| 초록 |
In this work, a photomultiplication-type organic photodiode (PM-OPD) with a nanowire (NW)-embedded polymer morphology is introduced aiming prolonged carrier lifetime and enhanced carrier mobility, which contribute to more efficient gain generation. Well-defined NWs with low structural defects within P3HT : PC71BM(100:1 w/w) bulk-heterojunction (BHJ) active layer is achieved using a typical aging method. Transient photocurrent analyses show that the NW-embedded P3HT morphology suppresses electron detrapping from localized PC71BM, leading to prolonged minority carrier recombination time. Space charge limited current study shows that gradual increase in NW density in BHJ film can lead to increase of hole mobility along the vertical direction, due to increasing of efficient percolation pathways. Remarkable increase of EQE up to 250,000%, responsivity up to 1300 A W−1 and high specific detectivity up to 6.3 × 1013 Jones can be realized by embedding NW into conventional PM-OPD structure. |
