The Effect Of The Net Carriers At The Interconnection Layer In Organic Solar Cells

The effect of net carriers at the interconnection layer in organic solar cells has been studied in our research. We use cells with structure of ITO/CuPc/C60/Alq3/Al which as the standard cell in our laboratory and single layer C60solar cell with structure of ITO/MoO3/C60/Alq3/Al as study object.There is usually an interconnection layer in the tandem organic solar cells to realize efficient recombination. Nano-metal cluster, a p-n junction, or a doped functional material have been tried as recombination layer. We used Alq3/Al/Ag/MoO3as interconnection layer in our laboratory and made a tandem device with structure of ITO/MoO3/C60/Alq3/Al/Ag/MoO3/CuPc/C60/Alq3/Al. Due to the unbalance of carrier, net carriers are piled up at the connection layer. Transfer matrix is used in this study to help the understanding of the phenomena we observed under the condition of net carrier existing.The organic solar cells with structure of ITO/MoO3/C60/CuPc/C60/Alq3/Al were made and we found that exciton dissociation, carrier recombination, exciton quenching, and carrier-exciton interaction coexist at the interconnection of tandem device by analyzing its I-V and EQE curves and comparing with performance of cell ITO/MoO3/C60/Alq3/Al/Ag/MoO3/CuPc/C60/Alq3/Al.