多晶硅电池中反向击穿机制的研究

Electroluminescence (EL) imaging was utilized to investigate spatial distribution of electric properties of solar cells based on multicrystals Si. Under variable reverse bias, different types and positions of light-emitting are observed, and measure J-V-T. By analyzing the reverse I-V-T function, it is found that the light-emitting between -8 V and -12 V is due to electrons tunneling from P-zone to N-zone and electronhole recombination; and from positive J-V-T curve, it is evidence that the tunneling is most interface defects induced, which can explain that the reason of different brightness of EL on variable bias. For further verify our conclusion, we investigated the different brightness position by Surface photovoltage（SPV） method. Through the change of the bandgap and surface potential difference, we find results are accordance with that of J-V-T curve.