x 10(13) p/cm(2). For both irradiation, the int ensity of boron-related bound exiton line decreases with fluence and i t disappears at the fluences where the anomalous degradation occurs. T he dominant defect is a complex of an interstitial carbon and an inter stitial oxygen (CI-OI). The generation of five-vacancy-defects was als o observed for the proton irradiation. Variations of photoluminescence line intensity are discussed in terms of displacement damage dose cal culated based on nonionizing energy loss (NIEL). (C) 1998 Elsevier Sci ence Ltd. All rights reserved.