| 초록 |
A novel organic conjugated polymer, poly(((2,5-difluoro-1,4-phenylene)bis(thiophene- 5,2-diyl))-alt-(5,6-bis(tetradecyloxy)benzo[c][1,2,5]thiadiazole-4,7-diyl))(PDTFBT), was designed and utilized for use in organic photodiodes (OPDs) as a donor material. The fluorinated weak donor (WD)-alkoxy substituted weak acceptor (WA) structure of the PDTFBT was formed a specific absorbance in the adjacent green light. As a result, S-F and S-O dipole-dipole interactions of PDTFBT retained the constant responsivity and significantly improved the detectivity of PDTFBT:PC71BM devices even with a the thick active layer of 470 nm. The OPDs of PDTFBT:PC71BM system showed a specific detectivity (D*) of 1.27×1012 Jones, low dark current of 1.22×10-7 A/cm2 and high photo-responsivity of 0.25 A/W at the wavelengths from 560 nm under -1 V. We believe that our synthetic strategy to build the wide bandgap polymers provides a general guidance for developing OPDs for X-ray detector. |
