摘要
Abstract In this study, a kind of fluorinated copolyfluorene, named poly[（4-（octyloxy）-9,9-diphenylfluorene-2,7-diyl）-alt- （2,3,5,6-tetrafluoro-1,4-phenylene）] （PODPF-TFP）, is synthesized by facile palladium-based direct aromatization. Compared to the non-fluorinated counterpart, poly[（4-（octyloxy）-9,9-diphenylfluorene-2,7-diyl）-alt-（p-phenylene）] （PODPF-P）, deeper HOMO/LUMO energy level combined with steric hindrance effect endow PODPF-TFP with excellent spectra and morphology stability. Finally, organic field-effect transistor （OFET） memory devices are fabricated with PODPF-P/PODPF- TFP as the dielectric layers, and they both exhibit flash type storage characteristic. Owing to the electronegativity of fluorine atom, the device based on PODPF-TFP exhibits larger memory window and more stable Ion/Ioff ratio during a retention time of 10^4 s as well as a better aging stability. The present study suggests that fluorinated p-n copolyfluorene electrets could enhance the capabilities of charge trapping and storage, which are promising for OFET memory devices.
Abstract In this study, a kind of fluorinated copolyfluorene, named poly[（4-（octyloxy）-9,9-diphenylfluorene-2,7-diyl）-alt- （2,3,5,6-tetrafluoro-1,4-phenylene）] （PODPF-TFP）, is synthesized by facile palladium-based direct aromatization. Compared to the non-fluorinated counterpart, poly[（4-（octyloxy）-9,9-diphenylfluorene-2,7-diyl）-alt-（p-phenylene）] （PODPF-P）, deeper HOMO/LUMO energy level combined with steric hindrance effect endow PODPF-TFP with excellent spectra and morphology stability. Finally, organic field-effect transistor （OFET） memory devices are fabricated with PODPF-P/PODPF- TFP as the dielectric layers, and they both exhibit flash type storage characteristic. Owing to the electronegativity of fluorine atom, the device based on PODPF-TFP exhibits larger memory window and more stable Ion/Ioff ratio during a retention time of 10^4 s as well as a better aging stability. The present study suggests that fluorinated p-n copolyfluorene electrets could enhance the capabilities of charge trapping and storage, which are promising for OFET memory devices.
基金
financially supported by the National Natural Science Funds for Excellent Young Scholar (No.21322402)
the National Natural Science Foundation of China (Nos.21274064, 61475074, 21504041 and 61136003)
University of Jiangsu Province Natural Science Foundation Project (No.14KJB510027)
Natural Science Foundation of Jiangsu Province (No.BM2012010)
Synergetic Innovation Center for Organic Electronics and Information Displays
Natural Science of the Education Committee of Jiangsu Province (No.15KJB430019)
Jiangsu Planned Projects for Postdoctoral Research Funds (No.1501019B)
