title: Photo-reactive charge trapping memory based on lanthanide complex.
abstract: Traditional utilization of photo-induced excitons is popularly but restricted in the fields of photovoltaic devices as well as photodetectors, and efforts on broadening its function have always been attempted. However, rare reports are available on organic field effect transistor (OFET) memory employing photo-induced charges. Here, we demonstrate an OFET memory containing a novel organic lanthanide complex Eu(tta)3ppta (Eu(tta)3 = Europium(III) thenoyltrifluoroacetonate, ppta = 2-phenyl-4,6-bis(pyrazol-1-yl)-1,3,5-triazine), in which the photo-induced charges can be successfully trapped and detrapped. The luminescent complex emits intense red emission upon ultraviolet (UV) light excitation and serves as a trapping element of holes injected from the pentacene semiconductor layer. Memory window can be significantly enlarged by light-assisted programming and erasing procedures, during which the photo-induced excitons in the semiconductor layer are separated by voltage bias. The enhancement of memory window is attributed to the increasing number of photo-induced excitons by the UV light. The charges are stored in this luminescent complex for at least 10(4) s after withdrawing voltage bias. The present study on photo-assisted novel memory may motivate the research on a new type of light tunable charge trapping photo-reactive memory devices.
authors.affiliation: Department of Physics and Materials Science, City University of Hong Kong, Kowloon Tong, Hong Kong SAR.
authors.forename: Jiaqing
authors.initials: J
authors.lastname: Zhuang
authors.affiliation: Department of Applied Biological and Chemical Technology, The Hong Kong Polytechnic University, Hung Hum, Hong Kong SAR.
authors.forename: Wai-Sum
authors.initials: WS
authors.lastname: Lo
authors.affiliation: Department of Physics and Materials Science, City University of Hong Kong, Kowloon Tong, Hong Kong SAR.
authors.forename: Li
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Department of Physics and Materials Science, City University of Hong Kong, Kowloon Tong, Hong Kong SAR.
authors.forename: Qi-Jun
authors.initials: QJ
authors.lastname: Sun
authors.affiliation: Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR.
authors.forename: Chi-Fai
authors.initials: CF
authors.lastname: Chan
authors.affiliation: Department of Physics and Materials Science, City University of Hong Kong, Kowloon Tong, Hong Kong SAR.
authors.forename: Ye
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Department of Physics and Materials Science, City University of Hong Kong, Kowloon Tong, Hong Kong SAR.
authors.forename: Su-Ting
authors.initials: ST
authors.lastname: Han
authors.affiliation: Department of Physics and Materials Science, City University of Hong Kong, Kowloon Tong, Hong Kong SAR.
authors.forename: Yan
authors.initials: Y
authors.lastname: Yan
authors.affiliation: Department of Applied Biological and Chemical Technology, The Hong Kong Polytechnic University, Hung Hum, Hong Kong SAR.
authors.forename: Wing-Tak
authors.initials: WT
authors.lastname: Wong
authors.affiliation: Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR.
authors.forename: Ka-Leung
authors.initials: KL
authors.lastname: Wong
authors.affiliation: Department of Physics and Materials Science, City University of Hong Kong, Kowloon Tong, Hong Kong SAR.
authors.forename: V A L
authors.initials: VA
authors.lastname: Roy