摘要We fabricate an inverted bottom-emission organic light emitting diode (IBOLED) employing two n-doped layers, i.e., 5 nm lithium carbonate doped PTCDA (1:2 Li2CO3:PTCDA) with 5 nm Li2CO3 doped BCP (1:4 Li2CO3:BCP) on top, where PTCDA and BCP stand for 3, 4, 9, 10 perylenetetracarboxylic dianhydride and bathcuporine, respectively. Compared to the IBOED using a layer of 10 nm 1:4 Li2CO3:BCP, the one utilizing the two-layer combination of 5 nm 1:2 Li2CO3:PTCDA and 5 nm 1:4 Li2CO3:BCP shows decreasing operation voltage and thereby increasing power efficiency, mainly attributed to the higher electron conductivity of 1:2 Li2CO3:PTCDA than that of 1:4 Li2CO3:BCP. The mechanism of the electron transport through the interface of 1:2 Li2CO3:PTCDA and 1:4 Li2CO3:BCP is also discussed. We provide a simply and effective structure to enhance the current conduction for IBOLEDs.
Abstract：We fabricate an inverted bottom-emission organic light emitting diode (IBOLED) employing two n-doped layers, i.e., 5 nm lithium carbonate doped PTCDA (1:2 Li2CO3:PTCDA) with 5 nm Li2CO3 doped BCP (1:4 Li2CO3:BCP) on top, where PTCDA and BCP stand for 3, 4, 9, 10 perylenetetracarboxylic dianhydride and bathcuporine, respectively. Compared to the IBOED using a layer of 10 nm 1:4 Li2CO3:BCP, the one utilizing the two-layer combination of 5 nm 1:2 Li2CO3:PTCDA and 5 nm 1:4 Li2CO3:BCP shows decreasing operation voltage and thereby increasing power efficiency, mainly attributed to the higher electron conductivity of 1:2 Li2CO3:PTCDA than that of 1:4 Li2CO3:BCP. The mechanism of the electron transport through the interface of 1:2 Li2CO3:PTCDA and 1:4 Li2CO3:BCP is also discussed. We provide a simply and effective structure to enhance the current conduction for IBOLEDs.
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2010, Vol. 27 
