FT-IR study of electron- or proton-irradiated Si crystals for solar cells

Low-temperature infrared (IR) absorption measurements under above-gap illum ination were done to investigate the degradation behaviors of Si crystal fo r solar cells. The concentration of boron acting as an acceptor decreased w ith increasing radiation doses of 1 MeV electrons or 10 MeV protons. A new band around 520 cm(-1) was observed in irradiated samples. These results in dicate that the boron configuration was changed at Si site by the irradiati on. Annealing experiments showed that the concentration of boron accepters restored by annealing around 300 degrees C. (C) 2000 Elsevier Science B.V. All rights reserved.