Electron irradiation test method for the evaluation of space solar cells

宇宙用太陽電池の電子線照射試験方法の検討

宮本 晴基; 佐藤 真一郎; 大島 武; 今泉 充*; 森岡 千晴*; 伊藤 久義; 河野 勝泰*

Miyamoto, Haruki; Sato, Shinichiro; Oshima, Takeshi; Imaizumi, Mitsuru*; Morioka, Chiharu*; Ito, Hisayoshi; Kawano, Katsuyasu*

宇宙用のInGaP/GaAs/Ge三接合太陽電池とSi太陽電池に1.0MeV, 0.8MeVの電子線を大気中にて照射(110510/cm)する際に、照射窓と試料の間の距離を20から50cmと変化させ、そのときの電気特性劣化の差異を調べた。今回の試料条件では照射される電子線のエネルギーは大気及び試料窓材(Ti)により0.93から0.71MeVまで変化するが、電子線照射による三接合太陽電池の劣化に関しては、照射窓と試料の間の距離の違いによる差異は見られなかった。Si太陽電池については0.93MeVと0.87MeVの電子線照射については変化が見られなかったが、0.73MeVまで電子のエネルギーが減衰すると劣化の減少が見いだされた。

InGaP/GaAs/Ge triple-junction (3J) and Si single junction solar cells designed for space application were irradiated with 1.0 MeV- and 0.8 MeV-electrons at 110510/cm in the atmosphere. The distance between the irradiation window and samples was changed from 20 to 50 cm. The accelerated electron energy changed from 1.0 to 0.93 MeV at the surface of samples with 20 cm below the irradiation window. This energy change caused by the energy attenuation of the Ti irradiation window and atmosphere. The electrical properties of solar cells were measured and compared before irradiation to after irradiation. No significant difference in the degradation of 3J solar cells due to electron irradiation was observed in energies range between 0.93 and 0.71 MeV. For Si solar cells, the value of degradation is the same in energies range between 0.93 and 0.87 MeV, however, the decrease in degradation was observed below 0.73 MeV.